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Mabbott, Nicholas. "Monitoring device for early warning signs of operator fatigue in open cut mines /". Access via Murdoch University Digital Theses Project, 2006. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20060809.93310.
Testo completo
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Douglas, Matthew Aaron Swartz Stephen M. "Commercial motor vehicle driver safety an application of ethics theory /". [Denton, Tex.] : University of North Texas, 2009. http://digital.library.unt.edu/permalink/meta-dc-11048.
Testo completo
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Desai, Anup. "Obstructive sleep apnoea and driver performance prevalence, correlates, and implications for driver fatigue /". Connect to full text, 2002. http://hdl.handle.net/2123/589.
Testo completoAbstract (sommario):
Thesis (Ph. D.)--University of Sydney, 2003.Includes tables and questionnaires. Title from title screen (viewed Apr. 29, 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the Faculty of Medicine. Degree awarded 2003; thesis submitted 2002. Includes bibliography. Also available in print form.
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Mohamedshah, Yusuf M. "Correlation of truck accidents with highway geometry /". This resource online, 1991. http://scholar.lib.vt.edu/theses/available/etd-10222009-125005/.
Testo completo
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Isaksson, Palmqvist Mia. "Model Predictive Control for Autonomous Driving of a Truck". Thesis, KTH, Skolan för elektro- och systemteknik (EES), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-187668.
Testo completoAbstract (sommario):
Platooning and cooperative driving can decrease the emissions of greenhouse gases and increase the traffic capacity of the roads. The Grand Cooperative Driving Challenge, GCDC, is a competition that will be held in May 2016 focusing on cooperative driving. A cornerstone in the cooperative driving is autonomous driving. The main objective of this thesis is to design a Model Predictive Control for a truck so it autonomously can perform the following tasks: follow a straight road, make a lane change and make a turn. Constraints are added to the vehicle states and the control signals. Additionally, a constraint is added to make the vehicle keep a safe distance to preceding vehicles. A Linear Time-Varying (LTV) MPC for reference tracking is derived. To use the MPC for reference tracking references for all the states and control signals are derived. For the lane change and turn scenario Bezier curves are used to obtain the position references. The controller is implemented in MATLAB and validated through simulations. For the simulations both a bicycle model of the vehicle and a more complicated four wheel model are used. The latter is implemented in Simulink. The bicycle model is on-line linearised around the references in order to be used as the prediction model for the LTV-MPC. The simulations show that the controller can make the vehicle perform the above mentioned tasks. With a horizon of 18 the time in average to perform one iteration of the control loop is 0.02 s. The maximum deviation in the lateral direction is 0.10 m and occurs for the turn scenario when the four wheel model is used for the simulations. Simulations are also done with a preceding vehicle. The controller is able to make the vehicle keep a safe distance to the preceding vehicle. If the preceding vehicle is driving slower than the controlled vehicle the controller is able to decrease the velocity of the controlled vehicle. In addition to the above mentioned, simulations are also done where disturbances and noise, separately, are added. As a disturbance an error in the start position is used. The vehicle can start 1.3 m from the real start position, in the lateral direction, and still find its way back to the trajectory. The noise is added as white noise to the position updates. The controller can deal with noise with a standard deviation up to 0.3 m.Kolonnkörning och kooperativkörning kan minska utsläppen av växthusgaser och öka trafikkapaciteten på vägarna. The Grand Cooperative Driving Challenge, GCDC, är en tävling med fokus på kooper-ativkörning som kommer att hållas i maj 2016. En hörnsten i kooperativkörning är autonomkörning. Det huvudsakliga målet med det här examensarbetet ¨ar att designa en MPC för en lastbil så att den autonomt kan genomföra följande: följa en rak väg, göra ett filbyte samt göra en sväng. Begränsningar är lagda på fordonets tillstånd och kontrollsignalerna. Utöver det begränsas avståndetet till framförvarande fordon. En linjär tidsvariant (LTV) MPC för referensföljning tas fram. För att använda MPC:n för referensföljning härleds referenser för fordonets tillstånd och kontrollsignaler. För filbytet och svängen används Bezier kurvor för att få fram positionsreferenserna. Regulatorn implementeras i MATLAB och valideras genom simuleringar. För simuleringarna används både en cykelmodell av fordonet och en mer komplicerad fyrhjuls-modell. Den senare implementeras i Simulink. Cykelmodellen linjäriseras online kring referenserna i syfte att användas som prediktionsmodell för LTV-MPC. Simuleringarna visar att regulatorn kan få fordonet att genomföra de ovan nämnda uppgifterna. Med en horisont på 18 ¨ar tiden det tar att genomföra en iteration av regulator-loopen i genomsnitt 0.02 sekunder. Den maximala avvikelsen i den laterala riktningen ¨ar 0.10 meter och uppstår när simuleringar görs för en sväng med fyrhjuls-modellen som fordonsmodell. Simuleringar görs även med ett framförvarande fordon. Regulatorn kan få fordonet att hallå ett säkerhetsavstånd till fordonet framför. Regulatorn kan vidare få fordonet att sänka hastigheten om det framförvarande fordonet kör långsammare. Utöver de ovan nämnda simuleringarna görs simuleringar där störningar och brus, var för sig, introduceras. Som störning används ett fel i startpositionen. Fordonet kan starta 1.3 meter från den korrekta startpositionen, i den laterala riktningen, och hitta tillbaks till referensbanan. Bruset adderas som vitt brus på positionsuppdateringarna. Regulatorn kan hantera vitt brus med en stan-dardavvikelse på upp till 0.3 meter.
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Mancino, Francesco. "An embedded model predictive controller for optimal truck driving". Thesis, KTH, Reglerteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-205649.
Testo completoAbstract (sommario):
An embedded model predictive controller for velocity control of trucks is developed and tested. By using a simple model of a heavy duty vehicle and knowledge about the slope of the road ahead, the fuel consumption while traveling near a set speed is diminished by almost 1% on an example road compared to a rule based speed control system. The problem is formulated as a look-ahead optimization problem were fuel consumption and total trip time have to be minimized. To find the optimal solution dynamic programming is used, and the whole code is designed to run on a Scania gearbox ECU in parallel with all the current software. Simulations were executed in a Simulink environment, and two test rides were performed on the E4 motorway.En algoritm för hastighetsstyrning baserad på modell-prediktiv reglering har utvecklats och testats på befintlig styrsystem i ett Scania lastbil. Genom att använda en enkel modell av fordonet och kunskap om lutningen på vägen framför den kunde man sänka bränsleförbrukningen med nästan 1% i vissa sträckor, jämfört med en regelbaserad farthållare. Problemet är formulerat som en optimerings-problem där bränsleförbrukning och total restid måste minimeras. För att hitta den optimala lösningen användes dynamisk programmering och hela koden är skriven så att den kan exekveras på en Scania styrenehet. Koden är kan köras parallellt med den mjukvara som är installerad på styrenheten. Simuleringar utfördes i en miljö utvecklad i Simulink. Två test-körningar på E4 motorvägen utfördes.
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Chan, Sau Yin. "Cross-border truck driving : negotiating work control and gendering work identity /". View Abstract or Full-Text, 2003. http://library.ust.hk/cgi/db/thesis.pl?SOSC%202003%20CHAN.
Testo completoAbstract (sommario):
Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2003.Includes bibliographical references (leaves 95-104). Also available in electronic version. Access restricted to campus users.
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Tanner, Deborah Brae. "No margin for error driving the east shore of Flathead Lake /". Diss., [Missoula, Mont.] : The University of Montana, 2009. http://etd.lib.umt.edu/theses/available/etd-12302009-133705.
Testo completo
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Mohamedshah, Yusaf M. "Correlation of truck accidents with highway geometry". Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/45243.
Testo completoAbstract (sommario):
Growth trends in vehicle transportation for the year 1989 showed that truck travel has increased from 400 billion vehicle miles of travel to 600 billion vehicle miles from 1980 to 1989, a staggering 50% increase. If this trend continues, then truck travel will reach 800 billion vehicle miles by the end of the year 2000. This increase in truck travel poses operational and safety problems for both passenger vehicles and trucks. To improve the existing highway facilities for trucks as well as to determine the design standards for new truck facilities, an understanding of the relationship between truck accidents and highway geometry is required. A number of models have been developed in the past but none of them consider all of the geometric features of the highway which are crucial for truck travel and the causation of truck accidents.
The objectives of this study were to identify the roadway variables that affect truck accidents and to develop mathematical models which would determine truck involvement rates, per mile, per year.
