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Silver halide polycrystalline infrared fibers (PIR) have unique properties such as excellent transmittance in the spectral range from 3 to 17 µm, while also being highly flexible, non-toxic, and non-hygroscopic. They are used in industry and medicine for CO2-laser power delivery, flexible infrared imaging, and remote process spectroscopy. While PIR fibers possess a quite low attenuation (0.1-0.5 dB/m) in the 8-12 µm range, their total transmittance is limited by significant Fresnel reflections at the fiber end faces due to the high refractive index of silver halide (>2.1). Functionalization of these surfaces with specially designed Anti-Reflective Microstructures (ARMs) enables a striking enhancement of fiber transmittance. In this work, direct imprinting (or embossing) of microstructures to fiber ends and their profiling with a microstructured knife was applied to fabricate such ARMs. The resulting two-dimensional Moth-eye microstructures and one-dimensional microgrooves at the PIR-fiber ends enable to an increase of fiber transmittance in a broadband range of (5-17 µm) as well as to reach up to 20% improvement for PIR-fiber laser cables used for power delivery of CO2-lasers at 10.6 µm.
Progress in the diagnosis of leishmaniases depends on the development of effective methods and the discovery of suitable biomarkers. We propose firstly an update classification of Leishmania species and their synonymies. We demonstrate a global map highlighting the geography of known endemic Leishmania species pathogenic to humans. We summarize a complete list of techniques currently in use and discuss their advantages and limitations. The available data highlights the benefits of molecular markers in terms of their sensitivity and specificity to quantify variation from the subgeneric level to species complexes, (sub) species within complexes, and individual populations and infection foci. Each DNA-based detection method is supplied with a comprehensive description of markers and primers and proposal for a classification based on the role of each target and primer in the detection, identification and quantification of leishmaniasis infection. We outline a genome-wide map of genes informative for diagnosis that have been used for Leishmania genotyping. Furthermore, we propose a classification method based on the suitability of well-studied molecular markers for typing the 21 known Leishmania species pathogenic to humans. This can be applied to newly discovered species and to hybrid strains originating from inter-species crosses. Developing more effective and sensitive diagnostic methods and biomarkers is vital for enhancing Leishmania infection control programs.
The share of chronic odontogenic rhinosinusitis is 40% among all chronic rhinosinusitis. Using automated information systems for differential diagnosis will improve the efficiency of decision-making by doctors in diagnosing chronic odontogenic rhinosinusitis. Therefore, this study aimed to develop an intelligent decision support system for the differential diagnosis of chronic odontogenic rhinosinusitis based on computer vision methods. A dataset was collected and processed, including 162 MSCT images. A deep learning model for image segmentation was developed. A 23 convolutional layer U-Net network architecture has been used for the segmentation of multi-spiral computed tomography (MSCT) data with odontogenic maxillary sinusitis. The proposed model is implemented in such a way that each pair of repeated 3 × 3 convolutions layers is followed by an Exponential Linear Unit instead of a Rectified Linear Unit as an activation function. The model showed an accuracy of 90.09%. To develop a decision support system, an intelligent chatbot allows the user to conduct an automated patient survey and collect patient examination data from several doctors of various profiles. The intelligent information system proposed in this study made it possible to combine an image processing model with a patient interview and examination data, improving physician decision-making efficiency in the differential diagnosis of Chronic Odontogenic Rhinosinusitis. The proposed solution is the first comprehensive solution in this area.
The aim of our study was to investigate the impact of insulin resistance on the bone density of the upper wall of the maxillary sinus. Materials and Methods: The study included 100 female participants aged 18 to 44 years, divided into two groups. The first group consisted of individuals with insulin resistance, while the control group comprised individuals without signs of insulin resistance. In each group, we conducted an investigation of the radiological density of the upper wall of the maxillary sinus using uncertainty calculations. Results of the study suggest a potential influence of insulin resistance on the density of bone tissue around the nasal sinuses, specifically the upper wall of the maxillary sinus in our case. This parameter was found to be minimal in the group of individuals with insulin resistance. It is particularly noteworthy that both minimum and maximum bone density decreased in this group. Conclusions. The research focused on how insulin resistance affects the density of the upper wall of the maxillary sinus. By employing uncertainty calculations, the study revealed that insulin resistance is associated with a decrease in the minimum density of the upper wall of the maxillary sinus. This tendency may act as a catalyst for the emergence of significant inflammatory alterations in the nasal sinuses, serving as a foundation for the initiation of complications.
