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Des sciences humaines aux sciences de l’ingénieur : comportements humains, activités finalisées et conception de systèmes d’assistance à la conduite de véhicules industriels / From human sciences to engineering sciences : human behaviours, finalized activities and design of driving assistance systems for trucksVan Box Som, Annick 14 December 2010 (has links)
La conduite d’un véhicule industriel est une activité professionnelle complexe qui s’exerce dans un environnement dynamique en constante évolution. Elle nécessite un apprentissage spécifique et se situe dans un cadre réglementaire strict, qui relève aussi bien du code du travail que de la réglementation routière. A ces caractéristiques s’ajoutent de fortes contraintes spatio-temporelles qui imposent aux conducteurs le recours à des stratégies opératoires pour répondre à l’objectif principal de leur activité : le respect des délais de livraison dans des conditions optimales de sécurité, de sûreté et de productivité.Cette thèse traite de l'apport de la psychologie cognitive à la conception de systèmes d'assistance à la conduite de véhicules industriels. Les travaux sont destinés à intégrer, dès la conception des nouveaux systèmes, les contraintes du fonctionnement cognitif humain en situation réelle, ainsi que les besoins et attentes des conducteurs, afin que leur soient proposées des solutions technologiques adaptées et utilisables.La partie appliquée illustre deux dimensions majeures de l'activité de conduite d'un camion : la productivité, au travers de la problématique de l'assistance à l'éco-conduite (projet Conduite Economique Assistée, ADEME- RENAULT TRUCKS) ; la sécurité, au travers de la problématique de l'assistance à la détection et à la protection des usagers vulnérables de la route (projet VIVRE2, ANR-PREDIT05-LUTB).D’un point de vue scientifique, la thèse aboutit à la proposition d’un modèle du fonctionnement humain dans les activités finalisées, complété par un modèle adapté à l’activité de conduite d’un véhicule industriel. Les analyses effectuées en situations réelles enrichissent les connaissances, d’une part, sur les stratégies de conduite appliquées à la conduite rationnelle d’un poids lourd en environnement extra-urbain, et, d’autre part, sur les composantes de l’activité des conducteurs qui effectuent des livraisons en milieu urbain. De plus, les travaux effectués dans le cadre du projet VIVRE2 ont permis de préciser les représentations et les comportements à risque des usagers vulnérables vis-à-vis des camions en ville.D’un point de vue applicatif et ergonomique, les travaux sur simulateur dynamique de conduite ont permis l’évaluation d’une interface homme-machine innovante qui pourrait être adaptée à l’éco-conduite, ainsi que la proposition et l’évaluation de systèmes d’assistance pour garantir la sécurité des usagers vulnérables lors des manœuvres à basse vitesse en milieu urbain. / Driving a truck is a complex professional activity that takes place in a dynamic and constant changing environment. It needs a specific learning and it is set in a strict regulated framework including French labour code (Code du travail) as road regulation. Strong spatio-temporal pressure should be added to those characteristics. These constraints entail to drivers the use of operative strategies to achieve the main objective of their activity: respect of delivery time in optimal conditions of safety, security and productivity.This thesis deals with the contribution of cognitive psychology to the design of driving assistance systems for trucks. Works are intended to integrate, from the design of new systems, the demands of human cognitive functioning in real situation and the needs and expectations of drivers so that adapted and usable technological solutions could be proposed to them.Applied part shows two major dimensions of truck driving activity: productivity through the issue of the eco-driving assistance (“Conduite Economique Assistée, ADEME- RENAULT TRUCKS” project) and safety through the issue of the assistance to detection and protection of vulnerable road users (“VIVRE2, ANR-PREDIT05-LUTB” project).From a scientific point of view, the thesis ends with a proposal of a model of human functioning in finalized activities, of which is added an adapted model of the truck driving activity. The analysis performed in real environment enhance knowledge, on the one hand, on the applied driving strategies to the eco-driving of a truck in extra-urban environment and, on the other hand, on the components of the activity of drivers doing deliveries in urban environment. Moreover, works performed in VIVRE2 project allowed to specify representations and risky behaviours of vulnerable users with relation to trucks in town.From an applicative and ergonomic point of view, works on driving dynamic simulator allowed the evaluation of an innovative man-machine interface which could be adapted to eco-driving and the proposal as well as the evaluation of assistance systems to guarantee safety of vulnerable users during low speed manoeuvres in urban environment.
