L'objectif de ces travaux était de développer et d'évaluer des modèles quantitatifs structure-propriété (QSPR) pour la prédiction des propriétés explosives des composés nitroaromatiques, en vue d'une utilisation dans un cadre règlementaire, en particulier celui du nouveau règlement européen REACH. Différentes approches méthodologiques (régressions multi-linéaires, PCA, PLS, arbres de décision) ont été utilisées pour mettre en place des modèles pour la prédiction de la chaleur de décomposition. Les descripteurs des modèles ont été sélectionnés dans un jeu étendu de plus de 300 descripteurs (constitutionnels, topologiques, géométriques et quantiques). Deux premiers modèles avec des domaines d'applicabilité définis et des pouvoirs prédictifs importants ont été obtenus. Des modèles pour trois autres propriétés explosives (la température de décomposition, les sensibilités à la décharge électrique et à l'impact) ont ensuite été développés, avec des performances similaires voire supérieures aux modèles existants. Enfin, l'analyse des mécanismes réactionnels sous-jacents, menée à l'aide de la DFT, a permis de mettre en évidence la présence de chemins de décomposition spécifiques au sein des composés nitroaromatiques et a ainsi complété l'approche QSPR en termes d'interprétation phénoménologique. Cette étude a donc pris en compte l'intégralité des principes mis en place par l'OCDE pour la validation des modèles QSAR/QSPR dans un usage règlementaire (cible expérimentale, structure du modèle, validation, domaine d'applicabilité et interprétation des mécanismes sous-jacents). Deux modèles prédictifs ont même été développés pour la chaleur de décomposition des composés nitroaromatiques.

Occupational Exposure Limits (OELs) are used as an important regulatory instrument to protect workers’ health from adverse effects of chemical exposures. The main objective of this thesis is to study risk assessment practices in the setting of OEL in order to produce knowledge that will help improve the consistency and transparency of OELs. For the purpose of paper I a database of OELs for a total of 1341 substances was compiled. Of these, only 25 substances have OELs from all 18 included organisations while more than one third of the substances are only regulated by one organisation alone. The average level of OELs differs substantially between organisations; the US OSHA exposure limits are (on average) nearly 40 % higher than those of Poland. In paper II six EU member states’ OELs are compared to the European Commission’s OELs. Also within Europe there is a large difference concerning the average level of OELs (35%). The average level of lists tends to decrease over time, although there are exceptions to this. There are also indications that the exposure limits of EU member states are converging towards the European Commission’s OELs. The work presented in paper III identifies steps in the risk assessment that could account for the large differences in OELs for 14 different substances. Differences in the identification of the critical effect could explain the different level of the OELs for half of the substances. But the age of the data review could not account for all the differences in data selection, only one fifth of the documents referred to all available key studies. Also the evaluation of the key studies varied significantly. The aim of paper IV was to investigate how the Scientific Committee on Occupational Exposure Limits (SCOEL) of the European Commission uses assessment factors when proposing health-based indicative OELs. For only one third of the investigated OELs were explicit assessment factors given. On average the safety margin of the recommendations was 2.1 higher when an explicit assessment factor had been used. It is recommended that the SCOEL develop and adhere to a more articulate framework on the use of assessment factors. Paper V focuses on the Derived No-Effect Levels (DNELs) which are to be calculated under the new European Union REACH legislation. It is a comparison of the safety margins of 88 SCOEL recommendations with those of the corresponding worker-DNELs, derived according to the default approach as described in the REACH guidance document. Overall, the REACH safety margins were approximately six times higher than those derived from the SCOEL documentations but varied widely with REACH/SCOEL safety margin ratios ranging by two orders of magnitude, from 0.3 to 58. / QC 20110215

