Dissertations / Theses on the topic 'Index inversé'

Un nouveau moteur de recherche embarqué conçu pour les objets intelligents. Ces dispositifs sont généralement équipés d'extrêmement de faible quantité de RAM et une grande capacité de stockage Flash NANAD. Pour faire face à ces contraintes matérielles contradictoires, les moteurs de recherche classique privilégient soit la scalabilité en insertion ou la scalabilité en requête, et ne peut pas répondre à ces deux exigences en même temps. En outre, très peu de solutions prennent en charge les suppressions de documents et mises à jour dans ce contexte. nous avons introduit trois principes de conception, à savoir y Write-Once Partitioning, Linear Pipelining and Background Linear Merging, et montrent comment ils peuvent être combinés pour produire un moteur de recherche intégré concilier un niveau élevé d'insertion / de suppression / et des mises à jour. Nous avons mis en place notre moteur de recherche sur une Board de développement ayant un représentant de configuration matérielle pour les objets intelligents et avons mené de vastes expériences en utilisant deux ensembles de données représentatives. Le dispositif expérimental résultats démontrent la scalabilité de l'approche et sa supériorité par rapport à l'état des procédés de l'art
A new embedded search engine designed for smart objects. Such devices are generally equipped with extremely low RAM and large Flash storage capacity. To tackle these conflicting hardware constraints, conventional search engines privilege either insertion or query scalability but cannot meet both requirements at the same time. Moreover, very few solutions support document deletions and updates in this context. we introduce three design principles, namely Write-Once Partitioning, Linear Pipelining and Background Linear Merging, and show how they can be combined to produce an embedded search engine reconciling high insert/delete/update rate and query scalability. We have implemented our search engine on a development board having a hardware configuration representative for smart objects and have conducted extensive experiments using two representative datasets. The experimental results demonstrate the scalability of the approach and its superiority compared to state of the art methods

Ce mémoire présente l'étude d'un capteur chimique à fibre optique à gradient d'indice inversé basé sur la résonance de plasmons de surface. Des dispositifs optiques à prisme ou mettant en jeu des fibres optiques classiques en silice utilisant cette technique de mesure sont déjà commercialisés. L'objectif de notre travail a été de caractériser théoriquement et expérimentalement un nouveau type de fibre optique permettant d'accroître les performances de ce capteur et d'en simplifier l'instrumentation. Un état de l'art des capteurs à plasmons de surface est présenté. Les structures basées sur une fibre optique (unimodale, multimodale) font l'objet d'une présentation détaillée mettant en évidence les caractéristiques des montages employés ainsi que leurs performances respectives. Nous avons cherché à déterminer le profil d'indice de réfraction du cœur de la fibre rendant les angles d'incidence à l'interface cœur-gaine quasiment égaux quels que soient les rayons se propageant dans la fibre. Ceci a été réalisé en utilisant une source lumineuse ponctuelle monochromatique positionnée dans l'axe et à une distance définie de l'entrée de la fibre. Le profil idéal présente un gradient d'indice inversé très proche d'un profil parabolique inversé pour lequel l'indice est minimal au centre du cœur de la fibre. Une description des caractéristiques de cette fibre comprenant l'étude de la propagation des rayons a été réalisée. Le phénomène de plasmon de surface est ensuite décrit, de manière générale puis ses conditions d'excitation dans la fibre employée sont étudiées. Une étude expérimentale et théorique a été menée sur les paramètres les plus influents du capteur (nature et épaisseur du métal, position de la source ...). La présentation de deux applications pratiques (détection de traces de toluène dans un milieu aqueux et étude en temps réel du mécanisme de formation d'une monocouche auto-assemblée) montre les champs d'applications du dispositif optique simple développé.

The index of a subgroup of a group counts the number of cosets of that subgroup. A subgroup of finite index often shares structural properties with the group, and the existence of a subgroup of finite index with some particular property can therefore imply useful structural information for the overgroup. Although a developed theory of cosets in inverse semigroups exists, it is defined only for closed inverse subsemigroups, and the structural correspondences between an inverse semigroup and a closed inverse subsemigroup of finte index are much weaker than in the group case. Nevertheless, many aspects of this theory remain of interest, and some of them are addressed in this thesis. We study the basic theory of cosets in inverse semigroups, including an index formula for chains of subgroups and an analogue of M. Hall’s Theorem on counting subgroups of finite index in finitely generated groups. We then look at specific examples, classifying the finite index inverse subsemigroups in polycyclic monoids and in graph inverse semigroups. Finally, we look at the connection between the properties of finite generation and having finte index: these were shown to be equivalent for free inverse monoids by Margolis and Meakin.

La recherche d’images par contenu (CBIR) est une discipline de l’informatique qui vise à structurer automatiquement les collections d’images selon des critères visuels. Les fonctionnalités proposées couvrent notamment l’accès efficace aux images dans une grande base de données d’images ou l’identification de leur contenu par des outils de détection et de reconnaissance d’objets. Ils ont un impact sur une large gamme de domaines qui manipulent ce genre de données, telles que le multimedia, la culture, la sécurité, la santé, la recherche scientifique, etc.Indexer une image à partir de son contenu visuel nécessite d’abord de produire un résumé visuel de ce contenu pour un usage donné, qui sera l’index de cette image dans la collection. En matière de descripteurs d’images, la littérature est désormais trés riche: plusieurs familles de descripteurs existent, et dans chaque famille de nombreuses approches cohabitent. Bon nombre de descripteurs ne décrivant pas la même information et n’ayant pas les mêmes propriétés d’invariance, il peut être pertinent de les combiner de manière à mieux décrire le contenu de l’image. Cette combinaison peut être mise en oeuvre de différentes manières, selon les descripteurs considérés et le but recherché. Dans cette thése, nous nous concentrons sur la famille des descripteurs locaux, avec pour application la recherche d’images ou d’objets par l’exemple dans une collection d’images. Leurs bonnes propriétés les rendent très populaires pour la recherche, la reconnaissance et la catégorisation d'objets et de scènes. Deux directions de recherche sont étudiées:Combinaison de caractéristiques pour la recherche d’images par l’exemple: Le coeur de la thèse repose sur la proposition d’un modèle pour combiner des descripteurs de bas niveau et génériques afin d’obtenir un descripteur plus riche et adapté à un cas d’utilisation donné tout en conservant la généricité afin d’indexer différents types de contenus visuels. L’application considérée étant la recherche par l’exemple, une autre difficulté majeure est la complexité de la proposition, qui doit correspondre à des temps de récupération réduits, même avec de grands ensembles de données. Pour atteindre ces objectifs, nous proposons une approche basée sur la fusion d'index inversés, ce qui permet de mieux représenter le contenu tout en étant associé à une méthode d’accès efficace.Complémentarité des descripteurs: Nous nous concentrons sur l’évaluation de la complémentarité des descripteurs locaux existant en proposant des critères statistiques d’analyse de leur répartition spatiale dans l'image. Ce travail permet de mettre en évidence une synergie entre certaines de ces techniques lorsqu’elles sont jugées suffisamment complémentaires. Les critères spatiaux sont exploités dans un modèle de prédiction à base de régression linéaire, qui a l'avantage de permettre la sélection de combinaisons de descripteurs optimale pour la base considérée mais surtout pour chaque image de cette base. L'approche est évaluée avec le moteur de recherche multi-index, où il montre sa pertinence et met aussi en lumière le fait que la combinaison optimale de descripteurs peut varier d'une image à l'autre.En outre, nous exploitons les deux propositions précédentes pour traiter le problème de la recherche d'images inter-domaines, correspondant notamment à des vues multi-source et multi-date. Deux applications sont explorées dans cette thèse. La recherche d’images inter-domaines est appliquée aux collections photographiques culturelles numérisées d’un musée, où elle démontre son efficacité pour l’exploration et la valorisation de ces contenus à différents niveaux, depuis leur archivage jusqu’à leur exposition ou ex situ. Ensuite, nous explorons l’application de la localisation basée image entre domaines, où la pose d’une image est estimée à partir d’images géoréférencées, en retrouvant des images géolocalisées visuellement similaires à la requête
Content-Based Image Retrieval (CBIR) is a discipline of Computer Science which aims at automatically structuring image collections according to some visual criteria. The offered functionalities include the efficient access to images in a large database of images, or the identification of their content through object detection and recognition tools. They impact a large range of fields which manipulate this kind of data, such as multimedia, culture, security, health, scientific research, etc.To index an image from its visual content first requires producing a visual summary of this content for a given use, which will be the index of this image in the database. From now on, the literature on image descriptors is very rich; several families of descriptors exist and in each family, a lot of approaches live together. Many descriptors do not describe the same information and do not have the same properties. Therefore it is relevant to combine some of them to better describe the image content. The combination can be implemented differently according to the involved descriptors and to the application. In this thesis, we focus on the family of local descriptors, with application to image and object retrieval by example in a collection of images. Their nice properties make them very popular for retrieval, recognition and categorization of objects and scenes. Two directions of research are investigated:Feature combination applied to query-by-example image retrieval: the core of the thesis rests on the proposal of a model for combining low-level and generic descriptors in order to obtain a descriptor richer and adapted to a given use case while maintaining genericity in order to be able to index different types of visual contents. The considered application being query-by-example, another major difficulty is the complexity of the proposal, which has to meet with reduced retrieval times, even with large datasets. To meet these goals, we propose an approach based on the fusion of inverted indices, which allows to represent the content better while being associated with an efficient access method.Complementarity of the descriptors: We focus on the evaluation of the complementarity of existing local descriptors by proposing statistical criteria of analysis of their spatial distribution. This work allows highlighting a synergy between some of these techniques when judged sufficiently complementary. The spatial criteria are employed within a regression-based prediction model which has the advantage of selecting the suitable feature combinations globally for a dataset but most importantly for each image. The approach is evaluated within the fusion of inverted indices search engine, where it shows its relevance and also highlights that the optimal combination of features may vary from an image to another.Additionally, we exploit the previous two proposals to address the problem of cross-domain image retrieval, where the images are matched across different domains, including multi-source and multi-date contents. Two applications of cross-domain matching are explored. First, cross-domain image retrieval is applied to the digitized cultural photographic collections of a museum, where it demonstrates its effectiveness for the exploration and promotion of these contents at different levels from their archiving up to their exhibition in or ex-situ. Second, we explore the application of cross-domain image localization, where the pose of a landmark is estimated by retrieving visually similar geo-referenced images to the query images