Data from the Highway Safety Information System (HSIS) was used in this analysis. The HSIS is a new data base developed by FHWA which contains accident, roadway and traffic data from five States. Models for truck accidents on Interstates, 2 lane rural roads, and for over turning accidents on Interstates were developed. The models indicate that truck accidents are primarily affected by horizontal curvature and vertical gradient albeit their values are different for Interstates and 2 lane rural roads. The number of truck accidents decreases on 2 lane rural roads as the shoulder width increases, and the model indicates that gradient has no effect on truck accidents on these roads and this, may be due to the inadequacy of the data. The Interstate model indicates that the higher the degree of curvature and the percentage of gradient, the greater the number of truck accident, as well as overturning truck accident involvement rates.Master of Science
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Anibas, Judith. "A study of virtual simulation in a truck driver training program". Online version, 2008. http://www.uwstout.edu/lib/thesis/2008/2008anibasj.pdf.
Testo completoAbstract (sommario):
Thesis PlanB (M.S.)--University of Wisconsin--Stout, 2008.ONLINE VERSION INCOMPLETE: APPENDIX A, P. 51; APPENDIX B, P. 52; APPENDIX I, P. 59; & APPENDIS J, P. 6 MISSING. Includes bibliographical references.
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Sallander, Cari. "Evaluation of a class A commercial truck drivers training program at the Eagle Company". Menomonie, WI : University of Wisconsin--Stout, 2007. http://www.uwstout.edu/lib/thesis/2007/2007sallanderc.pdf.
Testo completo
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Svensson, Martin. "Improved truck engine control for crane driving : - Focusing on fuel consumption". Thesis, KTH, Maskinkonstruktion (Inst.), 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-100223.
Testo completoAbstract (sommario):
Due to increased demands on fuel economy the question of a more intelligent engine control for driving a truck-mounted crane has been raised. The aim of this thesis is to develop a new engine control for crane driving. The primary concern for the new engine control is fuel economy, but other factors, such as driver environment and drivability, have been taken into consideration as well. A literature study investigating engine control in construction machines has also been carried out and the results are presented in this report. Due to the fact that the hydraulic control system as well as the diesel engine control system is designed by the same construction machine manufacturer, more complex control strategies are utilized in these applications. In order to test the new control strategy a full-scale test has been carried out on a Scania truck with a crane from Hiab. The results point towards lower fuel consumption, better driver experience and lower noise levels. Some of the control features of the new control are suggested to be placed in the crane, and some in the truck. Only a small expansion of the communication between truck and crane would be necessary in order for the new control strategy to work. The experiences from the literature study point on several features utilized in construction machines that could be implemented in the crane control of the future.På grund av ökade krav på minskad bränsleförbrukning har frågan om en förbättrad motorstyrning vid krankörning av lastbilsmonterade kranar blivit aktuell. Målet för detta examensarbete är att utveckla en ny motorstyrning anpassad för krankörning. I första hand syftar den nya motorstyrningen till att minska bränsleförbrukningen, men även andra faktorer såsom förarmiljö och körbarhet har tagits hänsyn till. En litteraturstudie om motorstyrning i hydrauliska grävmaskiner och andra hydrauliska maskiner har också utförts och resultatet finns presenterat i denna rapport. Eftersom det hydrauliska styrsystemet såväl som dieselmotorstyrsystemet är sammansatt hos en och samma tillverkare används mer komplicerade styralgoritmer i dessa tillämpningar. För att testa den nyutvecklade motorstyrningen har fullskaletest utförts på en Scanialastbil utrustad med en kran från Hiab. Resultaten pekar på lägre bränsleförbrukning, bättre förarupplevelse och lägre ljudnivå. Somliga av funktionerna i den nya styrningen föreslås placeras i lastbilen och andra i kranen. Bara en mycket liten utvidgning av kommunikationen mellan kran och lastbil skulle behövas för att denna styralgoritm skulle fungera. Lärdomarna ifrån litteraturstudien visar på att flera av de styrfunktioner som används ibland annat grävskopor skulle kunna komma till nytta i motor- och kran styrningen i en lastbilsmonterad kran i framtiden.
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McKinnon, Peter Laurence, University of Western Sydney, College of Social and Health Sciences e of Nursing Family and Community Health School. "Tired of dying : fatigue and stress in long distance road transport". THESIS_CSHS_NFC_McKinnon_P.xml, 2004. http://handle.uws.edu.au:8081/1959.7/657.
Testo completoAbstract (sommario):
In this thesis, the author has drawn on a large body of international research and his own surveys, interviews and experience to examine the interrelated issues of Fatigue and Stress in the long distance sector of the Australian road transport industry. Two major Australian studies are studied in some detail: House of Representatives Standing Committee on Communications, Transport and the Arts: Beyond the Midnight Oil, Report into an Inquiry into Managing Fatigue in Transport, Parliament of the Commonwealth of Australia October 2000 (The Neville Report) and Quinlan, Michael, Report of an Inquiry into Safety in the Long Haul Sector of the Road Trucking Industry, Motor Accident Authority of NSW, Nov 2001 and the United States of America: Belzer, Michael H., Sweatshop on Wheels: Winners and Losers in Trucking Deregulation, Oxford University Press, New York, 2000, has direct relevance to this study, especially as it relates to the underlying causes of much of the fatigue and stress suffered by long distance drivers. An extensive literature review was undertaken to help form an understanding of the issues and developments relating to workplace fatigue and stress, in several different settings, including the military, aviation and general industry. The author has surveyed a number of long distance drivers and interviewed managers and others linked to this industry, analysed their responses and reported on the findings. Since the commencement of this study, several significant changes have occurred in the relevant legislation and its application, and where possible these have been incorporated into the studyMaster of Science (Hons)
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Evans, Timothy L. "A study to determine the correlation between the length of formalized training and the driving/safety records of commercial truck drivers". Online version, 2001. http://www.uwstout.edu/lib/thesis/2002/2002evanst.pdf.
Testo completo
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Douglas, Matthew Aaron. "Commercial Motor Vehicle Driver Safety: An Application of Ethics Theory". Thesis, University of North Texas, 2009. https://digital.library.unt.edu/ark:/67531/metadc11048/.
Testo completoAbstract (sommario):
Safety is an important aspect of ethical, socially responsible logistics. Current U.S. motor carrier (MC) safety research topical coverage includes the effects of individual and environmental influences, carrier safety management, and regulatory compliance on carrier safety and driver fatigue/safety performance. Interestingly, little research on the subject of truck drivers' safety attitudes and behaviors exists and the underlying decision-making processes that guide drivers' safety-related behaviors have received little attention. Furthermore, researchers have not provided an integrated framework that explains individual, organizational, and regulatory factors' impact on drivers' safety decision-making and performance. Truck drivers' safety judgments, decisions, and actions must adhere to societal safety norms. To that end, ethical decision-making theory that draws from the deontological and teleological traditions in moral philosophy provides a theoretical foundation and integrated framework necessary to better understand drivers' safety decision-making processes. The current research sought to determine how drivers rely on safety norms and perceived consequences in forming safety judgments and behavioral intentions. Furthermore, the study was designed to explore how various factors (i.e., individual, organizational, and regulatory) influence drivers' safety decision-making processes. Specifically, the study sought to answer the broad question, "How do commercial motor vehicle drivers make safety-related decisions, and how do individual, organizational, and regulatory factors influence drivers' safety decision-making processes?" An experimental two-factor design (2×2) was used to manipulate safety norms (i.e., "deontologically unsafe situation" and "deontologically safe situation") and consequences (i.e., "positive consequences" and "negative consequences"). Multivariate statistical analysis revealed that drivers primarily rely on deontological evaluations in forming safety judgments. Furthermore, drivers primarily relied on safety judgments when forming behavioral intentions. Drivers' attitudes toward unsafe actions and the effectiveness of driver-related safety regulations were also influential to drivers' judgments and intentions, respectively. The empirical findings demonstrate to managers that communication and education of safety norms may be highly effective to improve safety in unique occupational contexts where employees are given high levels of responsibility with little physical supervision, and where judgment errors can have devastating consequences for multiple stakeholders.
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Riley, Kevin William. "Governing speed amphetamine use among truck drivers and the making of deviance /". Diss., Restricted to subscribing institutions, 2009. http://proquest.umi.com/pqdweb?did=1998392191&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.
Testo completo
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Higgs, Bryan James. "Application of Naturalistic Truck Driving Data to Analyze and Improve Car Following Models". Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/36089.
Testo completoAbstract (sommario):
This research effort aims to compare car-following models when the models are calibrated to individual drivers with the naturalistic data. The models used are the GHR, Gipps, Intelligent Driver, Velocity Difference, Wiedemann, and the Fritzsche model. This research effort also analyzes the Wiedemann car-following model using car-following periods that occur at different speeds. The Wiedemann car-following model uses thresholds to define the different regimes in car following. Some of these thresholds use a speed parameter, but others rely solely upon the difference in speed between the subject vehicle and the lead vehicle. This research effort also reconstructs the Wiedemann car-following model for truck driver behavior using the Naturalistic Truck Driving Studyâ s (NTDS) conducted by Virginia Tech Transportation Institute. This Naturalistic data was collected by equipping 9 trucks with various sensors and a data acquisition system. This research effort also combines the Wiedemann car-following model with the GHR car-following model for trucks using The Naturalistic Truck Driving Studyâ s (NTDS) data.Master of Science
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Lima, Pedro. "Predictive control for autonomous driving : With experimental evaluation on a heavy-duty construction truck". Licentiate thesis, KTH, Reglerteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-186123.
