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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

Entregas noturnas no município de São Paulo: percepções dos motoristas e recebedores. / Night deliveries in São Paulo: perceptions of drivers and receivers.

Dias, Pedro Augusto Parente 21 October 2016 (has links)
As pesquisas para o desenvolvimento de uma cidade mais sustentável, com menos trânsito e mais qualidade de vida, apontam a necessidade de elaboração de políticas voltadas para o transporte de carga. As entregas urbanas de carga sendo feitas no período noturno pode ajudar a melhorar o trânsito da cidade, e evitar acidentes com ciclistas, pedestres, ônibus e carros. Ao mesmo tempo, entregar mercadorias a noite pode ser vantajoso tanto para os varejistas quanto para os transportadores. Da perspectiva dos varejistas, pode haver mais agilidade em conferir e armazenar mercadorias, melhora do nível de atendimento ao cliente, e mais certeza quanto à pontualidade do horário da chegada do caminhão. Quanto aos transportadores, o tempo de rota pode diminuir, assim como tempo para buscar uma vaga para estacionar; as filas de caminhões podem diminuir, oferecendo mais eficiência ao roteiro de entregas. Entretanto, alguns problemas podem surgir ao executar os descarregamentos noturnos, relacionados à emissão de ruídos e ao risco de assaltos. O objetivo desta pesquisa é assinalar os principais aspectos que influenciam na eficiência das entregas noturnas no âmbito operacional, e identificar quais são os problemas relacionados à execução das entregas noturnas. Para cumprir estes objetivos foi aplicado um questionário a 100 motoristas, e outro questionário a 84 varejistas que realizam operações com entregas/recebimento de mercadorias no período noturno. A partir destes dados, análises estatísticas foram feitas para assinalar quais variáveis de análise estão mais associadas à escolha por executar as atividades de frete no período noturno. Os resultados mostraram que os ruídos são mais críticos para a tomada da decisão do horário de entrega, para os varejistas. Quanto aos resultados atrelados à eficiência logística, a vantagem em fazer entregas noturnas está na maior agilidade para conferir e armazenar as mercadorias e maior assertividade quanto ao horário de entrega, devido às condições do trânsito e da facilidade em estacionar o veículo para efetuar o descarregamento. / The findings of the researches for a more sustainable city, with less traffic and better quality of life, point to the need of new policies for the transport of cargo. Urban overnight deliveries can improve the traffic of city and prevent accidents involving cyclists, pedestrians, buses and cars. At the same time, overnight deliveries might be favorable, both for retailers and drivers. From the perspective of retailers, overnight deliveries may be more efficient in checking and storing goods, more punctual and improve customer service level. For drivers, time route and time to find a place to park may decrease; truck queues may be reduced, which offers more efficiency to the delivery route. However, some problems may arise when performing the night freight, regarding to its noise and the risk of robbery. The objective of this research is to verify the main aspects that maximize the efficiency of night deliveries in the operational context and identify the night freight problems. In order to meet these objectives, a questionnaire was applied to 100 drivers, and another questionnaire to 84 retailers. Statistical methods were used to make sure the noises as the most critical aspects of the night deliveries, for retailers. As for the results related to logistic effectiveness, the advantage of making overnight delivery is the agility to check and store the goods and the accuracy on the delivery schedule, due to traffic conditions, and the ease to park the vehicle to perform the download. In addition, multivariate analysis method combines the quality of customer service with the punctuality of the truck and the agility in check and store goods.
2

Entregas noturnas no município de São Paulo: percepções dos motoristas e recebedores. / Night deliveries in São Paulo: perceptions of drivers and receivers.

