@inproceedings{SteindlMottokMeieretal., author = {Steindl, Michael and Mottok, J{\"u}rgen and Meier, Hans and Schiller, Frank and Fr{\"u}chtl, M.}, title = {Safeguarded Processing of Sensor Data}, series = {IT-SecurityArea (IT-SA 2009) vom 13.-15. Oktober 2009, N{\"u}rnberg}, booktitle = {IT-SecurityArea (IT-SA 2009) vom 13.-15. Oktober 2009, N{\"u}rnberg}, pages = {8}, abstract = {The spectrum of software tasks no longer includes only rare function controlling tasks for sensor actuator chains in reactive embedded systems. However, more and more responsible challenges like safety-critical scenarios are tackled. Therefore sensor data have to be safeguarded by several mechanism. An obvious and widely used approach is the use of two redundant hardware controllers, but this comes along with an additional cost, space and energy factor. Another way to fulfill certain safety properties is to implement a second diverse software channel in a single micro-controller architecture according the Safely Embedded Software (SES) approach. However, a lack of performance occurs by implementing this diverse channel for complex computations e.g. floating-point operations. This paper gives an approach for transferring the SES into a coprocessor and to migrate SES to a flexible and powerful FPGA architecture.}, language = {en} } @inproceedings{SteindlMottokMeieretal., author = {Steindl, Michael and Mottok, J{\"u}rgen and Meier, Hans and Schiller, Frank and Fr{\"u}chtl, M.}, title = {Safeguarded Processing of Sensor Data}, series = {5th Embedded Real Time Software and Systems Conference (ERTS2 2010), May 2010, Toulouse, France}, booktitle = {5th Embedded Real Time Software and Systems Conference (ERTS2 2010), May 2010, Toulouse, France}, language = {en} } @inproceedings{EdlerHanschPrommesbergeretal., author = {Edler, Simon and Hansch, Walter and Prommesberger, Christian and Schreiner, Rupert}, title = {Influence of adsorbates on the performance of a field emitter array in a high voltage triode setup}, series = {International Vacuum Nanoelectronics Conference (IVNC), 31st, 2018, Kyoto, Japan}, booktitle = {International Vacuum Nanoelectronics Conference (IVNC), 31st, 2018, Kyoto, Japan}, publisher = {IEEE}, doi = {10.1109/IVNC.2018.8520214}, pages = {1-2}, abstract = {The influence of residual gas pressure on the characteristics of black-Silicon field emitter arrays in a high voltage triode setup is investigated. I-Vcharacteristics at different pressure levels show a decrease of emission current with rising pressure. This can be explained by an increase of the work function and charging of the emitter surface due to adsorbates. The initial characteristics can be restored by heating the FEA up to 110 °C during electron emission. This regeneration procedure enables an extension of the lifetime from about 20 h to 440 h at a residual gas pressure of 10 -5 mbar.}, language = {en} } @inproceedings{KaesbauerSchmailzlPrehmetal., author = {K{\"a}sbauer, Johannes and Schmailzl, Anton and Prehm, Jens and Loose, Tobias and Hierl, Stefan}, title = {Simulation of Quasi-Simultaneous Laser Transmission Welding of Plastics}, series = {Procedia CIRP}, volume = {94}, booktitle = {Procedia CIRP}, publisher = {Elsevier}, doi = {10.1016/j.procir.2020.09.136}, pages = {737 -- 741}, abstract = {Thermo-mechanical simulation offers great opportunities to optimize welding processes of plastics. For realistic simulation, the temperature dependent mechanical properties need to be implemented from ambient temperature to temperatures above the flow temperature. Standard test methods are insufficient for characterization in the entire temperature range because close to the flow temperature the material is too soft for tensile tests and too stiff for rheometry. Therefore, an optimization strategy is developed, that determines unknown material parameters by testing in welding simulations. The unknown parameters are iteratively adjusted to minimize the mismatch between computed and measured set-paths. Thus, important process characteristics are calculated realistically, enabling the computer aided assessment of the weld quality.}, subject = {Kunststoffschweißen}, language = {en} } @article{WeiglFeldmeierBierletal., author = {Weigl, Stefan and Feldmeier, Florian and Bierl, Rudolf and Matysik, Frank-Michael}, title = {Photoacoustic detection of acetone in N2 and synthetic air using a high power UV LED}, series = {Sensors Actuators B Chemical}, volume = {316}, journal = {Sensors Actuators B Chemical}, number = {August}, publisher = {Elsevier}, doi = {10.1016/j.snb.2020.128109}, pages = {1 -- 11}, abstract = {The performance of a photoacoustic trace gas sensor for the detection of acetone in N2 and synthetic air is reported. The sensor system utilises an amplitude modulated UV LED. The light source has an emission maximum at 278 nm and a maximum CW output power of 300 mW according to the datasheet. Three different collimating and focusing approaches have been investigated to guide the highly divergent LED light into the acoustic resonator of the photoacoustic measurement cell. A 3D printed aluminium cell was designed to optimize light coupling by simultaneously minimizing the photoacoustic background signal generation. Hence, the diameter of the resonator was set to a comparable large diameter of 10 mm and the inner walls of the resonator were mirror polished. The additive manufacturing procedure allowed for integration of a spirally formed gas channel, enabling gas heating prior to detection. The sensor performance was investigated by measuring acetone in N2 and synthetic air at different concentrations. The UV LED current was set to 86 \% of the maximum value according to the datasheet of the light source in order to increase the lifetime and thermal stability. An Allan-Werle deviation analysis validates a stable sensor performance. The limit of detection (LoD) was determined at a 3σ noise level with a 10 s lock-in amplifier time constant by sampling data points over 20 s with a data acquisition rate of 5 Hz. LoDs of 80.8 ppbV and 19.6 ppbV were obtained for acetone in N2 and synthetic air, respectively.}, language = {en} } @article{BerndtMuggliWittweretal., author = {Berndt, Dominik and Muggli, Josef and Wittwer, Franz and Langer, Christoph and Heinrich, Stephan and Knittel, Thorsten and Schreiner, Rupert}, title = {MEMS-based thermal conductivity sensor for hydrogen gas detection in automotive applications}, series = {Sensors and Actuators A: Physical}, volume = {305}, journal = {Sensors and Actuators A: Physical}, number = {April}, publisher = {Elsevier}, doi = {10.1016/j.sna.2019.111670}, abstract = {Accurate detection of hydrogen gas in vehicle interiors is very important for the future of a fuel cell car. Since this type of gas is highly volatile and flammable, the measurement methods have to be very reliable and precise due to safety reasons. In this paper a thermal conductivity sensor for hydrogen gas detection is presented, exhibiting a lower detection limit of 2000 ppm hydrogen in laboratory air. The sensor element is realized by micro-fabrication techniques on silicon wafers. The heated filament is exposed by a selective wet etching process creating a micro-hotplate on a thin membrane. In order to minimize power consumption, the sensor is operated in pulsed mode. Hydrogen gas detection was carried out using a synthetic gas testbench. Measurements of hydrogen contents ranging from 0\% to 4\% with an increment of 0.5\% were successfully performed for ambient gas temperatures between -15°C and 84°C. Including humidity, high moisture contents have the greatest influence on thermal conductivity. This was predicted in theoretical investigations and confirmed in experiments. For evaluation, both the change in resistance ΔR as well as the time constant τ were taken as sensor output. For both quantities, the previously established theoretical relationship with thermal conductivity could be confirmed.}, language = {en} } @article{WeiglWittmannRuecketal., author = {Weigl, Stefan and Wittmann, Elisabeth and R{\"u}ck, Thomas and Bierl, Rudolf and Matysik, Frank-Michael}, title = {Effects of ambient parameters and cross-sensitivities from O2, CO2 and H2O on the photoacoustic detection of acetone in the UV region}, series = {Sensors Actuators B Chemical}, journal = {Sensors Actuators B Chemical}, number = {328}, publisher = {Elsevier}, issn = {0925-4005}, doi = {10.1016/j.snb.2020.129001}, abstract = {We present a sensitive UV LED photoacoustic setup for the detection of gaseous acetone and discuss its applicability towards breath analysis. We investigated the performance of the sensor for low acetone concentrations down to 0.1 parts per million (ppmV). The influences of temperature, flow, pressure, optical power and LED duty cycle on the measured signal have been examined. To gain a better understanding of the different effects on the photoacoustic signal, correlation analysis was applied and feature importance was determined using a large measured dataset. Furthermore, the cross-sensitivities towards O2, CO2 and H2O have been studied extensively. Finally, the sensor's performance to detect acetone between 0.1-1 ppmV within gas mixtures simulating breath exhale conditions has been investigated, too. With a limit of detection (LoD) of 12.5 parts per billion (ppbV) (3σ) measured under typical breath exhale gas mixture conditions, the sensor demonstrated a high potential for the application of acetone detection in human breath analysis.}, language = {en} } @inproceedings{SchubertSeignDaietal., author = {Schubert, Martin J. W. and Seign, Stefan and Dai, Q. and Hinterseer, Sebastian and Pielmeier, F. and Pietsch, Alexander and Seebauer, C. and Weiß, Josef and Yu, C. and Zenger, Stefan}, title = {Capacitive Sensor Technology for Soil Moisture Monitoring Networks}, series = {24th IEEE International Conference on Electronics, Circuits and Systems (ICECS), 5-8 Dec. 2017, Batumi, Georgia}, booktitle = {24th IEEE International Conference on Electronics, Circuits and Systems (ICECS), 5-8 Dec. 2017, Batumi, Georgia}, doi = {10.1109/ICECS.2017.8292018}, pages = {190 -- 193}, abstract = {A sensor technology for tracking soil-moisture in agricultural fields is presented. A linear measurement method was developed to satisfy the need for cheap sensors with wide range of capacitance change such as factor 30. A combined wired and wireless network transmits data to a server. Various battery aspects are compared with respect to use in agriculture.}, language = {en} } @inproceedings{Schubert, author = {Schubert, Martin J. W.}, title = {System Contemplations for Precision Irrigation in Agriculture}, series = {AIP Conference Proceedings}, volume = {1828}, booktitle = {AIP Conference Proceedings}, number = {1}, isbn = {9780735414969}, doi = {10.1063/1.4979393}, abstract = {This communication contemplates political, biological and technical aspects for efficient and profitable irrigation in sustainable agriculture. A standard for irrigation components is proposed. The need for many, and three-dimensionally distributed, soil measurement points is explained, thus enabling the control of humidity in selected layers of earth. Combined wireless and wired data transmission is proposed. Energy harvesting and storage together with mechanical sensor construction are discussed.}, language = {en} } @inproceedings{LeeSchubertHo, author = {Lee, Wai-Kong and Schubert, Martin J. W. and Ho, Stanley Jian-Qin}, title = {Multi-source energy harvesting and storage for floating wireless-sensor-network nodes}, series = {2016 IEEE Industrial Electronics and Applications Conference (IEACon 2016), 20.-22. Nov. 2016, Kota Kinabalu, Malaysia}, booktitle = {2016 IEEE Industrial Electronics and Applications Conference (IEACon 2016), 20.-22. Nov. 2016, Kota Kinabalu, Malaysia}, isbn = {9781509009268}, language = {en} } @misc{SchubertSeign, author = {Schubert, Martin J. W. and Seign, Stefan}, title = {Arrangement for Measuring Capacitance}, language = {en} } @article{Weber, author = {Weber, Karsten}, title = {Die Macht der Maschinenmoral}, series = {Schweizer Monat}, journal = {Schweizer Monat}, number = {1077 - Juni}, language = {de} } @article{GerhardsWeberBittneretal., author = {Gerhards, Helene and Weber, Karsten and Bittner, Uta and Fangerau, Heiner}, title = {Machine Learning Healthcare Applications (ML-HCAs) Are No Stand-Alone Systems but Part of an Ecosystem - A Broader Ethical and Health Technology Assessment Approach is Needed}, series = {The American Journal of Bioethics - AJOB}, volume = {20}, journal = {The American Journal of Bioethics - AJOB}, number = {11}, doi = {10.1080/15265161.2020.1820104}, pages = {46 -- 48}, language = {de} } @article{StadlerHofmannMotschmannetal., author = {Stadler, Dominik and Hofmann, Matthias J. and Motschmann, Hubert and Shamonin (Chamonine), Mikhail}, title = {Automotived system for measuring the surface dilational modulus of liquid-air interfaces}, series = {Measurement Science and Technology}, volume = {27}, journal = {Measurement Science and Technology}, number = {6}, publisher = {IOP Science}, doi = {10.1088/0957-0233/27/6/065301}, pages = {065301}, abstract = {The surface dilational modulus is a crucial parameter for describing the rheological properties of aqueous surfactant solutions. These properties are important for many technological processes. The present paper describes a fully automated instrument based on the oscillating bubble technique. It works in the frequency range from 1 Hz to 500 Hz, where surfactant exchange dynamics governs the relaxation process. The originality of instrument design is the consistent combination of modern measurement technologies with advanced imaging and signal processing algorithms. Key steps on the way to reliable and precise measurements are the excitation of harmonic oscillation of the bubble, phase sensitive evaluation of the pressure response, adjustment and maintenance of the bubble shape to half sphere geometry for compensation of thermal drifts, contour tracing of the bubbles video images, removal of noise and artefacts within the image for improving the reliability of the measurement, and, in particular, a complex trigger scheme for the measurement of the oscillation amplitude, which may vary with frequency as a result of resonances. The corresponding automation and programming tasks are described in detail. Various programming strategies, such as the use of MATLAB® software and native C++ code are discussed. An advance in the measurement technique is demonstrated by a fully automated measurement. The instrument has the potential to mature into a standard technique in the fields of colloid and interface chemistry and provides a significant extension of the frequency range to established competing techniques and state-of-the-art devices based on the same measurement principle.