The demand for energy from developed and developing economies of the world is driving the search for energy resources to more challenging environments. The exploration and exploitation of hydrocarbons now requires the drillbit to hit pay zones from drillships or platforms that are located on water surfaces below which is, possibly, in excess of ten thousand feet of water above the sea bed. From Brazil, to the Gulf of Mexico and the Gulf of Guinea on the western coast of Africa, hitherto unfamiliar, but now common, concepts in the drilling parlance such as ultra-deep drilling (UDD), ultraextended- reach drilling (uERD) and slimhole drilling, are employed to reach and produce reservoirs which a few decades ago would seem technologically impossible to produce. This is expected to exert tremendous demands on the physical and mechanical properties of the drillstring components. Limiting factors for reaching and producing oil and gas resources hidden very deep in the subsurface are both the capacity of the drilling rig to support the weight of the drillstring, which in some instances can be several kilometres long, and the bending, tensile and impact stresses the string has to withstand in well trajectories that are getting both longer and more tortuous. Associated with this increased well depths and complex well trajectories is the prohibitive cost penalty of a failed drillstring. The in-service failure of drillstrings has always been an issue in the industry long before the wells become this deep and complex. The global oil and gas industry estimates the cost of string failure to be in excess of quarter of a billion dollars annually. Researchers are continuously looking for ways to design against string failure and improve the level of confidence in drillstrings. Defect-tolerant design, tooljoint geometry modification and surface coldworking are just a few of the ideas that have gained mileage in this effort. Others that are now in consideration are the use of nonconventional materials such as aluminium and titanium alloys for drillstring components. More novel, still, is the use of a combination of two materials - one ‘softer’ than the other to form a hybrid string of two materials of unequal moduli of elasticity. This is done to make the string lighter, reduce stress concentration factor at the connections and place fatigue resistant materials in areas of high well bore curvature.In this work a computational technique in the form of two-dimensional finite element analysis is used to develop a robust model of a drillstring connection and to analyse the stresses on the model of a threaded connection of standard drillstring tooljoint made from alloy steel. Further comparative analyses were undertaken on models of drillstrings made from a newly developed drillstring material for ultra-deep drilling, the UD-165, aluminium and titanium alloys and, finally, on hybrid drillstrings made from two different materials of unequal moduli of elasticity. The aim is not only to develop and validate a better method of computational drillstring analysis but also to use the model to investigate and suggest areas of optimisation that will benefit industry especially in the areas hybrid strings.

Tellurium is one of the rarest metals in the earth’s crust. Increased demand for cadmium telluride photovoltaic cells along with an opaque pricing and quantity-reporting system, have recently caused high price volatility and a speculative bubble in the tellurium market, resulting in overstocking and depressed prices. In a longer perspective this may be a threat to cadmium telluride photovoltaics as a power-generating technology. This master thesis compares how actors may perceive news innovation in the opaque tellurium market compared to the more transparent molybdenum market. A quantitative analysis of industry news reporting on the two metals, combined with a SVAR impulse response analysis, helps me determine which actors and factors exert most influence on spot market prices. In the opaque tellurium market, relatively unreliable proxies of supply and demand are most frequent in the news reporting while having a big impact on prices, whereas the transparent molybdenum market uses more reliable variables – such as futures prices – and transparent supply information, whilst also relying on a frequent stream of dependable proxies to scope market sentiments. My findings lead me to recommend policy makers to implement measures to increase market transparency, which may be accomplished by extending the data-sharing regime of the REACH database to minor metal markets. Attempting to limit speculation in minor metal markets is perhaps too blunt a tool to fix an inherent problem of a free exchange-pricing mechanism. / Tellur är en av de mest sällsynta metallerna på Jorden. Ökad efterfrågan av kadmiumtelluridsolpaneler har nyligen orsakat stor volatilitet på tellurmarknaden. Ett opakt prissättnings-och kvantitetsrapporteringssystem har bidragit till att en prisbubbla bildats och spruckit, vilket resulterat i att marknadsaktörer köpt på sig stora lager till höga priser som de sedan inte kunnat sälja vidare. I ett längre perspektiv kan detta innebära begränsningar vid tillverkning av solcellsteknologi baserad på kadmiumtellurid, då ett volatilt pris kan göra nya tellurgruvprojekt alltför riskabla. Denna masteruppsats jämför hur en typisk marknadsaktör kan reagera på prisinnovationer i den opaka tellurmarkanden och den mer transparenta molybdenmarknaden. Metoden består av en kvantitativ analys av facknyheter rörande de två metallerna, varifrån variabler väljs till en SVAR modell med impuls-responsanalys. Urvalet av variabler är få och volatila på den opaka tellurmarknaden, medan den mer transparenta molybdenmarknaden har ett större utbud av variabler som kännetecknas av god transparens och relativ förutsägbarhet. Mina slutsatser leder mig till att rekommendera beslutsfattare att vidta åtgärder för att öka tellurmarknadens transparens genom EU-samarbetet, förslagsvis genom att göra anonymiserad data från REACH databasen tillgänglig för allmänheten. Samtidigt avråder jag från åtgärder som syftar till att minska spekulation, då implementering av en sådan policy kan bli både dyr och komplicerad.

