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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Evaluating the Performance of the Freight Transportation System of the Great Lakes Region: An Intermodal Approach to Routing and Forecasting

Wang, Qifeng January 2014 (has links)
No description available.
52

Survivability enhancement in a combat environment

Seow, Yoke Wei. 12 1900 (has links)
Approved for public release, distribution is unlimited / The objective of this thesis is to provide an aircraft with an optimal route to its destination that avoids encroaching into surface-to-air weapons killing envelopes in real time. The optimal route computed will be updated dynamically, depending on the location of the vehicle and the location of the Surface to Air Missile (SAM) sites. The problem was solved using heuristic algorithms instead of the conventional Dijkstra's & Bellman Ford algorithms, which are computationally expensive. Data fusion techniques such as spatial correlation and triangulation algorithms are presented in detail. Such techniques are important for situational awareness in a real time combat environment. Important information provided by onboard sensors are merged with the preplanned data to provide the operator with a better integrated picture of the combat environment. / Civilian, Singapore Ministry of Defense
53

Ruttplanering : Retursystem för pantade PET-flaskor och aluminiumburkar / Route planning : Recycle system for deposit bottles and aluminium cans

Nilsson, Carl, Johansson, Sofie January 2008 (has links)
This report is the final part within our education, Industrial Organization and Economy focusing on Logistics and Management at Jönköping School of Engineering. The aim with this report is to coordinate recycle drives for deposited aluminum-cans and bottles collected from grocery stores within Jönköping county and locality. In the present situation both aluminum cans and bottles filled with drinks are distributed to the grocery stores by the brewery’s own distributers. At the same time as they supply the drinks they also discharge the grocery stores units with restored aluminumcans and bottles. To make it easier for the grocery stores to handle the goods in the future, all distribution of drinks ought to be directly delivered to the grocery stores own separate central warehouse. This means every brewery ought to instead supply their drinks to the grocery stores central warehouse instead of taking them directly to the grocery stores. The drinks will then be distributed from the central warehouse to the grocery stores in connection with their orders of provisions. Due to hygienic reasons it is not possible that the deposited units are transported together with the provision.Therefore a kind of recycle drive needs to be organized. By using computer-aided route planning systems every transport are optimized, which means the transportation and labour costs will be reduced. At the same time the strain on the environment will also be a reduced. The company, DPS Europe, an international supplier of professional designed route planning systems. They have assisted with computer software and support during the study. The software PlanLogix build optimized drive routes based on different presumptions, restrictions and parameters which is based on information given by Returpack, responsible for the Swedish bottle refund system. A week’s work requires 19 shifts, three shifts on every work day and two shifts on the weekends. How many times the deposited units need to be collected varies between each grocery store. It differs from seven times a week to one time every forth week. This will lead to a four-week schedule with 76 routes. The total cost for the bottle refund system is 603 459 SEK/four weeks, and the filling degree on the vehicles will be approximately 50 percent. If a bottle refund system is to be implemented it needs to be profitable for the environment, meaning the positive effects need to exceed the negative effects, which the transports cause. To implement deposit drives, the units of aluminum-cans and bottles needs to be higher so the filling degree increases. A proposal to increase the filling degree could be to decrease the number of times each grocery store gets their deposits collected. This will increase the filling degree since at every occasion there will be more units to collect and at the same time decrease the transportation. / Rapporten är det avslutande momentet av utbildningen Industriell Organisation och Ekonomi med inriktning Logistik och Ledning vid Jönköpings Tekniska Högskola. Målet med examensarbetet är att planera och utforma rutter utifrån förutbestämda kriterier, för returkörningar av pantade PET-flaskor och aluminiumburkar från livsmedelsbutiker i Jönköpings län med omnejd. I dagsläget distribueras konsumtionsfärdig dryck i aluminiumburkar och PET-flaskor till butiker med bryggeriernas egna distributörer som i samband med leveransen tömmer butikernas lager av pantade enheter. Men för att underlätta godshanteringen hos handlarna ska i framtiden distributionen istället ske till livsmedelskedjornas olika centrallager och därifrån distribueras tillsammans med butikens beställning av livsmedel. På grund av hygieniska skäl kan butikens pantade enheter inte samköras medlivsmedel vilket kräver att någon form av returkörning samordnas. Genom att använda datorstödd ruttplanering optimeras transporterna vilket betyder att transportkostnader och arbetskostnader minimeras samtidigt som miljöpåverkan reduceras. Företaget DPS Europe är en internationell leverantör av professionella ruttplaneringssystem som bistått med programvara och support. Med hjälp av programmet PlanLogix, från DPS Europe, har optimala körrutter byggts upp utifrån olika förutsättningar, begränsningar och parametrar baserade på information från Returpack, som ansvarar för det svenska pantsystemet. Det krävs 19 arbetsskift i veckan, tre skift på vardagar och två skift på helger, för att samtliga butiker ska få sina lager av pantade enheter tömda. Hämtningsfrekvensen hos butikerna varierar från sju gånger i veckan till en gång var fjärde vecka, vilket resulterar i att ett fyraveckorsschema med totalt 76 rutter skapas. Totalkostnaden är 603 459 kronor/fyra veckor och den använda lastkapaciteten på fordonen är 50 procent. Om ett retursystem ska användas måste det vara miljölönsamt, det vill säga att de positiva effekterna med retursystemet måste vara fler än de negativa konsekvenserna som ökade transporter medför. För att det ska bli försvarbart och lönsamt att utföra returkörningar för PET-flaskor och aluminiumburkar krävs en högt utnyttjande av lastkapacitet. Ett förslag som ökar utnyttjandet av lastkapaciteten är att minska butikernas hämtningsfrekvens så att det vid varje hämtningstillfälle finns mer pantande enheter att hämta. På så sätt ökar den använda lastkapaciteten samtidigt som transportsträckan reduceras.
54