}, language = {en} } @inproceedings{SilberbauerLindnerSchreiner, author = {Silberbauer, Theodor and Lindner, Matthias and Schreiner, Rupert}, title = {Charakterisierung der dielektrischen Barrierenentladung von Mikroplasmaaktuatoren in Abh{\"a}ngigkeit der Substratdicke}, series = {Intelligente Systeme und ihre Komponenten: Forschung und industrielle Anwendung : Fachbeitr{\"a}ge 2. Symposium Elektronik und Systemintegration ESI 2020}, booktitle = {Intelligente Systeme und ihre Komponenten: Forschung und industrielle Anwendung : Fachbeitr{\"a}ge 2. Symposium Elektronik und Systemintegration ESI 2020}, address = {Landshut}, pages = {64 -- 72}, language = {de} } @article{KrysztofMieraUrbańskietal., author = {Krysztof, Michał and Miera, Paweł and Urbański, Paweł and Grzebyk, Tomasz and Hausladen, Matthias and Schreiner, Rupert}, title = {Integrated silicon electron source for high vacuum microelectromechanical system devices}, series = {Journal of Vacuum Science \& Technology B}, volume = {42}, journal = {Journal of Vacuum Science \& Technology B}, number = {2}, publisher = {AIP Publishing}, issn = {2166-2746}, doi = {10.1116/6.0003385}, abstract = {The article presents the process of developing a silicon electron source designed for high-vacuum microelectromechanical system (HV MEMS) devices, i.e., MEMS electron microscope and MEMS x-ray source. Technological constraints and issues of such an electron source are explained. The transition from emitters made of carbon nanotubes to emitters made of pure silicon is described. Overall, the final electron source consists of a silicon tip emitter and a silicon gate electrode integrated on the same glass substrate. The source generates an electron beam without any carbon nanotube coverage. It generates a high and stable electron current and works after the final bonding process of an HV MEMS device.}, language = {en} } @article{SchreinerNaegeleKoerbletal., author = {Schreiner, Rupert and Naegele, Peter and K{\"o}rbl, M. and Groning, A. and Gentner, Jean-Louis and Schweizer, Heinz C.}, title = {Monolithically integrated tunable laterally coupled distributed-feedback lasers}, series = {Photonics Technology Letters}, volume = {13}, journal = {Photonics Technology Letters}, number = {12}, publisher = {IEEE}, doi = {10.1109/68.969880}, pages = {1277 -- 1279}, abstract = {A new method for fabrication of tunable InGaAsP-InP single-mode lasers without epitaxial overgrowth is reported. These devices show the advantage of a considerably simplified fabrication process compared to conventional tunable laser types. The lasers comprise an active Bragg reflector integrated with an uncorrugated separately pumped gain region. By adjusting the current through the Bragg reflector, the wavelength can be tuned between 1590.8 and 1595.2 nm.}, language = {en} } @unpublished{PangerlSukulRuecketal., author = {Pangerl, Jonas and Sukul, Pritam and R{\"u}ck, Thomas and Fuchs, Patricia and Weigl, Stefan and Miekisch, Wolfram and Bierl, Rudolf and Matysik, Frank-Michael}, title = {An Inexpensive Uv-Led Photoacoustic Based Real-Time Sensor-System Detecting Exhaled Trace-Acetone}, publisher = {Elsevier}, doi = {10.2139/ssrn.4724198}, abstract = {In this research we present a low-cost system for breath acetone analysis based on UV-LED photoacoustic spectroscopy. We considered the end-tidal phase of exhalation, which represents the systemic concentrations of volatile organic compounds (VOCs) - providing clinically relevant information about the human health. This is achieved via the development of a CO2-triggered breath sampling system, which collected alveolar breath over several minutes in sterile and inert containers. A real-time mass spectrometer is coupled to serve as a reference device for calibration measurements and subsequent breath analysis. The new sensor system provided a 3σ detection limit of 6.4 ppbV and an NNEA of 1.1E-9 Wcm-1Hz-0.5. In terms of the performed breath analysis measurements, 12 out of 13 fell within the error margin of the photoacoustic measurement system, demonstrating the reliability of the measurements in the field.}, language = {en} } @inproceedings{BuchnerKaiserHausladenetal., author = {Buchner, Philipp and Kaiser, Alexander and Hausladen, Matthias and Bartl, Mathias and Bachmann, Michael and Schreiner, Rupert}, title = {Silicon Nanowire Field Emitters with Integrated Extraction Gates Using Benzocyclobutene as an Insulator}, series = {37th International Vacuum Nanoelectronics Conference (IVNC), 15-19 July 2024, Brno, Czech Republic}, booktitle = {37th International Vacuum Nanoelectronics Conference (IVNC), 15-19 July 2024, Brno, Czech Republic}, publisher = {IEEE}, doi = {10.1109/IVNC63480.2024.10652314}, pages = {1 -- 2}, abstract = {We are continuously improving the performance of our field emission electron sources. In this work a geometrically optimized design of electron sources with silicon nanowire field emitters on pillars was fabricated. This new design increased the packing density of the emitters by using a hexagonal arrangement of the pillars and a pillar spacing of 40 µm. Benzocyclobutene was used as the insulator material for an integrated (Cr/Ni) extraction gate. A modified fabrication process for the field emitters further improved reproducibility and reliability. An emission current of about 0.4 mA was measured for 30 minutes at an extraction voltage of 250 V and an anode voltage of 500 V. Electron transmission through the gate reached almost 100\%.}, language = {en} } @article{BerndtMuggliHeckeletal., author = {Berndt, Dominik and Muggli, Josef and Heckel, Robert and Rahiman, Mohd Fuad and Lindner, Matthias and Heinrich, Stephan and Pl{\"o}chinger, Heinz and Schreiner, Rupert}, title = {A Robust Miniaturized Gas Sensor for H₂ and CO₂ Detection Based on the 3ω Method}, series = {Sensors}, volume = {22}, journal = {Sensors}, number = {2}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/s22020485}, pages = {1 -- 17}, abstract = {Gas concentration monitoring is essential in industrial or life science areas in order to address safety-relevant or process-related questions. Many of the sensors used in this context are based on the principle of thermal conductivity. The 3ω-method is a very accurate method to determine the thermal properties of materials. It has its origin in the thermal characterization of thin solid films. To date, there have been very few scientific investigations using this method to determine the thermal properties of gases and to apply it to gas measurement technology. In this article, we use two exemplary gases (H2 and CO2) for a systematical investigation of this method in the context of gas analysis. To perform our experiments, we use a robust, reliable sensing element that is already well established in vacuum measurement technology. This helix-shaped thin wire of tungsten exhibits high robustness against chemical and mechanical influences. Our setup features a compact measurement environment, where sensor operation and data acquisition are integrated into a single device. The experimental results show a good agreement with a simplified analytical model and FEM simulations. The sensor exhibits a lower detection limit of 0.62\% in the case of CO2, and only 0.062\% in case the of H2 at an excitation frequency of 1 Hz. This is one of the lowest values reported in literature for thermal conductivity H2 sensors.}, language = {en} } @article{MonkmanSindersbergerPremetal., author = {Monkman, Gareth J. and Sindersberger, Dirk and Prem, Nina and Szecsey, Tamara}, title = {Smart Stiction}, series = {Robotics \& Automation Engineering Journal}, volume = {4}, journal = {Robotics \& Automation Engineering Journal}, number = {4}, publisher = {Juniper Publishers}, doi = {10.19080/RAEJ.2019.04.555641}, abstract = {Soft robotics could loosely be described as the engineering science of expanded dexterity through controllable flexibility. The exploitation of controllable compliance through the judicious choice of soft flexible members, as opposed to a finite number of rigid kinematic joints, can result in greater dexterity without compromising simplicity. One example is the replacement of segmented mechanical legs with simple compliant material eruciform prolegs. To achieve this in robotics, without introducing additional mechanical joints, mobile surfaces with switchable coefficients of friction is essential. This paper explains how, using silicone based smart materials, the rapid alternation between kinematic and static friction (stiction) may be achieved.}, language = {en} } @article{SchreinerKoerblGraebeldingeretal., author = {Schreiner, Rupert and K{\"o}rbl, M. and Gr{\"a}beldinger, H. and Gentner, Jean-Louis and Schweizer, H.}, title = {Laterally gain-coupled 1.57 [micro sign]m DFB lasers with chromium surface grating and self-aligned Ti/Pt/Au ohmic contact}, series = {Electronics Letters}, volume = {36}, journal = {Electronics Letters}, number = {7}, publisher = {The Institution of Engineering and Technology, IET}, issn = {0013-5194}, doi = {10.1049/el:20000500}, pages = {636 -- 637}, abstract = {A simple method for fabricating gain coupled DFB lasers with lateral surface chromium Bragg gratings and self-aligned low capacitance ohmic contacts is reported. These InGaAsP/InP lasers show monomode emission with a sidemode suppression ratio of 40 dB. For 243 µm long devices a continuous wave threshold current of 17 mA was measured at room temperature.}, language = {en} } @article{RueckBierlMatysik, author = {R{\"u}ck, Thomas and Bierl, Rudolf and Matysik, Frank-Michael}, title = {NO2 trace gas monitoring in air using off-beam quartz enhanced photoacoustic spectroscopy (QEPAS) and interference studies towards CO2, H2O and acoustic noise}, series = {Sensors and Actuators B: Chemical}, volume = {255}, journal = {Sensors and Actuators B: Chemical}, number = {Part 3, February}, publisher = {Elsevier}, doi = {10.1016/j.snb.2017.09.039}, pages = {2462 -- 2471}, abstract = {We present the development and characterization as well as comprehensive interference studies of a photoacoustic NO2 trace gas detection system. The system is based on an off-beam quartz enhanced photoacoustic scheme (off-beam QEPAS) and signal generation was initiated by amplitude modulating a low-cost diode laser emitting at 450 nm. The QEPAS sensor element features double-resonant amplification, still it is only ∼ 5 × 5 × 2.5 mm in size. The individual and combined resonance characteristics were investigated and specified to 52 dB amplification, adding up 15 dB acoustic- and 37 dB mechanical-resonance amplification. The linearity of the photoacoustic signal dependency on the analyte concentration was verified from 200 ppbV to 100 ppmV NO2 in synthetic air. The detection limit (3σ) was determined to 1.8 ppbV using a lock-in time constant of 10 s and an averaging time of 20 s. The normalized noise equivalent absorption coefficient was specified to 2.5·10-8 W cm-1 Hz-0.5. The stability of the signal was investigated over time and a slight drift by 1 per mille was observed after 30 min without temperature stabilizing the photoacoustic cell (PAC). Noise analysis was performed by means of Allan deviation and the inverse dependency of response time and precision of the system on the lock-in time constant was outlined. We performed interference analyses towards N2, O2, CO2, H2O and acoustic noise, respectively. Although neither spectral interferences nor losses due to slow NO2 VT-relaxation were observed, O2 was identified to cause a 15\% signal drop due to VVNO2-O2-relaxation. Changing H2O concentrations were found to cause acoustic detuning, which cannot be compensated by adjusting the frequency of modulation, because of the double-resonant feature of the PAC. However, alternative approaches of compensation were discussed. Finally, we carried out heavy traffic noise simulations and determined the QEPAS setup to be 46 times less susceptible towards ambient noise compared to standard microphone-based photoacoustic setups.}, language = {en} } @article{RueckBierlMatysik, author = {R{\"u}ck, Thomas and Bierl, Rudolf and Matysik, Frank-Michael}, title = {Development and characterization of a laboratory setup for photoacoustic NO2 determination based on the excitation of electronic 2B2 and 2B1 states using a low-cost semiconductor laser}, series = {Sensors and Actuators A: Physical}, volume = {258}, journal = {Sensors and Actuators A: Physical}, publisher = {Elsevier}, address = {Amsterdam, Niederlande}, doi = {10.1016/j.sna.2017.03.024}, pages = {193 -- 200}, abstract = {This work gives a detailed characterization of a laboratory setup for photoacoustic NO2 trace gas detection at the ppb level. The signal generation is based on the excitation of electronic 2B2 and 2B1 states using a low-cost semiconductor laser emitting at 450 nm. An acoustic resonator was used for signal amplification and the modulation frequency of the laser was determined to 3395 Hz in order to gain maximum signal amplification. The quality of resonant amplification was determined to 7.9. The gas samples were NO2 calibration gases diluted with pure nitrogen. The signal-to-noise ratio (SNR) dependency on the flow rate Q and the lock-in time constant τLIA was investigated, respectively, and the optimum values were specified to Q = 500 mL/min and τLIA = 2 s. In case of ambient noise, increasing τLIA to 10 s was evaluated as sufficient for SNR preservation. The noise level was measured in the absence of NO2 and it was determined to be composed of 51\% electronic noise and 49\% gas flow noise. With the analyte concentration ranging from 300 ppbV to 100 ppmV, the linear dependency of the photoacoustic amplitude on the NO2 concentration was specified, the sensitivity was determined to 110 μV/ppmV and the maximum measurement error was calculated to ±0.8\%. The detection limit was determined to 2.0 ppbV. Furthermore, the stability of the signal was investigated and a maximum drift of ±1\% was observed within a measuring period of 30 min. The response time τ90 was specified to 58 s. All results considered, this photoacoustic measuring system, which is based on low-cost signal generation and detection units, provides an excellent basis in view of developing a portable device for photoacoustic trace gas detection.}, language = {en} } @article{RueckBierlMatysik, author = {R{\"u}ck, Thomas and Bierl, Rudolf and Matysik, Frank-Michael}, title = {Low-cost photoacoustic NO2 trace gas monitoring at the pptV-level}, series = {Sensors and Actuators A: Physical}, volume = {263}, journal = {Sensors and Actuators A: Physical}, publisher = {Elsevier}, address = {Amsterdam, Niederlande}, doi = {10.1016/j.sna.2017.06.036}, pages = {501 -- 509}, abstract = {We present the development and the characterization of a photoacoustic NO2 trace gas detection system. The system is based on the implementation of low-cost components, i.e. a mass-produced blue diode laser and a standard MEMS microphone which is commonly built into smartphones, for example. An optimized cell design was realized by means of 3D printing. The linearity of the photoacoustic signal dependency on the analyte concentration was verified from 200 ppbV to 100 ppmV NO2. The detection limit (1σ) was determined to 33 pptV and the normalized noise equivalent absorption coefficient was calculated to 7.0 ∙ 10-10 W cm-1 Hz-1/2. The dynamic range of the system was verified to be linear over three magnitudes of order and the sensitivity was calculated to 814 μV/ppmV. The system was characterized in view of optimal operating parameters, i.e. lock-in time constant τLIA and total mass flow rate, optical performance and signal stability. The mass flow dependend response time of the system was specified to 19 s and an idealized step response to a quasi-Heaviside step function was quantified as a function of τLIA. The quality factor of acoustic resonance was determined to 21.9 and an empirical expression regarding acoustic node shifting is provided. The expression takes into account the radius of the resonator pipe and the radius of the hole, which was drilled into the pipe for microphone coupling. Furthermore, we studied the cross-sensitivity of the photoacoustic signal towards H2O and CO2, respectively.