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1418 Uppsatser om Forest properties - Sida 53 av 95
Automatiskt avvägningssystem för obemannad undervattensfarkost
This master thesis work was done at Saab Underwater Systems AB, a company at the cutting edge of underwater technology. Here torpedoes and other underwater vehicles are developed and manufactured. The major customers are navies of different countries, mostly the Swedish navy. The aim of this master thesis is to develop, construct and evaluate an automatic Trim System for Unmanned Underwater Vehicles. The task of the system is to change the position of the centre of mass and the vehicle?s total mass or volume.
Ny konstruktionslösning och kostnadsförslag för stansverktyg
The task for this thesis is to design a tool that is used to cut-out preforms of thermoplastic adhesive and also to make an estimate of costs for the stamping tool. The tool is used in the repair process at the MCM production line.
The result of gathered information has affected how the design of the stamping tool has developed. The handling of thermoplastic adhesive in the repair process is one of the factors that influenced the design. The adhesive is sensitive for exposure to moisture. Therefore an automated feeding system of the adhesive is not recommended.
The users wished for an automated stamping tool.
Valsningsteknik för extremt höghållfasta tunna stål
New high strength steels require improved cold rolling techniques. The aim of this degree project was to develop a new and money saving cold rolling technique to manufacture steel strip for saw blades. The work is based on earlier rolling experiments made with a high carbon steel grade at LuCoil Steel AB. The work also focused on the mill requirements to cold roll high strength steels. The results show that LuCoil?s existing cold rolling mill was actually designed for rolling low carbon steel.
Hydroakustisk kommunikation med bandspridningsteknik
This thesis investigates techniques for stealth hydroacoustic communication using spread spectrum. The Swedish naval defense organisations have a vision that all their units should be able to communicate with each other, even between underwater vehicles. But the properties of water makes it a complex channel to use for wireless communications. Radiomagnetic waves have very limited range in water, therefore acoustic waves are used. In this report the basics of wireless communication systems are described including source coding, channel coding, modulation techniques as well as different techniques for spread spectrum.
En studie om vilkenundervisningsmetod som ger störst inlärningseffekt hos barn : En jämförelse av kunskapstest före respektive efter undervisning
The aim of this thesis is to study the teaching methods that provide the greatest learning effect for children in grades 6 in the subject of physics. One class was divided into three equal groups, each group was educated in a specific way. The three teaching methods that have been investigated are: film with reflection, laboratory work and traditional lecture- teaching. The research question of the study is: "Which method of three selected, causes the greatest understanding of the properties of air??.
Kaffesump som substrat i biogasanläggningar eller som bränsle i fjärrvärmeverk : en studie av effekter på växthusgasutsläpp och kostnader
Each year, the coffee machines at Ericsson in Kista produce around 100 tons of ground coffee waste.The companies Coor Service Management, Löfbergs Lila and Selecta are all responsible for differentstages in the logistical chain in delivering coffee and, together with Ericsson, they want to increasetheir environmental benefit. The plan is to produce biogas through anaerobic digestion instead ofincinerating the coffee waste in a heating plant. The results are to be presented as different businesscases in which different biogas plants are compared with the reference case (heating plant),comparing costs and environmental impacts.There are two major environmental benefits from producing biogas; reduced carbon dioxideemissions from when fossile fule is replaced by carbon neutral biogas, and reduced emissions fromreturning digestate from the bio reactor to farmland instead of using industrial fertelizer.In order to determine the biogas potential in coffee waste, a couple of properties had to bedetermined in a laboratory. Properties such as the dry substance content, heating value, moisturecontent and ash content. The results show that 100 tons coffee waste could produce around 16 500Nm3 biogas which would contain 163 MWh.The biogas reactor and upgrade plant both need energy gas to function and uses around 14 MWh ofthe produced gas.
Framkomlighetsanalys med hjälp av en digital terrängmodell och kartdata
Driveability analysis of terrain data offers an important technique for decision support for all kinds of movements in the terrain. The work described in this report uses a high resolution digital terrain model generated from the laser radar data and further processed by the Category Viewer program, and information from the Real Estate Map. Properties of features found in a filtering process are calculated and compared with a set of rules in a knowledge base to get a driveability cost. This cost is then visualized in a graphical user interface. An evaluation of what driveability is and what it is affected by is performed, and a general cost function is developed, which can be used even if not all relevant information is available.
En studie av zero knowledge-identifikationsprotokoll för smarta kort
Zero knowledge protocols is a lesser known type of protocol that can be used for identification. These protocols are especially designed not to reveal any information during an identification process that can be misused later on, neither by the one who should be convinced of the identity of the user, nor by anyone else that is eavesdropping. Many of these protocols are also especially designed for implementation in smart cards. The more common type of card with a magnetic stripe has during the last few years become more susceptible to attacks since they are easily copied. Smart cards combined with a secure identification protocol has been predicted to be the solution to this problem.
