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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.
41

Energi- och miljövinster med ett bygglogistikcenter i Norra Djurgårdsstaden : Förslag på metod för utvärdering / Energy efficiency and environmental benefits of the construction consolidation center at Stockholm Royal Seaport : A proposed method of evaluation

Fröjd, Anna January 2015 (has links)
I Norra Djurgårdsstaden i Stockholm pågår ett stort stadsutvecklingsprojekt där det planerats för ungefär 12 000 nya bostäder, 35 000 arbetsplatser och 600 000 kvadratmeter kommersiell yta. För att koordinera alla transporter av byggmaterial in till området, samt hantera avfallstransporter ut ur området, har Stockholms stad etablerat ett bygglogistikcenter vars mål bland annat är att reducera antalet transporter. Syftet med detta examensarbete har varit att ta fram en metod för utvärdering av potentiella miljöeffekter med bygglogistikcentret i Norra Djurgårdsstaden. Examensarbetet har tittat på byggtransportlogistik ur ett livscykelperspektiv för jämförelse mellan två olika scenarion, då ett bygglogistikcenter finns (scenario 1) respektive då ett sådant inte finns (scenario 2). De parametrar som ingått är partiklar och energianvändning samt CO2, NOx och SO2. Två olika beräkningsverktyg har jämförts och valet föll på ett verktyg från NTM, Nätverket för Transporter och Miljön. En genomgång av vilken information som erfordras för att göra beräkningar har gjorts och för att undersöka tillgången till dessa data har ett antal intervjuer samt en workshop genomförts med olika aktörer, både inom Norra Djurgårdsstaden men också utifrån. Andra saker som diskuterades var aktörernas syn på bygglogistikcentret, vad som kan förbättras med det samt hur själva utfallet av en utvärdering skulle kunna förbättras, exempelvis genom styrning i upphandlingsprocessen. Intervjuer och workshop har också varit viktiga i syfte att förankra den föreslagna utvärderingsmetoden hos aktörerna själva. Under intervjuer och workshop har det bland annat framkommit en del konstateranden och några förslag till förbättringar. Exempelvis sades att logistikfrågor lyfts upp enbart genom att bygglogistikcentret finns och att den största förbättringen med bygglogistikcentret anses vara att framkomligheten är mycket bättre än vad den annars hade varit. En annan sak som de flesta var eniga om var att krav i upphandling bör ställas så tidigt som möjligt för att de ska kunna få så stor effekt som möjligt. För att göra en utvärdering krävs data om alla olika transporter och för varje transporttyp behövs information inom tre olika kategorier: fordonet, lasten samt själva körvägen. Eftersom alla data inte finns tillgängliga idag kommer en del antaganden att behöva göras, hur många beror på när i tiden utvärderingen ska göras och hur noggrann den ska vara. Om en utvärdering ska göras snarast rekommenderas att ett antal manuella mätningar genomförs men för att utvärderingar ska kunna göras kontinuerligt föreslås att en del åtgärder vidtas för att automatisera insamlingen av data. Det rekommenderas också att en känslighetsanalys av erhållna mätvärden görs för bedömning av vilka data som är i störst behov av ökad noggrannhet för att utvärderingens tillförlitlighet ska öka. Beroende på vad en sådan analys visar ges förslag på några olika åtgärder som kan vidtas, såsom att montera kameror vid grindpassager för information om passerande fordon eller att installera datorer i vissa fordon för att få information om körbeteende. / In the eastern part of Stockholm a major urban development project is taking place. It is called Stockholm Royal Seaport and until the year 2030 approximately 12,000 new homes, 35,000 workplaces and 600,000 square meters of commercial areas will be added to the area. The project has been given a very ambitious environmental action program and as a part of that the City of Stockholm has established a logistics center in the area. The logistics center is supposed to coordinate all transports of building material and handle the waste during the construction phase. One objective with the logistics center is to reduce the amount of transports and thereby also the generated emissions and the use of energy. The aim of this thesis has been to develop a methodology for evaluating the potential environmental impacts related to the logistics center in the Stockholm Royal Seaport. The evaluation method is able to compare the effect, from a life cycle perspective, from construction transports in two different scenarios, scenario 1 where there is a logistics center and scenario 2 where there is not. The chosen parameters are CO2, NOx, SO2, particulate matter and energy usage. Two different tools for computing values for the chosen parameters have been compared and the selected one is developed by NTM, the Network for Transport Measures. After the selection an investigation of input data required to use the tool was performed. A number of interviews were conducted and a workshop was organized with various representatives, mainly people working with construction or transportation in the Stockholm Royal Seaport. The things discussed during the interviews and the workshop were, among other things, the availability of required data, the interviewees opinions about the logistics center and their suggestions for improvements that can be done, both at the center itself, but also for example in the procurement process. Another purpose for the interviews and the workshop was to anchor the methodology with the various representatives. A direct result from the interviews and the workshop has been some proposals for improvement, for example that requirements in the procurement process should be presented at an early stage to be able to be as effective as possible. Some of the interviewees pointed out that logistic issues are highlighted simply by the existence of the logistics center. There are a couple of different transport routes within the area, as some deliveries are allowed directly into the construction sites, whereas some have to pass the logistics center to unload the freight, all depending on the amount of freight to a specific site. Staff at the logistics center will then consolidate the deliveries to the construction sites into one vehicle. They also collect the generated waste, which they handle at the center before it is transported to an external retrieval plant. The logistics center also utilizes a vehicle used for inspections of the traffic and deliveries within the area. All of the above mentioned types of transportations are included in the thesis. An evaluation of the effects of the logistics center requires data about all types of transportation, within three different categories: the vehicle, the load and the actual route. Since all required data is not available today some assumptions have to be made, how many and which depends on the requested accuracy of the evaluation and when it is to be performed. If an evaluation is to be performed given the current conditions it is recommended that a number of manual measurements are carried out to collect data which was not available at the time being, however, if evaluations are to be done continuously it is suggested that the retrieval of data is as automated as possible. It is also recommended to do a sensitivity analysis of the data retrieved from the measurements to assess the impact from certain data on the chosen parameters. The amount of impact helps determine which data to refine in order to increase the accuracy of the evaluation. Depending on what the analysis shows the thesis gives suggestions for actions such as installing cameras at gates to the construction sites and/or the logistics center or to install computers in vehicles to obtain data on driving behavior.
42

