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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.
461

Individualisation of a Driver Coaching Service : Combining Design Ethnography and Service Design to Gain Insights About the Coaches’ Role and Activities

Rosenqvist, Rebecka, Wikström, Maria January 2018 (has links)
Services surround us every day and companies all over the world have to adapt to the demand of services to make their products more successful and attractive. This master thesis has, on behalf of Scania in Södertälje, Sweden, focused on the service Driver coaching, a service where drivers are dedicated a personal coach who gives regular calls to the drivers. The aim of the thesis was to explore how a driver coaching service could be individualised to each driver. Furthermore, the aim was to develop a design proposal for Driver coaching that creates value for both coaches and drivers. Three coaches from Sweden, Finland and Norway were observed and interviewed to identify what role the coaches have in the service and all the activities they perform. During the analysis of the ethnographic findings, explorations were made on whether valuable insights can be found by interpreting the data with service design visualisations. A customer journey was created which catalysed the analysis phase and helped to generate insights in which pain points could be identified. Three important themes that emerged from the insights were individualisation, trust and communication. Insights from the ethnographic findings and the literature review show that a driver coaching service should, in fact, be individualised. The design proposal that was developed enables different arrangements of the service, which fit each driver’s needs and goals, with the help of a driver profile. Conclusions include information about what is important to think about when designing a driver coaching service that is individualised. Lastly, the thesis contributes to research with lessons learned about how ethnographic data can be used in a generative service design process.
462

Rankine cycle based waste heat recovery system applied to heavy duty vehicles : topological optimization and model based control / Récupération de chaleur par cycle de Rankine dans un véhicule poid lourd : optimisation topologique et commande

Grelet, Vincent 18 January 2016 (has links)
L’évolution croissante du prix des carburants ainsi que les normes antipollution de plus en plus drastiques obligent les fabricants de véhicules commerciaux à développer des solutions innovantes pour réduire la consommation de carburant. Dans cet objectif, comme une grande partie de l’énergie contenue dans le carburant est directement relâchée à l’ambient sous forme de chaleur, celle-ci peut être valorisée et transformée via un cycle thermodynamique secondaire. Dans ce cadre, l’importante utilisation du cycle de Rankine à travers le monde en font un candidat naturel pour une implémentation dans un véhicule. Mais contrairement à une utilisation stationnaire, de nombreux obstacles se dressent pour une intégration totale dans un poids lourd. De nombreuses études ont été menées ces trente dernières années afin de déterminer le potentiel réel d’un tel système une fois embarqué à bord d’un véhicule. Les nombreuses sources de chaleur valorisables, les contraintes inhérentes à l’application embarquée ou encore les forts régimes transitoires induits par l’utilisation du camion doivent mener à une optimisation à la fois de l’architecture du système ainsi que de son système de contrôle. L’optimisation du système mène à un choix en terme de sources chaudes et froides, de topologie, de fluide de travail ainsi que de dimensionnement des composants afin de maximiser les performances. Le système de contrôle joue lui un rôle primordial afin de tirer un bénéfice maximum d’un tel système connaissant ses limites physiques ainsi que d’assurer une utilisation efficace. Dans cette thèse, une méthodologie de conception d’un système de valorisation des rejets thermiques est proposée. En se basant sur des simulations du véhicule complet basées sur un modèle détaillé, les thématiques de la sélection du fluide de travail, des sources chaudes et froides ainsi que l’optimisation des composants et du cycle sont approchées. Par la suite, le problème de contrôle en ligne de la surchauffe à la sortie de l’évaporateur est formalisé. En tenant compte des contraintes numériques d’implémentation, différentes stratégies de commande sont mises en place, allant du contrôleur PID à des structures plus avancées telle que la commande prédictive par modèle ou une loi de commande basée sur un observateur. La plupart de ces stratégies sont validées expérimentalement sur un banc d’essai mis en place durant la thèse / The constant evolution of oil prices and the more and more stringent automotive emission standards force the original engine manufacturers to search for innovative solutions in order to reduce oil consumption. As an important part of the energy contained in the primary carrier (the fuel) is lost to the ambient through heat, it seems convenient to recover a part of this thermal energy and to turn it into fuel consumption reduction. Thermodynamic bottoming cycle such as the Rankine cycle could be used to meet this objective. Its popular use throughout the world for electricity generation makes it a natural candidate for on-board implementation in vehicles. However, a certain number of hurdles are still present before the system can be efficiently applied to heavy-duty trucks. In the last thirty years, numerous studies heave been carried out to evaluate the real potential of that kind of system on a vehicle but nothing has yet been commercialized. The heat sources to recover from, the constraints relative to the on-board application and the long and frequent transient behavior of the vehicle mean both the system architecture and its control strategy need to be optimized. The system optimization leads to a choice in terms of working fluid, heat sources and sinks, and components sizing in order to maximize power recovery and hence the fuel saving. The control plays a major role by using the capability of such a system to ensure an efficient and safe operation and limiting the interactions with the other vehicle sub-systems. In this thesis, a system design methodology is introduced to optimize the system architecture using complete model-based vehicle simulation. The constraints relative to the mobile application are taken into consideration to evaluate the potential of such a system. Modelbased control strategies for on controlled variable, namely the superheat level, are developed. Constrained by the implementation platform, different control frameworks ranging from PID to model predictive controllers or observer based controllers are developed to fit into a normal automotive electronic control unit. Most of these novel strategies were experimentally validated on a test rig developed during the thesis
463

