This paper studies a method for active electrohydraulic force compensation in industrial scale high power applications. A valve controlled cylinder moves a mass using the force of inertia to compensate for the reaction forces of an industrial process. Two strategies for force compensation are developed and investigated in a 160 ton clamping unit of an injection moulding machine to significantly reduce the excitation. Results of the different strategies are shown and evaluated. Advantages and drawbacks of the developed electrohydraulic force compensation are discussed.

La régulation ferroviaire sur de vastes zones est un problème complexe. Elle intervient dans la phase opérationnelle de la production. Son rôle consiste à trouver de nouvelles solutions en termes de planification des mouvements de trains suite à l'apparition d'un incident empêchant la réalisation normale du plan de transport préétabli dans les phases amont de la production. La contribution de ce travail s'organise autour de trois axes. Le premier consiste à définir une formalisation exhaustive du système ferroviaire, associé à une représentation plus cohérente (modèle multiniveau). Le deuxième axe s'articule autour de l'étude des modèles mathématiques pour la régulation du trafic ferroviaire: évolutions d'un modèle en temps continu complet (espacements dynamiques), proposition d'un modèle innovant à temps discret et d'un modèle mixte (continu-discret) adossé au modèle multiniveau. Enfin, le dernier axe traite de la mise en oeuvre concrète au niveau industriel, en particulier des gains attendus du couplage avec un outil de simulation.

Les modèles climatiques ont beaucoup progressé pour représenter les nuages. Pourtant la réponse et la rétroaction nuageuse demeure très différente d'un modèle à l'autre, et reste la principale source d'incertitude pour la sensibilité climatique prédite par les modèles de climat, et limite la fiabilité sur les projections du changement climatique dû au forçage anthropique. Il est donc crucial d'améliorer la représentation des processus nuageux dans les modèles climatiques. L'évaluation des nuages nécessite des observations précises. Jusqu'à récemment, des observations de plusieurs aspects fondamentaux des nuages comme la distribution tridimensionnelle des nuages existaient uniquement très grossièrement et obtenus de manière très indirecte par les satellites de télédétection passive (i.e. CERES, ERBE, ScaRab, ISCCP) qui mesurent les flux radiatifs au sommet de l'atmosphère. Les observations A-Train constituent des outils exceptionnels pour caractériser les propriétés nuageuses. L'objet de cette thèse est de tirer profit des observations de l'A-train afin d'évaluer la description des nuages simulée par les modèles climatiques. Nous utilisons le radiomètre CERES pour estimer l'effet radiatif des nuages, les radiomètres PARASOL et MODIS qui mesurent la réflectance, analysée ici comme un proxy de l'épaisseur optique des nuages et le lidar CALIPSO qui fournit des informations précises sur la distribution verticale des nuages. Les données co-localisées et analysées statistiquement constituent une occasion exceptionnelle de contraindre simultanément les propriétés radiatives des nuages et leur distribution tridimensionnelle. Le modèle du climat évalué est le LMDZ ainsi qu'une nouvelle version du modèle en cours de développement, où des nouvelles paramétrisations du bloc couche-limite/convection/nuages est testée. La méthode de comparaison des sorties des modèles climatiques aux grandeurs observées utilise d'une part le simulateur COSP (CFMIP Observation Simulator Package) qui comprend SCOPS, le simulateur lidar et le simulateur PARASOL et d'autre part les jeux des données (CFMIP-OBS) construits pour être compatibles avec les simulateurs. Nous étudions les propriétés nuageuses dans les tropiques par régime de circulation, et en classant les nuages par régions. Une nouvelle méthode a été développée : les observations sont analysées à haute résolution (spatiale et temporelle) au lieu des moyennes mensuelles et saisonnières utilisées habituellement afin de se placer à une échelle aussi proche que possible de celle des processus nuageux. Cette analyse a permis de contraindre les paramétrisations développées pour représenter les nuages et révéler des biais dans les deux versions du LMDZ. Des compensations d'erreurs ont été identifiées (i) sur la distribution verticale des nuages : la couverture nuageuse des nuages hauts et surestimée alors que les nuages bas et moyens sont significativement sous-estimés, (ii) entre la couverture nuageuse et l'épaisseur optique : la couverture nuageuse totale est sous-estimée mais les nuages qui se forment ont une épaisseur optique très élevée ce qui aboutit à une simulation correcte des flux au sommet de l'atmosphère par le modèle.