Volumes of trade between the European Union and China have increased tremendously over the last decades, with the EU becoming China`s largest trading partner. Among the academic world there are serious concerns about the impacts of trade on national environmental regulation setting. There is fear that international trade will not only put advanced nations under strong competitive pressure to lower their environmental standards in order to stay competitive (race to the bottom) but also provide developing nations no incentives to strengthen their environmental protection measures as this would carry costs and reduce their global competitiveness (stuck at the bottom). In contrast to that believe, some scholars, such as David Vogel, argue that engaging in international trade can ¡V under certain assumptions ¡V result in tighter national regulation setting among trading partners (trading-up). This study sets out to analyze the linkage of trade and environmental standards between two major trading powers ¡V the EU and China. China`s integration with the world economy has spurred concerns among environmentalists as it was feared that the country`s national environmental regulatory system will be kept at low levels due to competitiveness considerations. However, China, the opposite can be observed. The EU has adopted strict environmental directives in several areas, and China has upgraded its environmental regulatory system. This study aims to find answers to the question if in the case of trade between the EU and China a situation of trading-up can be identified. In order to bring in domestic as well as international developments, the study applies a two-level games approach. The research is based on recent environmental directives that have been adopted by the EU. A selection of three directives forms the basis of the case studies: the Restriction of Hazardous Substances (RoHS), car emissions standards, and the Registration, Evaluation, Authorization, and Restriction of Chemicals (REACH). The study provides insights into how China is affected by these external regulations, how it responded to them and how it tries to utilize them to boost its economic development and enhance the quality of its environment. As the study reveals, European environmental directives have positive impacts on China`s national environmental regulatory setting processes, since the EU regulations not only raise the awareness of the issue among China`s policy makers and public interest groups but they also called for responses from affected domestic constituents. The external regulations raised the stakes of numerous domestic actors which then had to decide how to react adequately. All in all, the study concludes that EU environmental directives have worked in favor of stricter regulation setting in China.

As control systems become more integrated with high-end engineering systems as well as consumer products, they are expected to achieve specifications that may include logic rules, safety constraints, startup procedures, and so forth. Control design for such complex specifications is a relatively unexplored research area. One possible design approach is based on partitioning the state space into polytopic regions, and then formulating a certain control problem on each polytope, with the intention that the set of all controllers so obtained would collectively achieve the specification. The control problem which must be solved for each polytope is called the reach control problem, and it has been identified as turnkey to the further development of this approach. The reach control problem (RCP) is to find a state feedback to make the closed-loop trajectories of an affine (or linear) control system defined on a polytope reach and exit a prescribed facet of the polytope in finite time. This dissertation studies a number of aspects of the reach control problem, and it uses tools from convex analysis, nonsmooth analysis, and computational geometry for this study. The dissertation has three main themes. First, we formulate and solve a variant of RCP in which trajectories exit the polytope in a monotonic sense; this provides a triangulation-independent solution of RCP. Second, we develop a Lyapunov-like theory for verifying if RCP is solved using a given candidate controller. This involves the introduction of the notion of generalized flow functions, a LaSalle Principle for RCP, and several converse theorems on existence of generalized flow functions. Third, we study the relationship between affine feedbacks and continuous state feedbacks for RCP on simplices. Although the two feedback classes have been shown to be equivalent under an assumption on the triangulation of the state space, we show by a counterexample that the equivalence is no longer true under arbitrary triangulations. Then we provide for single-input systems a constructive method for the synthesis of multi-affine feedbacks for RCP on simplices.

As control systems become more integrated with high-end engineering systems as well as consumer products, they are expected to achieve specifications that may include logic rules, safety constraints, startup procedures, and so forth. Control design for such complex specifications is a relatively unexplored research area. One possible design approach is based on partitioning the state space into polytopic regions, and then formulating a certain control problem on each polytope, with the intention that the set of all controllers so obtained would collectively achieve the specification. The control problem which must be solved for each polytope is called the reach control problem, and it has been identified as turnkey to the further development of this approach. The reach control problem (RCP) is to find a state feedback to make the closed-loop trajectories of an affine (or linear) control system defined on a polytope reach and exit a prescribed facet of the polytope in finite time. This dissertation studies a number of aspects of the reach control problem, and it uses tools from convex analysis, nonsmooth analysis, and computational geometry for this study. The dissertation has three main themes. First, we formulate and solve a variant of RCP in which trajectories exit the polytope in a monotonic sense; this provides a triangulation-independent solution of RCP. Second, we develop a Lyapunov-like theory for verifying if RCP is solved using a given candidate controller. This involves the introduction of the notion of generalized flow functions, a LaSalle Principle for RCP, and several converse theorems on existence of generalized flow functions. Third, we study the relationship between affine feedbacks and continuous state feedbacks for RCP on simplices. Although the two feedback classes have been shown to be equivalent under an assumption on the triangulation of the state space, we show by a counterexample that the equivalence is no longer true under arbitrary triangulations. Then we provide for single-input systems a constructive method for the synthesis of multi-affine feedbacks for RCP on simplices.

