731 |
Address Space Translation for FPGA Accelerated SimulatorsChamberlain, Michael Thaddeus 01 June 2015 (has links) (PDF)
Microarchitectural simulation is needed to help explore the large design space of new computer systems. These simulations are taking increasingly longer amounts of time to run due to the increasing complexity of modern processors. Co-simulation and high level synthesis are promising fields to improve the overall time required for microarchitectural simulators, and can contribute to low design times and fast simulation speeds permitting a larger range of design space exploration. While promising, co-simulation techniques must find effective ways to map the host memory address space to the FPGA memory address space to be able to correctly transfer simulation data between the host and FPGA. Load relations mapping is a new technique that builds upon existing techniques to provide support for the discovery and translation of runtime memory addresses to their equivalent FPGA memory addresses. This is accomplished by storing object reachability information discovered during a memory profiling run and later using it to recreate an object reachability mapping at runtime. This mapping can be traversed to discover needed memory addresses. We demonstrate how this technique can be used by incorporating it into the FAMEbuilder tool flow. Results show that simulation speed is not reduced and that only a small overhead is required to perform the additional memory initialization at the start of simulation. Area increases are also shown and are limited to near 10\% increase on small single core models.
|
732 |
The Effect of Load Carriage on the Biomechanics of Walking Gait: A Comparative Analysis of Male and Female SoldiersParrett, Matthew D. 05 May 2023 (has links)
No description available.
|
733 |
[en] ANALYSIS OF THE BEHAVIOR OF INTERCONNECT POWER SYSTEMS UNDER DISTURBANCES THAT AFFECT THE GENERATION AND LOAD BALANCE / [pt] ANÁLISE DO COMPORTAMENTO DE SISTEMAS ELETRÔNICOS INTERLIGADOS DURANTE DISTÚRBIOS QUE AFETAM O EQUILÍBRIO ENTRE CARGA E GERAÇÃOHEINRICH PARFIJANOWITSCH 14 September 2009 (has links)
[pt] Análise do comportamento de sistemas elétricos interligados durante distúrbios que afetam o equilíbrio entre carga e geração
Nos anos recentes ocorreram numerosos distúrbios em sistemas elétricos, resultando em serias interrupções do suprimento aos consumidores.
Embora as causas iniciais fossem as mais diversas, em muitos casos ocorreu perda de linhas de interligação importantes, produzindo forte sobrecarga numa parte do sistema. As oscilações de potência e a queda de freqüência resultante da sobrecarga, causaram um fracionamento ainda maior do sistema e desligamento em cascata das unidades geradoras na área ilhada.
Uma maneira de manter a integridade de um sistema com excesso de carga sobre a geração é pela aplicação de um esquema de rejeição automática de carga. Tais esquemas, utilizando modernos relés estáticos, permitem restabelecer eficientemente o equilíbrio carga-geração, evitando o colapso total, conservando a maior parte da carga e facilitando um rápido restabelecimento das condições normais.
Por este motivo os esquemas de rejeição automática de carga tem sido chamados também de Esquemas de conservação de carga.
A aplicação correta de um esquema automático de conservação de carga deve ser precedida de um estudo detalhado do sistema, levando em conta as características dinâmicas da geração e da carga.
Em sistemas de grande porte, o número e a complexidade dos fatores envolvidos tornam necessária a simulação digital.
Este trabalho analisa o comportamento de sistemas elétricos em condições de desequilíbrio e apresenta dois programas digitais para simulação dinâmica de sistemas elétricos, com ênfase especial na representação de esquemas automáticos de conservação de carga. / [en] In recent years there have been nemerous power system disturbances resulting in serious load interruptions. Although there were several causes, in many cases overload in part of the system. The ensuing power swings and frequency decay caused further loss of transmission lines and generating units, leading to a complete system shutdown.
One approach to the problem of maintaining the integrity of a power system with an excess of load over available generation is the application of an automatic load shedding program.
Automatic load shedding, with new static under frequency relays, can effectively restore load/generation balance, conserve a major portion of sytem load and facilitate rapid restoration of the system to normal.
For this reason the load shedding programs have also been called Load conservation programs.
The proper application of an automatic load conservation program should be preceded by an exrensive study of the system, considering the dynamic characteristics of the generation and load.
The complexity of large systems makes it necessary to use digital computer simulation.