Pedro Augusto Parente Dias 21 October 2016 (has links)
As pesquisas para o desenvolvimento de uma cidade mais sustentável, com menos trânsito e mais qualidade de vida, apontam a necessidade de elaboração de políticas voltadas para o transporte de carga. As entregas urbanas de carga sendo feitas no período noturno pode ajudar a melhorar o trânsito da cidade, e evitar acidentes com ciclistas, pedestres, ônibus e carros. Ao mesmo tempo, entregar mercadorias a noite pode ser vantajoso tanto para os varejistas quanto para os transportadores. Da perspectiva dos varejistas, pode haver mais agilidade em conferir e armazenar mercadorias, melhora do nível de atendimento ao cliente, e mais certeza quanto à pontualidade do horário da chegada do caminhão. Quanto aos transportadores, o tempo de rota pode diminuir, assim como tempo para buscar uma vaga para estacionar; as filas de caminhões podem diminuir, oferecendo mais eficiência ao roteiro de entregas. Entretanto, alguns problemas podem surgir ao executar os descarregamentos noturnos, relacionados à emissão de ruídos e ao risco de assaltos. O objetivo desta pesquisa é assinalar os principais aspectos que influenciam na eficiência das entregas noturnas no âmbito operacional, e identificar quais são os problemas relacionados à execução das entregas noturnas. Para cumprir estes objetivos foi aplicado um questionário a 100 motoristas, e outro questionário a 84 varejistas que realizam operações com entregas/recebimento de mercadorias no período noturno. A partir destes dados, análises estatísticas foram feitas para assinalar quais variáveis de análise estão mais associadas à escolha por executar as atividades de frete no período noturno. Os resultados mostraram que os ruídos são mais críticos para a tomada da decisão do horário de entrega, para os varejistas. Quanto aos resultados atrelados à eficiência logística, a vantagem em fazer entregas noturnas está na maior agilidade para conferir e armazenar as mercadorias e maior assertividade quanto ao horário de entrega, devido às condições do trânsito e da facilidade em estacionar o veículo para efetuar o descarregamento. / The findings of the researches for a more sustainable city, with less traffic and better quality of life, point to the need of new policies for the transport of cargo. Urban overnight deliveries can improve the traffic of city and prevent accidents involving cyclists, pedestrians, buses and cars. At the same time, overnight deliveries might be favorable, both for retailers and drivers. From the perspective of retailers, overnight deliveries may be more efficient in checking and storing goods, more punctual and improve customer service level. For drivers, time route and time to find a place to park may decrease; truck queues may be reduced, which offers more efficiency to the delivery route. However, some problems may arise when performing the night freight, regarding to its noise and the risk of robbery. The objective of this research is to verify the main aspects that maximize the efficiency of night deliveries in the operational context and identify the night freight problems. In order to meet these objectives, a questionnaire was applied to 100 drivers, and another questionnaire to 84 retailers. Statistical methods were used to make sure the noises as the most critical aspects of the night deliveries, for retailers. As for the results related to logistic effectiveness, the advantage of making overnight delivery is the agility to check and store the goods and the accuracy on the delivery schedule, due to traffic conditions, and the ease to park the vehicle to perform the download. In addition, multivariate analysis method combines the quality of customer service with the punctuality of the truck and the agility in check and store goods.
3

Aglomerace Olomouc v mezinárodních logistických sítích / Olomouc in international logistic background

Bokij, Lilia January 2009 (has links)
Thesis informs about application of concept city logistics in Olomouc.
4

The Geographic Adaptive Potential of Freight Transportation and Production System in the Context of Fuel and Emission Constraints