OPTIMERING AV LEVERANSER OCH LAGERHÅLLNING FÖR SKANSKA : En komparativ studie av lagerhållning och JIT-leveranser samt en utredning av optimal materialplacering på lager

Dahlén, Anna, Öhman, Angelica January 2019 (has links)
Inom byggindustrin är det svårt att skapa standardiserade logistikprocesser eftersom det vid varje nytt bygge även skapas en ny organisation. Förutsättningarna skiljer sig även mellan olika byggen, vilket försvårar ett förbättringsarbete. Skanska Väg och Anläggning Norr fick under 2017 uppdraget att bygga om Vasaplan i centrala Umeå, och i september 2018 stod projektet klart. Ombyggnationen var i det stora hela ett mycket lyckat projekt, men efter färdigställandet av projektet har problem angående materialtillgång identifierats. Syftet med arbetet är att undersöka hur leveranser till en byggarbetsplats kan optimeras samt hurvida ett mellanlager kan underlätta hanteringen av leveranserna till byggarbetsplatsen. En jämförelse har gjorts där det har undersökts ifall det är mer lönsamt att använda sig av lagerhållning, eller endast av JIT-leveranser. Förhoppningen är att arbetet kan bidra till att Skanska i framtiden får ett mer standardiserat tillvägagångssätt vid planering av leveranser till byggarbetsplats av material som kräver liknande lagerhållning och transport som granithällar. För att lösa detta har två matematiska modeller använts; Anläggningslokaliseringsproblemet (ALP) samt en matematisk modell som optimerar placering av material på en lageryta. Två stycken produktionsflödesmodeller, JIT och EOQ, har även använts i beräkningarna. Resultatet från produktionsflödesmodellerna, JIT och EOQ, visar att JIT-leveranser med hjälp av en omlastningscentral alltid är den mest kostnadseffektiva lösningen då lageryta är en direkt kostnad för Skanska. I de fall lager inte är en direkt utgift för Skanska så rekommenderar den matematiska modellen för ALP en optimal användning av de lager som är tillgängliga. / For every new construction project, a new organisation is created. It is therefore a challenge for the construction industry to create standardized logistic processes. In addition, different construction projects have different traits, which results in further challenges for improvement efforts for the construction logistic processes. In 2017 Skanska Väg och Anläggning Norr did the reconstruction of Vasaplan in the central of Umeå, and in September 2018 the reconstruction project was done. The reconstruction was in its entirety a very successful project, however when the project was finished problems regarding material supply were identified. The aim of this paper is to analyze how deliveries to a construction site can be optimized and whether storage spaces can aid in the handling of deliveries to the construction site. A comparison has been made between storing material and using JIT-deliveries. The hope is to help Skanska in developing a more standardized approach when it comes to planning the deliveries of materials that has similar storage and transport conditions as the slabs of granite used. To solve this two mathematical models have been used; Facility location problem and a mathematical model that optimizes the placement of materials in a storage space. Two production flow models, JIT and EOQ, were also used when performing the calculations. The result from the production flow models, JIT and EOQ, show that JIT deliveries are always the most cost effective solution when storage space is a direct cost for Skanska, when used together with a logistics center. However, when storing is no extra expense for Skanska, the mathematical model for the Facility location problem suggests a optimal use of the storage spaces that are available.
43

A systematic approach to assess the relocation of the business centres to a logistics platform: A case study on DHL Freight AB (Sweden)

Rozario, Jewel Augustine, Hamid, Osman Abdelkader January 2018 (has links)
The relocation of logistic companies’ from the inner centres to the logistic platforms significantly affects both the supply chain management and the urban sustainability development. Recently the concept of city logistics and intermodality has received a significant attention from both academics and decision makers. City logistics play a pivotal role to ensure the liveability of urban areas but, in parallel, urban freight transport also has a significant effect on the quality of life in the urban settings. Optimization of urban freight transportation have an important input in the context of sustainability and liveability of cities and urban areas reducing traffic congestion, decreasing road accidents, alleviating CO2 emissions and noise impacts. The purpose of this thesis is to evaluate the relocation of a case logistics company from the city centre to a suburban area. To do this, a wide range of literature reviews pertaining the influence of peripheral logistics platform on the city sustainability were investigated. It seems that there are not well-defined models which can make a comprehensive and quantitative assessment in the context of sustainability for the relocation of business premises. Further investigation was done by conducting a case study on DHL, field observation of traffic flow. Based on all the collected information from the relevant sources, a mixed methods research was applied including a qualitative approach and a quantitative approach. A systematic approach was therefore developed in the context of sustainable development which can be used as an assessment tool for the major factors that enlighten the decision makers to consider the relocation of the logistics companies. A systematic approach was developed by this thesis which facilitates the assessment of key factors that impact the relocation decision in the context of all the three sustainable aspects: economic, social and environmental development. These impacts represent traffic congestion, time and distance of transportation, emission, cost optimization and transport mobility.
44