This paper analyses the bahavior of power systems under unbalaced conditions and describes two digital computer programs suitable for the dynamic simulation of power systems, with special emphasis on the representation of automatic load conservation programs.
|
734 |
The Universal Design Paradigm: An Examination of Real-Time, C-Print, Meaning-for-Meaning Transcription and Individual Differences in LearningBoone, Amanda 01 May 2014 (has links)
The intent of this thesis is to guide further research and discussion of C-Print, meaning-for-meaning transcription and its applications to today’s dynamic classroom settings under a Universal Design Paradigm. Evidence suggests that providing these captions can benefit Deaf and Hard of Hearing populations and also that concise, textual representations of information increase retention for average learners in multimedia settings. Individual differences were considered and low internal control participants did significantly better on exams when material was captioned compared to when it was not. They also tended to outperform high internal control participants on captioned material exams.
|
735 |
Investigating The Effectiveness Of Redundant Text And Animation In Multimedia Learning EnvironmentsChu, Shiau-Lung 01 January 2006 (has links)
In multimedia learning environments, research suggests that simultaneous presentation of redundant text (i.e. identical narration and on-screen text) may inhibit learning when presented with animation at the same time. However, related studies are limited to testing with cause-and-effects content information (e.g., Moreno & Mayer, 1999, 2002). This study examined the effects of redundant text on learners' memory achievement and problem solving ability. The study replicated and extended prior research by using descriptive, rather than cause-and-effect content information. The primary research questions were (a) does redundant text improve learning performance if learners are presented with instructional material that addresses subject matter other than cause-and-effect relationship? and (b) does sequential presentation of animation followed by redundant text help learning? To answer the research questions, five hypotheses were tested with a sample of 224 Taiwanese students enrolled in a college level Management Information System (MIS) courses at a management college in southern Taiwan. Statistically significant differences were found in memory achievement and problem solving test scores between simultaneous and sequential groups; while no statistically significant differences were found in memory achievement and problem solving test scores between verbal redundant and non-redundant groups. These results were supported by interviewees expressing difficulty in connecting animation and verbal explanation in the two sequential presentation groups. The interview responses also helped to explain why insignificant results were obtained when redundant and non-redundant verbal explanations with animation were presented simultaneously. In general, the results support previous research on the contiguity principle, suggesting that sequential presentations may lead to lower learning performance when animation and verbal explanation are closely related. The separation of the two types of information may increase cognitive load. In addition, the study found that impairment of redundant text was also affected by various learning characteristics, such as the structure of the instructional content and learners previous learning experiences. Recommendations for future study include: (a) research on various situations such as characteristics of the content, characteristics of learners, and difficulty of the instructional material that influences the effects of redundant text, and (b) research on prior learning experience that influences the effects of simultaneous redundant text presentations.
|
736 |
Immediate Versus Delayed Feedback In Simulation Based Training: Matching Feedback Delivery Timing To The Cognitive Demands Of ThBolton, Amy 01 January 2006 (has links)
Optimal delivery of instruction is both critical and challenging in dynamic, scenario-based training (SBT) computer simulations such as those used by the military. Tasks that human instructors must perform during these sorts of simulated training exercises can impose a heavy burden on them. Partially due to advances in the state-of-the-art in training technology and partially due to the military's desire to reduce the number of personnel required, it may be possible to support functions that overburdened instructors perform by automating much of the SBT process in a computer simulation. Unfortunately though, after more than 50 years of literature documenting research conducted in the area of training interventions, few empirically-supported guidelines have emerged to direct the choice and implementation of effective, automated training interventions. The current study sought to provide empirical guidance for the optimal timing of feedback delivery (i.e., immediate vs. delayed) in a dynamic, SBT computer simulation. The premise of the investigation was that the demand for overall cognitive resources during the training exercise would prescribe the proper timing of feedback delivery. To test the hypotheses, 120 volunteers were randomly assigned to 10 experimental conditions. After familiarization on the experimental testbed, participants completed a total of seven, 10-minute scenarios, which were divided across two training phases. During each training phase participants would receive either immediate or delayed feedback and would perform either high or low cognitive load scenarios. Four subtask measures were recorded during test scenarios as well as subjective reports of mental demand, temporal demand and frustration. Instructional efficiency ratios were computed using both objective performance data and subjective reports of mental demand. A series of planned comparisons were conducted to investigate the training effectiveness of differing scenario cognitive loads (low vs. high), timing of feedback delivery (immediate vs. delayed), and sequencing the timing of feedback delivery and the cognitive load of the scenario. In fact, the data did not support the hypotheses. Therefore, post hoc, exploratory data analyses were performed to determine if there were trends in the data that would inform future investigations. The results for these analyses are discussed with suggested directions for future research.
