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Análise de políticas públicas para educação superior no Brasil: uma aplicação de dinâmica de sistemas / Public policy analysis for higher education in Brazil: a systems dynamics applicationLuis Fernando Britto Pereira de Mello Barreto 26 April 2017 (has links)
Este trabalho elaborou um modelo computacional representativo das relações entre os componentes determinantes do comportamento do sistema de ensino superior que permitiu a execução de simulações de diferentes cenários para avaliação da adoção de políticas públicas. Utilizando a metodologia de Dinâmica de Sistemas e abordando o ensino superior como um sistema complexo, utilizou-se um paralelo da qualidade da educação sob a ótica da gestão de operações que utiliza o grau de atendimento das demandas do cliente como parâmetro. Para levantamento das características do ensino superior brasileiro foi realizada uma revisão da literatura, seguida de uma série de entrevistas com profissionais ligados ao ensino superior, incluindo gestores de instituições de ensino superior, coordenadores de cursos de graduação, especialistas em educação e especialistas em pesquisa, englobando instituições públicas e privadas de três regiões do país: sul, sudeste e nordeste. Foram identificados três principais clientes que tiveram suas demandas do ensino superior representadas no modelo: estudantes, empregadores e a sociedade. Adotando a habilitação financeira de estudantes a partir de financiamentos, bolsas ou vagas em instituições públicas como o principal fator foco de políticas públicas, foram realizadas simulações de nove diferentes cenários futuros até 2060. Foram considerados três níveis distintos de ofertas de educação superior, com os cenários distribuindo os focos da habilitação financeira de formas diferentes entre eles. Além disso, as simulações também consideraram a variação na demanda por profissionais formados nestes três níveis. Os resultados demonstraram cenários que variaram entre pouco efeito na produtividade, um ganho maior no curto prazo e um ganho maior no longo prazo. As simulações permitiram também identificar uma forte demanda pelo ensino superior no Brasil, sendo que o fator limitante para ingresso se demonstrou ser puramente a questão financeira, não havendo barreira para entrada em função de baixa qualidade da formação anterior dos estudantes. Como contribuições teóricas o processo de modelagem estabeleceu um modelo de estratificação do ensino superior que permite avaliar o seu desempenho de forma desagregada. Como contribuições práticas, o modelo gerado pode ser utilizado para aprendizado e testes de ações de forma a auxiliar no processo de tomada de decisão por gestores públicos. Finalmente o modelo sugere alguns aspectos que foram desconsiderados na modelagem como focos de estudos futuros. / This study developed a computational model representing the relations between the behavior determinants of the higher education system that was used to run different simulation scenarios in order to evaluate the adoption of public policies. Using Systems Dynamics and approaching higher education as a complex system, the analisys used the quality perspective from operations management that uses satisfaction of customers needs as a parameter for quality. A literature review was carried out to survey the characteristics of Brazilian higher education, followed by a series of interviews with professionals related to higher education, including managers of higher education institutions, coordinators of undergraduate courses, education specialists and research specialists, including public and private institutions in three regions of the country: South, Southeast and Northeast. Three main clients were identified who had their higher education needs represented in the model: students, employers and society. Adopting the financial enabling of students from financing, scholarships or acceptance in public institutions as the main focus of public policies, simulations of nine different future scenarios were carried out until 2060. Three distinct levels of offerings of higher education were considered, with the scenarios distributing the foci of financial enablement in different proportions among them. The simulations also considered the variation in demand for professionals educated at these three different levels. The results showed scenarios that varied between little effect on productivity, a greater gain in the short term and a greater gain in the long term. The simulations also demonstrated a strong demand for higher education in Brazil, and the limiting factor for admission was shown to be purely financial reasons, with no barrier to entry due to poor quality of the students\' previous education. As theoretical contributions, the modeling process established a stratification model of higher education that allows its performance evaluation in a disaggregated way. As a practical contribution, the generated model can be used for learning and testing of actions in order to assist in the decision making process by public managers. Finally the model suggests some aspects that were disregarded in the modeling as possible foci for future studies.