Ruttplanering : Retursystem för pantade PET-flaskor och aluminiumburkar / Route planning : Recycle system for deposit bottles and aluminium cans

Nilsson, Carl, Johansson, Sofie January 2008 (has links)
<p>This report is the final part within our education, Industrial Organization and Economy focusing on Logistics and Management at Jönköping School of Engineering. The aim with this report is to coordinate recycle drives for deposited aluminum-cans and bottles collected from grocery stores within Jönköping county and locality.</p><p>In the present situation both aluminum cans and bottles filled with drinks are distributed to the grocery stores by the brewery’s own distributers. At the same time as they supply the drinks they also discharge the grocery stores units with restored aluminumcans and bottles. To make it easier for the grocery stores to handle the goods in the future, all distribution of drinks ought to be directly delivered to the grocery stores own separate central warehouse. This means every brewery ought to instead supply their drinks to the grocery stores central warehouse instead of taking them directly to the grocery stores. The drinks will then be distributed from the central warehouse to the grocery stores in connection with their orders of provisions. Due to hygienic reasons it is not possible that the deposited units are transported together with the provision.Therefore a kind of recycle drive needs to be organized.</p><p>By using computer-aided route planning systems every transport are optimized, which means the transportation and labour costs will be reduced. At the same time the strain on the environment will also be a reduced. The company, DPS Europe, an international supplier of professional designed route planning systems. They have assisted with computer software and support during the study. The software PlanLogix build optimized drive routes based on different presumptions, restrictions and parameters which is based on information given by Returpack, responsible for the Swedish bottle refund system.</p><p>A week’s work requires 19 shifts, three shifts on every work day and two shifts on the weekends. How many times the deposited units need to be collected varies between each grocery store. It differs from seven times a week to one time every forth week. This will lead to a four-week schedule with 76 routes. The total cost for the bottle refund system is 603 459 SEK/four weeks, and the filling degree on the vehicles will be approximately 50 percent.</p><p>If a bottle refund system is to be implemented it needs to be profitable for the environment, meaning the positive effects need to exceed the negative effects, which the transports cause. To implement deposit drives, the units of aluminum-cans and bottles needs to be higher so the filling degree increases. A proposal to increase the filling degree could be to decrease the number of times each grocery store gets their deposits collected. This will increase the filling degree since at every occasion there will be more units to collect and at the same time decrease the transportation.</p> / <p>Rapporten är det avslutande momentet av utbildningen Industriell Organisation och Ekonomi med inriktning Logistik och Ledning vid Jönköpings Tekniska Högskola. Målet med examensarbetet är att planera och utforma rutter utifrån förutbestämda kriterier, för returkörningar av pantade PET-flaskor och aluminiumburkar från livsmedelsbutiker i Jönköpings län med omnejd.</p><p>I dagsläget distribueras konsumtionsfärdig dryck i aluminiumburkar och PET-flaskor till butiker med bryggeriernas egna distributörer som i samband med leveransen tömmer butikernas lager av pantade enheter. Men för att underlätta godshanteringen hos handlarna ska i framtiden distributionen istället ske till livsmedelskedjornas olika centrallager och därifrån distribueras tillsammans med butikens beställning av livsmedel. På grund av hygieniska skäl kan butikens pantade enheter inte samköras medlivsmedel vilket kräver att någon form av returkörning samordnas.</p><p>Genom att använda datorstödd ruttplanering optimeras transporterna vilket betyder att transportkostnader och arbetskostnader minimeras samtidigt som miljöpåverkan reduceras. Företaget DPS Europe är en internationell leverantör av professionella ruttplaneringssystem som bistått med programvara och support. Med hjälp av programmet PlanLogix, från DPS Europe, har optimala körrutter byggts upp utifrån olika förutsättningar, begränsningar och parametrar baserade på information från Returpack, som ansvarar för det svenska pantsystemet.</p><p>Det krävs 19 arbetsskift i veckan, tre skift på vardagar och två skift på helger, för att samtliga butiker ska få sina lager av pantade enheter tömda. Hämtningsfrekvensen hos butikerna varierar från sju gånger i veckan till en gång var fjärde vecka, vilket resulterar i att ett fyraveckorsschema med totalt 76 rutter skapas. Totalkostnaden är 603 459 kronor/fyra veckor och den använda lastkapaciteten på fordonen är 50 procent.</p><p>Om ett retursystem ska användas måste det vara miljölönsamt, det vill säga att de positiva effekterna med retursystemet måste vara fler än de negativa konsekvenserna som ökade transporter medför. För att det ska bli försvarbart och lönsamt att utföra returkörningar för PET-flaskor och aluminiumburkar krävs en högt utnyttjande av lastkapacitet. Ett förslag som ökar utnyttjandet av lastkapaciteten är att minska butikernas hämtningsfrekvens så att det vid varje hämtningstillfälle finns mer pantande enheter att hämta. På så sätt ökar den använda lastkapaciteten samtidigt som transportsträckan reduceras.</p>
55