Cutaneous leishmaniasis (CL) is a skin infection caused by a single-celled parasite that is transmitted by the bite of a phlebotomine sandfly. CL is the most common form of leishmaniasis characterized by localized lesions in the skin and mucous membranes. The disease is prevalent in all countries around the Mediterranean Basin. In this paper, we describe spatiotemporal and eco-epidemiological parameters of CL in Libya. Moreover, we explored current spatiotemporal distributions of CL cases and explored the future projection of the disease. Our study indicates the presence of higher risk of CL in the coastal regions of Libya. Future projection until 2060 showed a trend of increasing incidence of CL in the north-western part of Libya, a spread along the coastal region and a possible emergence of new endemics in the north-eastern districts of Libya. These scenarios should be considered by health authorities in order to develop appropriate intervention strategies and plan effective control programs.
Background
Cutaneous leishmaniasis (CL) is a vector-borne parasitic diseases of public health importance that is prevalent in the West Bank but not in the Gaza Strip. The disease caused by parasitic protozoans from the genus Leishmania and it is transmitted by infected phlebotomine sand flies. The aim of our study is to investigate the eco-epidemiological parameters and spatiotemporal projections of CL in Palestine over a 30-years period from 1990 through 2020 and to explore future projections until 2060.
Methodology/Principal findings
This long-term descriptive epidemiological study includes investigation of demographic characteristics of reported patients by the Palestinian Ministry of Health (PMoH). Moreover, we explored spatiotemporal distribution of CL including future projection based on climate change scenarios. The number of CL patients reported during this period was 5855 cases, and the average annual incidence rate (AAIR) was 18.5 cases/105 population. The male to female ratio was 1.25:1. Patients-age ranged from 2 months to 89 years (mean = 22.5, std 18.67, and the median was 18 years). More than 65% of the cases came from three governates in the West Bank; Jenin 29% (1617 cases), Jericho 25% (1403), and Tubas 12% (658) with no cases reported in the Gaza Strip. Seasonal occurrence of CL starts to increase in December and peaked during March and April of the following year. Current distribution of CL indicate that Jericho, Tubas, Jenin and Nablus have the most suitable climatic settings for the sandfly vectors. Future projections until 2060 suggest an increasing incidence from northwest of Jenin down to the southwest of Ramallah, disappearance of the foci in Jericho and Tubas throughout the Jordan Vally, and possible emergence of new foci in Gaza Strip.
Conclusions/Significance
The future projection of CL in Palestine until 2060 show a tendency of increasing incidence in the north western parts of the West Bank, disappearance from Jericho and Tubas throughout the Jordan Vally, and emergence of new CL endemic foci in the Gaza Strip. These results should be considered to implement effective control and surveillance systems to counteract spatial expansion of CL vectors.
Dislocation free local SiGe-on-insulator (SGOI) virtual substrate is fabricated using lateral selective SiGe growth by reduced pressure chemical vapor deposition. The lateral selective SiGe growth is performed around a ∼1.25 μm square Si (001) pillar in a cavity formed by HCl vapor phase etching of Si at 850 °C from side of SiO2/Si mesa structure on buried oxide. Smooth root mean square roughness of SiGe surface of 0.14 nm, which is determined by interface roughness between the sacrificially etched Si and the SiO2 cap, is obtained. Uniform Ge content of ∼40% in the laterally grown SiGe is observed. In the Si pillar, tensile strain of ∼0.65% is found which could be due to thermal expansion difference between SiO2 and Si. In the SiGe, tensile strain of ∼1.4% along 〈010〉 direction, which is higher compared to that along 〈110〉 direction, is observed. The tensile strain is induced from both [110] and [−110] directions. Threading dislocations in the SiGe are located only ∼400 nm from Si pillar and stacking faults are running towards 〈110〉 directions, resulting in the formation of a wide dislocation-free area in SiGe along 〈010〉 due to horizontal aspect ratio trapping.