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Complex Systems Approach for Simulation & Analysis of Socio-Technical Infrastructure Systems - An Empirical DemonstrationJanuary 2020 (has links)
abstract: Over the past century, the world has become increasingly more complex. Modern systems (i.e blockchain, internet of things (IoT), and global supply chains) are inherently difficult to comprehend due to their high degree of connectivity. Understanding the nature of complex systems becomes an acutely more critical skill set for managing socio-technical infrastructure systems. As existing education programs and technical analysis approaches fail to teach and describe modern complexities, resulting consequences have direct impacts on real-world systems. Complex systems are characterized by exhibiting nonlinearity, interdependencies, feedback loops, and stochasticity. Since these four traits are counterintuitive, those responsible for managing complex systems may struggle in identifying these underlying relationships and decision-makers may fail to account for their implications or consequences when deliberating systematic policies or interventions.
This dissertation details the findings of a three-part study on applying complex systems modeling techniques to exemplar socio-technical infrastructure systems. In the research articles discussed hereafter, various modeling techniques are contrasted in their capacity for simulating and analyzing complex, adaptive systems. This research demonstrates the empirical value of a complex system approach as twofold: (i) the technique explains systems interactions which are often neglected or ignored and (ii) its application has the capacity for teaching systems thinking principles. These outcomes serve decision-makers by providing them with further empirical analysis and granting them a more complete understanding on which to base their decisions.
The first article examines modeling techniques, and their unique aptitudes are compared against the characteristics of complex systems to establish which methods are most qualified for complex systems analysis. Outlined in the second article is a proof of concept piece on using an interactive simulation of the Los Angeles water distribution system to teach complex systems thinking skills for the improved management of socio-technical infrastructure systems. Lastly, the third article demonstrates the empirical value of this complex systems approach for analyzing infrastructure systems through the construction of a systems dynamics model of the Arizona educational-workforce system, across years 1990 to 2040. The model explores a series of dynamic hypotheses and allows stakeholders to compare policy interventions for improving educational and economic outcome measures. / Dissertation/Thesis / Doctoral Dissertation Systems Engineering 2020
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New Approaches for Studying Food EnvironmentsGlickman, Alannah 25 August 2022 (has links)
No description available.
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Integrated Model to Plan Advanced Public Transportation SystemsBang, Chulho 28 December 1998 (has links)
The primary objective of this study is to develop an integrated public transportation planning framework to evaluate and plan Advanced Public Transportation Systems (APTS). With this purpose, a systems approach point of view is adopted to study the influence of new APTS technology in supply and demand transit variables. In this project the Systems Dynamics methodology is adopted to track the dynamic behavior of model variables and feedback loops forming among them. The proposed framework is illustrated in a case study involving automated vehicle location systems (AVL) applied to a small transit community.
The proposed approach follows the same steps of the Systems Dynamics method; First, identify some key variables which are not only susceptive to AVL technology but also affect the supply-demand relationship of a bus transit environment. Second, trace and simplify the causal relationships of the variables considering impacts of facility supply changes to passenger demand responses and vice versa. To accomplish this, four detailed sub-models representing parts of the transit system are developed and combined under the Systems Dynamics methodology point of view. Theses Sub-models are: 1) demography, 2) urban transportation planning, 3) bus operations, and 4) evaluation. Finally, to validate the model procedure, the model is applied to a case study. This study attempts to encompass as many as possible factors around a bus transit system environment which can be impacted by new APTS technology to illustrate the use of the proposed framework. Some of these factors include: 1) Demographic characteristics; 2) urban or social activity of the study area and 3) changes to transportation facilities. The case study illustrates how the physical characteristics of the transit systems such as traffic demand, traffic conditions along the transit route, route layout, and bus performance can be affected by the new technology.
Since APTS impacts are time dependent a continuous multi-loop simulation technique is adopted to track dynamic changes of all model variables. The analysis of the transit system is carried over a 20-year life cycle to illustrate the long term dynamics of the feedback structures inherent in the model.
<i>[Vita removed Aug. 2, 2010. GMc]</i> / Ph. D.
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Dynamic systems analysis of fossil dinoflagellates from the Atlantic Coastal Plain, USACawley, Jon Clayton 18 September 2008 (has links)
Dynamic Systems modeling suggests that complex coastal dinoflagellate biosystems can be modeled using environmental parameters such as temperature, salinity, and bulk nutrient levels. The former Salisbury Embayment of northern Virginia and Maryland is modeled here, using STELLA I and FORTRAN models based on physical oceanography and temperature, salinity, and nutrient conditions of the modern Yellow Sea. In these models, dinoflagellate assemblages are predicted based on environmental conditions associated with depth.
