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This thesis aims to optimize the transportation of goods in a logistics network including a set of shippers and retail facilities. Specifically, we study the problem of shippers who purchase transportation services from different carriers offering FTL or LTL rates. In a first part, we solve a vehicle routing problem with a single depot and heterogeneous fleets offered by several carriers. An original feature of the problem is a constraint limiting the total number of vehicles offered by each carrier. We solve this problem with a Large Neighborhood Search metaheuristic including a filtering algorithm arising from constraint programming. In a second part, we study a pickup and delivery problem with the possible use of intermediate platforms. The distribution from these platforms is ensured by regional carriers. This problem is formulated as a pickup and delivery problem with options that we solve with a metaheuristic alternating small and large destructions. We conclude this thesis with several case studies conducted within the CRC Services company.; Cette thèse a pour but d'optimiser le transport de marchandises dans un réseau logistique incluant des chargeurs et un ensemble d'entrepôts ou points de vente de la grande distribution. Nous étudions en particulier la problématique des chargeurs qui achètent des services de transport à différents prestataires logistiques proposant des tarifs FTL ou LTL. Dans une première partie, nous résolvons un problème de tournées de véhicules depuis un dépôt unique avec des flottes hétérogènes proposées par plusieurs transporteurs. Une caractéristique originale du problème est la formulation d'une contrainte d'engagement maximum des transporteurs en terme de nombre de véhicules. Nous résolvons ce problème avec une métaheuristique de type Recherche à Voisinage Large intégrant un algorithme de filtrage issu de la programmation par contraintes. Dans une seconde partie, nous étudions un problème de collectes et de livraisons avec la possibilité de livrer les marchandises sur des plateformes intermédiaires. Des transporteurs régionaux assurent alors la distribution en aval de ces plateformes. Nous formulons ce problème comme un problème de collectes et livraisons avec options et proposons une métaheuristique alternant des destructions de petite et de grande taille. Nous concluons cette thèse par plusieurs cas d'étude menés au sein de la société CRC Services.

Während der Transportsektor in der EU aufgrund steigenden Bedarfs ständig wächst, ist er für einen großen Teil des Energie- und CO2-Verbrauchs verantwortlich. Im Güterzugverkehr, eine der klimafreundlichsten und preisgünstigsten Optionen, werden meist zwei verschiedene Zugverkehrstypen eingesetzt: Der flexiblere Wagenladungsverkehr und der günstigere Ganzzugverkehr.In dieser Arbeit untersuchen wir einen alternativen Ansatz aus Sicht einer Spedition, der die Vorteile beider Zugverkehrstypen kombiniert. Im "Multiple Collaborative Round Trip Problem" (MCRP) optimieren wir den Transport von 20' Standardcontainern und den Einsatz von Ganzzügen, die ähnlich wie Passagierzüge fahren: Sie haben fixe Fahrplänen, wiederholte Fahrten - sogenannte ``Round Trips'' - und mehrfache Stops. Leerfahrten oder schlecht ausgelastete Zugfahrten werden vermieden, indem die geladenen Container auf andere Züge (oder Fahrten) verlagert werden und dadurch gesamte Fahrten weglassen und eingespart werden können.Wir stellen eine formale Problembeschreibung auf, repräsentieren das Problem mit Hilfe eines ``Time-expanded Networks'', lösen es exakt durch die Modellierung eines ``Integer Linear Programs'', und beweisen die Komplexität des MCRP. Wir generieren künstliche Instanzen, um die Performance unseres Ansatzes und die Eigenschaften der Lösungen zu den Instanzen zu untersuchen. Diese beruhen auf einem echten Schienennetzwerk und fundierten Werten aus Literatur und Feedback unseren Projektpartner:innen.Wir untersuchen unseren Algorithmus auf Laufzeit und andere Qualitätskriterien, den Einfluss von Instanz-Parametern auf die Komplexität des Problems und dessen Lösungseigenschaften, und eine einzelne beispielhafte Lösung, um tieferen Einblick in die Lösungsstrukturen unserer Instanzen zu erhalten. Außerdem vergleichen wir die künstlichen Instanzen mit der derzeitigen Praxis und untersuchen die Anwendbarkeit unseres Ansatzes in der Praxis., In times of globalization and climate change, the freight transportation sector faces increasing demand. At the same time, it is responsible for a major part of the energy consumption and CO2 emissions in the European Union. Rail freight transport appears to be one of the best choices when considering economical and ecological aspects.In current practice, two types of rail freight are common: In so-called "wagonload freight", individual trains are composed of individual wagons, while "block trains" have a fixed set of wagons and directly connect their source to their destination without intermediate stops.Wagon load trains allow more flexibility, but the uncoupling and rearranging operations of wagons are rather costly. In this study, we investigate an alternative approach to combine the advantages of both operation techniques and potentially increase the efficiency of the freight sector.We optimize the shipment of individual 20' containers, which are carried by block trains. These block trains operate on fixed schedules with potentially recurring round trips and multiple stops, similar to passenger trains. The idea is to avoid empty runs and underutilized round trips by shifting the respective containers to other trains or round trips. These empty round trips then do not have to take place, hence costs are saved.The corresponding problem is called "Multiple Collaborative Round Trip Problem"(MCRP). It arises in the context of the research project PhysICAL from the point of view of a freight forwarder in collaborative logistics. If the container paths are optimized from a global point of view, the operational cost of the freight forwarder can be reduced. In return, the operator can then offer better prices to its customers.We formally define the MCRP and represent it with the use of a time-expanded network, state an Integer Linear Program (ILP) to solve it in an exact way, and prove the NP-completeness of its decision variant.To investigate and benchmark the problem, we generate a set of artificial instances. They are based on a real-world rail network and connect a subset of ten relevant cities for current rail freight transport in Europe. The individual instance parameters and values are researched or provided by our project partners.We analyze the performance of our algorithm, the hardness of the problem, and the characteristics of the solutions for a variety of instance parameters. We also investigate a single solution in detail to provide deeper insights into the composition of the solutions. At last, we compare our method to the state of the art and draw managerial insight from our results.