Testo completoAbstract (sommario):
Autonomous vehicles is a rapidly expanding field, and promise to play an important role in society. In more isolated environments, vehicle automation can bring significant efficiency and production benefits and it eliminates repetitive jobs that can lead to inattention and accidents. The thesis addresses the problem of lateral and longitudinal dynamics control of autonomous ground vehicles with the purpose of accurate and smooth path following. Clothoids are used in the design of optimal predictive controllers aimed at minimizing the lateral forces and jerks in the vehicle. First, a clothoid-based path sparsification algorithm is proposed to efficiently describe the reference path. This approach relies on a sparseness regularization technique such that a minimal number of clothoids is used to describe the reference path. Second, a clothoid-based model predictive controller (MPCC) is proposed. This controller aims at producing a smooth driving by taking advantage of the clothoid properties. Third, we formulate the problem as an economic model predictive controller (EMPC). In EMPC the objective function contains an economic cost (here represented by comfort or smoothness), which is described by the second and first derivatives of the curvature. Fourth, the generation of feasible speed profiles, and the longitudinal vehicle control for following these, is studied. The speed profile generation is formulated as an optimization problem with two contradictory objectives: to drive as fast as possible while accelerating as little as possible. The longitudinal controller is formulated in a similar way, but in a receding horizon fashion. The experimental evaluation with the EMPC demonstrates its good performance, since the deviation from the path never exceeds 30 cm and in average is 6 cm. In simulation, the EMPC and the MPCC are compared with a pure-pursuit controller (PPC) and a standard MPC. The EMPC clearly outperforms the PPC in terms of path accuracy and the standard MPC in terms of driving smoothness.QC 20160503
iQMatic
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Toole, Laura Marie. "Crash Risk and Mobile Device Use Based on Fatigue and Drowsiness Factors in Truck Drivers". Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/47599.
Testo completoAbstract (sommario):
Driver distraction has become a major concern for the U.S. Department of Transportation (US DOT). Performance decrements are typically the result of driver distraction because attentional resources are limited, which are limited; fatigue and drowsiness limit attentional resources further. The purpose of the current research is to gain an understanding of the relationship between mobile device use (MDU), fatigue, through driving time and time on duty, and drowsiness, through time of day and amount of sleep, for commercial motor vehicle drivers. A re-analysis of naturalistic driving data was used to obtain information about the factors, MDU, safety-critical events (SCE), and normal driving epochs. Odds ratios were used to calculate SCE risk for 6 mobile device use subtasks and each of the factors, which were divided into smaller bins of hours for more specific information. A generalized linear mixed model and chi-square test were used to assess MDU for each factor and the associated bins. Results indicated visually demanding subtasks were associated with an increase in SCE risk, but conversation on a hands-free cell phone decreased SCE risk. There was an increase in SCE risk for visual manual subtasks for all bins in which analyses were possible. Drivers had a higher proportion of MDU in the early morning (circadian low period) than all other times of day that were analyzed. These results will be used to create recommended training and evaluate policy and technology and will help explain the relationship between MDU, fatigue, and drowsiness.Master of Science
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Toole, Laura. "Crash Risk and Mobile Device Use Based on Fatigue and Drowsiness Factors in Truck Drivers". Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/47599.
Testo completoAbstract (sommario):
Driver distraction has become a major concern for the U.S. Department of Transportation (US DOT). Performance decrements are typically the result of driver distraction because attentional resources are limited, which are limited; fatigue and drowsiness limit attentional resources further. The purpose of the current research is to gain an understanding of the relationship between mobile device use (MDU), fatigue, through driving time and time on duty, and drowsiness, through time of day and amount of sleep, for commercial motor vehicle drivers. A re-analysis of naturalistic driving data was used to obtain information about the factors, MDU, safety-critical events (SCE), and normal driving epochs. Odds ratios were used to calculate SCE risk for 6 mobile device use subtasks and each of the factors, which were divided into smaller bins of hours for more specific information. A generalized linear mixed model and chi-square test were used to assess MDU for each factor and the associated bins. Results indicated visually demanding subtasks were associated with an increase in SCE risk, but conversation on a hands-free cell phone decreased SCE risk. There was an increase in SCE risk for visual manual subtasks for all bins in which analyses were possible. Drivers had a higher proportion of MDU in the early morning (circadian low period) than all other times of day that were analyzed. These results will be used to create recommended training and evaluate policy and technology and will help explain the relationship between MDU, fatigue, and drowsiness.Master of Science
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ANDERSSON, OSCAR, e LUCAS MOLIN. "AutoTruck : Automated docking with internal sensors". Thesis, KTH, Mekatronik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-233142.
Testo completoAbstract (sommario):
The purpose of this bachelor thesis was to discover how an articulated vehicle can park itself using a pre-defined parking path with a combination of ultrasonic sensors as well as a rotary angle sensor. The project was divided into two parts: constructing a small scale demonstrator and the software controlling the demonstrator. The demonstrator was constructed from offthe- shelf components and custom parts. The truck was designed based on a rear wheel driven truck with Ackermann steering. The localization of a parking spot and measuring other distances was done with ultrasonic sensors and the hitch angle was measured by a rotary angle sensor. The performance of the demonstrator was evaluated by measuring the trailers angle difference from the center line of the parking spot. The performance was deemed to be reasonably good with successful parkings in 8 out of 10 attempts.Kandidatarbetet syftar till att undersöka hur ett ledat fordon kan parkera sig självt efter en förbestämd parkeringsrutt med en kombination av flera ultraljudssensorer samt en vinkelgivare. Projektet består av två delar; konstruktion av ett miniatyrfordon samt mjukvaran som styr fordonet. Fordonet tillverkades från butiksköpta komponenter och skräddarsydda delar. Lastbilens design var baserad på en bakhjulsdriven Ackermannstyrd lastbil. Identifieringen av en parkeringsplats samt avståndsmätning hanterades av ultraljudssensorer och hitch vinkeln mättes av en vinkelgivare. Miniatyrfordonets prestanda utvärderades genom att mäta släpets vinkelskillnad från centerlinjen av parkeringsplatsen. Prestandan ansågs att vara tillräckligt god med lyckade parkeringar i 8 av 10 tester.
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Kašparová, Hana. "Měření zpomalení nákladních automobilů do 12 tun při brzdění motorem". Master's thesis, Vysoké učení technické v Brně. Ústav soudního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-233050.
Testo completoAbstract (sommario):
This thesis deals with braking effect of the truck’s engine. The theoretical part introduces the reader to the basic construction of trucks, describes most using engine and defines the factors having a significant effect on engine braking. In the practical part the reader is familiar with the technique used in making the measurement and description of the vehicle chosen for the implementation of measurement. The result of the practical part is the values obtained by measurement including their interpretation contained in the conclusion.
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Johansson, Joel. "Why does a sleepy driver continue to drive?" Thesis, Department of computer and information science, Linköping University, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:vti:diva-596.
Testo completoAbstract (sommario):
Inom trafikforskningen är det allmänt känt att sömnighet är en starkt bidragande faktor vid trafikolyckor. Tidigare forskning har visat att sömnighet hos förare är närvarande i 16-23 procent av alla bilolyckor. Inom flyg- och järnvägsdomänen har en metod, med en stark influens från human factors-området, kallad Fatigue risk management (FRM) använts för att undersöka hur sociala och organisatoriska faktorer påverkar personalens sömnighetsnivå. Dock har denna metod inte använts för att undersöka lastbilsförares sömnighetsnivå i någon större utsträckning. Studiens syfte var att undersöka hur lastbilsförare upplever, motarbetar och motverkar sömnighet i deras dagliga arbetssituation. Resultaten visar att lastbilsförare i sitt arbete möter en stor mängd trötthetsbidragande faktorer, som kan härledas både till organisatoriska faktorer och individuellt beteende. Möjliga sätt att motverka sömnighet bland lastbilsförare, riktade mot både individen och organisationen, föreslås.In the traffic domain it is commonly known that sleepiness is a highly contributing factor in traffic accidents. Research has shown that sleepiness among drivers is present in about 16-23 per cent of all car accidents. In the aviation and railway industry a method or framework with some shared influences from the Human Factors approach, called Fatigue Risk Management (FRM) has been used to investigate how social and organisational factors affect the personnels level of sleepiness. The overall aims of this study are to investigate how truck drivers experience, fight and counteract sleepiness in their daily work environment. The results show that drivers face a wide variety of sleep contributing factors, stemming from both organisational factors and individual behaviour. Possible ways of counteracting truck driver sleepiness, concerning both the individual and the organisation, are also suggested.