}, language = {en} } @misc{WeiglMatysikBierl, author = {Weigl, Stefan and Matysik, Frank-Michael and Bierl, Rudolf}, title = {Development of a sensor system for analysis of human breath exhale}, series = {BayWISS Herbstakademie 2018, Plankstetten}, journal = {BayWISS Herbstakademie 2018, Plankstetten}, abstract = {Atemgasanalyse ist ein junges und vielversprechendes Feld im Bereich der diagnostischen Medizin. Der Ansatz verspricht einfach zug{\"a}ngliche und leicht wiederholbare Probennahme die zum einen non-invasiv ist und zugleich R{\"u}ckschl{\"u}sse auf Vorg{\"a}nge im menschlichen K{\"o}rper und bspw. dessen Gesundheitszustand zul{\"a}sst. Seit Ende des 20. Jahrhunderts gibt es Massenspektrometer die es erm{\"o}glicht haben mehrere Tausend verschiedene Stoffe in der Ausatemluft nachzuweisen. Diese Technologien verbessern sich stetig und erm{\"o}glichen es die Vorg{\"a}nge und Zusammenh{\"a}nge zwischen Zusammensetzung der Ausatemluft und systemischen Prozessen besser zu verstehen. Die bei Studien mit Massenspektrometern ermittelten Biomarker, deren qualitative und quantitative Detektion Gesundheitsdiagnosen erm{\"o}glichen, haben aber noch nicht den Weg in den klinischen Alltag gefunden. Das Problem sind meistens die hohen Anschaffungskosten, komplizierte Datenauswertung und zumeist geringe Verf{\"u}gbarkeit und Immobilit{\"a}t dieser Messger{\"a}te. Die photoakustische Spektroskopie ist eine selektive und hochsensitive Messmethode, die es erm{\"o}glichen soll den Biomarker „Aceton", der grunds{\"a}tzlich die Metabolisierung von Fetten widerspiegelt, schnell und reproduzierbar quantitativ zu detektieren. Dabei m{\"u}ssen Hindernisse wie Querempfindlichkeiten, ausgel{\"o}st durch die komplexe Zusammensetzung der Messmatrix Atemgas, bei gleichzeitig kleine Aceton Konzentrationen (200-800 parts-per-billion) {\"u}berwunden werden. Verschiedene Wellenl{\"a}ngenbereiche mit unterschiedlichen Lichtquellen, akustisch resonante sowie innovative Messzellendesigns und anspruchsvolle Datenauswertung mittels komplexer Algorithmik sind n{\"o}tig um das Ziel, die Entwicklung eines kompakten, g{\"u}nstigen und zuverl{\"a}ssigen Acetonsensors, zu erreichen.}, language = {en} } @inproceedings{RothHauslerBierl, author = {Roth, Carina and Hausler, Peter and Bierl, Rudolf}, title = {Einbindung eines 2D-Photodetektors in einen hochintegrierten SPR-Imaging-Sensor}, series = {118. Jahrestagung der deutschen Gesellschaft f{\"u}r angewandte Optik (DGaO), 6.-10. Juni 2017, Dresden}, booktitle = {118. Jahrestagung der deutschen Gesellschaft f{\"u}r angewandte Optik (DGaO), 6.-10. Juni 2017, Dresden}, abstract = {Mit der Oberfl{\"a}chenplasmonenresonanzspektroskopie (SPR) k{\"o}nnen Brechungsindex{\"a}nderungen eines Analyten von bis zu 10-6 RIU detektiert werden. Das SPR-Imaging bietet heute gegen{\"u}ber der konventionellen SPR-Analyse die M{\"o}glichkeit, mehrere einzelne Messungen parallel durchf{\"u}hren zu k{\"o}nnen. Mit Hilfe eines zweidimensionalen Sensorchips und einer leistungsf{\"a}higen Boardlevelkamera k{\"o}nnen die Abbildungen des Chips direkt an einen Rechner {\"u}bertragen und dort verarbeitet werden. Aufgrund unterschiedlicher Winkelstellungen und der Geometrie des Aufbaus entstehen Stauchungen und Streckungen des abgebildeten Sensorchips, die mit verschiedenen Ans{\"a}tzen aus der Bildverarbeitung ausgeglichen werden, um die Bilder miteinander vergleichen zu k{\"o}nnen. Zudem wird die G{\"u}te der Referenz- und Messbereiche des Chips bestimmt. Diese Algorithmen sind nur m{\"o}glich aufgrund der heutigen, leistungsf{\"a}higen Rechner und der immer gr{\"o}ßer werdenden Durchsatzraten der Kameras. Dabei kommt in dieser Anwendung der relativ neue Kamerastandard USB3 Vision zum Einsatz. Dieser zeichnet sich zus{\"a}tzlich durch das Plug and Play und seinen Standardstecker, der an (fast) jedem Rechner vorhanden ist, aus.}, language = {de} } @inproceedings{ZhouLandgrafRuecketal., author = {Zhou, Qi and Landgraf, Ferdinand and R{\"u}ck, Thomas and Bierl, Rudolf}, title = {Resonance frequency tuning and process design of a micromechanical capacitive cantilever in a photoacoustic trace-gas sensing device}, series = {7. MikroSystemTechnik Kongress "MEMS, Mikroelektronik, Systeme", 23.-25. Oktober 2017, M{\"u}nchen}, booktitle = {7. MikroSystemTechnik Kongress "MEMS, Mikroelektronik, Systeme", 23.-25. Oktober 2017, M{\"u}nchen}, publisher = {VDE-Verlag}, address = {Berlin}, isbn = {978-3-8007-4491-6}, abstract = {Photoacoustic spectroscopy is an efficient method to detect the concentration of trace gases with following advantages: short response time, high sensitivity, continuous and real-time monitoring and the option of miniaturization without the need of complex mirror-based multi-pass cell designs. A micromechanical cantilever is used as a key component in a two-part "Cantilever-Resonator" system that detects the weak photoacoustic signal. The resonance frequency of cantilever needs to be tuned to match the resonance frequency of resonator in order to achieve the maximum vibration amplitude of the "Cantilever-Resonator" system. This paper reports a post-fabrication method to tune the resonance frequency of cantilevers via focused ion beam (FIB) and a capacitive solution for the cantilever to transform the acoustic signal to electrical signal.}, language = {en} } @article{vanderWeerdBierlMatysik, author = {van der Weerd, Bastiaan and Bierl, Rudolf and Matysik, Frank-Michael}, title = {Trends in Electrochemical Sensing of Blood Gases}, series = {Bioanalytical Reviews}, volume = {6}, journal = {Bioanalytical Reviews}, publisher = {Springer}, address = {Berlin}, doi = {10.1007/11663_2016_1}, pages = {263 -- 280}, abstract = {The monitoring of partial pressures of the blood gases carbon dioxide (pCO2) and oxygen (pO2) is of great importance in clinical diagnostics. The measure of pCO2 and pO2 provides essential information about the patient's metabolism, gas exchange, ventilation, and acid-base homeostasis. The conventional electrochemical methods for clinical blood gas analysis are based on the potentiometric Severinghaus sensor for carbon dioxide and the amperometric Clark sensor for oxygen. These techniques are well established and are only shortly discussed in this overview. However, in recent years a variety of modifications of these classical sensor concepts and new approaches of electrochemical sensing of pCO2 and pO2 have been introduced. This review summarizes recent developments in this field and discusses the potential for future applications in clinical blood gas analysis.}, language = {en} } @inproceedings{RueckLaeppleBierl, author = {R{\"u}ck, Thomas and L{\"a}pple, I. and Bierl, Rudolf}, title = {Photoakustische Spurengasanalytik von NO2 im ppt-Bereich (10^-12) bei Verwendung kosteng{\"u}nstiger Einzelkomponenten}, series = {7. MikroSystemTechnik Kongress "MEMS, Mikroelektronik, Systeme", 23.-25. Oktober 2017, M{\"u}nchen}, booktitle = {7. MikroSystemTechnik Kongress "MEMS, Mikroelektronik, Systeme", 23.-25. Oktober 2017, M{\"u}nchen}, publisher = {VDE-Verlag}, address = {Berlin}, isbn = {978-3-8007-4491-6}, language = {de} } @article{ZaglerLandgrafRuecketal., author = {Zagler, Andreas and Landgraf, Ferdinand and R{\"u}ck, Thomas and Bierl, Rudolf}, title = {Entwicklung eines mikromechanischen kapazitiven Schalldetektors im resonanten Betrieb f{\"u}r die photoakustische Spurengasanalyse}, series = {7. MikroSystemTechnik Kongress "MEMS, Mikroelektronik, Systeme", 23.-25. Oktober 2017, M{\"u}nchen}, journal = {7. MikroSystemTechnik Kongress "MEMS, Mikroelektronik, Systeme", 23.-25. Oktober 2017, M{\"u}nchen}, publisher = {VDE-Verlag}, address = {Berlin}, language = {de} } @inproceedings{GaidaWeiglRuecketal., author = {Gaida, Peter and Weigl, Stefan and R{\"u}ck, Thomas and Bierl, Rudolf}, title = {Portable photoakustische Messeinheit zur NO2 Detektion im Spurenbereich}, series = {7. MikroSystemTechnik Kongress "MEMS, Mikroelektronik, Systeme", 23.-25. Oktober 2017, M{\"u}nchen}, booktitle = {7. MikroSystemTechnik Kongress "MEMS, Mikroelektronik, Systeme", 23.-25. Oktober 2017, M{\"u}nchen}, publisher = {VDE-Verlag}, address = {Berlin}, isbn = {978-3-8007-4491-6}, language = {de} } @inproceedings{Fischer, author = {Fischer, Johannes}, title = {Miniaturisierter plasmonischer Sensor f{\"u}r das Monitoring von Weichmachern in Gew{\"a}sserproben}, series = {7. MikroSystemTechnik Kongress "MEMS, Mikroelektronik, Systeme", 23.-25. Oktober 2017, M{\"u}nchen}, booktitle = {7. MikroSystemTechnik Kongress "MEMS, Mikroelektronik, Systeme", 23.-25. Oktober 2017, M{\"u}nchen}, publisher = {VDE-Verlag}, address = {Berlin}, isbn = {978-3-8007-4491-6}, language = {de} } @misc{HauslerRothVitzthumeckeretal., author = {Hausler, Peter and Roth, Carina and Vitzthumecker, Thomas and Fischer, Johannes and Bierl, Rudolf}, title = {Motionless SPR-angle scan with a miniaturized device}, series = {Europtrode XIV, Naples, 25-28 March 2018}, journal = {Europtrode XIV, Naples, 25-28 March 2018}, language = {en} } @inproceedings{WeiglGaidaRuecketal., author = {Weigl, Stefan and Gaida, Peter and R{\"u}ck, Thomas and Bierl, Rudolf}, title = {Portable Measurement Unit for NO2 Trace Gas Detection}, series = {PHOTOPTICS 2018, 6th International Conference on Photonics, Optics and Laser Technology, 25 - 27 January 2018, Funchal Madeira}, booktitle = {PHOTOPTICS 2018, 6th International Conference on Photonics, Optics and Laser Technology, 25 - 27 January 2018, Funchal Madeira}, language = {en} } @techreport{UngerRueckLandgrafetal., author = {Unger, J. and R{\"u}ck, Thomas and Landgraf, Ferdinand and Bierl, Rudolf}, title = {Herstellung und Analyse der Resonanzfrequenz eines MEMS Cantilever f{\"u}r das CEPAS Verfahren}, abstract = {Diese Abhandlung beschreibt das Konzept eines mikroeletromechanischen Systems (MEMS), das im Messverfahren der cantilever enhanced photoacoustic spectroscopy (CEPAS) Verwendung finden soll. Es wird die Herstellung eines einseitig eingespannten Biegebalkens aus Silizium mittels deep reactiv ion etching (DRIE) beschrieben. Des Weiteren wird die Resonanzfrequenz dieses Cantilevers mit Hilfe Laservibrometertechnik untersucht. Die resultierenden resonanten Schwingungen 0.Ordnung werden mit den Ergebnissen einer vereinfachten theoretischen N{\"a}herung verglichen. Die Messergebnisse stehen in gutem Zusammenhang mit den theoretischen Werten. Solche Cantilever, die aus silicon on insula tor (SOI) Wafer angefertigt wurden, weisen bei einer Zielfrequenz ein mittlere Abweichung von Δf = 118±26Hz (bzw.Δf =0,76±0,17\%) auf.}, language = {de} } @inproceedings{HollerHauslerRothetal., author = {Holler, Sven and Hausler, Peter and Roth, Carina and Bierl, Rudolf}, title = {Gestapelte Au-Al-Au und Au-Ag-Au Schichten als aktive Schichten f{\"u}r die Oberfl{\"a}chenplasmonenresonanzspektroskopie}, series = {5. Landshuter Symposium Mikrosystemtechnik, M{\"a}rz 2016}, booktitle = {5. Landshuter Symposium Mikrosystemtechnik, M{\"a}rz 2016}, publisher = {Fachhochschule Landshut}, address = {Landshut}, isbn = {978-3-9812696-9-7}, pages = {192 -- 198}, language = {de} } @inproceedings{RothHauslerBierl, author = {Roth, Carina and Hausler, Peter and Bierl, Rudolf}, title = {Einbindung eines CMOS-Detektors in einen hochintegrierten SPR-Sensor}, series = {5. Landshuter Symposium Mikrosystemtechnik, M{\"a}rz 2016}, booktitle = {5. Landshuter Symposium Mikrosystemtechnik, M{\"a}rz 2016}, publisher = {Fachhochschule Landshut}, address = {Landshut}, isbn = {78-3-9812696-9-7}, pages = {200 -- 205}, language = {de} } @inproceedings{JobstBierl, author = {Jobst, Simon and Bierl, Rudolf}, title = {A Comparison of Correlation and Zero-Crossing Based Techniques in Ultrasonic Measurement}, series = {10th International Symposium on Applied Reconfigurable Computing (ARC'2014), Vilamoura, Algarve, Portugal, 14 - 16 April, 2014}, booktitle = {10th International Symposium on Applied Reconfigurable Computing (ARC'2014), Vilamoura, Algarve, Portugal, 14 - 16 April, 2014}, abstract = {Ultrasound measurement technology has advancedin previous decades due to positive developments in computing power and lower cost for the necessary hardware. Correlation-based processing can be advantageous for high-accuracy measurements, especially in noisy environments. Higher computational load makes correlation less attractive for industrialapplications, though, favouring traditional processing techniques. A platform for comparing various processing techniques hasbeen developed. It was found that both zero-crossing detectionas well as correlation can achieve very high accuracy over a hightemperature range but that correlation-based processing can lead to a significant precision bias depending on system bandwidth.}, language = {en} } @inproceedings{RueckLandgrafLaeppleetal., author = {R{\"u}ck, Thomas and Landgraf, Ferdinand and L{\"a}pple, I. and Unger, J. and Matysik, Frank-Michael and Bierl, Rudolf}, title = {Specification of an improved photoacoustic setup for high-sensitive, low-cost NO2 trace gas detection}, series = {18th International Conference on Photoacoustic and Photothermal Phenomena (ICPPP18), 2015, September 6-10, Novi Sad, Serbia}, booktitle = {18th International Conference on Photoacoustic and Photothermal Phenomena (ICPPP18), 2015, September 6-10, Novi Sad, Serbia}, language = {en} } @inproceedings{vanderWeerdBierlMatysik, author = {van der Weerd, Bastiaan and Bierl, Rudolf and Matysik, Frank-Michael}, title = {A Conductivity Probe for the Determination of Carbon Dioxide Tension at the Oxygenator Exhaust Outlet during Extracorporeal Membrane Oxygenation (ECMO)}, series = {analytica Conference 2014, 1. bis 4. April, M{\"u}nchen}, booktitle = {analytica Conference 2014, 1. bis 4. April, M{\"u}nchen}, language = {en} } @inproceedings{vanderWeerdBierlMatysik, author = {van der Weerd, Bastiaan and Bierl, Rudolf and Matysik, Frank-Michael}, title = {A Conductivity Probe for the Determination of Carbon Dioxide Tension at the Oxygenator Exhaust Outlet during Extracorporeal Membrane Oxygenation (ECMO)}, series = {Electrochemistry 2014, September 22 - 24, Mainz}, booktitle = {Electrochemistry 2014, September 22 - 24, Mainz}, language = {en} } @inproceedings{vanderWeerdBierlMatysik, author = {van der Weerd, Bastiaan and Bierl, Rudolf and Matysik, Frank-Michael}, title = {A Planar Conductivity Probe for CO2 Determination at the Oxygenator Outlet}, series = {Doktorandenseminar GDCh Prozessanalytik 2014, Berlin}, booktitle = {Doktorandenseminar GDCh Prozessanalytik 2014, Berlin}, language = {en} } @article{KurzweilSchottenbauerSchell, author = {Kurzweil, Peter and Schottenbauer, Josef and Schell, Christian}, title = {Past, Present and Future of Electrochemical Capacitors: Pseudocapacitance, Aging Mechanisms and Service Life Estimation}, series = {Journal of Energy Storage}, volume = {35}, journal = {Journal of Energy Storage}, number = {March}, publisher = {Elsevier}, doi = {10.1016/j.est.2021.102311}, abstract = {The capacitance values printed on capacitor housings do not reflect the actual capacitance available for any technical application. The complex properties of the pseudocapacitance and the aging behavior of practical supercapacitors are reviewed with regard to the state-of-the-art and the latest findings. The long-term stability of various electrolyte systems and carbon materials is critically examined under phenomenological aspects that reflect the typical fault pattern of supercapacitors. Electrolyte resistance and voltammetric capacitance are reliable aging indicators. High temperatures have a greater impact on service life than high voltages, and overvoltages are worse than high currents. The anode more than the cathode suffers from a loss of pore volume, increase of nitrogen and fluorine compounds, and the unstable adhesive layer between active carbon and aluminum. Unwanted material changes and chemical reactions in the supercapacitor reflect the influence of water over several years in the life test. Credible reaction pathways are identified for the known aging processes. Fundamentals and materials are reviewed in a separate part.