TY - INPR A1 - Steffens, Oliver T1 - The Media Revolution in the 19th Century: How Sound Recording, Motion Pictures and Writing Machines affected human perception, thinking, and our society until today N2 - Which influence had the sudden appearance of sound recording, film, and typewriters at the end of the 19th century on the human perception of and our thinking about what we consider “reality”? How did our society change with these technological innovations? After millennia of speech and the culture of writing, a fundamental disruption occurred when Thomas Alva Edison introduced his “phonograph” in 1877. In his book “Grammophon, Film, Typewriter” (Brinkmann & Bose, Berlin 1986), Friedrich Kittler (1943-2011) discusses this question from his perspective as literary scholar and media theorist, reviewing contemporary authors to let them bear witness to their experiences and impressions of the then-new media. This essay intends to be a short extract of Kittler’s book, meandering between additional sources of historians, writers, commentators, yet always coming back to Kittler’s fascinating panopticon. KW - History of technology KW - cultural impact KW - film KW - sound recording KW - typewriter KW - gramophone KW - motion picture KW - media KW - literature Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-58376 CY - Regensburg ER - TY - INPR A1 - Steffens, Oliver T1 - Leibniz, Llull and the Logic of Truth: Precursors of Artificial Intelligence N2 - Mankind has always been confronted with limited knowledge about Nature and many people devoted their lives and intellects to the very question: How to gain knowledge, confirm ideas and theories, and understand the world we live in? Religion was one fundamental base for explanations and existential questions. Philosophy and Science were the other. Nowadays, science and technology dominate our daily lives, religion and metaphysics have lost their former dominance, while our thoughts and factual knowledge are increasingly governed by the digitised versions of conversation and discussion, filtered and guided by the algorithms of social networks. Today, "artificial intelligence" is a phenomenon in information technology which takes over everyday routines. A new ideal, a new promise, and at the same time used as a stratagem by political and economic systems to guide and manipulate our thinking, values, and behaviour. But nothing is so new that one could not find its precursors in earlier times. Science and mathematics has kindled many brilliant ideas. Can we describe the world by numbers, find truth and explanation in mathematical structures? This essay is devoted to early ideas by the medieval philosopher Ramón Llull, the great rationalist G.W. Leibniz, and early approaches to combinations, number theory. and information processing. Llull's thinking machine and subsequent endeavours to find methods of mechanical reasoning and inference paved the way to modern-day concepts of artificial intelligence. KW - artificial intelligence KW - Leibniz KW - Ramón Llull KW - thinking machine KW - combinatorics KW - number theory KW - Giordano Bruno KW - Turing machine KW - Ars Magna KW - logic Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:898-opus4-58399 CY - Regensburg ER - TY - INPR A1 - Menzel, Andreas A1 - Yeh, Wang-Chi Vincent A1 - Kammler, Martin A1 - Hupalo, Myron A1 - Conrad, E. H. A1 - Tringides, Michael C. T1 - Measurements of the kinetic barriers controlling the formation of the uniform height islands in Pb/Si(111) N2 - As demonstrated with SPA-LEED and STM uniform height islands of preferred thickness form during the growth of Pb on Si(111). The islands form at temperatures T<250K and for fluxes F 1/60ML/sec which requires fast kinetics and balance between several atomic processes: diffusion towards the islands , diffusion to higher layers and preference for the atoms to remain on top of the preferred height