Impensée mais structurante, refoulée mais exhibée : la mobilité urbaine des marchandises / Urban freight mobility : a paradox and a challenge

Gardrat, Mathieu 21 September 2017 (has links)
Encore méconnu il y a une trentaine d’années, le transport de marchandises en ville connaît aujourd’hui un essor scientifique incontestable, sous la tutelle d’instances nationales et internationales. Le sujet émerge aujourd’hui comme un enjeu d’autant plus fort que les modes de consommation et de gestion logistique restructurent les flux de biens et impactent la durabilité des villes. Pour autant, il semblerait que l’aménageur peine à se saisir à l’échelle locale de cette nouvelle thématique. Elément essentiel au fonctionnement du système urbain, le transport de marchandises reste ainsi un élément généralement ignoré par les décideurs publics, s’il n’est pas vécu comme une manifestation néfaste de l’activité urbaine.Dans cette thèse nous examinons, à l’échelle des collectivités territoriales l’intégration d’une thématique encore considérée comme faiblement structurante pour l’aménageur public. Si le transport de marchandises en ville a nécessité au début des années 1990 une conceptualisation différente du transport de fret interurbain, ce sujet exige également une adaptation spécifique aux enjeux que se pose l’aménageur. En ce sens nous, discutons les bases conceptuelles permettant de passer d’une approche technique et statistique du transport à la mobilité urbaine des marchandises pour englober les dynamiques du système urbain des « marchandises ». A travers neuf agglomérations françaises, nous confrontons les dispositifs stratégiques d’aménagement aux spécificités de la mobilité urbaine des marchandises et les conflits et incohérences qui en découlent. Nous développons par la suite le cas lyonnais pour illustrer les dynamiques et interactions territoriales complexes qui sous-tendent la mobilité urbaine des marchandises et l’évolution ainsi que les limites de la prise en compte de cette thématique. Enfin, pour discuter les effets de ces modes d’(in)action sur l’environnement urbain nous détaillons le processus d’intégration opérationnelle de la mobilité des marchandises dans deux opérations d’aménagement emblématiques de la ville de Lyon, le projet Lyon-Confluence et la rue Garibaldi.Malgré l’existence d’outils de mesure et d’action, nous montrons que la mobilité urbaine des marchandises est une thématique encore illégitime, en conflit avec le processus d’aménagement classique. Dans ce contexte les techniciens spécialistes du sujet se retrouvent marginalisés du processus d’aménagement mais servent toutefois d’alibi technique et politique pour afficher les capacités de réflexions de la collectivité sur une thématique complexe. / Still widely unexplored thirty years ago, urban freight transport is now undergoing an indisputable scientific development under the tutelage of national and international institutions. This subject now emerges as a substantial issue since consumers’ behaviours and supply chain management evolutions strongly impact cities’ sustainability. However, it seems that urban planners hardly take this new topic into account on a local level. Although it is an essential function of the urban system, freight transport remains widely unregarded by public decision makers, when it is not considered as a negative consequence of urban activity.This thesis focuses on the integration of a subject envisioned as poorly structuring for urban planners, studied here at the local authorities’ level. In the 1990s the necessity emerged for urban freight transport to be conceptualised in a way that differed from interurban freight transport. We now also consider that this subject needs to be specifically adapted to suit urban planners’ issues and we discuss the conceptual bases necessary to shift from a technical and statistical approach of transport to a view of urban freight mobility encompassing the dynamics of the “urban freight” system. Relying on the examples of nine French conurbations, we then confront urban planning policies to the specificities of urban freight mobility and describe the resulting conflicts and inconsistencies. We then develop the case of Lyons to illustrate the complex territorial dynamics and interactions underlying urban freight mobility and provide an analysis of how the actors’ awareness of this topic has evolved and to what extent it can be raised. Finally, in order to study the effects the (in)actions of city planners on urban environment we detail the process of integration of freight mobility through two urban development operations in Lyons, the “Lyon Confluence” project and the Garibaldi street project.Despite the existence of measuring and action tools, we show that urban freight mobility is still an illegitimate subject, at odds with mainstream urban planning. In this context, freight specialists in local authorities are largely kept away from the planning process, but are exposed and used as an alibi to demonstrate the capacity of public authorities to work on a complex subject.
45

