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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

Konstruktion av en surdegsvagn till bageriproduktion

Zelic, Dani, Hjelm, Markus January 2017 (has links)
This thesis involves the process of designing a wagon for the company Majgården AB, a company working with bakery production. The used method follows mostly Fredy Olsson´s (1995) work process using Principle Design as well as Primary Design in order to design a final concept. Initially, in the beginning of the thesis, it was analyzed how the product will be used and in what kind of environment. The analysis allowed a definition of requirements that the product needs to fulfill. Next step included extracting different product sketches that could be used as possible solutions. The solutions were compared against the requirements and a final, optimal concept was chosen to continue the work with. The final sketch was then further improved. The design of the final concept was then fully finalized with help of a 3D program.
182

Development of an FPGA based Trigger for Slow Moving Events for the EUSO-TA Telescope

Guldevall, Peter January 2017 (has links)
No description available.
183

Karlläggning och analys av lagerlayout : Effektivisering av plock- och utleveransprocess / The Mapping and analyzing of a warehouse layout

Helander, Jakob January 2017 (has links)
No description available.
184

To evaluate source sorting programs in household waste collection systems

Dahlén, Lisa January 2005 (has links)
When evaluating and comparing household waste collection systems, various aspects are relevant to consider, e.g. environmental objectives, technical function, operating cost, types of recycling materials collected separately, property-close collection or drop-off system, economic incentives, information strategies, residential structure, social codes, etc. Data describing the actual waste flow is the basic input to evaluating the function of source-sorting programs. The questions raised are: How can household waste quantities and composition be measured? How can waste flow data from different collection systems be interpreted and compared? What factors influence the output of source-sorting programs? The usefulness and weaknesses of solid waste composition studies are discussed. Multivariate data analysis is applied in order to obtain an overview of collection and composition data, and identify influential variables, clusters and trends. In a case study, curbside collection of recyclables and weight-based billing respectively led to increased source-sorting activities. Other influential factors are listed and discussed. Eight indicators are proposed for facilitating comparisons of collection systems in an easily comprehensible way. / <p>Godkänd; 2005; 20061214 (haneit)</p>
185

Mine Production Assurance Program- Development and Application

Lanke, Amol January 2016 (has links)
ssuring production forms a crucial part of mining business profitability. Factors related to various mine operations, activities and business processes can threaten required/planned mine production.   To address problems and ensure production level in mining, it is necessary to implement a mine production assurance program (MPA). In order to propose a guideline and its component, this study started by reviewing four such techniques used in process industries. Comparing the tools, techniques   and focus with mining productivity and production factors, it was observed that applicability of these methods for mining is limited due to lack of focus on equipment focus, cost focus and other parameters. Similarity of objectives and requirements of equipment focus lead to conclusion that PAP from oil and gas industry seems to be method which can guide MPA.\parAs a basis of MPA, an index is required to create a clear relationship between different situations which can occur in mining operation and production loss. A literature review on mining productivity improvement methods shows availability, utilisation and production performance of equipment are the key factors in determining overall production. A single index applicable for chain operation in mining is needed. A Mine Production index (MPi) is thus proposed. This index involves all three parameters for equipment productivity mentioned above.  Weights associated with MPi calculation for bottleneck equipment can point out critical factors in equipment operation. Once bottleneck equipment and relevant critical factors are known, further analysis can be carried out to determine the possible causes of production loss. By using MPi for machine operations, it is possible to rank machines in terms of production effectiveness. When the study applied MPi to chain operations in a mining case study, a crusher was determined as bottleneck equipment.\parMining operation is heavily influenced by internal and external uncertainties. Operational uncertainties related to equipment includes its key factors leading to production i.e. availability, utilisation and performance. These factors are in turn dependent upon downtime, idle time, rated capacities. External parameters related to weather are based upon location of mining operation. Influence of these factors on production volume, could be used for better decision making during mining operations optimization. To effectively propose a method for correlating internal and external parameters with production volume, case studies in an open pit mine were conducted. During these case studies a multi-regression modelling methodology is used. It was found that at system level availability is important criteria for increasing production. At level of shovel and truck fleet, availability and utilisation are most important characteristics to be focused for reduction in production uncertainty. Environmental factors are although correlate to less variation in production volume compared to operational factors.  Amongst considered environmental factors snowfall is highly influencing followed by rainfall.  At system level  use of maximum capacities of equipment and availability are key point for increasing production. Based on analysis of internal operational factors, it was concluded that capacity of shovel and trucks is underutilised. For shovels availability and idle time are influential factors. For trucks utilisation is highly correlated to production volume generated.  Analysis of environmental factors concluded that, period of zero snowfall and rainfall are perfect condition for equipment production increase. Period when either snowfall or rainfall stabilisation are also equivalent to achieve higher production. Although these production levels are significantly less than period without snow and rain
186

