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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.
1

Asset Levels of Service-based Decision Support System for Municipal Infrastructure Investment

Sharma, Vishal 06 1900 (has links)
The single biggest challenge facing municipalities today is a shortage of funds and labor for upgrading and expanding aging infrastructure. This continued lack of funding impairs the municipalities ability to maintain desired levels of service. Over the last decade, many Canadian municipalities have faced pressures of increasing complexity in infrastructure asset management decision-making which can be partly attributed to cost escalation, increasing service demand and interdependencies between networks. The goal of this research is to develop the framework for Asset Levels of Service (ALOS)-based decision support systems for municipal infrastructure network investment. The proposed framework is based on the fact that ALOS should be one of the main criteria for municipal infrastructure maintenance, repair and rehabilitation (MR&R). Since ALOS is based on qualitative and quantitative parameters, the use of ALOS in municipal infrastructure MR&R decisions will result in improved funding allocation. Secondary parameters used for municipal infrastructure investment decision making in the proposed framework are the physical deterioration of assets, future growth and the impact on the dependent infrastructure network. The proposed framework focuses on funding allocation for the MR&R of municipal networks. The framework is applicable to municipal infrastructure networks, excluding the other assets such as buildings, parks, etc. Application of the proposed framework is demonstrated by its implementation in the case of urban roads. Implementation is carried out in four phases. Phase I involves the quantification of ALOS for urban roads. Quantification of ALOS for urban roads has various challenges such as multiple users and interdependencies of levels of services between various users. An Analytical Hierarchy Process (AHP) has been used to quantify ALOS. Phase II involves the determination of a multiattribute utility function for investment decision. Calculated multiattribute utility of investment decision is used in the multiobjective optimization model in Phase III. In Phase IV, the proposed methodology is incorporated into a computer application called OPTIsys (OPTImum Infrastructure SYStems). OPTIsys will facilitate MR&R decision making based on fully integrated considerations of ALOS, future demand and network interdependencies. Stakeholders benefiting from OPTIsys include the general public, asset-managers, infrastructure departments and municipal councils. OPTIsys will enable infrastructure departments to maintain the operational capability of the network in compliance with the targeted levels of service. Overall, municipalities will be able to reduce the infrastructure deficit while maximizing economic returns. / Construction Engineering and Management
2

Asset Levels of Service-based Decision Support System for Municipal Infrastructure Investment

Sharma, Vishal Unknown Date
No description available.
3

Χρήση της περιβάλλουσας ανάλυσης δεδομένων για την αποδοτική κάλυψη ή σύμπτηξη ενός συνόλου

Γεωργαντζίνος, Στυλιανός 11 January 2010 (has links)
Στην παρούσα μεταπτυχιακή εργασία περιγράφεται η διαδικασία συνδυασμού προβλημάτων Επιχειρησιακής Έρευνας με την μεθοδολογία εύρεσης συγκριτικής αποδοτικότητας (DEA). Αρχικά, παρουσιάζεται μια γενική περιγραφή της μεθόδου DEA και μια συνοπτική επισκόπηση της σχετικής βιβλιογραφίας. Παρουσιάζεται ο τρόπος συνδυασμού της μεθόδου DEA και δύο κλασσικών μοντέλων χωροθέτησης εγκαταστάσεων, του μοντέλου με περιορισμό και του αντίστοιχου μοντέλου χωρίς περιορισμό στην χωρητικότητα. Για την επίτευξη αυτού του στόχου γίνονται οι απαραίτητοι χειρισμοί στην μέθοδο DEA ούτως ώστε να μπορεί να υπολογίζεται η αποδοτικότητα για όλες τις μονάδες λήψης απόφασης ταυτόχρονα – μέθοδος ταυτόχρονης DEA (Simultaneous DEA), εφόσον το κλασσικό μοντέλο βρίσκει την αποδοτικότητα μιας μονάδας λύνοντας μια φορά το γραμμικό πρόβλημα με τους συντελεστές βαρύτητας αυτής της μονάδας. Η λύση του πολυκριτήριου προβλήματος αναδεικνύει την αλληλεπίδραση μεταξύ κόστους και αποδοτικότητας, για τη λήψη απόφασης ανάλογα με τις ανάγκες που μπορεί ενυπάρχουν σε ένα αντίστοιχο πραγματικό πρόβλημα. Στην συνέχεια αναπτύσσεται για πρώτη φορά στη διεθνή βιβλιογραφία μια μεθοδολογία για το συνδυασμό δύο άλλων βασικών προβλημάτων, της κάλυψης και της σύμπτυξης συνόλου, αντίστοιχα, με την μεθοδολογία DEA. Στόχος είναι να μορφοποιηθεί ένα μοντέλο γραμμικού προγραμματισμού έτσι ώστε εκτός από το μέτρο απόφασης του κόστους για την κάλυψη ή σύμπτυξη ενός συνόλου-στόχου, από διαθέσιμα υποσύνολα να ληφθεί υπόψη και η αποδοτικότητα του εκάστοτε υποσυνόλου, η οποία εν τέλει θα επηρεάσει και την συνολική αποδοτικότητα του συνόλου-στόχου. Γίνεται ο συνδυασμός των μεθοδολογιών και αναπτύσσονται μεθοδολογίες πολυκριτήριας ανάλυσης που μπορούν να χρησιμοποιηθούν για την λήψη αποφάσεων που αφορούν την αποδοτική και οικονομική κάλυψη ή σύμπτυξη ενός συνόλου. Για την πιστοποίηση και τη διαπίστωση της λειτουργικότητας των προτεινόμενων μεθοδολογιών αναπτύσσονται παραδείγματα προβλημάτων, τα οποία και επιλύονται επιτυχώς. / In the present thesis, the combination of Operation Research Problems with the Data Envelopment Analysis (DEA) is performed in order to make optimal and efficient decisions. Firstly, a general description of DEA and a breath literature review is presented. Then, we show and test location modeling formulations that utilize data envelopment analysis (DEA) efficiency measures to find optimal and efficient facility location/allocation patterns. In addition, to the authors’ best knowledge, the combinations of DEA with the Set Covering Problem as well as Set Packing Problem are formulated as multiobjective problems, for first time in the literature. The main aim of the proposed models is to make cost-effective and efficient decisions regarding the Set Covering and Packing Problem, respectively. Numerical examples are developed in order to validate and test the novel models. The numerical results of multiobjective analysis demonstrate that the proposed methods are able to successfully find optimal and efficient solutions for real set covering, packing and partitioning problems.
4