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Seating in Autonomous Trucks : Design of Driver Seating for Autonomous Long Haulage TrucksWikberg, Amanda, Andersson, Therese January 2019 (has links)
The biggest shift in the automotive industry lies ahead. Autonomous vehicles create both curiosity and skepticism among drivers and people around. Autonomous vehicles, more specifically trucks, will not be utterly self-driving overnight. The whole transformation will take place in different phases. When a vehicle does not need a driver behind the wheel, new needs will arise. This is where this project comes into play. On behalf of Scania, a new driver’s seat shall be developed for new needs from the drivers for autonomous trucks of type 4. The project was carried out at Scania’s design department for cabin interiors. The project aimed to develop new needs for the future autonomous level 4 trucks in order to develop a driver’s seat that meets these needs. The project began with a planning phase in which the goals and the time frame for the project were set up. The project was then implemented in four different phases inspired by CDIO (n.d.). The work began with a benchmarking on existing trucks and passenger cars, but also on the future visions of different competitors regarding autonomous vehicles. Much work was put into understanding theories and interpreting relevant information. The users were used early in the project in the form of interviews, observations, and a survey that reached 299 truck drivers. The work then continued with various forms of brainstorming both within the project group and together with engineers from the group at Scania. The final work contained a CAD model of both prototype, CAID models of the final design, and a prototype scale of 1:1. The final result of the project is a new driver’s seat with the possibility of pushing the seat almost three times further back than the current seat. It can now be done when the driver’s seat is part of the bed. During the user study and the brainstorming, new needs were taken from the perspective of the sun being able to adapt to three different positions; rest, drive, work. The new driver’s seat now gives the drivers this opportunity. The result of this project may be more effective in driving the driver, which benefits both Scania and the customers in the form of the drivers being able to drive longer than previously allowed. / Det största skiften inom fordonsbranschen ligger framför oss. Autonoma fordon skapar både nyfikenhet och en skepsis bland förare och människor runt omkring. Autonoma fordon, mer specifikt lastbilar, kommer inte bli helt självkörande under en natt. Hela för- vandlingen kommer ske i olika faser. När ett fordon inte behöver en förare bakom ratten kommer nya behov uppkomma. Det är här det här projektet kommer in i bilden. På uppdrag av Scania, ska en ny förarstol utvecklas för nya behov från förarna för autonoma lastbilar av typen nivå 4. Projektet är ett examensarbete gjort av två studenter vid utbildningen civilingenjör inom teknisk design med inriktning produktutveckling, vid Luleå tekniska universitet. Projektet genomfördes på Scanias konstruktionsavdelning för hyttint- eriör. Målet för projektet var att ta fram nya behov för framtidens autonoma nivå 4 lastbilar för att sedan utveckla en förarstol som uppfyller dessa behov. Projektet började med en planeringsfas där målen och tidsramen för projektet sattes upp. Projektet genomfördes sedan i fyra olika faser inspirerade av CDIO (n.d.). Arbetet började med att en benchmarking gjordes på befintliga lastbilar och personbilar men även på olika konkurrenters framtidsvisioner gällande autonoma fordon. Mycket arbete lades på att förstå teorier och tolka relevant infor- mation. Användarna användes tidigt i projektet i form av intervjuer, observationer och en enkät som nådde ut till 299 lastbilsförare. Arbetet fortsatte sedan med olika former av brainstorming både inom projektgruppen och tillsammans med ingenjörer från gruppen på Scania. Slutgiltiga arbetet innehöll CAD-modeller av både prototyp, CAID-modeller av slutgiltig design samt en prototyp i skala 1:1. Det slutgiltiga resultatet av projektet är en ny förarstol med möjligheten att skjuta bak stolen nästan tre gånger längre än vad som tidigare var möjligt. Det kan nu göras då förarstolen är en del av sängen. Under användarstudien och brainstormingen togs nya behov fram i from av att solen ska ha möjlighet att anpassas till tre olika lägen; vila, köra, arbeta. Den nya förarstolen ger nu förarna den här möjligheten. Resultatet av det här projektet kan komma att effektivisera föraryrket, vilket gynnar både Scania och kunderna i form av att förarna kommer kunna köra längre än vad tidigare varit tillåtet.
