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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.
91

Expansion of the Equipment Allowance Pool at Twentynine Palms, California, using Reserve assets

O'Bryan, Patrick W., Malloy, Dennis J. 12 1900 (has links)
Approved for public release; distribution is unlimited / Static marginal analysis is applied to the Marin e Corps' proposed expansion of the Equipment Allowance Pool at Twentynine Palms, California, using Select Marine Corps Reserve assets. A formula is presented for determining potential equipment candidates. The formula is presented for determining potential equipment candidates. The formula combines various weighting factors, equipment use, and savings potential to produce a keep factor. Assets with low keep factors are selected first. Recommendations for further studies are also made. / http://archive.org/details/expansionofequip00obry / Captain, United States Marine Corps / Captain, United States Marine Corps
92

Effects of environment forcing on marine boundary layer cloud-drizzle processes

Wu, Peng, Dong, Xiquan, Xi, Baike, Liu, Yangang, Thieman, Mandana, Minnis, Patrick 27 April 2017 (has links)
Determining the factors affecting drizzle formation in marine boundary layer (MBL) clouds remains a challenge for both observation and modeling communities. To investigate the roles of vertical wind shear and buoyancy (static instability) in drizzle formation, ground-based observations from the Atmospheric Radiation Measurement Program at the Azores are analyzed for two types of conditions. The type I clouds should last for at least 5h and more than 90% time must be nondrizzling and then followed by at least 2h of drizzling periods, while the type II clouds are characterized by mesoscale convection cellular structures with drizzle occur every 2 to 4h. By analyzing the boundary layer wind profiles (direction and speed), it was found that either directional or speed shear is required to promote drizzle production in the type I clouds. Observations and a recent model study both suggest that vertical wind shear helps the production of turbulent kinetic energy (TKE), stimulates turbulence within cloud layer, and enhances drizzle formation near the cloud top. The type II clouds do not require strong wind shear to produce drizzle. The small values of lower tropospheric stability (LTS) and negative Richardson number (R-i) in the type II cases suggest that boundary layer instability plays an important role in TKE production and cloud-drizzle processes. By analyzing the relationships between LTS and wind shear for all cases and all time periods, a stronger connection was found between LTS and wind directional shear than that between LTS and wind speed shear.
93

Vliv stretchingu na maximální svalový výkon / Stretching and the Maximal Muscle Strength

Šádek, Petr January 2014 (has links)
Title: The effect of stretching on maximal muscle performance Objectives: Due to the number of studies, concerning the effect of the muscle stretch on sport performance and their heterogeneity in the term of used parameters, tests and even performing the stretch exercises themselves, it would be desirable, thanks to the importance of this subject, to consolide and evaluate up-to-date knowledge. The goal of this diploma thesis is to compare and assess available literature concerning the effect of muscle stretch during warmup on the sport performance and, ideally, to define the best type of the stretching itself. Method: The diploma thesis is composed as a literature review - an integrative review with exactly defined criteria for the use of available studies. Result : Even with the nonuniformity of parameters used in available studies there is a consensus in most of the used sources, which met the criteria of inclusion in this research, which (the consensus) determinates the dynamic stretching as the form most appropriate for enhancing the following sport performance. Although studies, proving this result, are in their findings quite unanimous, a precise definition of prefered exercises for peforming the dynamic stretching and of its parameters is still missing. Key words: stretching, dynamic,...
94

Dioïdes et idéaux de polynômes en analyse statique / Static analysis with dioids and polynomial ideals

Jobin, Arnaud 16 January 2012 (has links)
L'analyse statique a pour but de vérifier qu'un programme a le comportement souhaité c.à.d. satisfait des propriétés de sûreté. Toutefois, inférer les propriétés vérifiées par un programme est un problème difficile : le théorème de Rice énonce que toute propriété non triviale d'un langage de programmation Turing-complet est indécidable. Afin de contourner cette difficulté, les analyses statiques effectuent des approximations des comportements possibles du programme. La théorie de l'interprétation abstraite permet de donner un cadre formel à ces approximations. Cette théorie, introduite par Cousot & Cousot propose un cadre d'approximation basé sur la notion de treillis, de connexion de Galois et de calculs de points fixes par itération. Ce cadre permet de définir la qualité des approximations effectuées et notamment la notion de meilleure approximation. À l'opposé, les notions quantitatives n'apparaissent pas naturellement dans ce cadre. Nous nous sommes donc posés la question de l'inférence, par analyse statique, de propriétés s'exprimant de manière quantitative (telles que l'utilisation de la mémoire ou le temps d'exécution). / Static analysis aims to verify that programs behave correctly i.e. satisfy safety properties. However, generating properties verified by a program is a difficult problem : Rice’s theorem states that any non-trivial property about the language recognized by a Turing machine is undecidable. In order to avoid this difficulty, static analyses approximate the possible behaviours of the program. Abtract interpretation theory defines a formal framework for approximating programs. This theory, introduced by Cousot & Cousot is based on the mathematical structure of lattices, Galois connections and iterative fixpoints calculus. This framework defines the notion of correct approximation and allows for qualitatively compare approximations. On the contrary, it is not suitable for handling quantitative properties (such as memory usage and execution time).
95