Asuncion, Janice Sy January 2014 (has links)
Freight transportation is an integral element of various supply chains and has a complex and dynamical interrelationship with human economic activities. Modern logistical strategies paved way to the current supply chain organisation and logistics network design resulting in a more global economy and huge economies of scale. Recent trends of volatility of oil price have major implications in the movement of commodities across the supply chains. Likewise, climate change issues have presented urgent challenges in reducing carbon emissions for the transport and logistics sector. Pressure on the sector comes from both governments and consumers alike, demanding future sustainability as well as corporate environmental and social responsibility. The original contribution of this research is to investigate the system-wide dynamics of freight transportation and production in the context of supply chains. A theoretical framework called the ‘Geographic Adaptive Potential’ or GAP is built to understand how constraints in energy and emissions affect the production and distribution of commodities. The changes in the supply chain were investigated in four different components, namely a) the potential to shift to less energy and emissions intensive modes for long-haul freight, b) logistical strategies in the last leg of the chain or urban freight and c) local production and distribution, and d) the accessibility of potential customers to the markets. The design of the GAP components is in correspondence with the links of the supply chain. The analyses yielded an evaluation of the adaptive capacity of the freight transport and production system. For long-haul freight, a GIS-based model was created called the ‘New Zealand Intermodal Freight Network’ or NZIFN. It is an optimisation tool integrating the road, rail and shipping network of New Zealand and calculates that minimum time, operating costs, energy and emissions routes between 2 given locations. The case studies of Auckland to Wellington and Auckland to Christchurch distributions of non-perishable products established that even a marginal increase of rail and coastal shipping share produced around 10% reduction in both freight energy and greenhouse gas emissions. In the study of the last leg of the supply chain, the truck trip generation rates of different food stores were investigated. The strongest factors influencing the trip rates to a store are its size and product variation, the latter being a new parameter introduced in the dissertation. It is defined as the total number of brands for 6 chosen commodities commonly found in the stores. The trip rates together with the truck type and distance travelled were used to compute the freight energy usage of the stores. Results revealed that supermarkets consume the most energy for their delivery operations but relative to its physical size, they are more energy efficient than smaller stores. This is due to the utilisation of advanced logistical strategies such as freight consolidation and the effective use of distribution centres. The localised production chapter was explored in the context of Farmers’ markets and their difference with the conventional supermarket distribution system. Using a freight transport energy audit, the energy intensities of both systems were compared. The findings showed that Farmers’ markets were more energy-intensive than supermarkets owing to the low volumes of goods delivered to the market and the lack of freight consolidation effort in the system. The study on the active mode access of potential customers to both Farmers’ markets and supermarkets captured the interplay between freight and personal transport and is the final component of GAP. The results of the ArcGIS based model called ‘Active Mode Access’ or AMA demonstrated that both Farmers’ markets and supermarkets have the same level of accessibility for walking or biking customers. However, the calculations also showed that almost 87% of New Zealanders have no AMA to stores and are at risk for fuel price increase. Finally, the key result of this dissertation is the assessment that there is actually limited adaptive capacity of the freight transport and production system. This is due to network infrastructure and geographical constraints as well as commodity type and mode compatibility and other operational concerns. Due to these limitations, the GAP model assessed that reduction in energy and allowable emissions will ultimately reduce the amount of commodities moved in the system.
5

Participation for Sustainable Urban Freight Transport Systems : A Case Study of Freight Receivers in the City of Gothenburg

Lindkvist, Hannes January 2017 (has links)
This thesis is a case study research that look into the difficulty in engaging freight receivers in initiatives related to urban freight transport. The aim of the paper is to investigate how participatory processes could be formed for more successful outcomes and how the freight receivers could become more engaged in the processes. By conducting a qualitative research where primarily interviews with freight receivers and other concerned stakeholder were made, it was possible to distinguish differences and similarities in views and attitudes toward participation in freight related initiatives. The interviewed freight receivers were located in two different areas in the central business district in the city of Gothenburg, Sweden. In one area, the freight receivers have been included in discussions with the traffic and public transport authority regarding a newly implemented restriction for heavy freight vehicles, and thus have experience with participatory processes. These results show that the freight receivers appreciate the possibility to be a part of the discussion even though they are sceptic towards their possibility to influence on decisions. In the other area, the authority is planning on potentially implement the same restrictions, but as they have not started this process, no stakeholders have yet been included in discussions. Thus, the expectations and attitude towards participation in such a process could be studied among freight receivers in this area. Results in this area show that medium sized business, based on turnover, are more enthusiastic in participating meanwhile smaller business and businesses that are part of a chain store or a franchise are less interested in participating. By comparing the views and opinions between these groups with the interview with the authorities, results show that freight receivers and the traffic and public transport authority in Gothenburg have similar views on the importance of participatory processes, but they differ in their views on what influence the freight receivers have in these processes. By analysing the results with the theoretic concepts of participation, engagement and communication it was possible to identify issues in the case that must be considered in order to establish more rewarding participatory processes. It is concluded that freight receivers must be involved already in the process of defining the problem with urban freight transport to close the gap between how the freight receivers and the authorities experience the participatory process. This would enable finding solutions that considerall interests and thus have higher chance of long-lasting implementation rather that creating conflicts on power relations. Further it is stated that with the help of a combination of a scalon plan, quality circle and representative participation is possible to create an altruistic value in participating which could increase the will to engage in participatory processes and creating more sustainable urban freight transport systems.
6