Difference in Jump Height and Jump Length in Youth Soccer Players Selected or Not Selected for the National Team

Arvidsson, Julia January 2017 (has links)
Background: With the aim of professional status and sporting success, selection processes and talent identification in youth players are common in football clubs and national teams. Football requiring different types of abilities, standing out in certain abilities can be important in the selection process for national teams. Physical abilities including maximal power can differ between players in the same age group due to growth and maturation and might therefore be important factors in the selection process. Previous studies have mentioned maximal power as one of many performance indicators for football performance. However, few studies have investigated its importance regarding youth players selected or not selected for the national team. Aim: The study was designed to measure and compare jump height and jump length in three different jump tests between youth soccer players selected or not selected for the national team. Methods: Twenty-two (n=22) players, eleven national players and eleven non-national players performed three different jump tests. The players were 17±2 years old from the club Halmstads BK, Halmstad. The study was an observational crosssectional study that was designed to measure and compare jump height and jump length in three different jump tests between youth soccer players selected or not selected for the national team. The jump tests that were used in the present study was Countermovement Jump (CMJ), Abalakov Jump (AJ) and Standing Long Jump (SLJ). Mean scores for the tests in both groups were analyzed and compared and the criterion level for significance was set to p ≤ 0.05. Results: The results showed a significant difference between the groups regarding jump height in CMJ (p=0.013) and in AJ (p=0.010). No significant difference was found regarding jump length in SLJ (p=0.084). Conclusion: The findings of this study showed a significant difference in Countermovement Jump (CMJ) and Abalakov Jump (AJ) between national players (NP) and non-national players (NNP). The study found no significant difference between the groups in Standing Long Jump (SLJ). The results indicate the use of maximal power as a performance indicator and part of the selection of players to national teams. Anthropometric data (age, weight and height) was similar between the groups, therefore, other maturation and growth factors together with biological age are aspects that might have influenced the results. Future studies are suggested to investigate maturation status and its importance for maximal power in national players and non-national players.
187

Technical and economic evaluations of the battery energy storage systems for a residential building along with the photovoltaic system

Amjadi, Hamid Reza January 2017 (has links)
Photovoltaic (PV) system and the battery energy storage system are promising to supply power for residential buildings. Solar panels along with the battery energy storage (BESS) presents an opportunity for the households to use a much greater proportion of the solar photovoltaic (PV) to generate the electricity and minimize the need of purchasing expensive electricity from the electricity grid. This project presents a framework for conducting the economic and technical analysis of residential house along with the integration of solar panel units and the BESSs. In this study, the electricity consumption of a multi flats building (Magnolia) in Helsingborg and the PV production profile under local weather conditions are compared and analyzed. The proposed framework is developed by considering different prices of electricity of the existing electricity market in Sweden as well as the investment costs for the solar PV units and BESSs. The economic analysis is carried out based on different economic measures such as electricity price, simple payback analysis, net present value, payback analysis based on funding and without funding, and reduction in carbon-di-oxide (CO2) emissions. Technical evaluations of the BESS are carried out based on peak shaving purpose and overproduction from the solar panels. and The results show that ten 28 kWh of the BESSs in Magnolia building is required in order to meet the customer electricity demand and reduce the stress on the electricity grid as well as power cost and size of the fuse. Furthermore, the customer saves 154256 kr yearly, with the payback period of 14 to 20 years, which is almost similar to the expected lifetime of such a BESS.
188

