523 research outputs found
Compact SiPM based Detector Module for Time-of-Flight PET/MR
No full textWe present a compact detector module for gamma detection in the PET part of a simultaneous ToF-PET/MR system. The module covers an area of 3.3cm x 3.3cm with 64 SiPM based readout channels. It is composed of a stack of three PCBs of identical size: The SiPMs on the topmost PCB are read out by two full-custom ASICs located on a second PCB located underneath. A third PCB at the bottom of the stack contains a local voltage regulator, an FPGA for ASIC control and data processing, and DACs to generate bias voltages for the readout ASICs and the SiPM devices. An LYSO scintillator block is optically coupled to the SiPMs for gamma to light conversion
Entwicklung einer schnellen Pulsformanalyse für asymmetrische AGATA-Germanium-Detektoren
No full textOnTEAM metadata: GDSID: DOC-2007-May-32; Attribute ID: LIBRARY-thesis_diss-2007-005; Title: [GSI Diss 2007-05] Entwicklung einer schnellen Pulsformanalyse für asymmetrische AGATA-Germanium-Detektoren; Author(s): Beck, Torsten; Corporate author(s): ; Publication date: 20070501; Creator: manton; Creation date: 15.05.2007 16:02:12; Change date: 29.10.2008 16:29:34; Access: nur berechtigte Gruppen; Attribute type: Text.Thesis.Diss; Directory path: ['GSI Publications', 'GSI as Publisher']; Attribute path: ['Infrastructure', 'Library and Documentation', 'thesis_diss', 'Added in 2007']; File name(s): ['DOC-2007-May-32-1.pdf']; File title(s): ['']; File access: ['nur berechtigte Gruppen'
Manifolds, sheaves, and cohomology
No full textThis book explains techniques that are essential in almost all branches of modern geometry such as algebraic geometry, complex geometry, or non-archimedian geometry. It uses the most accessible case, real and complex manifolds, as a model. The author especially emphasizes the difference between local and global questions. Cohomology theory of sheaves is introduced and its usage is illustrated by many examples. Content Topological Preliminaries - Algebraic Topological Preliminaries - Sheaves - Manifolds - Local Theory of Manifolds - Lie Groups - Torsors and Non-abelian Cech Cohomology - Bundles - Soft Sheaves - Cohomology of Complexes of Sheaves - Cohomology of Sheaves of Locally Constant Functions - Appendix: Basic Topology, The Language of Categories, Basic Algebra, Homological Algebra, Local Analysis Readership Graduate Students in Mathematics / Master of Science in Mathematics About the Author Prof. Dr. Torsten Wedhorn, Department of Mathematics, Technische Universität Darmstadt, Germany
James Watson, Maclyn McCarty, and Torsten Wiesel
No full textTorsten Wiesel (right) with Professor Emeritus Maclyn McCarty (center), co-author of the paper with Oswald Avery and Colin MacLeod, and James D. Watson, director of Cold Spring Harbor Laboratory, 1994
Photo by Leif Carlsson
To commemorate the fiftieth anniversary of the discovery at The Rockefeller University that genes are made of DNA - considered by many to be the single most important biological discovery of the twentieth century - the university has kicked off a year-long series of events that were running through May 1994. The celebration was formally inaugurated in November 1993 with a lecture by Nobel laureate James D. Watson, best known for discovering the double-helical structure of DNA.
See also Search Winter 1994, vol. 4, no. 1https://digitalcommons.rockefeller.edu/group-portraits/1013/thumbnail.jp
Seltsame Schauspiele. Torsten Fogelqvists Deutschlandreise 1934
No full textIn 1934 Torsten Fogelqvist, a prominent member of the Swedish Academy and a well-known journalist and intellectual, visits Nazi Germany. He writes about his visit to the Third Reich in 17 articles published in the Stockholm daily newspaper Dagens Nyheter. The author, highly critical of the Hitler regime, scrutinizes several aspects of the nazified German society such as the attempts to re-educate the German citizen in accordance with the ideology of the new regime, the hero cult in the Nazi movement, and the relationship between the German state and the churches. In order to further an understanding of political and social developments in Germany Fogelqvist uses a specific strategy. He “translates” them into an imaginary Swedish context. This paper compares his views with those of other Swedish visitors
Entwicklung einer Methode zur objektiven Bestimmung der Streulichtwahrnehmung
No full textEtwa 80 % der zur Interaktion mit der Umwelt anfallenden Informationen werden durch das visuelle System des Menschen verarbeitet. Im Laufe des natürlichen Alterungsprozesses entsteht eine Beeinträchtigung der Qualität des Sehens. Die Minderung der Sehqualität erfolgt durch physiologische Prozesse sowie pathologische Veränderungen. Die größte Beeinträchtigung entsteht durch die natürliche Alterung und die damit einhergehende Trübung der Augenlinse (Katarakt). Die Trübung der Linse führt zu einer Zunahme an intraokularem Streulicht. Die resultierende Zunahme der Streulichtwahrnehmung äußert sich in einer Abnahme der Sehleistung (Abnahme des retinalen Kontrasts) und Effekten von Blendung. Im Rahmen der vorliegenden Dissertation wurde eine Methode entwickelt, die eine quantitativ objektive Beschreibung der Streulichtwahrnehmung ermöglicht. Dazu wurde ein auf dem V-Modell basierendes generisches Prozessmodell entwickelt. Anhand dieses Modells wurde eine psychophysische Messmethode in eine objektive elektrophysiologische Messmethode transferiert. Im Entwicklungsprozess wurden Anforderungen an die Methodik abgeleitet und deren Verifikation und Validierung mittels jeweiliger Prozessschritte des Modells implementiert. Das entwickelte Konzept zur Bestimmung der Streulichtwahrnehmung basiert auf der Ermittlung der äquivalenten Schleierleuchtdichte. Dazu erfolgt die Abbildung von Kompensationsprozessen der Schleierleuchtdichte mittels visuell evozierten Potentialen. In