Perfil dos riscos cardiovasculares em motoristas profissionais de transporte de cargas da Rodovia BR-116 no trecho Paulista-Régis Bittencourt / Cardiovascular risk profile observed in professional truck drivers who work on Highway BR116 within the area of the state of São Paulo-Régis Bittencourt

Luciane Cesira Cavagioni 14 December 2006 (has links)
Introdução: As doenças cardiovasculares constituem a principal causa demorbimortalidade nacional. Nesse sentido realizou-se estudo com o objetivo de caracterizar o perfil para riscos cardiovasculares em motoristas profissionais de transporte de cargas que trafegam pela Br-116. Casuística e Método: Estudo transversal, descritivo e exploratório com 258 motoristas profissionais de transporte de cargas com obtenção de informações socioeconômicas; avaliações antropométricas: índice de massa corporal (IMC), circunferência abdominal e medida da pressão arterial; realização de exames laboratoriais: triglicérides, colesterol total e frações, proteína C reativa e creatinina. Analisou-se o risco para doenças cardiovasculares pelo Escore de Risco de Framingham, consumo de bebidas alcoólicas pelo Alcohol Use Disorders Identification-AUDIT, distúrbios psiquiátricos comuns pelo Self Report Questionnaire-SRQ-20, Síndrome Metabólica e angina pectoris pelo Teste de Rose. Os dados foram processados no sistema SPSS v.7.5. O nível de significância adotado foi p<0,05, utilizou-se análise univariada e multivariada. Resultados: A caracterização os motoristas estudados mostrou idade 37,5±10,1 anos, 91% de etnia branca, renda mensal 1.431,3±644,4 reais, 19% tabagistas, 55% referiram ingestão de bebidas alcoólicas, 74% não realizavam atividade físicas, 14% relataram uso de medicamentos inibidores do sono, tempo profissão de 14±10 anos e percorriam 782,9±229,6 km/dia, dirigiam 10 horas por dia e repousavam 06 horas diárias. Verificou-se pelos dados antropométricos que 46% tinham sobrepeso, 36% obesidade e 58% circunferência abdominal alterada (_94 cm). Os exames laboratoriais mostraram 33% com nível de colesterol total _ 200mg/dL, 10% LDL-c _ 160 mg/dL; HDL-c < 40 mg/dL 23%, triglicérides acima de 150 mg/dL 38%, glicemia _ 110mg/dL 7% e proteína C reativa > 0,5 mg/dL 19%, creatinina >1,5 mg/dL 1%. A prevalência da hipertensão arterial foi de 37% e da Síndrome metabólica 24%. O Questionnaire Rose foi positivo em 8,0% dos motoristas, Escore de Risco de Framingham médio/alto em 9%, presença de distúrbios psiquiátricos comuns em 33% e AUDIT 16% no escore que sugere intervenção e aconselhamento. A análise de regressão logística indicou associação independente para as seguintes variáveis (OD Odds ratio, IC intervalo de confiança a 95%): 1-Síndrome Metabólica: IMC (OR=1,40 IC 1,192-1,661); hábito de verificar o colesterol total (OR= 0,102 IC 0,017-0,589); e escore de risco de Framingham médio/alto (OR= 26,389 IC 2,520-276,374). 2-Hipertensão arterial: IMC (OR=1,183 IC 1,065-1,314); glicemia (OR=1,039 IC 1,004-1,076); e hábito de ingerir medicamento para inibir o sono (OR= 0,322 IC 0,129-0,801). 