<p>Циљ истраживања реализованих у овом раду, био је да се формално опишу типови ограничења у XML моделу података, по угледу на типове ограничења у релационом моделу података. У складу са постављеним циљем, урађена је класификација типова ограничења у XML моделу података, њихова формална спецификација и имплементација у репрезентативним XML СУБП.</p> / <p>Cilj istraživanja realizovanih u ovom radu, bio je da se formalno opišu tipovi ograničenja u XML modelu podataka, po ugledu na tipove ograničenja u relacionom modelu podataka. U skladu sa postavljenim ciljem, urađena je klasifikacija tipova ograničenja u XML modelu podataka, njihova formalna specifikacija i implementacija u reprezentativnim XML SUBP.</p> / <p>The goal of the research conducted in this thesis was to formally describe the types of the constraints in the XML data model, according to the types of the constraints in the relational data model. In accordance with the set goal, the types of the constraints in the XML data model were classified, formally specified, and implemented in the representative XML DBMS.</p>

Doctor of Philosophy / Department of Biological & Agricultural Engineering / Kyle R. Douglas-Mankin / Water quality trading (WQT) is a market-based approach to improve water quality. It is an innovative, voluntary program that connects point source (PS) dischargers who need to reduce their pollutant loads with land managers who could offset those loads with nonpoint source (NPS) reductions to economically achieve water quality improvements in a watershed. The potential issues impeding WQT are its inability to address trading risks and quantify the uncertainty of potential load reduction in trades between PS and NPS. Recent research has also shown that trading information level and transaction costs cause problems in implementing WQT. Therefore, the goals of this study were to quantify the uncertainties of pollutant load reduction and delivery effect for potential trades, to estimate their spatiotemporal variations, and to provide information for stakeholders to reduce intangible costs of WQT. This study simulated agricultural cropland with more than 225 alternative land management practices to identify trends among these scenarios. Both total nitrogen and total phosphorus loads were modeled with SWAT and EUTROMOD for 36 years to analyze the potential load reduction, in-field uncertainty ratio, in-stream delivery ratio, and overall trading ratio (TR) in Lower Kansas watershed, Kansas. The analyses of site-specific effects in both geospatial and temporal aspects were also applied on subbasin level. The variant loading patterns and time distributions of each subbasin showed strong site-specific phenomena. The ANOVA of in-field nutrient load showed significant differences among the design criteria of scenarios. The results also showed a significant delivery and lake effects within the subbasins. The overall TR ranged from 1 to 2.2 or more in different scenarios. The advanced cluster analysis presented a potential method to eliminate the problems involved in fixed TRs while keeping the method simpler than finer-resolution floating TR system. Based on WQT geospatial data model, a three-tier GIS-based web interface Water Quality Trading Information Platform System (WQTIPS) was then developed for WQT information and assessment. A case study demonstrated WQTIPS can provide systematic, spatially information for stakeholders to assess the potential environmental benefit changes from the land management shifts using a simple interface. This study demonstrated that it is possible to automate water-quality trades, use watershed models to minimize trading risk and maximize water-quality benefits, and prioritize among possible trades both spatially and by BMP.

This paper uses data for 255 NUTS-2 European regions over the period 1995-2003 to test the relative explanatory performance of two important rival theories seeking to explain variations in the level of economic development across regions, namely the neoclassical model originating from the work of Solow (1956) and the so-called Wage Equation, which is one of a set of simultaneous equations consistent with the short-run equilibrium of new economic geography (NEG) theory, as described by Fujita, Krugman and Venables (1999). The rivals are non-nested, so that testing is accomplished both by fitting the reduced form models individually and by simply combining the two rivals to create a composite model in an attempt to identify the dominant theory. We use different estimators for the resulting panel data model to account variously for interregional heterogeneity, endogeneity, and temporal and spatial dependence, including maximum likelihood with and without fixed effects, two stage least squares and feasible generalised spatial two stage least squares plus GMM; also most of these models embody a spatial autoregressive error process. These show that the estimated NEG model parameters correspond to theoretical expectation, whereas the parameter estimates derived from the neoclassical model reduced form are sometimes insignificant or take on counterintuitive signs. This casts doubt on the appropriateness of neoclassical theory as a basis for explaining cross-regional variation in economic development in Europe, whereas NEG theory seems to hold in the face of competition from its rival. (authors' abstract)

