Datenanalyse für das CRESST Experiment: Neue Methoden, verbesserte Alphaanalyse, und neue Ergebnisse bezüglich Dunkler Materie und Untergrund

The CRESST experiment aims to detect dark matter-nucleus scattering with crystal-based, cryogenic detectors. The present work contains an α analysis of CRESST data collected between 2013 and 2015 and a dark matter analysis of the 2016/7 data set with a focus on the understanding of backgrounds. The α analysis provides input for background simulations. The dark matter analysis achieved leading limits on the dark matter- nucleon interaction cross-section for O(100MeV/c2) dark matter masses.Das CRESST Experiment versucht Dunkle Materie über ihre Streuung an Atomkernen in einem kryogenen Detektorsetup nachzuweisen. In der vorliegenden Arbeit werden eine Alphaanalyse des zwischen 2013 und 2015 aufgenommen Datensets sowie die Dunkle Materie Analyse des Datensets von 2016/7 beschrieben. Die Alphaanalyse ist ein wichtiger Beitrag für Untergrundsimulationen. Die Dunkle Materie Analyse ergab führende Limits für den Dunkle Materie-Nukleon Wechselwirkungsquerschnitt bei Dunklen Materie Massen im O(100MeV/c2) Bereich

Mobile Ad Hoc Networks

Guiding readers through the basics of these rapidly emerging networks to more advanced concepts and future expectations, Mobile Ad hoc Networks: Current Status and Future Trends identifies and examines the most pressing research issues in Mobile Ad hoc Networks (MANETs). Containing the contributions of leading researchers, industry professionals, and academics, this forward-looking reference provides an authoritative perspective of the state of the art in MANETs. The book includes surveys of recent publications that investigate key areas of interest such as limited resources and the mobility of mobile nodes. It considers routing, multicast, energy, security, channel assignment, and ensuring quality of service. Also suitable as a text for graduate students, the book is organized into three sections: Fundamentals of MANET Modeling and Simulation—Describes how MANETs operate and perform through simulations and models Communication Protocols of MANETs—Presents cutting-edge research on key issues, including MAC layer issues and routing in high mobility Future Networks Inspired By MANETs—Tackles open research issues and emerging trends Illustrating the role MANETs are likely to play in future networks, this book supplies the foundation and insight you will need to make your own contributions to the field. It includes coverage of routing protocols, modeling and simulations tools, intelligent optimization techniques to multicriteria routing, security issues in FHAMIPv6, connecting moving smart objects to the Internet, underwater sensor networks, wireless mesh network architecture and protocols, adaptive routing provision using Bayesian inference, and adaptive flow control in transport layer using genetic algorithms

Mobile Ad Hoc Networks

Guiding readers through the basics of these rapidly emerging networks to more advanced concepts and future expectations, Mobile Ad hoc Networks: Current Status and Future Trends identifies and examines the most pressing research issues in Mobile Ad hoc Networks (MANETs). Containing the contributions of leading researchers, industry professionals, and academics, this forward-looking reference provides an authoritative perspective of the state of the art in MANETs. The book includes surveys of recent publications that investigate key areas of interest such as limited resources and the mobility of mobile nodes. It considers routing, multicast, energy, security, channel assignment, and ensuring quality of service. Also suitable as a text for graduate students, the book is organized into three sections: Fundamentals of MANET Modeling and Simulation—Describes how MANETs operate and perform through simulations and models Communication Protocols of MANETs—Presents cutting-edge research on key issues, including MAC layer issues and routing in high mobility Future Networks Inspired By MANETs—Tackles open research issues and emerging trends Illustrating the role MANETs are likely to play in future networks, this book supplies the foundation and insight you will need to make your own contributions to the field. It includes coverage of routing protocols, modeling and simulations tools, intelligent optimization techniques to multicriteria routing, security issues in FHAMIPv6, connecting moving smart objects to the Internet, underwater sensor networks, wireless mesh network architecture and protocols, adaptive routing provision using Bayesian inference, and adaptive flow control in transport layer using genetic algorithms

