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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.
51

A Novel Dataset for the Transport Sector in a Province of Peru

Guerrero, Miguel Arango, Juárez, Pedro Shiguihara 01 January 2021 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Problems related to public transport and private transport in Peru are persistent. New proposals to solve them arise, currently the world of data analysis is starting in Peru, there are not many open datasets useful that allow proposing solutions in each environment. In this paper, we will collect relevant data of the transport located in a province of Peru with more than 1000 users involved, restricted by a delimited geographic area and with 2 years of operations and more than 3000 transport services tracked. In this way, we highlight the importance of the data, the possible potential uses within the transport, and a case of use of the collected dataset. / Revisión por pares
52

Brno Komárov Město ve městě, prostorová a symbolická kostra Komárova / Brno-Komárov City In The City, space and symbolic structure of Komárov

Vochta, Miroslav January 2019 (has links)
Komárov is partially isolated city part with fragmented formally colourful structure and also a picture and character with high percentage of empty or degraded areas. Continuity on logistic knot, good transportation connection, planned and implemented squeeze out of major road and with that connected easing of current street net require new city planning of the whole area and therefore allows subsequent transformation of the area by way of overwritingand individualized intervention. This final thesis will be focused on examples of solving the substance of the city, by method of approaches and on stressing out the skeleton of public space with allocation of objects with symbolic structure. Content of this thesis City planning study of the area Komárov centre, stressing out of the symbolic skeleton and structure and the skeleton of public space with addition of related objects Architecture proposal of objects complementary to a structure and picture of area Program of new interventions and conversions of existing and preserved objects
53

Road Network Analysis based on Route Set Generation

Nåfält, Gustav, Tunholm, Mattias January 2020 (has links)
This thesis proposes an analysing tool that makes use of route set generation to perform road network analysis that can be used in both transport planning and traffic management analysis. The input to the tool is a routable road network and a geographical zoning system and the route set generation is performed on all Origin-Destination (OD) -pairs of the zoning system. The tool was implemented using a simplification of Stockholms road network and a zoning system defined by the Swedish Transport Administration. The result shows that a route set generation-based tool can provide support in both transport planning and traffic management, and that the procedure provides results within a reasonable amount of time. The tool provides both a general analysis of the road network, and a link capacity reduction analysis. In the latter, the proportion of affected destinations and mean travel time deterioration for each OD-zone work as metrics of how the zones are affected by the capacity reduction. Transport planners can use the tool to present the betweenness centrality, the proportion of affected destinations and the mean travel time deterioration, all of which are metrics that can be used to evaluate the potential need for new infrastructure. Traffic managers can use the proportion of affected destinations and the mean travel time deterioration as metrics that can be used to identify zones that are affected by a road capacity reduction. The betweenness centrality of the best alternative route can be used to support traffic diversion for a specific zone.
54

Actionable Traffic Signal Performance Measures from Large-scale Vehicle Trajectory Analysis

Enrique Daniel Saldivar Carranza (10223855) 19 July 2023 (has links)
<p>Road networks are significantly affected by traffic signal operations, which contribute from 5% to 10% of all traffic delay in the United States. It is therefore important for agencies to systematically monitor signal performance to identify locations where operations do not function as desired and where mobility could be improved.</p> <p><br></p> <p>Currently, most signal performance evaluations are derived from infrastructure-based Automated Traffic Signal Performance Measures (ATSPMs). These performance measures rely on high-resolution detector and phase information that is collected at 10 Hz and reported via TCP/IP connections. Even though ATSPMs have proven to be a valid approach to estimate signal performance, significant initial capital investment required for infrastructure deployment can represent an obstacle for agencies attempting to scale these techniques. Further, fixed vehicle detection zones can create challenges in the accuracy and extent of the calculated performance measures.</p> <p><br></p> <p>High-resolution connected vehicle (CV) trajectory data has recently become commercially available. With over 500 billion vehicle position records generated each month in the United States, this data set provides unique opportunities to derive accurate signal performance measures without the need for infrastructure upgrades. This dissertation provides a comprehensive suite of CV-based techniques to generate actionable and scalable traffic signal performance measures.</p> <p><br></p> <p>Turning movements of vehicles at intersections are automatically identified from attributes included in the commercial CV data set to facilitate movement-level analyses. Then, a trajectory-based visualization from which relevant performance measures can be extracted is presented. Subsequently, methodologies to identify signal retiming opportunities are discussed. An approach to evaluate closely-coupled intersections, which is particularly challenging with detector-based techniques, is then presented. Finally, a data-driven methodology to enhance the scalability of trajectory-based traffic signal performance estimations by automatically mapping relevant intersection geometry components is provided.</p> <p><br></p> <p>The trajectory data processing procedures provided in this dissertation can aid agencies make data-driven decisions on resource allocation and signal system modifications. The presented techniques are transferable to any location where CV data is available, and the scope of analysis can be easily varied from the movement to intersection, corridor, region, and state level.</p>
55