**}, language = {en} } @article{SteiningerGadererDawoudetal., author = {Steininger, Peter and Gaderer, Matthias and Dawoud, Belal and Gaderer, Matthias}, title = {Experimental and numerical study on the solar gain and heat loss of typical existing and refurbished German buildings}, series = {iCRBE Procedia}, volume = {1}, journal = {iCRBE Procedia}, number = {1}, publisher = {Weentech}, doi = {10.32438/icrbe.202035}, pages = {75 -- 93}, abstract = {This communication introduces an experimental setup for investigating the effect of solar radiation on the reduction of transmission heat losses and the steady state thermal conductance of uninsulated and insulated multi-layer wall samples. The setup consists of two adjacent climatic chambers, which share a common wall, in which the multi-layer wall samples are mounted. A solar simulator is applied within the outdoor air climatic chamber, whose radiation spectrum and radiation intensity are approximately equivalent to those of the sun. The first tests have been carried out on a wall sample with a typical structure of existing buildings from the year 1930 in Germany. In addition, a high-performance insulating plaster layer has been applied on a basic test sample (with existing building structure) to replicate and assess the refurbished scenario. Furthermore, a numerical investigation on the transient heat transfer process is carried out by using the simulation software COMSOL Multiphysics®. The experimental results of both uninsulated and insulated wall samples are validated against 1D and 3D models. As seen, the uninsulated wall, whose thermal conductance was experimentally determined to be equal to 1.79 W/(m²K), absorbs a heat flux of 208 W/m² through its external wall surface over a period of 8 hours. A fraction of 9.8 \% of the absorbed heat arrives as a gain on the internal wall and reduces the transmission heat losses by 11.7 \% over a period of 55 hours. On the other hand, the thermal conductivity of the insulation layer of the refurbished wall sample with micro hollow glass spheres was estimated by a parameter estimation procedure using the 3D model and the obtained experimental data. Using the estimated thermal conductivity, a thermal conductance of 0.42 W/(m²K) has been obtained for the refurbished wall sample.}, language = {en} } @inproceedings{SindersbergerPremMonkmanetal.2021, author = {Sindersberger, Dirk and Prem, Nina and Monkman, Gareth J. and Zimmermann, Klaus}, title = {Self-Sensing Electroadhesive Polymer Gripper with Magnetically Controllable Surface Geometry}, series = {Actuator 2021, International Conference and Exhibition on New Actuator Systems and Applications: GMM conference, February 17-19, 2021, online event}, booktitle = {Actuator 2021, International Conference and Exhibition on New Actuator Systems and Applications: GMM conference, February 17-19, 2021, online event}, editor = {Schlaak, Helmut}, publisher = {VDE VERLAG}, address = {Berlin; Offenbach}, isbn = {9783800754540}, doi = {10.1002/macp.201800222}, pages = {318 -- 320}, year = {2021}, abstract = {Compared to conventional end effectors, electro-adhesive grippers enable the handling of sensitive, soft or air-permeable materials [1]. The prehension force is based on a strong electric field generated by electrodes resulting in a polarisation of the dielectric and the generation of mirror charges in the workpiece. When the electrode supply voltage is deactivated, the electric field drops,but an electrostatic field remains due to remanent polarisation of the dielectric. The residual charge on the gripper surface reduces only slowly and in combination with other influencing factors can prevent the workpieces from being ejected temporarily or completely. In this work a solution to this problem is presented by means of gripper surface deforming caused by the applicat ion of a magnetic field to a magneto- active polymer (MAP) actuator. The in-creased distance between the workpiece and the dielectric enables precise and controlled ejection. In addition to compliance and deformability, the employment of soft smart materials enables the integration of self-sens-ing mechanisms for the measurement of surface deformation. The embedding of electrically conductive flexible electrodes within the soft silicone dielectric sup port such movements and serves as the n ecessary electrodes for electroadhesion. Since the implementation of the end effectoris based entirely on soft materials, the self-sensing magnetically controllable electroadhesive gripper (SMEG) can be produced in a shape deposition manufacturing (SDM) process [2], [3] and is highly applicable to the field of soft robotics.}, language = {de} } @article{YeapMeisterOhetal., author = {Yeap, Kim Ho and Meister, Tobias and Oh, Zi Xin and Nisar, Humaira}, title = {Circuit Modelling Methodology for Dual-band Planar Antennas}, series = {APPLIED COMPUTATIONAL ELECTROMAGNETICS SOCIETY JOURNAL}, volume = {36}, journal = {APPLIED COMPUTATIONAL ELECTROMAGNETICS SOCIETY JOURNAL}, number = {8}, publisher = {APPLIED COMPUTATIONAL ELECTROMAGNETICS SOC}, doi = {10.47037/2021.ACES.J.360822}, pages = {1112 -- 1115}, abstract = {This paper presents a simple and systematic approach to determine the equivalent frequency-independent circuit model for a dual-band planar antenna. The Foster Canonical network synthesis technique with two RLC tanks has been employed to generate the two resonant bands of the antenna. The transfer function model is subsequently refined using a data fitting algorithm (viz the Nelder-Mead simplex algorithm). Parametric adjustments are performed at the final stage in order to further improve the accuracy of the final parameters.}, language = {en} } @inproceedings{SchorrBoehmZentneretal., author = {Schorr, Philipp and B{\"o}hm, Valter and Zentner, Lena and Zimmermann, Klaus}, title = {Design of a Vibration Driven Motion System Based on a Multistable Tensegrity Structure}, series = {ICINCO 2018: proceedings of the 15th International Conference on Informatics in Control, Automation and Robotics, Porto, Portugal, July 29-31, 2018}, volume = {613}, booktitle = {ICINCO 2018: proceedings of the 15th International Conference on Informatics in Control, Automation and Robotics, Porto, Portugal, July 29-31, 2018}, editor = {Gusikhin, Oleg and Madani, Kurosh}, publisher = {Springer}, address = {Cham}, isbn = {978-3-030-31992-2}, doi = {10.1007/978-3-030-31993-9_14}, pages = {302 -- 317}, abstract = {In this paper a novel approach to realize a uniaxial bidirectional vibration driven motion system with controllable direction of motion is investigated. The considered motion system bases on a tensegrity structure with multiple stable equilibrium configurations. The structure is in contact with a horizontal plane due to gravity and the actuation is realized by the harmonic change of the length of a selected member. Beside varying the actuation parameters, the direction of motion can be controlled by changing the equilibrium configuration of the tensegrity structure. In this paper the topology of the tensegrity structure and the parameter values are chosen appropriately to provide two symmetric equilibrium configurations. A change of the equilibrium state yields a novel configuration of the entire motion system which is symmetric to the original state. Utilizing the symmetry of the system the same actuation yields an opposite motion. This approach represents a reliable opportunity to control the direction of motion by changing the equilibrium state for constant actuation parameters. This paper focuses on the parameter selection and the design of the actuation of the vibration driven motion system. The working principle of the vibration driven motion system is verified by numerical simulations. This contribution represents the theoretical investigation for the further development of a prototype.}, language = {en} } @inproceedings{ThomeczekAttenbergerKolbetal., author = {Thomeczek, Ludwig and Attenberger, Andreas and Kolb, Johannes and Matoušek, Vaclav and Mottok, J{\"u}rgen}, title = {Measuring Safety Critical Latency Sources using Linux Kernel eBPF Tracing}, series = {ARCS 2019: 32nd International Conference on Architecture of Computing Systems : workshop proceedings, May 20- 21, 2019, Technical University of Denmark, Copenhagen, Denmark}, booktitle = {ARCS 2019: 32nd International Conference on Architecture of Computing Systems : workshop proceedings, May 20- 21, 2019, Technical University of Denmark, Copenhagen, Denmark}, editor = {Trinitis, Carsten and Pionteck, Thilo}, publisher = {VDE VERLAG GMBH}, address = {Berlin}, isbn = {978-3-8007-4957-7}, pages = {8}, language = {en} } @article{BaumerShamoninChamonine, author = {Baumer, Johannes and Shamonin (Chamonine), Mikhail}, title = {Abstandsensorsystem basierend auf dem Prinzip der optischen Reflektion f{\"u}r Anwendungen im Bereich Weiße Ware: Intensit{\"a}tsreferenzierung und Linearisierung des Ausgnagssignals}, series = {TM - Technisches Messen}, volume = {81}, journal = {TM - Technisches Messen}, number = {2}, publisher = {de Gruyter}, doi = {10.1515/teme-2014-1014}, pages = {62 -- 69}, abstract = {Ein auf optischer Reflektion basierendes Abstandssensorsystem f{\"u}r die „Weiße Ware" wird hier vorgestellt. Die technische L{\"o}sung greift auf ein allseits bekanntes Intensit{\"a}tsreferenzierungsprinzip - die optische Br{\"u}cke - zur{\"u}ck. Der Einfluss der Umgebungstemperatur kann kompensiert werden. St{\"o}reffekte wie alterungsbedingte Drift der optischen Elemente oder Systemvariationen der Empfindlichkeit verursacht durch die Streuung der einzelnen Komponenten k{\"o}nnen erfolgreich gehandhabt werden. Ein Algorithmus zur Ausgangslinearisierung und dessen Optimierung in Hinblick auf einen kosteng{\"u}nstigen Mikrokontroller wird beschrieben. Zum Schluss wird ein Prototyp eines Fertigungsautomaten, der zur Herstellung dieses Sensors dient, und dessen grundlegende Funktion vorgestellt. A reflective optical sensor system for distance measurements in white-goods applications is presented. The technical solution implements a well-known intensity referencing principle - the optical bridge - in a low-cost design. The influence of the ambient temperature can be compensated for. The spurious effects such as slow output drift caused by aging of optical components or the variation of the system sensitivity due to the parameter spreading of system components can be successfully overcome as well. An algorithm for linearizing the system response is described and optimized for a low-cost microcontroller. Finally, a prototype of an assembly line, which is used for producing this sensor system, is described and its basic funcionallity is demonstrated.}, language = {de} } @article{FuersattelPlankMaieretal., author = {Fuersattel, Peter and Plank, Claus and Maier, Andreas and Riess, Christian}, title = {Accurate laser scanner to camera calibration with application to range sensor evaluation}, series = {IPSJ Transactions on Computer Vision and Applications}, volume = {9}, journal = {IPSJ Transactions on Computer Vision and Applications}, number = {1}, publisher = {Springer Nature}, doi = {10.1186/s41074-017-0032-5}, abstract = {Multi-modal sensory data plays an important role in many computer vision and robotics tasks. One popular multi-modal pair is cameras and laser scanners. To overlay and jointly use the data from both modalities, it is necessary to calibrate the sensors, i.e., to obtain the spatial relation between the sensors. Computing such a calibration is challenging as both sensors provide quite different data: cameras yield color or brightness information, laser scanners yield 3-D points. However, several laser scanners additionally provide reflectances, which turn out to make calibration to a camera well feasible. To this end, we first estimate a rough alignment of the coordinate systems of both modalities. Then, we use the laser scanner reflectances to compute a virtual image of the scene. Stereo calibration on the virtual image and the camera image are then used to compute a refined, high-accuracy calibration. It is encouraging that the accuracies in our experiments are comparable to camera-camera stereo setups and outperform another of other target-based calibration approach. This shows that the proposed algorithm reliably integrates the point cloud with the intensity image. As an example application, we use the calibration results to obtain ground-truth distance images for range cameras. Furthermore, we utilize this data to investigate the accuracy of the Microsoft Kinect V2 time-of-flight and the Intel RealSense R200 structured light camera.}, language = {en} } @article{SchreinerLangerPrommesbergeretal., author = {Schreiner, Rupert and Langer, Christoph and Prommesberger, Christian and Dams, Florian}, title = {Compact and Energy-Efficient Field Emission Cathodes for Sensor Applications}, series = {Advanced Materials Research}, volume = {1024}, journal = {Advanced Materials Research}, publisher = {Scientific.net}, doi = {10.4028/www.scientific.net/amr.1024.372}, pages = {372 -- 375}, abstract = {We report on miniaturized silicon field emitter arrays for the application in compact and energy-saving vacuum-microelectronic devices, e.g. sensors or x-ray tubes. Since standard silicon semiconductor technology has been used for the fabrication, they may be easily integrated with other silicon based circuits and devices on the same chip. The silicon tip geometry and the operating conditions were optimized in order to obtain highly uniform and stable electron field emission from large area cathode arrays. A series of uniform hexagonal tip arrays containing each 547 tips were fabricated and characterized. The electron emission properties of both individual tips as well as of complete emitter arrays were investigated. A saturation level in the voltage-current characteristics was found, which can be explained by the limitation of the supply of electrons due to the p-type silicon wafer material. When operating the arrays in the current saturation regime at an emission current of ~ 1 nA per tip, a highly stable and low noise emission can be observed.