As informações contidas em uma Base de Dados para projeto não são obtidas apenas cumulativamente, mas também através de refinamentos e mudanças sucessivas nas informações já disponíveis. Diversas pesquisas mostram-se preocupadas com este aspecto e propõem conceitos e mecanismos de controle de Versões que podem ser incorporados a Modelos de Bases de Dados Orientadas a Objetos. Alguns destes trabalhos, aqui estudados, focalizam o uso de Versões na evolução não apenas da Base de Dados Extensional (Instâncias), ou seja, nas informações colhidas do mundo real e utilizadas pelas aplicações, mas também sua utilização como um mecanismo eficiente de Evolução do Esquema de Dados (a Base de Dados Intencional). Com o objetivo principal de constituir um núcleo básico de conceitos e mecanismos que possam atender as mais variadas aplicações, este trabalho estabelece um Modelo de Versões apoiado no conceito de Objeto Composto e que permite uma correlação direta e transparente entre Versões de Instâncias e de Esquemas, ou seja, cada Versão na Base Extensional tem relação direta e única com a Versão da Base Intencional utilizada em sua instanciação. Adicionalmente, este trabalho estabelece um Meta-Modelo de Versões cujas especificações poderão direcionar as pesquisas de futuros Modelos de Versões, no sentido de apoiar a elaboração de Modelos de Versões sofisticados ou simples para aplicações específicas ou gerais, e também poderão ser utilizadas para o estabelecimento de mecanismos para a classificação e comparação de Modelos de Versões. / Data stored in project databases are obtained not only by the increasing inclusion of more and more data, but also through refinements and alterations into the already existent information. There are many works involving those subjects, studying concepts and control mechanisms to support data versioning in Object-Oriented Database Systems. Some of these works focus on the Version Control support in the stored data (the Extensional Database), aiming at recognizing and controlling the occurrence of many data versions from the same subject. Other works focus on the support of version control over the Data Schema (the Intentional Database), aiming at finding mechanisms that permit the recovery of different data structured in different ways from the same subject. This work presents a Version Model, based on the Composite Objects concept, providing a homogeneous support to Version Control in the Extensional and the Intentional Databases. In this model, the Extensional data is partitioned into Composite Objects, and the parts of each Object are interpreted with only one of several possible schemes that are used to instantiate the parts of objects of this kind. This Version Model was conceived to be useful to a broad range of application domains, deriving a set of concepts that had permitted to construct a Version Meta-Model. The Meta-Model is sufficiently generic to aid constructing elementary or complex Version Models, applied to generic or specific needs, and depicting mechanisms to aid the classification and comparison of existing or proposed Version Model.

Os Sistemas de Armazenamento e Comunicação de Imagens Médicas fornecem, para os físicos, médicos e técnicos de um centro de saúde, informações gráficas sobre vários aspectos envolvidos no diagnóstico de cada paciente. Atualmente, os exames médicos produzem uma grande quantidade de informação em função dos equipamentos médicos computadorizados, utilizados principalmente para se obter dados imagens internas dos pacientes. Este trabalho descreve os conceitos utilizados em Sistema de Banco de Dados Orientado a Objetos para manipular imagens medicas, de tal forma que possam ser recuperadas através de consultas, baseadas na descrição de seu conteúdo gráfico. A abordagem tradicional utiliza ícones e atributos textuais, armazenados juntamente com as imagens, para especificar as consultas. Este trabalho utiliza uma nova técnica de modelagem para definir o \"tipo de dado imagem\", que permite decidir, anteriormente à execução da consulta, os dados que possam ser significativos para cada imagem, no instante que esta é armazenada no Banco de Dados. Desta forma, a busca por uma determinada informação pode ser acelerada. durante a avaliação de uma consulta. / Picture Archiving and Communication System (PACS) applied in medical image storage provides graphical information of many aspects of the health, diseases and treatment of each patient for the physician and technicians of a health care center. Nowadays, medical exams can generate a large amount of data due to the computerized medical instruments used to collect the graphical information about the patients. This work describes the concepts used in an Object Oriented Data Base System to deal with medical images, so that it can be retrieved through queries based on the graphic contents of the stored images. The usual approach uses icons and textual attributes stored with the images to specify the queries. This work uses a novel modeling technique to define the \"image data type\", through which it is possible to decide, beforehand the query itself, the valuable data of each image when it is stored in the database, so the search can be accelerated when queries are issued.