L'hétérogénéité inter-patients des altérations motrices consécutives aux lésions cérébrales rend nécessaire le besoin d'individualiser la prise en charge du patient après AVC. Afin d'apporter une thérapie adaptée aux besoins du patient au moment opportun, il est nécessaire de prendre en compte plusieurs considérations théoriques afin de comprendre comment la rééducation influence la plasticité cérébrale. La récupération motrice est un phénomène complexe et non-linéaire, et identifier ses composantes caractéristiques est délicat. Au travers d'une étude observationnelle, nous avons investigué la récupération de la fonction motrice en condition unimanuelle (membre non-parétique, parétique) et bimanuelle chez des patients cérébro-lésés en phase subaigüe, sans interférer sur leur programme de rééducation classique. Nous avons d'abord validé l'analyse cinématique pour l'évaluation motrice des mouvements d'atteinte d'objets après AVC, en complément des tests cliniques. L'analyse cinématique permet de fournir des indicateurs de la récupération en temps réel de manière plus sensible que les échelles cliniques. En condition unimanuelle, la récupération du membre non-parétique progresse avant de se stabiliser après 9-10 semaines après AVC. En condition bimanuelle, la dynamique de récupération des coordinations bimanuelles change 6 semaines après AVC. Ces périodes pourraient être des fenêtres temporelles clés à prendre en compte en établissant des protocoles de rééducation. L'identification complète et précise de ces patterns naturels de récupération après AVC pourrait permettre de mieux comprendre les réseaux nerveux spécifiques qui sous-tendent les altérations du membre supérieur. A partir de ces indications cliniques prometteuses, proposer une rééducation adaptée au patient et au meilleur moment devient le challenge des travaux futurs. / Poststroke characteristics vary significantly between patients and over time, necessitating the introduction of individualized care. To provide to patients an appropriate and timely therapy, theoretical considerations must be taken into account to understand how a therapy may influence underlying neuroplasticity. Motor recovery is a nonlinear and complex function of time, and identifying its representative features remains intricate. Through observational analysis, we investigated in this thesis the time-related changes in unimanual (nonparetic, paretic upper-limb) and bimanual motor function in subacute poststroke patients, without interfering with standard rehabilitation. Overall, our results firstly validated the relevance of kinematics to assess recovery of reaching movements following stroke, in complement to clinical scores. Kinematics provides accurate real-time indicators of patients' recovery in a more sensitive way to current clinical scales. In unimanual reaching, motor function of nonparetic upper-limb recovered and then leveled off 9-10 weeks poststroke. In bimanual reaching, the dynamic of the recovery pattern of between-hands coordination changed after 6 weeks poststroke. These time-windows might be key periods to consider into designing rehabilitation protocols. Our results contribute to a better understanding of the natural pattern of motor recovery poststroke and could be of interest to understand specific neural network underlying upper-limb impairment. From these promising therapeutic guidelines, next challenge in future research includes tailoring rehabilitation training to patients at the most opportune time.