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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 BittencourtCavagioni, Luciane Cesira 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%. Roses 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
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Quantifica??o das emiss?es de gases de efeito estufa para ve?culos de coleta de res?duos domiciliares abastecidos com GNV e Diesel-B5 utilizando avalia??o de ciclo de vida (ACV)Costa, Ronaldo Silvestre da 30 November 2016 (has links)
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Previous issue date: 2016-11-30 / Funda??o de Amparo ? Pesquisa do Estado do Rio Grande do Sul (FAPERGS) / The transport sector represents a significant responsibility in the pollution emissions.
Also, the consumption of fossil fuels is related with the rising of global average
temperature due to the greenhouse gas emissions. Biofuels and natural gas are
investigated as alternative fuels to mitigate the environmental impacts. However, due
to the several source emissions within a product life-cycle, the environmental
performance of an environmental friendly product must be verified. This work aims to
quantify greenhouse gas emissions during household waste collection by heavy
vehicles (trucks) fueled with different fuels. It was proposed the development and
implementation of a methodology to compare both pollutant gas emissions and noise
for the use of CNG (compressed natural gas) and diesel-B5, aiming to mitigate
environmental impacts in captive fleet that travels daily in the Porto Alegre city, Rio
Grande do Sul state, Brazil. The trucks were monitored using a portable gas analyzer
equipment (O2, CO, CO2, NO, NO2, NOx, SO2, HC), and the fuel consumptions and
autonomy were obtained from the company that provides the service. With the data
collected on established routes, it was applied the Life Cycle Assessment (LCA)
methodology to carry out the study comparing the environmental performance of the
use of CNG and Diesel-B5. The results showed that higher global warming impact
(according IPCC method) was observed to CNG, independently of the time horizon
considered (20 100 or 500 years). When comparing the contribution of the process
stages (from production to use of fuels), CNG presented higher impacts in the
collection and venting steps, while diesel -- B5 presented in the collection step. / O setor de transportes apresenta significativos problemas ambientais
relacionados ?s emiss?es de poluentes, agravados em regi?es urbanas. A queima e
a explora??o de combust?veis f?sseis s?o constantemente relacionadas ao aumento
da temperatura m?dia global. O uso de combust?veis, como os de origem vegetal e
g?s natural, tem sido uma alternativa frequente na mitiga??o de gases de efeito
estufa. No entanto, devido ?s v?rias fontes de poluentes presentes no ciclo de vida
do produto, o desempenho ambiental de produtos considerados amig?veis ao meio
ambiente deve ser verificado. Este trabalho teve como objetivo quantificar as
emiss?es de gases de efeito estufa emitidos durante a coleta de res?duos
domiciliares por ve?culos pesados (caminh?es) abastecidos com diferentes
combust?veis: g?s natural e diesel-B5. Prop?e-se o desenvolvimento e a
implementa??o de uma metodologia para a compara??o das emiss?es de poluentes
para o uso de GNV (g?s natural veicular) e Diesel-B5, objetivando a mitiga??o de
impactos ambientais em frota cativa que trafega diariamente na cidade de Porto
Alegre ? RS. Os caminh?es foram monitorados com um equipamento analisador
port?til de gases (O2, CO, CO2, NO, NO2, NOx, SO2, HC), e os consumos e a
autonomia dos combust?veis foram obtidos junto ? empresa prestadora do servi?o.