The actinorhizal symbiosis of the earliest divergent Frankia cluster

Nguyen, Thi Thanh Van January 2017 (has links)
In recent years, the need to reduce reliance on synthetic nitrogen fertilizer has led to extensive research on biological nitrogen fixation, especially on root nodule symbioses. My study focuses on actinorhizal symbioses, the symbiotic interactions between members of nitrogen-fixing soil actinobacteria from the genus Frankia and a diverse group of plants from eight families, collectively called actinorhizal plants. Frankia cluster II has been shown to be sister to all other clusters. Thus, one of my aims was to gain insight into this cluster to get more information about the evolution of actinorhizal symbioses. The first sequenced genome of a member from this cluster Candidatus Frankia datiscae Dg1 originated from Pakistan. This strain contains the canonical nod genes nodABC responsible for the synthesis of lipochitooligosaccharide Nod factors. In this thesis, we obtained three Frankia inocula from North America (USA), one from Europe (France), one from Asia (Japan) and one from Oceania (Papua New Guinea). Thirteen metagenomes were sequenced based on gDNA isolated from root nodules of Datisca glomerata (Datiscaceae), Ceanothus thyrsiflorus (Rhamnaceae), Coriaria myrtifolia and Coriaria arborea (Coriariaceae). This study shows that members of Frankia cluster II come in teams, helping to explain the ability of cluster II to nodulate a wide host range, four families from two orders. The inoculum from Papua New Guinea, the only sequenced strain from the Southern Hemisphere so far, contains a new Frankia species, which was proposed as Candidatus Frankia meridionalis. All cluster II strains in this study contain the canonical nod genes nodABC, with the exception of the strain from Papua New Guinea which contains only nodB’C. All North American metagenomes also contain the sulfotransferase gene nodH. This gene shows host plant-specific expression in that it was expressed in nodules of C. thyrsiflorus but not in D. glomerata. Phylogenetic analysis and transposase frequencies of the new genomes strongly support the hypothesis that the extension of the cluster II host range from Coriaria to Datisca occurred in Eurasia and that cluster II strains came to North America via the Bering Strait. To acquire more information of the influence of the host plant on the behavior of the microsymbionts, the bacterial metabolism in nodules of D. glomerata (Cucurbitales) and C. thyrsiflorus (Rosales) were compared at the level of transcription. The system to protect nitrogenase from oxygen in Ceanothus nodules seems to be more efficient than in Datisca nodules, whereas the bacterial nitrogen metabolism is likely to be similar in both host plants. The amino acid profile of D. glomerata nodules shows that the nitrogenous solutes are dominated by glutamate and arginine, supporting the suggestion that Frankia in D. glomerata nodules exports an assimilated form of nitrogen, most likely arginine. Thus, our data show that cluster II Frankia strains differ from all other Frankia clusters with regard to the presence of the canonical nod genes and their nitrogen metabolism in symbiosis. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Manuscript. Paper 3: Manuscript.</p>
189