Micro-Transfer printing (µTP) is a promising technique for hetero-integration of III-V materials into Si-based photonic platforms. To enhance the print yield by increasing the adhesion between the III-V material and Si or SiO2 surface, an adhesion promoter like Benzocyclobutene is typically used as interlayer. In this work, we demonstrate µTP of InP based coupons on SiO2 interlayer without any adhesive interlayer and investigate the mechanism of adhesive free bonding. Source coupons are InP-based coupon stacks on a sacrificial layer that is removed by a chemical wet etch with FeCl3. For the target we fabricated amorphous-Si waveguides on 8” wafer encapsulated by a High Density Plasma SiO2 which was planarized by a chemical mechanical polishing procedure. We used O2 plasma to activate both source and target to increase adhesion between coupon and substrate. To get a better understanding of the bonding mechanism we applied several surface characterization methods. Root mean square roughness of InP and SiO2 was measured by atomic force microscopy before and after plasma activation. The step height of the micro-transfer printed source coupon on the target wafer is estimated by optical step profiler. We used Raman peak position mappings of InP to analyze possible strain and contact angle measurements on SiO2, before and after plasma activation to observe a change in the hydrophilicity of the surface. X-ray Photoelectron Spectroscopy analysis was used to characterize the surface energy states of P2p, In3d, O1s for InP source and Si2p, O1s for SiO2 target. Our results demonstrate direct bonding of InP coupons by means of µTP without the need of a strain-compensation layer. In this way, a promising route towards Complementary Metal-Oxide-Semiconductor compatible use of µTP for the hetero-integration of InP is provided.
Individualisierbare, webbasierte Benutzerschnittstelle zur Überwachung von Industrieprozessen
(2023)
Im Rahmen eines Projektes zur Applikation der Präskriptiven Analytik für die dynamische Prozessführung von intelligenten Kälteanlagen wurde eine webbasierte Software mit einer anwenderfreundlichen und individualisierbaren Benutzerschnittstelle zur Überwachung und Regelung umgesetzt. Als Teilprojekt wurde ein Softwarepaket entwickelt, welches eine konfigurierbare Anlagenvisualisierung für diese Benutzerschnittstelle umsetzt. Beim Entwurf und der Implementierung der Software wurde auf einen modularen Aufbau geachtet, sodass die Software leicht erweiterbar und aus auswechselbaren, unabhängigen Komponenten zusammengesetzt ist.
Single Pilot Operations is a current topic with the potential to significantly affect the future of commercial aviation. While financially attractive for airlines, Single Pilot Operations bring forth important safety concerns, especially regarding the lack of human redundancy in the flight deck, an increased workload for the single pilot, reduced situational awareness and a higher risk of human error.
It is assumed that potential problems affecting Single Pilot Operations could be addressed by implementing an Augmented Reality (AR) device in the flight deck, by presenting additional information and supporting hints within the pilot’s field of view. Concretely, AR could be used to help reduce the single pilot’s workload, improve situational awareness and reduce the risk of human error.
This paper sets out to demonstrate two use cases for augmented reality in the flight deck. A system, called Pilot Assist, was developed that allows pilots to conduct checklists interactively with a Microsoft HoloLens. The system also provides a holographic Head-up-Display. Pilot Assist was developed and demonstrated with a fixed base Airbus A320 simulator at the Technical University of Wildau.
