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345 Uppsatser om Laser Cutting - Sida 16 av 23

Does tree removal along railroads in Sweden influence the risk of train accidents with moose and roe deer?

After the storm Gudrun in 2005, the Swedish Transport Administration started clear-cutting of railroad corridors to reduce the risk of trees falling down on the tracks. Simultaneously, train accidents with moose and roe deer have become more frequent and the costs for consequent delays and repairs of engines are of growing concern. There is reason to assume that tree-clearance of railroad corridors may have contributed to an increase in number of accidents with moose and roe deer because the cleared areas provide attractive forage and thus may attract wildlife. The objective of my study was to investigate how clearing of trees affected the number of accidents with moose and roe deer. I compared deer-train collision frequencies before and after clearance of the selected railroads and compared these with uncleared control railroads in a BACI (before-after control-impact) approach.

Fyra västsvenska mediers syn på pressmeddelanden

Today most people are in agreement that the media industry is in crisis. Many newsrooms cut down on staff. At the same time the PR industry is growing. We wanted to research if this could affect the unbiased and independent news in our news media today. Today's newsrooms receive a lot of press releases every day.

Nytt spritsrör på TwinRoll typ TRPE : Undersökning av kostnad på spritsrör

This thesis describes possibilities for Metso Paper to lower their costs of spray pipes for their pulp wash press TRPE, with maintained good functionality and quality.Information that can be used by competitors has been censored in this version of the essay.To find solutions, alternative suppliers have been contacted and asked to quote. There has also been a new spray pipe designed. The manufacturing costs of the new design have been calculated.The thesis also contains a concept generation of an alternative product to the spray pipes in installations where a high pressure washer is used.To be able to ask other manufacturers of spray pipes to quote, a demand specification based on the currently used spray pipe was made. This was then sent to two alternative suppliers.An investigation of earlier used spray pipes, and the currently used, shows that the nozzles are a big part of the total costs of the spray pipes. To attempt to reduce the nozzles high cost an concept generation was made to find the best solution for a new design.There was a request that it should be possible to change the internal brushes in the spray pipe without cutting and welding.

Effekter av sjukgymnastiska behandlingsmetoder vid subacromial impingement: en litteraturstudie

Bakgrund: Subacromialt impingement syndrom (SAIS) är den vanligaste orsaken till skuldersmärta. Syndromet karaktäriseras av att smärta kan reproduceras genom rörelser som minskar utrymmet mellan acromion och humerus. Syfte: Syftet med studien var att kartlägga för vilka sjukgymnastiska behandlingsmetoder vid SAIS som evidensen är prövad, samt att undersöka vilken evidens som fanns för behandlingsmetodernas effekt. Metod: En litteraturöversikt genomfördes med artikelsökning i databaserna Pubmed, Cinahl, Amed och PEDro. PEDro-scale och SBU:s evidensgradering användes för att bedöma artiklarna.

Avståndskamera för utomhusbruk: en analys av optisk
triangulering med divergent ljuskälla

Denna rapport analyserar flera aspekter kring avståndsmätning med optisk triangulering, speciellt då ljuskällan ger en relativt bred ljusstråle. Vid optisk triangulering mäts avståndet genom att belysa scenen med ljusstrålar som bildar ljusfläckar där de träffar. Genom att betrakta scenen med en CCD-kamera förskjuten ifrån ljuskällan går det att beräkna avståndet till dessa ljusfläckar. Huvudsyftet är att undersöka möjligheterna att bygga en billig och robust avståndsmätare som skall kunna användas utomhus på en mobil robotplatform. Grundläggande principer såväl som teoretiska modeller beskrivs och analyseras.

Vad påverkar skogsägarnas naturhänsyn vid föryngringsavverkning i region Mellannorrland? :

The objective of this thesis was to investigate what influence nature conservation measures taken at regeneration felling. Factors analysed were the forest owners´ situation and their characters, and information activities from wood-suppliers and the Regional Forest Board (RFB). The inventory was performed with a posted questionnaire followed up by telephone to forest owners and a posted questionnaire to wood-buyers. The forest owners were grouped in three strata, depending on the quality results (D- polytax inventory) of the taken forest conservation measures, and for this investigation forest owners were sampled from the population in the tree groups. In total 73 % (41/56) of the sampled forest owners answered the questionnaire Group A (17 answers): Good judgement Group B (19 answers): Bad judgement Group C (5 answers): This group was formed from the forest owners that were informed, by RFB, about nature conservation measures and culture history consideration before the regeneration cutting.