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Fatollahzadeh, Kianoush. "A laboratory vehicle mock-up research work on truck driver’s selected seat position and posture : A mathematical model approach with respect to anthropometry, body landmark locations and discomfort". Doctoral thesis, KTH, Industriell ekonomi och organisation (Inst.), 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4028.
Testo completoAbstract (sommario):
Professional truck drivers are highly exposed to fatigue and work related injuries. Truck drivers are common victims of musculoskeletal disorders, frequently suffering from pain symptoms particularly in the neck, shoulder and lower back. This situation is believed to be a contributor to the high absenteeism in this job category. A high percentage of this problem is due to the adoption of an unhealthy driving posture resulting from inappropriate seat design. This incorrect and poor design is owing to the insufficient and obsolete anthropometrical data which has been used for decades for arranging and positioning components in the driver environment. The main objective of the present study was to create and construct a mathematical model which clarifies and predicts the drivers’ comfortable sitting posture and position. It was hypothesized that the length and height characteristics of some body segments as well as the body weight and waist circumference of the driver have a great impact on the selection of a specific sitting posture. The steering wheel positions as well as the pedal/floor locations were hypothesized to be highly correlated to the driver’s selected posture and the corresponding comfort. The effect of the seat position on posture selection and related comfort assessments constituted the other hypothesis of the study which received extra attention. A laboratory experiment on a Scania truck cab mock-up was conducted. The seat track travel along a vertical as well as horizontal forward-backward path was obtained by mounting the seat on the motorized rigid frame which allowed unrestricted vertical and fore-aft travel. The seat cushion angle and backrest angle were adjusted by pivoting the entire seat and backrest around a lateral axis and independently. The pedal components were mounted on a motorized platform, thus allowing unrestricted fore-aft and height travel without any changes in the pedal angles. The steering wheel was mounted on the instrument panel by two independent pneumatic axes which allowed a wide range of adjustments including tilting and moving along the sagittal plane for adjusting the height and distance. The test plan called for 55 international highly experienced heavy truck drivers. The drivers were recruited to span a large range of body weight and stature, in particular to ensure adequate representation of both the extreme as well as the normal group of drivers. The drivers filled in a general information questionnaire before undergoing the anthropometrical measurements and thereafter the test trials. The experiment contained a subset of test conditions with five different trials using random selection sampling procedure. Drivers were asked to adjust the components in a wide range of trajectory according to a written protocol. A sparse set of threedimensional body landmark locations and the corresponding comfort assessments were recorded. As the main part of the result, the mathematical models using multiple regression analyses on selected body landmarks as well as anthropometrical measures were developed which proposed a linear correlation between parameters. The differences between the observed data and the corresponding predicted data using the model were found to be minimal and almost dispensable. Additionally, the drivers preferred to sit in the rearmost position and at a rather high level relative to the rest of the available and adjustable area. Considering the normal adjustable seat area of the cab, only a very small part of the observed Hpoint data lies within this area while a large remaining amount of data lies outside of it. Moreover, the difference between the observation (plotted H-point data) and the neutral H-point was found to be significant. Furthermore, and since some of the data lies almost on the border of the adjustable area, it may indicate a reasonable tendency for even more seat adjustment in the backward direction. A conceptual model consisting of four different parameters was developed and presented in the end. These parameters of the model suggest being as key factors which play a central role on process of decision making regarding the selection of a desirable sitting posture. Any eventual modifications and adjustments for elimination or minimizing discrepancies, biases or obscured factors affecting the quality of the mathematical model would be a case for future study. The investigation of a complete assessment of comfort should be supplemented with an analysis of how many truck drivers are satisfied with the comfort in the end.QC 20100824
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Greenberg, David Brett. "Highway Religion: Truckstop Chapels, Evangelism, and Lived Religion on the Road". Oberlin College Honors Theses / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=oberlin1315764530.
Testo completo
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Van, Box Som Annick. "Des sciences humaines aux sciences de l’ingénieur : comportements humains, activités finalisées et conception de systèmes d’assistance à la conduite de véhicules industriels". Thesis, Lyon 2, 2010. http://www.theses.fr/2010LYO20105/document.
Testo completoAbstract (sommario):
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 urbainDriving 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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Jirásková, Iveta. "Vliv zatížení nákladních vozidel na jejich dosažitelné zpomalení". Master's thesis, Vysoké učení technické v Brně. Ústav soudního inženýrství, 2020. http://www.nusl.cz/ntk/nusl-433226.
Testo completoAbstract (sommario):
The diploma thesis deals with the issue of braking trucks at different loads. The theoretical part defines the basic construction of trucks, truck brakes, the braking process and the factors that affect braking, braking deceleration, and legislative requirements for truck brakes. The practical part describes the course of experimental measurements, the use of the technique, the place of measurement, atmospheric conditions and used trucks. At the end of the work, based on experimental measurements, the obtained values of braking deceleration of trucks are evaluated.
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Liu, Yi. "Time-Varying Coefficient Models for Recurrent Events". Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/97999.
Testo completoAbstract (sommario):
I have developed time-varying coefficient models for recurrent event data to evaluate the temporal profiles for recurrence rate and covariate effects. There are three major parts in this dissertation. The first two parts propose a mixed Poisson process model with gamma frailties for single type recurrent events. The third part proposes a Bayesian joint model based on multivariate log-normal frailties for multi-type recurrent events. In the first part, I propose an approach based on penalized B-splines to obtain smooth estimation for both time-varying coefficients and the log baseline intensity. An EM algorithm is developed for parameter estimation. One issue with this approach is that the estimating procedure is conditional on smoothing parameters, which have to be selected by cross-validation or optimizing certain performance criterion. The procedure can be computationally demanding with a large number of time-varying coefficients. To achieve objective estimation of smoothing parameters, I propose a mixed-model representation approach for penalized splines. Spline coefficients are treated as random effects and smoothing parameters are to be estimated as variance components. An EM algorithm embedded with penalized quasi-likelihood approximation is developed to estimate the model parameters. The third part proposes a Bayesian joint model with time-varying coefficients for multi-type recurrent events. Bayesian penalized splines are used to estimate time-varying coefficients and the log baseline intensity. One challenge in Bayesian penalized splines is that the smoothness of a spline fit is considerably sensitive to the subjective choice of hyperparameters. I establish a procedure to objectively determine the hyperparameters through a robust prior specification. A Markov chain Monte Carlo procedure based on Metropolis-adjusted Langevin algorithms is developed to sample from the high-dimensional distribution of spline coefficients. The procedure includes a joint sampling scheme to achieve better convergence and mixing properties. Simulation studies in the second and third part have confirmed satisfactory model performance in estimating time-varying coefficients under different curvature and event rate conditions. The models in the second and third part were applied to data from a commercial truck driver naturalistic driving study. The application results reveal that drivers with 7-hours-or-less sleep prior to a shift have a significantly higher intensity after 8 hours of on-duty driving and that their intensity remains higher after taking a break. In addition, the results also show drivers' self-selection on sleep time, total driving hours in a shift, and breaks. These applications provide crucial insight into the impact of sleep time on driving performance for commercial truck drivers and highlights the on-road safety implications of insufficient sleep and breaks while driving. This dissertation provides flexible and robust tools to evaluate the temporal profile of intensity for recurrent events.PHD
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Timur, Emre Robert, e Byggnings Lina Lindbom. "Managing transformation pressure in large organizations : A case study on a product development organization in the transport and truck industry". Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264097.