Uma técnica híbrida para geração de rotas em espaço geográfico com obstáculos. / A hybrid technique for generating routes in geographical space with obstacles.

Angelo Furtado Picanço 11 September 2012 (has links)
Este trabalho está inserido no campo da Geomática e se concentra, mais especificamente, no estudo de métodos para exploração e seleção de rotas em espaços geográficos sem delimitação prévia de vias trafegáveis. As atividades que poderiam se beneficiar de estudos desse tipo estão inseridas em áreas da engenharia, logística e robótica. Buscou-se, com as pesquisas realizadas nesse trabalho, elaborar um modelo computacional capaz de consultar as informações de um terreno, explorar uma grande quantidade de rotas viáveis e selecionar aquelas rotas que oferecessem as melhores condições de trajetória entre dois pontos de um mapa. Foi construído um sistema a partir do modelo computacional proposto para validar sua eficiência e aplicabilidade em diferentes casos de estudo. Para que esse sistema fosse construído, foram combinados conceitos de sistemas baseados em agentes, lógica nebulosa e planejamento de rotas em robótica. As informações de um terreno foram organizadas, consumidas e apresentadas pelo sistema criado, utilizando mapas digitais. Todas as funcionalidades do sistema foram construídas por meio de software livre. Como resultado, esse trabalho de pesquisa disponibiliza um sistema eficiente para o estudo, o planejamento ou a simulação de rotas sobre mapas digitais, a partir de um módulo de inferência nebuloso aplicado à classificação de rotas e um módulo de exploração de rotas baseado em agentes autônomos. A perspectiva para futuras aplicações utilizando o modelo computacional apresentado nesse trabalho é bastante abrangente. Acredita-se que, a partir dos resultados alcançados, esse sistema possa ajudar a reduzir custos e automatizar equipamentos em diversas atividades humanas. / This research is placed in the field of Geomatics and focuses more specifically on the study of methods for exploration and route selection in geographic areas without prior definition of trafficable roads. Activities that could benefit from such studies are embedded in areas of engineering, logistics and robotics. This study aimed to develop a computational model able to select information from a terrain, explore a lot of viable routes and select those routes that offer the best possible path between two points on a map. It was built a system from the proposed computational model to validate its effectiveness and applicability in different case studies. For this system to be built concepts of agent-based systems, fuzzy logic and route planning in robotics were combined. The information about land were organized, presented and consumed by the system created using digital maps. All features of the system were built using open source. As a result, this research provides an efficient system for the study, planning or route simulation on digital maps, using a fuzzy inference module applied to the classification of routes and a module to operate routes based on autonomous agents. The perspective for future applications using the computational model presented in this study is quite comprehensive. It is believed that from the results, this system can help reduce costs and automate equipment in various human activities.
56

Uma técnica híbrida para geração de rotas em espaço geográfico com obstáculos. / A hybrid technique for generating routes in geographical space with obstacles.

