This bachelor thesis examines how redundancy is used to tolerate a process crash fault on a server in a system developed for emergency situations. The goal is to increase the availability of the service the system delivers. The redundant solution uses hot passive replication with one primary replica manager and one backup replica manager. With this approach, code for updating the backup, code for establishing a new primary and code to implement fault detection to detect a process crash has been written. After implementing the redundancy, the redundant solution has been evaluated. The first part of the evaluation showed that the redundant solution can deliver a service in case of a process crash on the primary replica manager. The second part of the evaluation showed that the average response time for an upload request and a download request had increased by 31\% compared to the non-redundant solution. The standard deviation was calculated for the response times and it showed that the response time of an upload request could be higher compared to the average response time. This large deviation has been investigated and the conclusion was that the database insertion was the reason.

Ce mémoire s’intéresse à la conception robuste de systèmes complexes dans le cadre de l’ingénierie système et de la méthode First Design. Ces travaux s’appliquent plus particulièrement aux prestations en choc frontal de véhicules de la gamme Renault. L’objectif principal de ces travaux est de proposer une méthode de conception robuste basée sur la modélisation numérique des prestations crash du véhicule. Cette stratégie vise à assurer la robustesse du produit dès la phase de conception, afin d’éviter des modifications de conception tardives et coûteuses, conséquences d’apparition de problèmes durant le cycle de validation ou la vie série du véhicule. Les spécificités du crash sont le coût important des simulations, la forte non linéarité du phénomène, ainsi que les bifurcations de comportement. Ces particularités rendent les méthodes classiques de conception robuste peu efficaces ou très couteuses. Afin de répondre à ce problème, nous développons une méthode originale, baptisée détection de défaillances, permettant d’identifier les problèmes de robustesse en crash, afin de les corriger dès le cycle de conception. Cette méthode est basée sur l’utilisation des techniques d’optimisation par les plans d’expériences. La méthode développée vise aussi à intégrer l’expertise des concepteurs crash afin de localiser rapidement les défaillances, ce qui permet de limiter le nombre de simulations nécessaires. La contrepartie d’une méthode de conception robuste reposant sur la simulation numérique est la nécessité d’avoir un bon niveau de confiance dans les résultats du modèle. On propose donc dans ce mémoire des améliorations des modèles éléments finis des véhicules Renault, afin d’améliorer la qualité de la simulation. Ces travaux vont dans le sens d’un remplacement des prototypes physiques par des prototypes numériques dans l’industrie, enjeu majeur permettant la réduction des coûts et des délais de développement. Cet enjeu est particulièrement important dans un secteur automobile très concurrentiel, où la survie d’un constructeur dépend de ses coûts et de sa réactivité face au marché. / This PhD thesis deals with robust design of complex products, within the framework of system engineering methods, such as First Design. This work focuses on frontal crashworthiness of Renault vehicles. The main goal of this PhD is to develop a robust design method based on crashworthiness numerical simulation. This method aims at ensuring the robustness of a vehicle crashworthiness right from the design stage of the product, in order to avoid costly design modifications, necessary when problems are found during the validation cycle or the life cycle of the product. Characteristics of crashworthiness phenomena are a high cost of numerical simulation, highly non-linear and bifurcative behaviour. Due to this behaviour, classic robust design methods would be unefficient or very expensive to use. In order to face this problem, we develop an original robust design method, based on optimization using design of experiments method. The goal of this method is to identify crash failures as soon as possible in the design stage, in order to correct them. This method also aims at integrating knowledge from the crash engineers, in order to find crash failures quickly, using as few simulations as possible. A challenge we meet when using numerical simulation of the crashworthiness is the need to trust the results of the model. This thesis also deals with improvements in the crash models at Renault. This work is well suited for a very competitive industry such as the automotive, where car manufacturers need to replace physical prototypes with numerical ones, in order to reduce design costs and be more reactive.

Kyoto University (京都大学) / 0048 / 新制・論文博士 / 博士(工学) / 乙第12650号 / 論工博第4078号 / 新制||工||1547(附属図書館) / 29728 / (主査)教授 辻 伸泰, 教授 落合 庄治郎, 教授 乾 晴行 / 学位規則第4条第2項該当