islands. We have carried out SPA-LEED experiments to measure the barriers of the processes: we prepare an initial predominantly 5-step island height distribution and we deposit an additional 0.5ML Pb at different growth temperatures Tg to determine the transition to the next preferred height of 7-step islands (i.e. 2-step islands on top of the 5-step islands) with Spot Profile Analysis(SPA-LEED). We observe that 7-step island formation is possible above a minimum temperature Tg*=175K which indicates that the transfer of atoms from the surrounding region to the top of the islands is the main controlling process. Y1 - 2002 UR - https://www.researchgate.net/publication/259264144_Measurements_of_the_kinetic_barriers_controlling_the_formation_of_the_uniform_height_islands_in_PbSi111 ER - TY - INPR A1 - Cavalleri, Andrea A1 - Siders, Craig A1 - Toth, Csaba A1 - Squier, Jeff A. A1 - Barty, C. P. J. A1 - Wilson, K. R. A1 - Sokolowski-Tinten, Klaus A1 - von der Linde, Dietrich A1 - Kammler, Martin A1 - Horn- von Hoegen, Michael T1 - Measurement of harmonic and anharmonic semi-conductor-lattice dynamics with ultrafast x-ray diffraction N2 - Many fundamental processes in solids, such as heat transport and phase transitions involve atomic movement on ultrafast time-scales, but cannot be directly measured with visible light. Using ultrafast x-ray diffraction, atomic motion can be measured on its natural time-scale. Photo-excitation of bulk and layered semiconductors was achieved with 800-nm wavelength femtosecond laser pulses. Optical excitation triggers a chain of relaxation processes, causing rapid lattice heating, generation and propagation of stress/strain waves into the bulk and eventual anharmonic decay of coherent acoustic phonons into the thermal bath of the solid. While the first steps of carrier relaxation, excitation and decay of Raman-active optical phonons have been in the past characterized optically at surfaces, the bulk acoustic dynamics at longer times has not. We measure length scales of lattice excitation, thereby detecting ultrafast heat diffusion via fast electrons, coherent acoustic pulse propagation into the bulk or across buried interfaces and anharmonic damping of non-equilibrium acoustic phonons. The measurement is performed with sensitivity on lattice spacing of 10 femtometers (i.e., 3 nuclear diameters). Y1 - 2000 UR - https://www.researchgate.net/publication/252175863_Measurement_of_harmonic_and_anharmonic_semi-conductor-lattice_dynamics_with_ultrafast_x-ray_diffraction ER - TY - INPR A1 - Siders, Craig A1 - Cavalleri, Andrea A1 - Toth, Csaba A1 - Squier Jeff A., A1 - Barty, C. P. J. A1 - Wilson, K. R. A1 - Sokolowski-Tinten, Klaus A1 - von der Linde, Dietrich A1 - Kammler, Martin A1 - Horn- von Hoegen, Michael T1 - Ultrafast Nonthermal Melting of Femtosecond-laser-irradiated Germanium Measured by Ultrafast X-ray Diffraction N2 - Many fundamental processes in nature, such as chemical reactions and phase transitions involve rearrangement of the constituent atoms. Such changes cannot be directly measured with visible light and occur transiently on time-scales comparable with the natural oscillation periods of atoms (femtoseconds to picoseconds). We present experiments on Ge-111 films irradiated with 100-fs 800-nm light pulses and probed by a time-delayed sub-ps x-ray pulse at 8 keV. After excitation of a dense electron-hole plasma within the 160-nm film, the ultrafast pathway of lattice disordering is measured as a function laser fluence. For close-to-threshold irradiation, inhomogeneous thermal melting, occurring via surface nucleation of the liquid phase and growth into the bulk determines the dynamics of the solid-to-liquid phase transition. For excitation at about twice the melting threshold, a nonthermal pathway, starting from a highly excited cold solid and relaxing into a hot liquid causes ultrafast melting. At long time delays, nearly