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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
671

Integração de um modelo matemático de quantidade de água em rede de fluxo (ACQUANET) com um modelo matemático de qualidade de água em represas (CE-QUAL-R1) - Estudo de Caso: Represa Jaguari-Jacareí - Sistema Cantareira. / Integration of a water quantity mathematical net-flux model (ACQUANET) with a water quality mathematical reservoir model (CE-QUAL-R1) - Case Study: Jaguari-Jacarei Reservoir – Cantareira System.

Albano, Gustavo Doratioto 16 September 2004 (has links)
Desenvolveu-se uma metodologia para integração de dois modelos matemáticos, um de quantidade de água, em rede de fluxo, denominado ACQUANET com outro de qualidade de água, de uma dimensão, aplicado a represas, denominado CE-QUAL-R1. Para tanto, foi elaborada uma INTERFACE em linguagem de programação possibilitando que as vazões resultantes, simuladas pelo ACQUANET, servissem como dados de entrada ao CE-QUAL-R1 para simular a distribuição vertical das variáveis de qualidade de água em uma represa. Essa metodologia foi aplicada à Represa Jaguari-Jacareí no Sistema Cantareira em São Paulo, Brasil, como alternativa de gerenciamento quali-quantitativo, além de possibilitar o uso de retirada de água em diferentes profundidades, através da operação de tomadas d’água seletivas existentes. / A methodology was developed for the integration of two mathematical models, one of water quantity in network named ACQUANET with other of water quality, in one dimension, applied in revervoirs, named CE-QUAL-R1. In order to achieve this goal, an INTERFACE was developed to link the CE-QUAL-R1 with ACQUANET outflow results. It should be highlighted that ACQUANET has been used for beginning values of CE-QUAL-R1 and to simulate the vertical distribution of water quality variables in a reservoir. This methodology was applied to Jaguari-Jacarei Reservoir, of Cantareira System in Sao Paulo, Brazil, as a management quality and quantity tool of the system and it showed the use possibility of withdrawal of outflowing waters from different depths, through existing selective withdrawals ports operation.
672

Public housing tenant relocation: residential mobility, satisfaction, and the development of a tenant's spatial decision support system : thesis submitted for the degree of Doctor of Philosophy

Baker, Emma. January 2002 (has links) (PDF)
HomeLocater CD-ROM included as Appendix 8.3. Includes bibliographical references (leaves 233-250). An examination of residential mobility, and its outcomes focussing on the forced relocation of public housing tenants from The Parks area of metropolitan Adelaide. Investigates the process of public housing relocation and suggests means of improving relocation outcomes for individual tenants and their household. System requirements for accompanying CD-ROM: IBM compatible computer. Other requirements: InstallShield Wizard set-up program ; Winzip. Adobe Acrobat Reader is required to view or print the PDF files.
673

Public housing tenant relocation: residential mobility, satisfaction, and the development of a tenant's spatial decision support system thesis submitted for the degree of Doctor of Philosophy

Baker, Emma. January 2002 (has links)
Includes bibliographical references. Electronic publication; full text available in PDF format; abstract in HTML format. An examination of residential mobility, and its outcomes focussing on the forced relocation of public housing tenants from The Parks area of metropolitan Adelaide. Investigates the process of public housing relocation and suggests means of improving relocation outcomes for individual tenants and their household. Electronic reproduction.[Australia] :Australian Digital Theses Program,2001. x, 277 leaves : ill. (chiefly col.), maps ; 30 cm.
674

Coordinated management of urban wastewater systems by means of advanced environmental decision support systems

Murlà Tuyls, Damián 17 May 2013 (has links)
In the last decades and due to the Water Framework Directive implementation, the urban wastewater cycle management has become more complex. The concept of integrated urban wastewater system management is introduced, and it becomes necessary to consider some new data as the sewer system characteristics or the receiving body. In this sense, environmental decision support systems (EDSS) are very useful and powerful tools to support during the decision making process. A new EDSS for the integrated urban wastewater system management has been developed integrating data from several sources (bibliographic, theoretical or historical) and a real case-based virtual system able to perform simulations. Results demonstrate the benefits of using this kind of systems in comparison with a standard approach, which do not use the expert knowledge and encourages continuing with this research in order to improve the quality and efficiency of this type of EDSSs / En les darreres dècades, i degut a la implementació de la Directiva Marc de l’Aigua, la gestió del cicle urbà de l’aigua ha esdevingut més complexa. S’introdueix el concepte de gestió integrada de conca, i és necessari considerar certa informació, com les característiques de la xarxa de clavegueram o del medi receptor. D’aquesta manera, els sistemes de suport a la decisió ambiental (EDSS) són eines potentíssimes que faciliten la presa de decisions en aquest camp. S’ha desenvolupat un nou EDSS per a la gestió integrada de conca que utilitza una base sòlida de coneixement expert, integrant informació de diverses fonts (bibliogràfiques, teòriques o històriques) i dos sistemes virtuals basats en dades reals sobre els quals és possible realitzar simulacions. Els resultats demostren que aquest sistema presenta beneficis importants respecte a una gestió estàndard sense sistema expert, i esperona a prosseguir amb la recerca i el desenvolupament per a millorar-lo
675

