70 research outputs found

    Impact of Soiling on Transparency of Different Glass Types: A Comparative Study

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    To improve the optical properties of photovoltaic (PV) modules, many manufacturers use new glass surface structures that reduce glare. However, these modifications can increase susceptibility to soiling. This research presents a new method for assessing soiling by positioning glasses without solar cells on a reference PV module. With this method, the soiling of the glasses can be measured without the systematic measurement uncertainties from the power or irradiance measurement negatively affecting the measurement accuracy. To demonstrate the method, five glass types are tested at four tilt angles at three locations. In this paper, the preliminary results are presented together with the soiling data after two months at a selected site

    Selecting Key Features of 3D Object Model for Relative Pose Estimation

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    This paper addresses the discussion of the complexity and level of detail of the 3D model of a target satellite that is required in order to get a stable and accurate relative pose estimation with monocular cameras during an On-Orbit Servicing (OOS) mission scenario. We assume to know the target 3D mesh with thousands of vertices before the mission takes place. Nevertheless, for on-board pose estimation we have to use compact 3D models of the targets with only some key points. In this paper we compare the pose estimation results using three models for tests. The first model has manually extracted key features, where the second one includes only features extracted with Harris3D technique. The third model includes a part of Harris3D key features and some manually selected points. The offline pose estimation tests were using the data from European Proximity Operations Simulator (EPOS) facility

    Robust feature extraction pose estimation during fly-around and straight-line approach in close range.

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    This paper refers to the field of visual navigation in OnOrbit Servicing (OOS) and/or Active Debris Removal (ADR) missions. Mainly the robust feature extraction pose estimation technique is proposed here to estimate target while approaching it. This method is tested with two image datasets from different sensors in open loop. The stable tracking during the fly-around and straight line approach gives a positive feedback to consider this technique as a possible candidate for the future missions

    A robust navigation filter fusing delayed measurements from multiple sensors and its application to spacecraft rendezvous

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    A filter is an essential part of many control systems. For example guidance, navigation and control systems for spacecraft rendezvous require a robust navigation filter that generates estimates of the state in a smooth and stable way. This is important for a safe spacecraft navigation within rendezvous missions. Delayed, asynchronous measurements from possibly different sensors require a new filter technique which can handle these different challenges. A new method is developed which is based on an Extended Kalman Filter with several adaptations in the prediction and correction step. Two key aspects are extrapolation of delayed measurements and sensor fusion in the filter correction. The new filter technique is applied on different close-range rendezvous examples and tested at the hardware-in-the-loop facility EPOS 2.0 (European Proximity Operations Simulator) with two different rendezvous sensors. Even with realistic delays by using an ARM-based on-board computer in the hardware-in-the-loop tests the filter is able to provide accurate, stable and smooth state estimates in all test scenarios

    10-Year Anniversary of the European Proximity Operations Simulator 2.0 - Looking Back at Test Campaigns, Rendezvous Research and Facility Improvements

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    Completed in 2009, the European Proximity Operations Simulator 2.0 (EPOS 2.0) succeeded EPOS 1.0 at the German Space Operations Center (GSOC). One of the many contributions the old EPOS 1.0 facility made to spaceflight rendezvous is the verification of the Jena-Optronik laser-based sensors used by the Automated Transfer Vehicle. While EPOS 2.0 builds upon its heritage, it is a completely new design aiming at considerably more complex rendezvous scenarios. During the last ten years, GSOC’s On-Orbit-Servicing and Autonomy group, who operates, maintains and evolves EPOS 2.0, has made numerous contributions to the field of uncooperative rendezvous, using EPOS as its primary tool. After general research in optical navigation in the early 2010s, the OOS group took a leading role in the DLR project On-Orbit-Servicing End-to-End Simulation in 2014. EPOS 2.0 served as the hardware in the loop simulator of the rendezvous phase and contributed substantially to the project’s remarkable success. Over the years, E2E has revealed demanding requirements, leading to numerous facility improvements and extensions. In addition to the OOS group’s research work, numerous and diverse open-loop test campaigns for industry and internal (DLR) customers have shaped the capabilities of EPOS 2.0 significantly

    Patient satisfaction with divided anesthesia care.

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    BACKGROUND Up to now, no prospective cohort study using a validated questionnaire has assessed patients' expectation and perception of divided anesthesia care and its influence on patient satisfaction. OBJECTIVE We assessed patient satisfaction with divided anesthesia care in a district general hospital in Switzerland. We hypothesized that patient expectations, combined with their perceptions of the (un)importance of continuous anesthesia care would influence patient satisfaction. MATERIAL AND METHODS A total of 484 eligible in-patients receiving anesthesia from October 2019 to February 2020 were included and received preoperative information about divided care via a brochure and face-to-face. The primary outcome was the assessment of patient satisfaction with divided anesthesia care using a validated questionnaire. In group 1 continuity of care was considered important but not performed. In group 2 continuity was ensured. In group 3 continuity was regarded as not important and was not performed. In group 4 patients could not remember or did not answer. A psychometrically developed validated questionnaire was sent to patients at home after discharge. RESULTS A total of 484 completed questionnaires (response rate 81%) were analyzed. In group 1 (n = 110) the mean total dissatisfaction score was 25% (95% confidence interval [CI] 21.8-28.1), in group 2 (n = 61) 6.8% (95% CI 4.8-8.7), in group 3 (n = 223) 12.1% (95% CI 10.7-13.4), and in group 4 (n = 90) 15% (95% CI 11-18); ANOVA: p < 0.001, η = 0.43. Of the patients 286 (59%) considered continuity of care by the same anesthetist relatively unimportant (34%) or not important at all (25%). The other 40% considered it important (22%) or very important (18%). CONCLUSION Despite receiving comprehensive preoperative information about divided anesthesia care, 40% of patients still considered continuity of care by the same anesthetist important. We recommend further research evaluating whether and how patient expectations can be modified towards the common practice of divided care and patient satisfaction can be increased

