Com mais de metade de sua produção exportada e participação de aproximadamente um terço do mercado mundial, atualmente o Brasil é o maior exportador de açúcar e, portanto, espera-se que os preços do mercado físico do açúcar no Brasil apresentem algum grau de relacionamento os preços internacionais desta commodity, que são representados pelas cotações dos contratos futuros das bolsas de Nova Iorque (NYBOT) e de Londres (LIFFE) – primeiros vencimentos. No presente estudo são analisadas as relações entre os logaritmos das médias semanais dos preços domésticos de açúcar, representados pelo preço do Estado de São Paulo, principal produtor nacional, e preços internacionais convertidos em moeda brasileira. Utilizando os critérios de Akaike e Schwarz, foi determinado o número de defasagens auto-regressivas necessárias para ajustar modelos com a finalidade de testar a existência de raiz unitária, cujos resultados apontam para a estacionariedade das séries em torno de uma tendência determinista. A partir dos resíduos obtidos na estimação de modelos univariados auto-regressivos para cada variável, foram obtidas as funções de correlação cruzada (FCC) para cada par de variáveis usado no teste de causalidade. Os resultados das FCCs apontam tanto a existência de relação contemporânea significativa, como causalidade dos preços das bolsas internacionais para os preços domésticos do açúcar, sendo mais expressiva a relação causal das cotações dos contratos futuros da bolsa de Nova Iorque para os preços do mercado físico do açúcar no Brasil. Com base nesses resultados, foram especificados modelos que tinham como finalidade analisar o processo de transmissão de preços entre os mercados doméstico e internacional. Para evitar multicolinearidade, optou-se pela não inclusão de defasagens da variável dependente como explicativas nestes modelos e, para contornar problemas associados à correlação de resíduos nas equações ajustadas, as variáveis foram filtradas conforme a metodologia de Cochrane-Orcutt, fundamentando-se nos resultados da função de autocorrelação dos resíduos dos modelos ajustados de forma iterativa. As elasticidades obtidas nas funções de transmissão de preços indicam que os valores passados das cotações da NYBOT são referência para a formação de preço do mercado doméstico de açúcar, e que a influência contemporânea entre os preços das bolsas internacionais e o preço doméstico é pequena. Como a participação do Brasil no mercado internacional de açúcar é elevada, espera-se que de alguma maneira aspectos relativos ao mercado doméstico brasileiro dessa commodity afetem os preços internacionais. Dessa forma, buscou-se analisar o impacto que a produção brasileira de açúcar, a qual define o potencial de exportação dessa commodity pelo Brasil, tem sobre a formação do preço no mercado internacional. Para isso foi ajustada uma função utilizando como representativo do preço de açúcar no mercado internacional a média das cotações do contrato futuro de açúcar na bolsa de Nova Iorque no ano-safra internacional, isto é, entre setembro de um ano a agosto do subseqüente. Como variáveis explicativas foram considerados: o estoque inicial de cada ano-safra, a produção de açúcar do Brasil e a produção de açúcar dos demais países do mundo, também por ano-safra. Os resultados apontam que o direcionamento de mais matéria-prima para a produção de açúcar, considerando as baixas taxas de crescimento do consumo desse produto no mercado interno, tem efeito negativo e significativo no nível de preço a vigorar no mercado internacional. Isto poderia comprometer a rentabilidade do setor, não só porque os preços do açúcar exportado cairiam, mas também porque os menores preços do mercado internacional estariam afetando os recebidos pelo açúcar comercializado no mercado interno. / With more than a half of its production exported and about 30% of market share in the world sugar market, nowadays Brazil is the world’s leading exporter of sugar. So, it’s expected that the sugar physical prices in the State of São Paulo (CEPEA), Brazil´s leading production region, have any sort of relation with the international prices of this commodity. These international prices are represented by the nearby quotes of the sugar contracts at New York Board of Trade (NYBOT) and at London International Financial Futures and Options Exchange (LIFFE), both multiplied by the Brazilian currency exchange rate. The present study analyses the relations between the logarithms of the domestic and international weekly means of sugar prices. The number of auto-regressive lags necessaries to ajust models was determined by Akaike and Scharwz criterions, which objective was to test the existence of unit root. The results pointed to stationary series around deterministic trends. Through the residual data of auto-regressive univariated models that were estimated to each of the variables, it was obtained the cross correlation function (CCF) to each pair of variables to which the causality was tested. The CCF results indicated a significative contemporany relation between the variables and also causality from the international quotes to State of São Paulo domestic prices, mainly from NYBOT. Based