Leaf area index (LAI), defined as the one sided green leaf area per unit ground area, is a key parameter in ecosystem process models. Owing to the large area of the earth's surface that they occupy, savanna ecosystems represent the third largest terrestrial carbon sink. There is considerable uncertainty however, as to the functioning of these ecosystems, particularly as they respond to land cover changes. Consequently, ecosystem process models constitute one of the best methods available for investigating the effect this may have on terrestrial carbon cycling. If these models are to be used over large areas however, they need to be parameterised. This thesis develops a methodology to estimate LAI in savanna ecosystems, using remotely sensed earth observation (EO) data, laboratory bidirectional reflectance measurements (BRDF), physically based canopy reflectance models (CRMs), and artificial neural networks (ANN). First, the scattering behaviour of Kalahari soils was characterised, by making laboratory BRDF measurements. Soils were shown to be highly non-Lambertian. These measurements were then used to parameterise three different CRMs. Modelled reflectances were assessed with respect to Landsat ETM+ and Terra-MODIS reflectances. Results showed that a 1-D turbid medium provided the closest fit to the measurements. A series of model sensitivity analyses (SA) were performed, and it was shown that reflectance in the red and shortwave infrared displayed greatest sensitivity to LAI, sensitivity in the near-infrared was negligible. Model inversions were performed with ANN and different waveband combinations, and LAI was estimated. The results showed that LAI could be estimated with high accuracy, an RMSE of 0.3 1, and 0.18, from ETM+ and MODIS measurements, respectively. These results were promising, and with further improvements to models, coupled with more accurate input data, will see the use of EO data play an increasingly important role in understanding the functioning of these savanna ecosystems.

En este trabajo extendemos el Teorema de la Función Inversa para funciones entre espacios de Banach al caso de aplicaciones Multivaluadas. En el inicio se define el concepto de aplicación multivaluada y se muestran algunos ejemplos. Luego, se estudia el concepto de semicontinuidad superior de aplicaciones multivaluadas. Para definir la derivada de una aplicación multivaluada se necesita los conceptos de cono contingente y cono tangente. Estos conceptos se definen y se caracterizan los elementos de estos conjuntos. Además se muestran algunas relaciones entre estos conjuntos en casos particulares. El estudio de estos conos se hace para definir la derivada de una aplicación multivaluada en la forma más semejante a la derivada de funciones. Luego, se enuncia y demuestra el Teorema de la Función Inversa para aplicaciones multivaluadas que es el tema central de este trabajo. Finalmente vemos la relación entre el Teorema de la Función Inversa para aplicaciones multivaluadas y el Teorema de la Aplicación Abierta uniforme y otras versiones más del teorema central.

La subasta inversa es una modalidad de selección introducida en la legislación peruana con el fin de modernizar la gestión del Estado y de hacer más eficientes y transparentes las compras estatales. Durante un período de 5 años, ha generado ahorros por más de  S/. 385 millones. A través de la subasta inversa, las entidades públicas enligen al proveedor de bienes o servicios comunes tomando en consideración únicamente los precios ofrecidos, mas no las características técnicas del bien o del servicio requerido, dado que estas se encuentran predeterminadas en las fichas técnicas que forman parte del Listado de Bienes y Servicios Comunes. Esta modalidad puede llevarse a cabo tanto en forma presencial (subasta inversa presencial) como en forma electrónica (subasta inversa electrónica). La primera de ellas se realiza en acto público, en presencia de  todos los postores, y la segunda se efectúa a través de internet.

El teorema de Brauer describe un procedimiento para modificar un autovalor del espectro de una matriz compleja y Rado lo extiende para modificar una parte del espectro.En los años cincuenta Perfect utiliza estos resultados para dar condiciones bajo la cual una colección de números reales sea el espectro de una matriz no negativa [6], [7]. Untrabajo debido a Suleimanova [12], junto con estas condiciones, dan origen al problema espectral inverso no negativo. Recientemente se han descrito varias condiciones suficientes basadas en los teoremas de Brauer y Rado para la realizacion de matrices no negativas con espectro real. En este trabajo profundizamos estas técnicas y se hace una recopilación de los resultados conocidos hasta el momento para el problema del espectro real inverso no negativo que utilizan el teorema de Brauer.

Reverse logistics is a concept of recent introduction and little known in companies of dairy products sector in Zulia state (Venezuela), most of them have started in their implementation; either as part of an after-sales service, or as part of the production and / or marketing process. Apparently, it only needs to be structured integrally and give it a strategic dimension.In this article processes and operations binding aspects of Zulia dairy circuit with reverse logistics are presented. In this sense, the reverse logistics in the supply chain of dairy derivatives companies in Zulia is characterized. Guide strategies and reverse logistics activities as socially responsible practices are submitted. This becomes challenging, since implementing a reverse logistics system as an essential and potential strategy is a difficult issue given the country’s socio-economic and political situation. Reflections are presented to face the barriers in retro logistics implementation. The main one being the need to internalize in each individual rational resources using and acting effectively to engage with private companies and state organizations in the sustainable institutions operations.
El concepto de logística inversa es de reciente introducción y poco conocido en las empresas del sector de derivados lácteos del estado Zulia (Venezuela), la mayoría de ellas se han iniciado en su implementación; bien como parte de un servicio postventa, o como parte del proceso de producción y/o comercialización. Aparentemente solo necesita estructurarse integralmente y darle una dimensión estratégica. En este artículo se presentan los aspectos vinculantes de los procesos y las operaciones del circuito lácteo zuliano con la logística inversa. En este sentido, se caracteriza la logística inversa en la cadena de suministro de empresas zulianas de derivados lácteos y de cómo deben orientar estrategias y actividades de logística inversa como prácticas socialmente responsables. Lo anterior se torna desafiante, pues implantar un sistema de logística inversa como estrategia esencial y potencial, es un tema aún difícil dado la coyuntura socioeconómica y política del país.En lo particular, se presentan reflexiones para afrontar las barreras en la implementación de la retrologística. Siendo la principal, la necesidad de internalizar en cada individuo el uso racional de los recursos y la necesidad de comprometerse efectivamente con las empresas y las organizaciones tanto privadas como del Estado en las operaciones sustentables de las instituciones.

Tracking ability of leveraged and inverse exchange traded funds can be very important to investors looking for a dependable return. If the investor wants to put their money on a certain index they feel strongly about, they expect their investment vehicle to track that return appropriately. Over the years, we have seen tremendous growth in the exchange traded fund industry. In 2006, leveraged and inverse funds were introduced to the market, allowing investors to take leveraged and directional trades on indices. These investment vehicles can be traded as easily as any stock, and therefore need some attention. Since any novice investor can access and trade these funds, they need to be aware of the risks they are taking. In this study, I test whether the ProShares S&P tracking leveraged and inverse exchange traded funds track their appropriate index multiple as promised. I did this by running regressions on each fund against the appropriate multiple of their underlying indices. I did this for funds of different market capitalization, for different holding periods, and with different amounts of leverage, to compare how these funds track in different conditions. I found that the large cap funds tend to track the best, with the small cap funds tracking the worst. I also find that tracking error tends to increase with longer holding periods. I find that the distribution of excess returns becomes less normal over longer holding periods, and begins to flatten out and widen. There does not seem to be a concrete conclusion as to whether or not the amount of leverage affects the tracking ability of the funds. I end up with mixed results when comparing amounts of leverage by model fit and by tracking error. Direction also does not seem to play any role in the tracking ability of these funds.
B.S.B.A.
Bachelors
Business Administration
Finance

Em radioterapia, o espectro de energia é o componente mais importante dos feixes de elétrons. Espectros de energia de elétrons são relevântes para o cálculo acurado da dose, aplicações do sistema de planejamento e simulações realistas. Reconstrução inversa consiste na derivação do espectro de energia de elétrons a partir de curvas de porcentagem de dose em profundidade utilizando um apropiado modelo matemático. Reconstrução inversa é considerada a melhor dentre muitas abordagens porque: i) não requer nenhum equipamento suplementar ou do conhecimento detalhado da geometria e composição do cabeçote do acelerador; ii) equipamentos para a medição de curvas de porcentagem de dose em profundidade estão disponíveis em qualquer clínica e iii) é computacionalmente rápida. Neste trabalho, usou-se o método de reconstrução inversa baseado na sinergia recozimento simulado generalizado-regularização de Tikhonov. A validação da reconstrução foi realizada através do índice gama sob critérios clínicos de aceitação restritivos. Resultados mostraram que os espectros de energia reconstruídos reproduzem com precisão a porcentagem de dose em profundidade clínica bem como valores de dose fora do eixo central. Assim, concluí-se que o método empregado é ecaz para reconstruir espectros de energia que representam efetivamente espectros de energia do acelerador que atingem na supercie do fantoma. Consequentemente, sob certos limites, eles poderiam auxiliar em simulações realistas do tratamento.
In radiotherapy, energy spectrum is the most critical component of any electron beam. Knowledge of energy spectrum is important for accurate dose calculation, treatment planning applications and realistic simulations. Inverse reconstruction derives energy spectrum from the measured percentage depth dose using an appropriate mathematical model. There are several advantages to using inverse reconstruction: i) it does not require any supplementary equipment or detailed knowledge of the geometry head and composition; ii) the equipment for measurement of the percentage depth dose is standard and already available in any clinic and iii) it is computationally fast. In this work, we used the inverse reconstruction method based on the synergy simulated annealing generalized-Tikhonov regularization. Validation of inverse reconstruction was done by comparing the measured and reconstructed percentage depth dose via the gamma index. Results show the reconstructed electron energy spectra accurately reproduce the clinical dose percentage as well as o-axis dose values. Therefore, it was concluded that the method employed is eective to reconstruct energy spectra that eectively represent accelerator energy spectra reaching the phantom surface. Consequently, under certain limits, they could aid in realistic simulations of treatment.