    Creation of a method for the adoption of digital transformation for medium enterprises in the education business in Switzerland

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    The education sector, like most others, is currently experiencing a rapidly advancing digital transformation. Due to the current COVID-19 pandemic, this process is taking place faster than it would have without the virus. Currently, there are no methods that allow the affected educational institutions to quickly and efficiently implement the digital transformation. As a first step of this work, online research was conducted to determine the current state of digital transformation in the education sector in relation to the elaborated requirements. To identify differences between educational institutions of different sizes and to reach a specific analysis of the domain, the educational institutions were divided into different categories according to the number of their employees. A survey was then prepared and sent to all identified educational institutions for processing. The main goal of the survey was to reflect the current state of the educational institutions. Furthermore, the requirements as well as the efforts of the individual institutions in the area of digital transformation were of high interest. As a second step, based on the analysis of the survey, a method was created to support the educational institutions in the digital transformation, taking into account their current situation and their progress and status of digital transformation. For further research, a more detailed investigation of how the method works in practice could be conducted

    Therapeutic alliance, social inclusion and infection control - Towards pandemic-adapted mental health care services in Switzerland

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    The Covid-19 pandemic has challenged the Swiss mental health care system. Many services were downsized or closed and admission to treatment and care institutions was restricted during lockdown. While these measures were necessary according to the general containment and mitigation strategies of federal and cantonal authorities, this situation has had negative consequences for care and treatment of service users. This paper asks to re-think key aspects of the Swiss mental health care system that have demonstrated to be not adaptable to the pandemic. In particular, the paper suggests diversifying care and treatment settings and strengthening outpatient and outreach services. Finally, some proposals to foster social inclusion during and after the pandemic are outline

    Key Contributions by the Swiss Tropical and Public Health Institute Towards New and Better Drugs for Tropical Diseases

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    Thanks to its expertise in clinical research, epidemiology, infectious diseases, microbiology, parasitology, public health, translational research and tropical medicine, coupled with deeply rooted partnerships with institutions in low- and middle-income countries (LMICs), the Swiss Tropical and Public Health Institute (Swiss TPH) has been a key contributor in many drug research and development consortia involving academia, pharma and product development partnerships. Our know-how of the maintenance of parasites and their life-cycles in the laboratory, plus our strong ties to research centres and disease control programme managers in LMICs with access to field sites and laboratories, have enabled systems for drug efficacy testing in vitro and in vivo, clinical research, and modelling to support the experimental approaches. Thus, Swiss TPH has made fundamental contributions towards the development of new drugs – and the better use of old drugs – for neglected tropical diseases and infectious diseases of poverty, such as Buruli ulcer, Chagas disease, food-borne trematodiasis (e.g. clonorchiasis, fascioliasis and opisthorchiasis), human African trypanosomiasis, leishmaniasis, malaria, schistosomiasis, soil-transmitted helminthiasis and tuberculosis. In this article, we show case the success stories of molecules to which Swiss TPH has made a substantial contribution regarding their use as anti-infective compounds with the ultimate aim to improve people’s health and well-being

    The Vampire Study: Significant elevation of faecal calprotectin in healthy volunteers after 300 ml blood ingestion mimicking upper gastrointestinal bleeding

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    Background Faecal calprotectin correlates with histological and clinical activity in inflammatory bowel disease. Gastrointestinal bleeding might also increase faecal calprotectin levels, erroneously implying intestinal inflammation; however, this possibility has not been systematically assessed. Methods Sixteen healthy volunteers without gastrointestinal disease and normal faecal calprotectin baseline values ingested their own blood twice, either by drinking or via nasogastric tube. Quantities of 100 ml and 300 ml blood were ingested in a randomised order, with a 28-day wash-out period. Faecal calprotectin, faecal occult blood test, and the occurrence of melaena were assessed. Faecal calprotectin ≥ 50 µg/g was considered elevated. Results Melaena was reported by all healthy volunteers after 300 ml and by 11/15 healthy volunteers (71%) after 100 ml blood ingestion. One day after ingestion of 300 ml blood, 8/16 faecal calprotectin tests were positive compared to 1/16 at baseline ( = 0.016). Faecal calprotectin levels above > 200 µg/g were rarely observed. There was a trend for faecal calprotectin test positivity also after ingestion of 100 ml. Conclusion Ingestion of blood resulted in an increase in faecal calprotectin-positive tests. Gastrointestinal bleeding should be considered as a potential cause of mild faecal calprotectin elevation > 50 µg/g; however, increased faecal calprotectin above > 250-300 µg/g, the established cut-off for relevant intestinal inflammation in patients with inflammatory bowel disease, is rare
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