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8597 Uppsatser om Power quality problems - Sida 32 av 574

En fallstudie över miljömålsarbetet på fyra länsstyrelser : Beskrivning och analys av det regionala miljömålsarbetet i Mellansverige.

The Swedish system of environmental quality objectives is a so-called MBO, Management By Objective and has the purpose to guide the Swedish society towards sustainable ecological development. The system involves the whole society from the parliament and the government down to individual citizens. At the regional level, it is the county administrative boards that are responsible for the work with the system of environmental objectives. At the County Administrative Board of Västmanland County, it is the environmental unit who is in charge of work with the environmental objectives and they want input for how to improve their work with the environmental objectives, both internally at the Administrative Board and externally with external parties.The main purpose and goal of the study is to present the work of four other county administrative boards regarding their work with the environmental quality objectives and to identify external parties? opinions of how they want the County Board of Västmanland county to work with them in this matter.The work is designed as a case study of four county councils, where the environmental objectives coordinators at the four county administrative boards were interviewed about their work with environmental quality objectives.

RCC-Jordfelsskydd, mätmodul för övertonsanalys

The majority of all power cuts that affects individuals and communities are caused by earth faults on the power transmission lines at 10kV and 20kV level [1]. If these power cuts could be eliminated, less disturbances and interrupts would lead to large amounts of money savings.Swedish Neutral has developed such a protection system. When an earth fault occurs power is injected into the neutral point of the transformer. The RCC (Residual Current Compensation) protection calculates a compensation current exactly 180 degrees out of phase to the fault current. Doing this, the voltage at the fault location becomes very close to zero, without affecting the power transmission.The protection system can only compensate automatically for the fundamental frequency (50Hz), and manually for the 3rd, 5th, 7th and 9th harmonics.

Sårbarhetsanalys av ett infrastrukturnätverk - Användning av nätverksteorier för sårbarhetsanalys av komplexa nätverk

The aim of this report is to examine the possibilities to use network theories to perform vulnerability analysis on complex networks. The scoop of this work is also to improve the possibilities to chart, analyze and present the vulnerability in a power grid. In this report it has been, using power outage statistics, possible to verify, that network theories can be used to evaluate the vulnerability of an infrastructure network. However further studies to establish values on how vulnerable a network is are needed..

Lönsamheten i vindkraft : en studie om den förväntade lönsamheten i landsbaserad vindkraft

This thesis analyzes the expected profitability in land based wind power plants. The expected profitability is calculated on the basis of a wind power project in Vartofta, Falköping. The information required to calculate the expected outcome is then concentrated to this project, which is in this thesis called project Näs. In project Näs they plan to build three wind power plants, with each an effect of 2 MWh. These wind power plants are very capital intensive investments with a long and uncertain payback time.

Nätanslutning av vindkraft : vindkraftsbranschens aktörers perspektiv på nätanslutning och tariffer

Wind power is a growing energy sector in Sweden. However, it still represents only a small part of the total electricity production, about 0.7%. In order to create good conditions and to facilitate the establishment of wind power in Sweden, the government has for example, created a national centre for wind use. The objective has been to reach the governmental goal, which is an expansion of wind power by 10 TWh by year 2015 compared to the level in 2002. The Swedish electricity market was deregulated in 1996 which refers to the introduction of a competitive market in electricity production and trade.

"Fallbacks" - betydelsen av vandringstid för Atlantlax (Salmo salar L.) som faller nedströms vandringshinder

In Lake Vänern, Sweden, there is an endemic population of Atlantic salmon (Salmo salar L.) that lives its entire life in fresh water. The salmon is hindered from migrating to its natural spawning sites in the northern part of the River Klarälven by nine hydro-electric power plants. None of the hydro-electric power plants have fishways so that salmon migrating upstream or downstream may pass. In the current situation, the upward migrating salmon are caught in a fish trap at the most downstream located power plant in Forshaga. From there, the salmon are driven in a truck, past eight power plants and released a few kilometers upstream of the eighth power plant at Edsforsen.

Optimerad styrning av kondensatorbatterier - Ny möjlighet att minska förluster med elektronisk brytteknik

Transmission of reactive power is well known to cause active power losses. Thus, newcomponents who can help minimizing these expensive reactive power flows are ofgreat interest to the power distribution companies. ABB Corporate Research hasdeveloped the first electronic power breaker. One possible application for thisbreaker is transient-free switching of capacitor banks. This could prove a usefuldistribution voltage complement to the switch-sync technique, mainly applied to transmissionvoltage level.

