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<p>Det svenska förarprovet har vuxit fram ur praktisk yrkeserfarenhet. Oavsett vilken trafikinspektör som bedömer ett specifikt körprov ska bedömningen göras lika. Kognitiva egenskaper bedöms i körprovet genom att observera handlingar och beteenden. Syftet med denna uppsats var att ur ett teoretiskt perspektiv undersöka hur trafikinspektörer bedömer kognition, för att undersöka vilka likheter och skillnader som finns. Tre analyser gjordes utifrån tolv intervjuer med trafikinspektörer vid två av Vägverkets förarprovskontor.</p><p>Trafikinspektörerna ombads beskriva vad som är viktigt hos en bilförare. Samtliga formella kriterier för körprovet nämndes av någon informant. Utöver kriterierna nämndes även många andra begrepp av ett fåtal personer vardera. Dessa begrepp kan räknas till områdena kognitionspsykologi, allmän psykologi, bilkörning och övergripande egenskaper. De tre mest nämnda begreppen var uppmärksamhet, erfarenhet och riskmedvetande.</p><p>Sju körprovskriterier definierades av trafikinspektörerna. Många olika begrepp användes för att definiera kriterierna och samtliga kriterier definierades olika av informanterna. Definitionerna delades in i kategorier och de kategorier som användes för samtliga kriterier var förberedelser, handlingar och perception.</p><p>Ur det som sades av informanterna gjordes en analys om hur begrepp kopplas samman med varandra, för att hitta alla associationer som görs till varje begrepp. Många olika kopplingar kunde hittas genom denna analys och av dessa nämndes hälften av enbart någon informant. Två kopplingar nämndes av elva av informanterna. Den ena var manövrering – automatisering, den andra var uppmärksamhet – syn.</p><p>Studien påvisade både likheter och skillnader i åsikter informanterna emellan. I viss utsträckning använda sig informanterna av samma begrepp, men de lade olika innebörder i begreppen. Trafikinspektörernas olika synsätt medför en risk för att de bedömer körprov olika trots att de använder samma bedömningskriterier.</p> / <p>The Swedish driving license test has developed from practical professional experience. Regardless of which traffic inspector judges a specific driving test, the judgement is to be equal. Cognitive qualities are judged in the driving test by observing actions and behaviours. The purpose of this essay was to investigate, from a theoretical perspective, how traffic inspectors judge cognition, in order to investigate differences and similarities. Three analyses were made, based on twelve interviews with traffic inspectors working at two of the Swedish Road Administration’s offices for driving license tests.</p><p>The traffic inspectors were asked to describe what is important in a car driver. All formal driving test criteria were mentioned by some informant. In addition to the criteria, many other concepts were mentioned by a few persons each. These concepts belong to the areas cognitive psychology, general psychology, car driving and overall qualities. The three most mentioned concepts, including criteria and other concepts, were attention, experience and risk awareness.</p><p>Seven driving test criteria were defined by the traffic inspectors. Many different concepts were used to define the criteria and all criteria were defined differently by the informants. The definitions were divided into categories. The categories preparations, actions and perception were used for all criteria.</p><p>An analysis about how concepts were connected to each other was made, in order to find all associations made with each concept. Many different connections were found in this analysis and more than half of these were mentioned by only one informant.</p><p>Two connections were mentioned by eleven informants. One of these was manoeuvring – automation, the other was attention – vision.</p><p>Both similarities and differences in opinions were found among the informants in this study. The informants used the same concepts to some extent, but they associated different meanings with the concepts. The traffic inspectors’ differences in opinions lead to a risk of judging driving tests differently, although the same judgement criteria are used.</p>

The objective of this thesis is to analyse driving behaviour and to characterize the effectsof an efficient way of driving, termed eco-driving, that enables the driver to reduce fuelconsumption and CO2emissions.The approach used to assess driving style is a collection of data from a CAN bus of acar equipped with OBD-II (on-board diagnostic) system. The driving experiment wasperformed for nine drivers who drove in a normal way or regular driving style and onedriver was an eco-driver who drove in an economical driving style. The driving routewas approximately 18.7 kms (which took between 25 to 30 minutes) in Halmstad city,Sweden.The drivers are compared using a statistical analysis of the driving parameters such as,speed, accelerator (gas pedal) and brake pressure, which are obtained from CAN busdata. A hierarchical clustering algorithm also used to classify the drivers based on theaverage result of the signals.In the results, a driving difference between the eco-driver and the normal drivers is visi-ble, most of the normal drivers have more or less similar behaviour. The average speed ofthe eco-driver lower than the normal drivers and the accelerator (gas pedal) result is alsoshown less usage by the eco-driver than the normal drivers. On the other hand, the eco-driver has braked more often than the normal drivers, but gently. Nevertheless, differenttraffic conditions during the experiment obstructs comparisons between the drivers.