This dissertation uses quantitative analysis to provide insights for the urban and transportation policy-making process in order to manage two transportation externalities: road safety and air pollution in Bogotá Colombia. I performed a safety transportation risk analysis, which shows a high fatality and injury risk from road crashes in Bogota. I then analyzed safety-related benefits and costs of crash avoidance technology used in transit buses. My analysis reveals that despite of the life-safety benefit expected, Bogota’s values of statistical life and injuries make an investment on the technology for buses fall into the economically unjustified ranges. To analyze traffic related air pollution emissions, I developed a link-based emission model, which then it’s used to explore the traffic-related air pollution impacts of a highway capacity enhancement plan and a scrappage program for private cars. I use a bottom-up model that couples detailed activity data from a TAM, developed in EMME/4, with various emissions factors to develop a high-resolution road traffic emissions inventory for Bogotá. In particular, I use three emission models to produce the traffic related emission inventory, which includes exhaust emissions of five criteria air pollutants: Carbon monoxide (CO), Nitrogen Oxide (NOx), Sulphur oxides (SO2), Particulate Matter (PM, particles with diameters of 10 micrometers and smaller), and Volatile Organic Compound (VOC) emissions generated by hot-stabilized vehicle activity. The on-road vehicle emission model developed as part of this work marks an important turn over previous tools, because it opens the possibility to integrate environmental and transportation policy-making in Bogota. Integrating transportation and environmental policies has the potential to move the focus of environmental programs from “end-of-the-pipe” solutions to holistic analysis of how the land use, transportation systems and vehicle technology decisions play out on the levels of pollution in the city.

A finite element model of fibre metal laminate (FML) fuselage was developed in order to evaluate its impact response under survivable crash event. To create a reliable crash finite element (FE) model of FML fuselage, a ‘building block approach’ is adapted. It involves a series of validation and verification tasks in order to establish reliable material and damage models, verified impact model with structural instability and large displacement and verified individual fuselage structure under crash event. This novel development methodology successfully produced an FE model to simulate crash of both aluminium alloy and FML fuselage under survivable crash event using ABAQUS/Explicit. On the other hand, this allows the author to have privilege to evaluate crashworthiness of fuselage that implements FML fuselage skin for the whole fuselage section for the first time in aircraft research field and industry. The FE models consist of a two station fuselage section with one meter longitudinal length which is based on commercial Boeing 737 aircraft. For FML fuselage, the classical aluminium alloy skin was replaced by GLARE grade 5-2/1. The impact response of both fuselages was compared to each other and the results were discussed in terms of energy dissipation, crushing distance, failure modes, failure mechanisms and acceleration response at floor-level. Overall, it was observed that FML fuselage responded similarly to aluminium alloy fuselage with some minor differences which conclusively gives great confidence to aircraft designer to use FML as fuselage skin for the whole fuselage section. In terms of crushing distance, FML fuselage skin contributed to the failure mechanisms of the fuselage section that lead to higher crushing distance than in aluminium alloy fuselage. The existence of various failure modes within FML caused slight differences from the aluminium fuselage in terms of deformation process and energy dissipation. These complex failure modes could potentially be manipulated to produce future aircraft structure with better crashworthiness performance.

Traumatic brain injuries (TBIs) are injuries to the brain associated with the transfer of energy from some external source. There are an estimated 1.4 million TBIs each year, and about half are due to transportation crashes (NINDS, 2007). Driver distraction is defined as a process or condition that draws a driver's attention away from driving activities toward a competing activity (Sheridan, 2004) and has been identified as an under-examined issue for TBI populations (Cyr, et al., 2008). The interaction between the cognitive impairments related to TBIs and the competing demands from driver distraction may be especially problematic. The goal of this dissertation is to investigate the effect of driver distraction on individuals with TBI. This dissertation uses several approaches and data sources: crash data, a TBI registry, a survey of TBI drivers, and an on-road driving study of TBI and non-TBI drivers. Results demonstrate that a subset of TBI drivers are more willing to engage in distracting tasks and they are more likely to have received speeding tickets. TBI drivers involved in crashes were less likely to wear seatbelts and were more likely to be involved in multiple crashes compared to all other drivers in crashes. Additionally, a subset of TBI drivers exhibits more risk-taking while driving that may result from the TBI or a predisposition to take risks. A Bayesian approach was used to analyze the effect of distracting tasks on driving performance of TBI drivers in an on-road study. A simulator study of non-TBI drivers was used to develop prior distributions of parameter estimates. The distracting tasks include a CD selecting task, a coin sorting task, and a radio tuning task. All of the tasks contained visual-manual components and the coin sorting task contained an additional cognitive component associated with counting the currency. This suggests that TBI drivers exhibited worse driving performance during a coin sorting task than the non-TBI drivers in terms of the standard deviation of speed and maximum lateral acceleration of the vehicle. This suggests that the cognitive component of the coin sorting task may be causing the decreased performance for the TBI drivers. Across all tasks, TBI drivers spent a larger percent of the task duration looking at the task with a larger number of glances towards the distraction task than the non-TBI drivers. Driver distractions with cognitive components may be especially problematic for TBI drivers. Future work should investigate if this effect is consistent across more complex cognitive driver distraction tasks (e.g., cell phone usage) for this population. Additionally, future work should validate the high proportion of TBI drivers involved in multiple crashes.

