Esta dissertação tem por objetivo apresentar a proposta de uma política de escalonamento para grids computacionais. Essa política, intitulada Dynamic Max-Min2x, é orientada ao escalonamento de aplicações cujas tarefas não realizam comunicação entre si e visa a redução do tempo de resposta dessas aplicações através da utilização de atribuição dinâmica de tarefas e replicação das mesmas. Experimentos, feitos através de simulação, mostram que o tempo médio de resposta de aplicações utilizando-se a Dynamic Max-Min2x é inferior ao de outras políticas da literatura. Análises dos resultados desses experimentos apontam que esse tempo tende a ser mais atrativo principalmente quando as tarefas necessitam de muito processamento e quando há grande variação de carga no sistema, caracteristicas comuns em grids computacionais. Além disso, esta dissertação apresenta a implementação de um framework utilizando-se o Globus Toolkit, onde é possível a inserção de políticas de escalonamento para a submissão inteligente de tarefas em um grid computacional. / This Master thesis proposes a new grid scheduling policy called Dynamic Max-Min2x. This policy focuses on applications in which tasks do not communicate among themsenves and targets a response time reduction of these applications through the use of dynamic task distribution and replication techniques. Experiments, done using simulations, have shown that the response time related to Dynamic Max-Min2x is smaller than others policies found in literature. Analysis of the results have demonstrated that this time tends to become more attractive when tasks do not need much processing power and when there is a great load variation in the system, characteristics frequently found in grids. Furthermore, this thesis presents the implementation of a framework using Globus Toolkit, which makes possible the new scheduling policies insertion to provide an intelligent submission tasks in a computational grid system.

京都大学 / 新制・課程博士 / 博士(教育学) / 甲第24988号 / 教博第297号 / 新制||教||221(附属図書館) / 京都大学大学院教育学研究科教育学環専攻 / (主査)教授 齊藤 智, 教授 MANALO Emmanuel, 准教授 高橋 雄介 / 学位規則第4条第1項該当 / Doctor of Philosophy (Education) / Kyoto University / DGAM

The use of still images in instruction has a long history in the field of education. With the widespread use of microcomputers and the development of graphic software, the ability to create and use animated images has greatly increased; today many people use animated images in their teaching and training activities. Since the use of different types of images in instruction has various influences on students'learning results, the different effects between animated images and still images have been studied widely among researchers. However, the research results are not consistent. Some research results show that animated images are more effective than still images and some show no difference or less effective results. This experimental study explores the effects of animated images and still images on college students' learning of motion-related tasks and non-motion related tasks, with the students possessing different levels of field dependence-independence. This study found that: For learning tasks involving motion and/or change, animated images were more effective than still images for college students, and field dependent students benefited more from animated images than did the field independent students. However, for learning tasks that did not involve motion or change, there was no difference in learning results from the use of still images as opposed to animated images. In addition, for such learning tasks, there was no difference in the learning benefits of still images to field dependent versus field independent learners. / Ph. D.

This thesis discusses any potentialities and usage of nonverbal tasks for teaching Physics. It primarily analyses the general physical tasks and their position in teaching Physics and then nonverbal physical tasks and their application. For nonverbal tasks there is an emphasis not only on the solutions, but also on the aspects of creativity and on the advancement of divergent thinking of students. The thesis contains a set of created nonverbal tasks and their solutions. Some of tasks are processed to the worksheets and these worksheets were used for experimental verification of tasks. The experimental results are connected with this thesis and analyzed there. The aim of experiments is verification of ability of pupils to solve nonverbal tasks and their ability to identify dependencies between conventional approaches and nonverbal approaches.

As life expectancy increases in modern societies, a greater importance has recently started to be given to cognitive aging. Alzheimer's disease (AD) affects the memory capability of individuals at advanced ages, independently of their general physical health. However, AD is suggested to have an undetectable development many years prior the first clear behavioral symptoms. This silent presence of AD may allow scientists to detect its initial stages, at which a combination of prevention treatments, such as medication and cognitive training, can be more effective. This study extends a line of research that aims to identify possible 'silent' biomarkers of AD using working memory performance and electrophysiological recordings (EEG) in healthy adults. Working memory (aka., short-term memory) is a memory sub-type used in everyday life that allows us to execute tasks in short periods of time. Given the significant parallels of working memory with other forms of long-term memory and its clear facility to be employed in experimental settings of short duration, working memory is a suitable candidate to identify early biomarkers of memory deficits ingeneral. In this study we assessed the cognitive performance and the electrophysiological response - via EEG signals - in a visual working memory recognition task that included the interference of past memories over the present ones. This 'proactive interference' effect is evaluated has a possible biomarker candidate for AD. Our findings reveal that subjects take longer reaction times in the recognition of visual items in the proactive interference condition in comparison to no interference. Additionally, we report an early (170-180 ms) and a later (430-450 ms) EEG components (ERP) that underlies the neural processing responsible for the resolution of this working memory interference. These two time intervals are interpreted as revealing the resolution of proactive interference at two difference stages of visual information processing ('letters'): the phonological (sub-lexical) and semantic (lexical) levels respectively. / --

