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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Semiconductor detectors for the inner tracker of the ATLAS experiment at CERN

Morgan, Debbie January 1998 (has links)
No description available.
32

Development of ring imaging Cherenkov detectors for the LHCb experiment

John, Malcolm Jared James January 2001 (has links)
No description available.
33

Atomic force microscopy : atomic resolution imaging and force-distance spectroscopy

Grimble, Ralph Ashley January 1999 (has links)
No description available.
34

Testování výkonu za běhu v Javě / Run-time performance testing in Java

Kotrč, Jaroslav January 2015 (has links)
This work focuses on relative comparisons of individual methods performance. It is based on Stochastic Performance Logic, which allows to express, for example, that one method runs at most two times longer than another method. This results are more portable than absolute values. It extends standard unit tests with performance assumptions, which are evaluated during actual run-time of a released application. Dynamically added and removed instrumentation is used for automatic modification of the production code. Instrumentation part uses DiSL framework to be able to seamlessly measure even Java system classes. Methods are measured sequentially, number of concurrently measured method is dynamically changed and measurement code is removed as soon as required data are obtained to avoid high overhead. The results show that for processor demanding application this approach may bring up to 3-times lower overhead peaks than measuring all methods at once. Powered by TCPDF (www.tcpdf.org)
35

Capturing Performance Assumptions using Stochastic Performance Logic / Capturing Performance Assumptions using Stochastic Performance Logic

Trojánek, Tomáš January 2013 (has links)
Performance testing is a mean used to evaluate speed of software projects. In an ideal state a project has a set of tests attached to it and such set may be repeat- edly executed in order to verify that all performance expectations are satisfied. The most widespread method of constructing these tests nowadays is based on measuring absolute time values. A test executes a chosen application unit and then compares the time it took to complete with a precise bound, which has been determined in advance. However, this approach has several disadvantages that affect reliability of such tests. First of all, the way in which those precise bounds should be established is not clear. And even if it is, then the bounds are tied to a certain hardware configuration. As a remedy, this thesis demonstrates a whole another approach, which is based on relative performance comparison. Using a logic built on top of a research published by the issuing department, chosen application units are compared together in a manner that makes results of such tests more reliable even to a change of hardware configuration. The presented theory is also implemented and verified on selected use cases. 1
36

End-to-end performance testing of a healthcare alarm system

Björn, Johansson January 2019 (has links)
Digital services involving large systems with multiple users are ubiquitous in modern society. The systems are often complicated and made up of multiple devices and communication protocols. A fundamental problem in this context is how the behavior of a system changes as the number of users vary. In particular, when do the systems’ resources saturate and how does the system behave when close to saturation. Performance testing is key for addressing this fundamental problem. Performance testing is the scope of this project. Performance tests can be used for inference of, for example, a system's scalability. Furthermore, it can be used to provide general guarantees on the services that can be delivered. Performance testing at the company Phoniro AB is considered. The platform Phoniro Care is the back-end service for the company’s products. The Phoiro 6000 system is one of the products that uses Phoniro Care. The system allows for multiple users and offers alarm services. The primary focus of this project is to determine the behavior of that system during varying levels of simulated load, and furthermore analyze the data extracted from such simulations and tests. The open source software JMeter was used as the tool for performance testing. It was selected from a set of candidate tools that have been evaluated in the literature based on various performance criteria. The results are presented by graphs showing the time evolution of different performance indicators. A conclusion from this work is that the implemented performance testing framework helps to answer questions about the systems’ behavior. Questions that are important for the company’s further development and expansion of the system. Furthermore, the proposed framework establishes a foundation for further inquiries on the subject.
37

Comparing different and inverter graph data structure / Comparativo de diferentes estruturas de dados de And-Inverter Graph

Bittencourt, Marcelo Corrêa de January 2018 (has links)
Este documento apresenta uma análise de desempenho de quatro diferentes implementações de And-Inverter Graph (AIG). AIGs são estruturas de dados normalmente utilizadas em programas que são utilizados para design de circuitos digitais. Diferentes implementações da mesma estrutura de dados pode afetar o desempenho. Isto é demonstrado em trabalhos anteriores que avaliam o desempenho de diferentes pacotes BDD (Binary Decision Diagram), que é outra estrutura de dados largamente utilizada em síntese lógica. Foram implementadas quatro estruturas de dados diferentes utilizando grafos unidirecionais ou bidirecionais aos quais os nodos são referenciados utilizando ponteiros ou índices de inteiros não-negativos. Utilizando estas diferentes estruturas de dados de AIG, medimos como diferentes aspectos das implementações afetam o desempenho da execução de um algoritmo básico. / This document presents a performance analysis of four different And-Inverter Graph (AIG) implementations. AIG is a data structure commonly used in programs used for digital circuits design. Different implementations of the same data structure can affect performance. This is demonstrated by previous works that evaluate performance for different Binary Decision Diagram (BDD) packages, another data structure widely used in logic synthesis. We have implemented four distinct AIG data structures using a choice of unidirectional or bidirectional graphs in which the references to nodes are made using pointers or indexed using non-negative integers. Using these different AIG data structures, we measure how different implementation aspects affect performance in running basic algorithm.
38