Opportunities for short-sea shipping in the Southern African Development Community (SADC) region: evidence based on discrete choice modelling

Konstantinus, Abisai 27 February 2020 (has links)
The thesis investigates the development of short-sea shipping (SSS) in the Southern African Development Community (SADC) region by studying the determinants of SSS, the stated choice preference of shippers and freight forwarders and the stated intentions of maritime carriers for SSS. It is purported the introduction of SSS in SADC could reduce socio-environmental problems currently faced such as road damage, road congestion, pollution and transport related accidents. Discrete choice modeling (DCM) is employed as the main methodology to study shipper and carrier behavior. Discrete choice modeling permits the construction of general utility functions incorporating various decision maker characteristics and choice attributes to elicit preference of respondents. The general postulate in DCM is that utility is derived from the properties of things rather than the actual thing per se. A particular benefit of DCM in this study is the elicitation of preference for services and interventions that have not been introduced by SSS. The first step in the study is a theoretical investigation of the potential of SSS in the SADC region. It highlights the policy initiatives, the barriers and enablers related to the development of SSS. The proposed SSS system would have three main roles: to offer an alternative mode of freight transport service between port cities, to serve as the main leg in an intermodal transport network, and to serve feeder services between hub-and-spoke ports. The findings reveal that, SSS has the theoretical potential to work in the SADC region, given the large geographic region, projected freight volumes and customs and trade policies the SADC region is pursuing. The second step in the study involves an a-priori study conducted to develop a general understanding of freight transport in SADC. For this purpose, a uniquely developed online survey was conducted across the SADC region to ascertain in particular: who the decision maker is in terms of freight mode choice; and what the significant attributes that influence freight mode choice are. The results reveal that both the shipper and the freight forwarder are involved in mode choice decisions, however the shipper being the dominant decision maker. Furthermore, the results of the exploded logit model reveal that the top five modal attributes that shippers consider most important are: reliability, transport cost, risk of damage, frequency of service and transit time. These results were subsequently employed to inform the shipper and carrier behavior studies. The third step entails the assessment of shipper behavior, where trip specific mode choice decisions are studied along five intra-urban origin-destination (O-D) paired routes (which would form the study corridors). Three of these corridors considered unimodal SSS, and the two considered intermodal SSS. Unimodal SSS was studied along the following corridors: Cape Town (South Africa)~ Walvis Bay (Namibia), Walvis Bay (Namibia) ~ Luanda (Angola) and Durban (South Africa) ~Beira (Mozambique); and intermodal SSS was studied along the following corridors: Durban (South Africa) ~ Harare (Zimbabwe) and Cape Town (South Africa) ~ Windhoek (Namibia). To develop the choice scenarios, d-efficient stated choice experiments were uniquely developed for each of the corridors with the following key modal attributes systematically varied and analyzed across respondents: service frequency, reliability in terms of arriving on time, expected delay, transport cost and transport time. Subsequently, the following choice models were developed: Binary Logit, Mixed Logit and Integrated Choice and Latent Variable Structure models for the unimodal corridors; and Multinomial Logit, Nested Logit and Cross Nested Logit models for the intermodal corridors. The results highlight that in addition to the modal attributes, mode choice decisions are driven by shipper characteristics and situational characteristics. Moreover, the unimodal SSS study reveals that underlying latent perceptions also influence freight mode choice decisions; while the intermodal SSS study reveal strong correlations in the intermodal SSS alternatives, which requires improved intermodal capability if SSS is to become competitive. The fourth step in the study entail the assessment of maritime carriers preference for SSS given varying levels of maritime conditions that include: dedicated freight volumes, income from freight, port dues discount, terminal handling fees discount and ship registration requirements. The results of an ordered logit model reveal that ship registration provisions and terminal handling charges are the most important to the development of SSS from a carrier side. Moreover, ship registration and maritime cabotage provisions require visitation to boost the participation of carriers in SSS. The last step of the study revisits the modeling results and considers their implications through the estimation of willingness-to-pay and attribute elasticities. The results were then employed to suggest policy actions and interventions to develop SSS.
7