|
737 |
Grid-Scale Energy Storage: A Proposed Control Algorithm for Sodium Sulfur BatteriesSpaizman, Daniel 01 July 2014 (has links) (PDF)
With carbon dioxide levels in our atmosphere reaching record highs and 2020 quickly approaching, California is expected to pave the way for the United States in terms of replacing fossil fuel generation facilities with various renewable energy power plants. It is well documented that the inherent variability and limited duty cycle of renewables has hindered their growth. Energy storage technologies represent the bridge that can help us cross the divide from where we stand to where we must stand in the next 6 years. Utility companies value services such as peak shaving, voltage support, and frequency regulation, all of which energy storage technologies can provide. Commercial and residential clients’ of the utility will begin to install their own storage systems once properly incentivized. In this paper, a control algorithm for Sodium Sulfur batteries is proposed with hopes that the aforementioned services will be provided to the utilities while system owners realize profit.
|
738 |
HTTP 1.2: Distributed HTTP for Load Balancing Server SystemsO'Daniel, Graham M 01 June 2010 (has links) (PDF)
Content hosted on the Internet must appear robust and reliable to clients relying on such content. As more clients come to rely on content from a source, that source can be subjected to high levels of load. There are a number of solutions, collectively called load balancers, which try to solve the load problem through various means. All of these solutions are workarounds for dealing with problems inherent in the medium by which content is served thereby limiting their effectiveness. HTTP, or Hypertext Transport Protocol, is the dominant mechanism behind hosting content on the Internet through websites. The entirety of the Internet has changed drastically over its history, with the invention of new protocols, distribution methods, and technological improvements. However, HTTP has undergone only three versions since its inception in 1991, and all three versions serve content as a text stream that cannot be interrupted to allow for load balancing decisions. We propose a solution that takes existing portions of HTTP, augments them, and includes some new features in order to increase usability and management of serving content over the Internet by allowing redirection of content in-stream. This in-stream redirection introduces a new step into the client-server connection where servers can make decisions while continuing to serve content to the client. Load balancing methods can then use the new version of HTTP to make better decisions when applied to multi-server systems making load balancing more robust, with more control over the client-server interaction.
|
739 |
Sexual Orientation Differences in the Association between Physical Activity and Allostatic Load: Results from the National Health And Nutrition Examination StudyPutnam, Natalia I 09 August 2023 (has links) (PDF)
Higher levels of allostatic load (AL), a composite measure of the impact of chronic stress on the body, are found among socially marginalized groups compared to privileged groups. AL is associated with premature aging and death, as well as a variety of chronic health conditions that impact quality of life. Effects of AL may be offset by physical activity (PA). Queer populations (including those who identify as lesbian, gay, or bisexual) may be at risk for elevated AL due to repeated exposure to discrimination in the form of sexual minority stress. There is mixed literature on sexual orientation differences in PA and research on AL among queer populations is limited. This study describes sexual orientation differences in the 1) prevalence of PA and mean AL levels and 2) association between PA and AL. Data from the 2001-2015 National Health and Nutrition Examination Survey were used to fit sex-stratified linear regression models assessing sexual orientation (heterosexual, gay/lesbian, bisexual, and heterosexual with same-sex experience) differences as well as sexual orientation-specific associations in PA and AL. AL was assessed using 8 biomarkers, while PA was assessed using metabolic equivalent of task (MET)-hours/week calculated from the Global Physical Activity Questionnaire. Models were adjusted for race/ethnicity, income, education, relationship status, veteran status, and citizenship status. Overall, heterosexual adults reported more PA than their same-sex queer counterparts. Gay men had lower (0.8), while bisexual men had higher AL scores (1.9) than heterosexual men (1.2). Among women, AL score was similar across sexual orientation groups. Overall, more PA was associated with lower AL scores among men and women (badjusted = -0.00508, padjusted=-0.00505, punadjusted =-0.00934, punadjusted =-0.03269, p=0.04), and heterosexual women with same-sex experience (bunadjusted =-0.01059, p=0.02). After adjusting for covariates the association was no longer statistically significant. Consistent with previous work, PA was inversely associated with AL score. PA may be an important modifiable behavior to mitigate some sexual orientation disparities in health.
|
740 |
Strategic placement of distribution network operator owned wind turbines by using market-based optimal power flowMokryani, Geev, Siano, P. January 2014 (has links)
No / In this study, a new methodology to optimally allocate wind turbines (WTs) in distribution networks is proposed. A market-based optimal power flow is used to determine the optimal numbers and capacities of WTs in a way that maximises the social welfare. The method is conceived for distribution network operators to strategically allocate WTs in distribution networks. The proposed method by yielding location-specific WTs capacity settlement both in terms of cost reduction and consumers' benefits is consistent with distribution network topology and constraints. The method is solved by using step-controlled primal dual interior point method considering network constraints. The effectiveness of the proposed method is demonstrated with two radial distribution systems including an 84-bus 11.4 kV and a 69-bus 11 kV network.
|
Page generated in 0.0498 seconds