Enhancing association rules algorithms for mining distributed databases : integration of fast BitTable and multi-agent association rules mining in distributed medical databases for decision support

Abdo, Walid Adly Atteya January 2012 (has links)
Over the past few years, mining data located in heterogeneous and geographically distributed sites have been designated as one of the key important issues. Loading distributed data into centralized location for mining interesting rules is not a good approach. This is because it violates common issues such as data privacy and it imposes network overheads. The situation becomes worse when the network has limited bandwidth which is the case in most of the real time systems. This has prompted the need for intelligent data analysis to discover the hidden information in these huge amounts of distributed databases. In this research, we present an incremental approach for building an efficient Multi-Agent based algorithm for mining real world databases in geographically distributed sites. First, we propose the Distributed Multi-Agent Association Rules algorithm (DMAAR) to minimize the all-to-all broadcasting between distributed sites. Analytical calculations show that DMAAR reduces the algorithm complexity and minimizes the message communication cost. The proposed Multi-Agent based algorithm complies with the Foundation for Intelligent Physical Agents (FIPA), which is considered as the global standards in communication between agents, thus, enabling the proposed algorithm agents to cooperate with other standard agents. Second, the BitTable Multi-Agent Association Rules algorithm (BMAAR) is proposed. BMAAR includes an efficient BitTable data structure which helps in compressing the database thus can easily fit into the memory of the local sites. It also includes two BitWise AND/OR operations for quick candidate itemsets generation and support counting. Moreover, the algorithm includes three transaction trimming techniques to reduce the size of the mined data. Third, we propose the Pruning Multi-Agent Association Rules algorithm (PMAAR) which includes three candidate itemsets pruning techniques for reducing the large number of generated candidate itemsets, consequently, reducing the total time for the mining process. The proposed PMAAR algorithm has been compared with existing Association Rules algorithms against different benchmark datasets and has proved to have better performance and execution time. Moreover, PMAAR has been implemented on real world distributed medical databases obtained from more than one hospital in Egypt to discover the hidden Association Rules in patients' records to demonstrate the merits and capabilities of the proposed model further. Medical data was anonymously obtained without the patients' personal details. The analysis helped to identify the existence or the absence of the disease based on minimum number of effective examinations and tests. Thus, the proposed algorithm can help in providing accurate medical decisions based on cost effective treatments, improving the medical service for the patients, reducing the real time response for the health system and improving the quality of clinical decision making.
676

A spatial decision support system for groundwater abstraction impact assessment and licensing