Research background: Individual car transport significantly burdens the environment, especially in the centres of large cities. There is pollution, traffic jams and an increase in overall noise. In the area of passenger car transport, legislation is being significantly tightened. Therefore, there are also increasing demands on public transport operators in the Czech Republic. Previously, most of the fleet consisted of diesel vehicles. These have been gradually replaced by drives that are significantly more environmentally friendly, such as the Compressed natural gas drive. The requirements defined in relation to the reduction of vehicle emissions are increasingly stricter. A number of cities, not only within the European Union, are addressing significant issues concerning the future of public transport. Purpose of the article: The main objective of the article is to demonstrate an in-depth analysis of the operation of transport vehicles in the Statutory City of Ostrava, both from the cost and environmental point of view. The comparison of transport means using CNG, electric and diesel propulsion is made. Specific factors such as the route profile or the environmental impact of the mode of transport are also taken into account. The extent of the data processed and the multidimensional nature of the assessment offer a unique analysis of the problem. The article provides an exact view of the advantages and disadvantages of operating specific means of transport. Everything is based on data on transport operations in the city of Ostrava (the Czech Republic, EU). Methods: The comprehensive evaluation is based on the application of methods from the field of financial accounting, evaluation of measured data from the operation of transport means and, last but not least, on the analysis of empirical data from the given area. The analysed data set is unique due to the time period, as is the multi-criteria evaluation methodology. Findings & value added: The analysis performed demonstrated the economic viability of operating CNG vehicles. The main added value of the article is the unique multi-criteria evaluation procedure for the vehicles. The paper shows the evaluation of a complex decision problem in the transport field in the form of a case study implemented in the city of Ostrava. The evaluation results then consider both cost and environmental factors, which can be described as a comprehensive and highly innovative approach. The defined assessment can then be applied to other European and world metropolises.

