<p>Three of the most important factors with regards to wireless multi-hop networks, namely reachability, energy consumption and network stability are considered in our transmitter macrodiversity supported broadcasting routing algorithms. Broadcasting applications are not only used to send routing table, queries, programming logic, any specific request etc. to all the nodes from access point but are also capable of playing a vital role in wireless TV distributions and visual sensor networks. All the algorithms are simulated in the MATLAB environment in which the nodes are random and are battery driven on a multi-hop randomized topology. Four new single frequency network (SFN) based algorithms (SFN-A, SFN-B, SFN-C and SFN-D) are formed in order to work over multi-hopping and where three of the algorithms SFN-A, SFN-B and SFN-D bear more or less the same amount of reachability. These three algorithms are able to reach more than 90% of reachability in only Tx power -8dBm whereas non-SFN requires -4dBm and SFN-C requires -2dBm and, in addition can achieve a maximum of 29 percentage points more reachability than the non-SFN algorithm. However, the best algorithm SFN-D consumes a maximum of 58.76% less energy than the SFN-A and a maximum of 14.28% less energy than the SFN-B. The SFN-D algorithm achieves a maximum 3.43 dB diversity gain together with the maximum 37.33% energy consumption gain in comparison to the non-SFN algorithm.</p>

Physical habitat for instream biota derives from a combination of stream system structural and hydraulic phenomena. Consequently, the quantity and quality of physical habitat is dynamic both over time and in space along the river, laterally, longitudinally and vertically. Its characterization through stream assessment and classification leads to a better understanding of factors that determine and limit habitat extent and quality. This thesis investigates the effects of space and time on nearshore aquatic habitat in the gravel reach of Fraser River, British Columbia by employing a large river, stage-adaptive habitat classification system. The distribution and abundance of habitat are spatially quantified at the reach scale (32 km), and temporally quantified through a period of about 60 years at several adjacent gravel bars (7 km), and at approximately 500 m3 s-1 increments in discharge during the declining limb of the flood hydrograph at two well-developed gravel bars. Of the ten habitat types evaluated, the bar edge habitat type is most abundant by length and number of units. However, its relative importance is reduced when weighted by fish-habitat association characteristics. Preferred habitat types (channel nook, eddy pool and open nook) are frequent and available to aquatic organisms, and most common at well-developed bars and in zones of equilibrium long-term sedimentation. Preferred habitat was at a maximum 30 years ago when major new bars developed and the thalweg shifted, effectively increasing the amount of bar shoreline and nearshore habitat. This increase is due to substantial change in river planform morphology following a 30-year period of large annual floods. However, amounts of habitat did not increase exclusively during periods of higher than average flows, or decrease exclusively during periods of lower than average flows. Instead, habitat abundance response to flow may occur with a two- or three-year lag. Short term changes in stage are critical to amount of preferred habitat. Optimal discharge for maximum preferred habitat vailability is in the range of approximately 2500 m3 s-1 to 4000 m3 s-1, which approximates long term mean flow. As flow increases, the proportion of preferred habitat compared with total bar shoreline decreases. Comparison with the 2006 flow duration curve shows that 15 – 30 % of discharges are optimal for maximum fish density and biomass. These discharges occurred during April 27 to May 17 and July 14 to August 7, 2006.

Metallic robotic arms, or manipulators, currently dominate automated industrial operations, but due to their intrinsic weight, have limited usefulness for large-scale applications in terms of precision, speed, and repeatability. This thesis focuses on exploring the feasibility of using polymeric composite materials for the construction of long-reach robotic arms. Different manipulator layouts were investigated and an ideal design was selected for a robotic arm that has a 5 [m] reach, 50 [kg] payload, and is intended to operate on large objects with complex curvature. The cross-sectional geometry of the links of the arm were analyzed for optimal stiffness- and strength-to-weight ratios that are capable of preserving high precision and repeatability under time-dependent external excitations. The results lead to a novel multi-segment link design and method of production. A proof-of-concept prototype of a two degrees-of-freedom (2-DOF) robotic arm with a reach of 1.75 [m] was developed. Both static and repeatability testing were performed for verification. The results indicated that the prototype robot main-arm constructed of carbon fiber-epoxy composite material provides good stiffness-to-weight and strength-to-weight ratios. Finite element analysis (FEA) was performed on a 3-D computer model of the arm. Successful verification led to the use of the 3-D model to define the dimensions of an industrial-sized robotic arm. The results obtained indicate high stiffness and minimal deflection while achieving a significant weight reduction when compared to commercial arms of the same size and capability.

