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3983 Uppsatser om Electrical distribution systems - Sida 5 av 266

"Den som är satt i skuld är icke fri" : En studie om de svenska elnätsföretagens kapitalstrukturer

Title: Co-operative, prevent or complement? - An essay on the relationships between control systems. Authors: Kim Eriksson and Victoria KarlssonPurpose: The essay aims to describe the relations between control systems and how they related to each other, based on an operationalization of the control systems. Research question: What are the control systems relations to each other? With regards whether control systems co-operative, prevents and/or complement each other.Theoretical framework: The essays theoretical framework is based on Malmi and Browns (2008) description of five different control systems and control mechanisms associated with each control system.   Research methodology: The method was based on three different data collection methods. These methods were observations, documentation, and semi-structured interviews.Conclusions: It is concluded that the control systems has comprehensive relations. Control systems have more, than one, relation to each other..

Självförsörjande elgenerering : Kan Orust bli självförsörjande på förnybar el?

Orust Kretsloppsakademi is a nonprofit organisation, with a goal of annually generate the same amount of electrical energy that is consumed. Orust is an island on the west coast of Sweden, north of Gothenburg. The population of 15 000 reaches 40 000 during summer, due to the large amount of vacationer. The total electricity demand is 174 GWh a year with a maximum power need of 32 MW. This report presents an analysis for the plausibility of their plan and from a power system stability perspective, the effects on the electrical grid.The conclusion is that the restraints for development of power generation from wind, solar and wave generation, are the power systems capability to transfer power, primarily in the transformers of the grid.

System, stabilitet och makt - informationsdiskursen i Organizing Knowledge

TitleSystems, Stability and Power. The Discourse of Information in Organizing Knowledge.AbstractThe aim of this Master's thesis is to inquire into the consequences of an unequal distribution of power between information discourses in the field of knowledge organisation. A deconstruction of Jennifer Rowley's and John Farrows introductory textbook Organizing Knowledge from 2000 is related to the major discourses of information in LIS. Questions posed in this study are: What meaning is ascribed to information in the material studied? Which information discourses are given a dominant position? Which are excluded? and: How does this affect the construction of the library and information science student's identity, in relation to practices of knowledge organisation? The theoretical framework is provided by Ernesto Laclau's and Chantal Mouffe's theory of discourse and combined with techniques for text analysis originating from the work of Norman Fairclough.The analysis reveals a strong domination of a cognitive discourse of information that underlines the importance of information systems for the organisation of knowledge.

Hemautomation : Spara energi genom att automatisera hemmet

In today's society there is a significant focus on energy efficiency. Despite this, people leave lamps, televisions and computer screens etc. powered on unnecessarily. The goal of this project is to build a simple prototype for home automation where a user, via an application on a mobile phone, can switch on and off the power of an electrical products in the home and as well as being able to check whether such products are switched on or off. The prototype will also collect data on power consumption for these electrical products.

Vindkraft för uppvärmning

This final thesis contains three major parts, which all have been time demanding:* Designing and construction of a small wind turbine.* Designing and construction of an electrical system.* Thesis with fundamental facts about wind, wind power and design.The thesis contains basic theory in wind power and the energy systems it can be combined with. Different types of wind turbines, which components they consists of and important issues to consider when designing is also mentioned. In the end of this report the technique of our wind turbine will be presented. In the end you can also read about our experiences during the time of designing and construction..

Samverkande, motverkande eller kompletterande? : En uppsats om relationer mellan styrsystem

Title: Co-operative, prevent or complement? - An essay on the relationships between control systems. Authors: Kim Eriksson and Victoria KarlssonPurpose: The essay aims to describe the relations between control systems and how they related to each other, based on an operationalization of the control systems. Research question: What are the control systems relations to each other? With regards whether control systems co-operative, prevents and/or complement each other.Theoretical framework: The essays theoretical framework is based on Malmi and Browns (2008) description of five different control systems and control mechanisms associated with each control system.   Research methodology: The method was based on three different data collection methods. These methods were observations, documentation, and semi-structured interviews.Conclusions: It is concluded that the control systems has comprehensive relations. Control systems have more, than one, relation to each other..

Energivinst vid hybridisering av hydrauliskt system

Today's high oil prices and more stringent environmental requirements have led to that manufacturers of mobile construction equipment try to make their products more energy efficient. With this in mind a project about hybridization of hydraulic systems has been formed. The purpose of this project was to analyze the savings that can be achieved by hybridization of hydraulic systems. A reach stacker truck (Kalmar DRD450-80S4XS) were simulated in some load cases with conventional hydraulic systems and with three types of hybridized hydraulic systems. Different parts of the hydraulic systems were also analyzed separately.

Distribution och försäljning av kvalitetsfuru : en fallstudie

The purpose of this study is to analyse how a distribution and sale-network for quality softwood lumber should be designed to fit sawmilling companies? business concepts, and at the same time satisfy customer needs regarding delivery time and quality aspects. This thesis work is a case study based on a sawmilling and retail company in Sweden. AB Karl Hedin is a private owned sawmilling company with 500 employees. The company?s turnover is 1500 million SEK, it includes 4 sawmills, 16 builders merchants stores and a packaging company.