A static scheduler for the computer aided prototyping system: an implementation guide

Janson, Dorothy M. 03 1900 (has links)
Approved for public release; distribution is unlimited / As demand for hard real-time and embedded computer systems increases, a new approach to software development is critical. Software engineers and users would benefit from an automated methodology allowing validation of design specifications or functional requirements early in the development life cycle. A fast, efficient, easy-to-use tool would increase productivity and would enhance user confidence that software would be delivered at less cost and on schedule. The Computer Aided Prototyping System (CAPS) is a conceptualized tool providing these capabilities. This thesis represents a pioneering effort to develop a Static Scheduler for the CAPS Execution Support System using the Ada programming language. The Static Scheduler initially extracts critical operators, timing constraints and precedence relationships from a high-level prototype source program. The Static Scheduler then creates a static schedule for run-time execution, using worst case scenarios, guaranteeing that timing constraints are met. The primary goal of this thesis is to provide the scheduling algorithms and implementation guidelines for the Static Scheduler. Secondary goals are to demonstrate the significance of continued research to telecommunications applications and to demonstrate the feasibility of Ada as the implementation language. / http://archive.org/details/staticschedulerf00jans / Lieutenant, United States Navy
96

First-Order Models for Configuration Analysis

Nelson, Tim 25 April 2013 (has links)
Our world teems with networked devices. Their configuration exerts an ever-expanding influence on our daily lives. Yet correctly configuring systems, networks, and access-control policies is notoriously difficult, even for trained professionals. Automated static analysis techniques provide a way to both verify a configuration's correctness and explore its implications. One such approach is scenario-finding: showing concrete scenarios that illustrate potential (mis-)behavior. Scenarios even have a benefit to users without technical expertise, as concrete examples can both trigger and improve users' intuition about their system. This thesis describes a concerted research effort toward improving scenario-finding tools for configuration analysis. We developed Margrave, a scenario-finding tool with special features designed for security policies and configurations. Margrave is not tied to any one specific policy language; rather, it provides an intermediate input language as expressive as first-order logic. This flexibility allows Margrave to reason about many different types of policy. We show Margrave in action on Cisco IOS, a common language for configuring firewalls, demonstrating that scenario-finding with Margrave is useful for debugging and validating real-world configurations. This thesis also presents a theorem showing that, for a restricted subclass of first-order logic, if a sentence is satisfiable then there must exist a satisfying scenario no larger than a computable bound. For such sentences scenario-finding is complete: one can be certain that no scenarios are missed by the analysis, provided that one checks up to the computed bound. We demonstrate that many common configurations fall into this subclass and give algorithmic tests for both sentence membership and counting. We have implemented both in Margrave. Aluminum is a tool that eliminates superfluous information in scenarios and allows users' goals to guide which scenarios are displayed. We quantitatively show that our methods of scenario-reduction and exploration are effective and quite efficient in practice. Our work on Aluminum is making its way into other scenario-finding tools. Finally, we describe FlowLog, a language for network programming that we created with analysis in mind. We show that FlowLog can express many common network programs, yet demonstrate that automated analysis and bug-finding for FlowLog are both feasible as well as complete.
97

Quasi-static Fracture Evolution with Cohesive Energy

Li, Yiqing 19 July 2016 (has links)
"The last fifteen years have seen much success in the analysis of quasi-static evolution for Griffith fracture, which is the mathematically natural starting point for studying fracture. At the same time, attempts have been made to show existence for similar models based on cohesive fracture rather than Griffith. These models are generally viewed as physically more realistic than Griffith, in that they are better models for crack nucleation. These attempts at existence proofs have been unsuccessful without very strong additional assumptions, for example, specifying the crack path a priori. The main purpose of this thesis is to characterize as well as possible the mathematical difficulties in cohesive fracture, and to make progress toward an existence result without the prescribed crack path assumption. So far, the most powerful method for existence proofs is to build a sequence of approximate solutions, based on time discretization, and take the limit as the time steps go to zero. We show that there are mainly two complications on the cracks of these approximate solutions that we need to rule out in order to show existence. The first one is due to the potential oscillation of the crack path. The second is due to the potential splitting of a crack into two or more nearby cracks, with the same total jump in displacement. We begin by first constructing an example illustrating how oscillations described above can affect the minimality of the limit. Then we prove that the splitting described above can be ruled out for any sequence of unilateral minimizers. With this result, we show how exactly oscillation affect the minimality on the limit of the sequence. We then move to the evolution problem and show the convergence of energy for almost every t. Based on this result we develop a method that allows us to analyze the problem using only a finite set of times. An application of this method is a proof of absolute continuity. Future work will be aimed at using the tools we developed to rule out oscillation and finally to prove existence results under more general assumptions."
98