Syftet med studien har varit att undersöka samverkan mellan fältsekreterare, polis och socialsekreterare samt vilken funktion fältsekreterarna fyller för polis och socialsekreterare i deras ungdomsinriktade arbete. Uppsatsen har sin utgångspunkt i projektet Lokal operativ samverkan i stadsdelarna Gottsunda/Valsätra i Uppsala. Studien rör sig inom det komplexa område som samverkan innebär. Skapar fältsekreterarna nya förutsättningar för hur yrkesgrupperna tillsammans kan arbeta mot ett gemensamt mål? Tidigare forskning har visat att samverkan mellan socialtjänst och polis är beroende av en gemensam problemdefinition och samsyn. Fältsekreterarna verkar i en mittenposition där de förväntas arbeta både utifrån socialtjänstens formulerade önskemål och utifrån ungdomens behov. Fältarbetet kretsar ofta kring att skapa relationer till en grupp som har en negativ bild av myndigheter och att förmå dessa att ta emot samhällets stöd. De teoretiska perspektiv som appliceras för att förstå och tolka samverkan och de interaktioner som sker inom den är systemteori och symbolisk interaktionism. Det är en kvalitativ studie som har genomförts i form utav semi- strukturerade intervjuer. Sex personer har intervjuats; fältsekreterare, polis och socialsekreterare. Intervjuerna analyserades genom en innehållanalys, där skillnader och likheter mellan uttalandena kartlades. Resultatet bekräftar en del av den tidigare forskningen. Respondenterna i studien lyfter fram vikten av en gemensam samsyn. I en samverkan är det viktigt att samverkansparterna fyller skilda funktioner och kompletterar varandra. Respondenterna beskriver att de har skilda perspektiv som kan gynna samverkan. De verifierar att det finns en myndighetsskepsis hos målgruppen, därför strävar fältsekreterarna efter att skapa ett förtroende hos ungdomarna. Fältsekreterarna fungerar för polis och socialsekreterare som en förebyggande aktör. De är myndigheternas ögon utåt. De tre undersökta yrkesgrupperna kan betraktas som ett system, där de fyller olika funktioner men tillsammans arbetar de mot ett gemensamt mål. Samverkan i sig bidrar till en ökad förståelse för varandras arbeten. Den slutsats som kan dras av studien är att det i samverkan är viktigt att ta tillvara på varandras kompetenser och funktioner. Genom att göra detta kan man på bästa sätt möta omvärldens behov. Fältsekreterarna är ytterligare en aktör som verkar i området, de kan skapa en bredare kunskap hos polis och socialsekreterare. / The aim of this study has been to illustrate the collaboration between out-reach workers, police and social workers. The purpose of the study has also been to explore the impact out- reach workers has on the work of the police and social services. Out- reach workers are social workers whose main work is to locate and help youth in their own environment. The basis has been a project in Uppsala, Lokal operativ samverkan. By adding the out- reach workers to the already existing collaboration between police and social workers the conditions changes. Research on the subject has shown that the collaboration is dependent on a joint vision. Out- reach workers exist in the middle, they must meet expectations from the social workers but their main task is to work for the youth in the community. They often meet youth in vulnerable situations. The work includes creating a functional relationship between the youths and the societies agencies. The applied theories have been system theory and symbolic interactionism. The study has a qualitative approach. Six persons have been interviewed using semi-structured interviews, including police, out- reach workers and social workers. Over all the result confirms earlier research on the subject. An agreement about the task is essential for the participants. It’s important to have different roles and to complement each other, to appreciate the different functions. The participants describe how different perspectives further the collaboration. The out- reach workers aim to strengthen the relationship between the youth and the authorities. They function as a preventive and observing agent in the community. The police, the social workers and the out- reach workers function as a system that works against a common vision, but with different tasks. Finally the study shows that it’s vital to take advantage and to esteem the differences in assignments in the collaboration. By doing this the agents can meet the need of the community. The out- reach workers can broaden the knowledge about the youths in the collaboration with the police and the social workers.