Angelo Furtado Picanço 11 September 2012 (has links)
Este trabalho está inserido no campo da Geomática e se concentra, mais especificamente, no estudo de métodos para exploração e seleção de rotas em espaços geográficos sem delimitação prévia de vias trafegáveis. As atividades que poderiam se beneficiar de estudos desse tipo estão inseridas em áreas da engenharia, logística e robótica. Buscou-se, com as pesquisas realizadas nesse trabalho, elaborar um modelo computacional capaz de consultar as informações de um terreno, explorar uma grande quantidade de rotas viáveis e selecionar aquelas rotas que oferecessem as melhores condições de trajetória entre dois pontos de um mapa. Foi construído um sistema a partir do modelo computacional proposto para validar sua eficiência e aplicabilidade em diferentes casos de estudo. Para que esse sistema fosse construído, foram combinados conceitos de sistemas baseados em agentes, lógica nebulosa e planejamento de rotas em robótica. As informações de um terreno foram organizadas, consumidas e apresentadas pelo sistema criado, utilizando mapas digitais. Todas as funcionalidades do sistema foram construídas por meio de software livre. Como resultado, esse trabalho de pesquisa disponibiliza um sistema eficiente para o estudo, o planejamento ou a simulação de rotas sobre mapas digitais, a partir de um módulo de inferência nebuloso aplicado à classificação de rotas e um módulo de exploração de rotas baseado em agentes autônomos. A perspectiva para futuras aplicações utilizando o modelo computacional apresentado nesse trabalho é bastante abrangente. Acredita-se que, a partir dos resultados alcançados, esse sistema possa ajudar a reduzir custos e automatizar equipamentos em diversas atividades humanas. / This research is placed in the field of Geomatics and focuses more specifically on the study of methods for exploration and route selection in geographic areas without prior definition of trafficable roads. Activities that could benefit from such studies are embedded in areas of engineering, logistics and robotics. This study aimed to develop a computational model able to select information from a terrain, explore a lot of viable routes and select those routes that offer the best possible path between two points on a map. It was built a system from the proposed computational model to validate its effectiveness and applicability in different case studies. For this system to be built concepts of agent-based systems, fuzzy logic and route planning in robotics were combined. The information about land were organized, presented and consumed by the system created using digital maps. All features of the system were built using open source. As a result, this research provides an efficient system for the study, planning or route simulation on digital maps, using a fuzzy inference module applied to the classification of routes and a module to operate routes based on autonomous agents. The perspective for future applications using the computational model presented in this study is quite comprehensive. It is believed that from the results, this system can help reduce costs and automate equipment in various human activities.
57

Trajectory and Pulse Optimization for Active Towed Array Sonar using MPC and Information Measures

Ekdahl Filipsson, Fabian January 2020 (has links)
In underwater tracking and surveillance, the active towed array sonar presents a way of discovering and tracking adversarial submerged targets that try to stay hidden. The configuration consist of listening and emitting hydrophones towed behind a ship. Moreover, it has inherent limitations, and the characteristics of sound in the ocean are complex. By varying the pulse form emitted and the trajectory of the ship the measurement accuracy may be improved. This type of optimization constitutes a sensor management problem. In this thesis, a model of the tracking scenario has been constructed derived from Cramér-Rao bound analyses. A model predictive control approach together with information measures have been used to optimize a filter's estimated state of the target. For the simulations, the MATLAB environment has been used. Different combinations of decision horizons, information measures and variations of the Kalman filter have been studied. It has been found that the accuracy of the Extended Kalman filter is too low to give consistent results given the studied information measures. However, the Unscented Kalman filter is sufficient for this purpose.
58

Understanding social and community dynamics from taxi GPS data / Exploration de la dynamique sociale et collective en utilisant les données GPS de taxi

