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468 Uppsatser om Stair manufacturing - Sida 15 av 32

Optical and Structural Properties of CuxS Quantum Dots Concerning H2O/Ethanol Solvent Ratio

Nanotechnology, one of the most interesting sciences today will no doubt have an enourmous impact on tomorrow's society and industry. One of the most interesting nanomaterial that has been discovered is the semiconductor quantum dot (QD). This material shows interesting novel properties such as a size-dependent band gap, which is an effect caused by the quantum confinement effect in all three dimensions. Due to this phenomenon the absorption spectrum can be tuned to the desired value by adjusting the size of the QD.This thesis aims to investigate how the solvent ratio of H2O/Ethanol affects the optical and structural properties of copper sulfide QDs manufactured in a chemical synthesis way using modern microwave heating. The process of manufacturing QDs using chemical synthesis often involve a capping-agent to prevent the QDs from agglomerate into bigger structures.

Förbättrad resistansmätning för grova aluminiumledare

The goal with this master thesis has been to evaluate and to examine the stationary resistance bridge. The resistance bridge uses a 4-point measuring to determinate the resistance, which is used in the manufacturing of the conductor. It is then used when the resistance is to be decided for coarser aluminium conductors. A conductor has to fulfil certain demands to be able to move forward in the process. One of these demands is the resistance in ohm/km, which has demands that the measure values of the resistance bridge are as true and precise as possible.

Design och tillverkning av en stereoanläggning med aktivt delningsfilter

This thesis is the result of the author?s interest in music and electronics, namely the design and manufacturing of a stereo sound system with an active crossover. In short it can be stated that an active crossover has many advantages over its traditional passive counterpart. The active design naturally results in a more complex system comprised of a multiple number of components. This report deals with the theoretical aspects of preamplifiers, crossovers and power amplifiers as well as power supply and control.

Förbättrad resistansmätning för grova aluminiumledare

The goal with this master thesis has been to evaluate and to examine the stationary resistance bridge. The resistance bridge uses a 4-point measuring to determinate the resistance, which is used in the manufacturing of the conductor. It is then used when the resistance is to be decided for coarser aluminium conductors. A conductor has to fulfil certain demands to be able to move forward in the process. One of these demands is the resistance in ohm/km, which has demands that the measure values of the resistance bridge are as true and precise as possible. The stationary resistance bridge had been examined through various kinds of measurements to be able to see how stable the system is and how to obtain a measure value as optimized as possible.

Automatiserad konstruktion av analoga förstärkare

The last few decades the development in the field of electronics has been huge. The components performance gets better at the same time as the manufacturing cost decreases. Many of the design moments that have to be done, are done automatically today, but it can get better. Especially for analog circuit design.At Electronic System in Linköpings universitet, research is in progress to develop a tool that can design analog circuits in reasonable time. It means that it has to size the components (transistors, resistances, capacitances etc), so that the circuit can fulfill the performance requirements.

The effect of rapeseed oil and palm oil supplement and milking frequency on milk yield and milk fat quality

Milk fat is an important feature in many different milk products and other foodstuffs and it is often crucial for the dairy plants that the milk fat is stable for different manufacturing processes. Lipolysis is the enzymatic degradation of fat and is the one of the causes for an elevated amount of free fatty acids (FFA) in milk. Further, the change in fatty acid (FA) composition in milk can affect the stability of the product and also the manufacturing process. Both internal and external factors, at farm level or at the dairy plants can affect both FA composition and content of FFA. Milking frequency (MF=number of milkings per cow and day) and the composition of feed are two examples of factors generally performed at farm level. The objective of the present study was to evaluate how FA composition of milk and amount of FFA are influenced by two different ingredients supplemented to concentrate.

Uvärdering och förbättring av kvalitetssystem: en fallstudie vid Pfizer Global Manufacturing, Helsingborg

Examensarbetet berör utvärdering och förbättring av kvalitetssystem vid Pfizer i Helsingborg. Data har samlats in, analyserats och därefter har förbättringsförslag tagits fram. Huvuddelen av datainsamlingen består av intervjuer som sedan analyserats med hjälp av teori inom TQM och gällande ISO standard. Övriga delar av datainsamlingen består bland annat av benchmarking. Svagheter med systemet har identifierat och rör bland annat, avsaknad av helhetsbild, kontrollinriktat samt suboptimeringar.

Planering & produktionsstyrning : Lean filosofin vid produktion av asfalt

Lean is a production philosophy which is about increased resource use while meeting customer requirements. The foundation of lean comes from Toyota and their production philosophy The Toyota Way. Professor Jeffrey k. Liker has worked with Toyota's production philosophy and Lean for a long time and has created a 4 P model and 14 principles that characterize the Toyota production system (TPS), which many sources refer to.The aim of my work is to study the working procedure of asphalt projects from sales to the laid asphalt with a focus on planning and production management. The goal is to examine how the lean philosophy can be applied in planning and production to simplify the flow of asphalt projects based on Likers model and principles.