Intermodalni transport počinje se u komercijalne svrhe koristiti od 1960. godine. Jedan od glavnih uzroka razvoja tog sustava bila je potreba za uklanjanjem nedostataka željezničkog prometa poput nemogućnosti otpreme od „vrata do vrata“, spajanje prednosti različitih modova prijevoza u svrhu optimizacije transporta, zaštita okoliša, rasterećenje cestovnih prometnica i smanjenje eksternih troškova koji su posljedica transportnih djelatnosti. U ovom završnom radu obrađeni su elementi, procesi i subjekti u intermodalnom sustavu, definirana je terminologija intermodalnosti te njen značaj za gospodarstvo. Cilj rada je dati uvid u najrazvijenije suvremene tehnologije u intermodalnom transportu, njihov princip rada, sredstva za rad i ciljeve pojedinog sustava, te prednosti i nedostatke. Također, u radu je izrađena analiza značajki intermodalnih transportnih tehnologija (dostupnost, brzina, trošak..) te je na temelju toga dan prijedlog korištenja pojedinih tehnologija na području Republike Hrvatske. Intermodal transport has been used for commercial purposes since 1960. Some of the main reasons for the development of such system was the need to eliminate the shortcomings of rail transport such as the inability to deliver “door to door”, combining the advantages of different modes of transport to optimize transport process, environmental protection, relieving roads and reducing external costs resulting from transport activities etc. In this undergraduate thesis, the elements, processes and subjects in the intermodal system are shown. Furthermore, the terminology of intermodality and its significance for the economy are defined. The aim of this undergraduate thesis is to provide insight into the most developed modern technologies in intermodal transport, their working principle, means of operation and goals of each system, as well as advantages and disadvantages. Also, the thesis analyzes the characteristics of intermodal transport technologies (availability, speed, cost...) and based on that, a proposal for the use of certain technologies in the Republic of Croatia is given.

The aim of the presented research was to characterize the driving related to the deliveries of large−size Scots pine wood and to determine the factors affecting its structure and distance. Operation was divided in to: driving for load on a public and forest road, forest ride between loading points, as well as driving with saw logs on a forest and public road. Data on the distance traveled on forest and public roads (empty and with load), as well as, the number of loading places was determined on the data from drivers. In total, 1509 randomly selected deliveries carried out over a period of twelve months from 40 forest districts were analyzed. Investigated transports delivered 44,336 m of large−size pine round wood to the sawmill. Most deliveries were made within 100 km from the plant. Within this radius, 83.87% of drives for load and 75.35% drives with load were completed. The average distance for driving for load on a public road was 60.6 km, with the range from 0.5 to 205 km. The average driving distance with load to the sawmill was 70 km, the shortest distance 2 km and the longest – 238 km. Driving distances on forest roads, for and with load, was on the similar level of 3.5 and 3.4 km, respectively. The average distance in the forest, between loading points was 3.1 km, with SD=2.9 km, maximum 16 km. The largest share, 51.4% of total delivery distance, was related to driving with saw logs on a public road and depends on how many places in the forest the wood was picked up. In 36% of all deliveries, saw logs were loaded from two or more places, which involved additional drive on forest roads at the distance of 1,652 km. The analysis did not show statistically significant differences between driving depending on the season of the year. The stable wood supply during 12 months period, shows that large stocks of round wood to secure productions during sensitive periods (winter), is not needed., Sylwan 164 (8): 651-662

The modifiable areal unit problem is of great importance in geographic science. The use of a specific zoning impacts the social and economic imbalances that can be generated in the deployment of services, facilities, and infrastructure. In this article, GIS is used together with simulation and optimization tools to analyse the effects of bus frequency changes in the levels of service and horizontal equity derived from different types of territorial zoning. The city of Palma (Balearic Islands, Spain) was chosen as a case study for the method, for which different geographical areas are used: neighbourhoods, census sections, cadastral blocks, and a 400 × 400 m mesh. The results show significant variations of the optimal frequencies obtained, depending on the type of zoning used. In general, smaller zonings show much higher sensitivity for the detection of imbalances between the population and bus service level. Likewise, orthogonal zonings also prove useful for identifying service and population concentration over other zonings. The use of large spatial units could lead to the misdiagnosis of needs and the implementation of actions that do not actually improve the level of service or the equity of the transport service. It is recommended to consider combining zonings of different sizes simultaneously, in order to accurately highlight imbalances and to argue for transport service improvements.