Översvämningsrisker längs Funboån

Flooding events are no longer rare, floods occur all over the world. Accordingly, it is vital for the society and different authorities to work with flood mapping. To meet the goal of Uppsala kommun to map the risks of floods in Uppsala län, a map of the different areas around Funboån which are inside the area of risk for flooding have been developed.In the work, cross sections and the water flow have been measured. Moreover, an echo-sounding have been carried out in Funboån to map the bottom topography. From the bottom map and laser scanned data covering the study area, a terrain model was created.

Ackumulation av CO2 och CH4 i istäckta boreala sjöar : Hur förändras ackumulationen i sjöar påverkade av avverkning jämfört med referenssjöar?

The aim of this report was to quantify the accumulation of carbon dioxide (CO2) and methane (CH4) in ice-covered lakes in winter (October-March) during three consecutive years, and to assess whether the concentrations of DIC and CH4, as well as the ratio DIC:CH4 differs between years and between lakes affected by clearcutting and untreated reference lakes. Water- and gas samples were collected from four boreal lakes (two affected by clearcutting and two untreated reference lakes) located in Västerbottens inland in spring. The lakes were found to accumulate on average 91, 55, and 84 mgCm-2d-1 during winters 2012-2013, 2013-2014, and 2014-2015, mostly originating from CO2. The concentrations of DIC (autumn and spring) were higher in the affected clear-cut lakes compared to reference lakes for all years, including the reference year (2012-2013) before clear-cutting. No such difference was found for CH4 or the ratio DIC:CH4.

Markbaserade sensorer för insamling av skogliga data : en förstudie

En förutsättning för skoglig planering på alla nivåer är att man har en god uppfattning om tillståndet i den stående skogen. K valiten på de beslut som fattas kommer därför att vara direkt beroende av mängden och kvaliten på den information som samlats in. Sensorer som radar, lidar och olika typer av digitala kameror används idag med framgång för fjärranalys där skogen avbildas från ovan. Föreliggande arbete syftar till att belysa de tekniska förutsättningarna för att utnyttja modem sensorteknik även för markbaserade mätningar. Detta skulle i så fall öppna möjligheter att automatisera fångsten av skogliga data som därmed skulle bli kostnadseffektivare samtidigt som nya typer av data skulle bli tillgängliga.

ACL-rupturer hos fotbollstjejer ? riskfaktorer och prevention

Non-contact anterior cruciate ligament (ACL) injuries is a serius and traumatic injury to the knee that is common in female soccer players and often force the player to quit or lower the level of activity because of lost stability in the knee or from fear to suffer  a new injury. Female soccerplayers have a higher risk than their male counterparts to get an ACL rupture and especially adolescent females have a high risk. The most common causes to a non-contact ACL rupture is side-cutting manuvers and landing after jumping. Every other player with an ACL rupture develops osteoarthritis within 10-15 years from the time of injuryResults: The higher risk for females to incur a ACL rupture is due to smaller intercondylar notch, they?re in the follicular or ovulatory phase of their menstrual cycle, increased knee laxity, dominance in the quadriceps muscles, flexion in hip and valgus movement in the knee.

Samband mellan tjockleken hos PVD-skikt och förslitningsbeteendet vid svarvning

This project has as main goal to study the influence of the coating thickness, deposited by arc-PVD- technology, on the wear resistance of coated cemented carbide inserts in three different turning operations. An additional effort has also been made to develop a new test method for evaluating flank wear resistance. Three different coating types (Coating A, Coating B and Coating C) have been studied in three distinctive thicknesses (2, 4 and 6 µm) for each type. For two of the coating types (Coating A and B) special studies has been done with the thickest coating, creating two additional coating versions of the thickest coating, by changing various deposition parameters, with the aim to enhance the cohesive properties of the coating and lower the residual stresses at the cutting edge. The results show increased crater wear resistance with increased coating thickness for all coating types, but the amount of increase changes with coating type (Coating A>B>C).