Freight Transport in the Car-Free City : Towards a more sustainable urban freight sector / Godstransporter in den bilfria staden : Mot en mer hållbar godssektor

Marta, Melisa January 2023 (has links)
Freight transport of goods is an indispensable part of everyday life. Without it there would be no delivery of products such as food, water, construction material, technology, furniture, clothes and society, as we know it today, would collapse.  However, there are more and less sustainable ways of transporting goods. Today, the number of freight transport vehicles in cities is increasing steadily which contributes to traffic congestion, unsafety, insecurity, air pollution, noise pollution and climate change. Moreover, as the e-commerce flows are increasing, the importance of sustainable last-mile deliveries increases as well.   The research methods used were literature study and interviews. Firstly, the literature study was realized before two pre-knowledge interviews were conducted. Finally, ten semi structured interviews were conducted with experts, strategists, logisticians,  project managers and consultants.   The data suggests that sustainable urban freight transport can be accomplished with UCCs in combination with cargo bikes to reduce cars in the city. This can be done with the help of four ideas - collaboration, incentives, research and developed bicycle infrastructure.  UCCs are not a new concept but there are few centers that endure due to several factors; flawed business models, lack of expertise or research, subvention dependency and stakeholders’ various engagement and involvement levels. Also, a certain percent of freight that is transported by trucks can be substituted by cargo bicycles but in order to enhance the development of utilizing cargo bicycles as a last-mile delivery option, research and knowledge gap need to be addressed. The conclusion indicates that collaboration between stakeholders, specifically between the private and public sector, is integral. The results also highlight that off-peak deliveries and sustainable last-mile deliveries are feasible solutions. There are knowledge gaps in how UCCs and cargo bikes operate which are potential opportunities for areas of improvement and development. Lastly, policies and regulations set by the local authorities play an integral role to guide the freight industry development towards a more sustainable freight transport. / Godstransport av varor är avgörande i vardagen. Utan fungerande godstransporter skulle det inte finnas leveranser av produkter såsom mat, vatten, byggmaterial, teknik, möbler och kläder, och samhället, som vi är vana vid idag, skulle kollapsa.  Det finns emellertid mer och mindre hållbara sätt att transportera varor på. Idag ökar antalet godstransportfordon i stadskärnor stadigt vilket bidrar till trafikträngsel, osäkerhet, otrygghet, luftföroreningar, buller och klimatförändringar. Dessutom ökar e-handelns flöde i rask fart vilket leder till att betydelsen av hållbara last-mile leveranser ökar likaså. Forskningsmetoderna som användes var en litteraturstudie och intervjuer. Först genomfördes litteraturstudien, följt av två intervjuer för att få en förståelse och en gedigen bakgrund i ämnet. Slutligen genomfördes tio semistrukturerade intervjuer med experter, strateger, logistiker, projektledare och konsulter för att få en fördjupad kunskap om bl.a. problem och utvecklingsmöjligheter inom ämnesområdet.  Resultaten antyder att godstransporter kan utföras med hjälp av samlastningscentraler (UCC) i kombination med lastcyklar för att minska antalet bilar i staden. Effektiva samlastningscentraler ställer krav på väl utvecklat samarbete, incitament, forskning och cykelinfrastruktur. UCC är inget nytt koncept, men det finns få center som överlever på grund av flera faktorer: bristfälliga affärsmodeller, brist på expertis eller forskning, subventionsberoende samt olika nivåer av engagemang och deltagande från intressenter. En viss andel av godstransporterna som utförs med lastbilar kan ersättas av lastcyklar. För att främja utvecklingen av användningen av lastcyklar som last-mile lösning krävs dock forskning och ökad kunskap.  Slutsatsen pekar på att samarbete mellan intressenter, särskilt mellan privata och offentliga sektorer, är avgörande. Resultaten belyser också att off-peak leveranser lågtrafikperioder och hållbara last-mile lösningar är genomförbara alternativ. Det finns kunskapsluckor när det gäller drift av UCC och lastcyklar, vilket kan ses som en möjlighet till förbättring och utveckling. Slutligen spelar lokala myndigheters policys och regler en viktig roll för att styra godstransportindustrins utveckling mot en mer hållbar transport av gods.
8