Basson, F. C. (Frederick Christoffel) January 2005 (has links)
Thesis (MSc)--Stellenbosch University, 2005. / ENGLISH ABSTRACT: Water resources in South Africa are limited and groundwater plays an important role in supporting basic human needs, sustaining ecosystems and enabling industrial and agricultural development. Sound management practices are necessary to ensure sustainable development of water resources. All groundwater usage must be licensed in compliance with the National Water Act of 1998. A Spatial Decision Support System (SDSS) can be used to assist in the groundwater usage licensing process of the Department of Water Affairs and Forestry (DWAF). The main aim of this study was to develop a SDSS, named Groundwater Abstraction & Licence Evaluation Tool (GALET), that could assist in the process of allocating water use licences and determining the local impact of abstraction, based on existing theory and data. The development was done within ArcView 3.2 using the scripting language Avenue. The Sandveld, an arid stretch of land along the west coast of South Africa that is heavily impacted by groundwater abstraction, was the chosen study area. The data collected for this study included existing borehole, recharge, rainfall and geological information. GALET proved to be capable of calculating essential information needed to evaluate groundwater abstraction, which included drawdown in the water table, zone of influence and the possible effects on features such as rivers and wetlands. Targeted potential users regarded GALET as a useful tool in the process of licensing and groundwater abstraction impact assessment and plans are under way to implement GALET or a derivative thereof at the DWAF regional offices. / AFRIKAANSE OPSOMMING: Waterhulpbronne in Suid-Afrika is beperk en grondwater speel 'n belangrike rol in die ondersteuning van basiese menslike behoeftes, volhouding van ekosisteme asook industriële en landbou-ontwikkeling. Betroubare bestuurspraktyke is noodsaaklik om die volhoubare ontwikkeling van waterhulpbronne te verseker. Alle grondwatergebruik moet volgens die Nasionale Waterwet van 1998 gelisensieer word. 'n Ruimtelike Besluitnemings Ondersteuning Stelsel (RBOS) kan as 'n hulpmiddel gebruik word in die lisensiëringsproses van die Departement van Waterwese en Bosbou. Die hoofdoel van hierdie studie was om 'n RBOS, genoem Groundwater Abstraction & Licence Evaluation Tool (GALET), te ontwikkel wat as hulpmiddel gebruik kan word in die allokeringsproses van watergebruiklisensies en die bepaling van die impak van grondwateronttrekking op die omgewing, gebaseer op bestaande teorie en data. Die ontwikkeling is in ArcView 3.2 met die programmeringstaal Avenue gedoen. Die Sandveld, 'n ariede streek aan die weskus van Suid-Afrika wat onderhewig is aan grootskaalse grondwateronttrekking, is gekies as die studie area. Die data wat vir hierdie studie ingesamel is sluit bestaande boorgat, grondwateraanvulling, reënval en geologiese inligting in. GALET was in staat om belangrike inligting aangaande die evaluering van grondwateronttrekking te bereken, o.a. die daling van die grondwatervlak, die impaksone en die moontlike effekte op landvorms soos riviere en vleilande. Die teikengroep potensiële gebruikers het GALET as 'n nuttige hulpmiddel in die proses van lisensiëring en grondwateronttrekking impakbepaling beskou en planne is onderweg om dit of 'n aangepaste program by die streekskantore van die Departement van Waterwese en Bosbou te implementeer.
677

An?lise dos indicadores de qualidade versus taxa de abandono utilizando m?todo de regress?o m?ltipla para servi?o de banda larga

Fernandes Neto, Andr? Pedro 20 June 2008 (has links)
Made available in DSpace on 2014-12-17T14:52:36Z (GMT). No. of bitstreams: 1 AndrePFN.pdf: 1525936 bytes, checksum: edb576494fd35f42e78d512df4fc02df (MD5) Previous issue date: 2008-06-20 / Telecommunication is one of the most dynamic and strategic areas in the world. Many technological innovations has modified the way information is exchanged. Information and knowledge are now shared in networks. Broadband Internet is the new way of sharing contents and information. This dissertation deals with performance indicators related to maintenance services of telecommunications networks and uses models of multivariate regression to estimate churn, which is the loss of customers to other companies. In a competitive environment, telecommunications companies have devised strategies to minimize the loss of customers. Loosing customers presents a higher cost than obtaining new ones. Corporations have plenty of data stored in a diversity of databases. Usually the data are not explored properly. This work uses the Knowledge Discovery in Databases (KDD) to establish rules and new models to explain how churn, as a dependent variable, are related to a diversity of service indicators, such as time to deploy the service (in hours), time to repair (in hours), and so on. Extraction of meaningful knowledge is, in many cases, a challenge. Models were tested and statistically analyzed. The work also shows results that allows the analysis and identification of which quality services indicators influence the churn. Actions are also proposed to solve, at least in part, this problem / A ?rea de telecomunica??es ? uma das mais estrat?gicas e din?micas do mundo atual. Esse fato se deve a in?meras inova??es tecnol?gicas que afetaram a forma como as informa??es trafegam. O conhecimento deixou de ser percebido como um ac?mulo linear, l?gico e cronol?gico de informa??es e passou a ser visto como uma constru??o em rede, consequentemente a massifica??o da Internet banda larga em alta velocidade teve grande influ?ncia sobre esse fen?meno. Essa disserta??o aborda um estudo sobre medi??o de desempenho e servi?os de manuten??o em telecomunica??es, com o uso de ferramentas de descoberta de conhecimento em base de dados (KDD). Objetiva-se transformar informa??es, armazenadas nas bases de dados de uma grande empresa de telecomunica??es do pa?s, em conhecimento ?til. A metodologia de pesquisa utilizada focou no uso de an?lise de regress?o m?ltipla como ferramenta para estimar a taxa de abandono de clientes em servi?os de Internet de banda larga, como vari?vel dependente, e indicadores de qualidade de servi?o como vari?veis independentes. Modelos foram testados e analisados estatisticamente. O trabalho apresenta resultados que permitem analisar e identificar quais os indicadores de qualidade que exercem maior influ?ncia na taxa de abandono dos clientes. S?o propostas sugest?es que possam ser aplicadas para melhoria de qualidade do servi?o percebido e consequentemente diminui??es das perdas com a taxa de abandono
678