Smart mobility and transportation, in general, are significant elements of smart cities, which account for more than 25% of the total energy consumption related to smart cities. Smart transportation has seven essential sections: leisure, private, public, business, freight, product distribution, and special transport. From the management point of view, transportation can be classified as passive or non-cooperating, semi-active or simple cooperating, active or cooperating, contract-based, and priority transportation. This approach can be applied to public transport and even to passengers of public transport. The transportation system can be widely observed, analyzed, and managed using an extensive distribution network of sensors and actuators integrated into an Internet of Things (IoT) system. The paper briefly discusses the benefits that the IoT can offer for smart city transportation management. It deals with the use of a hierarchical approach to total transportation management, namely, defines the concept, methodology, and required sub-model developments, which describes the total system optimization problems, gives the possible system and methodology of the total transportation management, and demonstrates the required sub-model developments by examples of car-following models, formation motion, obstacle avoidances, and the total management system implementation. It also introduces a preliminary evaluation of the proposed concept relative to the existing systems.

The population density in European cities and the increasing of car flows are the main reason of bottlenecks, congestions in cities and disaggregation of quality of life in these cities. Road transportation is not the best way for respecting environmental improvements. Cities like Paris, take political decisions for decreasing this high level of road transportation and changing gasoil consumption. Economic advantages for alternative to road transportation have to be shown to companies in order to accelerate their switching decision. This paper focuses on the optimization of restaurant waste management by using fluvial transportation. The idea is to adapt complex systems modeling to this case and show how this activity sector companies could be competitive. Formalisms and tools of GRAI methodology has been used for elaborating appropriated concepts to this sector optimization. An example integrating real data (with a simulation by using Anylogic tool) will be presented for illustrating theoretical propositions.

In this paper, a criterion for predicting the reliability of freeway traffic flow is presented. The idea is based on an analysis of spot speed time series divided into sequences of events of random and homogeneous traffic processes. For each process, the flow rate and density were calculated; then the relationships between parameters of spot speed processes and vehicular density were obtained. Using these relationships and a simulation procedure for the spot speed process, a formulation for predicting the reliability of traffic flow moving along the offside lane on the freeway roadway was derived. Through this formulation and the measurements of flow rate and speed, the probability of instability of the roadway under examination was calculated. Furthermore, with an inverse procedure, the capacity of a lane was estimated: setting the reliability value close to 1 and considering a 15 min interval, the resulting flow rate represented the capacity. Thus, the simulation procedure was used to provide, in real time, the incoming instability conditions on the roadway and to estimate roadway capacity for the A22 Brenner Freeway, Italy.

Transmission system operators need to adapt their decision-making tools to the technological evolutions of the twenty first century. A computation inherent to most tools seeks to find alternating-current power flows that minimize power loss or generation cost. Mathematically, it consists in an optimization problem that can be described using only addition and multiplication of complex numbers. The objective of this thesis is to find global solutions, in other words the best solutions to the problem. One of the outcomes of this highly collaborative doctoral project is to use recent results from algebraic geometry to compute globally optimal power flows in the European high-voltage transmission network.; Les gestionnaires des réseaux de transport d'électricité doivent adapter leurs outils d'aide à la décision aux avancées technologiques du XXIième siècle. Une opération sous-jacente à beaucoup d'outils est de calculer les flux en actif/réactif qui minimisent les pertes ou les coûts de production. Mathématiquement, il s'agit d'un problème d'optimisation qui peut être décrit en utilisant seulement l'addition et la multiplication de nombres complexes. L'objectif de cette thèse est de trouver des solutions globales. Un des aboutissements de ce projet doctoral hautement collaboratif est d'utiliser des résultats récents en géométrie algébrique pour calculer des flux optimaux dans le réseau Européen à haute tension.

Transmission system operators need to adapt their decision-making tools to the technological evolutions of the twenty first century. A computation inherent to most tools seeks to find alternating-current power flows that minimize power loss or generation cost. Mathematically, it consists in an optimization problem that can be described using only addition and multiplication of complex numbers. The objective of this thesis is to find global solutions, in other words the best solutions to the problem. One of the outcomes of this highly collaborative doctoral project is to use recent results from algebraic geometry to compute globally optimal power flows in the European high-voltage transmission network.; Les gestionnaires des réseaux de transport d'électricité doivent adapter leurs outils d'aide à la décision aux avancées technologiques du XXIième siècle. Une opération sous-jacente à beaucoup d'outils est de calculer les flux en actif/réactif qui minimisent les pertes ou les coûts de production. Mathématiquement, il s'agit d'un problème d'optimisation qui peut être décrit en utilisant seulement l'addition et la multiplication de nombres complexes. L'objectif de cette thèse est de trouver des solutions globales. Un des aboutissements de ce projet doctoral hautement collaboratif est d'utiliser des résultats récents en géométrie algébrique pour calculer des flux optimaux dans le réseau Européen à haute tension.