The objectives of this study were to 1) calculate participant-specific segment inertial parameters using dual energy X-ray absorptiometry (DXA) data (referred to as full DXA-driven parameters) and compare the pitching arm kinetic predictions using full DXA-driven inverse dynamics vs scaled, DXA mass-driven (using DXA masses but scaled centers of mass and radii of gyration), and DXA scaled inverse dynamics(ID) (using the full DXA-driven inertial parameters averaged across all participants), 2) examine associations between full DXA-driven kinetics and body mass index (BMI) and 3) examine associations between full DXA-driven kinetics and segment mass index (SMI). Eighteen 10- to 11- year-olds pitched 10 fastballs. DXA scans were conducted and examined to obtain 3D inertial parameters of the upper arm, forearm, and hand. Full DXA-driven and scaled inertial parameters were compared using paired t-tests. Pitching arm kinetic predictions calculated with the four methods (i.e. scaled ID, DXA mass-driven ID, full DXA-driven ID, and DXA scaled ID) were compared using a repeated measures ANOVA with Tukey post-hoc tests. The major results were that 1) full DXA-driven participant specific inertial parameters differed from scaled inertial parameters 2) kinetic predictions significantly varied by method and 3) full DXA-driven ID predictions for shoulder compression force and shoulder internal rotation torque were significantly associated with BMI and/or SMI.

Thesis (Ph. D.)--University of California, Riverside, 2009.
Includes abstract. Includes bibliographical references (leaves 107-109). Issued in print and online. Available via ProQuest Digital Dissertations.

The first essay compares six common models, linear, quadratic, Cobb-Douglas, translog, logarithmic, and transcendental, to estimate wheat yield and area functions for Saudi Arabia. Data cover 1990-2016 for all the variables that affect wheat supply. After testing the models using Box-Cox, multicollinearity, and autocorrelation tests, we decide that the Cobb-Douglas models provide the best fit for both yield and area. We find the price elasticity of wheat is inelastic. Yield price elasticities are more inelastic than area elasticities. The impact of government policy number 335 has a larger effect on area than yield. The cultivated area of wheat, the one-year lag of yield, and the number of machines per hectare are the most influential factors affecting wheat yield. The primary factors influencing the area models are a one-year lag of both cultivated area and yield, as well as the number of machines per hectare. The second essay estimates the residual demand elasticity that rice exporters face in Saudi Arabia. The inverse residual demand methods, as proposed by Reed and Saghaian 2004, are used for rice exporters to Saudi Arabia during the period 1993-2014. Estimation results of the elasticities of the residual demand indicate that Australia, India, and Pakistan enjoy market power, while Egypt faces a perfectly elastic demand curve. We find Thailand and the US had positive inverse residual demand which means they also have no market power. The last essay is about the virtual water trade in Saudi Arabia. Using the concept of virtual water introduced by Allan 1994 and developed by Hoekstra and Hung (2002), we estimate virtual water trade for 20 crops of Saudi Arabia during 2000-2016. Our result shows the average virtual water trade was 12.5 billion m3/year. Saudi has net virtual water imports, with the most significant virtual water imports coming from cereals & alfalfa and vegetables; and there is net virtual water export of fruit. Saudi virtual water trade reduces pressure on water resources by 52%. Distance plays a role in Saudi virtual water export; we found that more than 90% of exports go to neighboring countries, including 45% to GCC countries. More than 30% of virtual water imports come from Europe. A Gravity model is used to investigate whether water scarcity variables influence trade. We compare the OLS, Fixed effects, Random effects, and PPML estimators to get the best model. The AIC, and tests for multicollinearity, and heteroskedasticity assist in determining estimation procedures and the final models. We cluster the errors by distance to improve the specific country effect variables such as economic mass variables. For the cereals and alfalfa group, we find that water-related variables influence virtual water imports of cereals, millet, sorghum, corn, barley, and sesame. Therefore, we suggest that a basic gravity model be applied to the other crops. In the vegetable group, we find that related water variables impact virtual water trade for all crops except marrow. Dates are the only fruit crop that are not influenced by the water-related variables.

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As a reflex of the changes happened in the last decades in the process of globalization of the economy and of the development of the international markets, it was necessary a change in the process of generation of the accounting information in which accounting has been pressed by the demands of new markets, its potential investors and analysts to supply financial statements in an efficient and effective way for the best interpretation and decision in this market in high performance. As we insert the accounting in this globalization context, the accounting information becomes more and more relevant and of great importance in the decision process. Faced with the economic globalization of the markets, it is necessary the adoption of rules and accounting patterns globally used and accepted, allowing a comparative of the accounting information for the decisorial process. The IASB (International Accounting Standard Board) was responsible for the elaboration of international rules already in convergence process in more than 100 countries all over the world. In Brazil, with the publication of the Law number 11.638/07, being in force from January 1st, 2008, and later with the changes coming from the Law number 11.941/09, there was an important step in the process of convergence of their rules with the international patterns through the creation of the Committee of Accounting Pronouncements (CPC), responsible organ for the emission of accounting pronouncements in consonance with the International Financial Reporting Standards (IFRS). This study aims to identify the materiality of the impacts of the adoption of the International Financial Reporting Standards (IFRS) in financial statements and in companies performance, presenting the significant differences in accounts of Balance Sheet and of Incoming Statement, aiming to answer to the central question: Has the adoption of International Financial Reporting Standards (IFRS) generated impact on Equity and Profit and Loss Statement of the open capital entities listed in BOVESPA, Air Transport segment? To such purpose, it was chosen the methodology of research and of exploratory nature with descriptive studies, which provides to the researcher a larger inclusion of the occurred facts in relation to a direct research. The comparative analysis of the financial statements of the companies object of this study demonstrates that the financial statements elaborated in agreement with the International Financial Reporting Standards (IFRS) present a larger level of disclosure when compared with the old adopted pattern BR GAAP (Generally Accepted Accounting Principles). The obtained conclusion is that the process of adoption of the International Financial Reporting Standards (IFRS) has generated impacts in the Equity and Profit and Loss Statement and in several processes and controls of the companies object of this study
Como reflexo das mudanças ocorridas nas últimas décadas no processo de globalização da economia e do desenvolvimento dos mercados internacionais, fez-se necessário uma mudança no processo de geração das informações contábeis, em que a contabilidade tem sido pressionada por meio das exigências dos novos mercados, seus potenciais investidores e analistas a fornecer demonstrações contábeis de forma eficiente e eficaz para a melhor interpretação e tomada de decisões neste mercado em alta performance. Ao inserirmos a contabilidade neste contexto de globalização, a informação contábil torna-se cada vez mais relevante e de suma importância no processo decisório. Frente à globalização econômica dos mercados, faz-se necessária a adoção de normas e padrões contábeis utilizados e aceitos mundialmente, permitindo um comparativo das informações contábeis para o processo decisorial. O IASB (International Accounting Standard Board) ficou responsável pela elaboração de normas internacionais que já estão em processo de convergência em mais de 100 países em todo o mundo. No Brasil, com a publicação da Lei n.º 11.638/07, vigorando a partir de 1.º de janeiro de 2008, e, posteriormente, com as alterações emanadas da Lei n.º 11.941/09, deu-se um importante passo no processo de convergência de suas normas com os padrões internacionais por meio da criação do Comitê de Pronunciamentos Contábeis (CPC), órgão responsável pela emissão de pronunciamentos contábeis em consonância com as Normas Internacionais de Contabilidade (IFRS). O estudo tem por objetivo identificar a materialidade dos impactos da adoção das Normas Internacionais de Contabilidade (IFRS) nas demonstrações contábeis e no desempenho das empresas, apresentando as diferenças significativas em contas do Balanço Patrimonial e da Demonstração de Resultados, buscando responder à questão-problema: A adoção das Normas Internacionais de Contabilidade (IFRS) gerou impacto no Patrimônio Líquido e no Resultado do Exercício das Entidades de capital aberto listadas na BOVESPA do segmento de Transporte Aéreos? Para tanto, foi escolhida a metodologia de pesquisa de natureza exploratória com estudos descritivos, que proporciona ao pesquisador uma maior cobertura dos fatos ocorridos em relação a uma pesquisa direta. A análise comparativa das demonstrações contábeis das empresas-objeto deste estudo evidencia que as demonstrações financeiras elaboradas de acordo com os padrões IFRS apresentam um nível de divulgação maior quando comparadas com o antigo padrão adotado BR GAAP. A conclusão obtida é que o processo de adoção das Normas Internacionais de Contabilidade (IFRS) gerou impactos no Patrimônio Líquido e no Resultado do Exercício e em diversos processos e controles das empresas-objeto de estudo