Integration of information management systems to enhance business intelligence at the Department of Transport in South Africa

Chauke, Tshepo 02 1900 (has links)
Public sector decision makers are confronted by pressures to make faster and better decisions as a result of the competitive environment they operate in. However, there is a trend in the public sector, including the Department of Transport (DoT) in South Africa, to invest in management information systems (MIS) that are highly fragmented and not aiding effective and timely decision-making. As a result, the country witnessed several service delivery protests since 2008 which also affected the public transport sector, such as the widespread burning of Metrorail trains several times by angry commuters. In most instances, poor service delivery emanates from the fact that public servants do not have information at their fingertips to make decisions. This quantitative study utilised Control Objectives for Information and Related Technologies 5 (COBIT 5) as a theoretical framework to investigate the integration of MIS at the DoT with a view to enhancing business intelligence for effective decision-making. Data were collected through a questionnaire directed at middle managers and senior managers that were selected through stratification of business units at the DoT, as well as analysis of documents such as system specifications and strategic plans. The study established that the DoT has several systems such as Alfresco, BAS, GIS, Logis and Persal to name a few, which serve different purposes. However, in most instances, the systems are not integrated as the current infrastructure did not support integration needs and plans to accommodate changing requirements. This is compounded by the system policy implementation constraints, as well as ageing legacy systems that are obsolete. The only component where MIS was found to be integrated, was in the financial business units (Supply Chain Management, Finance and Budgeting). Core business units use off-the-shelf systems and, in some cases, custom-made applications that do not integrate with any other system and thus hinder decision-making. In conclusion, decisions are made based on thumb-sucking, as management does not have access to comprehensive information that is stored in fragmented unintegrated systems. The study recommends that governance structures should be set up to deal with a more holistic business, information and technology architecture for the DoT that enable integration of various systems for effective decision-making. Failure to transform this pattern would lead to service delivery protests persisting. A further study on a framework to integrate MIS in the public sector is recommended. / Information Science / M. Inf.
679

Leilões eletrônicos reversos multiatributo : uma abordagem de decisão multicritério como instrumento de agregação de valor aos processos de compras do setor público brasileiro

Menezes, Ronald do Amaral January 2003 (has links)
Made available in DSpace on 2009-11-18T19:01:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2003 / Auctions are secular institutions used in the commercial relationships among individuaIs and organizations. They provi de greater flexibility to the processes of determination of prices and allocation of goods, increasing the space for negotiations among buyers and sellers. In the Internet, they have been used, in a growing way, in B2B and G2B electronic commerce, mostly through the model of reverse auctions. However, its unidimensional aspect reduces the negotiations to the variable price, producing, many times, bad results. In the Brazilian case, the Federal Government launched Comprasnet, an Internet public emarketplace, through which public organizations acquire goods and services from registered suppliers. Considering alI the available bidding modalities, 'Electronic Pregão' stands out, as an unidimensional reverse auction, based on price, through which suppliers dispute for contracts of the public administration. In the present work, the author proposes a multicriteria decision-making approach, based on Multi-attribute Utility Theory, as an alternative for the adoption of multi-attribute reverse auctions, adding value to Brazilian Public Buying Organizations. / Leilões são instituições seculares utilizadas nas relações comerciais entre indivíduos e organizações. Provêem maior flexibilidade aos processos de determinação de preços e alocação de bens, aumentando o espaço para negociações entre compradores e vendedores. Na Internet, têm sido empregados, de maneira crescente, em atividades de comércio eletrônico B2B e G2B, em sua maioria, através da modalidade de leilão reverso. No entanto, seu aspecto unidimensional reduz as negociações à variável preço, produzindo, muitas vezes, resultados aquém do desejado. No caso brasileiro, o Governo Federal instituiu o Portal Comprasnet, através do qual, as organizações públicas adquirem bens e serviços de fornecedores cadastrados. Dentre as modalidades de licitação disponíveis, destaca-se o Pregão Eletrônico, um mecanismo de leilão eletrônico reverso baseado no atributo preço, através do qual, fornecedores submetem lances decrescentes, na disputa por contratos do setor público. No presente trabalho, o autor propõe uma abordagem de decisão multicritério, baseada na Teoria da Utilidade Multiatributo, como uma alternativa para a adoção de leilões reversos baseados em múltiplos atributos e, consequentemente, para uma maior agregação de valor pelas organizações compradoras do setor público brasileiro.
680