Shapes of Spacetimes : Collected tales of black holes

Jakobsson, Emma January 2017 (has links)
In theory, the existence of black holes is predicted by general relativity. In reality, there is a general consensus that they exist in space; in particular at the center of many galaxies. The theory of black holes has been around for decades, but there are still interesting questions calling for attention. This doctoral thesis and its four contributions touches upon some of these questions. One challenging theoretical aspect of black holes lies in their definition, the event horizon. For several reasons, this definition is not satisfactory in many contexts, and alternative horizons based on the concept of trapped surfaces have been suggested to take its place. The question raised in Paper I has to do with the location of such surfaces in a simple model of gravitational collapse, the Oppenheimer-Snyder model. A different scenario of gravitational collapse, that of a null shell of dust collapsing in flat spacetime, is the starting point of the original formulation of the Penrose inequality. By a reformulation, this inequality can be turned into a purely geometric relation in Minkowski space. In Paper IV we formulate and prove a (2+1)-dimensional version in anti-de Sitter space. The Penrose inequality sometimes goes under the name of the "isoperimetric inequality for black holes". In Paper III a different kind of isoperimetric inequality is discussed (with less rigour), namely that of the volume contained in a black hole with a given area. In Paper II, the subject of limits of spacetimes is visualized. Again, (2+1)-dimensional anti-de Sitter space finds its use, as a one parameter family of surfaces, capturing the geometry of charged black hole spacetimes, is embedded in it. Thus different limiting procedures are illustrated. Finally, interesting models can be constructed by cutting and gluing in spacetimes, but in doing so one needs to take care, in order to obtain a physically realistic model. With this background as motivation, a study of Lorentzian cones is given. Taken together, all of these contributions make up a collection of interesting aspects of black hole geometry, or, shapes of spacetimes.
190

Structural Investigations of HiPIMS-deposited Diamond-Like Carbon Thin Films using Raman Spectroscopy

Eriksen Tell, Andreas January 2017 (has links)
Diamond-like carbon (DLC) is a versatile material which exhibits excellentmechanical, electrical and optical properties making it suitable for applications rangingfrom biomedical implants to engine components. The properties of DLC thin films aredetermined by the bonding configuration (sp3/sp2 fraction) of its carbon atoms. Inorder to prepare DLC thin films for desired applications, it is essential to control andestimate the sp3/sp2 fraction precisely. Raman spectroscopy is widely employed for the estimation of sp3/sp2 fraction due toits non-destructive nature, high probing depth and possibility of quick acquisition. Thequality of information obtained from Raman analysis depends largely on the structureof DLC thin films, which varies from one deposition method to another. Using theexisting approaches for the estimation of sp3/sp2 fraction for a particular type of DLCthin films could entail large errors and thereby result in misleading conclusions. For anaccurate analysis of the film structure, it is therefore important that a carefullydesigned strategy is employed. In this work, Raman spectroscopy is employed forstructural investigation of DLC thin films deposited by High Power ImpulseMagnetron Sputtering (HiPIMS). Owing to the unique DLC film properties obtainedfrom HiPIMS, Raman spectroscopic investigations were made by developing ananalysis routine relevant for HiPIMS-deposited films. The developed approach isvalidated by complementary analysis of film density. The method is further employedfor investigating the compressive stress and thermal stability of the resulting films. Theanalyzed films were deposited using different buffer gas (Ar and Ne) and ion energy toproduce a range of sp2/sp3 ratios. Raman measurements were performed using visible(532 nm) and UV (325 nm) lasers. Film density was determined using X-RayReflectivity (XRR) and chemical composition using Elastic Recoil Detection Analysis(ERDA). The compressive stresses of the films were determined usingwafer-curvature method and thermal stability of the films was investigated byperforming Raman measurements on films annealed from 100 degrees C to 600degrees C. By developing an analysis routine and employing appropriate fitting method, it wasshown that the Full Width at Half Maximum (FWHM) of the G peak in the Ramanspectrum is the most relevant parameter for estimating the sp3/sp2 fraction. Theaccuracy of the analysis routine was verified by studying the evolution of sp3/sp2fraction and film density with respect to ion energy. The correlation between sp3/sp2fraction and film density was good. The differences in mass density and compressivestresses between Ar- and Ne-HiPIMS deposited films were also found to beconsistent with the estimated sp3/sp2 fractions. The structural evolution of theannealed films, investigated by Raman spectroscopy, showed that the Ne-HiPIMS filmsexhibit a transition from sp3 rich structure to sp2 rich structure at ~450 degrees Cwhereas the transition for the Ar-HiPIMS films occurs at ~300 degrees C. This impliesthat the Ne-HiPIMS films are thermally more stable than the Ar-HiPIMS films.

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