on these results, it was obtained the number of lags of the explicative variable to specify the transmission price models between domestic and international sugar prices. To prevent multicolinearity, it was opted to not include lags of dependent variable as explicative variables, and, to skirt problems related to the correlation in the residual data in the adjusted equations, the variables were filtered by the Cochrane-Orcutt methodology, following the indicatives of the autocorrelation function (ACF) of the residual data from adjusted models in an interactive form. The elasticities obtained in the price transmission functions indicated that the past values of NYBOT quotes are reference to CEPEA prices, and that the contemporany influence between domestic and international prices is small. Considering that Brazilian share in the sugar international market is expressive, it’s expected that aspects related to Brazilian domestic market should cause any affect in the international prices level. So, to analyze the impact that Brazilian production of sugar, which defines the potential of exportation of this commodity for Brazil, has on the formation of the price in the international market, it was adjusted a function that uses as representative of the sugar price in the international market the mean of NYBOT nearby quotes between September to August (of the subsequent year). The variables international beginning stocks, Brazilian sugar production and rest of the world sugar production, all of them measured in the international sugar-marketing year, were considered as explicative ones. The results pointed that an increase in the Brazilian sugar cane production (in order to produce sugar), considering the low rates of the consumption evolution in the Brazilian domestic market, would have a negative and significant effect in the international sugar prices level. This event would affect the yield of sugar sector, not only because the sugar international price would decrease, but also because the lower prices in the international market would reduce the Brazilian domestic prices.

Recent natural disasters have highlighted the need to evacuate people as quickly as possible. During hurricane Rita in 2005, people were stuck in queue buildups and large scale congestions, due to improper use of capacity, planning and inadequate response to vehicle breakdown, flooding and accidents. Every minute is precious in situation of such disaster scenarios. Understanding evacuation demand loading is an essential part of any evacuation planning. One of the factors often understood to effect evacuation, but not modeled has been the effect of a previous hurricane. This has also been termed as the 'Katrina Effect', where, due to the devastation caused by hurricane Katrina, large number of people decided to evacuate during Hurricane Rita, which hit Texas three weeks after Katrina hit Louisiana. An important aspect influencing the rate of evacuation loading is Evacuation Preparation Time also referred to as 'Mobilization time' in literature. A methodology to model the effect of a recent past hurricane on the mobilization times for evacuees in an evacuation has been presented utilizing simultaneous estimation techniques. The errors for the two simultaneously estimated models were significantly correlated, confirming the idea that a previous hurricane does significantly affect evacuation during a subsequent hurricane. The results show that the home ownership, number of individuals in the household, income levels, and level/risk of surge were significant in the model explaining the mobilization times for the households. Pet ownership and number of kids in the households, known to increase the mobilization times during isolated hurricanes, were not found to be significant in the model. Evacuation operations are marred by unexpected blockages, breakdown of vehicles and sudden flooding of transportation infrastructure. A fast and accurate simulation model to incorporate flexibility into the evacuation planning procedure is required to react to such situations. Presently evacuation guidelines are prepared by the local emergency management, by testing various scenarios utilizing micro-simulation, which is extremely time consuming and do not provide flexibility to evacuation plans. To gain computational speed there is a need to move away from the level of detail of a micro-simulation to more aggregated simulation models. The Cell Transmission Model which is a mesoscopic simulation model is considered, and compared with VISSIM a microscopic simulation model. It was observed that the Cell Transmission Model was significantly faster compared to VISSIM, and was found to be accurate. The Cell Transmission model has a nice linear structure, which is utilized to construct Linear Programming Problems to determine optimal strategies. Optimization models were developed to determine strategies for optimal scheduling of evacuation orders and optimal crossover locations for contraflow operations on freeways. A new strategy termed as 'Dynamic Crossovers Strategy' is proposed to alleviate congestion due to lane blockages (due to vehicle breakdowns, incidents