}, language = {en} } @article{BurdinChashinEkonomovetal., author = {Burdin, Dmitrii A. and Chashin, Dmitri V. and Ekonomov, Nikolai A. and Fetisov, Leonid Y. and Fetisov, Yuri K. and Shamonin (Chamonine), Mikhail}, title = {DC magnetic field sensing based on the nonlinear magnetoelectric effect in magnetic heterostructures}, series = {Journal of physics D: Applied physics}, volume = {49}, journal = {Journal of physics D: Applied physics}, number = {37}, publisher = {IOP Publishing}, doi = {10.1088/0022-3727/49/37/375002}, abstract = {Recently, highly sensitive magnetic field sensors using the magnetoelectric effect in composite ferromagnetic-piezoelectric layered structures have been demonstrated. However, most of the proposed concepts are not useful for measuring dc magnetic fields, because the conductivity of piezoelectric layers results in a strong decline of the sensor's sensitivity at low frequencies. In this paper, a novel functional principle of magnetoelectric sensors for dc magnetic field measurements is described. The sensor employs the nonlinear effect of voltage harmonic generation in a composite magnetoelectric structure under the simultaneous influence of a strong imposed ac magnetic field and a weak dc magnetic field to be measured. This physical effect arises due to the nonlinear dependence of the magnetostriction in the ferromagnetic layer on the magnetic field. A sensor prototype comprising of a piezoelectric fibre transducer sandwiched between two layers of the amorphous ferromagnetic Metglas (R) alloy was fabricated. The specifications regarding the magnetic field range, frequency characteristics, and noise level were studied experimentally. The prototype showed the responsivity of 2.5 V mT(-1) and permitted the measurement of dc magnetic fields in the range of similar to 10 nT to about 0.4 mT. Although sensor operation is based on the nonlinear effect, the sensor response can be made linear with respect to the measured magnetic field in a broad dynamic range extending over 5 orders of magnitude. The underlying physics is explained through a simplified theory for the proposed sensor. The functionality, differences and advantages of the magnetoelectric sensor compare well with fluxgate magnetometers. The ways to enhance the sensor performance are considered.}, language = {en} } @article{DiermeierSindersbergerAngeleetal., author = {Diermeier, Andreas and Sindersberger, Dirk and Angele, Peter and Kujat, Richard and Monkman, Gareth J.}, title = {Sensor system for use with low intensity pulsed ultrasound}, series = {Sensor review}, volume = {39}, journal = {Sensor review}, number = {6}, publisher = {Emerald}, issn = {0260-2288}, doi = {10.1108/SR-11-2018-0304}, pages = {828 -- 834}, abstract = {Purpose Ultrasound is a well-established technology in medical science, though many of the conventional measurement systems (hydrophones and radiation force balances [RFBs]) often lack accuracy and tend to be expensive. This is a significant problem where sensors must be considered to be "disposable" because they inevitably come into contact with biological fluids and expense increases dramatically in cases where a large number of sensors in array form are required. This is inevitably the case where ultrasound is to be used for the in vitro growth stimulation of a large plurality of biological samples in tissue engineering. Traditionally only a single excitation frequency is used (typically 1.5 MHz), but future research demands a larger choice of wavelengths for which a single broadband measurement transducer is desirable. Furthermore, because of implementation conditions there can also be large discrepancies between measurements. The purpose of this paper deals with a very cost-effective alternative to expensive RFBs and hydrophones. Design/methodology/approach Utilization of cost-effective piezoelectric elements as broadband sensors. Findings Very effective results with equivalent (if not better) accuracy than expensive alternatives. Originality/value This paper concentrates on how very cost-effective piezoelectric ultrasound transducers can be implemented as sensors for ultrasound power measurements with accuracy as good, if not better than those achievable using radiation force balances or hydrophones.}, language = {en} } @inproceedings{HausladenBomkeBuchneretal., author = {Hausladen, Matthias and Bomke, Vitali and Buchner, Philipp and Bachmann, Michael and Knapek, Alexandr and Schreiner, Rupert}, title = {Influence of Geometrical Arrangements of Si Tip Arrays Fabricated by Laser Micromachining on their Emission Behaviour}, series = {2021 34th International Vacuum Nanoelectronics Conference (IVNC): 7/5/2021 - 7/9/2021, Lyon, France}, booktitle = {2021 34th International Vacuum Nanoelectronics Conference (IVNC): 7/5/2021 - 7/9/2021, Lyon, France}, publisher = {IEEE}, address = {Piscataway, N.J.}, isbn = {978-1-6654-2589-6}, issn = {2380-6311}, doi = {10.1109/IVNC52431.2021.9600717}, abstract = {ensely packed emitters on a field emission array lead typically to mutual shielding. Taking biology as a role model for geometric arrangements could be a way to reduce this effect. For comparison, two electron sources, one with a spiral and a second with conventional rectangular (orthogonal) arranged emitters, were fabricated and investigated. Emission currents of 6 µA in the spiral ordered array and 120 µA in the rectangular array were reached with an extraction voltage of 400 V. From a mid-term measurement over 1 h a current stability of ±8.8 \% (spiral) respectively ±5.7 \% (rectangular) with a mean degradation of -3.0 µA/h (spiral) and -0.12 µA/h (rectangular) could be observed.}, language = {en} } @inproceedings{BuchnerBomkeHausladenetal., author = {Buchner, Philipp and Bomke, Vitali and Hausladen, Matthias and Edler, Simon and Bachmann, Michael and Schreiner, Rupert}, title = {Investigation on the Emission Behaviour of p-doped Silicon Field Emission Arrays with Individually Controllable Single Tips}, series = {2021 34th International Vacuum Nanoelectronics Conference (IVNC): 7/5/2021 - 7/9/2021, Lyon, France}, booktitle = {2021 34th International Vacuum Nanoelectronics Conference (IVNC): 7/5/2021 - 7/9/2021, Lyon, France}, publisher = {IEEE}, isbn = {978-1-6654-2589-6}, doi = {10.1109/IVNC52431.2021.9600756}, pages = {1 -- 2}, abstract = {Four individually controllable emission tips consisting of <111> p-Type silicon, were structured on a glass substrate by laser ablation. A matching extraction grid was manufactured in the same manner and aligned with the emitters. The resulting samples were characterized in ultra-high vacuum. As expected, the individual currents show a strong saturation and in the saturation region a considerably lower current fluctuation than n-type silicon due to charge carrier depletion. The individual tips behave completely independent behaviour from each other and the overall emission can be deduced from the sum of the currents through the individual tips.}, language = {en} } @inproceedings{HechtBauereiβSellmairetal., author = {Hecht, Fabian and Bauereiβ, Florian and Sellmair, Josef and Buchner, Philipp and Hausladen, Matthias and Schreiner, Rupert}, title = {Electron Beam Induced Growth of Carbon Nanotips on Tungsten and Silicon Fieldemitters}, series = {2023 IEEE 36th International Vacuum Nanoelectronics Conference (IVNC), 10-13 July 2023, Cambridge, MA, USA}, booktitle = {2023 IEEE 36th International Vacuum Nanoelectronics Conference (IVNC), 10-13 July 2023, Cambridge, MA, USA}, publisher = {IEEE}, isbn = {979-8-3503-0143-4}, doi = {10.1109/IVNC57695.2023.10188960}, pages = {160 -- 162}, abstract = {In our experiments we grew electron emitting carbon nanostructures on tungsten tips. Subsequently, we transferred the growth process to pre-structured phosphorus-doped n-type silicon and obtained emitting carbon nanostructures directly grown on silicon. After growth of the nanostructures, the silicon field emitters showed increased emission currents of 76 nA at 1.1 kV (compared to 6 nA under the same conditions before growth).}, language = {en} } @inproceedings{AllahamBuchnerSchreineretal., author = {Allaham, Mohammad M. and Buchner, Philipp and Schreiner, Rupert and Kn{\´a}pek, Alexandr}, title = {Testing the performance of Murphy-Good plots when applied to current-voltage characteristics of Si field electron emission tips}, series = {2021 34th International Vacuum Nanoelectronics Conference (IVNC): 5-9 July 2021, Lyon, France}, booktitle = {2021 34th International Vacuum Nanoelectronics Conference (IVNC): 5-9 July 2021, Lyon, France}, publisher = {IEEE}, doi = {10.1109/IVNC52431.2021.9600690}, pages = {1 -- 2}, abstract = {Murphy-Good plots are the most recent type of the analysis methods in the field electron emission theory, this type of plots has several useful characteristics such as: having the very-nearly straight line to represent the current-voltage characteristics and the absence of the correction factors in the mathematical procedure of the analysis process. In this study, n-type <111> and <100> Si chips containing four individual emitters are used as base emitters and mounted in a diode configuration field emission setup where the experiments are operated in an ultra-high vacuum ( 10-7 Pa). Each chip has four individual controllable emitters with 5 µm distance between the Si tips and the same material grid. Laser micromachining and subsequent wet chemical etching technique is used to structure and polish the tips. Murphy-Good plots are used to study the behavior of the Si individual tips and compare the results with the array current by extracting the field emission characterization parameters of the emitters.}, language = {en} } @inproceedings{BlahnikovaMuellerWaasetal., author = {Blahn{\´i}kov{\´a}, Barbora and M{\"u}ller, D. and Waas, M. and Lechner, Alfred}, title = {Multilyzer - microfluidic online measuring system for the analysis of environmentally relevant substances}, series = {AMA Conferences 2017 : Proceedings : SENSOR 2017 / N{\"u}rnberg 2017-05-30 - 2017-06-01}, booktitle = {AMA Conferences 2017 : Proceedings : SENSOR 2017 / N{\"u}rnberg 2017-05-30 - 2017-06-01}, publisher = {AMA Service GmbH}, address = {Wunstorf}, isbn = {978-3-9816876-4-4}, doi = {10.5162/sensor2017/P5.2}, pages = {696 -- 699}, language = {en} } @article{MelekhovPennWeidaueretal., author = {Melekhov, Evgeny and Penn, Tatjana and Weidauer, Tobias and Abb, Valerius and Kammler, Martin and Lechner, Alfred}, title = {Tunable nanopillar array on a quartz-fiber tip for surface enhanced Raman scattering (SERS) detection}, series = {tm - Technisches Messen}, volume = {89}, journal = {tm - Technisches Messen}, number = {1}, publisher = {de Gruyter}, doi = {10.1515/teme-2021-0093}, pages = {70 -- 81}, abstract = {In this work, a simple two-step method to create tunable self-assembled three-dimensional nanostructure array-like nanoantennas directly on the tip of an optical quartz glass fiber is described. The structures are prepared by using dry etching of the fiber tip. For the etching process, gold nanoparticles fabricated by thermal dewetting technique were used as template. The structures are applied as sensors for label-free analysis of organic substances in ppb range, such as drug residues in liquid solutions. The measurements are carried out by a portable Raman device with an exchangeable sensor head utilizing the SERS-effect. This method allows in situ applications. In order to characterize the SERS cells, para-thiocresol and diclofenac sodium are used as model substances. For optimization of the substrate performance, different thicknesses of the dewetting-layer (6, 9, 12 nm), different etching times for formation of the pillars (6, 8, 10 and 12 min), and different thicknesses of SERS-metallization (25, 50, 75 nm) of gold and silver are compared. In order to show the applicability of the structure on the tip of a fiber, measurements from the upper side and from the underside of the substrate on quartz plates are compared. Reproducible SERS enhancement factors up to 10 7 {10^{7}} were achieved.}, language = {en} } @incollection{BlahnikovaMuellerWaasetal., author = {Blahn{\´i}kov{\´a}, Barbora and M{\"u}ller, D. and Waas, M. and Lechner, Alfred}, title = {Multilyzer - Mikrofluidisches Echtzeitmesssystem f{\"u}r die Analyse umweltrelevanter Substanzen}, series = {7. MikroSystemTechnik Kongress "MEMS, Mikroelektronik, Systeme", 23.-25. Oktober 2017, M{\"u}nchen}, booktitle = {7. MikroSystemTechnik Kongress "MEMS, Mikroelektronik, Systeme", 23.-25. Oktober 2017, M{\"u}nchen}, publisher = {VDE-Verlag}, address = {M{\"u}nchen}, isbn = {978-3-8007-4491-6}, pages = {382 -- 385}, abstract = {Die {\"u}berm{\"a}ßige Verwendung von stickstoffbasierten D{\"u}ngemitteln in der Landwirtschaft stellt eine Gef{\"a}hrdung f{\"u}r die Umwelt und Lebewesen dar. So ist die Analyse von Boden- und Grundwasser zu einem wesentlichen Bestandteil der Nachhaltigkeit und der {\"o}kologischen Erhaltung geworden. Daf{\"u}r bietet der Multilyzer eine passende L{\"o}sung. Der Multilyzer ist ein mikrofluidisches Analysesystem zur Bestimmung niedrigster Konzentrationen von Nitrat, Nitrit und Ammonium, die alle wesentliche Bestandteile des Stickstoffkreislaufs sind. Welche bei {\"U}berm{\"a}ßiger Aufnahme im K{\"o}rper krebserregend wirken und den Sauerstofftransport im Blutkreislauf st{\"o}ren. Der Aufbau ist eine Kombination aus Absorptions- und Fluoreszenzspektroskopie. Der Betrieb mit einer 12 Volt Batterie erm{\"o}glicht die Verwendung des Multilyzer-Systems zur Online-Messung im Feld. Somit k{\"o}nnen sehr kurze Analysezeiten realisiert und der Einfluss von Umwandlungs- bzw. Abbauprozessen vermieden werden. Das gesamte Messsystem wird im Kompetenzzentrum Nanochem an der OTH Regensburg entwickelt, inklusive Fertigungstechnologien, Software- und Hardwaresteuerung.}, language = {de} } @inproceedings{BiekerRoustaieLangeretal., author = {Bieker, Johannes and Roustaie, Farough and Langer, Christoph and Schreiner, Rupert and Schlaak, Helmut F.}, title = {Innovatives Verfahren zur Herstellung und Integration metallischer Nanokonen f{\"u}r die Feldemission}, series = {MikroSystemTechnik Kongress 2017 : MEMS, Mikroelektronik, Systeme 23.-25. Oktober 2017 in M{\"u}nchen}, booktitle = {MikroSystemTechnik Kongress 2017 : MEMS, Mikroelektronik, Systeme 23.-25. Oktober 2017 in M{\"u}nchen}, number = {CD-ROM}, publisher = {VDE-Verlag}, address = {M{\"u}nchen}, isbn = {978-3-8007-4491-6}, pages = {797 -- 800}, abstract = {In den letzten Jahren wurde am Institut f{\"u}r Elektromechanische Konstruktionen die Fabrikation und Integration von metallischen Nanodr{\"a}hten und Nanokonen mittels Template-basierter Abscheidung erforscht. Diese Variante der in-situ Abscheidung von metallischen Nanostrukturen bietet eine Vielzahl von Anwendungsm{\"o}glichkeiten. Im Rahmen dieses Beitrags werden das Herstellungsverfahren zur Herstellung metallischer Nanokonen vorgestellt. Dies beinhaltet sowohl die Templatepr{\"a}paration mittels asymmetrischen {\"A}tzens als auch die anschließende Integration mittels galvanischer Abscheidung. Eine Anwendung der metallischen Nanokonen stellt die Verwendung als Feldemitter in der Vakuumelektronik dar. Es werden erste Messungen der Langzeitstabilit{\"a}t des Feldemissionsstromes der metallischen Konen pr{\"a}sentiert.}, language = {de} } @unpublished{AmatHalimahIshaketal., author = {Amat, A. and Halimah, M. K. and Ishak, M. and Nazrin, S. N. and Syamimi, Nik Nur and Hasnimulyati, L.}, title = {Electronic Polarizability and Optical Basicity of BaO-B2O3-TeO2 Glass System}, edition = {Version 1, posted 30 Nov, 2021}, doi = {10.21203/rs.3.rs-1093838/v1}, abstract = {[(TeO2)0.7(B2O3)0.3]1-x (BaO)x, x = 0.00, 0.05, 0.10, 0.20, 0.25, 0.30 and 0.35 mol fraction glass series were successfully synthesized by conventional melt quenching method. Amorphous phase of all samples was confirmed through X-ray diffraction while optical properties were determined using UV-VIS spectrophotometer. Fourier Transform Infrared (FTIR) analysis showed that the glass structure consisted of TeO3, TeO4, TeO6, BO3 and BO4 structural units. The optical band gap energy, Eopt which was calculated from Tauc' plots decreased as the amount of BaO increases, whereas, the Urbach energy value increased. The increase in Urbach energy value was attributed to the increase of defects in glass structure. The refractive indices of glass were found to increase along with the increased amount of BaO, due to the high polarization and high density of host material and glass modifier. The molar polarizability, αm, oxide ion polarizability, αo2- and optical basicity, Λ of the glasses are calculated by Lorentz-Lorenz equation. The glasses were found to possess αm values between 8.106 - 8.489 {\AA}3, and αo2- values between 3.303 to 4.772. Meanwhile, optical basicity increases from 0.115 to 0.893.