Testo completoAbstract (sommario):
Why do some large organizations succeed during transformations and others do not? This thesis aims to contribute and expand the discussion of how product development capabilities could enable success during transformations. To investigate the problem, a qualitative case study was performed at a large transport and truck incumbent, Scania CV AB. The transport and truck industry is currently pressured to transform, both from a competitive and sustainability perspective. In order to become more adaptable to change, the thesis identified the importance of clearly applying ambidexterity as a strategy to cope with challenges that the transformation implies. However, when applying ambidexterity, interface challenges between exploitation and exploration occur. Success during transformations is mainly dependent on the management to handle those interface challenges properly. This thesis identified two main managerial practices that could benefit incumbents in the transport and truck industry to become more adaptable during a transformation phase. Firstly, a clear strategy of how to manage innovations over time could support large incumbents to leverage innovations for optimal experimentation, scalability, and later profit. Secondly, clear organizational alignment between functions to enhance communication and prioritization especially between exploitative and explorative business activities could support large incumbents to leverage radical innovations within the organization. This thesis argues that implementing structural ambidexterity combined with a clear and streamlined innovation transfer process in three distinct horizons for mature, growth, and future businesses will increase adaptability during transformation pressure. As the main area of future research, this thesis proposes to further investigate the opportunities of an open innovation strategy that leverages partnerships for co-creation in an increasingly interconnected transport ecosystem.Hur kommer det sig att vissa företag lyckas under industriell förändring och andra inte? Syftet med denna uppsats är att bidra till, och utvidga, diskussionen om hur kapabiliteter inom produktutveckling kan främja en lyckad transformation. För att undersöka problemet genomfördes en kvalitativ fallstudie på ett etablerat företag inom transport och lastbilsindustrin, Scania CV AB. Transportindustrin är för närvarande under stor press, både från ett konkurrens- och hållbarhetsperspektiv. Denna studie visar att, för att bli mer adaptiv och hantera förändring, är det av yttersta vikt att implementera en tydlig strategi för en tvehänt (ambidextrous) organisation. En av de största utmaningarna vid en sådan implementation är dock de starka spänningar som uppstår i gränssnitten mellan det operationella och det utforskande inom organisationen. Hur de hanterar dessa utmaningar från ett ledarskapsperspektiv, kommer därav vara en av de främsta faktorerna till om företaget lyckas anpassa sig till förändring. I studien har två grundläggande principer för ledarskap identifierats, vilka kan hjälpa etablerade företag inom transport- och lastbilsindustrin att bli mer adaptiva under förändring. För det första, en tydlig strategi för att hantera innovation över tid, kan stötta ett etablerat företag att optimera innovation, skalbarhet och vinst. För det andra, en tydlig organisations- och ledarskapsinriktning som lyfter kommunikation och underlättar prioritering mellan förvaltande och utforskande aktiviteter och avdelningar. Denna studie argumenterar för strukturell separering av organisationen, kombinerat med en process för att överföra innovationer. Detta kan åstadkommas genom en uppdelning på tre horisonter; mognad, tillväxt och framtid, vilket kommer att öka företagets anpassningsförmåga under förändring. Denna studie har avgränsats till att inte närmare undersöka hur partnerskap kan hanteras i det allt mer sammankopplade transportsystemet. Detta är dock identifierat som ett möjligt behov av att närmare undersöka hur strategier för open innovation kan främja partnerskap och samproduktion inom området.
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Andersson, Oscar, e Lucas Molin. "AutoTruck : Automated docking with internal sensors". Thesis, KTH, Maskinkonstruktion (Inst.), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-230383.
Testo completoAbstract (sommario):
The purpose of this bachelor thesis was to discover howan articulated vehicle can park itself using a pre-definedparking path with a combination of ultrasonic sensors aswell as a rotary angle sensor.The project was divided into two parts: constructing asmall scale demonstrator and the software controlling thedemonstrator. The demonstrator was constructed from offthe-shelf components and custom parts. The truck was designedbased on a rear wheel driven truck with Ackermannsteering. The localization of a parking spot and measuringother distances was done with ultrasonic sensors and thehitch angle was measured by a rotary angle sensor.The performance of the demonstrator was evaluated bymeasuring the trailers angle difference from the center lineof the parking spot.The performance was deemed to be reasonably goodwith successful parkings in 8 out of 10 attempts.Kandidatarbetet syftar till att undersöka hur ett ledatfordon kan parkera sig självt efter en förbestämd parkeringsruttmed en kombination av flera ultraljudssensorersamt en vinkelgivare.Projektet består av två delar; konstruktion av ett miniatyrfordonsamt mjukvaran som styr fordonet. Fordonettillverkades från butiksköpta komponenter och skräddarsyddadelar. Lastbilens design var baserad p°a en bakhjulsdrivenAckermannstyrd lastbil. Identifieringen av en parkeringsplatssamt avståndsmätning hanterades av ultraljudssensoreroch hitch vinkeln mättes av en vinkelgivare.Miniatyrfordonets prestanda utvärderades genom attmäta släpets vinkelskillnad från centerlinjen av parkeringsplatsen.Prestandan ansågs att vara tillräckligt god med lyckadeparkeringar i 8 av 10 tester.
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Logofatu, Cristina. "Improving communication in a transportation company by using a Web page". CSUSB ScholarWorks, 2004. https://scholarworks.lib.csusb.edu/etd-project/2520.
Testo completoAbstract (sommario):
The Internet has become a very powerful tool in improving communication, making it easier, more convenient, and faster to access or exchange information. This project takes advantage of the strengths the Internet provides by improving communication by developing a web site for a transportation company.
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Oliveira, Daniela Barboza de. "A reestruturação produtiva e o trabalho dos motoristas de caminhão: um estudo de caso em duas empresas de transporte rodoviário de carga". Universidade Federal de São Carlos, 2012. https://repositorio.ufscar.br/handle/ufscar/3720.
Testo completoAbstract (sommario):
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Previous issue date: 2012-02-28Financiadora de Estudos e Projetos
The present study has for objective to identify effects of the productive reorganization in the work of truck drivers, in the period between 1980 and 1990 in Brazil. This research is a study of case about two companies of road haulage (RH), with tradition in the segment. They had been selected on the basis of the time of performance in the market, regions of operation and localization of the company. Following criteria defined previously, involving mainly the work time, drivers (salary earning and aggregate) and managers of different areas had been interviewed with a focus on trajectory of work within the company. Beyond the study of case, the bibliographical research on the history of the RH in Brazil contributed to understand the moment the road haulage becames predominant in the country and why. The results show that, historically, the road transport always was connected to the industrial sector and that the changes in the management of the production of this sector had direct impact in the management of the transports. Thus, since the 1990s, the transporters have increased the agility of the process of transport, reduced costs and time spent, guaranteeing the quality of the services given through the use of concepts and practices linked to Suplly Chain Management (SCM) and Logistics. New practices in an old labor model: new employment contracts to reduce costs and avoid the limitations of labor law (outsourcing), extension of working hours and remuneration for productivity (to drive more is to earn more). The absence of an adequate legislation that regulates the activities of the RH and imposes limits to the drive time and distinguishes it and the work time, equally contributes to the long labor journey to become one more factor of risk in this profession, especially between the drivers who work with fast orders lines.
O presente estudo tem por objetivo identificar os efeitos da reestruturação produtiva no trabalho dos motoristas de caminhão, no período compreendido entre os anos 1980 e 1990, no Brasil. Por meio do estudo de caso, duas empresas de transporte rodoviário de carga (TRC), com tradição nesse segmento, foram selecionadas com base no tempo de atuação no mercado, regiões atendidas e localização da matriz. Seguindo critérios previamente definidos, principalmente no que diz respeito ao tempo de trabalho, motoristas (assalariados e agregados) e gerentes de diferentes áreas foram entrevistados sobre a sua trajetória de trabalho no interior de cada empresa. Além do estudo de caso, a pesquisa bibliográfica sobre a história do TRC no Brasil contribuiu para entender em que momento o modal rodoviário tornou-se predominante no país e por quê. Os resultados mostram que, historicamente, o transporte rodoviário de carga sempre esteve atrelado ao setor industrial e que as mudanças na gestão da produção desse setor impactam diretamente na gestão dos transportes. Assim, desde os anos 1990, as transportadoras têm conseguido agilizar todo o processo de movimentação de cargas, bem como reduzir custos e prazos, garantindo a qualidade dos serviços prestados por meio dos conceitos e práticas do Suplly Chain Management (SCM) e da logística. São práticas novas em meio a um velho modelo trabalhista, que resultou em: terceirização da mão-de-obra como forma de driblar a legislação trabalhista e reduzir custos; contratos de trabalho que visam a remuneração com base na produtividade (quem dirige mais recebe mais) e jornada de trabalho prolongada. A ausência de uma legislação adequada que regulamente as atividades do TRC e que limite o tempo de direção e o diferencie do tempo de trabalho, igualmente contribui para que a organização do trabalho torne-se mais um fator de risco nessa profissão, especialmente entre os motoristas que atuam em linhas de encomendas rápidas.
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Rosenqvist, Rebecka, e Maria Wikström. "Individualisation of a Driver Coaching Service : Combining Design Ethnography and Service Design to Gain Insights About the Coaches’ Role and Activities". Thesis, Linköpings universitet, Institutionen för datavetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-149647.
Testo completoAbstract (sommario):
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.
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Jenkins, Jacqueline Marie. "Modeling the interaction between passenger cars and trucks". Texas A&M University, 2004. http://hdl.handle.net/1969.1/1296.
Testo completoAbstract (sommario):
The topic of this dissertation was the use of distributed computing to improve the modeling of the interaction between passenger cars and trucks. The two main focus areas were the development of a methodology to combine microscopic traffic simulation programs with driving simulator programs, and the application of a prototype distributed traffic simulation to study the impact of the length of an impeding vehicle on passing behavior.