Transport poverty - integrerad analys av transportrelaterade sociala konsekvenser i Malmö

Varga, Tobias, Kvarnström, Magnus January 2016 (has links)
Uppsatsen tar sin utgångspunkt i dagens hållbara stadsutveckling och fokuserar på transportplaneringens roll i denna. Uppsatsen tar också sin utgångspunkt i hur transportforskare under senare år betonat problematiken med att människor med olika socioekonomiska förutsättningar har olika förutsättningar till mobilitet. För att motverka dessa processer har forskare under senare år utvecklat en rad koncept, verktyg och arbetsmetoder. Fokus för uppsatsen ligger på en undersökning av konceptet transport poverty och dess förekomst i Malmö. För att verkställa uppsatsens syfte - att undersöka konceptet transport poverty och dess förekomst i utvalda delar av Malmö, genomförs en litteraturstudie och en fallstudie i tre delar av Malmö. Uppsatsförfattarna redogör i litteraturstudien för hur transport poverty är ett koncept som belyser och förklarar relationer och samband mellan bristande transportmöjligheter och sociala problem. Uppsatsförfattarna redogör i litteraturstudien för hur transport poverty är ett koncept som består av fyra delar som behandlar aspekter som människors socioekonomiska förutsättningar, mobilitet, tillgänglighet, och utsatthet för trafikens externa effekter. I fallstudien används sedan litteraturstudiens resultat kring hur transport poverty kan identifieras och mätas och användas i en mätning av transport poverty i Malmö. Fallstudien utgår ifrån Malmö stads nyligen antagna Trafik- och mobilitetsplan och dess uppdelning av Malmö i femton så kallade TROMP-områden. I fallstudien används sekundärdata i form av befolkningsstatistik, resvaneundersökningar och tillgänglighetsindex som sedan integreras i en analys och visar på förekomsten av transport poverty i områdena Rosengård/Sorgenfri, Fosie och Limhamn. Slutsatser att dra från fallstudiens resultat är att förekomsten av transport poverty i de studerade områdena skiljer sig åt. Förekomsten av transport poverty är utifrån den integrerade analysen mycket större i områdena Fosie och Rosengård/Sorgenfri än i Limhamn. Analysen visar att de områden med sämst förutsättningar att med överkomliga medel betala för transport också är de områden där förekomsten av transport poverty är som störst. Analysen pekar på hur områdenas olika socioekonomiska förutsättningar tycks kunna förklara mycket av fallstudiens resultat. I ljuset av den tidigare forskningen kan dessa resultat ytterligare problematiseras och nyansera bilden av de transportrelaterade sociala konsekvensernas uppkomst och bakomliggande orsaker. Med hjälp av teorier kring social exclusion kan förekomsten av transport poverty i de studerade områdena betraktas vara beroende på människors individuella förutsättningar, men också av hur lokala, nationella och globala faktorer, såväl inom som utanför transportområdet, skapar, och återskapar transport poverty i Malmö. / This master thesis focuses on the role of transport planning in todays sustainable urban development. It starts off by highlighting the problems of unequal mobilities and how research on transport planning during later years has developed concepts, tools and methods to counteract such processes. The thesis main purpose is to examine the concept transport poverty and its presence in different geographical areas of Malmö. The purpose is executed through a literature review over the concept and a case study over its presence in three different areas. Conclusions from the literature review is that transport poverty is a concept that highlights and explains the inter-relationships between transport disadvantage and social policy issues. The literature review also makes clear that transport poverty is a broad, overarching notion, which encompasses the sub-concepts (lack of) transport affordability, mobility poverty, accessibility poverty and exposure to transport externalities. The results from the literature review are then used to develop indicators and methods to be used in the case study´s measure of transport poverty in Malmö. The case study starts off from the city of Malmös newly adopted transport plan and its division of Malmö into fifteen so-called TROMP-areas. The authors base their study on secondary data covering demographics, travel surveys and accessibility indexes in the areas Rosengård/Sorgenfri, Fosie and Limhamn. The case study leads to a number of conclusions. The presence of transport poverty in the areas that is studied differs, and is considerably greater in the areas Fosie and Rosengård/Sorgenfri than in Limhamn. The integrated analysis also shows that the areas with the greatest presence of transport poverty are also the areas suffering mostly from a lack of transport affordability. These findings could be explained by the areas different socioeconomic conditions. In light of previous research and its thesis of the appearance and underlying causes of the transport-related impacts, the results from the case study could be further problematized. Using theories of social exclusion, the presence of transport poverty in different parts of Malmö could be considered to be dependent on peoples individual circumstances, but also of how local, national and global factors, within and outside the transport sector, creates and recreates transport poverty in Malmö.
56