etc.). This research finds that the strategy of implementing dynamic crossovers in the event of lane blockages does improve evacuation operations. The optimization model provides a framework within which optimal strategies are determined quickly, without the need to test multiple scenarios using simulation. Destination networks are the cause of the main bottlenecks for evacuation routes, such aspects of transportation networks are rarely studied as part of evacuation operations. This research studies destination networks from a macroscopic perspective. Various relationships between network level macroscopic variables (Average Flow, Average Density and Average speed) over the network were studied. Utilizing these relationships, a "Network Breathing Strategy" was proposed to improve dissipation of evacuating traffic into the destination networks. The network breathing strategy is a cyclic process of allowing vehicles to enter the network till the network reaches congestion, which is followed by closure of their entry into the network until the network reaches an acceptable state. After which entrance into the network is allowed again. The intuitive motivation behind this methodology is to ensure that the network does not remain in congested conditions. The term 'Network Breathing' was coined due to the analogy seen between this strategy to the process of breathing, where vehicles are inhaled by the network (vehicles allowed in) and dissipated by the network (vehicles are not allowed in). It is shown that the network breathing improves the dissipation of vehicle into the destination network. Evacuation operations can be divided into three main levels: at the origin (region at risk), routes and destination. This research encompasses all the three aspects and proposes a framework to assess the whole system in its entirety. At the Origin the demand dictates when to schedule evacuation orders, it also dictates the capacity required on different routes. These breakthroughs will provide a framework for a real time Decision Support System which will help emergency management official make decisions faster and on the fly.

Denna uppsats behandlar ämnet internkommunikation. Vi har valt att genomföra en undersökning om Polismyndigheten Värmlands internkommunikation då de innehar ett stort ansvar att bevara trygghet och säkerhet i samhället. Polismyndigheten har även stora krav på sig idag gällande dialog och grad av kommunikation inom organisationen för att effektivisera det polisiära arbetet. Syftet med denna uppsats är att erhålla en insikt om den interna kommunikationens funktion och hur den gestaltas utifrån chefernas och de anställdas perspektiv. I denna uppsats använder vi oss utav relevanta teorier inom organisationskommunikation, internkommunikation, organisationsidentitet, organisationskultur och kommunikationsmodeller. Vårt tillvägagångssätt för att besvara uppsatsens syfte var att använda oss utav två skräddarsydda frågeställningar för att möjliggöra en helhetsbild och en djupare insikt på våra utvalda teoretiska områden. ”Hur upplever cheferna på polismyndigheten Värmland internkommunikationen?” ”Hur upplever de anställda på polismyndigheten Värmland internkommunikationen?” I denna undersökning använde vi oss av kvalitativa samtalsintervjuer och en kvalitativ fokusgrupp. Det resultat vi lyckades utvinna visade att internkommunikationen hos de utvalda cheferna och anställda upplevdes som både positiv och negativ. Polismyndighetens internkommunikation har enligt cheferna genomgått en positiv utveckling. Enligt chefernas utsagor är polismyndigheten en arbetsplats med goda möjligheter för dialog mellan ledning och anställda och klara riktlinjer för hur internkommunikation ska bedrivas. Dock finns det rum för förbättring då det upplevs vara svårt att förmedla information som även filtreras på ett felaktigt sätt och skapar missförstånd. De anställda på polismyndigheten Värmland gav en helt annan bild då det dagliga arbetet präglas av orättvisor, bristfällig internkommunikation som skapar förvirring och svårigheter att överblicka vem som har ansvar för vad inom organisationen. / This bachelor thesis treats the subject of internal communication. We have chosen to carry through a research about the police department of Värmland's internal communication since they have big responsibility to preserve safety and security in society. The police department has these days greater demands regarding how to conduct dialogue and the level of communication within the organization to further the efficiency of police work. The main purpose of this bachelor thesis is to obtain insight about the internal communication functions and how it is presented from the managers as well as the employees perspective. In this thesis we are using relevant theories regarding organizational communication, internal communication, organization identity, organization culture and communication models. Our approach to answer the purpose of this thesis was to use two customized questions to enable us to get a overall view and a deeper insight of our chosen theoretical framework. “How do the managers perceive the internal communication in the police