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The insertion of distributed power sources of low power presents new challenges in the planning and operation of distribution systems. The coordination of the protection system is a challenge which modifies as the insertion of the distributed generation grows at any point in any system. In order to verify how the coordination is altered different indicators have been proposed in literature, seeking to express numerically the effect of this insertion on the pair of relays of a coordinated protection system. The Protection Coordination Index (PCI) and the Protection Miscoordination Index (PMI) are shown as valid indicators for this analysis. The purpose of this paper is to apply these quantifiers in the protection schemes of distribution lines of radial and grid systems that use Inverse Time Overcurrent Relays. By applying these indicators, it will be possible to judge if they will provide enough information to analyze the impact of GD insertion in the SDEE, otherwise, identify if there will be limitations which can be remedied by proposing new indicators. The new indicators proposed in this paper seek to cover the limitations observed, without necessarily using the same information. To achieve this goal, distributed generators will be connected at different points in the network, and its generation capacity will be changed in an increasing way; where for each insertion value and at each point of the system, the Coordination Time Intervals (CTI) between consecutive pairs of relays will be verified, and from these values, the quantitative indicators of the impact of the GD will be calculated. For this, a distribution grid system was modeled with a purpose of obtain the required quantities in the scaling of CT1s and relays, thus obtaining a selective coordinate operation, where for each primary relay there will be an extra relay, forming a protective pair. Next two protective systems were adjusted: one considering one-way relays and another, twoway relays. Finally, for the protection systems dimensioned and coordinated, the indexes found in the literature and the proposed indexes were calculated and compared to the same pair of relays, considering the same GD insertion value at different points of the system. Every indicator were valid to the quantification of the GD insertion impact in the protection schemes applied to SDEE, where IDP indicates a percentage of faults that will cause miscoordination, IDPP indicates the percentage of pairs of relays that will be miscoordinate for each fault, ICP shows wether the ITC variation will occur slowly or rapidly, where the faster variation will result in miscoordination rather than the slower one and ITC (%) imposes a restriction on ITC reduction indicating whether the insertion value will miscoordinate the pairs of relays analyzed through numerical values.
A inserção de fontes de energia distribuídas de baixa potência apresenta novos retos no planejamento e operação de sistemas de distribuição. Um reto é a coordenação do sistema de proteção que se altera a medida que a inserção de Geração Distribuída (GD) cresce em qualquer ponto de qualquer sistema. Para verificar como a coordenação é alterada, tem sido proposto, na literatura, diferentes indicadores que visam expressar numericamente qual é o efeito desta inserção nos pares de relés de um sistema de proteção coordenado. O Protection Coordination Index (PCI) e o Protection Miscoordination Index (PMI), se mostram como indicativos válidos para esta análise. O objetivo deste trabalho é aplicar estes quantificadores nos esquemas de proteção de linhas de distribuição de sistemas radiais e malhados que utilizem Relés de Sobrecorrente Direcionais de Tempo Inverso. Pela aplicação destes indicadores foi possível julgar se as informações obtidas são suficientes para a análise do impacto da inserção de GD nos SDEE, identificando o surgimento de limitações, sanadas pela proposição de novos indicadores. Para alcançar este objetivo, geradores distribuídos foram conectados em diferentes pontos da rede, e sua capacidade de geração foi alterada de forma crescente; onde para cada valor de inserção e em cada ponto do sistema, foram verificados os Intervalos de Tempo de Coordenação (ITC) entre pares de relés consecutivos, e a partir destes valores, os indicadores quantitativos do impacto da inserção de GD, calculados. Para isso, foi modelado um sistema de distribuição malhado, visando a obtenção das grandezas requeridas no dimensionamento dos TC's e relés, obtendo assim uma operação coordenada seletiva, onde para cada relé primário há pelo menos um de retaguarda, formando pares protetores. Em seguida dois sistemas de proteção foram ajustados: um considerando relés unidirecionais e outro, relés bidirecionais. Finalmente, para os sistemas de proteção dimensionados e coordenados, os índices encontrados na literatura e os índices propostos foram calculados e comparados para um mesmo par de relés, considerando um mesmo valor de inserção de GD em diferentes pontos do sistema. Todos os indicadores se mostraram válidos para a quantificação do impacto da inserção de GD nos esquemas de proteção aplicados a SDEE, onde IDP indica a porcentagem de faltas que irá ocasionar descoordenação, IDPP indica a porcentagem de pares de relés que irá se descoordenar para cada falta, ICP mostra se a variação de ITC ocorrerá de forma lenta ou rápida, onde a variação mais veloz resultará antes em descoordenação em relação à mais lenta e ITC (%) impõe uma restrição à redução de ITC indicando se o valor de inserção irá descoordenar os pares de relés analisados, através de valores numéricos.

Cette thèse porte sur l’étude expérimentale de l’extraction liquide-liquide au sein d’une colonne de laboratoire reproduisant de manière très simplifiée les appareils utilisés pour retraiter le combustible nucléaire (procédé hydro-métallurgique PUREX). Une technique optique non intrusive, dite de réfractométrie ou diffractométrie arc-en-ciel, a été spécifiquement développée pour caractériser la granulométrie (et donc l’aire interfaciale) et la composition de la phase dispersée. Cette dernière est composée de gouttes millimétriques de mélanges d’alcanes en ascension dans une colonne remplie d’eau au repos. Les spécificités de l’arc-en-ciel produit par ces gouttes à faible indice de réfraction relatif ont été étudiées à l’aide de différents modèles de diffusion asymptotiques de la lumière et la théorie électromagnétique de Lorenz-Mie. Grâce au développement de différentes approches directes et inverses (paramétriques), il a été démontré numériquement et expérimentalement que cette technique optique permettait d’estimer individuellement (ou collectivement) diamètre (moyen) et fraction de mélange de quelques dizaines de milliers de gouttes à quelques pour cents près. Des travaux préliminaires ont été réalisés sur l’extraction, résolue dans le temps de l’acétone, d’un milieu continu aqueux vers une goutte sessile composée initialement de toluène pur. Ils ont montré que l’on pouvait réellement estimer les constantes de transfert (de diffusion et de distribution moléculaire) à partir de l’analyse de l’évolution temporelle des arcs-en-ciel et en utilisant une méthode inverse qui intègre un modèle de diffusion moléculaire à symétrie radiale et un modèle électromagnétique ad hoc
This thesis deals with the experimental study of liquid-liquid extraction within a laboratory column reproducing in a simple way the apparatuses used in a nuclear fuel reprocessing process (PUREX). A non-intrusive optical technique, called rainbow refractometry or diffractometry, has been specifically developed to characterize the size (and hence the interfacial area) and the composition of the dispersed phase. The latter is first time composed of millimeter droplets of alkanes mixtures free rising in a column filled with water at rest. Specificities of the rainbow produced by these droplets with a low relative refractive index were studied using different asymptotic light scattering models and the Lorenz-Mie electromagnetic theory. Thanks to the development of different direct and reverse (parametric) approaches, it was demonstrated both numerically and experimentally that this optical technique allows estimating individually (or collectively) the diameter (in average) and the mixing fraction of a few tens of thousands of droplets with a few percent of accuracy. Preliminary works have been carried out on the time-resolved extraction of acetone from an aqueous continuous medium to a sessile droplet initially composed of pure toluene. They have revealed that the transfer (diffusion and molecular splitting) constants can be estimated from the analysis of the temporal evolution of the rainbow signals using an inverse method that integrates a molecular diffusion model with a radial symmetry and an electromagnetic light scattering model

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
The infiltration process understanding and its relationship with soil properties is essential for the efficient management of soil and water. Thus, this paper aimed at evaluating water infiltration in an area of Oxisol, using single ring infiltrometers with different diameters. In addition, it also aimed at comparing the performance of 7 cm (A7) and 15 cm (A15) cylinders, matching soil moisture and bulk density to water infiltration and evaluating spatial distribution of infiltration. For this purpose, 24 data points were evaluated, placed in 8 plots of a circular area prepared for permaculture cropping, named as Mandala. Shewhart graphs and process capability index were used to compare cylinders and the inverse of distance square for data interpolation. It was observed that the average stable infiltration rate, determined with A7 cylinder, was 196.79 mm h-1 and with A15 cylinder was 187.30 mm h-1, consequently, there was a difference of 5.6%. The process capacity was estimated at 0.61 for A7 and 1.62 for A15, considered adequate for A15 and inadequate for A7 cylinder. Thus, it was concluded that the infiltration rates that were stabilized and determined by the cylinders were compatible with the rates determined by other methods in other papers. Regarding the performance of single-ring infiltrometers, it is concluded that, although both cylinders presented controlled processes, and did not differ statistically, cylinder A15 presented less variability on data, and may be considered adequate due to its process capability index.
O entendimento do processo de infiltração e das suas relações com as propriedades do solo é fundamental para o eficiente manejo do solo e da água. Assim, este trabalho teve como objetivo avaliar a infiltração de água em uma área de latossolo vermelho, para tanto, foram utilizados infiltrômetros de único cilindro, de diferentes diâmetros. Além disso, objetivou-se comparar o desempenho desses cilindros de 7 (A7) e de 15 cm (A15), relacionar a umidade e a densidade aparente do solo à infiltração da água e avaliar a distribuição espacial da infiltração. Foram avaliados 24 pontos de coleta de dados, alocados em 8 parcelas de um talhão circular preparado para plantio em regime de permacultura, denominado mandala. Gráficos de Shewhart e o índice de capacidade de processo foram utilizados para a comparação entre os cilindros e inverso do quadrado da distância para interpolação de dados. Verificou-se que a taxa de infiltração estável média, determinada com o cilindro A7, foi de 196,79 mm h-1 e com o cilindro A15 foi de 187,30 mm h-1, cuja diferença foi de 5,6 %. A capacidade de processo foi estimada em 0,61 para A7 e 1,62 para A15, a qual foi considerada adequada para o cilindro A15, porém inadequada para cilindro A7. Desta forma, neste trabalho, concluiu-se que as taxas de infiltração estáveis e determinadas pelos cilindros foram compatíveis com as taxas determinadas por outros métodos em outros trabalhos. Em relação ao desempenho dos infiltrômetros de cilindros únicos, conclui-se que, embora ambos os cilindros tenham apresentado processos controlados e não tenham diferido estatisticamente, o cilindro A15 apresentou menos variabilidade dos dados, e pode ser considerado adequado em função do seu índice de capacidade de processo.