Probandenstudien wurden die Charakteristika der zur Anwendung der Methodik notwendigen Einzelkomponenten analysiert und deren Überführung in die integrierte Messmethodik verifiziert. Abschließend wurde die entwickelte Methodik durch einen Systemvergleich mit dem Stand der Technik, dem C-Quant der Firma Oculus Optikgeräte (Oculus Optikgeräte GmbH, Wetzlar, Deutschland) validiert. Die klinische Relevanz wurde anhand der Unterscheidung zwischen drei Bereichen der Streulichtwahrnehmung, der physiologischen Streulichtwahrnehmung, physiologisch erhöhten Streulichtwahrnehmung und pathologisch erhöhten Streulichtwahrnehmung nachgewiesen.About 80% of the information from interaction with the environment is processed by the human visual system. As people age, the vision quality declines due to physiological and pathological changes. The main factor is the aging progress of the human lens, causing cataracts and increased intraocular stray light. This leads to reduced visual performance and increased glare sensitivity. This dissertation presents the development of a method for the quantitative and objective assessment of stray light perception. A generic process model based on the V-model was developed. Using this model, a psychophysical measurement principle was transferred into an objective electrophysiological measurement method. Requirements for the method were derived and their verification and validation were implemented using the respective process steps of the process model. The developed concept for evaluation the stray light perception is based on the determination the equivalent veiling luminance. Therefore, compensation processes of the veiling luminance are recorded using visual evoked potentials. In subject studies, the characteristics of the components of the concept were analyzed and their transfer into the integrated measurement method was verified. Finally, the developed methodology was validated by a system comparison with the state of the art, the C-Quant from Oculus Optikgeräte (Oculus Optikgeräte GmbH, Wetzlar, Germany). The clinical relevance of the method was demonstrated by distinguishing between three categories of stray light perception: physiological stray light perception, physiologically increased stray light perception, and pathologically increased stray light perception
PISM glacial cycle sensitivity experiments of the Antarctic Ice Sheet
No full textThis dataset contains PISM simulation results (http://www.pism-docs.org) of the Antarctic Ice Sheet based on code release v1.0-paleo-ensemble (https://doi.org/10.5281/zenodo.3574033). PISM is the open-source Parallel Ice Sheet Model developed mainly at UAF, USA and PIK, Germany.
With the help of added python scripts, all figures can be reproduced as in the journal publication:
- Albrecht et al., 2020, doi:10.5194/tc-14-599-2020.
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Data:
Find PISM results as netCDF data. See 'README.md' for a list of all performed experiment.
All forcing input data for the experiments and plots can be downloaded and remapped via https://github.com/pism/pism-ais. Some of the original input data files are freely available, for others please contact the author or the corresponding data publisher.
Figure plotting scripts (jupyter notebook based on python, see https://jupyter.org) in 'plot_scripts' access the uploaded PISM results in 'model_data' and save the plots to 'final_figures'. Jupyter notebook can be run in the browser and shared, see https://nbviewer.jupyter.org/url/www.pik-potsdam.de/~albrecht/notebooks/paleo_paper/paleo_paper_final.ipynb.
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Contact:
Albrecht, Torsten ([email protected]) ; Potsdam-Institute for Climate Impact Research (PIK), Potsdam, German
Die Erfolgsfaktoren für unternehmerisches E-Mail-Marketing nach Dr. Torsten Schwarz am Praxisbeispiel ERGOTOPIA GmbH
No full textThis scientific document reveals the results of an empirical examination within the realm of entrepreneurial e-mail-marketing which is based on a literature review by technical author Dr. Torsten Schwarz. Using the start-up company ERGOTOPIA as a practical example, the author of the master thesis investigates whether the explanations of Dr. Schwarz match with the practical implementation of ERGOTOPIA.
Precisely, the scientific paper focuses on the examination of the four aspects lead generation, newsletter-design, software-requirements and performance measurement through monitoring with regard to successful realization of e-mail-marketing campaigns. The empirical part of this examination is made of the introduction as well as the analysis of two conducted so called split-tests that compare specific aspects of the newsletter-design and measure data-driven results to show which kind of aspect produced the more successful campaign.
This way the author proves whether the recommendations by Dr. Schwarz are practically relevant for the company ERGOTOPIA
First results with SiPM tiles for TOF PET based on FBK RGB-HD technology
No full textWe present the first results of timing and energy resolution of two newly developed tiles based on FBK RGB-HD SiPMs
Performance of FBK SiPMs coupled to PETA3 read-out ASIC for PET application
No full textIn this paper we show the energy and timing resolution performances of FBK SiPMs coupled to the PETA3 ASIC for PET application. We developed a measurement set-up to characterize single SiPMs coupled to scintillator exploiting the detector stack developed within the HYPERImage project. In this way we are able to characterize the combined SiPM/ASIC performance with the same signal chain (from the sensor to the ASIC board) used in the PET system. We show that using two scintillator detectors, composed of a 3x3x5mm^3 LYSO crystal coupled to a 3x3mm^2 SiPM, an intra-stack CRT of about 200ps FWHM can be obtained
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