Cluster analyses of fossil dinoflagellate frequency data from Tertiary Pamunky Group (Aquia and Nanjemoy Formations) of the Salisbury Embayment produce 17 discrete groupings. Samples within the Salisbury fossil cluster groups are statistically similar (via ANOVA analysis), but not the same. Therefore they represent paleocommunity types rather than paleocommunities. Although individual sinofiagellate species recur in similar environmental settings, the paleocommunity types do not appear to repeat.
In the past, such associations have been used as depth indicators. It is suggested here that they relate to estuarine, nearshore, and offshore coastal regions because of the temperature, salinity, and nutrient conditions of each.
In the modern Yellow Sea, nearshore and offshore regions are separated by discrete lateral fronts in some areas, and by gradational regions of mixing in others. Both types of water mass boundaries are modeled in this study. Results suggest that evidences that discrete water mass boundaries might have occurred between some fossil dinoflagellate associations. Circulation patterns of the Salisbury Embayment may have been roughly similar to those of the modern Yellow Sea. / Master of Science
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Modeling the dynamics of software competition to find appropriate openness and pricing strategyRatnarajah, Thanujan 22 February 2008 (has links)
Software firms can use open source development model combined with proprietary development model to increase their profitability. Open source development models can help software firms create products with better technical features at a lower price. Since open source development is a community based development method the popularity of the software among customers will also increase. Using open source development method with proprietary method will also require firms to sell the product at a lower price. This creates a challenge for the firms to find the optimal price and level of openness to maximize their profit.
Using the systems dynamics methodology, development, employment and customer choice for a typical software firm was captured in a simulation model to understand the dynamics of the software firm in a competitive market and to find the optimal level of openness and price. The model was built based on previous research literature, various software models and from the author's understanding of the software industry.
Our analysis suggests that in a fast evolving market where customers spend less time researching and shopping for a software product (Antivirus market VS Operating Systems market), companies should maintain lower level of openness and higher proprietary type development to increase the Net Present Value of the organization. The software firm could benefit from a higher level of openness in a market where the customers base their purchasing decision on the popularity and compatibility of the software and strong network effects are present (e.g. Business intelligence software). / Master of Science
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Tomada de decisão em opções estratégicas : proposta de um método de avaliação sistêmico e dinâmicoMorandi, Maria Isabel Wolf Motta 30 October 2017 (has links)
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Previous issue date: 2017-10-30 / UNISINOS - Universidade do Vale do Rio dos Sinos / As decisões estratégicas visam a operacionalizar a estratégia da empresa a fim de alcançar as metas traçadas, as quais, embora possam ser de múltiplas naturezas, têm como fim maior ampliar os retornos de acionistas e o valor da própria empresa. O processo de orçamentação de capital, mais especificamente a etapa de avaliação e seleção de projetos, fornece bases para escolher as opções de maior retorno. No entanto, os métodos tradicionais apresentam lacunas, em especial no que tange à consideração dos impactos sistêmicos provocados pelo exercício de uma opção estratégica e das incertezas presentes no processo de decisão estratégica. Nesse sentido, o objetivo desta pesquisa é a proposição de um método de avaliação de opções estratégicas de investimento que funcione de maneira sistêmica e dinâmica, ou seja, que considere como as reações dos atores e as incertezas impactam no resultado da opção escolhida. Para tanto, a Design Science Research foi o método selecionado para conduzir esta pesquisa, cujo resultado principal é a proposição e avaliação do método de avaliação das opções estratégicas do NPV sistêmico e dinâmico, ou seja, do NPV resultante da avaliação da opção estratégica considerando a reação dos atores nos diversos cenários futuros. O método desenvolvido foi aplicado em uma empresa do ramo de mineração que atende tanto as heurísticas de construção como as heurísticas contingenciais identificadas no processo de construção do artefato. A aplicação permite avaliar satisfatoriamente o método proposto, bem como identificar possíveis refinamentos. Os resultados obtidos evidenciam que o método proposto traz contribuições teóricas e gerenciais. Do ponto de vista da teoria, aponta-se a proposição do conceito e o construto do NPV sistêmico e dinâmico, bem como a possibilidade de avaliar quantitativamente a significância das incertezas críticas na formulação dos cenários. Do ponto de vista gerencial, a possibilidade de avaliar sistêmica e dinamicamente as opções estratégicas, verificando os efeitos sinérgicos entre elas e a sua robustez frente a diferentes cenários, constitui-se em uma contribuição ao processo de tomada de decisão. / Strategic decisions aim to operationalize the company's strategy in order to reach its goals, which, although it may be of multiple natures, seek to increase the returns for the shareholders and the value of the company itself. The capital budgeting process, more specifically the project evaluation and selection stages, provides the basis for selecting the highest return options. However, the traditional methods present gaps, especially regarding the consideration of the systemic impacts caused by the exercise of a strategic option, and the uncertainties present in the strategic decision process. In this sense, the objective of this research is the proposition of a method to evaluate the strategic options in a systemic and dynamic way, that is, that considers how the reactions of the actors and the uncertainties impact on the result of the chosen option. Design Science Research was the method selected to conduct this research. The artifact is the strategic options evaluation method, which aims to calculate the systemic and dynamic NPV, that is, the taking into account the reaction of the actors in the various future scenarios. The developed method was applied in a mining company that satisfy both the construction heuristics and the contingency heuristics identified in the artifact construction process. This application allowed to satisfactorily evaluate the proposed method, as well as to identify possible refinements. From the results, it was possible to verify both the theoretical and the managerial contributions. From the theoretical point of view, the main contribution is the concept and the construct of the systemic and dynamic NPV. A secondary contribution is a toll to evaluate, in a quantitative way, the significance of the critical uncertainties in the formulation of the scenarios. From the managerial point of view, the possibility of systematically and dynamically evaluating the strategic options, evaluating the synergistic effects between them and their robustness in the different scenarios, constitutes a contribution to the decision-making process.