}, language = {en} } @inproceedings{RahimanBerndtSchreiner, author = {Rahiman, Mohd Fuad and Berndt, Dominik and Schreiner, Rupert}, title = {Micro-wire Pirani with temperature-stabilized Environment}, series = {3. Symposium Elektronik und Systemintegration ESI 2022: 06. April 2022, Hochschule Landshut}, booktitle = {3. Symposium Elektronik und Systemintegration ESI 2022: 06. April 2022, Hochschule Landshut}, isbn = {978-3-9818439-7-2}, pages = {52 -- 59}, language = {en} } @misc{Schreiner, author = {Schreiner, Rupert}, title = {Miniaturized sensor and actuator elements based on the heat transport in gases or the ionization of gas particles}, series = {16th International Conference on Optical and Electronic Sensors, COE'2020, 29 March - 2 April 2020, Krakow, Poland (online)}, journal = {16th International Conference on Optical and Electronic Sensors, COE'2020, 29 March - 2 April 2020, Krakow, Poland (online)}, language = {en} } @inproceedings{KleshchSerbunOrekhovetal., author = {Kleshch, Victor I. and Serbun, Pavel and Orekhov, Anton and L{\"u}tzenkirchen-Hecht, Dirk and Obraztsov, Alexander N. and Prommesberger, Christian and Langer, Christoph and Schreiner, Rupert and Lutzenkirchen-Hecht, Dirk}, title = {Field emission properties of p-type silicon tips decorated with tungsten nanoparticles}, series = {2017 30th International Vacuum Nanoelectronics Conference (IVNC), 10-14 July 2017, Regensburg, Germany}, booktitle = {2017 30th International Vacuum Nanoelectronics Conference (IVNC), 10-14 July 2017, Regensburg, Germany}, publisher = {IEEE}, doi = {10.1109/IVNC.2017.8051580}, pages = {138 -- 139}, abstract = {An array of conical-shaped p-type silicon tips was fabricated by using reactive ion etching and sharpening oxidation. The apex of each tip was decorated by a tungsten hemispherical nanoparticle. Field emission properties of the tips were measured by a tungsten-needle anode positioned above the tip apex. Tips decorated with tungsten nanoparticles demonstrated a smaller saturation region in current-voltage characteristics compared to the pristine tips. An emission activation process, which consisted in sudden current increase at certain value of applied voltage, was observed for the decorated silicon tips. This behavior was explained by the formation of vertical protrusions extending from the metal particles revealed by scanning electron microscopy after field emission experiments.}, language = {en} } @inproceedings{KnappLangerPrommesbergeretal., author = {Knapp, Wolfram and Langer, Christoph and Prommesberger, Christian and Lindner, Matthias and Schreiner, Rupert}, title = {Investigations of the transition from field electron emission to stable plasma discharge in a micro electron source at vacuum pressure}, series = {2017 30th International Vacuum Nanoelectronics Conference (IVNC), 10-14 July 2017, Regensburg, Germany}, booktitle = {2017 30th International Vacuum Nanoelectronics Conference (IVNC), 10-14 July 2017, Regensburg, Germany}, publisher = {IEEE}, doi = {10.1109/IVNC.2017.8051594}, pages = {166 -- 167}, abstract = {We report on the transition from field electron emission to plasma discharges. During an experiment with a miniaturized field emission electron source a plasma discharge accompanied by a luminous effect was observed. A novel graphical evaluation method was used to interpret and to compare the observed phenomenon.}, language = {en} } @inproceedings{HiyamaSehrYoshidaetal., author = {Hiyama, Toru and Sehr, Armin and Yoshida, Takahiro and Hangai, Seiichiro}, title = {Text/Language-Independent Unknown Speaker Rejection Method Using LSP Codes}, series = {IEEE 9th Global Conference on Consumer Electronics (GCCE 2020): 13-16 Oct. 2020, Kobe, Japan}, booktitle = {IEEE 9th Global Conference on Consumer Electronics (GCCE 2020): 13-16 Oct. 2020, Kobe, Japan}, doi = {10.1109/GCCE50665.2020.9291835}, abstract = {Scam phone calls pretending relatives have become a major social problem. However, current countermeasure against such scam phone calls stays only enlightenment activities although there is a limited number of technical measures in telephones. In this study, we have proposed a text-independent unknown speaker rejection method which recognizes whether a known speaker or an unknown speaker on receiving a call. In this method, we used a line spectral pair (LSP) spectrogram as the feature and a convolutional neural network (CNN) as the identification engine. From the evaluated results, the proposed method recognized known/unknown speakers with the false acceptance rate (FAR) of 13.1\% in Japanese speech and 25.2\% in German speech, respectively.}, language = {en} } @article{WalterSchwanzerHagenetal., author = {Walter, Stefanie and Schwanzer, Peter and Hagen, Gunter and Haft, Gerhard and Rabl, Hans-Peter and Dietrich, Markus and Moos, Ralf}, title = {Modelling the Influence of Different Soot Types on the Radio-Frequency-Based Load Detection of Gasoline Particulate Filters}, series = {Sensors}, volume = {20}, journal = {Sensors}, number = {9}, publisher = {MDPI}, doi = {10.3390/s20092659}, pages = {1 -- 19}, abstract = {Gasoline particulate filters (GPFs) are an appropriate means to meet today's emission standards. As for diesel applications, GPFs can be monitored via differential pressure sensors or using a radio-frequency approach (RF sensor). Due to largely differing soot properties and engine operating modes of gasoline compared to diesel engines (e.g., the possibility of incomplete regenerations), the behavior of both sensor systems must be investigated in detail. For this purpose, extensive measurements on engine test benches are usually required. To simplify the sensor development, a simulation model was developed using COMSOL Multiphysics((R)) that not only allowed for calculating the loading and regeneration process of GPFs under different engine operating conditions but also determined the impact on both sensor systems. To simulate the regeneration behavior of gasoline soot accurately, an oxidation model was developed. To identify the influence of different engine operating points on the sensor behavior, various samples generated at an engine test bench were examined regarding their kinetic parameters using thermogravimetric analysis. Thus, this compared the accuracy of soot mass determination using the RF sensor with the differential pressure method. By simulating a typical driving condition with incomplete regenerations, the effects of the soot kinetics on sensor accuracy was demonstrated exemplarily. Thereby, the RF sensor showed an overall smaller mass determination error, as well as a lower dependence on the soot kinetics.}, language = {en} } @article{WunderlichHauslerMaerkletal., author = {Wunderlich, Lukas and Hausler, Peter and Maerkl, Susanne and Bierl, Rudolf and Hirsch, Thomas}, title = {Nanoparticle Determination in Water by LED-Excited Surface Plasmon Resonance Imaging}, series = {Chemosensors}, volume = {9}, journal = {Chemosensors}, number = {7}, publisher = {MDPI}, issn = {2227-9040}, doi = {10.3390/chemosensors9070175}, pages = {1 -- 9}, abstract = {The increasing popularity of nanoparticles in many applications has led to the fact that these persistent materials pollute our environment and threaten our health. An online sensor system for monitoring the presence of nanoparticles in fresh water would be highly desired. We propose a label-free sensor based on SPR imaging. The sensitivity was enhanced by a factor of about 100 by improving the detector by using a high-resolution camera. This revealed that the light source also needed to be improved by using LED excitation instead of a laser light source. As a receptor, different self-assembled monolayers have been screened. It can be seen that the nanoparticle receptor interaction is of a complex nature. The best system when taking sensitivity as well as reversibility into account is given by a dodecanethiol monolayer on the gold sensor surface. Lanthanide-doped nanoparticles, 29 nm in diameter and with a similar refractive index to the most common silica nanoparticles were detected in water down to 1.5 mu g mL(-1). The sensor can be fully regenerated within one hour without the need for any washing buffer. This sensing concept is expected to be easily adapted for the detection of nanoparticles of different size, shape, and composition, and upon miniaturization, suitable for long-term applications to monitor the quality of water.}, language = {en} } @article{SchreinerSchweizer, author = {Schreiner, Rupert and Schweizer, Heinz C.}, title = {High-frequency operation of 1.57-μm laterally coupled distributed feedback lasers with self-aligned ohmic contacts and nickel surface gratings}, series = {IEEE Journal of Selected Topics in Quantum Electronics}, volume = {9}, journal = {IEEE Journal of Selected Topics in Quantum Electronics}, number = {5}, publisher = {IEEE}, doi = {10.1109/JSTQE.2003.819469}, pages = {1179 -- 1182}, abstract = {Laterally coupled distributed feedback lasers with self-aligned ohmic contacts show the advantage of a considerably simplified fabrication process. These lasers exhibit superior spectral properties with full benefit from the gain coupling mechanism. Side-mode suppression ratios up to 55- and 3-dB bandwidths beyond 15 GHz were obtained for these devices.}, language = {en} } @inproceedings{HauslerRothVitzthumeckeretal., author = {Hausler, Peter and Roth, Carina and Vitzthumecker, Thomas and Bierl, Rudolf}, title = {Miniaturized Surface Plasmon Resonance Based Sensor Systems}, series = {Optics, Photonics and Laser Technology 2018}, booktitle = {Optics, Photonics and Laser Technology 2018}, editor = {Ribeiro, Paulo and Raposo, Maria}, publisher = {Springer Nature}, address = {Cham}, isbn = {978-3-030-30112-5}, doi = {10.1007/978-3-030-30113-2_8}, pages = {169 -- 195}, abstract = {Surface Plasmon Resonance (SPR) is a well-known and established technology in bioanalysis and pharmaceutical sciences. Due to the expensive instrumentation and the need of trained people, it is mainly limited to applications in laboratories. However, there are some areas like environmental monitoring, chemical processing and civil infrastructure, which urgently need new sensor technologies. SPR has the potential to serve these fields. In order to be qualified for a use in these areas SPR has to overcome some hurdles. The instrumentation has to be robust, small in size and cheap. A device, which fits these needs, will be a micro-opto-electro-mechanical system (MOEMS) with integrated intelligent algorithms. In this book chapter, examples of miniaturized SPR devices are introduced, the limitations which have to be overcome as well as the possibilities for future applications are proposed. Due to the manifold advantages of this technology and the dropping prices for imaging sensors, Surface Plasmon Resonance imaging (SPRi) might become one of the leading technologies for SPR smart sensor systems.}, language = {en} } @incollection{SchwindlVolbertSchwab, author = {Schwindl, Tobias and Volbert, Klaus and Schwab, Maximilian}, title = {On Update Protocols in Wireless Sensor Networks}, series = {Sensor Networks}, booktitle = {Sensor Networks}, editor = {Benavente-Peces, C{\´e}sar and Cam-Winget, Nancy and Fleury, Eric and Ahrens, Andreas}, publisher = {Springer International Publishing}, address = {Cham}, isbn = {978-3-030-30109-5}, doi = {10.1007/978-3-030-30110-1_5}, pages = {74 -- 97}, abstract = {There has been a lot of research been done in the domain of Wireless Sensor Networks in recent years. Nowadays, Wireless Sensor Networks are in operation in a wide range of different scenarios and applications, like energy management services, heat and water billing as well as smoke detectors. However, research and development will be continued in this domain. During the operation of such a network, software updates need to be done seldom. In contrast to this, software updates need to be done very frequently during development and testing for uploading a new firmware on umpteen nodes. In this paper, we examine such a software update for a particular, but popular and often used sensor network platform. There are already interesting research papers about the process of updating sensor nodes. Our specific focus relies on the technical part of such an update process. We will argue why these already existing update processes do not cover our defiances. The objective of our software update protocol is to enable the developer to update many nodes in a reliable and very fast fashion during the development and testing process. For this reason, energy consumption is considered only marginally. We do not need a multi-hop protocol, due to the fact that all devices are in range, e.g. in a laboratory. In this paper we survey well known update protocols and architectures for software updates in WSN, discuss the solutions and compare them to our approach. As a conclusion of our extensive simulation follows to sum up that the developed protocols do a fast and scalable as well as a reliable update.}, language = {en} } @article{DamsSchreiner, author = {Dams, Florian and Schreiner, Rupert}, title = {Influencing factors on the sensitivity of MEMS-based thermal conductivity vacuum gauges}, series = {Journal of vacuum science \& technology A}, volume = {32}, journal = {Journal of vacuum science \& technology A}, number = {3}, publisher = {AVS}, doi = {10.1116/1.4867486}, abstract = {The measurement range of thermal conductivity vacuum gauges is mainly influenced by the sensitivity of the sensing element to variations in pressure. An enhanced definition of sensitivity shows its theoretical dependence on the geometric measures of the sensor element at the whole pressure range. This value gives the possibility of direct comparison between different types of sensor structures without the influence of the operating conditions. To study the influencing factors, sensor chips with heated surfaces in the order of some tens of mm 2 were realized by microelectromechanical systems-based fabrication techniques. By a silicon-glass hybrid process two cold planes were formed in a distance of 150 mu m above and below the heated element. The thermal conductance of devices with different geometric measures was determined in constant temperature operating mode by usage of embedded measurement equipment. In this configuration the sensor signals were sensitive to pressure in a region from 10(-5) mbar. The sensitivity was extracted by a fit of the theoretical model to the measurement data and showed the predicted dependencies on the geometric measures. (C) 2014 American Vacuum Society.