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Ce travail associe des théories linguistiques et psychologiques pour l'explicitation des liens entre langage et cognition, à partir du concept de confort en train. Des questionnaires ont été élaborés et passés auprès de voyageurs pour recueillir un corpus sur leur ressenti individuel concernant ce concept multisensoriel. Des analyses linguistiques, prenant en compte dans un mouvement récursif, le lexique, la syntaxe, la morphologie et la sémantique, ont été réalisées sur ces données perceptives. Les résultats présentent tout d'abord différents modes d'implication des locuteurs dans leur discours. De plus, à partir des formes relevées en langue et en discours, dans leurs régularités et leurs différences, on formule des inférences sur les catégories cognitives du confort en train. La description de la structuration du concept de confort en train est ensuite effectuée non seulement en regard d'autres concepts, mais également concernant l'organisation interne de ses propriétés, c'est-à-dire que l'on formule des hypothèses sur les relations entre propriétés sensorielles. La méthode employée est tout d'abord globale, avant de porter plus spécifiquement sur l'identification des propriétés d'un concept et de définir sa structuration globale. L'ensemble de ces résultats a alors permis de développer une méthode d'identification des propriétés plus ou moins typiques du confort en train. Non seulement nous avons circonscrit l'articulation entre langue et discours, mais nous avons définit également la nature du rapport au monde réel qu'établissent, chacun à leur manière, les signes linguistiques, les représentations cognitives et les mesures physiques.

Given a closed surface Sg of genus g, a mapping class f in \MCG(Sg) is said to be pseudo-Anosov if it preserves a pair of transverse measured foliations such that one is expanding and the other one is contracting by a number \lambda(f). The number \lambda(f) is called a stretch factor (or dilatation) of f. Thurston showed that a stretch factor is an algebraic integer with degree bounded above by 6g-6. However, little is known about which degrees occur. Using train tracks on surfaces, we explicitly construct pseudo-Anosov maps on Sg with orientable foliations whose stretch factor \lambda has algebraic degree 2g. Moreover, the stretch factor \lambda is a special algebraic number, called Salem number. Using this result, we show that there is a pseudo-Anosov map whose stretch factor has algebraic degree d, for each positive even integer d such that d≤g. Our examples also give a new approach to a conjecture of Penner.

This master thesis represents a life cycle impact assessment of a state of the art electrically driven power train. It is expected to be installed in a diesel engine passenger ferry boat, currently transporting passengers in downtown Stockholm archipelago. The assessment has a comparative character in between the currently operating and the new power train in order to differentiate and recognize which of the two propulsion options is the environmentally preferable choice. The scope of the study is directed towards the thorough examination of both power trains so that it can represent most closely the two specific technological cases. Studied and assessed were the three main life cycle phases of each power train – raw materials acquisition and manufacturing, use phase and end of life phase. The fundament of the study involved creating environmental models for each and every component of the drive trains, the propulsion fuel and energy used, and the services related to waste treatment in the last phase of their functional life. The environmental models were later used to build live cycle inventories that served to derive the respectful impact from the item analyzed. The data used to model the battery electric power train was provided directly from the manufacturer, where the end of life procedures carried out were assumed where possible. The main battery pack for the electric power train was not modeled in terms of  end of life procedures due to insufficiency of information. Almost no generic information was available to model the diesel engine and it was calculated by creating auxiliary simplified cad models. The rest of the data required to achieve an environmental inventory regarding the power train was available from a subcontractor. Both studied options were modeled with allocation approach that includes the avoided production of materials at the waste treatment stage where there was sufficient information to do that. There was none to model the main battery packs avoided production which is a major component of the battery electric system. To model the use phase of the diesel engine power train, research data regarding combustion emissions and waterborne emissions was utilized. A number of electricity mix models were applied to create a sensitivity analysis of the operation phase of the battery electric power train. Chosen for baseline scenarios simulating the use phases of both power trains are use of Nordel market electricity mix and the combustion of low sulfur diesel with five volumetric percent rape methyl ester additive. For the purposes of the assessment eighteen midpoint impact indicators were used to cover the areas of global warming potential, human health and quality of eco systems. The results from the study show that the estimated impact from both power trains is small enough to have almost no influence on the results from the two baseline scenarios. Based on this it was concluded that for future research of similar cases either generic information can be used or a cut-off can be applied. After the assessment, more environmentally favorable was estimated the diesel engine power train because of the large burdens from the battery manufacturing in the battery electric option. Further assessment determined that the diesel engine power train again is less environmentally intensive than the battery electric with the main battery burdens excluded. In the overall life cycle impact assessment both power train showed different results in the different impact categories, which could not place a definitive propulsion option of choice. The conclusions from the analysis are that the diesel engine power train causes higher impact in the categories related to global warming, fossil depletion and in most ecosystems quality indicators. The battery electric version in its base line scenario, on the other hand, expresses higher impact in categories related to human health and in the remaining eco system quality midpoint-scores.