department of Värmland?” “How do the employees perceive the internal communication in the police department of Värmland?” In this study we used qualitative interviews and a qualitative focus group. The result we obtained, showed that, internal communication with the chosen managers and the employees had both positive and negative experiences. The police department of Värmland's internal communication has gone through a positive development according to the managers. According to the managers, the police department of Värmland has a healthy working environment that offers good possibilities for dialogue between management and employees, and also clear guidelines for how the internal communication has to be conducted. However, there is room for improvement, since some experience it to be hard to communicate information that filters wrongly and creates misunderstanding. But the employees gave us a completely different picture since the daily work characterized in injustice, faulty internal communication that creates confusion and difficulties to get an overview about who has what responsibilities in the organization.

This research contributes to the state of the art and state of the practice in solving a very important and computationally challenging problem in the areas of urban transportation systems, operations research, disaster management, and public policy. Being a very active topic of research during the past few decades, the problem of developing an efficient and practical strategy for evacuation of real-sized urban traffic networks in case of disasters from different causes, quickly enough to be employed in immediate disaster management scenarios, has been identified as one of the most challenging and yet vital problems by many researchers. More specifically, this research develops fast methods to find the optimal integrated strategy for traffic routing and traffic signal control to evacuate real-sized urban networks in the most efficient manner. In this research a solution framework is proposed, developed and tested which is capable of solving these problems in very short computational time. An efficient relaxation-based decomposition method is proposed, implemented for two evacuation integrated routing and signal control model formulations, proven to be optimal for both formulations, and verified to reduce the computational complexity of the optimal integrated routing and signal control problem. The efficiency of the proposed decomposition method is gained by reducing the integrated optimal routing and signal control problem into a relaxed optimal routing problem. This has been achieved through an insight into intersection flows in the optimal routing solution: in at least one of the optimal solutions of the routing problem, each street during each time interval only carries vehicles in at most one direction. This property, being essential to the proposed decomposition method, is called "unidirectionality" in this dissertation. The conditions under which this property exists in the optimal evacuation routing solution are identified, and the existence of unidirectionality is proven for: (1) the common Single-Destination System-Optimal Dynamic Traffic Assignment (SD-SODTA) problem, with the objective to minimize the total time spent in the threat area; and, (2) for the single-destination evacuation problem with varying threat levels, with traffic models that have no spatial queue propagation. The proposed decomposition method has been implemented in compliance with two widely-accepted traffic flow models, the Cell Transmission Model (CTM) and the Point Queue (PQ) model. In each case, the decomposition method finds the optimal solution for the integrated routing and signal control problem. Both traffic models have been coded and applied to a realistic real-size evacuation scenario with promising results. One important feature that is explored is the incorporation of evacuation safety aspects in the optimization model. An index of the threat level is associated with each link that reflects the adverse effects of traveling in a given threat zone on the safety and health of evacuees during the process of evacuation. The optimization problem is then formulated to minimize the total exposure of evacuees to the threat. A hypothetical large-scale chlorine gas spill in a high populated urban area (downtown Tucson, Arizona) has been modeled for testing the evacuation models where the network has varying threat levels. In addition to the proposed decomposition method, an efficient network-flow solution algorithm is also proposed to find the optimal routing of traffic in networks with several threat zones, where the threat levels may be non-uniform across different zones. The proposed method can be categorized in the class of "negative cycle canceling" algorithms for solving minimum cost flow problems. The unique feature in the proposed algorithm is introducing a multi-source shortest path calculation which enables the efficient detection and cancellation of negative cycles. The proposed method is proven to find the optimal solution, and it is also applied to and verified for a mid-size test network scenario.