With the HoloLens’ spatial mapping capabilities – scanning and recognizing the environment around the user – it was possible to create a system that guides the pilot through the conduction of checklists. This is done by prompting the user towards the location of each checklist item in the cockpit, where information regarding necessary actions is projected. Furthermore, Pilot Assist is integrated with the aircraft systems, making it possible to obtain aircraft status data in real time, thus allowing error-checking of the pilot’s actions as well as automating the progress through checklists.
The holographic Head-up-Display allows the user to look at the surrounding environment while presenting critical flight data within the user’s field of view. The holographic Head-up-Display is intended to contribute to the pilot’s situational awareness.
Experts in the aviation field, including pilots, researchers and engineers had the chance to qualitatively assess the Pilot Assist tool. They pointed to limitations of both Pilot Assist and the HoloLens itself, but shared optimism as to how this technology and similar applications could indeed impact the future of flight operations. Concerns regarding the HoloLens’ weight, comfort and narrow field of view were expressed. However, continued development of head mounted devices (e.g. HoloLens 2) is expected in the coming years.
Further research into augmented reality applications in the flight deck is needed to advance this and other use cases. Nonetheless, the experts agreed Pilot Assist provides beneficial support during single pilot operation considering the current prototypical nature of the system.
Es wird ein neuer Ansatz zur Verkehrs- und Kostenreduzierung im Wirtschaftsverkehr (genauer Lieferverkehr) untersucht. Die virtuelle Zusammenfassung von Bestellungen z.B. über eine Internet-/Intranetplattform - eine Empfänger/Bestellerkooperation kann möglicherweise zur Bündelung der Lieferverkehre führen. Aufgrund von neuen Produktionsmethoden und Managementstrategien zur Stärkung der Eigenverantwortlichkeit von Unternehmensbereichen und Abteilungen laufen Bestellprozesse oft separat und unkoordiniert ab. Eine Folge ist die Zersplitterung der Bestellungen und die geringe Auslastung von Lieferverkehren. Neben dieser Dezentralisierung führt „Outsourcen“ dazu, dass Bestellungen immer kleinteiliger und weniger zusammengefasst werden. Um trotzdem Kosten zu sparen versuchen Lieferanten Bündelungen durchzuführen. Dies geschieht bei Spedition am ehesten unternehmensintern aber auch in Netzwerken oder bei der City-Logistik auch überbetrieblich als Versenderkooperation. Dies ist aber nur die eine Seite des Beschaffungsprozesses. Außerdem ist der Versenderkooperation durch Konkurrenzsituationen Grenzen gesetzt. Auf der anderen Seite ist eine Bündelung (der Bestellungen) ebenfalls denkbar, wenn sich daraus Vorteile für die Besteller ergeben, z.B. Preisreduktionen aufgrund größerer Bestellmengen. Das wäre eine Besteller- bzw. Empfängerkooperation. Die Besteller/Empfänger schließen sich zusammen und nehmen durch die Bestellungsbündelung den Versendern und Transporteuren quasi die Abstimmungs-Probleme einer Kooperation untereinander teilweise ab. Werden Lieferprozesse mit in die Kooperation integriert, handelt es sich um eine Beschaffungs-kooperation. Früher war eine solche Bündelung auf Bestellerseite durch große bestellende Einheiten (Werksgröße, Zentralisierung, hohe Produktionstiefe,...) per se gegeben. Diese Produktions-methoden sind nicht einfach wieder herstellbar. Eine virtuelle Bündelung z.B. mittels E Procurement (u.a. Internet-Bestellplattform) wäre heute zeitgemäß. Diese realisiert quasi eine virtuelle Zentralbestellung innerbetrieblich für dezentral organisierte Strukturen oder überbetrieblich zwischen unabhängigen Unternehmen. Die hauptsächlichen Vorteile einer solchen Kooperation sind neben Prozessvereinfachung, Transparenzerhöhung sowie Verbesserung der Steuerung und Kontrolle bei der Beschaffung, Kosteneinsparung durch Aufwandsminimierung und Nutzung von Preisrabatten durch Bündelung der Bestellmengen von mehreren Bestellern. Im Wirtschaftsverkehr sind Effizienzsteigerung und Verkehrsreduzierung durch Kooperationen noch wenig untersucht. Insbesondere Planungsinstrumente zur Förderung solcher Kooperationen müssen entwickelt werden. Innerhalb dieser Arbeit fanden umfangreiche Erhebungen statt. In Felduntersuchungen an der Technische Universität Berlin, verschiedenen Gewerbegebieten, Handelseinrichtungen (Shop-in-Shop-Systemen) und Bürohäusern wurden Beschaffungsprozesse, Organisationsprobleme und Kooperationsneigungen analysiert. Auf Grundlage der Erkenntnisse aus diesen quantitativen Befragungen und zusätzlichen qualitativen Experteninterviews zur Beschaffung sind verschiedene Varianten des Ansatzes entwickelt worden. In einer abschließenden deutschlandweiten Online-Unternehmensbefragung mit 1.700 auswertbaren Antworten, einer Conjoint-Analyse und weiteren Experteninterviews wurden verkehrliche Wirkungen untersucht, Kooperationsansätze bewertet und weiter entwickelt.