This thesis focuses on the optimal design of one-way station-based carsharing systems. We consider the system design through two structural aspects: the optimal system dimensioning (number of parking places, vehicles, battery capacities, etc.) and the identification of appropriate stations’ locations. Although the addressed problems do not directly concern the system management, some relevant aspects (like vehicle relocation operations) are nonetheless part of the models. The modelling approach uses graph theory to represent the system dynamics over time and various optimization models (ILPs and MILPs) are proposed. The objective is to deduce an optimal shape of the whole system (number of vehicles, parking places, jockeys, stations’ locations, etc.) allowing to capture the maximum number of estimated time-dependent requests. Electric vehicles and power supply are also included in an enhanced model version and context related constraints ensure the integrity of the whole model. The optimization allows to study the impact of different power supply technologies and settle the minimal autonomy a shared vehicle necessitate in this environment. Models are applied to realistic case studies, using both random generated data and real estimated outputs of simulation tools. Strategies including vehicle relocation operations managed by jockeys (employees of the carsharing operator) are considered. We propose some graph simplifications reducing the problem size and leading to greatly improve solver capabilities as well as computation times. A greedy heuristic helping to quickly find feasible solutions and initialize the solver is also proposed and illustrated., Cette thèse s'intéresse à la conception optimale d'un système d'autopartage de type one-way avec stations. Les problèmes abordés traitent de deux aspects structurels importants : le dimensionnement optimal du système (nombre de places de parking, de véhicules, de relocalisation de véhicules, etc.) et la localisation adéquate des stations. Bien que le management ou pilotage en temps réel du service ne soit pas l'objet de cette étude, certains aspects pertinents (relocalisation de véhicules, nombre de jockeys) ont toutefois été intégrés aux modèles. L'approche mathématique utilise des objets de la théorie des graphes pour représenter les systèmes dans le temps et les problèmes sont résolus grâce à la programmation linéaire en nombre entiers. L'objectif est d'identifier la structure du service permettant de capturer le plus de demandes possibles. L'introduction de véhicules électriques et de la puissance de charge en station sont étudiés dans un modèle dédié. Les expérimentations s'appuient sur des données réalistes, générées aléatoirement. Nous nous intéressons particulièrement aux pistes d'amélioration des temps de calculs et de réduction des graphes. Une heuristique gloutonne permettant d'identifier rapidement une solution réalisable est en particulier proposée. Enfin, une étude de dimensionnement des batteries confirme que des capacités deux fois inférieures à celles actuellement sur le marché sont viable dans le contexte urbain actuel.

International audience; Carsharing is today considered as an ecological and innovative solution to improve urban mobility. The one-way version, where vehicles can be drop-off in any station, brings however some challenging open questions. The system has to be design as part of the global transportation one and vehicle relocation operations must be included to get the higher level of service. In this paper, we consider a one-way carsharing system where stations and their location are fixed. The optimization problem consists in maximizing the total number of satisfied demands for a limited number of vehicles and relocation operations. We propose a formal definition and a mathematical model using Integer Linear Programming (ILP). We show that the problem size is strongly related to the number of possible relocation operations and a polynomial subcase is exhibited. Numerical results highlight that vehicle relocations can be drastically reduced without deteriorating the quality of solutions. Our method can thus be easily used in system management to evaluate possible implementation of vehicle relocation strategies.

Colloque avec actes et comité de lecture. internationale.; International audience; "Carsharing systems have gathered increasing attention and are now recognised as innovative and ecological solutions to transportation issues. Especially, one-way carsharing systems offer a high level of service because they exempt users from the obligation to return the vehicle at the same station where it was borrowed. Unfortunately, this flexibility comes with design complexity. This paper addresses a part of those design issues and deals with fleet dimensioning including vehicle relocation operations.We propose mathematical programming oriented approach and we introduce a simple linear model based on integer flow variables. This model is organized around three optimization criteria: maximizing satisfied carsharing demands while minimizing the fleet of vehicles and the relocation operations. From random generated benchmarks, we study the scalability of our method and we show that computation times remain acceptable for representative problem complexities."