3- Colesterol Total (_ 200 mg/dL): LDL-c (OR=1,157 IC 1,100-1,216);triglicérides (OR=1,012 IC 1,004-1,021) 4- Glicemia (_ 110 mg/dL): IMC (OR=1,153 IC 1,024-1,298); maior tempo de profissão (OR=1,154 IC 1,057-1,259) 5-Proteína C reativa (>0,5 mg/dL): escore de risco de Framingham médio/alto (OR=4,692 IC 1,912-11,515). Conclusão: Verificou-se presença expressiva de fatores de risco cardiovasculares, nesse sentido os profissionais de saúde devem implementar estratégias para estimular mudanças de estilos de vida nos motoristas de transporte de cargas, visando a prevenção primária e secundária / Introduction: Cardiovascular diseases are the main cause of morbidity and mortality in Brazil. Therefore, a study aiming at characterizing the cardiovascular risk profile observed in professional truck drivers who work on Highway Br-116 was carried out. Population and Method: An exploring, descriptive and transversal study with 258 professional truck drivers, social economical information, both body mass index (BMI) and waist circumference evaluations, blood pressure measurement, as well as laboratory test performance: triglycerides, total and fraction cholesterol, and C reactive protein. The risk for cardiovascular diseases was assessed by Framingham scores; alcohol intake by Alcohol Use Disorders Identification-AUDIT; common psychiatric disorders by Self Report Questionnaire-SRQ-20; and angine pectoris by Rose´s test Data were processed in the SPSS system v.7.5, considering that the significance level adopted was 0,05, and univaried and multivaried analyses were used. Results: The characterization of the drivers studied revealed age of 37.5±10.1 years, 91% of them were white, monthly income 1.431,3 ± 644,4 reais (Brazilian currency), 19% were smokers, 55% referred alcohol intake, 74% did not make physical exercises, 14% referred using sleeping inhibitor drugs, professional time 14±10 years and used to drive 782,9±229,6 Km/day. It was observed that 46% of them were overweight and 36% were obese and 58% had altered waist circumference (_ 94 cm) by the anthropometric data. The lab tests showed 33% with total cholesterol level _200 mg/dL, 10% LDLc _160 mg/dL, HDL-c <40 mg/dL 23%, triglycerides over 150 mg/dL 38%, glycemy _110mg/dL 7%, and C reactive protein >0.5 mg/dL 19%. The prevalence of hypertension was 37% and of Metabolic Syndrome, 24%. Rose’s test was positive for 8% of the drivers, Medium/High Framingham scores for 9%, presence of common psychiatric disturbs in 33% and 16% with AUDIT score suggesting intervention and advisory. The logistical regression analysis indicated independent association for the following variables: (OR Odds ratio, CI confidence interval at 95%): 1- Metabolic Syndrome: BMI (OR=1,40 CI 1,192-1,661); the habit of checking the total cholesterol (0,102 IC 0,017-0,589); Medium/high Framingham score (OR=26,389 IC 2,520-276,374); 2-Hypertension: BMI (OR=1,183 IC 1,065-1,314); glycemy (OR=1,039 IC 1,004-1,076); the habit of taking sleeping pills (OR=0,322 IC 0,129-0,801). 3- Total Cholesterol (_ 200 mg/dL): LDL-c (OR=1,157 IC 1,100-1,216); triglycerides (OR=1,012 IC 1,004-1,021). 4- Glycemy (_ 110 mg/dL): BMI (OR=1,153 IC 1,024-1,298); professional time (OR=1,154 IC 1,057-1,259). 5- C reactive protein (>0,5 mg/dL): Medium/high Framingham score (OR=4,692 IC 1,912-11,515). Conclusion: It was observed an expressive presence of cardiovascular risk factors. Therefore health professionals should implement strategies to stimulate changes in truck drivers’ lifestyle, aiming at primary and secondary prevention
464

