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314 Uppsatser om Voltage disturbances - Sida 19 av 21
Ersättningsmodeller för ballasttransporter : vid anläggning och underhåll av skogsbilvägar
Construction and maintenance of forest truck roads are a necessary element of industrial forestry. Payment for contracting services in this context can be done according to a number of payment models. This study will focus on the methods and consequences associated with a change of Holmen Skog?s payment model from per hour to per metric ton for ballast hauling.
The aim of this study is to improve the economic efficiency of Holmen Skog?s ballast hauling in construction and maintenance of forest truck roads. This is done by formulating and evaluating a proposal for a payment model based on crowns per ton.
Selenium in Swedish sheep production
Selenium (Se) is an essential trace element that is involved in several physiological functions in mammals. Mostly, Se is bound to proteins, many of them with enzymatic functions. A group of seleno-depending enzymes, glutathione peroxidases (GSH-Px?s), are important as antioxidants and protects against free radicals. The activity of GSH-Px is strongly regulated by Se storage in the liver.
Förfädernas berg? : en tolkning av fornborgen på Halleberg
The essay deals with the hill-fort on the mountain Halleberg, Sweden, its wall design, functionality, dating and its possible function as a central location and a place of worship of the ancestors.The Halleberg hill-fort consists of a 1500 meters long at times cohesive stonewalls which together blocked the mountain from its surroundings. Hallberg's natural vertical scree and cliffs along with the masonry blocked the whole mountain from the surroundings.The hill-forts, with few exceptions are largely not investigated archaeologically and its functionality and role in the ancient society is based on outdated research on the subject. The current archaeological interpretation is that hill-forts served as temporary defense in times of unrest or served as center of power for a social elite. The prevailing view in the archaeological sphere is that the hill-forts had a variety of functions and that its functionality and role in ancient society has varied.Halleberg´s strongest wall sections are at the mountain's south-eastern part where the natural driveway, Storgårdsklev is located. Along with the massive masonry of the walls in Bokedalen Storgårdsklev functioned as the hill-forts main entrance.
Besökares påverkan på Nordens Arks vargflock :
Zoo animals can be more or less disturbed by the presence of care takers as well as visitors. This may lead to stress and/or abnormal behaviour. The purpose with this study was to give a time budget of the behaviour of the captive wolves? (Canis lupus) and occurrence of behavioural disturbances and how this is affected of human visitors. For this purpose the wolves at Nordens Ark have been studied during off season as well as on season.
The zoo Nordens Ark is an idealistic foundation which was founded in 1988 and is located at Åby säteri, 130 km north of Gothenburg.
Konstruktion och byggnation av testfixtur för 10Gbit/s transpondermoduler
This thesis for the Master of Science degree was performed at Solectron Corporation in Norrköping. The background for the thesis was a need to develop and build two test fixtures to automatize testing and adjusting of transmitter modules (TX-fixture) and receiver modules (RX-fixture) which are head devices in DWDM-systems. The basic elements for the test fixtures are: Test board, switch board and DC/DC board. The main function of the test board is to handle communication between the transmitter and receiver modules and supply voltage to these modules. The test board was insufficient and modified with a microprocessor to handle the communication between the PC and the receiver module.
Korttidssjukfrånvaron Vård och Omsorg Öster : vad kan den bero på och hur skulle den kunna minskas
The health care sector Öster has the highest average absence due to short-time sickness in Örebro. It is the short-term absence that has the highest costs for the organisation, not just in money, but also in quality disturbances and administrative work. Health care sector Öster is divided into four areas with a manager for each. We have chosen to conduct our research within the special housings in area one and four, since these two had the lowest and highest short-term absences.The purpose with the research is to examine short-term absences among the health care personnel in the health care sector Öster, see what the absences depend on, and what can be done to solve the issue. We will compare the absences in the area with the highest respectively lowest short-term absences in order to see if there are any prominent differences between the two.
Analys och organisering av ö-drift för en samförbränningsstation vid Åmotsfors bruk
Åmotfors Bruk AB (ÅBAB) has today an inefficient production of steam for the
manufacturing of paper. Unpredictable energy prices and modernisation of the current
equipment has been the underlying factors to invest in a thermal power plant, mainly
driven by garbage. This facility will not only use the steam for paper production, it will
also generate electricity through a steam turbine. Today, when a fault on the supplying
line occurs which leads to disconnection of the external grid, all the support of electricity
to Åmotfors Bruk (ÅB) will disappear. This will lead to major interruptions in the paper
production, which will cause severe economical losses.
UTVECKLING AV PROCESSORPLATTFORM
Abstract The purpose of this project is to develop a modular processor card which is intended to work as a platform for Kitron Development Karlskoga. The modular processor card is meant to be used as a control system in development projects, mainly in medical and industrial products. The processor card will consist of a central unit with the basic functions for a control system. Furthermore there will be complete modules with machine commodity and programming, to pick exactly the necessary functions for a specific application. With consideration to the specification of the development and the main unit, I chose an adequate microprocessor (AT90CAN32) as core and interface circuits to stated border areas. The construction is first completed in the program MultiSim and then remade in the program OrCAD Capture. The programming language C was used in the software model.
Energisäkerheten för fjärrvärmeanläggningars bränsletillförsel i Mälardalsområdet
There are several energy systems in the Swedish society and to ensure the comfort and health of the citizens it is of importance that the different energy systems are functioning properly. District heating is one of these energy systems and many household depend only on district heating to warm up their homes.
