Radiation therapy has become a very import method for treating cancer patients. Thus, it is extremely important to accurately determine the location of energy deposition during these treatments, maximizing dose to the tumor region and minimizing it to healthy tissue. A Coarse-Mesh Transport Method (COMET) has been developed at the Georgia Institute of Technology in the Computational Reactor and Medical Physics Group for use very successfully with neutron transport to analyze whole-core criticality. COMET works by decomposing a large, heterogeneous system into a set of smaller fixed source problems. For each unique local problem that exists, a solution is obtained that we call a response function. These response functions are pre-computed and stored in a library for future use. The overall solution to the global problem can then be found by a linear superposition of these local problems. This method has now been extended to the transport of photons and electrons for use in medical physics problems to determine energy deposition from radiation therapy treatments. The main goal of this work was to develop benchmarks for testing in order to evaluate the COMET code to determine its strengths and weaknesses for these medical physics applications. For response function calculations, Legendre polynomial expansions are necessary for space, angle, polar angle, and azimuthal angle. An initial sensitivity study was done to determine the best orders for future testing. After the expansion orders were found, three simple benchmarks were tested: a water phantom, a simplified lung phantom, and a non-clinical slab phantom. Three more clinically relevant problems were developed from patient CT scans. Different coarse-mesh sizes and incident energies were tested. The COMET solutions for each case were compared to a reference solution obtained by pure Monte Carlo results from EGSnrc. In most cases, the COMET solutions produced reasonably good agreement with the COMET solutions. It was found that better results were obtained for lower energy incident photon beams as well as for larger mesh sizes. Recommendations were made for future development of COMET and the numerical benchmarks.

This thesis presents two essays on real earnings management and future performance. The first essay draws on empirical studies that examine the three types of real earnings management activities in the United Kingdom (UK) for firms that are more likely to manipulate their earnings to avoid missing earnings targets. These targets include the zero earnings, and last year’s earnings. Also drawing from empirical studies, the second essay investigates the impact of real earnings management on firms’ future operating performance in the UK. In the first essay, I examine earnings management through real activities manipulation by using a sample of UK firms over the period 2009-2013. According to the transaction cost theory and opportunistic perspective of earnings management, the results of the first essay reveal that managers in UK suspect firm-years that manage earnings upward utilise more real earnings management activities to achieve earnings benchmarks opportunistically. Specifically, I find that (1) firms which manage upward earnings have unusually low cash flows from operations by offering price discounts or/and more lenient credit terms to increase sales; (2) firms that manage upward earnings have unusually low discretionary expenditures by cutting/reducing expenditures spending to improve reported margin and (3) firms which manage upward earnings, incur unusually high production costs by producing more products to report lower costs of goods sold in order to achieve their targets. Further, I find evidence that UK firms’ meeting/beating earnings benchmarks around zero earnings and last year’s earnings engage in sales-based manipulation and reducing/cutting discretionary expenses simultaneously; they also engage in overproducing products and reducing discretionary expenses at the same time. Furthermore, I do not find, however, evidence that managers in UK firms are associated with high real earnings management through sales-based manipulation to meet/beat last year’s earnings. On the other hand, I find evidence that manager in UK firms engage in income-increasing earnings management through accounting choice (e.g., accrual-based earnings management) to meet an earnings target. Motivated by agency conflicts of real earnings management (e.g., opportunistic and signalling perspectives), the second essay investigates whether there is an association between UK firms that manipulate their business operations to meet earnings benchmarks (e.g., zero earnings, last year’s earnings) and subsequent operating performance. I implement Fama and MacBeth’s (1973) regression analysis to examine the effects of the magnitude of real earnings management on firms’ future performance. Empirical test results show that manipulation of operating activities such as sales, discretionary expenditures, and production costs to meet earnings benchmarks has a significant positive consequence for firms’ subsequent operating performance and signals firms’ good future performance. Further, I find evidence that firms that manipulate their operating activities in the absence of meeting/beating earnings benchmarks experience a decline in their subsequent operating performance. The findings of this research lend support to our understanding of the process that management follows to evaluate costs and benefits of real earnings management.