Logistika firmy Gefco / Logistics of company GEFCO

Severová, Petra January 2008 (has links)
My graduation work is focused on logistics aplication at specific provider of logistics services. In theoretical part I describe development of logistics, types and links of supply chain and supply chain in automotive industry. In my application part I describe company GEFCO and car producer TPCA. I analyse present situation, standard and non-standard activities solved by department GEFCO Overland. Next I appreciate questionnaire survey, where I find out hot company's problems and try to give their solution that can increase effectivity, decrease costs and provide more valuable services to company's customers.
465

Modelling and control of an articulated underground mining vehicle

Kohlmeyer, Rolf Reimar 12 July 2012 (has links)
The automation of the tramming or load, haul and dump (LHD) procedure, performed by a LHD vehicle, holds the potential to improve productivity, efficiency and safety in the mining environment. Productivity is mainly increased by longer working hours; efficiency is improved by repetitive, faultless and predictable work; and safety is improved by removing the human operator from the harsh environment. However, before the automation of the process can be addressed, a thorough understanding of the process and its duty in the overall mining method is required. Therefore, the current applicable mining methods and their areas of potential automation are given. Since the automation of the LHD vehicle is at the core of this project, its implementation in the tramming process is also justified. Also, the current underground navigation methods are given and their shortcomings are named. It is concluded that infrastructure-free navigation is the only viable solution in the ever-changing mining environment. With that in mind, the feasibility of various navigation sensors is discussed and conclusions are drawn. Both kinematic and dynamic modelling of LHD vehicles are introduced. Various forms of kinematic models are given and their underlying modelling assumptions are named. The most prominent assumptions concern the vehicle’s half-length and the inclusion of a wheel-slip factor. Dynamic modelling techniques, with a strong emphasis on tyre modelling, are also stated. In order to evaluate the modelling techniques, field tests are performed on the articulated vehicles, namely the Wright 365 LHD and the Bell 1706C loader. The test on the Wright 365 LHD gives a good impression of the harsh ergonomics under which the operator has to work. A more thorough test is performed on the Bell 1706C articulated loader. The test results are then compared to simulation results obtained from the kinematic models. Also, the above-named assumptions are tested, evaluated and discussed. A dynamic model is also simulated and discussed. Lastly, two localization and control methods are given and evaluated. The first method is an open-loop nonlinear optimal control strategy with periodic position resetting and the second method is a pathtracking controller. AFRIKAANS : Automatisering van die laai-, vervoer- en dompel- (LVD) prosedure het die potensiaal om die produktiwiteit, effektiwiteit en veiligheid van die mynbedryf te verbeter. Produktiwiteit word hoofsaaklik deur langer werksure verhoog, effektiwiteit word deur herhalende, foutlose en voorspelbare werk verbeter en veiligheid word verbeter omdat menslike operateurs uit die gevaarlike ondergrondse omgewing verwyder word. Voordat aandag aan die automatisering van die prosedure geskenk kan word, moet die prosedure en die algemene mynbedrywighede rakende die prosedure deeglik bestudeer en verstaan word. As gevolg hiervan word die huidige, toepaslike mynboumetodes hier gedokumenteer. Die implementering van ʼn gekoppelde LVD-voertuig in die LVD-prosesword ook geregverdig. Verder word die huidige metodes van ondergrondse navigasie genoem en hulle tekortkominge aangedui. Die gevolgtrekking dat infrastruktuur-vrye navigasie die enigste lewensvatbare navigasiemetode in die immer veranderende ondergrondsemynbouomgewing is, word ook gemaak. In die lig daarvan word ʼn verskeidenheid sensors genoem en bespreek. Kinematiese en dinamiese modellering van ʼn LVD-voertuig word bekendgestel. Verskeie kinematiese modelle en hulle onderliggende aannames word genoem. Die mees prominente aannames is die lengte van die gekoppelde voertuig se hoofdele en die insluiting van ʼn wielglipfaktor. Die tegnieke van dinamiese modellering, met die klem op bandmodellering, word ook gegee. Praktyktoetse op gekoppelde voertuie is ook gedoen om die verskillende modelle te evalueer. Die toets op die Wright 365-LVD bied goeie insig in die strawwe ergonomiese toestande waaronder die operateurs moet werk. ʼn Deeglike toets is op ʼn BELL 1706C- gekoppelde laaier, wat kinematies identies aan ʼn LVD-voertuig is, uitgevoer. Die bevindinge van die toets word met bogenoemde modelsimulasies vergelyk en gevolgtrekkings word gemaak. Laastens word lokalisiering en beheer van ʼn LVDvoertuig behandel. Twee beheermetodes, opelus- nie-lineêre optimale beheer met periodieke herstel en padvolgingbeheer word geëvalueer en bespreek. Copyright / Dissertation (MEng)--University of Pretoria, 2012. / Electrical, Electronic and Computer Engineering / unrestricted
466