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.
9

Modélisation dynamique du trafic et transport de marchandises en ville : vers une approche combinée / Dynamic traffic modeling and urban freight : a combined approach

Lopez, Clélia 01 December 2017 (has links)
Cette thèse propose une modélisation des interactions entre le Transport de Marchandises en Ville (TMV) et la dynamique du trafic. Ces deux composantes, pourtant imbriquées, ne sont que très rarement étudiées simultanément. Plus précisément, cette thèse investigue les impacts du TMV sur les états de trafic ; et inversement, les impacts des états de trafic sur le TMV. Les recherches s’articulent autour de deux axes : le TMV à l’échelle (i) de la livraison et (ii) de la tournée de livraison, et la dynamique du trafic à l’échelle (iii) d’un jour et (iv) d’un catalogue de jours. (i) Le TMV réalisé par des véhicules routiers peut engendrer des formes de congestion, et par conséquent des nuisances sonores et atmosphériques. Néanmoins, il s’agit d’un « mal nécessaire » car le transport de ces marchandises est essentiel pour l’économie des villes. Une pratique courante est la livraison en double file. Ces « stationnements sauvages » réduisent l’écoulement des véhicules dans le réseau de transport. Une étude de sensibilité quantitative en simulation microscopique met en lumière une dégradation significative des états de trafic sur un boulevard urbain à partir d’un faible nombre de stationnements en double file. Ces phénomènes locaux et temporaires semblent essentiels à intégrer dans les simulations du trafic afin d’étudier au mieux les performances globales du système de transport. (ii) Les tournées de livraison planifiées peuvent être améliorées par l’intégration des conditions de circulation. Les algorithmes existants d’optimisation de tournées se basent sur une certaine qualité et quantité de données. Nous investiguons l’influence de plusieurs niveaux de granularité d’information du trafic sur l’ordonnancement optimale des tournées. De plus, nous comparons les temps de parcours estimés par les algorithmes, et les temps de parcours effectifs estimés à l’aide d’une simulation microscopique. Les états de trafic attendus peuvent être sujets à quelques variations. Nous proposons une méthodologie de génération de tournées intégrant de l’incertitude dans la dynamique du trafic. (iii) À l’échelle de la ville, les états de trafic sont naturellement variables, que ce soit dans l’espace ou au cours du temps. Le partitionnement permet de découper un réseau de transport en zones homogènes. Une zone est définie par un ensemble de liens connectés ayant des conditions de circulation similaires. Nous proposons une approche spatio-temporelle définissant des zones en 3 Dimensions (3D). L’idée est de résumer la majeure partie de la dynamique du trafic d’une ville en utilisant peu d’information : la vitesse moyenne par zone spatio-temporelle. Deux familles de méthodes de clustering fondamentalement différentes sont comparées et évaluées. Le cas d’étude est le réseau d’Amsterdam avec des données réelles. (iv) D’un jour à l’autre, la dynamique du trafic peut être similaire. Nous proposons une méthodologie regroupant les jours par leurs motifs de congestion. L’existence d’une régularité dans les motifs journaliers est introduite par la notion de jour-type. Un jour-type est le jour de référence d’un groupe de jours. Nous validons notre modèle en comparant les temps de parcours effectifs et les temps de parcours estimés par les jours-types. Diverses applications peuvent être raffinées à partir de quelques jours-types, comme l’assistance routière et la génération de tournées. / This thesis aims to modeling the interactions between the urban freight and the traffic dynamic. Although both are intertwined, they have rarely been studied considering a combined approach. Specifically, the main purpose is to analyze the impacts of the urban freight on traffic states, and vice versa. This research is focused on two axes: the urban freight considering (i) the delivery and (ii) the delivery route scales, and two traffic dynamic scales describing (iii) a day and (iv) a set of days. (i) The delivery of goods carried by vehicles can produce traffic congestion, noise and air pollution. Nevertheless, the transport of goods is essential for the economy of cities. The double parking is a common way for delivery trucks. This illegal parking reduces the vehicle capacity of the transportation network. A sensitivity analysis in traffic microscopic simulation model for urban freight highlight a significant decreasing of the traffic conditions on an urban corridor considering a low number of double parking. These local and temporal phenomena are essential to be integrated into the traffic simulation in order to better study the overall performance of the transportation system. (ii) The delivery route planner can be improved by integrating traffic conditions. The route optimization algorithms are based on quality and quantity of given data available. We investigate the influence of several levels of granularity on traffic information data for the optimal route scheduling. Moreover, the travel time estimated by algorithms and the effective travel time estimated by a microscopic simulation are compared. In addition, the expected traffic conditions can be subject to variations. We propose a methodology of delivery route planner integrating the uncertainty of the traffic dynamics. (iii) At the city level, the traffic conditions are varied through space and time. A partitioning of urban transportation networks makes possible to identify homogeneous zones. A zone is defined by a set of connected links with similar traffic conditions. We proposed a spatial and temporal approach to define the 3D zones. The idea is to summarize the majority of the traffic dynamics of a given city using only a few information: the mean speed per spatial and temporal zone. Two fundamentally different methods of clustering are compared and evaluated. The study case is the Amsterdam network with its real-world traffic data. (iv) From day to day, the traffic dynamic can be similar. We proposed a methodology grouping days by their similar congestion patterns. The existence of a regularity through daily patterns are introduced by consensual speed map. A consensual speed map is the reference day representing a group of days. Our model is validated by using the effective travel time and estimated ones by the consensual speed maps. Numerous applications can be refined from a couple of consensual speed maps, as the route guidance and delivery route planning.
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A utilização de dados de GPS de rastreamento de veí­culos para extrair indicadores operacionais do transporte urbano de cargas: estudo de caso no Brasil. / The use of GPS tracking data to extract logistics performance indicators of urban freight: case study in Brazil.