Fallet SAS : En studie i hur medial diskurs reproducerar maktförhållanden på arbetsmarknaden

Aim: The purpose of this study is to explore how the media through a certain discourse constructs a view of the labor market and the power relations between companies, unions and employees. The goal is to explore this through studying the media coverage of SAS? financial situation between September-December 2012 and our research question is the following: What view of the labor market and its power relations was constructed and reproduced by Swedish newspapers through their portrayal of SAS during September-December 2012?Method: This study analyses the findings with the help of questions based on theories of social constructivism, discourse, agenda-setting and power. A content and discourse analysis was compiled of 360 articles from five Swedish newspapers that addressed SAS and their situation from September-December 2012. The results of these analyses were further processed using power analysis and John Gaventa?s power cube.Results: In this study we conclude that the medial discourse constructs identities of the different actors and affect power relations between them, in favor of the company.

Meningen med livet : hur 15-åringar i en stor och en liten stad i Sverige ser på livskvalitet

There are many good reasons to ponder about what it is that makes life worth living. To observe and reflect on what it is that gives a person a good quality of life is arguably the essential core of social-work. The aim of this research was to investigate how 15-year old youths interpret quality of life. The key areas that we explored in order to meet the research aims were: what did the youths interpret as a good quality of life for a 15-year old and for an adult, how did they view their own quality of life, and did they think that the regional context (i.e. if one lives in a big city or in a small town) affects how one interpret quality of life.The studywas based on interviews with four boys and four girls.

Den gröna konsumentmakten - medborgarens ekologiska insats

The aim of this thesis is to form a theory of the green consumer power and to distinguish whether this phenomenon could indicate a movement toward the ecological citizenship. To do so, scientific theories regarding the responsibility of companies have been used, as well as the public choice theory, to link individuals as citizens to individuals as consumers. The motives of corporate environmental responsibility, along with consumers ability to bring pressure in different dimensions, are later drawn on as indicators applied to empirical information. The largest producer of ecological products in Sweden, Arla Foods, is employed as case study to explore if the green consumer power can and does exist. The ecological citizenship uses the ecological footprint, to define in what ways we can minimize our part of environmental degradation.The study seems to strengthen the theory, consumers do have a power to make companies go green and they tend to use it increasingly.

Huvudhalscancer och livskvalitet : Patientens skattning av livskvalitet innan och efter strålbehandling

Introduction: Each year 1200-1300 patients are diagnosed with head neck cancer. Treatment that involves radiotherapy can cause severe side effects for example trismus that affects quality of life.Purpose: To study health-related quality of life in patients who have undergone radiation treatment for head and neck cancer and participated in a intervention group who received training intended to prevent trismus or in a control group who received standard treatment.Method: This is a prospective study in which data is collected from 66 patients participating in a randomized study aiming to evaluate a training program to prevent trismus. Thirty three participated in the intervention group and thirty three in the control group. Both patient groups assessed health related quality of life (HRQOL) with EORTC QLQ C30 and QLQ-H&N35, at start and end of the radiation treatment, and at 3 and 6-months after completing radiation treatment.Results: There is no difference between the intervention and control groups regarding symptoms, functional status and global health, except for intake of nutritional supplements.  For both groups almost all scales measuring HRQOL deteriorated under the radiation treatment. However, 3 and 6 months after end of radiotherapy HRQOL had improved and had returned to the baseline values.

Labba i teori : Kan praktiska laborationer öka förståelsen av teoretisk datalogi?

Design for Six Sigma (DFSS) is a further development of the Six Sigma draft to carry through preventing quality measures in developing and designing of new products and processes. With increasing demands on enterprises development processes to be more safety and faster the need of DFSS arise as a product, process and service development concept in the organisations. Design for Six Sigma aims to improve and structure the development process of an organisation and consider the application of the innovation problem solving. The concept aims to leave the structure of the traditional Six Sigma concept and instead, from an innovative perspective, search for new solutions to existing problems. The concept constitute of a toolbox with a lot of quality tools that are divided into phases in a development model.

Den ständigt avvikande förorten : Medias diskriminering av förorten Andersberg

The emerging Swedish suburbs of the 1960- 1970s started out as a utopian vision: a new city for the modern people. Media presented a different view and emphasized the inhuman livingenvironment and the social problems of the suburbs. Nationwide there have been local attempts to avoid this negative publicity by adjusting identified suburban problems. Due to medial presentation the suburbs are still associated with segregation, criminality and social problems. The presentation of suburbs and immigrants affects not only the process of integration and the general public idea of integration processes, but also the individual perception of themselves and their living.

Vad är kvalitet i ledarskap? : Teorier, modeller och verkligheten

In this qualitative study the authors explores, by studying several quality-development models what quality in leadership is. The models are: Total Quality Management; SIQ?s model for customer-oriented organizational development; the EFQM excellence model; the ISO 9000:2000 standard; and Six Sigma. These models will be compared from Deming?s list for upper management; the Situational Leadership Theory; and the Contingency Theory.

Voltage Sags Indices and Statistics

Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.

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