Com os dados levantados nas rotas estabelecidas, foi aplicada a metodologia de
Avalia??o do Ciclo de Vida (ACV) para realizar o estudo de compara??o do
desempenho ambiental entre o uso de GNV e Diesel-B5, considerando todas as
etapas desde a produ??o at? o consumo final dos combust?veis. Os resultados
mostraram que o maior potencial para aquecimento global (segundo o m?todo
IPCC) ocorre para o GNV, considerando per?odos de 20 anos, 100 anos e 500 anos.
Quando comparadas as contribui??es das diferentes etapas do processo, desde a
produ??o at? o uso do combust?vel, observou-se que o GNV apresenta os maiores impactos nas etapas de transporte e coleta de res?duos, enquanto o Diesel-B5
apresenta impacto significativo apenas na etapa de coleta de res?duos.
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Vehicle thermal management control systems / Systèmes de contrôle pour la gestion thermique d'un vehiculeSermeno Mena, Salvador 16 June 2015 (has links)
Les systèmes de refroidissement des véhicules continuent à se développer et devenir de plus en plus complexes. Ceci introduit des nouveaux problèmes dus aux interactions des composants et les perturbations du système. Avec la montée des prix des carburants; les développeurs et les compagnies cherchent à améliorer la consommation en respectant les normes d’émission. Une partie de l’énergie produite par le moteur est utilisé par les composants du circuit de refroidissement. L’utilisation d’auxiliaires électriques est une manière de réduire ces pertes parasites, mais ce n’est pas la seule solution. Des études récents proposent que un control plus adaptes des composants peux réduire la consommation de carburant. Actuellement, le groupe Volvo en essayant d’améliorer la performance du système de refroidissement des camions a installe des nouveaux composants pour la gestion thermique du moteur. Néanmoins, des problèmes ont été identifie lors d’essais véhicule. Une meilleure compréhension du système et de l’implémentation de composants est nécessaire pour limiter les effets non voulus. Le système de refroidissement d’un poids lourd a été étudié grâce à l’outil Bond Graph. Puis des nouvelles stratégies de control sont introduites : commande prédictive, commande par platitude, commande sans model et commande avec model réduit. Ces méthodes ont été implémentées dans une plateforme de simulation sur Matlab/Simulink. Les gains de consommation obtenue à partir de simulations sont entre 0.5 et 0.9%. Une analyse structurelle de l’architecture actuelle est présentée. D’après les conclusions de cette analyse, des propositions pour la modification de l’architecture du circuit sont évalués. / The increasing complexity of engine cooling systems results in added interactions and disturbances to the performance. Besides, non-propulsion loads (fan, water pump…) draw a significant percentage of the engine’s power thus lowering the vehicle’s fuel efficiency. Recent studies have shown that by controlling components the efficiency can be improved by adjusting fan speed according to cooling needs, coolant flow, and oil flow. Currently, the Volvo group in order to optimize the performance of their truck’s cooling systems had installed new thermal management components. However, problems were found while testing control strategies and a better understanding of the interaction between components is required to prevent this from happening again. In this work, the bond graph approach has been applied for the study of the cooling system of a Heavy duty vehicle and has enabled subsystem interactions to be identified. Based on a simplified model issued from the bond graph, several control strategies have been built. These controllers are based on different control approaches: model predictive control, flatness control, model free control and model free control with reduced order model. These controllers were implemented in a simulation platform in the Matlab/Simulink environment. Results of the implementation of the new advanced control strategies are given. Fuel economy gains ranged between 0.5 and 0.9 %. A structural analysis of the current architecture is also proposed aiming at the optimization of the system. Given the insights from the analysis, an assessment of new concepts for the cooling system architecture is proposed.