The methodology was motivated by the need to provide an easier way to create calibrated traffic flows in driving simulations and to capture vehicle behavior within microscopic traffic simulations. The original design for the prototype was to establish a two-way, real time exchange of vehicle data, however problems were encountered that imposed limitations on its development and use.
The passing study was motivated by the possible changes in federal truck size and weight regulations and the current inconsistency between the passing sight distance criteria for the design of two lane highways and the marking of no-passing zones. Test drivers made passing maneuvers around impeding vehicles that differed in length and speed. The main effects of the impeding vehicle length were found to be significant for the time and distance in the left lane, and the start and end gap distances.
Passing equations were formulated based on the mechanics of the passing maneuver and included behavior variables for calibration. Through a sensitivity analysis, it was shown that increases in vehicle speeds, vehicle length, and gap distance increased the distance traveled in the left lane, while increases in the speed difference and speed gain decreased the distance traveled in the left lane. The passing equations were calibrated using the current AASHTO values and used to predict the impact of increased vehicle lengths on the time and distance in the left lane. The passing equations are valuable for evaluating passing sight distance criteria and observed passing behavior.
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van, den Berg Johannes. "Indicators and predictors of sleepiness". Doctoral thesis, Umeå : Public Health and Clinical Medicine, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-708.
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Neuweiler, Lukas, e Pia Vanessa Riedel. "Autonomous Driving in the Logistics Industry : A multi-perspective view on self-driving trucks, changesin competitive advantages and their implications". Thesis, Internationella Handelshögskolan, Högskolan i Jönköping, IHH, Centre of Logistics and Supply Chain Management (CeLS), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-36803.
Testo completoAbstract (sommario):
Background: Nowadays, logistics service providers face several challenges which create an urge to rethink their strategy to improve their position within the market,decrease their costs and their environmental impact. At the same time theintroduction of autonomous driving potentially has an impact on logistics.Self-driving trucks can help logistics companies to tackle these challenges.However, the implementation of this technology could fundamentally alterthe competitive landscape. Hence, certain competitive advantages currentlyheld by logistics firms might lose their relevance in the future and need tobe adapted to maintain a strong market position. Purpose: The purpose of this study is to explore the perception of self-driving trucks within logistics and the impact on competitive advantages of logistics service providers. Thereby, this thesis will look at experts from Germany and Sweden and their opinion on future implications of self-driving trucks. Method: An inductive research approach is used to explore the topic. A multi-method research strategy is applied to gather data through qualitative semi-structured interviews with 17 participants. These were divided into five different case groups. To interpret the data a thematic analysis approach was chosen. Conclusion: The main contribution is a model representing the impact of autonomous driving on competitive advantages and the implications for the logistics industry. Findings are based on the perception of experts about autonomous driving, current resources and capabilities.
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Rizzardo, Caitlan A. "Multipurpose Map Designs for GPS Surface-Vehicle Navigation: Spatial Knowledge and Advisory Functions". Wright State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=wright1316635259.
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Bergman, Marcus. "Fuel and time optimized driving of heavy trucks with respect to Euro VI legislations". Thesis, KTH, Optimeringslära och systemteori, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-154476.
Testo completoAbstract (sommario):
Saving fuel for heavy trucks travelling on a highway is possible by using the vechicles' weight and the knowledge about the road topography ahead. This can be done by a Look Ahead Cruise Controller. Such a controller can calculate an optimal driving strategy for the road segment ahead. The Look Ahead Cruise Controller is mostly used on an undulating road with a lot of up-and downhill slopes. Then the controller could increase the vehicle speed before an uphill or select the neutral gear and let the vehicle roll in a downhill slope in order to save fuel. Particle and nitrogen oxides can have a harmful effect on humans and since these are created in the combustion process of an engine, it is important to limit their presence in the exhaust gas. Therefore the Euro VI legislations are now in effect. They limit the number of particles and amount of nitrogen oxides that can be released from the vehicle. In order to meet these legislation demands the exhaust gas needs to be cleaned. Selective catalytic reduction (SCR) can be used to reduce the emission of nitrogen oxides. In order for the reduction to work as efficient as possible the catalytic substrate needs to have a high temperature. When the engine of a vehicle is working on a low engine speed and with a low torque demand, the exhaust gas temperature becomes low. This typically occurs when the vehicle is travelling in a downhill slope, either by rolling on neutral gear or rolling using engine brake. Thus the catalytic substrate is cooled, causing the catalytic process to slow down. A common way to avoid this is to let the engine work in a warming mode. However, this mode uses more fuel in order to heat the exhaust gas. The aim of this thesis is to find out if the cooling of the SCR substrate could have an affect on the optimal driving strategy found by the Look Ahead Cruise Controller.
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Torén, Anna. "Twisted trunk postures during tractor driving : with special reference to low-back load and exposure /". Uppsala : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5498-0.pdf.
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Herold, Maximilian [Verfasser], Hermann [Akademischer Betreuer] Winner e Steffen [Akademischer Betreuer] Müller. "Redundant Steering System for Highly Automated Driving of Trucks / Maximilian Herold ; Hermann Winner, Steffen Müller". Darmstadt : Universitäts- und Landesbibliothek Darmstadt, 2019. http://d-nb.info/1201820537/34.
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Lederman, George. "Data-Driven Approaches for Track Monitoring Using In-Service Trains". Research Showcase @ CMU, 2016. http://repository.cmu.edu/dissertations/831.
Testo completoAbstract (sommario):
This thesis explores data-driven approaches for monitoring rail-infrastructure from the dynamic response of a train in revenue-service. Presently, track inspection is performed either visually or with dedicated track geometry cars. Collecting and analyzing vibration data from in-service trains can offer more economical and more reliable monitoring. The high frequency with which in-service trains travel each section of track means that faults can be detected sooner than with dedicated inspection vehicles, and the large number of passes over each section of track makes a data-driven approach statistically feasible. Developing such a data-driven approach requires modeling the state of the tracks from the collected data, then detecting track anomalies as the model changes over time. Building consistent models from different passes is challenging due to the variation in the train’s speed from pass to pass, the uncertainty in the train’s position, and changes in the properties of the train itself. We study two ways of modeling the state of the tracks to address these challenges: explicit models where the track profile itself is estimated, and implicit models, where features extracted from the collected data are used to imply information about the tracks. In addition, we explore change detection methods appropriate for both modeling approaches; these would allow for monitoring to occur without human supervision. Finally, for network-level monitoring to be practical, we study how data from multiple sensors and multiple trains could be fused together. Data fusion could enable more accurate representations of the state of the tracks, and more rapid detection of track changes after they occur. The track modeling, change detection and data fusion approaches presented in this thesis are validated with simulations and with data collected from two instrumented trains. This collected data includes more than 500 passes through a 40km rail network over a three year period. We demonstrate that the proposed sensing, signal processing, and data analysis can detect numerous types of track anomalies and could facilitate safer, more efficient rail-infrastructure in the future.
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Strawn, Rachel Mayes. "Drivin' trucks, huntin' bucks, and reading Aristotle?: The rural student's college choice dilemma". W&M ScholarWorks, 2014. https://scholarworks.wm.edu/etd/1550154174.
Testo completo
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Bergvall, Johan, e Christoffer Gustavson. "The Economic Impact of Autonomous Vehicles in the Logistics Industry". Thesis, Internationella Handelshögskolan, Högskolan i Jönköping, IHH, Centre of Logistics and Supply Chain Management (CeLS), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-37816.
Testo completoAbstract (sommario):
In an ever-changing industry where competition between actors is growing, technical improvements and investments can be a way to outperform competitors and gain competitiveadvantages. In a relatively under-developed industry, technological developments may leadto major improvements and change the layout of the whole business. Purpose – The main purpose of this thesis is to investigate potential cost reductions obtained by autonomous vehicles within the Swedish logistics industry. Studying opportunities for companies tostrengthen their competitive advantage can create new markets, chances or ensure a strongmarket position. To investigate said opportunities, the following research questions werestated: What is the actual cost of implementing an autonomous vehicle? Which costs will be affected by an implementation of autonomous vehicles? How do these costs impact the Swedish logistics market seen from a cost perspective? Method – The data necessary to answer the questions was collected from document studies, literature studies and interviews. These were carried out simultaneously in an iterativeprocess. Moreover, a pragmatic philosophy was undertaken, together with an abductive approach. The data was compared with existing theory by pattern matching and analysed withthematic approach, in order to ensure the level of trustworthiness. Findings/Implications – The findings of this thesis is that autonomous vehicles willheavily impact the logistics industry. By gradually implementing autonomous vehicles, theSwedish logistics sector can save upwards of 13,4 billion SEK between 2020 and 2030.This shift towards autonomous vehicles will move jobs from the long haul sector to urbanlogistics and telecommunications. Additionally, the society will see great benefits as 90% ofall traffic accidents will not happen when all vehicles are autonomous. It is clear that theSwedish logistics industry will benefit from an implementation of autonomous vehicles.Simultaneously it will also be beneficial for the society and the Swedish welfare. Limitations – The major limitation of this thesis is the time horizon. Because of being future oriented, much data was based on external estimations that might change over time.Moreover, only costs directly connected to transportations has been investigated, leavingroom for further studies related to indirect costs, as well as the organizational impacts onfuture supply chains.