Effect of using Organosilane with Crumb Rubber Modified Hot Mix Asphalt Mixtures

January 2018 (has links)
abstract: Crumb rubber use in asphalt mixtures by means of wet process technology has been in place for several years in the United States with good performance record; however, it has some shortcomings such as maintaining high mixing and compaction temperatures in the field production. Organosilane (OS), a nanotechnology chemical substantially improves the bonding between aggregate and asphalt by modifying the aggregate structure from hydrophilic to hydrophobic contributing to increased moisture resistance of conventional asphalt mixtures. Use of Organosilane also reduces the mixing and compaction temperatures and facilitates similar compaction effort at lower temperatures. The objective of this research study was first to perform a Superpave mix design for Crumb Rubber Modified Binder (CRMB) gap-graded mixture with and without Organosilane; and secondly, analyse the performance of CRMB mixtures with and without Organosilane by conducting various laboratory tests. Performance Grade (PG) 64-22 binder was used to create the gap-graded Hot Mix Asphalt (HMA) mixtures for this study. Laboratory tests included rotational viscometer binder test and mixtures tests: dynamic modulus, flow number, tensile strength ratio, and C* fracture test. Results from the tests indicated that the addition of Organosilane facilitated easier compaction efforts despite reduced mixing and compaction temperatures. Organosilane also modestly increased the moisture susceptibility and resistance to crack propagation yet retaining equal rutting resistance of the CRMB mixtures. / Dissertation/Thesis / Masters Thesis Civil, Environmental and Sustainable Engineering 2018
39

The Effect of Various Body Positions on Performance of the Isometric Mid-Thigh Pull

Beckham, George K 01 August 2015 (has links)
The purpose of this dissertation was to evaluate the effects of changing body position on the execution of the isometric mid-thigh pull (IMTP). Furthermore, while there is evidence to suggest that there is an effect of familiarization on performance of maximal strength tests, there has been no known research evaluating the effect of learning on the IMTP. The effect of familiarization was assessed by evaluating changes in variables obtained from the IMTP. Subjects did not statistically improve over the five IMTP testing sessions, regardless of the body position used, or if subjects had previous experience with weightlifting derivatives. This may indicate that little familiarization is needed for subjects to perform the IMTP before acute increases due to learning stabilize. When body positions were compared, there were differences in force production whether subjects had or did not have experience with weightlifting movements. The magnitude of difference between body position was affected by weightlifting movement experience; lifters with >6 months experience with weightlifting had larger differences in force production between position. Average muscle activation for a variety of muscles, evaluated with surface EMG, appeared to differ between body positions, although these positions are idiosyncratic to experience level. In particular, lumbar erector spinae activation was higher in the bent position for both groups, which may have implications for low back injury risk.In entirety, it appears that if maximizing force production is the goal, the upright positon is optimal. Furthermore, the differing body positions have meaningfully different effects on how 3 much individual muscles are activated between positions. Lastly, substantial familiarization does not appear to be necessary before subjects perform the IMTP.
40

Effect of Body Position on Force Production During the Isometric Midthigh Pull

Beckham, George K., Sato, Kimitake, Santana, Hugo A. P., Mizuguchi, Satoshi, Haff, G. Gregory, Stone, Michael H. 01 January 2018 (has links)
Various body positions have been used in the scientific literature when performing the isometric midthigh pull resulting in divergent results. We evaluated force production in the isometric midthigh pull in bent (125° knee and 125° hip angles) and upright (125° knee, 145° hip angle) positions in subjects with (>6 months) and without (<6 months) substantial experience using weightlifting derivatives. A mixed-design ANOVA was used to evaluate the effect of pull position and weightlifting experience on peak force, force at 50, 90, 200, and 250 ms. There were statistically significant main effects for weightlifting experience and pull position for all variables tested, and statistically significant interaction effects for peak force, allometrically scaled peak force, force at 200 ms, and force at 250 ms. Calculated effect sizes were small to large for all variables in subjects with weightlifting experience, and were small to moderate between positions for all variables in subjects without weightlifting experience. A central finding of the study is that the upright body position (125° knee and 145° hip) should be used given that forces generated are highest in that position. Actual joint angles during maximum effort pulling should be measured to ensure body position is close to the position intended.

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