V2V communication enables a plethora of cooperative applications aimed at reducing road hazard situations as well as enhancing traffic efficiency and individual driving comfort, expanding therewith the boundaries of Advanced Driver Assistance Systems (ADAS). These applications will be supported by IEEE 802.11p, a standard operating in the 5.9 GHz frequency band and adapted for the highly dynamic vehicular environment.
The focus of this work is V2V safety applications, which have already gained a major attention from the industry, academia, as well as standardization bodies. Being a subject of wireless communication the performance of V2V applications directly depends on the communication link quality and the packet distribution pattern. Therefore, the main purpose of this thesis is to develop an effective communication link reliability assessment method and analyze to what extent V2V communication is feasible to satisfy the reliability requirements of safety applications. Furthermore, we investigate the effectiveness of the proposed assessment method when applied for real-time communication link reliability prediction.
In particular, in this work we establish the link between classical network performance metrics and specific application reliability requirements and derive a set of advanced assessment metrics. Afterwards, we investigate through these metrics how different environmental factors affect application reliability based on the measurement data, which was obtained in elaborated real-world measurement campaigns and in different non-line-of-sight scenarios. Using the suggested metrics further in this work
we additionally analyze the achievable application reliability of the V2V safety applications in congested network scenarios through the simulation study. Based on these results we also define the most favorable combinations of the network parameters to support reliable operation of these applications.
Finally, in this thesis we examine to what extent the suggested metrics are suitable for applications while operating in real time. We develop and implement two frameworks for prediction of the communication link reliability, based on the data that was obtained over the 4.5 months of the simTD project field trials. Furthermore, we apply both frameworks to other measurement data, which was obtained outside the simTD project and assess the effectiveness of both frameworks under independent realistic
conditions.
Mit diesem Beitrag soll der Einsatz von iBeacons als Basis eines Indoor-Ortungssystems in der Hochschulbibliothek der Technischen Hochschule Wildau vorgestellt werden. Für die Ortung innerhalb von Gebäuden sind bisher unterschiedliche Strategien zum Einsatz gekommen. Die von Apple Inc. entwickelte iBeacon-Technologie kommuniziert über Bluetooth Low Energy (BLE) und setzt somit eine Technologie ein, die einen großen Kreis von Nutzern erreicht. Als wesentlicher Teil der Campus-App Unidos Wildau operiert das Ortungssystem auf der Basis des Kartendienstes iCampus Wildau Maps. Gemachte Erfahrungen mit der iBeacon-Technologie werden ebenso im Fokus dieses Beitrags stehen wie Ergebnisse der Implementierung unseres Ortungssystems sowie Pläne für die Weiterentwicklung.