Javno podjetje Komunala Laško, d. o. o., opravlja pomembne gospodarske panoge na področju Občine Laško, kar omogoča visok standard bivanja v kraju ob Savinji. Ne glede na recesijo in posledično zmanjševanje finančnih virov je potrebno opravljati komunalne storitve na dosedanji ravni. S pomočjo tehnologije in organizacijskih sprememb je mogoče doseči primerljiv učinek z enakim številom tehničnih sredstev ob zmanjšanem proračunu Občine Laško. V diplomskem delu je predstavljeno obstoječe stanje pri JP Komunala Laško, d. o. o., na področju odvoza odpadkov ter optimizirano stanje na podlagi opravljene analize. Cilj diplomskega dela je prikazati tehnologije, potrebne za odvoz odpadkov, organiziranje odvoza mešanih komunalnih odpadkov ter opravljeno optimizacijo, narejeno s pomočjo napredne tehnologije, ki nam omogoča nadzor voznega parka in zaposlenega kadra. Namen je ohraniti enako oz. izboljšano raven poslovanja z zmanjšanimi finančnimi sredstvi. Public company Komunala Lasko, d. o. o., carries significant industries in the municipality Lasko allowing high standard of living in the area near Savinja. Regardless of the recession and the consequent reduction of financial resources necessary to carry out municipal services to current levels. With the help of technology and organizational changes it is possible to achieve the same effect with the same number of technical assets at a reduced budget of the municipality Lasko. The thesis presents the current state of JP Komunala Lasko, d. o. o., in the field of waste disposal and optimized state on the basis of the analysis carried out. The aim of the thesis is to demonstrate technologies needed for waste removal, organisation of removing mixed municipal waste, optimization, carried out using advanced technology, which allows us to control the vehicle fleet and employee staff. All in order to maintain the same or improved level of operating with reduced funding.

MATSim is a large-scale multi-agent, activity-based transport simulation model. It can simulate each person in a urban area, managing millions of agents in reasonable computation times. Besides supply information, MATSim needs a planned activity schedule for every person as input data. Its time horizon is one day, and the activity-trip chains have to be fully defined before each simulation (start-time, duration, location, trip mode, and sequence for the entire day). MATSim scores the simulation, mutates agents' plans and executes a new simulation many times, optimizing the macroscopic indicators and reaching user equilibrium conditions. However, the one day time horizon is a hard restriction for studying current transport planning challenges using MATSim. Recent studies show that the behavioral variety of travelers can not be well analyzed with only one day simulation results. Usual analysis procedures, like clustering the population according to their travel behavior, need multi-day information to account for intra-personal variability. Furthermore, longer time horizons allow to include restrictions like time and money budgets, and to simulate individual mode choice over time, identifying mode clienteles. Developments of advanced time consumption travel models require observations of at least a week for calibration purposes, because a complete cycle of work and leisure must be included. In conclusion, time consumption decisions that humans take inside a day depend on individual and collective behaviors. These behaviors only can be simulated and analyzed with longer term models. Understanding the importance and pertinence of simulating transport with a multi-day time horizon, this paper discusses how MATSim can be expanded to execute one week time activity plans. The discussion is conceptual because no full implementation has been developed yet. The paper emphasizes two key aspects of the expansion: optimization strategies, and the generation of weekly plans. For each aspect alternatives are proposed, analyzed and compared. The impact of the proposed development on each step of the simulation process is taken into account. The problem of scheduling and re-scheduling and its relation to computational time in large-scale scenarios has to be kept in mind for weekly plans even more so than for daily plans. Activity plan generation procedures ranging from simpler, but faster methods to advanced ones, involving econometric approaches or complex mental processes, are compared. Concepts like fixed and floating activities, activity agendas or shared activities (within households or with social networks) have to be evaluated for their impact. Furthermore, several options for performing the optimization of plans are presented, highlighting their advantages and disadvantages (e.g. full-week re-planning or end-of-day re-planning). Computing time and memory consumption are taken into account according to previous measures and expected indicators. It is easy to realize that the mobility simulation (traffic flow) module does not need significant changes when the total time is modified. However, if a within-week re-planning strategy is implemented modifications in this module and its implications are explained and evaluated as well. The paper concludes with a proposed methodology for developing this MATSim extension, Arbeitsberichte Verkehrs- und Raumplanung, 822