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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.
261

Static analyses over weak memory

Nimal, Vincent P. J. January 2014 (has links)
Writing concurrent programs with shared memory is often not trivial. Correctly synchronising the threads and handling the non-determinism of executions require a good understanding of the interleaving semantics. Yet, interleavings are not sufficient to model correctly the executions of modern, multicore processors. These executions follow rules that are weaker than those observed by the interleavings, often leading to reorderings in the sequence of updates and readings from memory; the executions are subject to a weaker memory consistency. Reorderings can produce executions that would not be observable with interleavings, and these possible executions also depend on the architecture that the processors implement. It is therefore necessary to locate and understand these reorderings in the context of a program running, or to prevent them in an automated way. In this dissertation, we aim to automate the reasoning behind weak memory consistency and perform transformations over the code so that developers need not to consider all the specifics of the processors when writing concurrent programs. We claim that we can do automatic static analysis for axiomatically-defined weak memory models. The method that we designed also allows re-use of automated verification tools like model checkers or abstract interpreters that were not designed for weak memory consistency, by modification of the input programs. We define an abstraction in detail that allows us to reason statically about weak memory models over programs. We locate the parts of the code where the semantics could be affected by the weak memory consistency. We then provide a method to explicitly reveal the resulting reorderings so that usual verification techniques can handle the program semantics under a weaker memory consistency. We finally provide a technique that synthesises synchronisations so that the program would behave as if only interleavings were allowed. We finally test these approaches on artificial and real software. We justify our choice of an axiomatic model with the scalability of the approach and the runtime performance of the programs modified by our method.
262

A kinetic study of the degradation of hyaluronic acid at high concentrations of sodium hydroxide

Lekander, Maria, Fagerström Troncoso, Jonathan, Idjbara, Abdelrahman, Karlsson, Ida, Lindgren, Teresia, Ström, Simon January 2016 (has links)
During production of different Hyaluronic acid (HA) products Galderma use a high concentration of NaOH in the crosslinking process of HA. HA’s degradation kinetics are widely unknown at higher pH’s and is interesting for the future of product development of HA. Static Light Scattering (SLS) was used to determine the weight average molecular weight (MW ) of samples with four different NaOH concentrations, four temperatures, three reaction times and one t0  sample. The results were evaluated in forms of Arrhenius-graphs for different NaOH concentrations, the activation energy (EA ) with respect to pH and the reaction rate for each temperature with respect to NaOH concentration. It was found that the degradation of HA was more strongly affected by temperature than by NaOH concentration and that the EA  did not show any significant signs of change between higher concentrations of NaOH.
263

Dynamic WIFI Fingerprinting Indoor Positioning System

Reyes, Omar Costilla 08 1900 (has links)
A technique is proposed to improve the accuracy of indoor positioning systems based on WIFI radio-frequency signals by using dynamic access points and fingerprints (DAFs). Moreover, an indoor position system that relies solely in DAFs is proposed. The walking pattern of indoor users is classified as dynamic or static for indoor positioning purposes. I demonstrate that the performance of a conventional indoor positioning system that uses static fingerprints can be enhanced by considering dynamic fingerprints and access points. The accuracy of the system is evaluated using four positioning algorithms and two random access point selection strategies. The system facilitates the location of people where there is no wireless local area network (WLAN) infrastructure deployed or where the WLAN infrastructure has been drastically affected, for example by natural disasters. The system can be used for search and rescue operations and for expanding the coverage of an indoor positioning system.
264

Feedback Stabilization of Inverted Pendulum Models

Cox, Bruce 01 January 2005 (has links)
Many mechanical systems exhibit nonlinear movement and are subject to perturbations from a desired equilibrium state. These perturbations can greatly reduce the efficiency of the systems. It is therefore desirous to analyze the asymptotic stabilizability of an equilibrium solution of nonlinear systems; an excellent method of performing these analyses is through study of Jacobian linearization's and their properties. Two enlightening examples of nonlinear mechanical systems are the Simple Inverted Pendulum and the Inverted Pendulum on a Cart (PoC). These examples provide insight into both the feasibility and usability of Jacobian linearizations of nonlinear systems, as well as demonstrate the concepts of local stability, observability, controllability and detectability of linearized systems under varying parameters. Some examples of constant disturbances and effects are considered. The ultimate goal is to examine stabilizability, through both static and dynamic feedback controllers, of mechanical systems
265

Efekt konzervativní terapie u deformity hallux valgus / Effect of conservative therapy to deformity hallux valgus

Levá, Helena January 2015 (has links)
This thesis focuses on the evaluation of a conservative approach to the hallux valgus deformity. 21 people took part in the empirical study in which the changes were tracked. I worked with a group of women who exercised regularly and a control group. The regularly exercising group participated in a 3-month therapeutic program led by a physiotherapist. Each of the participants was properly examined at the beginning of the program and after three months, when the program finished. Each examination consisted of a kinesiologic analysis, a plantography footprint, a foot X-ray, a pain evaluation (the numeric scale was used) and filling out a scoring scale questionnaire of American Orthopaedic Foot and Ankle Society (AOFAS). The changes of pain of the MTP or IP toe joint, the development of foot arch, changes of the toe valgus angle according to the X-rays and the overall score achieved in the AOFAS questionnaire were statistically evaluated. The ability to isolate toe abduction, right posture of the foot, stability of the axial joints and other changes were followed as well. After comparing the results the conclusion of the study is that the three-months physiotherapist-led program weaken the pain of MTP/IP toe joint, rise the score achieved in the AOFAS questionnaire, improve the foot posture and the overall...
266