District heating is dependent on several processes where every step needs to function in order to deliver the produced heat to the end consumer. Previous studies have investigated the distribution of district heating and how to make customers choose district heating as their heating method. The supply of fuel to the district heating plant has not been studied as much, even though it is an important part of the whole system. This thesis is a part of the project NORD-STAR (Nordic Strategic Adaption
Research), which has focused on climate adaption in the Nordic countries.
Syntes och egenskapskarakterisering av volframoxid framställd med magnetronsputtring
The system tungsten-oxygen has potential of being suitable for decorative coatings since ceramic coatings are often hard and wear resistant, and since modulations in oxygen content or incorporation of small ions could give bright colours. The aim of this report was to investigate the relationship between process parameters and the properties of the films, with the wear resistance being of special interest.Samples with tungsten to oxygen ratios in the range of 100:0 to 25:75 at% were made using reactive sputter deposition, either with constant gas flow, or gas flow controlled by optical emission of the plasma. The hysteresis of the system, which means that a certain gas flow will cause different pressure and/or target voltage depending on in what way the flow is reached, makes it interesting to control the process where the system makes the steep change from metallic tungsten to ceramic tungsten oxide. This is difficult and thus requires precise control equipment.The samples were analysed using X-ray diffraction, X-ray photoelectron spectroscopy and an empirical wear test suitable for small components like cell phone cover for example, in order to characterize the structure, composition and wear resistance of the coatings. The results could be divided into three groups: (I) tungsten-like, with very low oxygen content; (II) mixed phase and (III) tungsten oxide like, with oxygen content close to 75 at%.
Bestämning av bruttotemperaturexpansionskoefficient för Faradol 810
Detta examensarbete har genomförts på ABB Power Products/Instrument Transformers i Ludvika. Syftet med arbetet har varit att undersöka temperaturexpansionen för en isolerande olja som använd i produkten Capacitor Voltage Transformer (CVT). Oljans egen temperaturexpansionskoefficient var redan känd, men arbetets syfte var att bestämma en Bruttotemperaturexpansionskoefficient, med andra ord undersöka hur mycket de ingående komponenterna i en CVT påverkar den totala volymexpansionen inuti enheten.För att bestämma bruttotemperaturexpansionskoefficienten har ett prov i klimatkammare utförts. Provet bestod av två aluminiumkärl vardera med ett monterat mätrör. Det ena kärlet fylldes med olja och det andra kärlet med olja och kondensatorinnehåll motsvarande innehållet i en CVT.
Energikartläggning hos RostiGP i Gislaved
In today?s modern age, energy consumption has become a major issue, both from an environmental viewpoint and cost perspective. Because of a rapid technologic change and increased costs of production of electricity, the demand to develop effective methods for energy efficiency industries have grown.The electricity-intensive industries, such as plastic industry, the demand to reduce energy consumption has grown significantly over the past 10 years, which have led to the development of different methods to determine and locate energy-consuming parts in the industry. This also means being able to prioritize and organize activities in the industry.In this study the measurements of voltage, current, power and PF performance on injection molding machines (K-TEC 275 form Ferromatik Milacron in Germany) with a focus to locate, within a machine, various measures that could improve energy use in the plastics industry, in this case RostiGP in Gislaved. These measurements have been carried out with the help of a power quality clamp meter to carry out time logs of the machines for some time during normal word rate.
Ny stamstation i Yttermalung för anslutning av vindkraft : Nätstudie av olika utföranden i normal- och reservdrift
Since 2004, wind power has had the largest installation of new capacity compared to other energy sources in Sweden. Accommodating new wind power may require strengthening or rebuilding of the existing grid in areas where the grid is already loaded to maximum capacity. This master thesis examine the possibility of a new 400/130 kV substation in Yttermalung, Sweden, with a connection to the two neighboring regional grids in Dalarna and Värmland owned by Fortum. This substation would provide a new connection point to the Swedish transmission system as well as an interconnection of the two, currently separated, regional grids. Different expansion scenarios where a substation with and without series compensation or a phase shifting transformer (PST) to control active power flow were studied.
Kartläggning av begränsande faktorer vid fellokalisering med pulsekometod på mellanspänningskablar
I samband med att mellanspänningsnätet kablifieras ökar också kraven vad gäller fellokalisering. För att hålla avbrottstiderna i nätet korta är effektiv felsökning erforderlig. Detta arbete syftar till att kartlägga och redogöra för begränsande faktorer som finns vid fellokalisering med fokus på pulsekometoden. Uppdraget utförs tillsammans med Vattenfall Eldistribution AB.Det har uppdagats problem gällande fellokalisering på mellanspänningskablar med pulsekometoden. Ett flertal faktorer bidrar till denna problematik.
Avgång av lustgas från luftningsprocessen på Käppalaverket
The requirements for wastewater treatment plants (WWTP) are gradually increasing, partly because of higher incoming loads, which in turn require a more efficient treatment process. In parallel with environmental and economic goals there are also desires to lower energy consumption without compromising the wastewater treatment. Furthermore, there is a demand on WWTP´s to alter eutrophication in aquatic systems through better nitrogen and phosphorus removal. An increasing number of WWTP´s have acquired biological nitrogen and phos-phorus removal. A by-product of this type of biological treatment is the formation of nitrous oxide, which is a potent greenhouse gas.