Strategisk miljöbedömning inom regional transportplanering : En fallstudie i Region Västernorrland / Strategic environmental assessment in regional transport planning

Iisakka, Anna, Lidén, Linnea January 2021 (has links)
För att nå en hållbar utveckling måste förhållandet mellan människor och miljö beaktas genom att ta hänsyn till ekologiska, sociala och ekonomiska aspekter. Proportionerna mellan dessa aspekter är inte lika då det visat sig att ekologisk hållbarhet är en förutsättning för social och ekonomisk hållbarhet. För att begränsa klimatpåverkan måste utsläpp av växthusgaser minska, och det innebär att det måste ske en omställning inom bland annat transportsektorn. Regeringen anger att utsläppen av växthusgaser inom transportsektorn måste minska kraftigt och i en snabbare takt för att i princip vara noll år 2045.  Under våren 2021 påbörjade Region Västernorrland processen med att revidera den gällande infrastrukturplanen som gäller mellan åren 2018–2029. Planen revideras vart fjärde år och den pågående revideringen kommer att omfatta åren 2022–2033. I samband med revideringen pågår också en strategisk miljöbedömning (SMB) för att integrera hållbarhetsaspekter i planprocessen på bästa sätt. SMB är ett lagstadgat verktyg för att integrera hållbarhetsaspekter i planering och beslutsfattning under framtagandet av planer och program som väntas ha en betydande miljöpåverkan. Eftersom regionala infrastrukturplaner förväntas ha betydande miljöpåverkan ska en SMB tas fram i samband med planprocessen, vilket Region Västernorrland gör. Det övergripande syftet med fallstudien i Region Västernorrland är att bidra med en djupare förståelse och kunskap om hur regioner på bästa sätt kan arbeta med SMB i samband med framtagandet av en regional infrastrukturplan.  Resultatet av studien visar att Region Västernorrland har utvecklat sitt arbete med SMB till en mer strategisk process jämfört med föregående planeringsprocess. De har tagit med sig erfarenheter gällande till exempel dokumentation och att säkerställa att deltagarna får relevant grundkunskap inför processen. Regionen är förändringsbenägna och vill utveckla sitt arbete med SMB, trots detta upplevs processen som svår eftersom det inte finns någon vedertagen vägledning för en strategisk process. Förhoppningen med en mer strategisk process, där miljöbedömningen startar tidigt i planprocessen, är att den kommer kunna påverka planen i en större utsträckning än tidigare.  Resultatet visar att det finns utvecklingspotential inom regionen men även nationellt. Inom branschen rekommenderas att ta fram en vägledning för hur en SMB kan tas fram som inte baseras på den specifika miljöbedömningens metod och att det skapas en plattform för att utbyta erfarenheter. Vidare rekommenderas regionen att besluta om ett överordnat mål för att förenkla hantering av konflikter mellan mål. För att bidra med viktig kunskap till nästa process, rekommenderas det att både små och stora beslut dokumenteras i en beslutslogg och att det sker en strukturerad erfarenhetsåterföring i slutet av processen. / The system between humankind and the environment is key in the work towards sustainable development, and the aspects of ecological, social, and economic sustainability. The proportions of these aspects are not equal, as it has been shown that ecological sustainability is the foundation for social and economic sustainability. A decrease in greenhouse gas emissions is a necessity to limit the impacts on the climate, a change in approach will be essential in e.g., the transport sector. The emissions from the transport sector must start decreasing by a log and at a faster pace to reach the goal of essentially zero emissions by 2045.  The region of Västernorrland in Sweden started the process of revising the current transport plan during the spring of 2021. The transport plan contains national investments in regional transportation infrastructure e.g., investments in roads and railways. The plan is revised every fourth year and the revised plan will cover the years 2022-2033. In connection to the revision a strategic environmental assessment (SEA) was conducted to integrate sustainability aspects to the process. SEA is in Sweden compulsory by law as a tool to integrate sustainability aspects into the planning process and the decision making for plans and programs that are expected to have a significant environmental impact. As the regional transportation plan is expected to have significant environmental impact, an SEA needs to be conducted along with the revision process of the transportational plan, as the region of Västernorrland does. The aim of this case study is to contribute with a deeper understanding and knowledge of how regions can work with SEA in relation to the revision of regional transportation plans.  