Over 200 railway suicides occur on the British Rail Network (BRN) every year. Research into the physical and psychological effects of this traumatic event on train drivers has been limited, and has focused very little on the mediating influence of personal factors. Kelly’s Personal Construct Psychology (PCP, 1955) was used in the current study to explore the relationship between train drivers’ views of themselves and others, and the psychological impact of witnessing a railway suicide. This was achieved through the use of repertory grid technique. Repertory grid measures of tightness of the overall construct system, level of elaboration of the self and others, construed distances between the self and others, conflict, extremity of ratings, and superordinacy were compared with participants’ scores on a measure of the psychological impact of the event (Impact of Event Scale Revised, IES-R, Weiss & Marmar, 1997). The fifteen participants in the study also completed a background information questionnaire. A content analysis of the constructs used in the repertory grids, and a thematic analysis of a follow up interview with two of the participants was also conducted. The findings indicated that most drivers experienced symptoms suggestive of a significant posttraumatic stress (PTS) reaction following the incident. For many this appeared to be short-lived, but for some the incident had longer lasting effects, and a third of the sample had been given an official diagnosis of Post-Traumatic Stress Disorder (PTSD). Possibly due to the small sample size, many of the correlations did not achieve statistical significance. However, discrepancy between the self and ideal self, and the number of moral constructs employed by participants, were both positively associated with reported levels of psychological distress. The superordinacy of the traumatised construct, and the number of emotional constructs employed by participants, were both negatively associated with reported levels of psychological distress. These findings therefore gave some support to Sewell and Cromwell’s (1990) PCP model of trauma, and to the importance of emotional processing of traumatic events. The thematic analyses added information about the nature of the changes experienced by train drivers following these events, and the impact of contextual factors. The repertory grid technique proved useful in measuring the influence of personal meaning making on the impact of traumatic events. The findings suggest that drivers can best be supported clinically by reducing the discrepancy between their self after the event and their ideal self, increasing their ability to emotionally process their experience, and by giving consideration to issues such as anger and blame. Limitations of the research are presented, as well as suggestions for further research.