}, language = {en} } @article{KieningerZechMulzeretal., author = {Kieninger, Martin and Zech, Nina and Mulzer, Yvonne and Bele, Sylvia and Seemann, Milena and K{\"u}nzig, Holger and Schneiker, Andr{\´e} and Gruber, Michael}, title = {Optimierung von Blutgasanalysen auf der Intensivstation. Reduzierung pr{\"a}analytischer Fehler und Verbesserung der zeitlichen Abl{\"a}ufe}, series = {Anaesthesist}, volume = {64}, journal = {Anaesthesist}, number = {5}, publisher = {Springer Nature}, doi = {10.1007/s00101-015-0024-8}, pages = {365 -- 372}, abstract = {Kontinuierliche Bem{\"u}hungen zur Vermeidung pr{\"a}analytischer Fehler und zur Optimierung der zeitlichen Abl{\"a}ufe bei der Blutgasanalyse (BGA) sind wichtig. In einer prospektiven Beobachtungsstudie wurde untersucht, ob durch Einf{\"u}hrung neuer, mit einem Strichcode versehener Probennehmer und von Analysatoren mit automatisierter Verarbeitung der Proben, verglichen mit dem bisherigen Vorgehen, Vorteile resultieren. In einer jeweils 4-w{\"o}chigen Testphase wurde f{\"u}r das herk{\"o}mmliche BGA-System (Kontrollgruppe) und unter Verwendung der neuen, mit einem Strichcode versehenen Probennehmer und automatischer Prozessierung der Blutproben (Testgruppe) die Zeitdauer bis zum Vorliegen der Ergebnisse bei Durchf{\"u}hrung einer BGA gemessen. Zudem wurde die H{\"a}ufigkeit pr{\"a}analytischer Fehler quantifiziert. Schließlich wurde untersucht, ob eine Liegedauer der Probennehmer von 10 min vor Vermessung der Probe Auswirkungen auf die resultierenden Ergebnisse des Sauerstoff- (pO2) und des Kohlendioxidpartialdrucks (pCO2) hat. In der Kontrollgruppe zeigten sich h{\"a}ufig pr{\"a}analytische Fehler (Vernachl{\"a}ssigen des Entl{\"u}ftens der Probennehmer und der Homogenisierung mithilfe des manuellen Schwenkens vor Beginn des Messvorgangs). Bei Analyse von BGA-Proben mit einer zeitlichen Latenz von 10 min nach Abnahme wurden in der Kontrollgruppe signifikant erh{\"o}hte pO2-Werte [Mittelwert (MW) 118,4 mmHg bei Messung unmittelbar nach Abnahme, MW 148,6 mmHg bei Messung mit 10-min-Latenz] und signifikant erniedrigte pCO2-Werte (40,5 vs. 38,3 mmHg) gemessen. In der Testgruppe zeigten sich signifikant erh{\"o}hte pO2-Werte (115,3 vs. 123,7 mmHg); die pCO2-Werte waren hier unver{\"a}ndert. Ein Zeitgewinn bis zum Vorliegen der Messergebnisse ließ sich in der Testgruppe nicht feststellen. Die Umstellung auf mit einem Strichcode versehene Probennehmer und automatisierte Verarbeitung der Blutproben am Analysator war im klinischen Alltag problemlos m{\"o}glich. Ein Zeitgewinn bei der BGA resultierte nicht. Allerdings waren Vorteile im Hinblick auf die Reduzierung pr{\"a}analytischer Fehler erkennbar. Eine verz{\"o}gerte Analyse von Blutproben kann, abh{\"a}ngig vom Typ des Probennehmers, zu signifikanten und klinisch relevanten Ver{\"a}nderung der Messwerte von pO2 und pCO2 f{\"u}hren. Point of care testing with blood gas analysis (BGA) is an important factor for intensive care medicine. Continuous efforts to optimize workflow, improve safety for the staff and avoid preanalytical mistakes are important and should reflect quality management standards. In a prospective observational study it was investigated whether the implementation of a new system for BGA using labeled syringes and automated processing of the specimens leads to improvements compared to the previously used procedure. In a 4-week test period the time until receiving the final results of the BGA with the standard method used in the clinical routine (control group) was compared to the results in a second 4-week test period using the new labeled syringes and automated processing of the specimens (intervention group). In addition, preanalytical mistakes with both systems were checked during routine daily use. Finally, it was investigated whether a delay of 10 min between taking and analyzing the blood samples alters the results of the BGA. Preanalytical errors were frequently observed in the control group where non-deaerated samples were recorded in 87.3 \% but in the intervention group almost all samples (98.9 \%) were correctly deaerated. Insufficient homogenization due to omission of manual pivoting was seen in 83.2 \% in the control group and in 89.9 \% in the intervention group; however, in the intervention group the samples were homogenized automatically during the further analytical process. Although a survey among the staff revealed a high acceptance of the new system and a subjective improvement of workflow, a measurable gain in time after conversion to the new procedure could not be seen. The mean time needed for a complete analysis process until receiving the final results was 244 s in the intervention group and 201 s in the control group. A 10-min delay between taking and analyzing the blood samples led to a significant and clinically relevant elevation of the values for partial pressure of oxygen (pO(2)) in both groups compared to the results when analyzing the samples immediately (118.4 vs. 148.6 mmHg in the control group and 115.3 vs. 123.7 mmHg in the intervention group). When using standard syringes the partial pressure of carbon dioxide (pCO(2)) was significantly lower (40.5 vs. 38.3 mmHg) whereas no alterations were seen when using the labeled syringes. The implementation of a new BGA system with labeled syringes and automated processing of the specimens was possible without any difficulties under daily clinical routine conditions in this 10-bed intensive care unit (ICU). A gain of time could not be measured but a reduction in preanalytical errors using the labeled syringes with automated processing was found. Delayed analysis of blood samples can lead to significant changes in pO(2) and pCO(2) depending on the type of syringe used.}, language = {de} } @article{SindersbergerDiermeierPremetal., author = {Sindersberger, Dirk and Diermeier, Andreas and Prem, Nina and Monkman, Gareth J.}, title = {Printing of hybrid magneto active polymers with 6 degrees of freedom}, series = {Materials today communications}, volume = {15}, journal = {Materials today communications}, number = {June}, publisher = {Elsevier}, doi = {10.1016/j.mtcomm.2018.02.032}, pages = {269 -- 274}, abstract = {3D printing techniques offer a versatile method for the fabrication and structuring of magnetoactive polymer (MAP) components and devices for research prototype development. MAP materials enjoy an advantage in that the particulate content may be manipulated by external magnetic fields during the forming and curing processes. Controlled particle diffusion within the polymer matrix, by means of external fields applied during the printing process, influences a further three spatial dimensions. This permits control of the spatial particle concentration and makes free displacement of particle accumulations possible during the crosslinking phase. Particles which are susceptible to electric or magnetic fields can thereby be shifted into regions previously free of particles. The additional 3 graded dispersion axes effectively results in what can be described as 6 degrees of freedom (6DOF) printing. Electrically conductive polymers combined with non-conductive areas, provide an additional benefit for the production of complex hybrid structures. This may be augmented by the combination of magnetically active thermoplastics as inelastic structural components together with mechanically deformable elastomers. The combination of all fabrication methods in one hybrid printing process makes the production of complex sensor and actuator systems in one manufacturing sequence possible. This far exceeds the capabilities of conventional casting and machining operations and opens new possibilities for the fabrication of soft material elements.}, language = {en} } @article{AgranovskyBomanHasanovetal., author = {Agranovsky, Mark and Boman, Jan and Hasanov, Alemdar and Felea, Raluca and Frikel, J{\"u}rgen and Krishnan, Venky and Novikov, Roman and Ramlau, Ronny and Sebu, Cristiana}, title = {Research biography of a distinguished expert in the field of inverse problems: Professor Eric Todd Quinto}, series = {Journal of Inverse and Ill-posed Problems}, volume = {30}, journal = {Journal of Inverse and Ill-posed Problems}, number = {4}, publisher = {De Gruyter}, issn = {1569-3945}, doi = {10.1515/jiip-2022-0031}, pages = {613 -- 617}, abstract = {This article gives a brief overview of the research in microlocal analysis, tomography, and integral geometry of Professor Eric Todd Quinto, Robinson Professor of Mathematics at Tufts University, along with the collaborators and colleagues who influenced his work.}, language = {en} } @inproceedings{SchwindlVolbertBock, author = {Schwindl, Tobias and Volbert, Klaus and Bock, Sebastian}, title = {Fast and Reliable Update Protocols in WSNs During Software Development, Testing and Deployment}, series = {Proceedings of the 7th International Conference on Sensor Networks - SENSORNETS, Funchal, January 22-24, 2018, Madeira, Portugal}, booktitle = {Proceedings of the 7th International Conference on Sensor Networks - SENSORNETS, Funchal, January 22-24, 2018, Madeira, Portugal}, editor = {Fleury, Eric and Ahrens, Andreas and Benavente-Peces, C{\´e}sar and Cam-Winget, Nancy}, publisher = {SCITEPRESS - Science and Technology Publications Lda}, address = {Set{\´u}bal, Portugal}, organization = {Institute for Systems and Technologies of Information, Control and Communication}, isbn = {978-989-758-284-4}, doi = {10.5220/0006534400190030}, pages = {19 -- 30}, abstract = {A lot of research has been done in the area of Wireless Sensor Networks during the past years. Today, Wireless Sensor Networks are in field in many different ways and applications (e.g. energy management services, heat and water billing, smoke detectors). Nevertheless, research and development is continued in this area. After the network is deployed, software updates are performed very rarely, but during development and testing one typical, high frequented task is to deploy a new firmware to thousands of nodes. In this paper, we consider such a software update for a special, but well-known and frequently used sensor network platform. There exist some interesting research papers about updating sensor nodes, but we have a special focus on the technical update process. In this context, we show the reasons why these existing update processes do not cover our challenges. Our goal is to allow a developer to update thousands of nodes reliably and very fast during development and testing. Fo r this purpose, it is not so important to perform the best update with regard to energy consumption. We do not need a multi hop protocol, because all devices are in range, e.g., in a laboratory. In our work, we present a model of the update process and give very fast protocols to solve it. The results of our extensive simulations show that the developed protocols do a fast, scalable and reliable update.}, language = {en} } @article{KurzweilShamoninChamonineUdalzow, author = {Kurzweil, Peter and Shamonin (Chamonine), Mikhail and Udalzow, Anton}, title = {Selbstentladung und Leckstromverhalten elektrochemischer Speicher: Impedanzspektroskopie im Langzeitversuch}, series = {Forschungsbericht 2016 / OTH Amberg-Weiden}, journal = {Forschungsbericht 2016 / OTH Amberg-Weiden}, publisher = {Ostbayerische Technische Hochschule Amberg-Weiden}, issn = {2365-1997}, pages = {90 -- 94}, abstract = {Doppelschichtkondensatoren sind elektrochemische Speicher, die innerhalb von Mikrosekunden auf schnelle Last{\"a}nderungen antworten. Auf der Basis einer mehr als zehnj{\"a}hrigen Testerfahrung unserer Arbeitsgruppe sind wir in der Lage, das Alterungsverhalten von Superkondensatoren anhand von Kapazit{\"a}tsverlust, parasit{\"a}ren Nebenreaktionen und der chemischen Analyse von Alterungsprodukten zu quantifizieren. Weitgehend ungekl{\"a}rt sind die elektrochemischen Mechanismen bei der Selbstentladung der Bauteile, die wir nun mithilfe der Impedanzspektroskopie n{\"a}her untersucht haben . Double-layer capacitors are electrochemical storage devices that are able to respond to immediate load changes within some microseconds. Based on more than ten years testing experience of our work group, the aging behaviour of supercapacitors is quantified in terms of capacitance loss, parasitic side reactions, and the chemical analysis of decomposition products. So far, the electrochemical processes during self-discharge have been widely unknown. By the help of impedance spectroscopy, we investigated this item in more detail.}, language = {de} } @article{SykoraHolickyDiamantidis, author = {S{\´y}kora, Miroslav and Holick{\´y}, Milan and Diamantidis, Dimitris}, title = {Probabilistic updating in the reliability assessment of industrial heritage structures}, series = {Heron}, volume = {59}, journal = {Heron}, number = {2/3}, publisher = {Stevin-Laboratorium, TU Delft}, address = {Delft}, issn = {0046-7316}, abstract = {Assessment of existing structures should be based on the actual as-built conditions concerning geometry, material properties, loading and environmental conditions. A crucial step of the assessment consists in updating of prior information by newly obtained measurements which may be conducted by Bayesian approach. Updating of probabilistic distributions of basic variables or direct updating of failure probability can be effectively used. Application of theoretical principles is illustrated by a case study of a historic factory built in 1900s. The paper is a tribute to Ton Vrouwenvelder for his essential contributions to developments of theory and promotion of practical applications of probabilistic assessment of existing structures.}, language = {en} } @inproceedings{ShamoninChamonineDechantFedulovetal., author = {Shamonin (Chamonine), Mikhail and Dechant, Eduard and Fedulov, Feodor and Fetisov, Leonid Y.}, title = {Bandwidth optimization of piezoelectric cantilever beam arrays for harvesting energy from broadband, low-frequency mechanical vibrations}, series = {INTERMATIC 2016, 21.-25.11.2016, Moskau}, volume = {16}, booktitle = {INTERMATIC 2016, 21.-25.11.2016, Moskau}, address = {Moskau}, pages = {187 -- 190}, language = {en} } @inproceedings{DegueldreWaasKucera, author = {Degueldre, Dennis and Waas, Thomas and Kucera, Markus}, title = {Electromagnetic Emission of an Optical-to-BroadR-Reach Converter}, series = {Proceedings of the 4th International Conference on Pervasive and Embedded Computing and Communication Systems (PECCS), 2014, Lisbon, Portugal}, booktitle = {Proceedings of the 4th International Conference on Pervasive and Embedded Computing and Communication Systems (PECCS), 2014, Lisbon, Portugal}, isbn = {978-989-758-000-0}, issn = {2184-2817}, doi = {10.5220/0004711401310135}, pages = {131 -- 135}, abstract = {The automotive solution for Ethernet is BroadR-Reach, which cannot be found as a common Ethernet-interface in the consumer industry. Hence a media converter from IEEE 802.3 Ethernet to BroadR-Reach is needed to debug and test the communication of automotive devices under test (DUT). If the functionality of a BroadR-Reach connection has to be tested for electromagnetic compatibility (EMC), a BroadR-Reach to optical media converter is needed, which has to comply to the same EMC test specifications as the DUT. This research explains the internal structure of a media converter and defines a test setup for copper bound emission test of BroadR-Reach. By using a standardized stripline measurement like it is common for electromagnetic emission test, it could be shown, that the tested Technica/Tinytron media converter can safely be used inside an EMC chamber.}, language = {en} } @article{PetcharteeMonkman, author = {Petchartee, Somrak and Monkman, Gareth J.