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Gestão da cadeia de suprimentos na indústria citrícola: uma proposta de modelo de planejamento integrado utilizando dinâmica de sistemasFerreira, José Orlando 12 December 2014 (has links)
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Previous issue date: 2014-12-12 / Suitable coordination systems are crucial to the sustained competitiveness of agribusiness systems. Nevertheless, some agribusiness systems have serious deficiencies in their integrated planning, generating with negative disputes between the members in the chain, which can lead in many cases to the loss of competitiveness. The orange agribusiness system, which has a significant importance as a currency generator and employment, not only in Brazil but also in many other countries, has faced serious problems of competitiveness. Disease threats, particularly, with the "greening" as the most critical, additionally the continuous competition for land with the sugarcane agribusiness system, have led the so-called "citrus belt" moving increasingly towards the southern state of São Paulo. This situation has led to increased costs and reducing the productivity and efficiency throughout the whole chain. The Brazilian citrus industry should search for urgent solutions, which cannot only bring longevity to the business, but also as a more critical issue: their own survival. Thus, this study aims to verify whether the gradual introduction of new varieties of orange and the development of a model of integrated planning within the technical of system dynamics can contribute to improve the performance and the competitiveness of this agribusiness system. The research method used was deductive hypothetical with the necessary information was gathered through semi-structured questionnaires and personal interviews with agents in the sector. The model was applied to the part of the citrus production chain, which covers the members of agricultural production and industrial processing. The results of the developed model showed that there are significant potential gains in performance, reflected in the increased EBITDA margin on the industrial processing side and in the net income per hectare and the price of the orange box on the agricultural production side, if they established together an integrated planning of production, crop-season to crop-season. / Sistemas de coordenação adequados são vitais à competitividade sustentada dos sistemas agroindustriais. Apesar disso, alguns sistemas agroindustriais apresentam sérias deficiências em planejamento integrado, gerando disputas acirradas entre os seus agentes, os quais podem levar, em muitos casos, a perdas de competitividade. O sistema agroindustrial da laranja, que tem uma importância significativa como setor gerador de divisas e de empregos, não somente no Brasil, mas em diversos outros países, tem enfrentado sérios problemas de competitividade. As ameaças de doenças, tendo o greening como a principal, bem como a constante competição por terras com o sistema agroindustrial da cana-deaçúcar, têm levado o denominado "cinturão citrícola" a mover-se cada vez mais para o Sul do Estado de São Paulo. Esta situação tem levado a um aumento de custos e de perdas de eficiência e produtividade ao longo da cadeia como um todo. A citricultura brasileira deve buscar em caráter de urgência soluções que possam não somente trazer a perenidade ao negócio, mas também como a uma questão mais crítica: a sua própria sobrevivência. Assim, este trabalho tem como objetivo principal verificar se mecanismos de planejamento integrado, envolvendo a produção no campo e a indústria citrícola, podem melhorar o desempenho competitivo deste SAI. Um modelo utilizando dinâmica de sistemas foi desenvolvido para avaliar esta hipótese. O método de pesquisa utilizado foi o hipotético dedutivo, tendo as informações sido coletadas através de entrevistas pessoais e questionários semiestruturados com os agentes do setor. O modelo foi aplicado na parte da cadeia de produção citrícola que envolve os elos da produção agrícola e de processamento industrial. Os resultados do modelo desenvolvido demonstraram que existem ganhos potenciais expressivos de desempenho, refletidos no aumento da margem de EBITDA do lado do processamento industrial e do lucro líquido por hectare e do preço da caixa de laranja do lado da produção agrícola, se estes se coordenarem para realizarem planejamentos integrados de produção safra a safra.