I den här uppsatsen undersöks röstkvalitén betydelse för att förmedla information från utvalda filmerfrån Youtube-kanalen Crash Course för att se i vilken mån informationen förtydligas. Syftet meduppsatsen är att skapa en medvetenhet hos medieproducenter om att rösten har betydelse för hur deutformar informationen, och genom att tillämpa en modell för röstkvalité kan de jobba systematisktmed detta. Uppsatsen analyserar tre olika filmer med tre skilda ämnen från Youtube-kanalen.Materialet undersöks genom en kvalitativ analys enligt van Leeuweens struktur till anknytningsteorinsfyra maximer och designteori från multimedia principer. Resultatet tydde på att kategorierna styrka,mörkt och ljust i rösten var viktigast i röstkvalitén. När det gäller de fyra maximerna var begriplighetoch kvantitet de variabler som behövdes för att skapa ett socialt band mellan informant ochpresentatör. Det krävs vidare empirisk forskning för att ge en kompletterande bild av mönster som kanunderlätta en social koppling till informanten.

Distracted driving is a dangerous activity that continues to claim lives on roadways throughout the United States. A goal of this research was to collect distracted driving behavior data through observation in the field. A methodological approach was devised to keep data collection consistent across the observation periods. Analysis of the data provided information regarding trends in distraction type or driving behavior while engaging in a secondary activity. In combination with the observational portion of this research, another key component to understanding distracted driving was the crash report narrative key word search. By searching through the crash reports, it was determined which key words have high discriminating powers that indicate distraction was a key component to a crash. Additionally, the key word search demonstrated how accurately distraction related crashes are reported via the crash report form. This research contributed to the existing literature regarding distracted driving and also expanded the methods of research that are currently in use.

This thesis seeks to simulate the impact on the human foot on the car bumper. The opening section deals with requirements as to the current passive safety features aiming to mitigate the consequences of such impact. The thesis also describes the construction of a human foot impactor, its certification via both static and dynamic tests, a simulation of the cash test and its evaluation. The designed model as well as the simulation procedure have been led according to the current Euro NCAP specifications.

This report is a summary of the development of sensor integration for low-cost crash avoidance for over-land commercial trucks. The goal of the project was to build and test a system composed of low-cost commercially available sensors arranged on a truck trailer to monitor the environment around the truck. The system combines the data from each sensor to increase the reliability of the sensor using a probabilistic data fusion approach. A combination of ultrasonic and magnetoresistive sensors was used in this study. In addition, Radar and digital imaging were investigated as reference signals and possible candidates for additional sensor integration. However, the primary focus of this work is the integration of the ultrasonic and magnetoresistive sensors. During the investigation the individual sensors were evaluated for their use in the system. This included communication with vendors and lab and field testing. In addition, the sensors were modeled using an analytical mathematical model to help understand and predict the sensor behavior. Next, an algorithm was developed to fuse the data from the individual sensors. A probabilistic approach was used based on Bayesian filtering with a prediction-correction algorithm. Sensor fusion was implemented using joint a probability algorithm. The output of the system is a prediction of the likelihood of the presence of a vehicle in a given region near the host truck trailer. The algorithm was demonstrated on the fusion of an ultrasonic sensor and a magnetic sensor. Testing was conducted using both a light pickup truck and also with a class 8 truck. Various scenarios were evaluated to determine the system performance. These included vehicles passing the host truck from behind and the host truck passing vehicles. Also scenarios were included to test the system at distinguishing other vehicles from objects that are not vehicles such as sign posts, walls or railroads that could produce electronic signals similar to those of vehicles and confuse the system. The test results indicate that the system was successful at predicting the presence and absence of vehicles and also successful at eliminating false positives from objects that are not vehicles with overall accuracy ranging from 90 to 100% depending on the scenario. Some additional improvements in the performance are expected with future improvements in the algorithm discussed in the report. The report includes a discussion of the mapping of the algorithm output with the implementation of current and future safety and crash avoidance technologies based on the level of confidence of the algorithm output and the seriousness of the impending crash scenario. For example, irreversible countermeasures such as firing an airbag or engaging the brakes should only be initiated if the confidence of the signal is very high, while reversible countermeasures such as warnings to the driver or nearby vehicles can be initiated with a relatively lower confidence. The results indicate that the system shows good potential as a low cost alternative to competing systems which require multiple, high cost sensors. Truck fleet operators will likely adopt technology only if the costs are justified by reduced damage and insurance costs, therefore developing an effective crash avoidance system at a low cost is required for the technology to be adopted on a large scale.