This diplome thesisdeals with determining of investment project economic efficiency. Evaluated investment project is redevelopment of urban house into boarding house with restaurant and café. The project is analyzed both in terms of pre-investment phase and 6 years after completion or reconstruction.  There is comparison of both analysis at the end of dissertation including optimal solution suggestion of current situation.

Dans cette thèse, nous étudions le problème de réduction de la dimension dans le cadre du modèle de régression suivant Y=g(B X,e), où X est un vecteur de dimension p, Y appartient à R, la fonction g est inconnue et le bruit e est indépendant de X. Nous nous intéressons à l'estimation de la matrice B, de taille dxp où d est plus petit que p, (dont la connaissance permet d'obtenir de bonnes vitesses de convergence pour l'estimation de g). Ce problème est traité en utilisant deux approches distinctes. La première, appelée régression inverse nécessite la condition de linéarité sur X. La seconde, appelée semi-paramétrique ne requiert pas une telle condition mais seulement que X possède une densité lisse. Dans le cadre de la régression inverse, nous étudions deux familles de méthodes respectivement basées sur E[X f(Y)] et E[XX^T f(Y)]. Pour chacune de ces familles, nous obtenons les conditions sur f permettant une estimation exhaustive de B, aussi nous calculons la fonction f optimale par minimisation de la variance asymptotique. Dans le cadre de l'approche semi-paramétrique, nous proposons une méthode permettant l'estimation du gradient de la fonction de régression. Sous des hypothèses semi-paramétriques classiques, nous montrons la normalité asymptotique de notre estimateur et l'exhaustivité de l'estimation de B. Quel que soit l'approche considérée, une question fondamentale est soulevée : comment choisir la dimension de B ? Pour cela, nous proposons une méthode d'estimation du rang d'une matrice par test d'hypothèse bootstrap.

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CAPEs
Este trabalho descreve a operação e desempenho de um sistema fotovoltaico ligado à rede, alocado em um escritório comercial na cidade de Maceió, Alagoas. O gerador é composto por três subsistemas independentes, totalizando potência total de 1,6 kWp e conectada à rede elétrica local. Os subsistemas são compostos por tecnologias comerciais: Si-p e Si-m, permitindo a avaliação do desempenho operacional dessas tecnologias na condição de clima tropical marítimo. Para realizar a análise, o sistema foi particionado em três subsistemas distintos, onde inicialmente os subsistemas I e II operavam com um fator de dimensionamento de 1,42 e o subsistema III com um fator de 0,98. Cada arranjo dos geradores do subsistema I e II opera com quatro módulos de 140 Wp totalizando uma potência total de 560 Wp, sendo as células de silício policristalino e monocristalino, respectivamente. O subsistema III possui quatro módulos de 130 Wp, de silício policristalino totalizando 520 Wp. Para as tecnologias comerciais estudadas nos subsistemas I, II e III, sob as mesmas variabilidades climatológicas (irradiância, temperatura ambiente e velocidade do vento), condições padrão de instalação elétrica, FDI e inversores idênticos (800 W) os subsistemas I e II obtiveram os mesmo níveis de eficiência de conversão fotovoltaica máxima (13%), produtividade mensal média (145 kWh/kWp), coeficientes de desempenho bem próximos (78%). A eficiência de conversão, CCCA, para os inversores que estavam com FDI igual a 1,42, (subsistemas I e II) mostrou-se uma boa eficiência em toda a faixa de operação, entre 89 – 94%. Em contrapartida, o inversor que estava operando com um FDI igual a 0,87 (subsistema III), provou-se menos eficiente, tendo uma eficiência em torno de 81%. O desempenho operacional do seguidor do ponto de máxima potência mostrou-se ineficiente, porque o arranjo fotovoltaico estava trabalhando com tensão fixa em quase todo o tempo de operação.
This paper describes the operation and performance of a photovoltaic system connected to the network allocated on a commercial office in the city of Maceió, Alagoas. The generator consists of three independent subsystems, adding up of 1.6 kWp output installed and connected to the local power grid. The subsystems consist of commercial technologies: p-Si and m-Si, allowing the evaluation of the operating performance of these technologies in the maritime tropical climate condition. To perform the analysis the system has been partitioned into three distinct subsystems which initially subsystems I and II operated with a scale factor of 1.42 and subsystem III with a factor of 0.98. Each arrangement subsystems I and II operates four modules of 140 Wp adding up a total output of 560 Wp, using cells polycrystalline and monocrystalline silicon, respectively. The subsystem III has four modules of 130 Wp polycrystalline silicon with a total of 520 Wp. For commercial technologies studied the subsystems I, II and III under the same climate variability (irradiance ambient temperature, wind speed) electrical standard conditions, FDI and inverters (800 W), subsystems I and II obtained the same level of maximum photovoltaic efficiency conversion (13%), average monthly productivity (145 kWh / kWp), coefficient of performance (78%). The conversion efficiency, DC-AC, for inversors with FDI 1.42 (subsystems I and II) had a good efficiency across the operating rate, between 89-94%. However, the inverter were operating with a FDI equal 0.87 (subsystem III), was less efficient, having an efficiency around 81%. The operating performance at the point of maximum power proved to be inefficient, because the PV system array was working with fixed voltage for almost all operating time.

The purposes of this study are to investigate the possible effects of variables like testing depth, length to diameter ratio of the probe, presence of disturbed annulus around the borehole etc. on the derived parameters from the pressuremeter test, and to develop possible alternative methods for the determination of undrained shear strength of cohesive soils, and cohesion and internal friction angle of intermediate geomaterials. For this purpose numerical simulations of pressuremeter test were performed. In the study, it is also aimed to investigate the effect of rock quality designation (RQD) or some other rock mass parameters such as geological strength index (GSI) and rock mass rating (RMR) and intact rock strength on the deformation modulus determined from the pressuremeter test. To accomplish this task, Dikmen greywackes, weathered andesites and mudrocks exposed around Ankara - Sincan region were selected for field and laboratory studies. Empirical relationships using GSI, RMR, RQD were developed for the estimation of deformation modulus of greywackes and mudrocks cropping out around Ankara. Numerical simulations revealed the presence of disturbed annulus around the borehole causes underestimation of deformation modulus and overestimation of undrained shear strength. Test depth has no effect on the deformation modulus and undrained shear strength
the effect of length to diameter ratio of the probe on the deformation modulus is minor where as it causes overestimations of undrained shear strength. Pore pressure dissipation in low permeability soils around the pressuremeter was studied using numerical simulations. These analyses suggest that for permeabilities lower that 10-10 m/sec there is no pore pressure dissipation around the pressuremeter probe. It was determined that the inverse analysis yielded successful results for the determination of shear strength parameters of intermediate geomaterials.