Submitted by Nara Lays Domingues Viana Oliveira (naradv) on 2015-07-07T15:00:58Z No. of bitstreams: 1 katiane.pdf: 351762 bytes, checksum: 315dcef5eaf98ff120848c68ab48e8aa (MD5) / Made available in DSpace on 2015-07-07T15:00:58Z (GMT). No. of bitstreams: 1 katiane.pdf: 351762 bytes, checksum: 315dcef5eaf98ff120848c68ab48e8aa (MD5) Previous issue date: 2014 / Nenhuma / Este estudo tem como objetivo apontar os determinantes mais relevantes na definição do preço médio do milho exportado no mercado mundial, no intuito de prover informações aos agentes econômicos. Trata do panorama atual do mercado mundial de milho, partindo-se de 2000, quando houve o boom dos preços das commodities. Nesse sentido, o modelo econométrico proposto para o presente estudo consiste no modelo estatístico estruturado com base em dados em painel, com periodicidade anual entre o período de 2000 a 2012. Para uma melhor compreensão das análises, primeiramente apresentou-se, nos primeiros capítulos, uma revisão dos conceitos teóricos e empíricos que abordam os principais fatores determinantes na definição do preço médio do milho exportado. Posteriormente, analisou-se se o exercício desenvolvido trata-se realmente de um modelo de dados em painel, realizando o teste F para significância em conjunto das dummies de país. Também foi definido através do teste de Hausman que o estimador de efeito fixo é o indicado. Assim, foram elaborados quatro modelos, sendo que o modelo D instrumentalizando a variável exportação de milho em kg pela variável exportação de milho em kg defasada em 1 período apresentou os resultados mais consistentes e conclusivos em relação ao embasamento teórico dos capítulos iniciais. Dentre os principais resultados, fica evidenciada que o principal determinante da alteração do preço de exportação do milho é a variável taxa de câmbio real efetiva. Também mostraram-se significativas as variáveis exportações (em kg) de milho do país para o mundo; exportações de carne suína dos principais destinos das exportações de milho do país; e população urbana dos principais destinos das exportações de milho do país. / The objective of this study is to indicate the most important determinants in the worldwide exported maize average price in order to provide information to economic agents. Treats the world maize market current situation, starting at 2000 when there was a boom in commodity prices. This way, the econometric model proposed for this study is structured in the statistical model based on panel data on an annual basis between the period 2000 up to 2012. For the analysis better understanding, a review of theoretical and empirical concepts was previously presented in the early chapters, which deals the main factors in defining the exported maize average price. After, the developed exercise was analyzed performing the F test for significance in all the country dummies, in order to prove that this is really a panel data model. Was also defined by the Hausman test that is indicated the fixed effect estimator to this model. Thus, four models were made, and the D model, instrumenting the variable maize export (in kg) with the variable maize export (in kg) lagged 1 period, and it presented most consistent and conclusive results regarding the theoretical basis of the initial chapters. Among the main results, it is evident that the main determinant of the maize export price variation is the real effective exchange rate variable. Also revealed that the variables country maize exports (in kg) to the world; pork meat exports of the main maize export destinations; and urban population of the main maize export destinations are significant.