INVESTIGAÇÃO DAS PRÁTICAS DE LOGÍSTICA URBANA EM CIDADES BRASILEIRAS

Dias, José Maria 29 May 2017 (has links)
Submitted by José Dias (jmdiassor@gmail.com) on 2017-12-06T15:37:50Z No. of bitstreams: 2 Dissertação JMDias UFSCar_So v.final.pdf: 1930492 bytes, checksum: cf7a9d0a9b17e5ea00075d652b21d2ce (MD5) Carta comprovante.pdf: 330278 bytes, checksum: 7ec98b5d36367e44412de8af04a35377 (MD5) / Approved for entry into archive by Milena Rubi ( ri.bso@ufscar.br) on 2017-12-07T12:03:28Z (GMT) No. of bitstreams: 2 Dissertação JMDias UFSCar_So v.final.pdf: 1930492 bytes, checksum: cf7a9d0a9b17e5ea00075d652b21d2ce (MD5) Carta comprovante.pdf: 330278 bytes, checksum: 7ec98b5d36367e44412de8af04a35377 (MD5) / Approved for entry into archive by Milena Rubi ( ri.bso@ufscar.br) on 2017-12-07T12:03:40Z (GMT) No. of bitstreams: 2 Dissertação JMDias UFSCar_So v.final.pdf: 1930492 bytes, checksum: cf7a9d0a9b17e5ea00075d652b21d2ce (MD5) Carta comprovante.pdf: 330278 bytes, checksum: 7ec98b5d36367e44412de8af04a35377 (MD5) / Made available in DSpace on 2017-12-07T12:03:50Z (GMT). No. of bitstreams: 2 Dissertação JMDias UFSCar_So v.final.pdf: 1930492 bytes, checksum: cf7a9d0a9b17e5ea00075d652b21d2ce (MD5) Carta comprovante.pdf: 330278 bytes, checksum: 7ec98b5d36367e44412de8af04a35377 (MD5) Previous issue date: 2017-05-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / With the growth of urban population and the increase of the vehicle fleet, Brazilian cities face urban dysfunction problems like congestion, environmental pollution, car accidents among others and its consequences are felt by citizens. With the institution of the PNMU - Política Nacional de Mobilidade Urbana (National Urban Mobility Policy), Brazil has sought to direct the planning of solutions for the urban transportation of people and cargo in an integrated and sustainable way The literature shows a lack of national research focused on planning and local policies of urban freight and better understanding of the authorities on the freight transportation and supply chains, for decision-making on policy and planning Urban Freight Transport (UFT). The practices and concepts of City Logistics intend optimal solutions for goods handling issues in urban areas. In this context, the use of City Logistics (CL) practices in Brazilian cities was investigated. Therefore, the contents related to UFT and CL were analyzed in the PlanMobs – Planos de Mobilidade Urbana (Urban Mobility Plans) elaborated by these cities. Additionally was produced a data collection (survey research), with those responsible for the preparation/review of PlanMobs. This research identifies the resources used in the UFT planning, the CL practices adopted and the perceptions of the municipal authorities about the UFT and CL. The results showed that the LU is still neglected and appears not to be the focus of the authorities who have developed the PlanMob. The lack of local authorities’ specific skills, with the low use of planning resources makes it impossible to achieve the LU goals. / Com o crescimento da população urbana e o aumento da frota de veículos, as cidades brasileiras enfrentam problemas de disfunções urbanas como congestionamento, poluição ambiental, acidentes, cujas consequências são vivenciadas pelos cidadãos. Com a instituição da Politica Nacional de Mobilidade Urbana (PNMU), o Brasil procurou direcionar o planejamento de soluções para o transporte urbano de pessoas e cargas de forma integrada e sustentável. A literatura mostra a falta de pesquisas nacionais com foco no planejamento e políticas locais de frete urbano e de melhor entendimento das autoridades sobre o transporte de cargas e das cadeias de suprimentos, para a tomada de decisão sobre políticas e planejamento do Transporte Urbano de Cargas (TUC). As práticas e conceitos da Logística Urbana buscam soluções para a problemática da movimentação urbana de mercadorias. Neste contexto, investigou-se a utilização das práticas da Logística Urbana (LU) nas cidades brasileiras. Para tanto, foram analisados os conteúdos relativos ao TUC e LU nos Planos de Mobilidade Urbana (PlanMob) elaborados por estas cidades. Adicionalmente elaborou-se um levantamento de dados (pesquisa tipo survey), junto aos responsáveis pela elaboração/revisão dos PlanMobs. Esta pesquisa identifica os recursos utilizados no planejamento do TUC, as práticas de LU adotadas e as percepções das autoridades municipais sobre o TUC e a LU. Os resultados demostraram que a LU ainda é negligenciada e parece não ser o foco das autoridades que têm elaborado o PlanMob. A falta de competências específicas das autoridades locais, com a baixa utilização dos recursos para o planejamento impossibilita o alcance das metas da LU.
46

Planejamento urbano e transporte urbano de carga: investigação de modelos de integração e aplicação do modelo Freturb em um recorte urbano em São Paulo. / Urban planning and urban freight: integrated moddeling investigation and the application of Freturb Model in an urban area in the city of São Paulo.