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The operational and safety effects of heavy duty vehicles platooningAlzahrani, Ahmed 01 January 2019 (has links)
Abstract
Although researchers have studied the effects of platooning, most of the work done so far has focused on fuel consumption. There are a few studies that have targeted the impact of platooning on the highway operations and safety. This thesis focuses on the impact of heavy-duty vehicles (HDVs) platooning on highway characteristics. Specifically, this study aims at evaluating the effects of platooning of HDVs on capacity, safety, and CO2 emissions.
This study is based on a hypothetical model that was created using the VISSIM software. VISSIM is a powerful simulation software designed to mimic the field traffic flow conditions. For model validity, the model outputs were compared with recommended values from guidelines such as the Highway Capacity Manual (HCM) (Transportation Research Board, 2016).
VISSIM was used to obtain the simulation results regarding capacity. However, in addition to VISSIM, two other software packages were used to obtain outputs that cannot be assessed in VISSIM. MOVES and SSAM are two simulation software packages that were used for emission and safety metrics, respectively. Both software packages depended on input from VISSIM for analysis.
It was found that with the presence of HDVs in the model, the capacity, the emission of CO2, and the safety of the roadway would improve positively. A capacity of 4200 PCE/h/ln could be achieved when there are enough HDVs in platoons. Furthermore, more than 3% of the traffic flow emission of CO2 reduction is possible when 100% of the HDVs used in the model are in platoons. In addition to that, a reduction of more than 75% of the total number of conflicts might be obtained.
Furthermore, with the analysis of the full factorial method and the Design of Experiment (DOE) conducted by using Excel and Minitab respectively, it was possible to investigate the impact of the platoons’ factors on the highway parameters. Most of these factors affect the parameters significantly. However, the change in the desired speed was found to insignificantly affect the highway parameters, due to the high penetration rate.
Keywords: VISSIM, MOVES, SSAM, COM-interface, HDVs, Platooning, Number of Conflicts
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Indicators and predictors of sleepinessvan den Berg, Johannes January 2006 (has links)
Sleep is a basic need as important as physical fitness and good nutrition. Without enough sleep, we will create a sleep debt and experience sleepiness. Sleepiness can be defined as the inability to stay awake, a condition that has become a health problem in our 24-hour-7-day-a-week society. Estimates suggest that up to one-third of the population suffers from excessive sleepiness. Among other interactions, sleepiness affects our performance, increasing the risk of being involved in accidents. A considerable portion of work related accidents and injuries are related to sleepiness resulting in large costs for the individuals and society. Professional drivers are one example of workers who are at risk of sleepiness related accidents. Up to 40% of heavy truck accidents could be related to sleepiness. A better knowledge about reliable indicators and predictors of sleepiness is important in preventing sleepiness related accidents. This thesis investigates both objective and subjective indicators of sleepiness, how these relate to each other, and how their pattern changes over time. The indicators investigated were electroencephalography, heart rate variability, simple reaction time, head movement, and subjective ratings of sleepiness (Study I-IV). In Study V, a questionnaire study was conducted with professional drivers in northern Sweden. This study mainly deals with predictors of sleepiness. When subjects were sleep deprived both objective and subjective ratings indicated a rapid increase in sleepiness during the first hour of the test followed by a levelling off. This change in pattern was evident for all the indicators except heart rate and heart rate variability. On the other hand, HRV was correlated with the increase of EEG parameters during the post-test sleep period. The changes in pattern of the indicators included in the thesis are analysed in the perspective of temporal patterns and relationships. Of the tested indicators, a subjective rating of sleepiness with CR-10 was considered to be the most reliable indicator of sleepiness. Of the investigated predictors of sleepiness, prior sleep habits were found to be strongly associated to sleepiness and the sleepiness related symptoms while driving. The influences of driving conditions and individual characteristics on sleepiness while driving were lower. A multidisciplinary approach when investigating and implementing indicators and predictors of sleepiness is important. In addition to their actual relations to the development of sleepiness, factors such as technical and practical limitations, work, and individual and situational needs must be taken into account.