This thesis presents a body of work conducted to determine thermal comfort on train journeys. Relatively little research has been conducted on trains in comparison with the vast body of work conducted within building environments. This thesis aimed to expand our knowledge of rail passenger thermal comfort throughout the journey; platform to destination. The train journey was separated into its component parts and analysed by conducting both laboratory and field experiments that either simulated or measured aspects of a train journey. Laboratory experiment 1 examined appropriate methods of data collection during train journeys. Participants (9 males and 9 females) were exposed to a simulated train environment three times and used a different data collection method on each occasion; a paper-based method, a voice recorder or a Personal Digital Assistant (PDA). Results concluded that the three methods can be used interchangeably when recording thermal comfort data. Participants preferred the PDA over the other two methods because they felt it afforded them a level of privacy in addition to blending in with other rail passengers using similar technologies. The second laboratory experiment measured thermal comfort following a change of environment. Participants (12 males and 12 females) were exposed to three environmental conditions (warm, neutral and slightly cool) in a thermal chamber on three separate occasions. The exposure lasted 30 minutes, after which, participants entered a new environment that was the same on each occasion (slightly cool). Results showed that overshoots in sensation (beyond those predicted by the Predicted Mean Vote thermal comfort index PMV) are observed following downward steps (warmer to cooler) in environmental conditions. No overshoots were observed following the upward step (cooler to warmer) in environment, with sensations immediately reflecting the predicted steady-state values. Laboratory experiment 3 (22 males and 26 females) expanded the research conducted in laboratory experiment 2 by exposing participants to greater magnitudes of environmental change. In addition, sensation was measured after this change until steady-state was reached. Participants were exposed to four environmental conditions (cool to warm to neutral to cool or cool to cold to warm to cool) consecutively over a 2 hour period with 30 minutes spent in each location. Results demonstrated similar effects to those observed during laboratory experiment 2 with overshoots observed following downward steps in environmental conditions and none observed in the opposite direction. Sensations demonstrating overshoots gradually increased until steady-state was achieved after approximately 25 minutes. Field experiment 1 (12 males and 32 females) measured thermal comfort while boarding trains. Participants were taken on a short train journey and recorded sensations whilst on the platform and during boarding. Results showed that overshoots may also be observed following step up and step down in environments. It is hypothesised that change in air velocity is influential in this effect. Thermal comfort throughout a train journey was measured in field experiment 2. Participants (16 males and 16 females) reported on thermal comfort on the platform, during boarding and throughout a return train journey from Loughborough to London St Pancras. Results also demonstrated overshoots following upward transients indicating that there are factors in the field that do not occur in laboratory conditions. Subjective parameters reach steady-state after approximately 20 minutes and PMV accurately predicted sensations during the journey. Again, air velocities may have interacted with other variables resulting in the overshoots following upward steps in environmental conditions. Laboratory experiments 2 and 3 resulted in the creation of a model predicting sensation following a change of environment, PMVTRANS. When the model was compared with the field data, it could not accurately predict sensations observed during transients. It also could not predict the sensation overshoots observed following upward transients. A new model is now proposed, NEW PMVTRANS. This model shows greater correlation with actual sensation than PMV; however it does require further validation from field data. Research has shown that PMV is an accurate estimator of sensation within a train carriage and should be used by train designers to optimise the environmental conditions for passengers.

This thesis presents a systematic study of human responses to different motions and strategies of car body tilt control regarding ride comfort, working/reading ability and motion sickness on high-speed tilting trains. Experiments with test subjects were performed in a tilting train on curved track as well as in a moving vehicle simulator. The study is multi-disciplinary, combining knowledge and methods from the fields of railway technology, human factors and vestibular science. The main experiment in a tilting train was performed with about 75 seated test subjects, mainly students from Linköping University, making three test runs. In total, these subjects participated in about 210 individual test rides, each with a duration of about 3 hours. Additional tests on comfort disturbances with pushbutton technique have been reported in the project. The simulator experiments used a total of about 75 subjects, making some 320 test rides each of about 30 minutes duration. Test motions consisted of combinations of horizontal (lateral) acceleration and roll acceleration, together with either roll or horizontal acceleration. Rate of change of horizontal acceleration (jerk) and roll velocity were of the same order of magnitude as in a tilting train environment, but horizontal acceleration alone was about half the magnitude. Horizontal and vertical vibrations from a tilting train were added to the test motions, and train seats and interior train noise were also introduced to create a "train feeling". Test designs and methodology have been developed during the course of the experiments. The test subjects answered questionnaires, four times per test run in the train experiment and each 5 minute in the simulator experiment. The investigated variables were: estimated average ride comfort, estimated ability to work or read, and occurrence of symptoms of motion sickness (dizziness, nausea and not feeling well). Lateral and vertical accelerations together with roll motions were monitored and recorded for later evaluation. Results from the train experiments show that the estimated average ride comfort was about 4 on a 5-degree scale, which indicates “good”. Results also show that a reduced tilt compensation of the lateral acceleration while curving together with a reduced tilt velocity of the car body reduce the provocation of motion sickness. However, a reduction in tilt compensation may produce an increased number of comfort disturbances due to lateral acceleration in the car body. Regression analysis shows that motion doses from roll acceleration may be used to predict the incidence of motion sickness. The simulator experiments show that the primary sources of provocation of nausea and motion sickness are the motion doses from roll and lateral acceleration in the horizontal plane. The study proposes a hypothesis and a model of provocation of motion sickness. It is shown that motion sickness has a time decay, or leakage. A model for this leakage is proposed. The determinative types of motion for provocation of nausea and motion sickness in tilting trains are identified and future tilting train and/or simulator experiments are proposed in order to further investigate their influence. / <p>NR 20140805</p>