Montmorency Silva, Thiago Canhos 16 June 2016 (has links)
A efervescência da cidade moderna somente é possível devido ao deslocamento contínuo de pessoas e mercadorias. A movimentação de bens é trivial para a realização das atividades comerciais, industriais e de prestação de serviços. Sua demanda, entretanto, é condicionada pelos padrões de uso e ocupação do solo e adensamento urbano. Esta pesquisa aborda aspectos da relação entre o transporte urbano de carga e a estruturação das áreas urbanas no Brasil. O principal objetivo é analisar a influência mútua entre a logística urbana e o uso e ocupação do solo no desenvolvimento de áreas urbanas no Município de São Paulo. Dessa forma, foram identificados, selecionados e analisados abordagens, metodologias e modelos aplicáveis à análise e proposição de diretrizes que integrem os condicionantes de desenvolvimento urbano e de transporte urbano de carga. Um modelo selecionado, o Freturb, foi aplicado em um recorte urbano do Município de São Paulo. Localizada na região de Santa Cecília e Higienópolis, a área de estudo foi modelada, primeiramente, de acordo com a sua configuração urbana atual e, em seguida, com as suas predições urbanas para os anos de 2025 e 2030, conforme os parâmetros urbanísticos do novo Plano Diretor Estratégico de São Paulo, em vigor desde 2014. Os resultados da modelagem foram abordados, qualitativamente, sob três categorias, que organizam parâmetros de planejamento e que se inter-relacionam no ambiente urbano: Aspectos do Uso e Ocupação do Solo, Aspectos da Logística e Aspectos do Tráfego Urbano. O trabalhou comparou, ainda, os resultados da configuração urbana atual do recorte urbano de São Paulo, com áreas urbanas francesas, selecionadas no Centro de Lyon e no 4o. Arrondissement de Paris. Essa comparação permitiu analisar a relação entre a empregabilidade e a densidade de movimentos da carga, nas três regiões urbanas. O estudo revelou que a área estudada em São Paulo necessita de mais movimentação de carga e exige mais do viário urbano e/ou é suprida por sistemas logísticos menos organizados, em relação às duas áreas francesas. Ainda, o porte e o perfil do estabelecimento podem incrementar o tempo de carga e descarga em uma área urbana. Finalmente, as predições urbanas, de 2025 e 2030, motivadas pelo novo Plano Diretor Estratégico do Município de São Paulo, permitiram avaliar e compreender os possíveis impactos do adensamento populacional e de empregos na demanda por transporte urbano de carga. E, verificar os possíveis impactos associados, tais como incremento em paradas em \"fila-dupla\" e ocupação viária por veículos de carga. / The effervescence of the modern city is only possible due to the continuous movement of people and goods. The movement of goods is trivial for of commercial, industrial and service activities. However, it is conditioned by the patterns of land use and urban density. This research approaches aspects of the relation between the urban freight transport and the structuring of urban areas in Brazil. The main objective is to analyze the mutual relationship among urban logistics and urban land use parameters on developing urban areas in São Paulo. Thus, applicable approaches, methodologies and models were identified, selected and analyzed, in light of their potential to support the integration of urban development and urban freight transport conditions. A selected model, the Freturb, was applied in an urban area in the city of São Paulo. Located in the region of Santa Cecilia and Higienopolis, the case study area was modeled, firstly, according to its current urban setting and then with their urban predictions for the years 2025 and 2030, according the new parameters of Master Plan of São Paulo, approved in 2014. The modeling results were classified and discussed accordingly to three aspects: Land Use Aspects, Logistics Aspects and Urban Traffic Aspects. The research also compared the results of the case study area located in São Paulo with other French urban areas, selected in the Center of Lyon and 4th. Arrondissement of Paris. Such a comparison allowed analyzing the relationship between the employability and the density of freight movements, in the three urban areas. The research revealed that the area in São Paulo requires more freight movement and urban road space and/or is supplied by less organized logistics systems, with regard to the latter two French areas. Also, the size and profile of the establishment can increase the loading and unloading time of operation in an urban area. Finally, the urban predictions, 2025 and 2030, motivated by the new Master Plan of São Paulo, allowed evaluating and understanding the possible impacts of population density and employment in demand for urban freight transport. And, they also allowed verifing the possible associated impacts, such as the increase in stops at \"double-park\" and road occupancy by goods vehicles.
47

Planejamento urbano e transporte urbano de carga: investigação de modelos de integração e aplicação do modelo Freturb em um recorte urbano em São Paulo. / Urban planning and urban freight: integrated moddeling investigation and the application of Freturb Model in an urban area in the city of São Paulo.