[EN] The aim of this work is to demonstrate theoretically and experimentally how acoustic wave propagation can be controlled by temperature gradients. Starting with the simplest case of two hot wires in air the study extends over periodic structures known as Sonic Crystals (SCs). The Finite Elements Method (FEM) has been employed to perform numerical simulations in order to demonstrate collimation and focusing effect of acoustic waves in two-dimensional (2D) SC whose filling fraction is adjusted by temperature gradients. As a part of the research, Bragg reflection and Fabry-Perot type of acoustic effects are investigated for the proposed type of SC. As example, a SC with desired transmittance can be tailored. Also, gradient index (GRIN) 2D sonic lenses are studied. Using parallel rows of heated wires whose temperatures vary according to a prefixed gradient index law a GRIN lens can be designed with a given performance. Moreover, by changing the temperature of the wires a change in the filling fraction inside the GRIN SC can be achieved. Thus, the local refraction index, which is directly related to the filling fraction, is changed too and an index gradient variation inside the GRIN SC is obtained. This GRIN SC is a direct analogy of gradient media observed in nature. Like their optical counterparts, the investigated 2D GRIN SC lenses have flat surfaces and are easier for fabrication than curved SC lenses. The bending of sound waves obtained by GRIN acoustics structures can be used to focusing and collimating acoustic waves. Another aspect of this work is about tuning some SC properties as effective refractive index, effective mass density, etc. in order to obtain a SC with prefixed properties. Since active tuning of the phononic band gaps is certainly desirable for future applications with enhanced functionalities, few attempts have been made to develop tunable SCs thus far. By controlling the incident angle or operating frequency, a GRIN SC can dynamically adjust the curved trajectory of acoustic wave propagation inside the SC structure. Among the last studies of tunable SCs, the filling fractions were tuned either by direct physical deformation of the structure or external stimuli. The former is impractical for most applications and the latter often requires very strong stimuli to produce only modest adjustment. In this work another way to tune the SC properties is proposed. Hot and cold media have different density, speed of sound, refractive index, etc. in comparison with the same properties at normal conditions, so inserting temperature gradients inside the medium can be used to tune the SC properties in certain limits. The proposed way to obtain temperature gradients inside SC is by wires made of Nicrom which are heated by electrical currents. There are some important advantages of this method. First, changing the electrical current intensity through the wires the SC properties can be changed dynamically. Second, it is relatively easier to change the filling fraction simply by adjusting the current intensity than physically changing the structure or applying strong electric or magnetic fields. In conclusion, the method proposed in this thesis allows us, in principle, to get materials and structures with dynamically adjustable acoustic properties using the temperature control through electric current in the wires, within certain limits. Thus, it is easy to carry out experiments of wave propagation phenomena in a macroscopic scale similar to those that occur in microscopic structures for the propagation of electromagnetic waves of high frequency (microwaves and light).
[ES] El objetivo de este trabajo es demostrar teoréticamente y experimentalmente como la propagación de ondas acústicas puede ser controlada por gradientes de temperatura. Empezando con el caso más simple de dos hilos calientes en aire, el estudio se extiende sobre estructuras periódicas conocidas como cristales sónicos (CS). Se ha utilizado el Método de Elementos Finitos (FEM) para realizar simulaciones numéricas con el objetivo de demonstrar la colimación y focalización de ondas acústicas en CS bidimensionales (2D) cuya fracción de llenado es ajustable mediante gradientes de temperatura. Como parte de la investigación se ha analizado la reflexión de Bragg y el efecto de tipo Fabry-Perot asociados con los CSs estudiados. Entre los ejemplos tratados figuran un CS con una transmitancia ajustable a voluntad, dentro de ciertos límites. También se han estudiado lentes acústicas bidimensionales de gradiente de índice, basadas en gradiente de temperatura. Utilizando cortinas paralelas de hilos calientes cuya temperatura varía según una ley dada se puede diseñar una lente GRIN con propiedades determinadas. Por otra parte, cambiando la temperatura de los hilos se puede lograr un cambio en la fracción de llenado dentro del GRIN CS. Así, el índice de refracción local, que está directamente relacionado con la fracción de llenado, se cambia también y se obtiene una variación de gradiente de índice dentro del GRIN CS. Este GRIN CS es una analogía directa de medios con gradiente, observados en la naturaleza. Otro aspecto de este trabajo trata sobre el ajuste de algunas propiedades de un SC como el índice de refracción efectivo o la densidad efectiva con el objetivo de obtener unas propiedades deseadas del cristal. Como el ajuste activo de los bandgaps fonónicos es ciertamente deseado para futuras aplicaciones con funcionalidades mejoradas, hasta ahora se han hecho varios intentos de desarrollar CSs de características ajustables. Controlando el ángulo de incidencia o la frecuencia de funcionamiento, un GRIN CS puede ajustar dinámicamente la curvatura de la trayectoria de propagación dentro de la estructura CS. Entre los últimos estudios de CSs las fracciones de llenado se ajustaron mediante una deformación física directa de la estructura o mediante estímulos externos (por ejemplo campos eléctricos o magnéticos). El primero es poco práctico para una gran parte de las aplicaciones y el segundo a menudo requiere estímulos muy fuertes para ajustes modestos. En este trabajo se propone otra forma de ajustar las propiedades de un CS. Las propiedades acústicas del medio de propagación (densidad, índice de refracción) dependen de la temperatura, por tanto, introduciendo gradientes de temperatura dentro de dicho medio pueden ajustarse a voluntad las propiedades del CS dentro de ciertos límites. La manera de obtener gradientes de temperatura dentro del CS, propuesta en este estudio, es mediante hilos de nicrom calentados con corrientes eléctricas. Hay algunas ventajas importantes de este método. En primer lugar, cambiando la intensidad de corriente eléctrica que circula por los hilos se puede conseguir cambiar dinámicamente las propiedades del CS. En segundo lugar, es relativamente más fácil de cambiar la fracción de llenado simplemente ajustando la intensidad de la corriente eléctrica que modificar físicamente la estructura o aplicar fuertes campos eléctricos o magnéticos. En conclusión, el método propuesto en esta tesis permite, en principio, conseguir materiales y estructuras con propiedades acústicas ajustables dinámicamente mediante el control de la temperatura a través de la corriente eléctrica en los hilos, dentro de ciertos límites. De esta forma se puede experimentar fácilmente a escala macroscópica fenómenos de propagación de ondas análogos a los que ocurren en estructuras microscópicas para la propagación de ondas electromagnéticas de alta frecuencia (microondas y l
[CAT] L'objectiu d'este treball és demostrar teorèticament i experimentalment com la propagació d'ones acústiques pot ser controlada per gradients de temperatura. Començant amb el cas més simple de dos fils calents en aire, l'estudi s'estén sobre estructures periòdiques conegudes com a cristalls sónics (CS) . S'ha utilitzat el Mètode d'Elements Finits (FEM) per a realitzar simulacions numèriques amb l'objectiu de demonstrar la col¿limació i focalització d'ones acústiques en CS bidimensionals (2D) la fracció de omplit de la qual és ajustable per mitjà de gradients de temperatura. Com a part de la investigació s'ha analitzat la reflexió de Bragg i l'efecte de tipus Fabry-Perot associats amb els CSs estudiats. Entre els exemples tractats figuren un CS amb una transmitancia ajustable a voluntat, dins de certs límits. També s'han estudiat lents acústiques bidimensionals de gradient d'índex, basades en gradient de temperatura. Utilitzant cortines paral¿leles de fils calents la temperatura de la qual varia segons una llei donada es pot dissenyar una lent GRIN amb propietats determinades. D'altra banda, canviant la temperatura dels fils es pot aconseguir un canvi en la fracció d'ompliment dins del GRIN CS. Així, l'índex de refracció local, que està directament relacionat amb la fracció d'ompliment, es canvia també i s'obté una variació de gradient d'índex dins del GRIN CS. Este GRIN CS és una analogia directa de mitjans amb gradient, observats en la naturalesa. Com les seues analogies òptiques, les lents, estudiades en este treball, tenen les superfícies planes i són més fàcils de fabricar que les lents corbades. La deflexión de les ones acústiques obtinguda per mitjà d'una lent de gradient GRIN es pot utilitzar per a focalitzar o colimar feixos de so. Un altre aspecte d'este treball tracta sobre l'ajust d'algunes propietats d'un SC com l'índex de refracció efectiu o la densitat efectiva amb l'objectiu d'obtindre unes propietats desitjades del cristall. Com l'ajust actiu dels bandgaps fonónicos és certament desitjat per a futures aplicacions amb funcionalitats millorades, fins ara s'han fet diversos intents de desenrotllar CSs de característiques ajustables. Controlant l'angle d'incidència o la freqüència de funcionament, un GRIN CS pot ajustar dinàmicament la curvatura de la trajectòria de propagació dins de l'estructura CS. Entre els últims estudis de CSs les fraccions d'ompliment es van ajustar per mitjà d'una deformació física directa de l'estructura o per mitjà d'estímuls externs. El primer és poc pràctic per a una gran part de les aplicacions i el segon sovint requerix estímuls molt forts per a ajustos modestos. En este treball es proposa una altra forma d'ajustar les propietats d'un CS. Les propietats acústiques del mig de propagació (densitat, índex de refracció) depenen de la temperatura, per tant, introduint gradients de temperatura dins del dit mitjà poden ajustar-se a voluntat les propietats del CS dins de certs límits. La manera d'obtindre gradients de temperatura dins del CS, proposta en este estudi, és per mitjà de fils de Nicrom calfats amb corrents elèctrics. Hi ha alguns avantatges importants d'este mètode. En primer lloc, canviant la intensitat de corrent elèctric que circula pels fils es pot aconseguir canviar dinàmicament les propietats del CS. En segon lloc, és relativament més fàcil de canviar la fracció d'ompliment simplement ajustant la intensitat del corrent elèctric que modificar físicament l'estructura o aplicar forts camps elèctrics o magnètics. En conclusió, el mètode proposat en esta tesi permet, en principi, aconseguir materials i estructures amb propietats acústiques ajustables dinàmicament per mitjà del control de la temperatura a través del corrent elèctric en els fils, dins de certs límits. D'esta manera es pot experimentar fàcilment a escala macroscòpica fenòmens de propagació d'ones anàlegs a què ocorren e
Ivanov Angelov, M. (2016). Sound Scattering by Lattices of Heated Wires [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/63275
TESIS

The goal of this master thesis is creation of an online system serving as a performing application for presentation results of visual geo-localization in nature and mountain environment. The system offers the users to choose one of the pre-defined photographs or~to~upload one's own photography while choosing a file or inserting an URL address. The~system will localizate a camera of a given image based on a visual geo-localization. The~geo-localization uses the mountain horizon as a key characteristic when searching for similar horizons. The~curve line of the horizon is extracted by a fully automatic algorithm based on supervised learning and dynamic programming. Visual geo-localization running on the server which using new inversed index with cache politic. This allows further scaling of the system. The server processing detected horizon curve and respond with set of the best candidates on results. Results are visualised to the user in form of classic map, detailed sattelite view and rendering of found panorama.