En studie om förutsättningar för ledarskap i kunskapsintensiva verksamheter

Title: A study about conditions for leadership in knowledge-intensive firms.Authors: Cecilia Ekström and Niklas SandbergKeywords: Leadership, knowledge-intensive firm, hierarchies, followers.Background: Leadership is becoming one of our greatest social myths and is considered a total solution for many problems that occur in an organization. The view of leadership is usually from a top-down perspective, which contributes to an often underestimated view of the follower. Just as it is important to understand the leader's view of leadership, it is important to understand how employees view the structure from which the leader derives its legitimacy. The existing conditions in knowledge-intensive firms, such as autonomy, place special demands on the formal leadership.Purpose: The purpose of this study takes an employee perspective, to understand what the conditions are for formal leadership in knowledge-intensive firms.Method: A qualitative research method was used and empirical material was collected through interviews with employees in knowledge-intensive firms. The empirical material was analyzed by the respondents? mental images which were set against the theoretical framework of the thesis.Conclusions: The conditions for formal leadership in knowledge-intensive firms make it advantageous to have a leader with a withdrawn role.

Säsongsvis avverkning : det operativa traktvalets påverkan på den säsongsmässiga uthålligheten i ett bolagsdistrikts traktbank

Due to soft grounds in combination with seasonal variation in soil humidity, there is a lack of stands that are possible to cut during spring and autumn in some geographical regions. For Holmen Skog this sometimes means that a large proportion of the contracted private forest is cut during the winter when the ground is frozen. One consequence of this is that the proportion of winter stands in the stand bank of own forest increases while spring and autumn stands becomes a scarcity. This in combination with milder winters, especially when there is a long period of reduced bearing capacity in spring or autumn, means that the situation rapidly can become critical. The overall goal with this study was to generate basic data for decision support in the work to achieve a sustainable distribution between own forest and contracted private forest in the stand bank. The study took place at Holmen Skog, district of Umeå, during autumn 2007 and was based on interviews and an analysis of harvest planning and delivery data. The study showed that there is a problem with how the cutting is distributed between own and contracted private forest during the year and that it foremost is the proportion of winter thinning of own forest that has increased in the stand bank.

Faktorer som påverkar sjuksköterskans användande av omvårdnadsplaner : en litteraturstudie

The purpose is to illustrate the phenomenon of self-harm from a social psychological and sociological perspective. The purpose is furthermore to examine the role social relationships play in the individuals´ self- imagine and what role does identification play for anyone who harm themselves? We want to examine in what way social relationships are important and how they function for individuals who harm themselves, both once they have started to harm themselves, and if the relationships in any part caused the cutting to begin with.Questions:How do individuals shape their identity based on self- harm? Which self-image do individuals have who self-harm? Is there anything in the person's previous social relationships that have caused them to begin to hurt themselves?Method:In this paper we have analyzed five autobiographies. We have used open coding from grounded theory as analytical method and subject positions based on discourse analysis.Theory:We have used the Cooley concepts looking glass self, Foucault's theory of power, Giddens' concept of ontological security and existential anxiety.Results and Analysis:We found six different categories that we thought were central. These were negative self-image, guilt, lack of family support, negative experiences of others' views, the protective identity as self- harmer and insecure social relationships in school.Conclusion:The self-harming is a very complex behavior.

Jätteträd ? inventering, bevaring, skötsel samt rekrytering :

During the summer of 2007 I was employed by Högestad Christinehofs Förvaltning AB. My main task was to make an inventory of giant trees at the estate. Högestad and Christinehof,which with their total possession of 13 000 ha of land is the biggest estate in Scania. A giant tree is a tree with a diameter in breast height more then 1 meter. Trees of these dimensions are registered by Swedish authorities. Landowners with a giant tree on their property can receive a subsidy for cutting trees that are in competition with the giant tree.(Levenskog, 2007) Giant trees are important for biodiversity in the landscape and there are important habitats for different insects, birds, bats, lichens and funguses.

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