The results of the study show that Region Västernorrland have developed their work with SEA towards a more strategic process, compared to the previous revision process. They have developed their work with documentation of the process and ensured they provide relative knowledge to the participants of the process in advance. The region is inclined to change and develop their work with SEA, however, do the process come across as difficult due to that there are no established guidance for the strategic process. The expectation with a more strategic process is that the assessment will start earlier in the planning process and result in a greater influence on the plan than previously. The results also show that there is an opportunity for development within the region but also nationally. A recommendation is to develop a guide that describes and exemplifies how the process for SEA can be performed in a strategic way and create a platform that enables experience exchange. Further it is recommended to decide on a superior goal to simplify when goals are conflicting, this would help in the process of handling these conflicts. Also, to document all decisions in a structured decision log and ensure that there is a structured process to incorporate experience from previous processes.
57

A comparison of integrated transport and spatial planning instruments : a case study of the Eden district municipality, Hermanus local municipality and Cape Town metropolitan areas / Jessica Hendrieka Page

Page, Jessica Hendrieka January 2012 (has links)
In the field of city planning, a growing need exists for the integration of spatial development with transportation planning instruments. This study identifies issues related to the definition, evaluation and implementation of the integration of sustainable development and sustainable transportation within three types of municipalities. Significant issues that are explored include the various definitions of integration; the range of issues considered under notions of integration; the diverse perspectives on, and criticism of development and transportation integration analysis, as well as approaches to evaluating integration and transportation impacts on development. Furthermore, the study reports on the goals of each municipality, specifically with reference to sustainable public transportation decision-making; approaches to sustainable transportation, automobile dependency; land use; and finally, on sustainable transportation and development integration solutions. Approaches to spatial development used to focus on the organisation of land use issues, but this field is increasingly defined more broadly to include economic and social welfare, quality of human health/life and environmental integrity. From a sustainability perspective, a narrow definition of sustainable transportation tends to favour individual technological solutions, while a broader definition tends to favour more integrated solutions, including improved travel choices, economic incentives, institutional reforms, land use changes as well as technological innovation. Integration focuses on the teamwork required between the relevant departments as well as between levels or spheres of government, and often entails the implementation of nodal-corridor approaches. Sustainability planning may require changing the way people think about solutions to transportation problems in the future. The literature survey (Chapter 2) addresses a number of salient concepts, namely transportation and spatial development integration, public transportation and its orientated development, nodal-corridor development, as well as environmental and development relationships. Furthermore, an investigation into the legislative frameworks and policies is presented with emphasis on spatial development, transportation plans and node-and-corridors development (Chapter 3). This is followed in Chapter 4 by a report on an investigation into, and interviews held with representatives from the three municipalities (Hermanus local municipality, Cape Town metropolitan municipality and Eden district municipality) with reference to the integrated transportation plans (ITP) and spatial development frameworks (SDF) of these municipalities. This section reflects the opinions of relevant role-players regarding the central aspects of this study. Chapter 5 presents a summary of the study as well as a number of conclusions. In this chapter, planning recommendations are provided with the aim of advising municipalities on possibilities for the integration of sustainable transportation plans and spatial planning / development instruments. / Thesis (M.Art. et Scien. (Urban and Regional planning))--North-West University, Potchefstroom Campus, 2012
58