Due to the successful application in internet related fields, Extensible Markup Language (XML) and its related technologies are being explored as a revolutionary software file format technology used to provide increased interoperability in the discrete-event simulation (DES) arena. The National Institute of Standards and Technology (NIST) has developed an XML-based information model (XSD) called the Shop Data Model (SDM), which is used to describe the contents of a neutral file format (NFF) that is being promoted as a means to make manufacturing simulation technology more accessible to a larger group of potential customers. Using a two step process, this thesis evaluates the NIST SDM information model in terms of its ability to encapsulate the informational requirements of one vendor's simulation model information conceptually and syntactically in order to determine its ability to serve as an NFF for the DES industry. ProModel Corporation, a leading software vendor in the DES industry since 1988, serves as the test case for this evaluation. The first step in this evaluation is to map the contents of ProModel's information model over to an XML schema file (XSD). Next, the contents of this new XSD file are categorized and compared to the SDM information model in order to evaluate compatibility. After performing this comparison, observations are made in relation to the challenges that simulation vendors might encounter when implementing the proposed NIST SDM. Two groups of limitations are encountered which cause the NIST SDM to support less than a third of the ProModel XSD elements. These two groups of limitations are: paradigm differences between the two information models and limitations posed due to the incomplete status of the NIST SDM specification. Despite these limitations, this thesis shows by comparison that XML technology does not pose any limitation which would invalidate its ability to syntactically represent a common information model or associated XML NFF. While only 28% of the ProModel element are currently supported by the SDM, appropriate changes to the SDM would allow the information model to serve as a foundation upon which a common information model and neutral file format for the DES industry could be built using XML technologies.

Much research has been undertaken to gain insight into business alignment of IT. This alignment basically aims to improve a firm’s performance by an improved harmonization of the business function and the IT function within a firm. The thesis discusses previous approaches and constructs an overall framework, which a potential approach needs to fit in. Being in a highly regulated industry, for airports there is little space left to increase revenues. However, the retailing business has proven to be an area that may contribute towards higher income for airport operators. Consequently, airport management should focus on supporting this business segment. Nevertheless, it needs to be taken into account that smooth airport operations are a precondition for successful retailing business at an airport. Applying the concept of information intensity, the processes of gate allocation and airport retailing have been determined to appraise the potential that may be realized upon (improved) synchronization of the two. It has been found that the lever is largest in the planning phase (i.e. prior to operations), and thus support by means of information technology (for information distribution and improved planning) may help to enable an improved overall retail performance. In order to determine potential variables, which might influence the output, a process decomposition has been conducted along with the development of an appropriate information model. The derived research model has been tested in different scenarios. For this purpose an adequate gate allocation algorithm has been developed and implemented in a purposewritten piece of software. To calibrate the model, actual data (several hundred thousand data items from Frankfurt Airport) from two flight plan seasons has been used. Key findings: The results show that under the conditions described it seems feasible to increase retail sales in the magnitude of 9% to 21%. The most influential factors (besides the constraining rule set and a retail area’s specific performance) proved to be a flight’s minimum and maximum time at a gate as well as its buffer time at gate. However, as some of the preconditions may not be accepted by airport management or national regulators, the results may be taken as an indication for cost incurred, in case the suggested approach is not considered. The transferability to other airport business models and limitations of the research approach are discussed at the end along with suggestions for future areas of research.

No description available.

The health and well-being of individuals is related to their activity-travel patterns. Individuals who undertake physically active episodes such as walking and bicycling are likely to have improved health outcomes compared to individuals with sedentary auto-centric lifestyles. Activity-based travel demand models are able to predict activity-travel patterns of individuals at a high degree of fidelity, thus providing rich information for transportation and public health professionals to infer health outcomes that may be experienced by individuals in various geographic and demographic market segments. However, models of activity-travel demand do not account for the attitudinal factors and lifestyle preferences that affect activity-travel and mode use patterns. Such attitude and preference variables are virtually never collected explicitly in travel surveys, rendering it difficult to include them in model specifications. This paper applies Bhat’s (2014) Generalized Heterogeneous Data Model (GHDM) approach, whereby latent constructs representing the degree to which individuals are health conscious and inclined to pursue physical activities may be modeled as a function of observed socio-economic and demographic variables and then included as explanatory factors in models of activity-travel outcomes and walk and bicycle use. The model system is estimated on the 2005-2006 National Health and Nutrition Examination Survey (NHANES) sample, demonstrating the efficacy of the approach and the importance of including such latent constructs in model specifications that purport to forecast activity and time use patterns. / text