This thesis studies the Reach Control Problem (RCP) for affine systems defined on simplices. The thesis focuses on cases when it is known that the problem is not solvable by continuous state feedback. Previous work has proposed (discontinuous) piecewise affine feedback to resolve the gap between solvability by open-loop controls and solvability by feedbacks. The first results on solvability by time-varying feedback are presented. Time-varying feedback has the advantage to be more robust to measurement errors circumventing problems of discontinuous controllers. The results are theoretically appealing in light of the strong analogies with the theory of stabilization for linear control systems. The method is shown to solve RCP for all cases in the literature where continuous state feedback fails, provided it is solvable by open loop control. Textbook examples are provided. The motivation for studying RCP and its relevance to complex control specifications is illustrated using a material transfer system.

<p>For the majority of the estimated 70,000 industrial chemical substances available on the European market today there is not enough information to enable a reasonably complete assessment of the risks that they might pose to man and the environment. Any strategy for the generation of additional data for these substances should aim at making testing as efficient as possible taking into account environmental and health protection, time, monetary cost and animal welfare. To achieve this, appropriate priority setting rules are needed.</p><p>The main criterion currently used for regulatory priority setting for testing of industrial chemicals is production volume; the higher the production volume, the more information is required. This was also the main criterion in the former legislation, preceding REACH (Registration, Evaluation and Authorisation of Chemicals). The aim of this thesis is to evaluate other priority setting criteria and their implications for risk management, in particular classification and labelling.</p><p>The first paper in this thesis includes a study of the<i> efficiency ratio</i> for some of the tests required for the notification of new substances, i.e. the ratio between the likelihood that the test will lead to a classification, and the monetary cost of performing the test. The efficiency ratio was determined for the standard tests for acute oral toxicity, irritation, sensitisation and subacute toxicity using data from 1409 new chemicals notified in Europe between 1994 and 2004. The results of this investigation suggest that, given limited resources for testing, it is more efficient to perform acute toxicity tests on a larger number of substances rather than to perform additional subacute toxicity studies on the substances already tested for acute toxicity.</p><p>The second paper included in this thesis, reports the results from a comparative study of the bioaccumulating properties of substances being (a) classified as carcinogenic, mutagenic and/or toxic to reproduction (CMR-substances), or (b) classified as acutely toxic or (c) unclassified. The purpose of this investigation was to evaluate potential consequences of prioritising bioaccumulating chemicals for evaluation and testing, as this is one of the strategies prescribed in REACH. The results of this study suggest that bioaccumulating substances are neither over- nor underrepresented among the CMR-substances. This result lends support to the use of the bioconcentration factor for priority setting.</p><p>The studies reported in this thesis utilize existing data on classification of substances as an indicator of the outcome of the risk assessment process, relating priority setting methods to the risk management measures that they give rise to. To the best of my knowledge there are still only very few studies published that address the issue of priority setting in chemicals control using this approach, and in my view there is need for more studies of priority setting methods and a further development of priority setting strategies that are science-based.</p>

Ftalater är ett ämne som har till syfte att verka mjukgörande i plast. Ftalater finns i flera material och produkter i vår omgivning t ex i leksaker, elektronik, textilier och i inredningsmaterial. De problem som uppkommer i samband med användandet av ftalater i produkter är att ftalaterna inte är kovalent bundna till sitt material och därmed kan dessa frigöras ut i luft och damm. Flera ftalater är klassade som hormonstörande ämnen och kan påverka flera viktiga funktioner i kroppen. Barn är en extra känslig grupp då flera av deras organ ännu inte är färdigutvecklade och är beroende av ett fungerande endokrint system.   Barn spenderar en stor del av sin vardag på förskolan och det ställer krav på deras inomhusmiljö. Studier visar på att koncentrationerna av ftalater är 2-4 gånger så hög i förskolans inomhusmiljö som i hemmiljön. Med tanke på att barn har flera organsystem under utveckling är det viktigt att fasa ut onödiga källor för exponering av ftalater.   Arbetets syfte är att kartlägga ftalater i inomhusmiljön på förskolor i Växjö kommun och att undersöka pedagogers medvetenhet kring ämnet. Arbetet utgår från tidigare vetenskapliga artiklar och en enkätundersökning som personal på 46 förskolor i Växjö kommun har besvarat.   Studier som undersökt inomhusmiljöer visar på att det förekommer höga koncentrationer av ftalater som är begränsade enligt REACH-förordningen. Då ftalater finns i flera produkter blir det många olika exponeringskällor och det gör det viktigt att fasa ut onödiga källor för att minska koncentrationen av ftalater i luft och damm. De mest intressanta resultat som kommit fram via enkätundersökningen är att det förekommer plastgolv i de flesta lokaler, elektronik finns i de rum där barnen spenderar mest tid och att barn använder “vuxna leksaker” såsom äldre elektronik, väskor och skor. Ett resultat som visar att barn lever i en allt mer vuxen miljö med produkter som är avsedda för vuxna. Sådana produkter täcks inte in av de begränsningar som REACH-förordningen skapat och täcks inte heller av de nya leksaksdirektiven.   Förskolepedagogerna uppger sig vara medvetna om ämnet ftalater men ändå visar undersökningen att det finns en rad olika brister i kunskap. Det är därför viktigt att öka kunskapen och medvetenheten kring ämnet för att på så sätt fasa ut onödiga källor för exponering av ftalater.