Characterization and Tests of Different Mach-Zehnder Silicon Photonic Modulator Configurations
(2020)
We designed and produced an integrated silicon photonic circuit, in a single chip with IHP SG25H4_EPIC 0.25 µm technology. A Mach-Zehnder interferometer with an alternative shape for better integration, together with a standard-shape Mach-Zehnder interferometer have been realized. In this work, preliminary results of comparative performance measurements between the two Mach-Zehnder interferometer are shown.
Visceral leishmaniasis (VL), caused by the members of the Leishmania donovani complex, has been responsible for devastating VL epidemics in the Sudan. Multilocus microsatellite and sequence typing studies can provide valuable insights into the molecular epidemiology of leishmaniasis, when applied at local scales. Here we present population genetic data for a large panel of strains and clones collected in endemic Sudan between 1993 and 2001.
Knowledge of optical constants, i.e. refractive index n and extinction coefficient k, and light scattering properties of optical polymers are required to optimize micro-optics for light-emitting diodes in terms of efficiency, color properties and light distribution. We present here a model-based diagnostic approach to determine the optical properties of polymers, which should be particularly useful in the development of plastics for optical applications. Optical constants and scattering coefficients were obtained from transmission and reflection measurements in a wavelength range from UV to NIR taking into account scattering effects due to rough surfaces and volume inhomogeneity. Based on the models for the dielectric function, the molecular optical transition energies Eg, critical point energies, Urbach energies and exciton transition energies were determined. Rayleigh and Mie scattering model and van de Hulst's anomalous diffraction theory were applied to characterize scattering due to volume inhomogeneities. Scalar diffraction theory was applied to account for surface roughness scattering. Atomic force microscopy with nanomechanical characterization was used to characterize domains in size and shape and to assign optical scattering to a suitable morphological model. The combined optical and mechanical characterization help to improve the qualification of new polymer materials for optical applications.
Through Silicon Via (TSV) technology is a key in 3D integration of circuits by the creation of interconnects using vias, which go through the full silicon wafer. Typically, a highly-selective Bosch Si etch process is used. It is characterized by a high etch rate at a high aspect ratio, whereby scallops on the sidewalls are generated. In this work, square via arrays with dimensions from 3 to 50 μm and up to 300 μm depth were fabricated and analyzed by spectroscopic reflectometry. The reflectometric data are compared to simulations by a novel theoretical approach. In order to simulate the reflectance spectra of TSV arrays, a combination of 2D and 3D rigorous coupled wave analysis was applied. Besides the via depth, the sidewall angle and the corner radius of the bottom profile were considered in the model. The general requirements on spectral resolution in TSV metrology are discussed.
In this work we present a novel optical polymer system based on polyurethane elastomer components, which combines excellent UV transparency with high thermal stability, good hardness, high surface tension and long pot life. The material looks very promising for encapsulation and microlensing applications for chip-on-board (CoB) light-emitting diodes (LED). The extinction coefficient k, refractive index n, and bandgap parameters were derived from transmission and reflection measurements in a wavelength range of 200-890 nm. Thermogravimetry and differential scanning calorimetry were used to provide glass transition and degradation temperatures. The surface tension was determined by means of contact angle measurements. As proof of concept, a commercial InGaN-CoB-LED is used to demonstrate the suitability of the new material for the production of microlenses.
Through Silicon Via (TSV) technology is a key feature of new 3D integration of circuits by creation of interconnections using vias, which go through the silicon wafer. Typically, the highly-selective Bosch Si etch process, characterized by a high etch rate and high aspect ratio and forming of scallops on the sidewalls is used. As presented in this paper, we have developed an experimental setup and a respective evaluation algorithm for the control and monitoring of very high aspect ratio TSV profiles by spectroscopic reflectometry. For this purpose square via arrays with lateral dimension from 3 to 10 μm were fabricated by a Bosch etch process and analyzed by our setup. By exploiting interference and diffraction effects of waves reflected from the top and bottom surfaces as well as from the side walls of the TSV patterns, the measurements provided etch depths, CD values and scallop periods. The results were compared with data obtained by a commercial wafer metrology tool. Aspect ratios of up to 35:1 were safely evaluable by our setup.