Chen, Chao 04 July 2014 (has links)
Taxis équipés de capteurs GPS sont un dispositif sensoriel important pour examiner les mouvements et les activités des gens. Dans cette thèse, nous cherchons à découvrir les facettes cachées en ce qui concerne les dynamiques sociales et communautaires codés dans les données de taxi GPS pour mieux comprendre comment se comporte la population urbaine et la dynamique résultant de la ville. Comme certains « aspects cachés» sont en ce qui concerne l'aspect similaire de la dynamique sociale et de la communauté, nous avons encore définissons formellement trois catégories pour l'étude, et les explorer à combler les écarts importants entre la première circuler des données GPS et des applications innovantes et des services urbains intelligents. Plus précisément, 1. Pour permettre aux applications d'alertes de fraude de taxi en temps réel, nous vous proposons algorithme iBoat qui est capable de détecter des trajectoires anormales "à la volée " et déterminer quelles parties de la trajectoire sont responsables de sa "anomalousness", en les comparant historiquement trajectoires ayant la même origine et de destination. 2. Pour introduire des services de transport respectueux de l'environnement aux citoyens rentable et, nous vous proposons B -Planner qui est une approche en deux phases, à planifier des itinéraires de bus de nuit bi- directionnelles de levier grands taxis données GPS. 3. Afin d'offrir un système de planification voyage d'itinéraire personnalisé, interactif, et le trafic-courant pour les utilisateurs, nous proposons système Tripplanner qui contient à la fois hors ligne et des procédures en ligne, en s'appuyant sur une combinaison de géolocalisation réseau social et des ensembles de données de taxi GPS. Enfin, certaines directions de recherche prometteuses pour les travaux futurs sont signalées, qui tentent essentiellement de fusionner les données de taxi GPS avec d'autres ensembles de données pour fournir des services urbains plus intelligents et personnalisés / Taxis equipped with GPS sensors are an important sensory device for examining people’s movements and activities. They are not constrained to a pre-defined schedule/route. Big taxi GPS data recording the spatio-temporal traces left by taxis provides rich and detailed glimpse into the motivations, behaviours, and resulting dynamics of a city’s mobile population through the road network. In this dissertation, we aim to uncover the “hidden facets” regarding social and community dynamics encoded in the taxi GPS data to better understand how urban population behaves and the resulting dynamics in the city. As some “hidden facets” are with regard to similar aspect of social and community dynamics, we further formally define three categories for study (i.e. social dynamics, traffic dynamics, and operational dynamics), and explore them to fill the wide gaps between the raw taxi GPS data and innovative applications and smart urban services. Specifically, 1. To enable applications of real-time taxi fraud alerts, we propose iBOAT algorithm which is capable of detecting anomalous trajectories “on-the-fly” and identifying which parts of the trajectory are responsible for its anomalousness, by comparing them against historically trajectories having the same origin and destination. 2. To introduce cost-effective and environment-friendly transport services to citizens, we propose B-Planner which is a two-phase approach, to plan bi-directional night bus routes leveraging big taxi GPS data. 3. To offer a personalized, interactive, and traffic-aware trip route planning system to users, we propose TripPlanner system which contains both offline and online procedures, leveraging a combination of Location-based Social Network (i.e. LBSN) and taxi GPS data sets. Finally, some promising research directions for future work are pointed out, which mainly attempt to fuse taxi GPS data with other data sets to provide smarter and personalized urban services for citizens
59

Route Planning of Battery Electric Heavy-Duty Commercial Vehicles : Using Contraction Hierarchies and Mixed Integer Programming

Delborg, Olle, Insulander, Elias January 2023 (has links)
This thesis addresses route planning of Battery Electric Heavy-Duty Commercial Vehicles to enhance the reliability of electric vehicle transport. Collaborating with Scania, a Swedish truck manufacturing company, the goal is to develop a pipeline that uses open source data from OpenStreetMap and performs a modified Contraction Hierarchy in order to create a graph that can be used as input to a modified Vehicle Routing Problem formulation using Mixed Integer Programming. The input graph is preprocessed to support a Battery Electric Heavy-Duty Commercial Vehicle model in order to more accurately predict energy consumption. The challenges lie in balancing computational efficiency and electric vehicle characteristics. The implemented pipeline demonstrates success but initial tests show that a naive version of the pipeline, not implementing Contraction Hierarchies, can perform better. Several speedups can be made in order to improve the efficiency of the pipeline, the main being in programming in a more efficient programming language than Python. Further testing is needed for larger input graphs to assess performance accurately.
60

Exploring algorithms to score control points in metrogaine events

Van Hoepen, Wilhelmina Adriana 02 1900 (has links)
Metrogaining is an urban outdoor navigational sport that uses a street map to which scored control points have been added. The objective is to collect maximum score points within a set time by visiting a subset of the scored control points. There is currently no metrogaining scoring standard, only guidelines on how to allocate scores. Accordingly, scoring approaches were explored to create new score sets by using scoring algorithms based on a simple relationship between the score of, and the number of visits to a control point. A spread model, which was developed to evaluate the score sets, generated a range of routes by solving a range of orienteering problems, which belongs to the class of NP-hard combinatorial optimisation problems. From these generated routes, the control point visit frequencies of each control point were determined. Using the visit frequencies, test statistics were subsequently adapted to test the goodness of scoring for each score set. The ndings indicate that the score-visits relationship is not a simple one, as the number of visits to a control point is not only dependent on its score, but also on the scores of the surrounding control points. As a result, the scoring algorithms explored were unable to cope with the complex scoring process uncovered. / Decision Sciences / M. Sc. (Operations Research)

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