Transporteffektivitet i avskilda transportsystem med hänsyn till säsongsvariation / Transport efficiency in secluded transport systems considering seasonality

Moberg, Olivia, Marke, Jennie January 2017 (has links)
Denna kandidatuppsats behandlar förslag på hur transporteffektivitet kan ökas med hänsyn tillsäsongsvariation i ett avskilt system. Ämnesområdet för uppsatsen är distribution och logistik.Uppsatsen har utförts i samarbete med Orust Kretsloppsakademi, Orust kommun och företag iOrust kommun.I syfte att ge förslag på hur transporteffektiviteten kan ökas i Orust kommun har olika sätt attutforma ett transportsystem studerats och utvärderats i termer av de fyraeffektivitetsvariablerna tid, kostnad, flexibilitet och miljö.Det avskilda system tillika avgränsning för uppsatsen som har studerats är vägtransporterinom Orust kommun. Det innebär att transporter till och från Orust kommun är exkluderadefrån studien. Uppsatsen inleddes med att studera teori kring de fyra effektivitetsvariablerna,transporteffektivisering och transportplanering. Därefter utformades en enkät som användessom grund och diskussionsunderlag till datainsamlingen. I enkäten ställdes frågor kringmarknadsvariation, flexibilitet, ledtider, samlastning samt möjligheter och begränsningar vidsamlastning. Enkäten besvarades av totalt 19 lokala företag. Komplettering av enkäten ochytterligare diskussion samlades in i form av mailintervjuer. Resultatet visade att det fannsutmaningar och hinder i arbetet att ge förslag till att öka transporteffektiviteten i Orustkommun. Det framkom ur svaren att tid var den effektivitetsvariabel som var av störst vikt närdet togs beslut om transporter inom Orust kommun. Av de olika sätt att utforma etttransportsystem på som presenterades var direkttransporter det alternativ som var mesttidseffektivt. De huvudsakliga nackdelarna med direkttransporter var att kostnaden blev högreoch miljöpåverkan större. Av denna anledning valde gruppen att kombinera två olikatransportupplägg för att hitta en så optimal lösning som möjligt utifrån avgränsningarna.Kombinationen som föreslogs var direkttransporter och mjölkrunda. Fördelarna medmjölkrunda är detsamma som nackdelarna hos direkttransporter. Kombinationen ger därmeden möjlighet för avsändare och mottagare att överväga vilken av de fyraeffektivitetsvariablerna som är viktigast utifrån enskild situation och typ av vara eller godsoch blir på så sätt situations- och företagsanpassat. Under sommartid då befolkningen ökar tillföljd av turism så tillåts företagen genom att kombinera de två transportsätten att anpassatransporterna till situationen på vägarna. Kombinationen tappar sitt syfte om direkttransporteranvänds betydligt mer än mjölkrunda.Projektgruppen stötte under arbetets gång på utmaningar med validitet och reliabilitet vilkethar diskuterats under avsnittet diskussion. / This bachelor thesis examines present suggestions for increase of transport efficiencyconsidering seasonality in a secluded system and subject area of the thesis is distribution andlogistics. The thesis was conducted in cooperation with Orust Kretsloppsakademi, OrustCounty and local companies on Orust.Different ways to design a transport system in consideration to the four efficiency variablestime, cost, flexibility and environment was evaluated with the purpose to increase thetransport efficiency. The studied system was road transport within Orust County, this was alsoone of the delimitations. It means that transports going outside of Orust County or arriving toOrust were excluded from the thesis. It all started with studying the theory of the efficiencyvariables, transport efficiency and transport planning, then a survey was designed to use asbase and discussion for the data collection. The purpose of the survey was to investigate thecurrent market variation, flexibility, lead times consolidation and identify possibilities as wellas challenges. The survey was answered by 17 local companies. Further data collection wascollected in terms of interviews. The result from the survey showed that there were somechallenges in designing an efficient transport system. The responses also showed that timewere the most critical variable when it came to local transport. Among the presented transportsystems, direct transports were the most time effective choice. However it increased thenegative impact on costs and the environment significantly. For this reason a combination oftwo different transport planning options was presented. The presented resolution was directtransports in combination with milk runs. The advantages with milk runs are equal to thedisadvantages with direct transport. Therefore the combination give the possibility for theshipper and consignee to make a tradeoff between time and flexibility and environment andcost based on the current shipping needs for specific goods at a specific time. During summerwhen the loads and passability on the roads increases due to tourism the combination of directtransports and milk runs can be used to adjusted to the situation on the roads. Thecombination loses its purpose if the direct transport is used more frequently than the milk run.The project group encountered some issues with validity and reliability which is discussed inthe discussion chapter of the thesis.
59