}, title = {Optimisation of Prehension Force through Tactile Sensing}, series = {Industrial Robot}, volume = {35}, journal = {Industrial Robot}, number = {4}, publisher = {MCB Univ. Press}, address = {Bradford}, doi = {10.1108/01439910810876454}, pages = {361 -- 368}, abstract = {Purpose The purpose of this paper is to analyze surface deformations caused by shear and moment forces on tactile materials and present a method to detect and reduce the risk of slippage by controlling the normal force as measured by tactile sensor arrays. Design/methodology/approach A predictive model has been proposed which uses a basic method adapted to real applications in grasp optimization. Prevention of premature release with minimum prehension force is addressed without the need to measure the coefficient of friction between object and robot gripper. Predictive models have been used to develop a set of rules which predict the pre-slip based on fluctuations in tactile signal data. Findings The tactile sensors can be used in a "nonlinear" manner during manipulation tasks. When the gripper finger first makes contact with an object, the stress distribution under the finger skin varies rapidly. Predictive models have been used to develop a set of rules which predict the pre-slip based on fluctuations in tactile signal data. Pre-slip at the contact area just prior to object movement produces rapid but detectable stress transients. Originality/value Tactile sensors do not measure stress generated by a contact with an object directly, but instead measure strain in an interposed compliant, polymeric medium intended for sensor protection and prehension assistance. Reliable detection of pre-slip has hitherto eluded researchers using such tactile techniques.}, language = {en} } @incollection{PetcharteeMonkmanSuebsromran, author = {Petchartee, Somrak and Monkman, Gareth J. and Suebsromran, Anan}, title = {3D-Shape Recognition based Tactile Sensor}, series = {Smart Sensors and Sensing Technology}, booktitle = {Smart Sensors and Sensing Technology}, editor = {Mukhopadhyay, S.C. and Gupta, G.S.}, publisher = {Springer}, address = {Berlin ; Heidelberg}, isbn = {978-3-540-79589-6}, doi = {10.1007/978-3-540-79590-2_21}, pages = {317 -- 332}, abstract = {A surface recognition algorithm capable of determining contact surfaces types by means of tactile sensor fusion is proposed. The authors present a recognition processes for 3-dimensional deformations in a 2-dimensional parametric domain. Tactile information is extracted by physical contact with a grasped object through a sensing medium. Information is obtained directly at the interface between the object and the sensing device and relates to three-dimensional position and orientation of the object in the presence of noise. The technique called "eigenvalue trajectory analysis", is introduced and adopted for specifying the margin of classification and classification thresholds. The authors demonstrate mathematically that this approach, which complements existing work, offers significant computational advantages when applied to challenging contact scenarios such as dynamic recognition of contact deformations.}, language = {en} } @inproceedings{PetcharteeMonkman, author = {Petchartee, Somrak and Monkman, Gareth J.}, title = {3D-Shape Recognition based Tactile Sensor}, series = {ICST 2007, Proceedings of 2nd International Conference on Sensing Technology : Massey University, Palmerston North, New Zealand, November 26 - 28, 2007}, booktitle = {ICST 2007, Proceedings of 2nd International Conference on Sensing Technology : Massey University, Palmerston North, New Zealand, November 26 - 28, 2007}, publisher = {Inst. of Information Sciences and Techn., Massey Univ.}, address = {Palmerston}, pages = {56 -- 61}, language = {en} } @article{PetcharteeMonkman, author = {Petchartee, Somrak and Monkman, Gareth J.}, title = {Pre-slip Sensing through Tactile Sensing}, series = {Sensors \& Transducers}, volume = {90}, journal = {Sensors \& Transducers}, number = {4, Special Issue}, publisher = {International Frequency Sensor Association (IFSA)}, issn = {1726-5479}, pages = {310 -- 324}, language = {en} } @inproceedings{PetcharteeMonkman, author = {Petchartee, Somrak and Monkman, Gareth J.}, title = {Contact Identification using Tactile Arrays}, series = {Proceedings of the 7th IEEE International Symposium on Signal Processing and Information Technology (ISSPIT 2007), 15.-18.12.2007, Giza, Egypt}, booktitle = {Proceedings of the 7th IEEE International Symposium on Signal Processing and Information Technology (ISSPIT 2007), 15.-18.12.2007, Giza, Egypt}, publisher = {IEEE}, doi = {10.1109/ISSPIT.2007.4458144}, pages = {1121 -- 1126}, abstract = {The proposed method allows a robot to quantify tactile recognition of grasped objects. The responses by the robot are matched by randomly introducing objects following the completion of tactile sensor based training phases on 4 specific objects. The reproduction of the robotic contact identification is accomplished by matching threshold values of the smallest eigenvalue of the Quadric surface - called the eigenvalue trajectory. Once the grasped objects are introduced to the 2-fingered robot hand, the eigenvalue trajectory of contact surfaces are calculated by the system. Calculations are based on the degree of similarity of the characteristics between the newly received and previously trained tactile data. Experimental results indicate that the proposed algorithm allows a successful quantification of robotic contact recognition and the accomplishment of high levels of accuracy in contact identification. These results confirm that the proposed method is useful for identifying contact surfaces based on tactile sensor data.}, language = {en} } @inproceedings{PetcharteeMonkman, author = {Petchartee, Somrak and Monkman, Gareth J.}, title = {Contact Classification using Tactile Arrays}, series = {2007 3rd International Conference on Intelligent Sensors, Sensor Networks and Information (ISSNIP), 3, 03.-06.12.2007, Melbourne, VIC, Australia}, booktitle = {2007 3rd International Conference on Intelligent Sensors, Sensor Networks and Information (ISSNIP), 3, 03.-06.12.2007, Melbourne, VIC, Australia}, doi = {10.1109/ISSNIP.2007.4496848}, pages = {227 -- 232}, abstract = {This paper proposed a contact recognition algorithm capable of determining contact surfaces types by tactile sensor fusion. This algorithm can recognize grasped objects using a 2- fingered robot hand, on which tactile sensors are mounted. Experiments have demonstrated reliable surface classification and accurate transformation independent of object shape and orientation. The contribution of this paper regards the relations between a surface and the points cloud defining it. Particularly, we investigate on the possibility that there is some intrinsic feature of a points cloud under quadric surface, allowing us to discriminate or classify a dataset defining a surface from the acquisition noise.}, language = {en} } @article{PetcharteeMonkman, author = {Petchartee, Somrak and Monkman, Gareth J.}, title = {Contact Recognition using Tactile Sensor}, series = {Annals Universitaria Craiova-Series: Automation, Computers, Electronics and Mechatronics}, volume = {4 (31)}, journal = {Annals Universitaria Craiova-Series: Automation, Computers, Electronics and Mechatronics}, number = {2}, pages = {103 -- 108}, abstract = {The surface recognition algorithm that determines the types of contact surfacesby fusing information collected by the tactile sensor system is proposed. The tactilesystem will be determined from the shape of the object image which can then becharacterized using the mathematical properties of Quadric surface. This algorithm canrecognize 3-D objects using a 2-fingered robot gripper, on which tactile sensors aremounted. Experiments have demonstrated the reliability of the surface classificationmethod and the accuracy of transformations independent of an object's shape, translationand rotation.}, language = {en} } @article{PetcharteeMonkman, author = {Petchartee, Somrak and Monkman, Gareth J.}, title = {Optimisation of Prehension Force through Tactile Sensing}, series = {Journal of Advanced Manufacturing Technology}, journal = {Journal of Advanced Manufacturing Technology}, publisher = {Universiti Teknikal Malaysia Melaka}, issn = {2289-8107}, language = {en} } @article{PetcharteeMonkman, author = {Petchartee, Somrak and Monkman, Gareth J.}, title = {Contact Recognition through Tactile Sensing}, series = {ACTA Universitatis Apulensis; Seria Mathematics-Informatics}, journal = {ACTA Universitatis Apulensis; Seria Mathematics-Informatics}, publisher = {Department of Mathematics and Informatics}, address = {Alba Iulia}, issn = {1582-5329}, language = {en} } @inproceedings{PetcharteeMonkman, author = {Petchartee, Somrak and Monkman, Gareth J.}, title = {Contact Recognition using Tactile Sensor}, series = {Proc. International Symposium on System Theory, Automation, Robotics, Computers, Informatics, Electronics and Instrumentation (SINTES13), Romania}, booktitle = {Proc. International Symposium on System Theory, Automation, Robotics, Computers, Informatics, Electronics and Instrumentation (SINTES13), Romania}, pages = {285 -- 290}, language = {en} } @inproceedings{PetcharteeMonkman, author = {Petchartee, Somrak and Monkman, Gareth J.}, title = {Pre-slip detection based Tactile Sensing}, series = {Proc. 3rd International Conference on Intelligent Sensors, Sensor Networks and Information Processing (ISSNIP 2007), Melbourne}, booktitle = {Proc. 3rd International Conference on Intelligent Sensors, Sensor Networks and Information Processing (ISSNIP 2007), Melbourne}, pages = {233 -- 238}, language = {en} } @inproceedings{PetcharteeMonkman, author = {Petchartee, Somrak and Monkman, Gareth J.}, title = {Contact classification using tactile arrays}, series = {Proc. International Conference on Engineering \& ICT 2007 (ICEI 2007), 27th to 29th November 2007, Malacca, Malaysia}, booktitle = {Proc. International Conference on Engineering \& ICT 2007 (ICEI 2007), 27th to 29th November 2007, Malacca, Malaysia}, language = {en} } @inproceedings{PetcharteeMonkman, author = {Petchartee, Somrak and Monkman, Gareth J.}, title = {Optimisation of Prehension Force through Tactile Sensing}, series = {Proc. International Conference on Engineering \& ICT 2007 (ICEI 2007), Malaysia}, booktitle = {Proc. International Conference on Engineering \& ICT 2007 (ICEI 2007), Malaysia}, language = {en} } @article{PetcharteeMonkman, author = {Petchartee, Somrak and Monkman, Gareth J.}, title = {Slip Prediction through Tactile Sensing}, series = {Sensors \& Transducers}, volume = {90}, journal = {Sensors \& Transducers}, number = {Special Issue April 2008}, publisher = {International Frequency Sensor Association, IFSA}, issn = {1726-5479}, pages = {310 -- 324}, abstract = {This paper introduces a new way to predict contact slip using a resistive tactile sensor. The prototype sensor can be used to provide intrinsic information relating to geometrical features situated on the surface of grasped objects. Information along the gripper finger surface is obtained with a measurement resolution dependant on the number of discrete tactile elements. The tactile sensor predicts the partial slip of a tactile surface by sensing micro vibrations in tangential forces which are caused by an expansion of the slip regions within the contact area. The location of the local slip is not specified but its occurrence can be predicted immediately following micro vibration detection. Predictive models have been used to develop a set of rules which predict the slip based on fluctuations in tactile signal data.  }, language = {en} } @inproceedings{PetcharteeMonkman, author = {Petchartee, Somrak and Monkman, Gareth J.}, title = {Pre-slip sensing using tactile sensor}, series = {Proceedings / SINTES 13, International Symposium on Systems Theory, Automation, Robotics, Computers, Informatics, Electronics and Instrumentation, October 18 - 20, 2007, Craiova - Romania}, booktitle = {Proceedings / SINTES 13, International Symposium on Systems Theory, Automation, Robotics, Computers, Informatics, Electronics and Instrumentation, October 18 - 20, 2007, Craiova - Romania}, pages = {279 -- 284}, language = {en} } @article{PetcharteeMonkman, author = {Petchartee, Somrak and Monkman, Gareth J.}, title = {Pre-slip sensing using tactile sensor}, series = {Annals Universitaria Criaiova-Series: Automation, Computers, Electronics and Mechatronics}, volume = {4 (31)}, journal = {Annals Universitaria Criaiova-Series: Automation, Computers, Electronics and Mechatronics}, number = {2}, pages = {109 -- 114}, language = {en} } @inproceedings{PetcharteeMonkman, author = {Petchartee, Somrak and Monkman, Gareth J.}, title = {Pre-slip Sensing through Tactile Sensing}, series = {Proc. 2nd International Conference on Sensing Technology (ICST 2007), New Zealand}, booktitle = {Proc. 2nd International Conference on Sensing Technology (ICST 2007), New Zealand}, pages = {62 -- 67}, language = {en} } @article{LangerBerndtSchreiner, author = {Langer, Christoph and Berndt, Dominik and Schreiner, Rupert}, title = {Sensitivity of thermal conductivity vacuum gauges for constant current and constant temperature operation}, series = {Journal of Vacuum Science and Technology B: Nanotechnology and Microelectronics}, volume = {40}, journal = {Journal of Vacuum Science and Technology B: Nanotechnology and Microelectronics}, number = {5}, publisher = {AIP Publishing}, doi = {10.1116/6.0001964}, abstract = {To optimize the measurement range of thermal conductivity vacuum gauges, an expression for the sensitivity is required that takes into account all geometrical, material-specific, and operating parameters. Therefore, equations of the sensor output signal as a function of the pressure for the constant current and the constant temperature mode have been developed analytically. Based on these equations, the sensitivity of the vacuum gauge and its influencing parameters was investigated and discussed. For comparable conditions, the constant temperature operation shows a significantly higher sensitivity for high pressures, while the constant current operation shows higher sensitivity at low pressures. The sensitivity in both the constant current and the constant temperature mode depends on the ratio of the filament surface area and the parasitic thermal conductance. In addition, for the constant current operation, the sensitivity also depends on the current value and the temperature coefficient of the filament resistor. For the constant temperature operation, the sensitivity additionally depends on the distance of the filament and the reference plane. However, to extend the measurement range of a thermal conductivity vacuum gauge toward low pressures, a reduction of the parasitic thermal conductance is mandatory for both the constant current and the constant temperature mode.}, language = {en} } @unpublished{RueckMuellerJobstetal., author = {R{\"u}ck, Thomas and M{\"u}ller, Max and Jobst, Simon and Weigl, Stefan and Pangerl, Jonas and Bierl, Rudolf and Matysik, Frank-Michael}, title = {Digital Twin of a Photoacoustic Trace Gas Sensor for Monitoring Methane in Complex Gas Compositions}, publisher = {Elsevier / SSRN}, doi = {10.2139/ssrn.4215170}, pages = {22}, abstract = {The digitalization of industrial processes requires smart sensor systems. Photoacoustic spectroscopy is well suited for this purpose as it allows for small-sized and low-cost trace gas analysis. However, the method is susceptible to changes in measurement conditions and standard calibration routines often fail to correct for all changes. We therefore created a Digital Twin (DT) of a photoacoustic trace gas sensor for methane and evaluated it regarding variations in gas composition (CH4, N2, O2, CO2, H2O), temperature and pressure. With a mean absolute percentage error of 0.8 \% the accuracy of the sensor after DT compensation significantly exceeds the 24 \% achieved based on standard calibration in nitrogen. For the first time, we can fully analytically compute the photoacoustic signal under moderate ambient conditions with an error in the ppbV range by taking a holistic approach. Assuming knowledge of the underlying energy transfer processes, the model of this Digital Twin can be adapted to any microphone based photoacoustic sensor for monitoring any analyte species.}, language = {en} }