Bayesian Uncertainty Quantification of Physical Models in Thermal-Hydraulics System Codes

Nuclear thermal-hydraulics (TH) system codes use several parametrized physical or empirical models to describe complex two-phase flow phenomena. The reliability of their predictions is as such primarily affected by the uncertainty associated with the parameters of the models. Because these model parameters often cannot be measured, nor have inherent physical meanings, their uncertainties are mostly based on expert judgment. The present doctoral research aims to quantify the uncertainty of physical model parameters implemented in a TH system code based on experimental data. Specifically, this thesis develops a methodology to use experimental data to inform these uncertainties in a more objective manner. The methodology is based on a probabilistic framework and consists of three steps adapted from recent developments in applied statistics: global sensitivity analysis (GSA), metamodeling, and Bayesian calibration. The methodology is applied to reflood experiments from the FEBA separate effect test facility (SETF), which are modeled with the TH system code TRACE. Reflood is chosen as a relevant phenomenon for the safety analysis of light water reactors (LWRs) and three typical time-dependent outputs are investigated: clad temperature, pressure drops and liquid carryover. First, GSA allows screening out input parameters that have a low impact on the reflood transient. Functional data analysis (FDA) is then used to reduce the dimensionality of the time-dependent code outputs, while preserving their interpretability. The resulting quantities can be used once more with GSA to investigate, quantitatively, the effect of the input parameters on the overall time-dependent outputs. Second, a Gaussian process (GP) metamodel is developed and validated as a surrogate for the TRACE model. The average prediction error of the metamodel is sufficiently low to predict all considered outputs, and its computational cost is less than 5 [s] as compared to 6â15 [min] per TRACE run. Third and finally, the a posteriori model parameter uncertainties are quantified by calibration on a selected test from the FEBA experiments. Several posterior probability density functions (PDFs) corresponding to different calibration schemes â with and without model bias term and for different types of output â are formulated and directly sampled using a Markov Chain Monte Carlo (MCMC) ensemble sampler and the GP metamodel. The posterior samples are then propagated in a set of FEBA experiments to check the validity of the posterior model parameter values and uncertainties. The calibration is performed on different types of output to inform model parameters that would have otherwise remained non-identifiable. The calibration scheme with model bias term is able to constrain the prior uncertainties of the model parameters while keeping the nominal TRACE parameters values within the posterior uncertainty interval. That is in contrast with the results of the calibration without model bias term, in which the posterior uncertainties are concentrated on either side of the prior range, and at times do not include the nominal TRACE parameters values. The methodology was shown to successfully inform the uncertainty of the model parameters involved in a reflood transient. In the future, the methodology can be applied to model parameters involved in other TH phenomena using data from SETFs and contributes to achieve the goal of quantifying uncertainties in the safety assessment of LWRs

Renewable Energy

The demand for secure, affordable and clean energy is a priority call to humanity. Challenges associated with conventional energy resources, such as depletion of fossil fuels, high costs and associated greenhouse gas emissions, have stimulated interests in renewable energy resources. For instance, there have been clear gaps and rushed thoughts about replacing fossil-fuel driven engines with electric vehicles without long-term plans for energy security and recycling approaches. This book aims to provide a clear vision to scientists, industrialists and policy makers on renewable energy resources, predicted challenges and emerging applications. It can be used to help produce new technologies for sustainable, connected and harvested energy. A clear response to economic growth and clean environment demands is also illustrated

Microgravity science & applications. Program tasks and bibliography for FY 1995

This annual report includes research projects funded by the Office of Life and Microgravity Sciences and Applications, Microgravity Science and Applications Division, during FY 1994. It is a compilation of program tasks (objective, description, significance, progress, students funded under research, and bibliographic citations) for flight research and ground based research in five major scientific disciplines: benchmark science, biotechnology, combustion science, fluid physics, and materials science. Advanced technology development (ATD) program task descriptions are also included. The bibliography cites the related principle investigator (PI) publications and presentations for these program tasks in FY 1994. Three appendices include a Table of Acronyms, a Guest Investigator index and a Principle Investigator index