Thiago Canhos Montmorency Silva 16 June 2016 (has links)
A efervescência da cidade moderna somente é possível devido ao deslocamento contínuo de pessoas e mercadorias. A movimentação de bens é trivial para a realização das atividades comerciais, industriais e de prestação de serviços. Sua demanda, entretanto, é condicionada pelos padrões de uso e ocupação do solo e adensamento urbano. Esta pesquisa aborda aspectos da relação entre o transporte urbano de carga e a estruturação das áreas urbanas no Brasil. O principal objetivo é analisar a influência mútua entre a logística urbana e o uso e ocupação do solo no desenvolvimento de áreas urbanas no Município de São Paulo. Dessa forma, foram identificados, selecionados e analisados abordagens, metodologias e modelos aplicáveis à análise e proposição de diretrizes que integrem os condicionantes de desenvolvimento urbano e de transporte urbano de carga. Um modelo selecionado, o Freturb, foi aplicado em um recorte urbano do Município de São Paulo. Localizada na região de Santa Cecília e Higienópolis, a área de estudo foi modelada, primeiramente, de acordo com a sua configuração urbana atual e, em seguida, com as suas predições urbanas para os anos de 2025 e 2030, conforme os parâmetros urbanísticos do novo Plano Diretor Estratégico de São Paulo, em vigor desde 2014. Os resultados da modelagem foram abordados, qualitativamente, sob três categorias, que organizam parâmetros de planejamento e que se inter-relacionam no ambiente urbano: Aspectos do Uso e Ocupação do Solo, Aspectos da Logística e Aspectos do Tráfego Urbano. O trabalhou comparou, ainda, os resultados da configuração urbana atual do recorte urbano de São Paulo, com áreas urbanas francesas, selecionadas no Centro de Lyon e no 4o. Arrondissement de Paris. Essa comparação permitiu analisar a relação entre a empregabilidade e a densidade de movimentos da carga, nas três regiões urbanas. O estudo revelou que a área estudada em São Paulo necessita de mais movimentação de carga e exige mais do viário urbano e/ou é suprida por sistemas logísticos menos organizados, em relação às duas áreas francesas. Ainda, o porte e o perfil do estabelecimento podem incrementar o tempo de carga e descarga em uma área urbana. Finalmente, as predições urbanas, de 2025 e 2030, motivadas pelo novo Plano Diretor Estratégico do Município de São Paulo, permitiram avaliar e compreender os possíveis impactos do adensamento populacional e de empregos na demanda por transporte urbano de carga. E, verificar os possíveis impactos associados, tais como incremento em paradas em \"fila-dupla\" e ocupação viária por veículos de carga. / The effervescence of the modern city is only possible due to the continuous movement of people and goods. The movement of goods is trivial for of commercial, industrial and service activities. However, it is conditioned by the patterns of land use and urban density. This research approaches aspects of the relation between the urban freight transport and the structuring of urban areas in Brazil. The main objective is to analyze the mutual relationship among urban logistics and urban land use parameters on developing urban areas in São Paulo. Thus, applicable approaches, methodologies and models were identified, selected and analyzed, in light of their potential to support the integration of urban development and urban freight transport conditions. A selected model, the Freturb, was applied in an urban area in the city of São Paulo. Located in the region of Santa Cecilia and Higienopolis, the case study area was modeled, firstly, according to its current urban setting and then with their urban predictions for the years 2025 and 2030, according the new parameters of Master Plan of São Paulo, approved in 2014. The modeling results were classified and discussed accordingly to three aspects: Land Use Aspects, Logistics Aspects and Urban Traffic Aspects. The research also compared the results of the case study area located in São Paulo with other French urban areas, selected in the Center of Lyon and 4th. Arrondissement of Paris. Such a comparison allowed analyzing the relationship between the employability and the density of freight movements, in the three urban areas. The research revealed that the area in São Paulo requires more freight movement and urban road space and/or is supplied by less organized logistics systems, with regard to the latter two French areas. Also, the size and profile of the establishment can increase the loading and unloading time of operation in an urban area. Finally, the urban predictions, 2025 and 2030, motivated by the new Master Plan of São Paulo, allowed evaluating and understanding the possible impacts of population density and employment in demand for urban freight transport. And, they also allowed verifing the possible associated impacts, such as the increase in stops at \"double-park\" and road occupancy by goods vehicles.
48

Multi-attribute deterministic and stochastic two echelon location routing problems