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Rapid Exchange Solution (RES) : En mekanisk omlastningslösning för horisontell överföring av containrar mellan olika transportmedel / Rapid Exchange Solution (RES) : A mechanical solution for horizontal transferring of containers between different means of transportationBovin, Jimmy January 2013 (has links)
Detta examensarbete genomfördes våren 2013 på Karlstads universitet där TD Rail & Industry i Västerås stod som uppdragsgivare. Projektet innefattade att kartlägga nuvarande omlastningslösningar av enhetslaster mellan järnvägstransporter och vägtransporter, och utarbeta en konceptuell omlastningslösning med fokus på att öka järnvägstransporternas flexibilitet gentemot vägtransporterna. Där vikten lades på att utarbeta ett välarbetat helhetskoncept. Projektet genomfördes med designprocessen som grund och innehöll bland annat momenten; förstudie, kravspecificering, idégenerering, konceptval m.m. Resultatet blev en vidareutveckling av det redan befintliga systemet CCT som bygger på horisontell överföringsteknik och möjliggör därför omlastning av enhetslaster direkt under kontaktledning. Skillnaden mellan RES och CCT är att man tagit bort ombyggnationen av tågvagn och lastbilschassi, som var en av CCTs stora svagheter, genom två hydrauliska ”teknikplattor”. Tack vare detta tillsammans med sin låga investeringskostnad/driftkostnad öppnar RES nya möjligheter för omlastning på fler strategiska punkter direkt utmed järnvägsnätet och därmed ökar järnvägstransporternas flexibilitet. Som vidareutveckling av RES föreslås ett samarbete med CCT där man initialt utför mer detaljerade beräkningar på teknikplattorna. / This Bachelor of Science thesis was carried out in spring 2013 at Karlstad University for a company called TD Rail and Industry placed in Västerås, Sweden. The project included mapping of current transferring solutions of unit loads between railway and road transports, and the development of a conceptual transferring solution with the focus to increase the flexibility of the railway transport. The importance was to develop a well-made overall concept rather than small detailed parts of it. The project followed the design process methodology and included parts like: pre-study, requirements specification, idea generation, concept selection etc.The result was a further development of an already existing system called CCT based on horizontal transferring technology and therefore allow transferring of units directly under the overhead contact line. Thanks to this, together with its low investment / operating costs RES opens new opportunities for additional strategic transferring places along the railway, thereby increasing the flexibility of rail transports. The difference between RES and CCT is that you no longer need to rebuild the railway cars or the truckchassis , which was one of CCTs major weaknesses, instead the lifting mechanism is replaced by two hydraulic "technique plates". As a further development of the RES a partnership with CCT is proposed.
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Dynamic Decision Support for Regional LTL CarriersWarier, Prashant 18 May 2007 (has links)
This thesis focuses on decision support for regional LTL carriers. The basic operating characteristics of regional LTL carriers are similar to those of national LTL carriers, i.e., they operate linehaul networks with satellites, breakbulks, and relays to consolidate freight so as to be able to cost-effectively serve their customers. However, there are also key differences. Most importantly, because the area covered by a regional carrier is smaller, a regional carrier handles less freight (sometimes significantly less) and therefore typically has fewer consolidation opportunities, which results in higher handling and transportation costs per unit of freight. Consequently, competing with national carriers on price is difficult. Therefore, to gain or maintain market share, regional carriers have to provide better service. To be able to provide better service, regional carriers have to be more dynamic, e.g., they have to be able to deviate from their load plan when appropriate, which creates challenges for decision makers.
Regional carriers deliver about 60% of their shipments within a day and almost all of their shipments within two days. Furthermore, most drivers get back to their domicile at the end of each day. Therefore, the focus of the thesis is the development of effective and efficient decision models supporting daily operations of regional LTL carriers which provide excellent service at low cost.