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Influences of External Literacy Assessment on Curricular Decisions: A Systems-Based Study of a Local School DistrictLarson, Tiffany R 08 1900 (has links)
National and state-based assessments have been a common practice for the past several decades. These assessments often come with high-stake consequences for students and schools, which tends towards the creation of a test-centric environment where educators prioritize test-based instruction to prepare students to be successful on those assessments. The over-arching purpose of this qualitative study was to explore how mandated high-stakes testing influences educators specifically within a complex system by first seeking to identify ways educators at different levels within the system—the classroom, campus, and district levels—perceive these testing influences. This study is based on complexity theory with a particular focus on complex adaptive systems (CAS) and frameworks from human systems dynamics (HSD), which helped to identify key tensions within a complex learning ecology. This study used thematic analysis of interview data from the classroom, campus, and district levels. Analysis also included mapping the emergent themes and patterns onto a CAS model for each level. Findings revealed a tension between a complicated, linear approach and a complex approach to curricular and instructional decisions that is moving those decisions ever closer to standardization. This study includes implications and recommendations for balancing these tensions for a healthy, complex learning ecology.
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Planejamento de processos de peen forming baseado em modelos analíticos do jato de granalhas e do campo de tensões residuais induzidas na peça. / Peen forming process planning based on analytical models of the shots\' jet and residual stress fields induced on a plate.Leite, Ricardo Augusto de Barros 18 July 2016 (has links)
Peen forming é um processo de conformação plástica a frio de laminas ou painéis metálicos através do impacto de um jato regulado de pequenas esferas de aço em sua superfície, a fim de produzir uma curvatura pré-determinada. A aplicação da técnica de shot peening como um processo de conformação já é conhecida da indústria desde a década de 1940, mas a demanda crescente por produtos de grande confiabilidade tem impulsionado o desenvolvimento de novas pesquisas visando o seu aperfeiçoamento e automação. . O planejamento do processo de peen forming requer medição e controle de diversas variáveis relacionadas à dinâmica do jato de granalhas e à sua interação com o material a ser conformado. Conforme demonstrado por diversos autores, a velocidade de impacto é uma das variáveis que mais contribui para a formação do campo de tensões residuais que leva o material a se curvar. Neste trabalho é apresentado um modelo dinâmico simplificado que descreve o movimento de um grande número de pequenas esferas arrastadas por um fluxo de ar em regime permanente e sujeitas a múltiplas colisões entre si e com a peça a ser conformada. Simulações deste modelo permitiram identificar a correlação entre o campo de velocidades das granalhas e os demais parâmetros do processo. Mediante a aplicação da técnica de projeto de experimentos pôde-se estimar os valores dos parâmetros que otimizam o processo. Ao final, elaborou-se um algoritmo que permite realizar o planejamento de processos de peen forming, ou seja, determinar os valores desses parâmetros, de modo tal a produzir uma curvatura pré-determinada em uma placa metálica originalmente plana. / Peen forming is a plastic cold work process of shaping a metallic sheet or panel through the impact of a regulated blast of small round steel shots on its surface, in order to produce a previously desired curvature. The application of the shot peening as a forming process has been a known technique in the industry since the decade of 1940, but the increasing demand for products of high reliability have pushed the development of new research in order to enhance and automate it. Peen forming process planning requires the measurement and control of several variables concerning the dynamics of the shot jet and its interaction with the piece to be shaped. As previously shown by several authors, impact velocity is one of the variables that most contribute to the development of the residual stress field that causes the material to bend. In this article we present a simplified dynamical model describing the motion of a large number of small spheres (shot) dragged by an air flow in steady conditions and exposed to multiple collisions with each other and with the piece to be shaped. Computer simulations of this model allowed to identify correlations between the shot field velocity and the parameters of the process. Applying design of experiments techniques it was possible to estimate the value of parameters that optimize the process. It was, then, elaborated an algorithm that enables peen forming process planning, allowing the determination of the parameters, in order to make a predetermined bending in a metallic plate originally plane.
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