碩士
致遠管理學院
觀光資源與環境學系碩士班
97
Environment Protection Agency(EPA) spilt Taiwan into 7 air quality control areas to provide related information. However, the more detail information at specific location is remained unknown. In order to provide more detail air quality information, we use geostatisrtical method to estimate air pollutant concentrations around the island by using the air pollutant monitoring data provided by EPA. In order to monitor air quality, EPA set up air quality monitoring network to measure concentration of 5 indicating air pollutants which includes Carbon Monoxide(CO), Nitrogen Dioxide(NO2),Sulfur Dioxide(SO2), Ozone(O3) and Particulate Matter(PM10).The collected point concentration data were interpolated into surface by using Inverse Distance Weight method. Cross validation was needed to test the accuracy of the predicted concentrations. The concentration surfaces were converted to Pollution Standards Index(PSI) according to the concentration to PSI standard provided by EPA. The final PSI then provides as detail in formation for Taiwan air quality. Key words : air quality , geostatistical method, pollutant standards index

碩士
銘傳大學
財務金融學系碩士在職專班
101
The aim of this research is to probe into if there are asymmetric effects and inverse phenomena occurred in Taiwan index option of our Future Exchange Market. The essay utilizes Option implied volatility concept to examine the existence of linear relationships between the volatility effects of both current and prior periods in the implied volatility conditions variation equation. The approach in this essay is from VS-GARCH Model to assess whether there are asymmetric effects and inverse phenomena under the impacts of either positive or negative market information. As the empirical experiments reveal, via data stationary test and sign bias test, the VS-GARCH model confirms that Taiwan index option market possesses the asymmetric effects and inverse phenomena. Furthermore, the trading strategy of buying put option in bear market substantiates extra huge amount of profit caused by asymmetric effects, which is far better in trading performance than the selling the call option in bull market. Moreover, using timeline as X axis to ascertains the signals of the inverse phenomena during the test period in the Taiwan index option of Future Market. And the empirical practices corroborate this research.

碩士
佛光大學
應用經濟學系
105
In recent years,under the leadership and support of the Financial Supervisory Commission,the Stock Exchange and lnvest and Consulting Business have developed various new commodities and related systems the ETF. Investors are provided with diversified financial products and high-quality investment environment. ETF has many advantages,such as exchange traded on market, tracking index,diversification of risk and low cost. Since the first ETF in 2003,there has been many kind of commodities available in the market. And the presentation of leveraged and reverse ETF in 2014,investors are brought to a new rea of trading commodities from the previous form of "buy and hold". Now investors can construct a diversified investment strategy, freely adjustment the trading components and in return given a better efficiency of using funds. The main purpose of this article is to explore the relation between the reverse ETF price index, broader market index and the large index. And to find a stable profit method. This study collected data of 328 days from December 1 st 2015 to April 14, 2017;as well as data of 598 days from October 31, 2014 to April 14, 2017 to do the relevance analysis of the performance. The method is used to verify whether there was a long-term equilibrium relationship between variables, and by using of the VECM model to test the short-term dynamic adiudtment and causality of varables. Finally, the performance analysis was calculated by the cobweb trading pattern. The empirical results show that the reverse ETF stock price index, the broader market index and the large platform index are randomly ordered. It becomes stable after the first difference. By using of the cointegration and error correction model of Johansen, it is found that there is a long-term equilibrium relationship between the reverse ETF stock price index, the broader market index and the large index, and the reverse ETF stock price index is inversely related to the broader market index and the large index. In addition, the consequence shows that there is a cause and effect relationship between the broader market index and reverse ETFstock price index. Same situation also exists between the large index and reverse ETF stock price index. And finally, through the the cobweb transaction model, the effect of profit and diversification of rick can be achieved.

碩士
逢甲大學
金融碩士在職專班
104
This thesis studies the index tracking performance of the two exchange-traded funds (Yuanta/P-shares Taiwan Top 50 ETF and Proshare S&P 500), the two leveraged ETFS (Yuanta Daily Taiwan 50 Bull 2X ETF and Ultra S&P 500), and the two reverse ETFS (Yuanta Daily Taiwan 50 Bear -1X ETF and Short S&P 500). The data used is the daily returns from November 3, 2014 to January 29, 2016. The estimated slopes, the R-squared and the residual standard errors of simple linear regression models are used for the performance measurement. The empirical results show the ETFs, the leveraged ETFs and the reverse ETFs of S&P 500 have better tracking performances than those of ETFs in Taiwan. According to the estimated slopes, on average, when the underlying index is up one percent, the S&P500 ETF up 0.99%, but the Taiwan Top 50 ETF is only up 0.89%; The Ultra S&P500 ETF is up 1.99%, but the Taiwan 50 Bull 2X ETF is only up 1.68%; The Short S&P500 ETF is down -1% while the Taiwan 50 Bear -1X ETF is only down -0.81%.

碩士
國立彰化師範大學
財務金融技術學系
104
This study uses employee compensation as a benchmark and employs Taiwan High Compensation 100 Index as Corporate Social Responsibility proxy. The study focuses on examing the relationship between CSR investment index and financial performance. The samples include High Compensation 100 and non High Compensation 100, and financial data are from Taiwan Economic Journal during 2014 to 2015. The empirical result shows that the relationship between CSR investment index and financial performance is negative. Besides, the result shows the greater ROE、EPS、Tobins Q the companies have, the higher the probability to enter High Compensation 100. Furthermore, the companies with higher EBITDA are willing to increase personnel expenses.

Photodynamic therapy (PDT) derives its tumour selectivity from preferential photosensitizer accumulation and short light penetration in tissue. However, additional strategies are needed to improve the therapeutic index of PDT in oncological applications where light is delivered interstitially to large volumes (e.g. prostate), or when adjacent normal tissue is extremely sensitive (e.g. brain). Much research to improve PDT's selectivity is directed towards developing targeted photosensitizers. Here, I present two alternative strategies to improve PDT's selectivity, without compromising its efficacy. For interstitial delivery, I investigated whether customizable cylindrical diffusers can be used to deliver light doses that conform better to target geometries, specifically the prostate. Additionally, I examined whether the neuroprotectant erythropoietin, used as an adjuvant to PDT for brain tumours, can reduce the sensitivity of normal tissue, thereby improving treatment selectivity. To determine if tailored diffusers constitute an improvement over conventional ones, I introduce a novel optimization algorithm for treatment planning. I also analyze the sensitivity of the resulting plans to changes in the optical properties and diffuser placement. These results are contextualized by a mathematical formalism to characterize the light dose distributions arising from tailored diffusers. In parallel, I investigate the neuroprotective effects of erythropoietin in PDT of primary cortical neurons in culture and normal rat brain in vivo. I show that the most important parameter determining prostate coverage is the number of diffusers employed. Moreover, while tailored diffusers do offer an improvement over conventional ones, the improvement is likely masked by perturbations introduced by the uncertainties of light delivery. Although these results largely discard the use of tailored diffusers in prostate PDT, significant insight has been gained into PDT treatment planning, and tailored diffusers may still be advantageous in more complicated geometries. Additionally, I show that erythropoietin does not improve survival of PDT-treated neurons PDT, nor reduces the volume of necrosis in vivo, for the ranges of conditions and doses studied. To our knowledge, this is the first time this strategy has been tested in brain PDT and deserves to be investigated further, by using later time-points, functional outcomes, and other neuroprotectants.

碩士
輔仁大學
應用統計學研究所
94
In addition to represent the price for construction materials and labors, Construction Cost Index (CCI) provides with the function to adjust outlays for constructions in progress. Forecasting for price trend of construction materials and labors provides information not only for government organizations to evaluate reasonableness of outlays of public constructions, but also for small and medium construction firms to measure profit of constructions. Although CCI is a key indicator for construction cost and government organizations, the authoritative forecasting for CCI is deficient. To this end, the study integrate Gene Algorithm(GA) and invert model analysis which is in common use for security markets to develop methodology for forecasting CCI trend and reverse point by application of Microsoft Excel extra gene algorithm module-Evolver. Due to lack original transaction data, the study adopts the price and weight data from January 2001 to October 2005 for 106 construction material and labor items proclaimed by Directorate-General of Budget, Accounting and Statistics. To develop the forecasting methodology, the study follows the several steps including diminishing the range of items from 106 items to 14 common use items, setting computing rules and limitation terms for gene algorithm, building index computing models, computing trend baseline of CCI, building interval of trend baseline of CCI. The result, that error of CCI between 106 items and 14 items is within 4.83%, shows that the methodology is helpful to simplify collecting data and computing index. Without the difficulty of gene algorithm, application of Evolver is so easy to use that the cost of forecasting is very low and suit for small and medium construction firms. Besides, the methodology can be applied to fit forecasting needs in other fields by modifying price items and parameters.

碩士
佛光人文社會學院
管理學研究所
92
Stock market is one of the channel for corporate to raise capital. As for an high economic growth country, no matter how government, enterprise, or individual activities always pass through efficiency money market to collect capital, to reduce using cost for capital demand, and to raise the efficiency of capital. Stock market is an earlier and more complete capital market in Taiwan. During the high conscious of investing today and with multiplicity of investment commodity, investors hope to seek a best timing of invest-in on the stock market. To obtain an excess return under high risk and high return on the surge and changing fast of stock market, this study proposes one set of technical analysis to find a best timing of invest-in. The objective of this study focus on the examine of invest-in timing on the stock market with technical analysis index and try to obtain follows: ․examining the interaction relation among the index of RSI, MACD, and DIF on the stock market. ․trying to find different combinations after clear understanding the interaction among the afore-mentioned index. ․comparing the gain and revenue among different combinations and then find its best timing of invest-in. Using daily closing price of TAIEX, Taiwan Stock Exchange Corporation as data sources, the samples are composed by 6-day index of RSI, MACD, DIF, and D-M. Time period of this study covered 1548 days, it is from January 4, 1997 to June 30, 2003. Research method of this study is to find the best timing of invest-in by the local and global minimum of technical analysis index and stock price based on the wave cycle of TAIEX. Empirical results of this study: 1. From 1997 to June 30, 2003，it obtained the best time of invest-in for the first model as follows: (1) Twice of invest-in points during 1997 (September 15 and October 29) (2) No invest-in point during 1998 (3) Four points of invest-in during 1999 (January 5 and 25, August 6, and October 22) (4) Four points of invest-in during 2000 (March 6, May 3 and 11, and September 22) (5) No invest-in point during 2001 (6) Three points of invest-in during 2002 (May 21, June 12, and July 29) (7) Once of invest-in during 2003 (February 27) 2. First model refers to A > A’, B < B’, and C < C’. Comparing among seven models proposed by the study, the first model is the least risk and the highest return. The success rate of the first model is 97.62﹪.