Análises multiobjetivo, baseada em programação linear, e comparativas para agriculturas de manejo convencional e orgânico. / Multiobjective analysis, based on linear programming, and comparatives for conventional and organic management.

ALENCAR, Vladimir Costa de. 10 September 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-09-10T18:01:33Z No. of bitstreams: 1 VLADIMIR COSTA DE ALENCAR - TESE PPGRN 2009..pdf: 9290550 bytes, checksum: cdd4f50a45bc398ddd2ac6cdfd4cdb0d (MD5) / Made available in DSpace on 2018-09-10T18:01:33Z (GMT). No. of bitstreams: 1 VLADIMIR COSTA DE ALENCAR - TESE PPGRN 2009..pdf: 9290550 bytes, checksum: cdd4f50a45bc398ddd2ac6cdfd4cdb0d (MD5) Previous issue date: 2009-11 / À nível mundial, está ocorrendo gradativamente a mudança da matriz alimentar da humanidade. Em função de um maior nível de informação da sociedade, a partir dos meios de comunicação de massa e pesquisas acadêmicas, está aumentando o consumo de carnes brancas, frutas, verduras e legumes. Além disso, há um componente político-ideológico, onde os consumidores passam a preferir alimentos que não sejam produzidos com a exploração de mão-de-obra infantil, sem agressão do meio ambiente e com tecnologias de produção de baixo custo, sem o uso de agroquímicos (agrotóxicos e adubos químicos). A preservação dos recursos naturais não renováveis passa a ser a pauta do dia, e a sustentabilidade emerge com uma grande importância. Diante desse quadro, a agricultura orgânica tem se fortalecido, vindo da necessidade de alimentos limpos (sem resíduos tóxicos) que a sociedade moderna exige e por conseqüência a preservação da natureza. Este trabalho teve como finalidade uma análise comparativa multiobjetivo de um sistema de produção convencional e um sistema de produção orgânico, tendo como base as áreas irrigadas da cidade de Boqueirão, Estado da Paraíba, onde possui um reservatório que abastece várias cidades deste estado. Foi utilizada uma série de 10 anos hidroclimáticos da região. Para execução deste trabalho foi utilizado (e adicionadas funcionalidades) um sistema de apoio à decisão que utiliza programação linear para otimização multiobjetivo de análises de seleção de culturas para áreas irrigadas. Foram demonstrados, através de cenários, que o manejo orgânico tem um ganho maior em relação ao manejo convencional em relação à receita líquida, mão-de-obra, saúde humana e preservação ambiental. / In worldwide level, a change of humanity’s food matrix is gradually occurring. Because of a higher level of information that society’s receiving, through mass media and academic researches, the consumption of white meat, fruits and vegetables is rising. Also, there is a political-ideological component, in which consumers tend to prefer food that is not produced through infantile labour exploitation, that doesn’t harm the environment while it’s being produced and that, when produced, uses technology of production with low cost, without the usage of agrochemicals (pesticides and chemical fertilizers). The preservation of not renewable natural resources is at the top of the agenda, and sustainability emerges with a great importance. Before this frame, organic agriculture has strengthened, because of modern society’s demand for clean food (without toxic residues), and consequently for nature protection. The present work had the objective of developing a multiobjective comparative analysis of a production system that utilizes conventional management (using agrochemicals – fertilization and pesticides) and of a production system that uses organic management, on Epitácio Pessoa Reservoir (Boqueirão), in the State of Paraíba, through a 10 climatic years scenario. In this work a DSS (Decision Support System) was used with the purpose of applying a multiobjective optimization based on linear programming to crop selection analysis in irrigated areas. It has been shown that agricultural organic management provides better net profit, use of human labor and health and environmental protection than conventional management.

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