222 research outputs found
First proof of concept of remote attendance for future observation strategies between Wettzell (Germany) and Concepción (Chile)
No full textCurrent VLBI observations are controlled and attended locally at the radio telescopes on the basis of pre-scheduled session files. Operations have to deal with system specific station commands and individual setup procedures. Neither the scheduler nor the correlator nor the data-analyst gets real-time feedback about system parameters during a session. Changes in schedules after the start of a session by remote are impossible or at least quite difficult. For future scientific approaches, a more flexible mechanism would optimize the usage of resources at the sites. Therefore shared-observation control between world-wide telescope s, remote attendance/control as well as completely unattended-observations could be useful, in addition to the classic way to run VLBI observations. To reach these goals, the Geodetic Observatory Wettzell in cooperation with the Max-Planck-Institute for Radio Astronomy (Bonn) have developed a software extension to the existing NASA Field System for remote control. It uses the principle of a remotely accessible, autonomous process cell as server extension to the Field System on the basis of Remote Procedure Calls (RPC). Based on this technology the first completely remote attended and controlled geodetic VLBI session between Wettzell, Germany and Concepción, Chile was successfully performed over 24 hours. This first test was extremely valuable for gathering information about the differences between VLBI systems and measuring the performance of internet connections and automatic connection re-establishments. During the 24h-session, the network load, the number of sent/received packages and the transfer speed were monitor ed and captured. It was a first reliable test for the future wishes to control several telescopes with one graphical user interface on different data transfer rates over large distances in an efficient way. In addition, future developments for an authentication and user role management will be realized within the upcoming NEXPReS project
Social Circle-Enhanced Fashion Recommendations System
No full textWhen shopping for fashionable clothing items, consumers frequently experience indecision and struggle to make choices, resulting in a stalling of the purchasing process. In such scenarios, most often they need support of their friends from their social circle to choose suitable clothes for different events. To provide decision-making support, considerable research has focused on generating social-aware recommendations that incorporate input from the user’s social circle. However, there has been minimal research dedicated to develop and evaluate such systems that could assess the importance of social circles in producing social-aware fashion recommendations and identifying factors that might enhance these recommendations. This paper addresses these limitations by developing a Social Circle-Enhanced Fashion Recommendation (SCEFR) System that encompasses friends feedback to generate recommendations. The SCEFR system was evaluated by conducting a user study, comparing system-generated recommendations with user choices as rank correlation coefficients. The findings indicate that inputs from the social circle alone have limited potential in generating effective social-aware recommendations. However, when the user’s shopping preferences were shared with their social circle, the quality of these recommendations significantly improved, as evidenced by a qualitative analysis of user feedback. Furthermore, in comparative analysis with the state-of-the-art (SOTA) approaches of recommendation generation, the SCEFR system informed by user’s shopping preferences demonstrated superiority
Wissensproduktion und Wissenstransfer: Wissen im Spannungsfeld von Wissenschaft, Politik, und Öffentlichkeit