perfect recrystallization of a (111) crystal is observed. Y1 - 2000 UR - https://www.researchgate.net/publication/252159566_Ultrafast_Nonthermal_Melting_of_Femtosecond-laser-irradiated_Germanium_Measured_by_Ultrafast_X-ray_Diffraction ER - TY - INPR A1 - Steffens, Oliver T1 - Nomograms for Quadratic and Cubic Equations Y1 - 2024 U6 - https://doi.org/10.13140/RG.2.2.12187.48168 ER - TY - INPR A1 - Pangerl, Jonas A1 - Sukul, Pritam A1 - Rück, Thomas A1 - Fuchs, Patricia A1 - Weigl, Stefan A1 - Miekisch, Wolfram A1 - Bierl, Rudolf A1 - Matysik, Frank-Michael T1 - An Inexpensive Uv-Led Photoacoustic Based Real-Time Sensor-System Detecting Exhaled Trace-Acetone N2 - 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. KW - photoacoustic spectroscopy KW - real-time mass-spectrometry KW - breath analysis KW - acetone KW - UV-LED Y1 - 2024 U6 - https://doi.org/10.2139/ssrn.4724198 N1 - Der Aufsatz wurde peer-reviewed unter folgender DOI veröffentlicht: https://doi.org/10.1016/j.pacs.2024.100604 PB - Elsevier ER - TY - INPR A1 - Amat, A. A1 - Halimah, M. K. A1 - Ishak, M. A1 - Nazrin, S. N. A1 - Syamimi, Nik Nur A1 - Hasnimulyati, L. T1 - Electronic Polarizability and Optical Basicity of BaO-B2O3-TeO2 Glass System N2 - [(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 Å3, and αo2- values between 3.303 to 4.772. Meanwhile, optical basicity increases from 0.115 to 0.893.

Y1 - 2021 U6 - https://doi.org/10.21203/rs.3.rs-1093838/v1 ET - Version 1, posted 30 Nov, 2021 ER - TY - INPR A1 - Rück, Thomas A1 - Müller, Max A1 - Jobst, Simon A1 - Weigl, Stefan A1 - Pangerl, Jonas A1 - Bierl, Rudolf A1 - Matysik, Frank-Michael T1 - Digital Twin of a Photoacoustic Trace Gas Sensor for Monitoring Methane in Complex Gas Compositions N2 - 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. Y1 - 2022 U6 - https://doi.org/10.2139/ssrn.4215170 PB - Elsevier / SSRN ER - TY - INPR A1 - Müller, Max A1 - Weigl, Stefan A1 - Müller-Williams, Jennifer A1 - Lindauer, Matthias A1 - Rück, Thomas A1 - Jobst, Simon A1 - Bierl, Rudolf A1 - Matysik, Frank-Michael T1 - Ambient methane monitoring at Hohenpeißenberg utilizing photoacoustic spectroscopy and cavity ring down spectroscopy N2 - With an atmospheric concentration of approximately 2000 parts per billion (ppbV, 10−9) methane (CH4) is the second most abundant greenhouse gas (GHG) in the atmosphere after carbon dioxide (CO2). The task of long-term and spatially resolved GHG monitoring to verify whether climate policy actions are effective, is becoming more crucial as climate change progresses. In this paper we report the CH4 concentration readings of our photoacoustic (PA) sensor over a five day period at Hohenpeißenberg, Germany. As a reference device a calibrated cavity ringdown spectrometer Picarro G2301 from the meteorological observatory was employed. Trace gas measurements with photoacoustic instruments promise to provide low detection limits at comparably low costs. However, PA devices are often susceptible to cross-sensitivities related to environmental influences. The obtained results show that relaxation effects due to fluctuating environmental conditions, e.g. ambient humidity, are a non-negligible factor in PA sensor systems. Applying algorithm compensation techniques, which are capable of calculating the influence of relaxational effects on the photoacoustic signal, increase the accuracy of the photoacoustic sensor significantly. With an average relative deviation of 1.11 % from the G2301, the photoacoustic sensor shows good agreement with the reference instrument. Y1 - 2023 U6 - https://doi.org/10.5194/egusphere-2023-1010 ER - TY - INPR A1 - Schwarz, Tobias A1 - Pastötter, Angelina A1 - Tran, Trung A1 - Schlosser, Marc A1 - Kaulen, Corinna A1 - Lechner, Alfred A1 - Kammler, Martin A1 - Slabon, Adam T1 - Effect of Temperature on the Growth of Cu(I)O Nanocubes: The Impact of the Copper Precursor Species T2 - SSRN N2 - Cuprous oxide (Cu2O) nanoparticles were synthesized using a wet chemical surfactant free method at different synthesis temperatures from 25 ◦C to 60 ◦C. Morphology, size, and chemical composition of the prepared Cu2O nanoparticles were analyzed by SEM, PXRD, and ATR-IR. We discovered that the chemical composition of the Cu2O nanoparticles remained unaffected by the synthesis temperature. However, morphology and size of the nanoparticles showed a strong temperature dependency. This could be attributed to the temperature induced formation of cupric oxide (CuO) species from the copper hydroxide (Cu(OH)2 ) precursor which also functions as copper precursor for the Cu2O nanoparticle growth. The cupric oxide species was determined to be the main cause for the formation of micrometer sized particles, whereas with the Cu(OH)2 precursor species for the Cu2O nanoparticles nanocubes with smaller edge lengths as well as octahedrons were obtained. KW - nanoparticle KW - Copper oxide KW - crystal growth KW - Crystal structure Y1 - 2024 U6 - https://doi.org/10.2139/ssrn.4909639 PB - Elsevier ER - TY - INPR A1 - Steffens, Oliver T1 - Binomial Distribution Nomogram after Larson N2 - Following an idea of Larson (1966) we construct a nomogram for cumulative binomial distribution that can be used to perform hypothesis testing, quality management (e.g. test design) and other statistical tasks. The nomogram can be printed and directly used with a simple ruler to read the results. It is instructive and as an analog computing device continuous changes are easily visible. Y1 - 2024 UR - https://www.researchgate.net/publication/383270775_Binomial_Distribution_Nomogram_after_Larson ER - TY - INPR A1 - Pangerl, Jonas A1 - Sukul, Pritam A1 - Rück, Thomas A1 - Escher, Lukas A1 - Miekisch, Wolfram A1 - Bierl, Rudolf A1 - Matysik, Frank-Michael T1 - Photoacoustic Trace-Analysis of Breath Isoprene and Acetone Via Interband- and Quantum Cascade Lasers N2 - This research presents two laser-based photoacoustic approaches for analyzing exhaled breath isoprene and acetone. The integration of a PTR-ToF-MS as a reference device ensured the reliability and accuracy of the PAS systems that is based on an ICL for isoprene and a QCL for acetone detection. The calibration yielded limits of detection of 26.9 ppbV and 1.7 ppbV, respectively, and corresponding normalized noise equivalent absorption coefficients (NNEAs) of 5.0E-9 Wcm-1Hz-0.5 and 4.9E-9 Wcm-1Hz-0.5. Laboratory as well as real breath sample measurements from alveolar breath revealed a robust system performance, with only one outlier within the static isoprene measurements. However, discrepancies emerged under dynamic breath sampling conditions, emphasizing the need for further optimization. Especially by knowing the dynamic nature and endogenous origin of exhaled isoprene our findings highlight the potential of breath analysis for non-invasive physio-metabolic and pathophysiological monitoring towards point-of-care devices. KW - photoacoustic spectroscopy KW - breath analysis/profiling KW - real-time mass spectroscopy KW - isoprene KW - acetone Y1 - 2024 U6 - https://doi.org/10.2139/ssrn.4834735 PB - Elsevier / SSRN ER - TY - INPR A1 - Tringides, Michael C. A1 - Conrad, E. H. A1 - Menzel, Andreas A1 - Voss, Neil R. A1 - Kammler, Martin A1 - Horn-von Hoegen, Michael T1 - Dynamics of atomic steps on Si(001) studied by temporal LEED spectroscopy [Poster] N2 - While surface kinetics measurements for single atom diffusion have proliferated, little work exists attempting to measure surface dynamics under equilibrium conditions. We will present our recent work on developing Temporal LEED Spectroscopy (TLS) as a dynamic probe of surfaces capable of kinetics measurements at both high temperatures and surface coverages. By tuning the diffraction to specific structural entities such as steps, islands, etc., and monitoring the diffracted signal as a function of time, dynamics information about these structures can be obtained. As an example we will present TLS results for the dynamics of step fluctuations on Si(001) [1]. We have measured activation energies and identified step-edge diffusion as the rate limiting process for 950K < T < 1130K. Although this result is in apparent disagreement with earlier work, a careful analysis, considering crossover temperatures between different microscopic processes, can reconcile the differences. 