Submitted by Maria Aparecida (cidazen@gmail.com) on 2017-08-18T14:43:06Z No. of bitstreams: 1 Gilberto.pdf: 2769310 bytes, checksum: 210d2e0115f0c134b325cbf3a2354263 (MD5) / Made available in DSpace on 2017-08-18T14:43:06Z (GMT). No. of bitstreams: 1 Gilberto.pdf: 2769310 bytes, checksum: 210d2e0115f0c134b325cbf3a2354263 (MD5) Previous issue date: 2009-02-13 / CAPES / During the development of Grid middleware systems, researchers often employ simulation tools and techniques for validating new concepts and implementations. Simulation tools play a fundamental role on the development of Grid middleware systems since: (a) researchers often do not have access to huge Grid testbed environments, limiting the capacity for evaluating situations that demand high amount of resources; (b) it is difficult to explore in large scale application and resources scenarios involving several users in a repetitive and controlled way, due to the dynamic nature of Grid environments; (c) real Grid applications usually consume great amount of time, ranging from a few hours to even weeks. This work describes OGST, an object-oriented discrete event simulator whose main objective is to assist developers of opportunistic Grid middleware on validating new concepts and implementations. The preliminary motivation for OGST development was to provide a way for evaluating the behavior of scheduling algorithms commonly used on Grid environments under different execution environment conditions and the investigation of adaptive scheduling approaches. It was carefully designed to take into consideration the dynamics of opportunistic Grids, providing a set of features that hasten the development of simulations that takes into consideration the dynamism of the execution environment. The simulator was developed in the context of the InteGrade project, but was designed to allow the simulation of generic opportunistic Grids in order to be applied by other Grid middleware research projects. / Durante o desenvolvimento de sistemas de middleware de grade, pesquisadores freqüentemente empregam técnicas e ferramentas de simulação para valida- ção de novos conceitos e implementações. Ferramentas de simulação têm um papel fundamental no desenvolvimento de sistemas de middleware de grade uma vez que: (a) pesquisadores freqüentemente não têm acesso a grandes ambientes de grade para testes, limitando a capacidade para avaliar situações que demandam por uma grande quantidade de recursos; (b) é difícil explorar cenários com recursos e aplicações em larga escala envolvendo diversos usuários de forma repetitiva e controlada, devido à natureza dinâmica de ambientes de grade; (c) aplicações reais da grade geralmente consomem muito tempo, de poucas horas até mesmo a semanas. Este trabalho descreve o OGST, um simulador de eventos discretos orientado a objetos cujo principal objetivo é auxiliar desenvolvedores de sistemas de middleware de grade oportunista na validação de novos conceitos e implementações. A motivação preliminar para o desenvolvimento do OGST foi prover um caminho para avaliar o comportamento de algoritmos de escalonamento comumente usados em ambientes de grade sob diferentes condições do ambiente de execução e a investigação de abordagens de escalonamento adaptativo. Ele foi cuidadosamente projetado para levar em consideração a dinâmica de grades oportunistas, provendo um conjunto de funcionalidades que agilizam o desenvolvimento de simulações que consideram o dinamismo do ambiente de execução. O simulador foi desenvolvido no contexto do projeto InteGrade, mas foi projetado para permitir a simulação de grades oportunistas de uma maneira em geral com o propósito de ser aplicado a outros projetos de pesquisa envolvendo middleware de grades.

No description available.

This thesis had its inception in the mind of the writer when, disturbed by third grade children's lack of interest and low level of linguistic achievement, she endeavored to find both a more effective means of encouraging children to acquire the tools of language and a more effective method of teaching children the fundamentals of language arts. The writer determined, therefore, to investigate an integrated language arts program in the hope that it would prove to be a more effective method of teaching.

The primary purpose of this paper is to evaluate student and teaching faculty response to the formal procedures used at a large university to officially warn students who are in danger of failing, and to study the relationship of this process to such factors as college entrance examinations and subsequent grades.

FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / Information security in grid computing involves requirements that go beyond the traditional networks. Concerning specifically Integrity, most of existing solutions deal with it only during data transmission, ensuring non-violation of data in the communication between machines. Nevertheless, it is also necessary to guarantee data integrity during its processing, so that jobs results must not suffering any improper handling. Otherwise, the results manipulation compromises the application as a whole, also causing a high processing overhead. In order to avoid that grid users obtain uncorrected results due to malicious elements, this work proposes a diagnosis model for tolerating security faults in largescale computational grids, considering the integrity verification during job processing. In this way, it is possible to exclude those misbehaving processing units (nodes) interested in damaging the execution of processes, providing thus a high performance computing environment only formed by reliable nodes. The usage of system-level diagnosis as a strategy against jobs results manipulation attacks reveals itself an efficient solution, since it does not depend on the hardware platform and it is interoperable with security local solutions. This feature allows the employment of the proposed model at the majority of grid computing middlewares. Furthermore, the proposed diagnosis model organizes the nodes into logical clusters, establishing a hierarchy among them, in accordance to the role of each node (executor, tester or ultra-reliable), assigned through its historical behavior in the environment. This approach enables diagnosis to be made in a distributed way with the participation of nodes that provide an expected degree of confidence. To validate this strategy, a new security layer was implemented in a grid simulator in order to introduce the assertions and the behaviors described in the proposed model. The results testify the effectiveness of the model at scenarios with different quotas of malicious nodes, providing a rate of detection of 100% and accuracy of 99,7% of processed jobs, with 12,3% of overhead. / A seguranÃa da informaÃÃo em grades computacionais envolve requisitos que vÃo alÃm dos estabelecidos para as redes convencionais. Tratando-se especificamente de Integridade, a maioria das soluÃÃes existentes resolve essa questÃo apenas no escopo de transmissÃo, garantindo a nao-violaÃÃo dos dados durante a comunicaÃÃo entre as maquinas. Todavia, e preciso tambÃm garantir a integridade dos dados durante o seu processamento, de modo que os resultados das tarefas (jobs) processados em uma grade nÃo sofram qualquer alteraÃÃo indevida. De outra forma, a manipulaÃÃo de resultados compromete a aplicaÃÃo como um todo, incidindo num alto custo em termos de desempenho. Para evitar que usuÃrios obtenham resultados incorretos em virtude de elementos maliciosos, esta dissertaÃÃo propÃe um modelo de diagnostico para tolerÃncia a falhas de seguranÃa em grades computacionais de larga escala, abordando a verificaÃÃo de integridade na execuÃÃo dos jobs. Desta forma, e possÃvel excluir as unidades de processamento (nÃs) de mà conduta interessadas em comprometer as aplicaÃÃes, oferecendo, portanto, um ambiente de computaÃÃo de alto desempenho formado apenas por nos confiÃveis. A utilizaÃÃo de diagnostico em nÃvel de sistema como estratÃgia contra ataques de manipulaÃÃo de resultados de jobs mostra-se uma soluÃÃo eficaz, visto que independe das plataformas de hardware utilizadas e à interoperavel com soluÃÃes de seguranÃa locais, o que viabiliza seu emprego na maioria das middlewares de grades computacionais. AlÃm disso, o modelo de diagnostico aqui apresentado organiza os nÃs em clusters lÃgicos, estabelecendo assim uma hierarquia entre os mesmos, de acordo com o papel de cada nà (executor, testador ou ultra-confiÃvel), atribuÃdo segundo seu histÃrico comportamental no ambiente. Essa abordagem permite que o diagnÃstico seja feito de forma distribuÃda com a participaÃÃo dos nÃs que possuem um nÃvel mÃnimo de confiabilidade. Para validar esta estratÃgia, uma nova camada de seguranÃa foi implementada em um simulador de grades, a fim de introduzir as asserÃÃes e os comportamentos descritos no modelo proposto. Os resultados obtidos atestam a sua eficÃcia em cenÃrios com diferentes taxas de nÃs mal intencionados, oferecendo um Ãndice de detecÃÃo de 100% e acurÃcia de 99,7% dos jobs processados, com 12,3% de custo de processamento.

<p>The idea of the essay is to give a glimpse of the how the tranfunction of the ninth grade students’ grades in transition from high school to the gymnasium. The model used in the analysis is hermeneutic and this has permeated the paper strong. The issues I wanted the paper would answer was: What problems may exist in the assessment of pupils at the end of grade nine in Swedish and mathematics? How does this affect the transition between high school and the gymnasium? What individual differences can arise?</p><p>The problems surrounding the assessment of students in the ninth grade are not only the objectives of the different rates that affect the assessment. Students' relationship with teachers is an important factor that plays into how they are assessed. The high school teachers admit that students can get approved in Swedish A and Mathematics A, although they have not achieved all the objectives of the substances. Students cannot see any connection between this and the difficulties they have to cope with the courses in Swedish A and Mathematics A. Gymnasium teachers, however believe that this may be a factor that students do not reach the intended targets.</p><p>The analysis also shows that it is difficult for teachers to know what skills students bring to school. The two high school teachers think that the knowledge they assessed and rated is not necessarily the consolidation of the pupil. It is very possible that the knowledge which they exhibit is constant. The survey also shows how students can be affected both positively and negatively by the problems associated with a nicer grad than they diserve. The two student examples highlighted in this paper shows, for example, that students may have trouble keeping up with the teaching and understand what teachers go through this saw Simon as very tough. It can also give students the benefits when they get the chance to attend the gymnasium and continue their studies immediately after high school.</p>