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Tomar, Abhineet Singh. "Modern Electrical/Electronic Infrastructure for Commercial Trucks : Generic Input/Output nodes for sensors and actuators in Commercial Trucks". Thesis, KTH, Radio Systems Laboratory (RS Lab), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-220183.
Testo completoAbstract (sommario):
The presence of electrical and electronic circuits in commercial trucks has increased at a very fast rate during recent decades. With advancements in embedded systems and the introduction of electric controls in the automotive industry, the design of complex electric systems for the vehicles has become one of the major design challenges. In the commercial truck industry, the development cycles are almost a decade long. Therefore, it is a big challenge to introduce a new architecture to accommodate the modern automotive technologies in the upcoming generation of trucks. Currently, the commercial truck industry relies highly on a federated electrical/electronic (E/E) architecture. In this architecture, Electronic Control Units (ECU) are responsible for computation and Input/Output operations. These ECUs are clustered into different domains based on their respective functions. However, these domains are not isolated from each other. These modules communicate with each other using a vehicular network, which is typically a controller area network in the current trucks. In the automotive industry, automation is increasing at a fast pace. As the level of automation increases, the need for high computation also increases, which increases the overall costs. This study aims to address this problem by introducing an integrated E/E architecture where all the computational power is concentrated at one place (or perhaps two or three places to allow for redundancy). This study proposes to introduce a lowcost replacement for the current ECUs with more limited computational power but with generic input/output interfaces. This thesis provides the reader with some background of the current E/E architecture of commercial trucks and introduces the reader to ECUs. Additionally, the relevant network architectures and protocols are explained. A potential solution, based upon the centralized computation based E/E architecture and its implementation are discussed followed by a detailed analysis of the replacements for ECUs. The result of this analysis, if adopted, should result in a reduction of manufacturing and design costs, as well as make the production and maintenance process easier. Moreover, this should also have environmental benefits by reducing fuel consumption.Förekomsten av elektronik och elektriska kretsar I kommersiella lastbilar has ökat i en väldigt snabb takt under de senaste decennierna. Med framsteg inom inbyggda system och introduktionen av elektroniska styrsystem i fordonsindustrin så har komplexa elektroniska system blivit en av de största designutmaningarna. I den kommersiella lastbilsindustrin där utvecklingscyklerna är nästan ett decennium, är det en stor utmaning att introducera ny arkitektur som tillgodoser all den nya teknologin som införlivas i fordonet. För närvarande så förlitar sig den kommersiella lastbilsindustrin mycket på en federated elektrisk/elektronisk (E/E) arkitektur. I denna arkitektur är elektroniska styrenheter (ECU) ansvariga för beräkningar och I/O (Input/Output) operationer. Dessa ECU:er är samlade i olika domäner baserade på dess funktioner. Domänerna är dock inte isolerade från varandra. De här modulerna kommunicerar därför med varandra med hjälp av ett fordonsnätverk, typiskt en CAN (Controller Area Network) i nuvarande lastbilar. I fordonsindustrin ökar automatiseringen i en snabb fart. I takt med att automatiseringen ökar så ökar även behovet av snabba och energiintensiva beräkningar, vilket i sin tur ökar den totala kostnaden. Denna studie har som mål att adressera det här problemet genom att introducera en integrated E/E arkitektur där all beräkningskraft är koncentrerad till en plats (eller två eller tre platser för att tillåta överskott). Den här studien föreslår att introducera en ersättning av nuvarande ECU:er till en låg kostnad, med lägre beräkningskraft och generiska I/O gränssnitt. Studien föreslår också ersättningar av nuvarande fordonsnätverk. Den här uppsatsen förser läsaren med viss bakgrund till den nuvarande E/E arkitekturen för kommersiella lastbilar och introducerar läsaren till ECU:er. Dessutom förklaras de relevanta nätverksarkitekturerna och protokollen. En potentiell lösning som baseras på den integrated E/E arkitekturen och dess implementering diskuteras med fokus på en detaljerad analys av ersättningarna till ECU:er. Resultatet av den här analysen skulle, om den adopteras, medföra minskning av tillverknings- och designkostnader samt leda till en förenkling av produktion och underhåll. Utöver det så bör det även ha miljöfördelar genom minskad bränsleförbrukning.
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Attravanam, Siddarth Kashyap. "Identifying Operating Conditions of Tires During Highway Driving Maneuvers". The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1534456018582412.
Testo completo
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Nilsson, Philip. "Topology optimization of a swing arm for a track driven vechile". Thesis, Umeå universitet, Institutionen för fysik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-149608.
Testo completoAbstract (sommario):
The development in additive manufacturing methods has cleared the path for topology optimizationby making it possible to produce complex geometries, which would not be possible to produce bytraditional manufacturing methods. Topology optimization uses iterative structural computations tond an optimal material distribution given a maximum optimization domain, load cases and/or otherstructural criteria. The relation between retained mass and structural performance of a swing armfor the vehicle BvS10 was examined for two different materials. The first material was an estimate of an additive manufactured material and the other for a high structural steel. Given the extreme load cases, the geometrical limits of the swing arm and by specifying how much mass was to be retained the stiffness was to be maximized. The optimization was performed using an elastic material model in thecommercial software ANSYS. This elastic material models was based on standard material parameters of steel. Three geometries were generated, namely OG100, OG90 and OG80, which corresponded to 101 %, 87 % and 81 % of the mass of the original swing arm, respectively. The optimization procedurewas combined with geometry modications in SpaceClaim to simplify the obtained geometries. All these geometries consisted of a hollow geometry with a greater width compared to the original geometry. The geometries were then evaluated using multilinear plastic material models based on respective material. Using the additive manufactured material model no generated geometry could perform structurally better than the original swing arm. This indicates that greater material properties must be obtainedin order to be able to reduce the weight of the swing arm. By using the material properties of the highstructural steel, it was found that at least 31.3 kg per vehicle could be reduced by using the optimizedgeometry OG80, and still not perform structurally worse than of the original swing arm.Utvecklingen inom additiv tillverkning har öppnat vägen för topologioptimering genom att kunna producera komplexa geometrier, som inte skulle vara möjliga att tillverka med hjälp av traditionella tillverkningsmetoder. Topologioptimering använder iterativa hållfasthetsberäkningar för att finna den optimala materialfördelning givet en maximal optimeringsdomän, lastfall och/eller andra strukturella kriterier. Relationen mellan bibehållen massa och strukturella prestationer hos en pendelarm till fordonet BvS10 har undersökts för två olika material. Det ena materialet var en uppskattning av ett additivt tillverkat material och det andra materialet var ett höghållfasthetsstål. Givet dem extrema lastfall, geometriska begränsningar hos pendelarmen och genom specficera hur mycket massa som skulle behållas så skulle styvheten maximeras. Optimeringarna utfördes med en elastisk materialmodell i den kommersiellamjukvaran ANSYS. Denna elastiska materialmodell var baserad på klassiska materialparametrarfor stål. Tre geometrier genererades. Optimeringsproceduren användes i kombination med geometriska modikationer i SpaceClaim för att förenkla de optimierade geometrierna. Dessa var OG100, OG90 och OG80, vilka motsvarade 101 %, 87 % och 81 % av pendelarmens originalvikt. Alla geometrier bestod av en ihålig geometri med större bredd än originalarmens. Geometrierna utvärderades sedan med hjälp av multilinjära plastiska materialmodeller baserat på respektive material. Ingen av dessa geometrier kunde prestera bättre än originalarmen när det additivt tillverkade materialet användes. Detta indikerar att bättre materialegenskaper måste uppnås för att kunna reducera vikten hos pendelarmen. Genom attanvända höghållfasthetsstålet upptäcktes att åtminstone 31.3 kg per fordon kunde reduceras genom attanvända OG80, och fortfarande inte prestera sämre än originalarmen.
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Törnell, Axel. "Möjligheter för automatiserade godstransporter I Västerbotten : Vilken påverkan har väginfrastruktur för potentialen till automatiserade transportsystem i region Västerbotten?" Thesis, Umeå universitet, Institutionen för geografi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-184377.