Utvärdering av Hultdins prototyp för portabel bro (drivningsbro) :
Stronger demand has been put on forestry to show environmental considerations during harvesting. This is especially for crossings of brooks with sensitive elements and great care should be observed when they are to be crossed during harvesting by logging machines. For that reason Hultdins has constructed a portable bridge that can be used for those occasions. The bridge has been developed in accordance with wishes from SCA forest, since they have a great deal of brooks in their forests and in private forests from where they buy part of their wood supply.
The aim for this report is to investigate if this portable bridge can be of interest for the forestry market. The research has been made at SCA skog in Medelpad and Norrskog in Medelpad.
Hur främjar förskollärare barns motorik i förskolan och hur viktig anser de att den är?
AbstractThis work is about children?s motor activity. You can often hear in media about sedentary children, and that one of the factors which contributed to this is computers and things like that. The main goal with this work is to find out how preschool teachers take care of children?s joy of movement and how they work to promote children?s progress of motor activity.
Finansiell analys med avseende på risk: En studie av svenska fastighetsbolag
The purpose of this thesis is to investigate the status of Swedish real estate companies in terms of financial health and risk of financial distress. The background is the ongoing financial crisis, which partly can be derived from the American real estate sector. Publicly available accounting information from 16 listed real estate companies has been analyzed for a period of one year using financial ratios covering both the operational and financial activities. We find that the deceleration in the economy and in the real estate sector have forced the real estate companies to make large write downs, in line with the relatively new accounting rules, IFRS. Write downs are likely to reoccur during the following periods and real estate companies will therefore probably be forced to continue to show negative results.
Analys av haptoglobin i bovint serum med surface plasmon resonance biosensorteknik :
The concentration of acute phase proteins in serum is altered as a response to inflammation, infection or trauma. this makes these proteins potential biomarkers of unspecific pathological processes. In cattle, haptoglobin and serum amyloid A are the two acute phase proteins that show the largest increase in serum concentration as a result of inflammatory processes. The haptoglobin concentration has been shown to correlate to clinical signs as well as inflammatory processes found at post mortem examination. This feature could be useful prognosis of the individual as well as for monitoring the health status of a herd or identifying carcasses that shold be examined closer at the slaughter-house.
Textilteknisk menisk
Denna rapport presenterar det examensarbete som gjorts i samarbete med företaget Artimplant. Syftet med arbetet är att ta fram en prototyp av ett meniskimplantat i trikåteknik. Det kräver stickning av en given form och att prototypen ska inneha vissa egenskaper.Ämnesområden som berörs under arbetets gång är textiltillverkning med inriktning mot väfttrikå samt medicinsk textil. Förutom textila ämnesområden tas även ämnen som knäledens anatomi och meniskens uppbyggnad, funktion och skador upp. Kunskaper inom dessa områden krävs för att på bästa sätt ta fram prototyper av meniskimplantat.Att sticka det triangulära tvärsnittet och den böjda formen som krävs för ett meniskimplantat har varit ett arbete som pågått under hela projektet.
Kvalitetssäkring av servicelämnare för skogsbrukets arbetsmaskiner : Intervjuer och förslag till utveckling
In this study we have examined the possible quality standards and methods for applications with service workshops in the forest industry. The purpose of the methods presented here was to start the work of standarardising the maintenance service in the industry and be of use for service providers in their quality effort.The methods we used to accomplish the study were interviews and field visits together with a comprehensive literature research. Our results are presented in the form of four solution proposals: a standard based on existing SIS standards for terminology and key indicators, checklists that are filled in by mechanics with customer participation, the construction of a instructions database, and the implementation of the method 5s.We believe our suggestions can help the service providers in the four problem areas that we have identified: long term strategy, documentation, recruitment of competent technicians, and standard procedures in their operations. These improvements will be beneficial for both the service provider and the customer..
Utveckling av logistikflöde : En undersökning av införande av extern kittning av hydraulslang vid Komatsu Forest AB
Komatsu Forest AB tillverkar skogsmaskiner och aggregat. I monteringsprocessen är hydraulslangar en av komponenterna som hanteras och lagras per artikelnummer. Idag genomförs intern kittning då slangar plockas ur respektive lagerlösning mot en specifik monteringsoperation. Kittning innebär att delar och komponenter sorteras i set, så kallade kit, innan de levereras till monteringsoperationer. Genom extern kittning som utförs av leverantören kan eventuellt flödet av hydraulslang och utnyttjandet av ytan i anläggningen bli mer effektivt då kitten är färdiga när de anländer till anläggningen. Syftet med arbetet är att identifiera det mest produktiva och kostnadseffektiva arbetssättet gällande hantering av hydraulslangar från beställning till montage på maskin.