Physical habitat for instream biota derives from a combination of stream system structural and hydraulic phenomena. Consequently, the quantity and quality of physical habitat is dynamic both over time and in space along the river, laterally, longitudinally and vertically. Its characterization through stream assessment and classification leads to a better understanding of factors that determine and limit habitat extent and quality. This thesis investigates the effects of space and time on nearshore aquatic habitat in the gravel reach of Fraser River, British Columbia by employing a large river, stage-adaptive habitat classification system. The distribution and abundance of habitat are spatially quantified at the reach scale (32 km), and temporally quantified through a period of about 60 years at several adjacent gravel bars (7 km), and at approximately 500 m3 s-1 increments in discharge during the declining limb of the flood hydrograph at two well-developed gravel bars. Of the ten habitat types evaluated, the bar edge habitat type is most abundant by length and number of units. However, its relative importance is reduced when weighted by fish-habitat association characteristics. Preferred habitat types (channel nook, eddy pool and open nook) are frequent and available to aquatic organisms, and most common at well-developed bars and in zones of equilibrium long-term sedimentation. Preferred habitat was at a maximum 30 years ago when major new bars developed and the thalweg shifted, effectively increasing the amount of bar shoreline and nearshore habitat. This increase is due to substantial change in river planform morphology following a 30-year period of large annual floods. However, amounts of habitat did not increase exclusively during periods of higher than average flows, or decrease exclusively during periods of lower than average flows. Instead, habitat abundance response to flow may occur with a two- or three-year lag. Short term changes in stage are critical to amount of preferred habitat. Optimal discharge for maximum preferred habitat vailability is in the range of approximately 2500 m3 s-1 to 4000 m3 s-1, which approximates long term mean flow. As flow increases, the proportion of preferred habitat compared with total bar shoreline decreases. Comparison with the 2006 flow duration curve shows that 15 – 30 % of discharges are optimal for maximum fish density and biomass. These discharges occurred during April 27 to May 17 and July 14 to August 7, 2006.

The demand of electric power has rapidly increased in China along with the financial development. High pollution rates have pushed the development towards more renewable energy generating alternatives. In recent years larger investments of hydropower- generated electricity have been to satisfy the increased demand. Hydropower can cause non-energy related problems when implemented in a large scale. In this project the Nanjing Reach of Yangtze River was investigated through a hydrodynamic and sediment transport perspective. Nanjing Reach consists of two river branches and the upstream construction of the Three Gorges Dam has caused an imbalance of sediment composition that leads to an increasing difference of the diversion ratio between the branches. This is causing a problematic navigational situation for larger vessels along the north branch. In this project non-submerged water diverting dykes were modelled using two-dimensional depth averaged finite element method to estimate the impact on the hydrodynamic and sediment transport conditions. The examination showed that engineering measures at the downstream part of the reach were more effective than structures at the front, when taking both hydrodynamic and the more long-term impacts from sediment transport into account. Although the results of the sediment transportation are uncertain, the long- term consequences with investigated engineering measures can be concluded to have negative impact on the sustainability of the reach, however short-term improvements can be achieved. Other factors such as stability, material use, economics and marine conditions were not treated in this project but are vital for a reliable solution.

The report is about reducing the Eigen weight of a reach stacker in order to obtain decreased fuel consumption. The detail the product development treats is the telescopic boom. By using steel of higher strength the dimension can be decreased, which in turn results in a reduced weight. Suitable steel for the application might be the high strength structural steel of designation S690QL. With support of calculations and CAD simulations the possible weight reduction is assumed to amount to 28%.