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.

Driver fatigue is a complex phenomenon that has a range of causal factors including sleeprelated and task-related factors. These manifest as different safety and performance outcomes. Extensive research has been applied to linking these factors to performance impairment. However, little research focuses on the mechanisms by which this link exists. This research project therefore focuses on the processes underlying how driving performance is controlled and maintained during the development on non-sleep-related driver fatigue. The main aim was to establish whether progressive impairment of driving control over a prolonged drive could be attributed to a depletion of attentional resources, as proposed by Resource Theory, or to a withdrawal of effort, as proposed by Effort-Regulation Theory. As a multicomponent skill, driving requires perception, cognition and motor output. The secondary aim of this research was therefore to assess whether a prolonged drive impairs stage-specific information processing. Participants (n=24) in three experimental groups performed a 90-minute simulated drive wherein they were expected to keep the bonnet of a car on a lane (tracking task). The three groups differed in terms of lane width: small, medium and large, corresponding to low, medium, and high task-demand, respectively. To assess the impacts of this task on stagespecific information processing, participants performed a set of resource specific tests before and after the prolonged drive. Each task had two difficulty variations to ensure that performance decrement was due not only to the task-characteristic, but specifically to resource depletion. The tests probing information processing were: a modified Fitts' tapping task for motor programming, a digit recall task for perception, and an object recognition reading task for cognition. Performance was measured as lateral deviation of the car. Physiological measures included heart rate frequency (HR) and various time- and frequencydomain heart rate variability (HRV) parameters, eye blink frequency and duration. The Borg CR-10 scale was used to evaluate subjective effort and fatigue during the task. Driving control declined over time and was supplemented by HR, HRV, blink frequency and duration, indicating an increase in parasympathetic activity (or a reduction in arousal). An increase in blink frequency was considered as a sign of withdrawal of attentional resources over time. Driving control declined to a greater extent in the large road width group and reflected a lower parasympathetic activity, whereas the inverse was observed for the small road width group. Resource tests reveal a non-specific impairment of information processing following the prolonged drive. However, this was accompanied by an increase in parasympathetic activity. Overall, results indicate that Effort-Regulation Theory better accounts for the impairment of driving control in prolonged driving than does Resource Theory. This suggests that the impact of fatigue is guided more by task goals and intrinsic motivation than by the manner in which the fatigue state developed. Moreover, performance impairment by effort-regulation is dependant more on time on task than on task-demand