Bakgrunden till studien är att det finns begränsad forskning inom det barn- och ungdomsvetenskapliga forskningsfältet om interaktionen mellan ungdomar och professionella i det offentliga rummet. Tidigare forskning inom området har varit inriktad på berättelser från informanter, men få studier har undersökt fenomenet utifrån en etnografisk utgångspunkt. Kunskap om hur interaktionen mellan ungdomar och fältsekreterare utvecklas i det offentliga rummet för att uppnå en legitimitet för fältsekreterare till fältet är mycket begränsad. Att belysa ungdomars agentskap i interaktionen har varit vägledande eftersom tidigare forskning inom fältarbete har varit utifrån de professionellas utgångspunkt. Syftet med studien är att beskriva, analysera och tolka hur fältsekreterare interagerar med ungdomar i det offentliga rummet. Genom en etnografisk ansats skildras (observeras), inte bara det som sägs, utan även det som görs i interaktionen. Följande forskningsfrågor har undersökts: Hur skapar fältsekreterare legitimitet till fältet? Vilka strategier använder fältsekreterare för att skapa kontakt med ungdomar och samtidigt tillvarata ungas agentskap och vilka egenskaper upplever ungdomar är viktiga att ha som fältsekreterare? Studien bygger på deltagande observationer, och på informella samtal med ungdomar, i en utvald kommun avseende fältsekreterares legitimitet till fältet. Genom deltagande observation kan forskaren befinna sig i det offentliga rummet med fältsekreterare och ungdomar och observera det som verkligen händer i interaktionen. Genom tolkning kan forskaren lyckas fånga den subjektiva innebörden av social handling. Sammantaget gjordes tretton fältanteckningar avseende observationerna med två fältsekreterare samt informella samtal med åtta ungdomar, tre killar och fem flickor. Omfattningen av dessa fältanteckningar varierade mellan några preliminära noteringar såsom stödord och mentala noteringar, för att senare utgöra fullständiga fältanteckningar i slutet av dagen. Tolkningsprocessen genom den hermeutiska cirkeln har varit till hjälp för en erfarenhetsnära tolkning av fältsekreterares sätt att handla. Resultatet visar att legitimitetskapande till fältet förutsätter att professionella genom ett socialpedagogiskt förhållningssätt agerar i det offentliga rummet och interagerar med ungdomarna i den kontexten dessa befinner sig i. Genom att ha kunskap om ungdomar, förmedlar fältsekreterare tillit och trygghet. Genom att synas i det offentliga rummet utövar fältsekreterare en form av makt, vilken innefattar såväl kontrollerande som hjälpande dimensioner. Fältsekreterarnas strategier för att skapa legitimitet förutsätter ofta förtroendefulla relationer till ungdomar. / The background of the study is that there is limited research in the child- and youth research field, on the interaction between youth and professionals in the public space. Previous research in the field have been focused on stories from informants, but few studies have been based on an ethnographic approach. Observing how the interaction between young people and out-reach workers develops in public spaces to achieve legitimacy to the field is very limited. Promoting youth agency in the interaction has been guiding in this study, as previous fieldwork research has been based on the professional's point of view. The purpose of the study is to describe, analyze and interpret how out-reach workers interact with young people in the public space. Through an ethnographic study show, not only what is said but also observe what is happening in the interaction. The relevant issues for this study are the following ones: How do out-reach workers create legitimacy in the field? What strategies are out-reach workers using to make contact with young people while at the same time preserving their agency? And, from a young person’s perspective, which characteristics are important to have as an out-reach worker? The study is based on participative observations and informal conversations with young people and outreach worker in a selected municipality. Through participative observation we can find ourselves in public spaces with outreach workers and young people and observe what is really happening in the interaction between them. By interpretation, the researcher is able to capture the subjective importance of social action. All in all, thirteen field notes were made. The scope of these field notes varied between some preliminary notes such as support words and mental notes, to later complete full field notes at the end of the day. The interpreting process through the hermeneutic circle has been helpful for the experience-near interpretation of the individual's way of thinking, but also the way of acting. The result shows that the creation of legitimacy in the field requires that professionals through a social pedagogical approach act in public space and interact with the young people in the context in which they are. By having knowledge of young people, the outreach worker convey confidence and security. By appearing in the public space, outreach worker exercise a form of power, which includes both controlling and helping dimensions. The outreach workers strategies for creating legitimacy often require trustful relationships with young people.

The Regulation No. 1907/2006 on registration, evaluation, authorisation and restriction of chemical substances and on establishment of the European Chemicals Agency, the so-called REACH (Registration, Evaluation, Authorisation and Restriction of Chemical substances) came into effect on 1 June 2007. The purpose of the Regulation has been to ensure safe functioning of the market with chemical substances and preparations and protection of human health and environment against effects of toxic substances. After a complete implementation of the Regulation the only substances and preparations produced and used in the European Union will be those with known toxicological properties, including data about their impact on the health of future generations. The thesis focuses on the description of the REACH Regulation, schedule of its implementation and its potential benefits for the improved effectiveness of rescue and liquidation works performed by members of the Integrated Rescue Service (IZS). Due to very limited sources available at the early stage of REACH implementation, the method selected for the work was consultations with experts directly specializing in the REACH legislation, managers of pharmaceutical or chemical companies managing work with toxic substances and IZS members. Expert opinions have been collected about the legislation process and about the situation in the industry. The Fire Rescue Service uses databases Medis Alarm, Rozex Alarm, TEREX and Trins for planning and implementation of its interventions. In 2013 {--} 2020 I expect bigger quantities of data obtained within the REACH framework to be transmitted into those databases; in that period it will be necessary for the IZS members to become familiar with REACH and with the implemented methods of transmission of toxicological data and to be able to critically evaluate available databases when planning an intervention under conditions of a potential threat posed by toxic substances to the health of IZS members, to the population in the surroundings and to the environment. I recommend to start teaching REACH as a topic at specialized schools so that future graduates are familiar with REACH at least theoretically.