Parental divorce is a stressful process that has been associated with long-term developmental implications for the children involved. There have been mixed results from research regarding specific effects of parents' marital status on levels of psychological distress and academic achievement in late adolescence and early adulthood. Research using a clinical sample from a college counseling center was lacking altogether. The primary goal of this study was to establish if there are relationships between parents' marital status, students'degree of psychological distress and academic achievement within a clinical sample of college undergraduates. The secondary goal was to determine if student gender interacts with parents' marital status on measures of psychological distress and academic achievement. Participants included 324 undergraduate college students aged 17-24 years who received clinical services at a student counseling center of a private university in a large metropolitan area in the Southeastern United States. Primary analyses found no statistically significant differences for self-reported GPA and therapists' perception of psychological distress by parents' marital status (married, divorced or divorced/remarried). In addition, it was found that gender did not have a statistically significant interaction with parents' marital status on psychological distress or academic achievement. Student's residential status was found to significantly covary with psychological distress, suggesting that students who lived off campus were perceived as being significantly more distressed than students who lived on campus, independent of parents' marital status. Results of this study have implications for college counseling center personnel to obtain a thorough family history at intake and monitor changes in residential status throughout the course of treatment. Results of this study also have implications for university administrators and student affairs personnel to include researching, planning and implementing interventions and programming for commuter students, and possibly expanding on-campus housing.

The idea of the essay is to give a glimpse of the how the tranfunction of the ninth grade students’ grades in transition from high school to the gymnasium. The model used in the analysis is hermeneutic and this has permeated the paper strong. The issues I wanted the paper would answer was: What problems may exist in the assessment of pupils at the end of grade nine in Swedish and mathematics? How does this affect the transition between high school and the gymnasium? What individual differences can arise? The problems surrounding the assessment of students in the ninth grade are not only the objectives of the different rates that affect the assessment. Students' relationship with teachers is an important factor that plays into how they are assessed. The high school teachers admit that students can get approved in Swedish A and Mathematics A, although they have not achieved all the objectives of the substances. Students cannot see any connection between this and the difficulties they have to cope with the courses in Swedish A and Mathematics A. Gymnasium teachers, however believe that this may be a factor that students do not reach the intended targets. The analysis also shows that it is difficult for teachers to know what skills students bring to school. The two high school teachers think that the knowledge they assessed and rated is not necessarily the consolidation of the pupil. It is very possible that the knowledge which they exhibit is constant. The survey also shows how students can be affected both positively and negatively by the problems associated with a nicer grad than they diserve. The two student examples highlighted in this paper shows, for example, that students may have trouble keeping up with the teaching and understand what teachers go through this saw Simon as very tough. It can also give students the benefits when they get the chance to attend the gymnasium and continue their studies immediately after high school.

The overall purpose of this concurrent mixed methods study was to develop an online performance assessment using content questions taken from a reputable seventh and eighth grade standardized assessment that effectively evaluated and allowed preservice middle grades mathematics teachers to demonstrate their mathematics knowledge for teaching in the four main content strands of algebra, probability and statistics, geometry, and number and operations. In addition, this study examined differences in mathematics knowledge for teaching in enrollment characteristics, in courses taken and currently taking, and in three different cohorts, each at different stages in the program, of 122 preservice middle grades mathematics teachers at a large public university in central Texas. Constant comparative analysis and descriptive statistics revealed average scores on the seventh and eighth grade content questions. The middle grades preservice teachers’ content understanding and pedagogical understanding responses indicated several misunderstandings and misinterpretations in the middle grades mathematics they were tested on. Content knowledge, content understanding, and pedagogical understanding together made up a preservice teacher’s mathematics knowledge for teaching. The study revealed that although preservice middle grades teachers could answer a content question correctly; they did not necessarily understand the process they used to arrive at their answer. In addition, their lack of explanation and knowledge of how to complete the problem correctly was transferred to their pedagogical understanding of the same problem. There was a general indication of increasing mathematics knowledge for teaching for each content strand across enrollment characteristics (freshmen, sophomore, etc.) and cohorts. However, there was a noticeable decrease in average mathematics knowledge for teaching scores during middle grades preservice teachers’ junior year. Special integrated mathematics and pedagogy courses (MASC) and the middle grades methods course had the greatest affect on preservice teachers’ mathematics knowledge for teaching each content strand scores. Recommendations are also included in the study which may be used to help shape reform initiatives in teacher education programs throughout the United States.

Teachers' construction of and motivation for using new mathematics knowledge learned in professional development differs from students' learning of mathematical concepts. However, teachers also vary in their use of new mathematics content in their own classrooms. This qualitative study followed teachers from a professional development course in algebra into their classrooms in order to investigate how teachers connect mathematics content from PD with the content they teach. The results of this study established three modes of connection (direct connection, indirect connection, and disconnection) and contextualized these connections by exploring teachers' motivations for participating in professional development and analyzing their alignment with the perspective on and development of the content taken by the PD course's instructors.