No full textDie Wissenschaft sieht sich zunehmend mit der Anforderung konfrontiert, politik- und handlungsrelevantes Wissen bereitzustellen. Mit der Forderung nach risikosensibler und nutzenorientierter Forschung wird zugleich ein Rückgang an Vertrauen in die Wissenschaft beklagt. Aus diesem Spannungsfeld heraus ergeben sich vielfältige Fragen nach den Grundlagen, Möglichkeiten und Grenzen von Wissenschaft sowie nach der Bedeutung wissenschaftlicher Expertise für politische Entscheidungen. Die Beiträge des Bandes widmen sich diesem Fragenkomplex aus unterschiedlichen Perspektiven und ermöglichen so neue Einblicke in die Bedeutung des wissenschaftlichen Wissens und der Expertise für Gesellschaft und Politik.Prof. Dr. Frieder Meyer-Krahmer Grußwort Peter Krause, Torger Möller Vorwort: Die Förderinitiative »Wissen für Entscheidungsprozesse – Forschung zum Verhältnis von Wissenschaft, Politik und Gesellschaft« Friedhelm Neidhardt, Renate Mayntz, Peter Weingart, Ulrich Wengenroth Wissensproduktion und Wissenstransfer. Zur Einleitung I. Wissensproduktion Ralf Adelmann, Jochen Hennig, Martina Hessler Visuelle Wissenskommunikation in Astronomie und Nanotechnologie. Zur epistemischen Produktivität und den Grenzen von Bildern Gabriele Gramelsberger Computersimulationen – Neue Instrumente der Wissensproduktion Falk Schützenmeister Disziplinarität und Interdisziplinarität in der atmosphärischen Chemie Rüdiger Wink Wissenschaftspolitik als Standortpolitik? Stammzellpolitik als Beispiel der Steuerung kontroversen Wissens durch nationale Politik Jochen Gläser, Stefan Lange, Grit Laudel, Uwe Schimank Evaluationsbasierte Forschungsfinanzierung und ihre Folgen II. Wissenstransfer Cordula Kropp, Jost Wagner Wissensaustausch in Entscheidungsprozessen: Kommunikation an den Schnittstellen von Wissenschaft und Agrarpolitik Stefan Böschen, Karen Kastenhofer, Ina Rust, Jens Soentgen, Peter Wehling Entscheidungen unter Bedingungen pluraler Nichtwissenskulturen Kathrin Braun, Svea Luise Herrmann, Sabine Könninger, Alfred Moore Die Sprache der Ethik und die Politik des richtigen Sprechens. Ethikregime in Deutschland, Frankreich und Großbritannien Alexander Bogner, Wolfgang Menz, Wilhelm Schumm Ethikexpertise in Wertkonflikten. Zur Produktion und politischen Verwendung von Kommissionsethik in Deutschland und Österreich Hans Peter Peters, Harald Heinrichs, Arlena Jung, Monika Kallfass, Imme Petersen Medialisierung der Wissenschaft als Voraussetzung ihrer Legitimierung und politischen Relevanz Andreas Knie, Dagmar Simon, Holger Braun-Thürmann, Gerd Möll, Heike Jacobsen Entrepreneurial Science? Typen akademischer Ausgründungen Bernd Beckert, Susanne Bührer, Ralf Lindner Verläufe und Motive von »Seitenwechseln«: Intersektorale Mobilität als Form des Wissenstransfers zwischen Forschung und Anwendung Zu den Autorinnen und Autore
TourExplain: A Crowdsourcing Pipeline for Generating Explanations for Groups of Tourists
No full textWhen a group is traveling together it is challenging to recommendan itinerary consisting of several points of interest (POIs). Thepreferences of individual group members often diverge, but it isimportant to keep everyone in the group satisfied during the entiretrip. We propose a method to consider the preferences of all thepeople in the group. Building on this method, we design expla-nations for groups of people, to help them reach a consensus forplaces to visit. However, one open question is how to best formu-late explanations for such sequences. In this paper, we introduceTourExplain, an automated crowdsourcing pipeline to generate andevaluate explanations for groups with the aim of improving ourinitial proposed explanations by relying on the wisdom of crowds.Accepted author manuscriptWeb Information System
Lord Byrons poetische Werke in acht Bänden /
No full textv. 1, Ritter Harolds Pilgerfahrt. Der Giaur.--v. 5, Manfred. Marino Faliero. Himmel und Erde. Sardanapal.--v. 6, Die beiden Foscari. Kain. Der umgestalte ungestalte. Werner.--v. 7, Don Juan, übersetzt von Alexander Neidhardt, 1. bis. 7. Gefang.--v. 8, Don Juan ... 8. bis 16. Gefang.Mode of access: Internet
Monitoring Gravitational Deformations of the Wettzell 20 m Radio Telescope’s Main Reflector Using a Leica RTC360
No full text[EN] Quasars are nowadays the basis to determine the world’s absolute orientation in space by radio interferometry (VLBI). The global network of baselines measured by the used radio telescopes, which vary greatly in size, is subject to various influences that have an impact on the International Terrestrial Reference Frame. Among others, those influences are imperfections of individual panels of the dishes, a possible elevation dependent deformation of the whole dish and a shift of the reference point due to gravitational influences. In this study, we monitor the elevation dependent deformation of the main reflector of the 20 m radio telescope of the Geodetic Observatory Wettzell by a Leica RTC360 laser scanner. For this task, we mount the terrestrial laser scanner overhead near the subreflector to capture the surface of