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Com o aumento crescente das capacidades dos circuitos integrado e conseqüente complexidade das aplicações, em especial as embarcadas, um requisito tem se tornado fundamental no desenvolvimento desses sistemas: ferramentas de desenvolvimento cada vez mais acessíveis aos engenheiros, permitindo, por exemplo, que um programa escrito em linguagem C possa ser convertido diretamente em hardware. Os FPGAs (Field Programmable Gate Array), elemento fundamental na caracterização de computação reconfigurável, é um exemplo desse crescimento, tanto em capacidade do CI como disponibilidade de ferramentas. Esse projeto teve como objetivos: estudar algumas ferramentas de conversão C, C++ ou Java para hardware reconfigurável; estudar benchmarks a serem executadas nessas ferramentas para obter desempenho das mesmas, e ter o domínio dos conceitos na conversão de linguagens de alto nível para hardware reconfigurável. A plataforma utilizada no projeto foi a da empresa Xilinx XUP V2P / With the growing capacities of Integrated Circuits (IC) and the complexity of the applications, especially in embedded systems, there are now requisites for developing tools that convert algorithms C direct into the hardware. As a fundamental element to characterize Reconfigurable Computing, FPGA (Field Programmable Gate Array) is an example of those CIs, as well as the tools that have been developed. In this project we present different tools to convert C into the hardware. We also present benchmarks to be executed on those tools for performance analysis. Finally we conclude the project presenting results relating the experience to implement C direct into the hardware. The Xilinx XUP V2P platform was used in the project

Made available in DSpace on 2014-06-12T15:55:45Z (GMT). No. of bitstreams: 2 arquivo2286_1.pdf: 1818614 bytes, checksum: bde38ef39500718996aa2511dab57905 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2008 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Apesar de sistemas multiagentes estarem se tornando cada vez mais comuns no desenvolvimento de software, há ainda que se chegar a um consenso sobre como modelar e comparar diferentes soluções de sistemas multiagentes para um mesmo problema. Em outras palavras, os pesquisadores de tal área ainda estão à procura de benchmarks que sirvam de referência para a comparação de abordagens distintas. Dada a importância do estabelecimento de benchmarks para sistemas multiagentes, uma questão que surge entre os pesquisadores da área de patrulhamento é a possibilidade e o potencial do problema do patrulhamento como um destes benchmarks. Apesar da quantidade de trabalho produzido até este ponto, tem-se encontrado dificuldades para comparar precisamente as soluções propostas para o patrulhamento. Estas dificuldades remetem principalmente à ausência de ferramentas (em especial um simulador unificado) que permitam aos estudiosos se concentrarem na solução do problema em si, e não na sua representação. Partindo deste cenário, este trabalho tem como objetivo discutir o estabelecimento do patrulhamento enquanto um benchmark para sistemas multiagentes. Adicionalmente, como um primeiro passo no sentido de preencher as lacunas que dificultam tal estabelecimento, introduz-se o SimPatrol, um novo simulador voltado para a tarefa de patrulhamento, fortemente inspirado pelos simuladores da RoboCup e TAC. Novos resultados são produzidos a partir de uma avaliação de parte das técnicas propostas pelas pesquisas anteriores frente às novas funcionalidades implementadas pelo simulador, em especial a inédita medida de ociosidade dos vértices, que leva em consideração o tempo de raciocínio gasto pelos patrulheiros