Design och optimering av lagertätning : Hos hydrodynamiska oljeglidlager med labyrinttätning

ABB Motors and Generators manufacture large AC machines with oil lubricated plainbearings. The machines have occasional problems with oil leakage from the bearings. aproblem that ABB wants to be solved.In this thesis the cause of this leakage were investigated, with focus on the bearingseals.The purpose of this work was also to suggest amndments for preventing thisproblem. , and to suggest improvements that can prevent this. The first step was todo a literature survey of earlier work on this problem, study the theory ofhydrodynamic bearings and different types of seals and their properties.

Bakhjulsupphängning, fyrhjuling

Highland Group AB was helping a customer of theirs to create an All-Terrain Vehicle (ATV), a project Highland has never been involved with before. For the wishbone arms of the wheel suspension, traditional manufacturing methods and tubes with cylindrical or square shaped cross section was preferred. We performed a simulation where the ATV was driving on a bumpy road too see the forces involved. With the results we proceeded to calculate the strength of the concepts to find out which is best suited for the tough environment in which the ATV is used. The concept that turned out to be the best was a wishbone made of circular cross section, which had good structural strength and did fulfill the demands that we required for the construction.

Hållbar design för en bättre värld -med hemlösa i fokus

The aim of this project is to examine the needs and problems that exists amongst homeless people and to develop a solution that will help them in their everyday life. Since the homeless are a relatively large vulnerable group i Sweden, their everyday lives could be made easier in many ways.A clear definition of the target group is put together to create a good starting point. What state and help orginazations do to help the homelss and the society?s view of the homeless is also relevant and has been documented. Four personal stories have been put together to desicribe cases of clear problems existing in everyday life.Several interesting problems has been defined from the research and acceptance in the communtiy, desire to be seen and heard and a lack of confidence were the main needs.

Honung och biodling : honungens ursprung, egenskaper och effekter på människans hälsa

This report describes honey, its origin, properties and effects on human health. Honey has been used for a long time in most civilizations and apiculture is an important activity sector in many parts of the world. The trend is an increase in honey production but a decrease in the number of beekeepers in Sweden. Honeybees live in a highly developed society with a strong hierarchy and a well organized distribution of the tasks. They visit a broad spectrum of plants and collect nectar to store it as honey.

Utveckling av 300 kg HD Lightlift för belysning och liknande laster

The company LightLift Esystems AB manufactures patented motorized lift systems for the illumination of halls with high ceilings. The company wants a new design for singular heavy lights in order to be more competitive.This project consists of the development of the new design under the requirements and specifications imposed by the company. The new design must support lights up to 300kg and keep the overall dimensions as low as possible without modifying the driving unit.This document contains all the designing steps followed to reach the final solution as well as the material selection, manufacturing process and assembly of all the parts that form it.The solution obtained shows to be very competitive with other alternative products, since this new design triples their maximum load capacity while the dimensions are very similar.In this context, the optical appearance was also very important to the company and so it was another main objective of this project. From an aesthetical point of view, the final solution proves to be very compact and versatile since it can either be hidden behind a false ceiling or covered by a plastic case that gives the design a very nice look.Finally, the solution achieved fulfils all the requirements and specification previously imposed. It is reliable, compact, cheap to manufacture, easy to assembly and it has a good optical appearance. .

Risk analysis and a study of risk awareness and risk communication at LEAF Gävle concerning dust explosions

The purpose of this report is to study the risk of dust explosions at the candy manufacturing plant Leaf Sverige in Gävle, Sweden. The risk analysis was conducted with a preliminary hazard analysis, PHA and event trees. The analysis focuses only on the risk posed to employees and material damages at the plant. No third person injuries have been considered. Another purpose of this report is to study risk awareness and risk communication concerning dust explosions.

Studie till uppstartande av annonskatalog

Sten Jonsson wants to start a production of an advertising catalogue for small companies in Sweden. Acatalogue where the advertisingcost is so low that most of the companies can afford to participate. Thecompanies who will advertise should be manufacturing companies in trades of carpentry, sheet metalworkshops, forging workshops and engineering workshops.The catalogue will facilitate for the manufacturer to reach the costumer without any middleman.Without a middleman creates a possibility for an opinion about the product at the same time as theprice can be held low. A catalogue of this type would benefit the marketing of the companies at the sametime as it would generate an occasion for innovations.The possible target groups are property companies, construct companies and farmers.A market research has been carried out contained a postal interview and a phone interview. Themarket research carried out to get an understanding in what the companies think about the idea butalso to see if the companies are in interest of advertise in the catalogue.

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