Mapas cognitivos fuzzy dinâmicos aplicados em vida artificial e robótica de enxame / Dynamic fuzzy cognitive maps applied to artificial life and swarm

Chrun, Ivan Rossato 17 October 2016 (has links)
ANP / Este trabalho propõe o uso de Mapas Cognitivos Fuzzy Dinâmicos (DFCM, do inglês Dynamic Fuzzy Cognitive Maps), uma evolução dos Mapas Cognitivos Fuzzy (FCM), para o desenvolvimento de sistemas autônomos para tomada de decisões. O FCM representa o conhecimento de forma simbólica, através de conceitos e relações causais dispostas em um grafo. Na sua versão clássica, os FCMs são usados no desenvolvimento de modelos estáticos, sendo inapropriados para o desenvolvimento de modelos temporais ou dinâmicos devido à ocorrência simultânea de todas as causalidades em uma estrutura fixa dos grafos, i.e., os conceitos e suas relações causais são invariantes no tempo. O DFCM utiliza o mesmo formalismo matemático do FCM através de grafos, acrescentando funcionalidades, como por exemplo, a capacidade de auto adaptação através de algoritmos de aprendizagem de máquina e a possibilidade de inclusão de novos tipos de conceitos e relações causais ao modelo FCM clássico. A partir dessas inclusões, é possível construir modelos DFCM para tomada de decisões dinâmicas, as quais são necessárias no desenvolvimento de ferramentas inteligentes em áreas de conhecimento correlatas à engenharia, de modo especifico a construção de modelos aplicados em Robótica Autônoma. Em especial, para as áreas de Robótica de Enxame e Vida artificial, como abordados nesta pesquisa. O sistema autônomo desenvolvido neste trabalho aborda problemas com diferentes objetivos (como desviar de obstáculos, coletar alvos ou alimentos, explorar o ambiente), hierarquizando as ações necessárias para atingi-los, através do uso de uma arquitetura para o planejamento, inspirada no modelo clássico de Subsunção de Brooks, e uma máquina de estados para o gerenciamento das ações. Conceitos de aprendizagem de máquina, em especial Aprendizagem por Reforço, são empregadas no DFCM para a adaptação dinâmica das relações de casualidade, possibilitando o controlador a lidar com eventos não modelados a priori. A validação do controlador DFCM proposto é realizada por meio de experimentos simulados através de aplicações nas áreas supracitadas. / This dissertation proposes the use of Dynamic Fuzzy Cognitive Maps (DFCM), an evolution of Fuzzy Cognitive Maps (FCM), for the development of autonomous system to decision-taking. The FCM represents knowledge in a symbolic way, through concepts and causal relationships disposed in a graph. In its standard form, the FCMs are limited to the development of static models, in other words, classical FCMs are inappropriate for development of temporal or dynamic models due to the simultaneous occurrence of all causalities in a permanent structure, i.e., the concepts and the causal relationships are time-invariant. The DFCM uses the same mathematical formalism of the FCM, adding features to its predecessor, such as self-adaptation by means of machine learning algorithms and the possibility of inclusion of new types of concepts and causal relationships into the classical FCM model. From these inclusions, it is possible to develop DFCM models for dynamic decision-making problems, which are needed to the development of intelligent tools in engineering and other correlated areas, specifically, the construction of autonomous systems applied in Autonomous Robotic. In particular, to the areas of Swarm Robotics and Artificial Life, as approached in this research. The developed autonomous system deals with multi-objective problems (such as deviate from obstacle, collect target or feed, explore the environment), hierarchizing the actions needed to reach them, through the use of an architecture for planning, inspired by the Brook’s classical Subsumption model, and a state machine for the management of the actions. Learning machine algorithms, in particular Reinforcement Learning, are implemented in the DFCM to dynamically tune the causalities, enabling the controller to handle not modelled event a priori. The proposed DFCM model is validated by means of simulated experiments applied in the aforementioned areas.

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