Predictive Energy Management of Long-Haul Hybrid Trucks : Using Quadratic Programming and Branch-and-Bound

Jonsson Holm, Erik January 2021 (has links)
This thesis presents a predictive energy management controller for long-haul hybrid trucks. In a receding horizon control framework, the vehicle speed reference, battery energy reference, and engine on/off decision are optimized over a prediction horizon. A mixed-integer quadratic program (MIQP) is formulated by performing modelling approximations and by including the binary engine on/off decision in the optimal control problem. The branch-and-bound algorithm is applied to solve this problem. Simulation results show fuel consumption reductions between 10-15%, depending on driving cycle, compared to a conventional truck. The hybrid truck without the predictive control saves significantly less. Fuel consumption is reduced by 3-8% in this case. A sensitivity analysis studies the effects on branch-and-bound iterations and fuel consumption when varying parameters related to the binary engine on/off decision. In addition, it is shown that the control strategy can maintain a safe time gap to a leading vehicle. Also, the introduction of the battery temperature state makes it possible to approximately model the dynamic battery power limitations over the prediction horizon. The main contributions of the thesis are the MIQP control problem formulation, the strategy to solve this with the branch-and-bound method, and the sensitivity analysis.
467

Detekce a lokalizace pohybujících se objektů / Moving object detection

Škuta, Pavel January 2008 (has links)
The aim of this these was devise a automatic system applications, monitoring entering of motors vechitles with in automaric collection of trafic data. Automatic system allows identify of mooving vechitlses in slow speed and searching of the area registration number. Theoretical analysis of possible kind solving problems detection moving vechitles and their localization. From possible solutions was selected solution by camera systems. Was take a pictures of vechitles, whitch is as true of the real scene. On the pictures was testing of algorithm for detecting of area registraction number of vechitles. Designed system is possible to use for automatic monitoring mooving entering vechitles.
468

Studie nákladů na dopravu v distribuční firmě / The Study of Transportation Costs in Distrubution Company

Malínková, Lenka January 2007 (has links)
The master´s thesis deal with transportation costs occurred in distribution company. It analyses both the evidence and monitoring of the particular costs, and also the range and efficiency of the spent costs. The outcome of my thesis is proposal of the evidence and the methodics for costs´ evaluation during the physical distribution.
469

Návrh okružní křižovatky silnic I/35, I/57 a II/150 při silném levém odbočení / Design of roundabout I/35, I/57 and II/150 with strong left-turn

Mahdal, Jan January 2014 (has links)
The diploma thesis is focused on insufficient capacity problem of roundabout I/35, I/57 and II/150 in the Valašské Meziříčí town. It is based on engineering survey according to which three possible models are designed. Capacity assesment is made on each of these models. Throug the evaluation is selected the most suitable design of turbo roundabout type "knee", which is technically processed and substantiated by text and drawing documentation.
470

Studie přestavby křižovatky silnic I/56 a II/469 v Hlučíně / Location Study of Crossroad of Roads I/56 and II/469 in Hlučín

Škvainová, Aneta January 2014 (has links)
The subject of my Master’s thesis is the variant redevelopment of intersections I/56 and II/469 in Hlučín. Both interesections are situated nearby bus terminal. Extent of adjustment obstructs the object of former granary. There are checked spatial options for adjusting both existing intersections to the roundabouts. In the frame of variants, there is a different manner of solution of structural layout of both intersections, possibility of connection of bus terminal and transfer of pedestrian traffic across designed intersections. Part of Master’s thesis is traffic survey and capacity analysis of designed intersections.

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