Andrade, Patricia Faias Laranjeiro de 20 March 2019 (has links)
Esta pesquisa propõe uma abordagem genérica de processamento de dados de rastreamento de veículos de carga com a finalidade de extrair indicadores de desempenho logístico no contexto urbano. Tais indicadores são importantes para caracterizar como as operações logísticas se desenvolvem nas cidades e subsidiar o processo de tomada de decisão dentro do âmbito do planejamento urbano de cargas, por parte do poder público. Esta abordagem é aplicada a três bases de dados - para a Região Metropolitana de São Paulo (RMSP) - obtidas junto a empresas privadas distintas, sendo duas grandes redes varejistas e a terceira uma provedora de serviços de mapas. Apesar de algumas limitações nos dados disponíveis, foi possível identificar paradas dos caminhões e analisar suas características, como: distribuição espacial e temporal, frequência de paradas por veículo, a localização de clusters de paradas etc. Além disso, foi possível classificar do os veículos que circulam na cidade distinguindo a parcela que corresponde ao \'fluxo de passagem\", veículos que estão apenas cruzando a cidade (São Paulo) e, por fim, apresentou-se também um estudo do perfil de velocidades - por hora e dia da semana - em uma importante via arterial de São Paulo. Os resultados e análises desta pesquisa reforçam que há grande potencial na utilização de dados de rastreamento de veículos de carga no contexto do planejamento de transporte urbano de cargas, embora este dependa em parte de algumas especificidades dos dados, como a frequência dos registros, a precisão da posição geográfica coletada, além da necessidade de um processamento otimizado devido ao grande volume de dados. / The purpose of this research is a general approach for processing tracking data of cargo vehicles in order to extract logistic performance indicators in the urban scenario, essential to characterize how logistic operations are developed and support the decision-making process within the scope of urban freight planning by the public sector. This approach is applied to three data bases - for the São Paulo Metropolitan Region (SPMR) - acquired from different private companies, being two large retailers and the third a great mapping services provider. In spite of available data limitations, it was possible to identity truck stops and analyze its particulars, such as: spatial and temporal distribution, stop frequency per vehicle, the location of stop clusters, etc. Apart from that, it was possible to classify among the flow of vehicles in the city, the ones that are just passing, crossing the city, and ultimately, it was presented a speed profile analysis - per day and week day - of an important arterial way of São Paulo. The results and analysis of this research reinforce that there is great potential in the use of cargo vehicle tracking data for urban freight planning, even though it partially depends on some data specifics, such as frequency of records, location accuracy, besides the need of an optimized data processing due to their great volume.

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