<p>Instructional theories often view the work of instructors from a psychological perspective while playing little emphasis on the communicative aspects. However, there are vital communicational influences on and implications for instructional practice and the instructional process as a whole. As such, this work begins with the position that instruction is, in its entirety, a communicative process. A comparison is made between the three basic models of communication (transmission, interaction and transaction) and three main educational theories (behaviorism, cognitivism and constructivism). This comparison shows that there are alignments between the transmission model of communication and behaviorism, the interactive model of communication and cognitivism, and the transactional model of communication and constructivism. These similarities are explored over three major instructional activities – lesson planning, lesson delivery and assessment. Subsequently, three real-life scenarios were presented to illustrate how the three basic models of communication are manifested in the classroom. Given the applicability of the models of communication to the instructional process, the practical utility of approaching instruction from a communicative perspective is discussed. Potential implications for educational practitioners and scholars are discussed afterwards.</p>

Orientador: Rubén Augusto Romero Lázaro / Resumo: A análise de sistemas altamente complexos quando e analizado o problema de planejamento de expansão de redes de transmissão de longo prazo, é o foco principal deste trabalho. Os modelos e metodos propostos são aplicados ao problema de planejamento estático tradicional, que é um problema de otimização matemática classificado como NP-completo, não-linear inteiro misto. O qual envolve no investimento, variáveis operacionais contínuas e variáveis inteiras. O comportamento normal de cada sistema pode conter informação essencial para a criação de novos métodos, como os planos de corte baseados em cortes de diferença de ângulos para problemas de grande escala, o que é a base é o ponto de partida deste trabalho, derivando em desigualdades válidas é ciclos críticos. Os cortes angulares básicos reduzem o espaço de busca do problema e o tempo total de cálculo deste problema, enquanto ao método de inequações válidas que pode ser usado para fornecer limites inferiores sólidos no investimento ótimo do planejamento de transmissão, já que a diferença entre o modelo DC (modelo exato) e o modelo de transporte (modelo mais relaxado) são as restrições angulares. Os ciclos críticos têm sido desenvolvidos para melhoraralguns dos modelos tradicionais do problemas de planejamento da expansão da rede de transmissão de longo prazo. A razão por trás disso é a ausência da segunda lei de Kirchhoff, que completa a representação do sistema, mas aumenta a complexidade. Para resolver os problemas resultantes... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The analysis of highly complex systems when solving the long-term transmission network expansion planning problem is the main focus of this work. The proposed improved models and methodology are applied to the traditionalstatic planning problem, which is a mathematical optimization problem classified as NP-complete and mixed-integer nonlinear problem. It involves continuousoperating variables and integer investment variables. The normal behavior of each system can be shown essential information to the creation of new methods, as the cutting-planes based in bus-angle difference cuts for large-scale problems which were the starting point of this work, deriving in valid inequalities and critic cycles. The angular cuts aim to reduce the search space of the problem and the total computation time of this NP-hard problem as for the valid inequalities methodthat can be used to provide strong lower bounds on the optimal investment of the transmissionplanning, since the difference between the DC model (exact model) and the transport model (more relaxed model) are the angular constraints. Critic cycles has been develop in order to improve some of the traditional long-term transmission network expansion planning problem models. The reason behind it is the absence of second Kirchhoff’s law which completes the representationof the system, but increase the complexity. In order to solve the resulting problems, this work uses the modeling language AMPL with the solver CPLEX. In test systems w... (Complete abstract click electronic access below) / Doutor