Escobar Vargas, David 10 1900 (has links)
Les problèmes de localisation-routage à deux échelons (2E-LRP) sont devenus un domaine de recherche important dans le domaine de la logistique et de la gestion de la chaîne d'approvisionnement. Le 2E-LRP représente un problème d'optimisation dans les systèmes de distribution non dirigés, visant à organiser le transport de marchandises entre les plateformes et les clients par le biais d'installations intermédiaires appelées satellites. Ce problème implique de prendre des décisions simultanées concernant l'emplacement d'un ou deux niveaux d'installations (plateformes et/ou satellites) et de créer un ensemble limité d'itinéraires aux deux échelons afin de répondre efficacement à toutes les demandes des clients. Récemment, la communauté scientifique s'est intéressée de plus en plus à l'étude et à la résolution de problèmes plus réalistes. Cet intérêt provient de la reconnaissance du fait que les systèmes de distribution du monde réel sont caractérisés par une multitude de complexités et d'incertitudes qui ont un impact significatif sur l'efficacité opérationnelle, la rentabilité et la satisfaction des clients. Les chercheurs ont reconnu la nécessité d'aborder ces complexités et incertitudes pour développer des solutions pratiques et efficaces. Cette thèse comprend trois études différentes, chacune correspondant à un article de recherche autonome. Dans les trois articles, nous nous concentrons sur différents 2E-LRP riches qui comprennent plusieurs attributs en interaction. Ces variantes du problème sont appelées problèmes de localisation-routage à deux échelons et à attributs multiples (2E-MALRP). Pour analyser l'influence des incertitudes sur les solutions optimales et les processus de prise de décision, nous considérons à la fois les perspectives déterministes et stochastiques. Cette approche nous permet de mieux comprendre le comportement de ces problèmes complexes. Le premier document de recherche abordé dans cette thèse se concentre sur un problème de localisation-routage déterministe à deux échelons et à attributs multiples avec synchronisation de la flotte dans les installations intermédiaires (2E-MALRPS). Le cadre du problème comprend divers facteurs, notamment la demande de marchandises multiples dépendant du temps, les fenêtres temporelles, le manque de capacité de stockage dans les installations intermédiaires et la nécessité de synchroniser les flottes opérant à différents échelons. Dans le 2E-MALRPS, tous les paramètres, tels que les demandes des clients, les temps de trajet et les coûts, sont connus avec certitude. Dans cet article, nous introduisons le cadre du problème, présentons une formulation de programmation en nombres entiers mixtes et proposons un cadre de découverte de discrétisation dynamique comme méthode de résolution du problème. Le deuxième article de cette thèse traite du problème de localisation-routage à deux échelons en cas de demandes stochastiques et corrélées (2E-MLRPSCD). Contrairement au 2E-MALRPS, le 2E-MLRPSCD prend en compte les incertitudes liées aux demandes des clients, ainsi que la corrélation entre ces demandes. Nous formulons le problème sous la forme d'un modèle de programmation stochastique en deux étapes. Au cours de la première étape, des décisions sont prises concernant la conception des installations satellites, tandis qu'au cours de la deuxième étape, des décisions de recours déterminent la manière dont les demandes observées sont servies. Nous proposons une métaheuristique de couverture progressive comme méthode de résolution. Dans cette approche, nous incorporons deux structures de population dans le cadre de la couverture progressive. Ces structures renforcent la diversité des décisions de conception obtenues pour chaque sous-problème de scénario et fournissent des informations pertinentes pour améliorer la qualité de la solution. En outre, nous introduisons et comparons trois nouvelles stratégies différentes pour accélérer la recherche de l'espace de solution pour le problème stochastique. Finalement, le troisième article présenté dans cette thèse se concentre sur un problème de localisation-routage multi-attributs à deux échelons avec des temps de trajet stochastiques (2E-MALRPSTT). Le 2E-MALRPSTT combine un problème multi-attributs riche avec des éléments stochastiques, en particulier en considérant des temps de trajet stochastiques. Pour traiter le problème stochastique complet, un cadre de couverture progressive (PH) est proposé en s'appuyant sur les lignes directrices méthodologiques définies dans notre deuxième article pour le 2E-MLRPSCD. En outre, une heuristique basée sur la décomposition est introduite pour accélérer le cadre PH, et deux nouvelles stratégies d'agrégation sont présentées pour accélérer le processus de consensus concernant les décisions de la première étape. Les contributions présentées dans cette thèse couvrent divers aspects de la modélisation et des méthodologies de solution pour les 2E-MALRP riches, à la fois d'un point de vue déterministe et d'un point de vue stochastique. Les trois articles inclus dans cette thèse démontrent l'efficacité des approches proposées à travers des campagnes expérimentales étendues, mettant en évidence leur efficacité de calcul et la qualité des solutions, en particulier dans les cas difficiles. En abordant les aspects déterministes et stochastiques de ces 2E-MALRP, cette thèse vise à contribuer à l'ensemble des connaissances en optimisation de la logistique et de la chaîne d'approvisionnement, à répondre aux besoins importants de la littérature actuelle et à fournir des informations importantes pour les systèmes de distribution à deux échelons dans divers contextes. / The Two-Echelon Location-Routing Problems (2E-LRPs) have emerged as a prominent research area within the field of logistics and supply chain management. The 2E-LRP represents an optimization problem in undirected distribution systems, aiming to streamline freight transportation between platforms and customers through intermediate facilities known as satellites. This problem involves making simultaneous decisions concerning the location of one or two levels of facilities (platforms and/or satellites) and creating a limited set of routes at both echelons to effectively serve all customer demands. In recent years, there has been a growing interest among the scientific community in studying and solving more realistic problem settings. This interest arises from the recognition that real-world distribution systems are characterized by a multitude of complexities and uncertainties that significantly impact operational efficiency, cost-effectiveness, and customer satisfaction. Researchers have acknowledged the need to address these complexities and uncertainties to develop practical and effective solutions. This dissertation comprises three distinct studies, each serving as a self-contained research article. In all three articles, we focus on different rich 2E-LRPs that encompass multiple interacting attributes. These problem variants are referred to as two-echelon multi-attribute location-routing problems (2E-MALRPs). To analyze the influence of uncertainties on optimal solutions and decision-making processes, we consider both deterministic and stochastic perspectives. This approach allows us to gain insights into the behavior of these complex problem settings. The first research paper addressed in this thesis focuses on a deterministic two-echelon multi-attribute location-routing problem with fleet synchronization at intermediate facilities (2E-MALRPS). The problem setting encompasses various factors, including time-dependent multicommodity demand, time windows, lack of storage capacity at intermediate facilities, and the need for synchronization of fleets operating at different echelons. In the 2E-MALRPS, all parameters, such as customer demands, travel times, and costs, are known with certainty. In this paper, we introduce the problem setting, present a mixed-integer programming formulation, and propose a dynamic discretization discovery framework as the solution method to address the problem. The second paper in this thesis addresses the two-echelon multicommodity location-routing problem with stochastic and correlated demands (2E-MLRPSCD). In contrast to the 2E-MALRPS, the 2E-MLRPSCD takes into account uncertainties related to customer demands, as well as the correlation among these demands. We formulate the problem as a two-stage stochastic programming model. In the first stage, decisions are made regarding the design of satellite facilities, while in the second stage, recourse decisions determine how the observed demands are allocated and served. We propose a progressive hedging metaheuristic as the solution method. In this approach, we incorporate two population structures within the progressive hedging framework. These structures enhance the diversity of the design decisions obtained for each scenario subproblem and provide valuable insights for improving the solution quality. Additionally, We also introduce and compare three different novel strategies to accelerate the search for the solution space for the stochastic problem. Finally, the third paper presented in this thesis focuses on a multi-attribute two-echelon location-routing problem with stochastic travel times (2E-MALRPSTT). The 2E-MALRPSTT combines a rich multi-attribute problem setting with stochastic elements, specifically considering stochastic travel times. To address the complete stochastic problem, a progressive hedging metaheuristic is proposed building on the methodological guidelines defined in our second paper for the 2E-MLRPSCD. Furthermore, a decomposition-based heuristic is introduced to accelerate the PH framework, and two novel selection strategies are presented to expedite the consensus process regarding the first-stage decisions. The contributions presented in this thesis encompass various aspects of modeling and solution methodologies for rich 2E-MALRPs from both deterministic and stochastic perspectives. The three articles included in this thesis demonstrate the effectiveness of the proposed approaches through extensive experimental campaigns, highlighting their computational efficiency and solution quality, particularly in challenging instances. By addressing the deterministic and stochastic aspects of these 2E-MALRPs, this thesis aims to contribute to the broader body of knowledge in logistics and supply chain optimization, fill important gaps in the present literature and provide valuable insights for two-echelon distribution systems in diverse settings.
49