Direct Demand Estimation for Bus Transit in Small Cities

Nathaniel J Shellhamer (6611465) 10 June 2019 (has links)
<div> <p>Public transportation is vital for many people who do not have the means to use other forms of transportation. In small communities, transit service is often limited, due to funding constraints of the transit agency. In order to maximize the use of available funding resources, agencies strive to provide effective and efficient service that meets the needs of as many people as possible. To do this, effective service planning is critical.</p> <p> </p> <p>Unlike traditional road-based transportation projects, transit service modifications can be implemented over the span of just a few weeks. In planning for these short-term changes, the traditional four-step transportation planning process is often inadequate. Yet, the characteristics of small communities and the resources available to them limit the applicability of existing transit demand models, which are generally intended for larger cities.</p> <p> </p> <p>This research proposes a methodology for using population and demographic data from the Census Bureau, combined with stop-level ridership data from the transit agency, to develop models for forecasting transit ridership generated by a given geographic area with known population and socioeconomic characteristics. The product of this research is a methodology that can be applied to develop ridership models for transit agencies in small cities. To demonstrate the methodology, the thesis built ridership models using data from Lafayette, Indiana.</p> <p> </p> <p>A total of four (4) ridership models are developed, giving a transit agency the choice to select a model, based on available data and desired predictive power. More complex models are expected to provide greater predictive power, but also require more time and data to implement. Simpler models may be adequate where data availability is a challenge. Finally, examples are provided to aid in applying the models to various situations. Aggregation levels of the American Community Survey (ACS) data provided some challenge in developing accurate models, however, the developed models are still expected to provide useful information, particularly in situations where local knowledge is limited, or where additional information is unavailable.</p> </div> <br>
60

Modelos e métodos para estudos de configuração de redes logísticas. / Models and methods for the supply chain network design.