Strides Towards Better Application Security

Balasubramanian, Sathyaraj 01 December 2008 (has links)
Static analysis tools analyze source code for vulnerabilities. However, these types of tools suffer from various problems that limit their effectiveness. This thesis examines these static analysis tools and suggests techniques for making them more efficient at detecting different types of vulnerabilities. The thesis further analyzes possible causes for these vulnerabilities by examining the source code written by programmers of various categories. Finally, this thesis discusses solutions and techniques to improve general security awareness as well as the importance of secure coding among the students and software developers.
99

Static Versus Dynamic Stretching Effect on Agility Performance

Troumbley, Patrick 01 May 2010 (has links)
The purpose of this study was to compare effects of static and dynamic stretching on explosive agility movements, and to examine the effect of the interaction of dynamic and static stretching prior to explosive agility movements. Fourteen men and 10 women performed the different warm-up protocols, including no warm-up (NWU), static stretching (SS), dynamic stretching (DS), and dynamic stretching with static stretching (DS+SS). The T-Drill was used to assess agility. The results indicated no difference between the NWU and SS conditions (effect size = 0.40, p = 0.06), as well as no significant difference between the NWU and DS+SS conditions (effect size = 0.01, p = 0.48), and the SS and DS+SS conditions (effect size = 0.40, p = 0.06). Statistically significant differences were found between the NWU and DS conditions (effect size = 0.45, p = 0.03), the SS and DS conditions (effect size = 0.85, p < 0.001), and the DS and DS+SS conditions (effect size = 0.40, p = 0.03). Agility test times, in order from fastest to slowest, were (a) dynamic stretching (10.87 ± 1.07 s), (b) dynamic stretching + static stretching (11.41 ± 1.26 s), (c) no warm-up (11.42 ± 1.21 s), (d) static stretching (11.90 ±1.35 s). Dynamic stretching resulted in the fastest agility test time. Static stretching resulted in the slowest agility times. The benefits of dynamic stretching may have been diluted when followed by Static Stretching, and the agility test time was the same as if no form of stretching was completed. Static stretching prior to agility is not recommended as it has a negative effect on the stretch shortening cycle, and agility. The results support the use of dynamic stretching prior to agility performance.
100

A Comparison of Resistance to Extinction Following Dynamic and Static Schedules of Reinforcement

Craig, Andrew R. 01 May 2013 (has links)
Resistance to extinction of single-schedule performance is negatively related to the reinforcer rate that an organism experienced in the pre-extinction context. This finding opposes the predications of behavioral momentum theory, which states that resistance to change, in general, is positively related to reinforcer rates. The quantitative model of extinction provided by behavioral momentum theory can describe resistance to extinction following single schedules in a post-hoc fashion, and only if the parameters of the model are allowed to vary considerably from those typically derived from multiple- schedule preparations. An application of the principles of Bayesian inference offers an alternative account of extinction performance following single schedules. According to the Bayesian change-detection algorithm, the temporal intervals of non-reinforcement that an organism experiences during extinction are compared to the temporal distribution of reinforcers that the organism experienced during baseline. A transition to extinction is more readily detectable when the previously collected distribution of reinforcers in timeis populated with relatively short intervals (i.e., when more frequent reinforcement was experienced during baseline). The Bayesian change-detection algorithm also suggests that changes in reinforcer rates are more detectable when organisms have temporally proximal experience with frequently changing rates. The current experiment investigated this novel prediction. Pigeons pecked keys for food under schedules of reinforcement that arranged either relatively dynamic reinforcer rates or relatively static rates across conditions. Following each period of reinforcement, resistance to extinction was assessed. Persistence was greater following static contingencies than following dynamic contingencies for the majority of subjects. These data provide support for the Bayesian approach to understanding operant extinction and might serve to extend behavioral momentum theory by offering change detection as an additional mechanism through which extinction occurs.

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