1. M. Kammler, et al., Phys. Rev. B (in press). Y1 - 2002 UR - https://www.researchgate.net/publication/252546721_Dynamics_of_atomic_steps_on_Si001_studied_by_temporal_LEED_spectroscopy_poster ER - TY - INPR A1 - Pangerl, Jonas A1 - Moser, Elisabeth A1 - Müller, Max A1 - Weigl, Stefan A1 - Jobst, Simon A1 - Rück, Thomas A1 - Bierl, Rudolf A1 - Matysik, Frank-Michael T1 - A Highly Sensitive Acetone and Ethanol Quantum Cascade Laser Based Photoacoustic Sensor: Characterization and Multi-Component Spectra Recording in Synthetic Breath T2 - SSRN Electronic Journal N2 - Trace gas analysis in breath is challenging due to the vast number of different components. We present a highly sensitive quantum cascade laser based photoacoustic setup for breath analysis. Scanning the range between 8260 and 8270 nm with a spectral resolution of 48 pm, we are able to quantify acetone and ethanol within a typical breath matrix containing water and CO2. We photoacoustically acquired spectra within this region of mid-infra-red light and prove that those spectra do not suffer from non-spectral interferences. The purely additive behavior of a breath sample spectrum was verified by comparing it with the independently acquired single component spectra using Pearson and Spearman correlation coefficients. A previously presented simulation approach is improved and an error attribution study is presented. With a 3σ detection limit of 6.5 ppbV in terms of ethanol and 250 pptV regarding acetone, our system is among the best performing presented so far. KW - Photoacoustic spectroscopy KW - quantum cascade laser KW - spectral simulation KW - breath analysis KW - acetone Y1 - 2022 U6 - https://doi.org/10.2139/ssrn.4305376 PB - Elsevier ER - TY - INPR A1 - Fischer, Johannes A1 - Hirsch, Thomas A1 - Reitmeier, Torsten A1 - Bierl, Rudolf T1 - Real-time hardware-based processing of high-precision detector signals for surface plasmon resonance spectroscopy N2 - Surface plasmon resonance (SPR) is limited by small-signal detectability and drift when subtraction occurs in software after digitization. We introduce an SPR detector that performs on-detector amplification and analog differential readout, eliminating moving parts and software-heavy correction. The hardware-native subtraction boosts the usable ADC range and suppresses illumination and environmental noise. In fixed-angle refractive-index steps (NaCl), the platform resolves Δn_min ≈ 1.8 × 10⁻⁷ RIU compared to 4.6–7.2 × 10⁻⁶ RIU on a commercial comparator and improves small-signal SNR by up to ∼5,000-fold, while remaining competitive at high signal levels. In a model IgG–BSA assay, the detector’s low noise floor clarifies early binding and equilibrium transitions. By generating inherently clean raw signals, this hardware-native approach dramatically enhances sensitivity and long-term stability for label-free biosensing and inline process analytics while rendering AI-based or complex post-processing entirely unnecessary. The concept generalizes across platforms and opens a compact route to robust, high-fidelity SPR in complex environments, with a clear path toward multi-wavelength and arrayed detectors for high-throughput chemical monitoring. KW - Drift-free SPR KW - Hardware-native sensing KW - Noise suppression KW - On-detector amplification KW - Small-signal detection KW - Surface plasmon resonance Y1 - 2025 U6 - https://doi.org/10.2139/ssrn.5971170 ER -