This thesis presents an effective solution approach based on two optimization models: a dynamic load planning model and a driver assignment model. The dynamic load planning model consists of two parts: an integer program to generate the best paths for daily origin-destination freight volumes and an integer program to pack freight into trailers and trailers into loads, and to determine dispatch times for these loads. Techniques to efficiently solve these integer program solution are discussed in detail. The driver assignment model is solved in multiple stages, each stage requiring the solution of a set packing models in which columns represent driver duties. Each stages determines admissible driver duties. The quality and efficiency of the solution approach are demonstrated through a computational study with real-life data from one of the largest regional LTL carriers in the country.
An important "technique" for reducing driver requirements is the use of meet-and-turn operations. A basic meet-and-turn operation involves two drivers meeting at a location in between terminals and exchange trucks. A parking lot or a rest area suffices as a meet-and-turn location. This ensures that drivers return to the terminal where they started. More sophisticated meet-and-turn operations also exist, often called drop and hook operations. In this case, drivers do not exchange trucks, but one of their trailers. The motivation in this case is not to get drivers back to their domicile, but to reduce load-
miles. The thesis presents analytical results quantifying the maximum benefits of using meet and turn operations and optimization techniques for identifying profitable meet-and-turn opportunities.
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Schließringbolzen ohne Sollbruchstelle für wartungsfreie Verbindungen im Nutzfahrzeug- und StahlbauStädler, Hans-Albert 05 November 2012 (has links) (PDF)
Die Auswahl einer zweckmäßigen Verbindungstechnik hat großen Einfluss auf die Kosten für die Herstellung und Wartung von Gütern. Das mechanische Verbinden von Bauteilen mit Schließringbolzen gehört zum umformtechnischen Fügen. Damit werden kostengünstig unlösbare und mechanisch hoch beanspruchbare, punktförmige Verbindungen erzeugt.
Die vorliegende Arbeit hatte das Ziel, in umfassender Form den Nachweis zu erbringen, dass mit Schließringbolzensystemen ohne Sollbruchstelle wartungsfreie Verbindungen hergestellt werden können. Diese Wartungsfreiheit bezieht sich auf den Erhalt der mechanischen Eigenschaften der Verbindung und des Korrosionsschutzes bis zur beabsichtigten Grenznutzungsdauer. Aus einer Analyse des Standes der Technik wurde der Forschungsbedarf hinsichtlich der Wartungsfreiheit von Schließringbolzenverbindungen aus mechanischer und korrosiver Sicht abgeleitet. In einem mehrstufigen Prüfprogramm, unterteilt nach Anwendungen im Nutzfahrzeugbau und Stahlbau, wurde nach maschinenbaulichen und stahlbaulichen Konzepten die mechanische Leistungsfähigkeit der Verbindungen untersucht. Die Forschungsergebnisse aus diesem Programm und der Test neu entwickelter Beschichtungssysteme für die Bolzen und die Schließringe bestätigten die Eingangsthese über die Wartungsfreiheit. Metallografische Analysen und FEM Rechnungen ergänzen die Arbeit. Sie ist in sechs Abschnitte unterteilt und enthält 135 Abbildungen, 25 Tabellen, 3 Anlagen. Es wurden 118 Literaturquellen berücksichtigt. Mit der Arbeit steht dem Ingenieur ein umfangreiches Auskunftsmaterial zum Vergleich von Schließringbolzenverbindungen mit anderen Fügeverfahren, besonders jedoch zur Verschraubung zur Verfügung. Die durchgeführten Untersuchungen und Aussagen sollten in zukünftiger Forschung zu einem ganzheitlichen Konzept für die rechnerische Auslegung und Dimensionierung von Schließringbolzenverbindungen nach dem Vorbild der VDI 2230 und der EN 1993 weitergeführt werden.
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