OSE och Linux : En studie om prestanda

There are some key elements which distinguish a general operating system, such as Linux, from a Real Time operating system, such as OSE. The later belongs to the category of soft Real Time systems while Linux is a general operating system, with significantly improved real time properties after version 2.6. These improvements make it interesting to compare the two systems.When comparing two operating systems, there are a number of issues which have to be considered. One way to measure the performance of the systems is by studying the time consumption for the same functionality and hardware.During the study, the items that appeared as the most important for the performance of the systems, were: process primitives, system primitives, interprocess communication, context switches and interrupt latency.This work demonstrates that it is possible and reasonable to do performance testing on two different operating systems. The implemented tests cover a number of basic functionalities, which appeared to be the most crucial ones for the performance of the systems..

Beräkning av värmeförluster och energieffektivisering av elbussar

The ?civilized? world is in need of fossil fuel in order to function. Hybricon AB is a company in Umeå that is developing a technology that hopefully can reduce parts of this need. They are currently testing their two electrical busses (with Hybrid backup) in city traffic on the roads of Umeå in cooperation with the county of Umeå.                               The busses are originally diesel-busses, but the diesel motor has been replaced with two electrical hub-motors with a power of 145 kW each that are powered by batteries.The batteries are charged at the end station after each route. In case the batteries should run low on capacity during driving, they can be recharged by the so called genset.

En vindkraftparks inverkan på Gävle Energis elnät

The effects from a planned wind farm on the grid utility Gävle Energis electrical grid have been studied. The wind farm is planned to be built in the forest 15 km north of Gävle and will have 23 turbines with rated power from 2 to 2.5 MW, resulting in a total installed power between 46 MW and 57.5 MW. The grid connection will be made at 70 kV. The aim of the analysis was to determine what effects the wind farm would have on the power grid in the form of electrical disturbances (flicker etc.), need for new investment and raised operational cost. To allow the connection of the wind farm technical solutions (new lines, power stations and grid reinforcements) have been constructed.

Hur miljövänlig är dagens optikerbutik, och hur miljövänlig kan den bli?

SUMMARYEnvironmental issues are currently a hot topic of debate. Studies within the optics branch have not specifically been conducted previously, so the aim of this study was to determine the extent of environmental-awareness specifically within this branch.A survey, consisting of questions relating to environmental issues, was distributed to 100 randomly-selected opticians in Sweden. Of these 100 surveys, 64 were returned and showed a varied branch-engagement for environmental issues.Results of this survey showed that opticians were best in sorting newspapers, magazines, other paper and hazardous waste. Metal and rigid plastic were not sorted to any larger extent.Choosing environmentally-safe products was not so popular and only six stores always do this. 25 shops turn off electrical machines and equipment over night; while the majority of the remaining stores leave the machines on during the night.27 stores did not know if their electrical company provided ?green electricity?.Results showed that there is a lot of work to be done in making the stores more environmentally friendly.

Utökning av mätområdet för turbinverkningsgraden på avgasturbo

The Goal with this Master of Science thesis is to expand the possible turbine efficiencymeasurements on an exhaust turbocharger. It was done as a part of the CICERO competencecentre. To feed the turbine with air a special flow rig has been used. Instead of loading theturbine by just restricting the compressor flow a docking system for an electrical dynamometer isdesigned to use the dynamometer as an additional loading source. By using an electricaldynamometer as loading device for the turbine, measurements are not depending on compressorperformance.A large part of the work consists in designing accessories for the dynamometer.

Effektiviseringspotential inom industrisektorn : Energibesparing vid frekvensstyrning av centrifugalpumpar ? en fallstudie

The project was performed at SiemensIndustry Drive Technologies with theobjective to provide actual values forthe energy savings potential withinSiemens scope of practice.In Sweden the electrical drives standfor about 30 % of the total electricityconsumption and about 60 % of theelectricity consumption within theindustry. During the pre-study phaseelectrical drives with pump applicationswere identified as large energy users.Because of this a case study at one ofSiemens customers, Stora Enso Fors wasperformed. The system that was evaluatedduring the case study was a throttledsystem with a centrifugal pump forpumping pulp.The results yielded that a saving ofover 50 % could be achieved by replacingthe throttle valve with a variable speeddrive, a frequency converter. Thepayback period was two years and twomonths and the present value for thetotal life cycle cost of the variablespeed system was 662.566 SEK lower thanfor the throttled system. As aconsequence, Stora Enso Fors is advisedto invest in a frequency converter forregulation of the system.The general conclusion is that a focuson system efficiency is the mostimportant factor in energy efficiencyprojects and that the system regulationmethod has a large impact on the overallsystem losses and hence its efficiency.Energy efficiency potential forthrottled systems with centrifugal pumpsis large and significant economicalsavings can be made through investmentswith short payback time..

Electrolux och patenten. En studie av Electrolux patentstrategiska agerande 1950-1970.

Application Lifecycle Management (ALM) is a genre of computerized systems which allows system development corporations to efficiently and more easily manage, maintain and handle the applications lifecycle. These ALM systems have a wide variety of tools which can be integrated to enable and support collaborative work, while they act at the core of the organisation. Todays ALM systems support flexible system development methods throughout the entire development process. This paper focuses on a case-study of a Swedish business- and technology corporation and their use of two ALM systems with an aim to unravel the differences between these systems and their functionality to serve as a basis for decision making regarding their utilization of best practice with their ALM-Systems. Meanwhile we studied their approach to ALM systems to see if they were using them according to the initial idea of ALM systems.

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