During impact driving of open-ended piles through cohesion-less soil the internal soil column may mobilize enough internal shaft resistance to prevent new soil from entering the pile. This phenomena, referred to as soil plugging, changes the driving characteristics of the open-ended pile to that of a closed-ended, full displacement pile. If the plugging behavior is not correctly understood, the result is often that unnecessarily powerful and costly hammers are used because of high predicted driving resistance or that the pile plugs unexpectedly such that the hammer cannot achieve further penetration. Today the user is generally required to model the pile response on the basis of a plugged or unplugged pile, indicating a need to be able to evaluate soil plugging prior to performing the drivability analysis and before using the results as basis for decision. This MSc. thesis focuses on soil plugging during impact driving of open-ended piles in cohesion-less soil and aims to contribute to the understanding of this area by evaluating models for predicting soil plugging and driving resistance of open-ended piles. Evaluation was done on the basis of known soil plugging mechanisms and practical aspects of pile driving. Two recently published models, one for predicting the likelihood of plugging and the other for predicting the driving resistance of open-ended piles, were compared to existing models. The main outcomes from the model evaluations are: • Internal shaft resistance, pile diameter and pile velocity/acceleration were found to be the primary input parameters affecting the result in the models used to predict if soil plugging is likely to occur. • The pile diameter was shown to have less influence on the calculated driving resistance in the recently published model, derived from measurements of plug length ratios, compared to in the existing model. This thesis also includes a full-scale field study conducted during the initial piling operations for the construction of the new Värtahamnen seaport in Stockholm (Sweden). The soil conditions cause the piles to be driven through very dense post glacial moraine, in which little is known about soil plugging. The drivability performance of 146 open-ended and closed-ended steel pipe piles with diameters ranging from 914-1168 mm was compared through analysis of driving records. The aim was to evaluate if open-ended piles resulted in a drivability related gain and if so during which part of the installation process. The driving records were used to quantify the performance in terms of driving time and energy required to drive the piles. The main conclusions from the field study are: • Significant time savings were achieved by using open-ended piles instead of closedended piles. The time advantage was bigger during impact driving, compared to vibratory driving, and on average the impact driving of open-ended piles took 9 minutes versus 26 minutes for closed-ended piles. • Contrary to what was expected, namely that the open-ended piles would result in lower driving resistance, the results indicate that the majority of the time savings came from open-ended piles being more stable during driving and thereby requiring fewer adjustments. / Under slagdrivning av öppna pålar i friktionsjord förekommer det att den interna jordpelaren mobiliserar tillräckligt mycket internt mantelmotstånd för att förhindra inträngning av ny jord. Detta fenomen, på svenska vanligen kallat jordpluggning, medför att drivbeteendet för pålen övergår till att likna det hos en sluten och massundanträngande påle. Oförmåga att på ett korrekt sätt beakta jordpluggning medför ofta att drivmotståndet för öppna pålar antingen överskattas, vilket medför att onödigt kraftfull och kostsam utrustning används, eller underskattas vilket kan medföra att pålen pluggar och inte kan drivas till avsett djup. I dagsläget kräver drivbarhetsanalyser generellt sett att användaren måste modellera pålen som en pluggad eller opluggad påle. Detta medför att det finns ett behov att kunna utvärderajordpluggning innan drivbarhetsanalysen genomförs, samt även vid utvärdering av resultaten från drivbarhetsanalysen. Detta examensarbete fokuserar på jordpluggning vid slagdrivning av öppna pålar i friktionsjord och syftar till att öka kunskapen inom området genom att utvärdera modeller som kan användas för att uppskatta huruvida jordpluggning är sannolikt, samt modeller för att uppskatta drivmotståndet för öppna pålar. Utvärderingen av nämnda modeller skedde med utgångspunkt i kända mekanismer som förknippas med jordpluggning, samt i praktiska aspekter av påldrivning. Två nyligen publicerade modeller, en avsedd att utvärdera huruvida pluggning är sannolikt och den andra för att uppskatta det förväntade drivmotståndet, jämfördes med befintliga modeller för samma ändamål. De huvudsakliga slutsatserna av modellutvärderingen är: • Internt mantelmotstånd, pålens diameter samt pålens hastighet/acceleration var de faktorer som hade störst inverkan på resultatet hos de modeller som avser utvärdera huruvida jordpluggning är att förvänta. • Pålens diameter visade sig få mindre inverkan på beräknat drivmotstånd i den nyligen publicerade modellen, baserad på mätningar av plugglängd relativt penetrationsdjup, jämfört med i den befintliga modellen. Examensarbetet innefattar även en fältstudie genomförd under inledningen av pålningsarbetet vid uppförandet av nya Värtahamnen i Stockholm. Markförhållandena på platsen medför att pålarna drivs genom bottenmorän, ett jordförhållande där det i stor utsträckning saknas erfarenheter relaterade till jordpluggning. Med hjälp av pålprotokoll jämfördes drivbarheten hos 146 öppna och slutna pålar med diametrar 914-1168 mm. Målet var att fastställa huruvida öppna pålar medförde ökad drivbarhet och i så fall under vilket skede av drivprocessen. Pålprotokollen användes för att kvantifiera vinsten i form av drivtid samt erforderlig drivenergi. De huvudsakliga slutsatserna från fältstudien är: • Betydande tidsvinst kunde påvisas för öppna pålar, jämfört med stängda pålar. Tidsvinsten var större under slagdrivning än under vibrationsdrivning och i snitt 9 minuter jämfört med 26 minuter för stängda pålar. • I motsats till det förväntade utfallet, nämligen att de öppna pålarna inte skulle plugga, antyder resultaten att majoriteten av tidsvinsten kan kopplas till att de öppna pålarna var mer stabila under drivning vilket resulterade i färre korrigeringar

Driving anxiety that has developed following crashes has been studied relatively frequently, but anxiety per se and its effects on driving has not as yet garnered much attention in the literature. The current study included 1121 participants and found higher levels of general anxiety were related to a wide variety of dangerous driving behaviors. While there were clear and expected sex differences on many dangerous driving variables, there were still more such differences with regard to anxiety levels and independent of sex, higher levels of anxiety were associated with greater levels of dangerous driving. Of particular import, it was found that the high anxiety group had caused significantly more crashes and engaged in more DUI episodes than the low and/or medium anxiety groups. Taken as a whole, the results suggest there is a tremendous need for more research in the area of anxiety and dangerous driving and that interventions for highly anxious drivers may well be warranted.