Bobox Runtime Optimization / Bobox Runtime Optimization

Krížik, Lukáš January 2015 (has links)
The goal of this thesis is to create a tool for an optimization of code for the task-based parallel framework called Bobox. The optimizer tool reduces a number of short and long running tasks based on a static code analysis. Some cases of short-running tasks cause an unnecessary scheduling overhead. The Bobox scheduler can schedule a task even though the task does not have all input data. Unless, the scheduler has enough information not to schedule such task. In order to remove such short-running task, the tool analyses its input usage and informs the scheduler. Long-running tasks inhibit a parallel execution in some cases. A bigger task granularity can significantly improve execution times in a parallel environment. In order to remove a long-running task, the tool has to be able to evaluate a runtime code complexity and yield a task execution in the appropriate place. Powered by TCPDF (www.tcpdf.org)
267

Statická analýza programů v C# / Static analysis of C# programs

Malý, Petr January 2014 (has links)
The goal of this diploma thesis is to study and implement selected methods of static code analysis for C# programs translated into the Common Intermediate Language. The results of this work are integrated into the ParallaX Development Environment system. This diploma thesis focuses on Structural, Points-to and Dependence. analysis. Powered by TCPDF (www.tcpdf.org)
268

Implementace rezoluce řízení toku v dynamickém jazyce / Implementing control flow resolution in dynamic language

Šindelář, Štěpán January 2014 (has links)
Dynamic programming languages allow us to write code without type information and types of variables can change during execution. Although easier to use and suitable for fast prototyping, dynamic typing can lead to error prone code and is challenging for the compilers or interpreters. Programmers often use documentation comments to provide the type information, but the correspondence of the documentation and the actual code is usually not checked by the tools. In this thesis, we focus on one of the most popular dynamic programming languages: PHP. We have developed a framework for static analysis of PHP code as a part of the Phalanger project -- the PHP to .NET compiler. The framework supports any kind of analysis, but in particular, we implemented type inference analysis with emphasis on discovery of possible type related errors and mismatches between documentation and the actual code. The implementation was evaluated on real PHP applications and discovered several real errors and documentation mismatches with a good ratio of false positives. Powered by TCPDF (www.tcpdf.org)
269

Vliv pasívního protažení svalu na aktuální psychický stav pacienta / Effect of passive stretching on current patient's mental state

Vagenknechtová, Anna January 2013 (has links)
Title: Effect of passive stretching on current patient's mental state Objectives: This thesis presents a pilot theoretical - empirical experiment, where the main subject of the experiment is to evaluate the effect of passive stretching hypertonic or shortened muscles, i.e. decreased muscle tone on current patient's mental state. The theoretical part summarizes the neurophysiologic basis of emotions by search form. Through the implementation and follow-up experiment, we aim to demonstrate the positive impact of stretching exercise on current psychological state. Methods: Two groups of patients participated in this research, thirty without pain and thirty with pain. We chose questionnaire PANAS-X (Watson, Clark, 1994) to diagnose their current mental state. The first group, patients without pain, completed the questionnaire before and immediately after the experimental intervention, i.e. passive stretching hypertonic muscles. The second group, patients with pain, went through stretching exercise unit twice a week for three weeks. As for this group, we compare the situation before the first therapy with the state after six sessions. We evaluated the change in the individual sublevels of positive and negative emotions by the methodology of the questionnaire. Results: During the experiment three out of...
270

Akutní vliv statického a dynamického strečinku na výskok / Acute effect of static and dynamic stretching on vertical jump

Dostálová, Anna January 2017 (has links)
Title Acute effect of static and dynamic stretching on vertical jump. Objectives The aim of this thesis is to assess whether it is better to warm up by static or dynamic stretching in order to improve performance in the vertical jump. Methods The first part of this thesis is theoretical and is the basis for measurement, which is described in the second part. The tested set consists of ten women volleyball players. Each player underwent three vertical jump measurements on power plates Kistler, which recorded flight time of the player over the plates. All measurements were evaluated afterwards. Five attempts were recorded in each measurement. Measurements were carried out without stretching, after dynamic stretching and after static stretching. The thesis includes a survey that monitors the perception of the players` performance. Results Results of the total tested set measurement show that inclusion of dynamic stretching during the warm up leads to a slight decline in the physical performance. This decrease presents about 0.92%. Another conclusion of this research is that the inclusion of static stretching to the warm up also results in a slight decrease in the athletic performance. In this case the decrease is about 1.72%. In a direct comparison of these two types of stretching, the inclusion of...

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