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The purposes for this study were: (a) to establish benchmark metrics for selected variables related to characteristics of physical therapy education programs; and (b) to determine how well a subset of the variables predicted group membership based on first-time pass rates (FTPRs) on the National Physical Therapy Examination (NPTE). The population was defined as all physical therapy programs in the United States and Puerto Rico accredited by the Commission on Accreditation in Physical Therapy Education. Questionnaires soliciting data related to the variables were mailed to the entire population (N = 177). Fifty-eight (32.8%) of the programs returned the questionnaire, with 51 (29%) having provided enough information for inclusion in the study. Characteristics of the sample were compared to known population characteristics in order to determine the extent to which the sample represented the population. Pearson product-moment correlation resulted in a coefficient of .993, indicating that the two groups were similar. Descriptive statistics were calculated. Values for the variables were tabulated in various ways, based on the nature of sponsoring institution, regional location, degree offered, and grouping based on FTPRs, in order to facilitate comparisons. A single institution was selected and comparisons made to demonstrate the utilization of benchmark metrics. Chi-squared tests were conducted to study the relationship between curriculum model, degree offered, and grouping. The resulting values of c 2 indicated that these variables were independent of each other. Classification accuracy was determined through discriminant analysis. Results indicated 80% accuracy for this sample; however, the accuracy was only 47% on cross-validation. Structure coefficients were calculated to determine the relative contribution of each variable to the prediction. The findings demonstrate the usefulness of benchmark metrics for facilitating quality improvement in physical therapy education programs. There is, however, need for improvement in the process, and further research should be conducted to develop a realistic model for predicting group membership based on FTPRs.

As current educational policies continue to emphasize the importance of college readiness and growth, it is essential to understand the degree to which test scores collected throughout middle school and high school can provide information to make valid inferences about students' college readiness. This thesis sought to summarize the college readiness of Iowa students, describe the nature of student growth, and clarify the relationship between student growth and college readiness. Together, the results support the validity argument that scores from a general achievement test can be used for measuring student growth and making on-track interpretations about college readiness. Results of analyses on the use of benchmarks as indicators of college readiness are presented first. The analyses showed that the state's general achievement test was just as accurate as the ACT when the criterion was defined by grades in domain-specific, credit-bearing courses. Next, latent growth models and growth mixture models were used to summarize and evaluate longitudinal changes in student achievement and their relationship with college outcomes. A calibration sample representing potential college-bound students was used to set the growth trajectories. Then a cohort of students representing the full student population was used to provide validity evidence in support of the growth trajectories. It was shown that students in the highest-performing group could be considered college ready. Several applications of the growth models are also presented. The typical performance on a variety of college outcomes for each developmental group was presented for the validation sample. A second application illustrated how individual patterns of growth in Grade 8 could be used to predict future class membership in Grade 11. This thesis was predicated on the notion that understanding and documenting the nature of student growth, the college readiness of Iowa students, and the relationship between the two is an important step in improving the college readiness of Iowa students and meeting the future needs of an aligned K-16 educational system. As this study is among the first to examine the relationship between college readiness and student growth using modern latent variable modeling techniques with actual college outcomes, guidelines for future research are presented.

<p>I start with a sample of 26,998 CEOs from the Compustat Executive Compensation (ExecuComp) database starting January 1, 1991 and ending January 1, 2009. I then match the sample with the FAA’s Airmen Certification database using the CEO’s first name, middle initial, and last name. Names with a match are coded as pilots and names without a match are coded as non-pilots. Following Roychowdhury (2006) I remove all firms in regulated industries (SIC codes between 4400 and 5000) as well as banks and financial institutions (SIC codes between 6000 and 6500). The resulting sample consists of 255 pilot-CEOs and 3,935 non-pilot-CEOs. I then merge the CEO dataset to the Compustat Fundamentals Annual database to obtain a final sample consisting of 1,038 CEO-pilot firm-years and 18,455 CEO-non-pilot firm-years. All variables are winsorized at the 1% and 99% levels.</p><p><a></a> </p><div><br><div><p><br></p></div></div>

In recent years interest in L2 reading research has focused largely on word frequency, sentence level, word recognition, and several researchers have begun to use eye tracking to better study reading behaviors. Parshina et al. (under review) have found that high proficiency heritage speakers of Russian read faster in terms of gaze duration and total time and had fewer regressions than low proficiency heritage speakers. The current study focuses on the establishment of benchmarks for L2 Russian readers in terms of first fixation duration, gaze duration, and total time when reading a complete passage, and compares these variables among different proficiency levels. Thirty-two students participated in the study with proficiency levels ranging from Novice to Superior. Subjects completed eye tracking and reading comprehension passages with the use on an eye tracker to asses reading abilities. Results show that all participants read L1 significantly faster than L2 in terms of first fixation duration. Additionally, all proficiency levels read Intermediate passages faster than Advanced passages. These results help establish the first benchmarks for eye tracking in Russian as an L2.