Testo completoAbstract (sommario):
The technology behind self-driving trucks in currently under development for deployment on public road. The objective of this study is to explore and understand the number of industries that could be reached by self-driving trucks with the limits of Västerbottens current road network. The effect from implementing self-driving trucks is an emerging research field. We do not understand to what extent the physical infrastructure affect which industries may be able to use self-driving trucks since there is a lack of exploration and research within the scientific literature. The thesis has been conducted by a literature study, interviews, and a spatial analysis. The spatial analysis examined the potential for self-driving trucks to access industries depending on what road infrastructure self-driving trucks are assumed to be able to operate. The number of industries that self-driving trucks can access was calculated for four different subsets of the road networks: The European highway network, National highway network, Functional priority road network and roads with driving lane with over 5m. This resulted in the conclusion that the European highway network had the lowest number of industries within the search radiuses, a considerate amount of all industries (49%) was still within a 1 km radius. The road type “Driving lane with over 5m” having a clear majority of the industries with a total of 94% of the industries within a 1 km radius. The findings of this study suggest that self-driving trucks which are capable of operating only at a limited part of the road network still potentially could be used for a relatively large number of industrial freight transport flows in Västerbotten. This could indicate that self-driving trucks with a limited operating design domain could address a substantial share of the freight transport market.
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Held, Manne. "Optimal Speed and Powertrain Control of a Heavy-Duty Vehicle in Urban Driving". Licentiate thesis, KTH, Reglerteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-215116.
Testo completoAbstract (sommario):
A major challenge in the transportation industry is how to reduce the emissions of greenhouse gases. One way of achieving this in vehicles is to drive more fuel-efficiently. One recently developed technique that has been successful in reducing the fuel consumption is the look-ahead cruise controller, which utilizes future conditions such as road topography. In this this thesis, similar methods are used in order to reduce the fuel consumption of heavy-duty vehicles driving in environments where the required and desired velocity vary. The main focus is on vehicles in urban driving, which must alter their velocity due to, for instance, changing legal speed restrictions and the presence of intersections. The driving missions of such vehicles are here formulated as optimal control problems. In order to restrict the vehicle to drive in a way that does not deviate too much from a normal way of driving, constraints on the velocity are imposed based on statistics from real truck operation. In a first approach, the vehicle model is based on forces and the cost function involves the consumed energy. This problem is solved both offline using Pontryagin's maximum principle and online using a model predictive controller with a quadratic program formulation. Simulations show that 7 % energy can be saved without increasing the trip time nor deviating from a normal way of driving. In a second approach, the vehicle model is extended to include an engine and a gearbox with the objective of minimizing the fuel consumption. A fuel map for the engine and a polynomial function for the gearbox losses are extracted from experimental data and used in the model. This problem is solved using dynamic programming taking into consideration gear changes, coasting with gear and coasting in neutral. Simulations show that by allowing the use of coasting in neutral gear, 13 % fuel can be saved without increasing the trip time or deviating from a normal way of driving. Finally, an implementation of a rule-based controller into an advanced vehicle model in highway driving is performed. The controller identifies sections of downhills where fuel can be saved by coasting in neutral gear.En stor utmaning för transportsektorn är hur utsläppen av växthusgaser ska minskas. Detta kan åstadkommas i fordon genom att köra bränslesnålare. En nyligen utvecklad teknik som har varit framgångsrik i att minska bränsleförbrukningen är framförhållningsreglering, som använder framtida förhållanden så som vägtopografi. I denna avhandling används liknande metoder för att minska bränsleförbrukningen i tunga fordon som kör i miljöer där önskad och tvingad hastighet varierar. Fokus ligger framförallt på fordon i stadskörning, där hastigheten måste varieras beroende på bland annat hastighetsbegränsningar och korsningar. Denna typ av körning formuleras här som optimala reglerproblem. För att hindra fordonet från att avvika för mycket från ett normalt körbeteende sätts begränsningar på tillåten hastighet baserat på statistik från verklig körning. Problemet angrips först genom att använda en fordonsmodell baserad på krafter och en kriteriefunktion innehållande energiförbrukning. Problemet löses både offline med Pontryagin's maximum princip och online med modellprediktiv reglering baserad på kvadratisk programmering. Simuleringar visar att 7 % energi kan sparas utan att öka körtiden eller avvika från ett normalt körbeteende. Problemet angrips sedan genom att utöka fordonsmodellen till att också innehålla motor och växellåda med målet att minimera bränsleförbrukningen. Specifik bränsleförbrukning och en polynomisk approximation av förlusterna i växellådan är extraherade från experiment och används i simuleringarna. Problemet löses genom dynamisk programmering som tar hänsyn till växling, släpning och frirullning. Simuleringar visar att 13 % bränsle kan sparas utan att öka körtid eller avvika från normalt körbeteende genom att tillåta frirullning. Slutligen görs en implementering av en regelbaserad regulator på en avancerad fordonsmodell för ett fordon i motorvägskörning. Regulatorn identifierar sektioner med nedförsbackar där bränsle kan sparas genom frirulllning.
QC 20171011
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Morgan, Lauren Jayne. "The influence of whole-body vibration and axial rotation on musculoskeletal discomfort of the neck and trunk". Thesis, Loughborough University, 2011. https://dspace.lboro.ac.uk/2134/9138.
Testo completoAbstract (sommario):
Elements of an individuals occupational exposure, such as their posture can affect their comfort during work, and also their long term musculoskeletal health. Knowledge as to the extent of the influence of particular aspects of the exposures can help in providing guidance on risk evaluation, and direct future technical design focus. In many situations the exposures interact, and even if the effects of individual exposures are understood, the interactions are often less so. This is certainly the case with off-road driving exposures. Specific investigations have focussed on the effects of vibration exposure, resulting in the development of international standards and guidelines on measurement and evaluation of exposure. Consideration of the posture of the operator can be accomplished through postural assessment tools, although none of the currently available methods are developed specifically for use within a vehicle environment. The issues of both the posture of the operator and the seated vibration exposure are particularly apparent in off-road agricultural driving environments, where the driving task dictates that operator is often required to maintain specific postures whilst also exposed to whole-body vibration. In agriculture, many of the tasks require the operator to maintain axially rotated postures to complete the task effectively. The analysis of the combined effects of the axial rotation of the operator and the whole-body vibration exposure has been limited to a few studies within the literature, and is currently poorly understood. The overall aim of the thesis was to assess the influence of axial rotation and whole-body vibration on the musculoskeletal discomfort of the neck and trunk, in order that the true extent of the exposure risk may be evaluated. A field study was conducted to determine the common characteristics of some typical exposures, to provide a basis for the laboratory studies. A survey of expert opinion was conducted, examining the knowledge and experience of experts in assessing the relative influence of axial rotation and whole-body vibration on operators musculoskeletal health. The main investigations of the thesis are focussed in the laboratory, where the objective and subjective effects of axial rotation (static and dynamic) and whole-body vibration were investigated. Objective measures included the investigation of muscular fatigue in response to exposures. The tasks investigated in the field study indicated that the exposures often exceed the EU Physical Agents Exposure Limit Value, and that the axial rotation is a large component of the postures required. The survey of expert opinion concluded that combined exposure to axial rotation and whole-body vibration would increase the risks of lower back pain, and that acknowledgement of combined exposures should be included when assessing for risk. The results of the laboratory studies indicated that the greatest discomfort was present when subjects were exposed to axial rotation in the neck and shoulders. Out of the 8 muscles investigated, at most 6 of the 8 indicated fatigue during an experimental exposure. The muscle group which was affected most by the exposures was the m. trapezius pars decendens. Findings demonstrated that when subjects were exposed to axial rotation and whole-body vibration they indicated discomfort and their muscles fatigued. However, there was poor correlation between the sites of discomfort and the location of muscular fatigue. The discomfort findings suggest that there is an increased risk of discomfort from experiencing axial rotation together with whole-body vibration. Investigations of muscular fatigue do not substantiate this finding.
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Gresset, Constance, e David Morda. "Assessing the human barriers and impact of autonomous driving in transportation activities : A multiple case study". Thesis, Jönköping University, IHH, Företagsekonomi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-52677.
Testo completoAbstract (sommario):
Background: The transport industry is facing new challenges such as increased competition between the actors and an increasing shortage of truck drivers. Implementing new technologies such as autonomous driving can represent a solution for companies to increase their competitiveness and gains. However, implementing such an innovative solution leads to a certain resistance to change that has to be dealt with, as well as concerns about the current jobs within the industry. Purpose: The purpose of this thesis is to assess the resistance to change linked to implementing this technology within Logistics Service Providers, provide solutions to overcome this resistance, as well as assessing the impact on jobs. Method: An inductive multiple case study has been used to conduct this research. The data was gathered from 12 semi-structured interviews with experts related to the transport industry. Then, thematic data analysis has been used to provide insights. Conclusion: The results show that the resistance is characterized by barriers to the technology and the resistance from the people, that support and communication is the key factor for successful implementation and that the truck driving professions will evolve considerably.