the moving dish at each elevation angle. This study focusses on 1) introducing further redundancy in the measurement and processing strategy to gain a reliable and accurate result even the used scanner is a no high-end one. This furthermore leads to 2) investigations whether there are differences in the results between in related work used high-end scanners and the RTC360 and thus 3) whether the RTC360 proves to be capable to detect deformations at a radio telescope’s main reflector. Using these three foci, we show that deformations in the main reflector between elevations can be reliably determined areal and in focal length by redundant measurements with the RTC360. It is also shown that the results are less sensitive to axis errors compared to those obtained with high-end scanners. However, the compensations also show that the application scanner has certain systematics, which must be investigated in further steps.Weinhuber, A.; Neidhardt, A.; Holst, C. (2023). Monitoring Gravitational Deformations of the Wettzell 20 m Radio Telescope’s Main Reflector Using a Leica RTC360. En 5th Joint International Symposium on Deformation Monitoring (JISDM 2022). Editorial Universitat Politècnica de València. 447-454. https://doi.org/10.4995/JISDM2022.2022.13902OCS44745
Ethikexpertise in Wertkonflikten. Zur Produktion und politischen Verwendung von Kommissionsethik in Deutschland und Österreich.
No full textIn: Mayntz, R.; Neidhardt, F.; Weingart, P.; Wengenroth, U. (Hrsg.), Wissensproduktion und Wissenstransfer. Wissen im Spannungsfeld von Wissenschaft, Politik und Öffentlichkeit; Bielefeld: transcript, S. 243-268</i
Impact of terrestrial datum on the estimation of Earth Orientation Parameters by geodetic VLBI
No full textThe benefits of the Australian mixed-mode program (2018 - 2023) for the celestial reference frame at S/X-band
No full textThe current realization of the International Celestial Reference Frame at 8.4 GHz, the ICRF3-SX, is computed from very long baseline interferometry (VLBI) measurements starting in 1979 through until March 2018. The concentration of the majority of VLBI telescopes in the Northern hemisphere reflects itself in the unequal distribution of observations to radio sources over declination, causing the ICRF3-SX to be weaker in the south. One of the current VLBI observing programs active in the Southern hemisphere is the Australian mixed-mode program (AUM) which started to be organized in July 2018. In this contribution, we show the benefits of the AUM for the celestial reference frame including observation until December 2022 and also discuss its current limitations. The individual sessions were scheduled for currently available VLBI telescopes (Hb, Ke, Yg for the first block, then also including Ht and Ww in the second block). In terms of scheduling, the sessions were scheduled geodetically, i.e. aiming for a high number of scans. In AUM049-058, five target sources were observed in 4-5 scans of 10 minutes duration. This setup still ensures about 25 scans/hr/station, which is seen as a foundation for good geodetic results
Imaging, Modelfitting, and Source Structure Corrections for the K-band (24 GHz) Celestial Reference Frame
No full textThe K-band (24-GHz) celestial reference frame (K-CRF) program, supported through the United States Naval Observatory’s (USNO) 50% timeshare allocation of the Very Long Baseline Array (VLBA), has so far provided high-resolution VLBA images for more than 800 Active Galactic Nuclei (AGN) at up to 81 epochs, as part of extending the International Celestial Reference Frame (ICRF) to K-band. A comprehensive analysis of these images has yielded metrics that serve as indicators for the suitability of each source as a calibrator or reference point. Additionally, our modelling efforts provide crucial insights into the overall dimensions and orientation of the source structure. Although AGN such as the Celestial Reference Frame (CRF) sources typically appear more compact at K-band than at X-band (8.4 GHz), they can, on occasion, still display noticeable extended emissions at K-band. We therefore initiated a project aimed at modelling structure effects in the astrometric analysis process. This involves utilizing readily available K-CRF VLBI images and up-to-date source structure models. This paper offers an overview of our image analysis efforts and outlines our plans to investigate the impact of source structure using all available K-CRF sources
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