Meteorological drought indices are commonly calculated from climatic stations that have long-term historical data and then converted to a regular grid using spatial interpolation methods. The gridded drought indices are mapped to aid decision making by policy makers and the general public. This study analyzes the spatial performance of interpolation methods for meteorological drought indices in the United States based on data from the Co-operative Observer Network (COOP) and United States Historical Climatology Network (USHCN) for different months, climatic regions and years. An error analysis was performed using cross-validation and the results were compared for the 9 climate regions that comprise the United States. Errors are generally higher in regions and months dominated by convective precipitation. Errors are also higher in regions like the western United States that are dominated by mountainous terrain. Higher errors are consistently observed in the southeastern U.S. especially in Florida. Interpolation errors are generally higher in the summer than winter. The accuracy of different drought indices was also compared. The Standardized Precipitation and Evapotranspiration Index (SPEI) tends to have lower errors than Standardized Precipitation Index (SPI) in seasons with significant convective precipitation. This is likely because SPEI uses both precipitation and temperature data in its calculation, whereas SPI is based solely on precipitation. There are also variations in interpolation accuracy based on the network that is used. In general, COOP is more accurate than USHCN because the COOP network has a higher density of stations. USHCN is a subset of the COOP network that is comprised of high quality stations that have a long and complete record. However the difference in accuracy is not as significant as the difference in spatial density between the two networks. For multiscalar SPI, USHCN performs better than COOP because the stations tend to have a longer record. The ordinary kriging method (with optimal function fitting) performed better than Inverse Distance Weighted (IDW) methods (power parameters 2.0 and 2.5) in all cases and therefore it is recommended for interpolating drought indices. However, ordinary kriging only provided a statistically significant improvement in accuracy for the Palmer Drought Severity Index (PDSI) with the COOP network. Therefore it can be concluded that IDW is a reasonable method for interpolating drought indices, but optimal ordinary kriging provides some improvement in accuracy. The most significant factor affecting the spatial accuracy of drought indices is seasonality (precipitation climatology) and this holds true for almost all the regions of U.S. for 1-month SPI and SPEI. The high-quality USHCN network gives better interpolation accuracy with 6-, 9- and 12-month SPI and variation in errors amongst the different SPI time scales is minimal. The difference between networks is also significant for PDSI. Although the absolute magnitude of the differences between interpolation with COOP and USHCN are small, the accuracy of interpolation with COOP is much more spatially variable than with USHCN.

Orthogonal frequency division multiplexing (OFDM) is a multicarrier transmission technique which provides efficient bandwidth utilization and robustness against time dis¬persive channels. A major problem in the RF portion of a multicarrier transmitter is Gaussian-like time-domain signals with relatively high peak-to-average power ratios (PA¬PRs). These peaks can lead to saturation in the power amplifier (PA) which in turn distorts the signal and reduces the PA efficiency. To address this problem, numerous techniques have appeared in the literature based on signal and/or data modification. In the class of distortionless techniques, partial transmit sequences (PTS), selective mapping (SLM), and tone reservation (TR) have received a great deal of attention as they are proven techniques that achieve significant PAPR reduction. However, high compu¬tational complexity is a problem in practical systems. In PTS and SLM, this complexity arises from the computation of multiple inverse fast Fourier transforms (IFFTs), resulting in a complexity proportional to the number of PTS subblocks or SLM sequences. TR has also a high computational complexity related to the computation of the IFFT as it must search for the optimal subsets of reserved subcarriers and generate the peak reduction signal. In addition, most research in the direction of analyzing and improving the above techniques has employed direct computation of the inverse discrete Fourier transform (IDFT), which is not practical for implementation. This thesis focuses on the development and performance analysis of the major distortionless techniques in conjunction with the common IFFT algorithms to reduce the peak-to-power average (PAPR) of the original OFDM signal at the transmitter side. The structure of the IFFT common algorithms is used to propose a class of IFFT-based PAPR reduction techniques to reduce the computational complexity and improve PAPR performance. For IFFT based PTS, two techniques are proposed. A low complexity scheme based on decimation in frequency (DIF) and high radix IFFT algorithm is proposed. Then, a new PTS subblocking technique is proposed to improve PAPR performance. The periodic auto-correlation function (ACF) of time-domain IFFT-based PTS subblocks is derived. To improve the PAPR, we use error-correcting codes (ECCs) in the subblocking. Our approach significantly decreases the computational complexity while providing comparable PAPR reduction to ordinary PTS (O-PTS). With IFFT-based SLM, a technique for reducing computational complexity is proposed. This technique is based on multiplying the phase sequences with a subset of the inputs to identical inverse discrete Fourier transform (IDFTs). These subsets generate the partial SLM sequences using repetition codes. It is also shown how the partial time-domain sub-sets can be combined to generate new SLM sequences. These sequences do not requires any IFFT operations. The proposed scheme outperforms the existing techniques while pro¬viding comparable PAPR reduction to original SLM (O-SLM). Finally, a gradient-based algorithm is proposed for IFFT-based TR. Unlike previous work, non-static channels are considered where the peak reduction tones (PRTs) locations and consequently the peak reduction kernels should be adjusted dynamically for best per¬formance. Two low complexity algorithms with different degrees of computational com¬plexity and PAPR performance are proposed. To generate the peak reduction kernels, the transform matrices of identical IFFTs are used. This provides low complexity solutions to determining the PRTs and computing the peak reduction kernels.

Σε έναν κόσμο που κατακλύζεται από δεδομένα, καθίσταται αναγκαία η αποδοτική οργάνωσή τους και η μετέπειτα επεξεργασία τους, με σκοπό την εύρεση και την ανάκτηση πληροφορίας για λήψη αποφάσεων. Στα πλαίσια της προσπάθειας αυτής έχουν δημοσιευθεί διάφορες μελέτες που στοχεύουν στην ανεύρεση σχέσεων μεταξύ των δεδομένων, οι οποίες μπορούν να αναδείξουν άγνωστες μέχρι πρότινος εξαρτήσεις και να επιτρέψουν την πρόγνωση και την πρόβλεψη μελλοντικών αποτελεσμάτων και αποφάσεων. Στην εργασία αυτή μελετάμε τους πιο διαδεδομένους αλγορίθμους εύρεσης κανόνων συσχετίσεων και ακολούθως προτείνουμε ένα σχήμα που χρησιμοποιεί ως βασική δομή για την ανάκτηση πληροφορίας από βάσεις δεδομένων συναλλαγών τα αντεστραμμένα αρχεία. Στόχος μας είναι η εύκολη παραγωγή κανόνων συσχέτισης αντικειμένων, βασιζόμενη στην αποδοτική αποθήκευση και ανάκτηση των Συχνών Συνόλων Αντικειμένων (Frequent Itemsets). Αρχικά επικεντρωνόμαστε στον τρόπο εύρεσης και αποθήκευσης ενός ελάχιστου συνόλου συναλλαγών, εκμεταλλευόμενοι την πληροφορία που εμπεριέχουν τα Κλειστά Συχνά Σύνολα Αντικειμένων (Closed Frequent Itemsets) και τα Μέγιστα Συχνά Σύνολα Αντικειμένων (Maximum Frequent Itemsets). Στη συνέχεια, αξιοποιώντας την αποθηκευμένη πληροφορία στα MFI και με ελάχιστο υπολογιστικό κόστος, προτείνουμε τον αλγόριθμο MFI-drive που απαντάει σε ερωτήματα εύρεσης υπερσυνόλου και υποσυνόλου αντικειμένων, καθώς και συνόλων αντικειμένων με προκαθορισμένο βαθμό ομοιότητας σε σχέση με ένα δεδομένο σύνολο.
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While decision-making under uncertainty is a major universal problem, its implications in the field of transportation systems are especially enormous; where the benefits of right decisions are tremendous, the consequences of wrong ones are potentially disastrous. In the realm of highway systems, decisions related to the highway configuration (number of lanes, right of way, etc.) need to incorporate both the traffic demand and land price uncertainties. In the literature, these uncertainties have generally been modeled using the Geometric Brownian Motion (GBM) process, which has been used extensively in modeling many other real life phenomena. But few scholars, including those who used the GBM in highway configuration decisions, have offered any rigorous justification for the use of this model. This thesis attempts to offer a detailed analysis of various aspects of transportation systems in relation to decision-making. It reveals some general insights as well as a new concept that extends the notion of opportunity cost to situations where wrong decisions could be made. Claiming deficiency of the GBM model, it also introduces a new formulation that utilizes a large and flexible parametric family of jump models (i.e., Lévy processes). To validate this claim, data related to traffic demand and land prices were collected and analyzed to reveal that their distributions, heavy-tailed and asymmetric, do not match well with the GBM model. As a remedy, this research used the Merton, Kou, and negative inverse Gaussian Lévy processes as possible alternatives. Though the results show indifference in relation to final decisions among the models, mathematically, they improve the precision of uncertainty models and the decision-making process. This furthers the quest for optimality in highway projects and beyond.