Guazzelli, Cauê Sauter 23 April 2018 (has links)
Este trabalho trata do problema de configuração de redes logísticas, em que são consideradas como principais decisões a quantidade e a localização de instalações logísticas e a definição da alocação de clientes às instalações. Mais especificamente, o trabalho considera um processo típico de configuração de redes logísticas que se vale de modelos discretos de otimização e a tomada de decisão com base nos resultados. O objetivo da tese é propor modelos e métodos capazes de dar suporte às etapas fundamentais deste tipo de estudo. Inicialmente são propostos métodos para a seleção de locais candidatos considerados nos modelos de localização. Os métodos se valem de informações sobre a distribuição dos pontos de demanda ao longo da rede para a obtenção dos candidatos a instalação e são avaliados por meio de sua aplicação a dois conjuntos de instâncias da literatura científica e comparação de tempos de resolução e de valores da função objetivo. Os resultados mostram que o tempo de resolução foi reduzido, na média, em 57% e os gaps das funções objetivo resultantes vale menos que 0,16% em comparação com os modelos que consideram todos os pontos de demanda como candidatos. Adicionalmente, também foram propostos métodos capazes de obter soluções alternativas de qualidade para problemas de localização que podem ser comparadas a fim de fornecer mais subsídio para a tomada de decisão. Os métodos são capazes de obter as K melhores soluções de problemas de localização e são avaliados por meio de sua aplicação a 215 instâncias da literatura científica. Além disso, a abordagem proposta permitiu a análise de resultados nunca antes obtidos para um problema muito estudado: as K melhores soluções do problema de localização de instalações capacitadas com custo fixo. Duas características principais foram identificadas: a quantidade de instalações é estável - em 99% das instâncias testadas o desvio padrão da quantidade de instalações nas 20 melhores soluções de cada instância é menor que um - e grande parte das instalações que fazem parte da solução ótima de cada instância também faz parte da maior parte das 20 melhores soluções. A partir de tais conclusões, o trabalho investiga algumas propriedades gerais de problemas de localização e apresenta uma análise topológica das 215 instâncias utilizadas, com base em indicadores propostos. Por fim, três tipos de modelos de redes neurais capazes de identificar relações entre os valores dos indicadores das instâncias e os valores das variáveis resposta associadas às melhores soluções são aplicados e avaliados. A abordagem consiste em comparar o tempo de resolução e o valor da função objetivo de modelos cujos espaços de soluções viáveis são reduzidos com base nos resultados obtidos pelas redes neurais. Os resultados mostram que é possível utilizar tal abordagem para melhorar o processo de configuração de redes logísticas, seja na etapa de construção dos modelos seja proporcionando mais subsídios para a tomada de decisão. / This thesis deals with the supply chain network design problem (SCND) that aims to find the optimal location of facilities and the allocation of customers to each facility. The work considers a typical process of SCND in which discrete optimization models are run and its results are used in the decision making. The goal of the thesis is to propose models and methods to support the stages of this type of planning process. Initially, methods for the selection of candidates considered in the localization models are proposed. The methods consider the distribution of the demand points throughout the network to obtain the candidates and are evaluated by their application to two sets of scientific literature instances and comparison of computational times and objective function values. The results show that the average computational time has been reduced by 57% and the resulting objective function gaps are less than 0,16% compared to the solutions obtained by the models that consider all the demand points as candidates. In addition, the thesis present methods capable of obtaining high-quality alternative solutions to location problems that can be compared in order to provide better support for decision making. The methods obtain the K-best solutions of location problems and are evaluated by their application to 215 instances of the scientific literature. In addition, the proposed approach allowed the analysis of results never before obtained for a well-studied problem: the best solutions of the capacitated fixed cost facility location problem. Two main insights were identified: the number of facilities is stable - in 99% of the tested instances the standard deviation of the number of facilities in the 20 best solutions of each instance is less than one - and most of the selected facilities in the optimal solution of each instance is selected in most of the 20 best solutions as well. Based on these conclusions, the work investigates some general properties of localization problems and presents a topological analysis of the 215 instances, based on proposed indicators. Finally, three types of neural network models capable of identifying relations between the instances indicators and the values of the variables of the best solutions are applied and evaluated. The approach consists in comparing the computational time and the objective function value of models whose feasible solution spaces are reduced based on the results obtained by the neural networks. The results show that it is possible to use such approach to improve the SCND process, either at the construction stage of the models or by providing more information for the decision making.

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