Psychopathy is associated with several behavioral and psychophysiological deficits. Lynam (2002) has argued that the use of an overarching conceptualization of psychopathy can provide a parsimonious explanation of psychopathic pathology. The current study examined relations between tasks used to explore psychopathic pathology and dimensions from the Five Factor Model of personality. Undergraduate participants completed the NEO PI-R, the BART, a go/no-go task, an emotional morph task, and provided physiological responses to stimuli. While hypothesized relations to FFM psychopathy composites were generally unsupported, other interesting relations to traits were identified. Results indicated that hypoarousal to negative stimuli was negatively related to pan-impulsivity. Maladaptive risk taking was positively related to panimpulsivity and high self-directed negative affect. Response modulation deficits were negatively related to pan-impulsivity, low self-directed negative affect, and facets of openness. Deficits in empathic responding were positively related to other-directed negative affect and self-directed negative affect, and negatively related to pan-impulsivity and interpersonal assertiveness. Although it remains unclear whether the failure to support hypotheses was related to the study variables or population, results indicate that the FFM can provide additional information with regard to what deficit tasks assess.

The purpose of this study is to examine how respiratory sinus arrhythmia (RSA) is affected across paced breathing, attention, inhibition, and emotion-eliciting tasks and how those relationships may be mediated by emotion regulation strategies in children with different levels of externalizing and internalizing behaviors between the ages of 8 and 12 years. The first aim was to determine whether externalizing and internalizing symptoms during a paced breathing or natural breathing task better predicted RSA levels. The hypothesis was that internalizing and externalizing behaviors would be more predictive of RSA baseline levels when utilizing a paced-breathing method of measuring RSA. The second aim was to determine how RSA levels across an attention, inhibition, sad, and anger task are predicted by internalizing and externalizing symptoms after controlling for baseline RSA levels. There were four hypotheses: (1) as levels of externalizing behaviors increase, levels of baseline RSA would decrease, (2) as levels of internalizing behaviors increase, levels of baseline RSA will decrease, (3) there will be significantly smaller changes in RSA reactivity) as the level of externalizing behaviors increases, and (4) as levels of internalizing symptoms increase, there will be significantly larger changes in RSA levels relative to RSA baseline levels (RSA reactivity).The results showed that externalizing and internalizing behaviors did not predict RSA levels during a paced or natural breathing task. Additionally, there was very little difference in the outcomes when used either a natural or paced breathing method of RSA as a control variable except when predicting RSA levels during a sad emotion-eliciting task. Although RSA levels during three experimental tasks (attention, inhibition, and sad) were not significant, there were moderate effect sizes for externalizing and/or internalizing symptoms predicting various RSA reactivity (i.e., RSA levels after controlling for baseline) across these conditions. One model was significant in predicting the level of variance of RSA reactivity during an anger emotion-eliciting task, with internalizing and hyperactivity/inattention symptoms contributing the most variation in the model. Findings point towards understanding how internalizing and externalizing symptoms may impact an individual's physiological response during a task.

Increasingly, workplace information seeking takes place in digital information environments and is reliant upon search systems. Existing systems are designed to retrieve information that is relevant to the query, but are not capable of identifying information that is well-suited to the context and situation of a search. This is a problem for professionals who often are searching for a small amount of useful information that can be applied to a problem or task, and have limited time to browse through large sets of results. This inability of search systems to discriminate between relevant and useful documents is one of the core problems in information retrieval. In this dissertation, I address this problem by studying the role that contextual factors play in determining how a group of professionals searches for and selects information. The central question concerns the nature of the relationships between these contextual factors, specifically between the genres in the document collection and the tasks of the searcher, with an aim to exploit such relationships to improve workplace information retrieval. Research was conducted through multiple studies in three phases, moving from an exploratory study of workplace information behaviour to a controlled experimental user study. Findings confirm that workplace context shapes search behaviour. This relationship is modeled as a set of key contextual factors and sets of context-dependent access constraints, preferred document characteristics, and search strategies. Among the contextual factors identified, work tasks and information tasks were found to be significantly associated with document genres. This task-genre relationship was modeled as a matrix of associations between domain-specific task and genre taxonomies and successfully implemented as a filtering component in a workplace search system. This is the first major study of the relationship between task and genre in information seeking and of its application to information retrieval systems.

Approved for public release; distribution is unlimited / The role of the contracting officer has evolved through our nation's history from one of simply an intermediary between supplier and consumer to that of a sophisticated manager of requirements and resources. In the execution of his many and varied duties and responsibilities, the present-day contracting officer must interact with a variety of individuals and organizations. This report attempts to identify these various relationships, to analyze their characteristics, and to determine how each affects the contracting officer' s accomplishment of his primary tasks and responsibilities. The researcher proposes a model of the contracting officer's environment and identifies ten relationships involving the contracting officer which appear to predominate in this environment. The 169 procurement tasks compiled by Fowler from previous research are analyzed in the context of these relationships . The researcher concludes by revising the proposed model and suggesting that it be further refined by subsequent field validation. / http://archive.org/details/characteristicse00lawl / Captain, United States Army

The problem of this study is to demonstrate a method of evaluating situations in textual materials that may assist pre-adolescent children in achieving certain developmental tasks. The problem involves the analysis of fifty stories taken from five state-adopted readers on the sixth-grade level, as well as the development of criteria for making such an analysis.