Das E-Lastenrad als Alternative im städtischen Wirtschaftsverkehr. Determinanten der Nutzung eines „neuen alten“ Fahrzeugkonzepts

Gruber, Johannes 05 March 2021 (has links)
Elektrifizierte Lastenfahrräder werden als ein Lösungsansatz für die wachsenden Herausforderungen des städtischen Wirtschaftsverkehrs gesehen. Fokus dieser Arbeit ist eine Abschätzung des Einsatzpotenzials dieses Fahrzeugkonzepts unter Betrachtung von konzeptionellen, verkehrlichen und wirtschaftlichen Aspekten. Als kumulative Dissertation enthält sie fünf Fachartikel, gruppiert zu drei Forschungsbeiträgen. Im ersten Forschungsbeitrag wird erörtert, wie erfolgversprechend das E-Lastenrad, eine Neuauflage des alten Konzepts Lastenfahrrad, in einem Markt mit ersten Anwendern (Kurierdienstleistung) ist. Die Auftragsstruktur im Stadtkuriergeschäft bietet ein substanzielles Marktpotenzial für E-Lastenräder, allerdings erschwert die Positionierung zwischen zwei etablierten Modi (Pkw und Fahrrad) den Markteintritt. Der zweite Teil der Analyse weitet den Blick auf alle Branchen und bietet eine strukturierte Beschreibung der verschiedenartigen Einflussfaktoren (Treiber und Hemmnisse), die auf die Lastenradnutzung im städtischen Wirtschaftsverkehr wirken. Als relevante Entscheidungskriterien konnten identifiziert werden: fahrzeugseitige Aspekte, Strukturen und Prozesse des adoptierenden Unternehmens, Einstellungen der Entscheider*innen, weiche Faktoren sowie regulative und räumliche Rahmenbedingungen. Der dritte Beitrag thematisiert die operative Eignung des E-Lastenrads, indem seine Fahrtzeiten einem Pkw gegenübergestellt werden. Bei Strecken bis zu 3 km sind beide Modi nahezu gleich schnell. Die Hälfte aller Fahrten bis 20 km Distanz würde bei einem Wechsel vom Pkw zum Lastenrad höchstens 2–10 min länger dauern (ohne Berücksichtigung der Parksuchzeit). Bereits kleine Änderungen an den Verkehrsbedingungen könnten noch bestehende Vorteile des Pkw spürbar verringern. Insgesamt erweitert die Arbeit maßgeblich das Wissen zu einem „neuen alten“ Fahrzeugkonzept, dem ein Potenzial zur Auflösung von bislang auf das Automobil hin ausgerichteten Systemen beigemessen wird. / Shifting trips to electric cargo bikes is one possible solution to deal with the growing challenges of urban commercial transport. This thesis combines conceptual, transport-related, and economic aspects as a foundation to assess the feasibility of this vehicle concept for freight and service trips. It contains five scientific papers, which provide three research contributions. The first contribution identifies the potentials of electric cargo bikes among first users (i.e., courier logistics services). Electric cargo bikes are an updated and re-envisioned version of freight bicycles. The features of point-to-point courier logistics assignments offer a substantial market opportunity for electric cargo bikes. However, being positioned between two established modes (i.e., car and bicycle) handicaps the market entry of cargo bikes. For the second contribution, the scope was widened to include all business sectors. A structured description is presented of the various determinants (i.e., drivers and barriers) affecting commercial cargo bike use. Among these were vehicle-specific factors, structures and practices of the company, attitudes of decision-makers, soft factors, regulatory frameworks, and spatial conditions. The third contribution explores the travel time differences between electric cargo bikes and cars for commercial trips. For trip distances of up to 3 kilometers, the travel times of both modes largely overlap. Half of all trips up to 20 kilometers would take only a maximum of 2 to 10 minutes longer by electric cargo bike (excluding the additional time for finding a parking spot). Small modifications in traffic could have considerable effects in reducing the current travel time advantages of cars. Consequently, this dissertation contributes towards the state-of-research by expanding the scientific knowledge of a type of vehicle that has the potential to disrupt car-dependent transportation systems.

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