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8597 Uppsatser om Power quality problems - Sida 4 av 574

Effekten av höghöjdsvistelse på anaerob arbetsförmåga

Syftet med denna studie var att undersöka om vistelse på hög höjd påverkar den anaeroba arbetsförmågan. Sex aktiva universitetsstudenter, fyra män och två kvinnor, deltog frivilligt i studien. Expeditionen till Nepal varade i 40 dagar och under den perioden sov och vandrade försökspersonerna mellan 1400 och 5100 meter över havet. Före och efter expeditionen genomförde försökspersonerna ett anaerobt wingatetest där peak power, average power, minimum power and power drop uppmättes. Resultatet visade en signifikant sänkning av average power efter den genomförda expeditionen på hög höjd, med ett medelvärde på 8.44 ± 0,84 w/kg före expeditionen och 7.81 ± 0,87 w/kg efter expeditionen.

Hur påverkar en ökad andel solceller Umeå Energis elnät? : ? En utredning med fokus på spänningsvariationer och osymmetri inom landsbygds- och tätortsnät vid en- och trefasanslutning av solcellsanläggningar

A good power quality can be an important prerequisite to achieve a sustainable society. Scandinavia's electrical system is in many respects superior, and Sweden has a fossil free electricity generation at 97 % and a reliability of electricity distribution at 99.98 %. Meanwhile, the EU has an ambition to expand the electricity market in order to achieve a joint trading business across Europe. This cross-border market will result in a large proportion of fossil energy sources integrated into our electrical system, which also leads to an increased need for renewable electricity production in Sweden. One part of this development is to increase the share of renewable micro generation that is locally or regionally connected to the power grid.

Faktorer som påverkar vindkraftsutbyggnaden

Wind power is expanding rapidly in Sweden. Increasing amounts of wind power sets higher requirements on balancing power and grid expansions and would affect the whole Swedish electricity system. The aim of this report is to examine the factors affecting the wind power expansion in Sweden. How many wind power plants projects will obtain building permissions and what costs and revenues can be expected? How much balancing power will be required and does a changing geographical distribution of the wind power plants reduce the need of balancing power?A survey of the county board?s official applications has been made and out of all the applications, corresponding to 80 TWh produced per year, about half of the applications are expected to obtain a permit with a major portion of them located in the north of Sweden.Especially older wind power plants, deriving revenue from Nord pool, find themselves today in a complicated financial situation.

Kvalitetsbristkostnader: En kvalitetskostnadsuppföljning för produktion och eftermarknad. : En fallstudie vid Huddig AB

All companies wants? to be as profitable as possible. The company in question is one of the leaders in it´s field in Sweden. In order to increase profits as much as possible it is important to identify and eliminate eventual quality defect cost as far as possible.This study was performed in Huddig AB, and the purpose of this study is to try to develop a routine for monitoring the quality defect costs, and to improve communication and create feedback between production and aftermarket.In addition to an extensive literature review on quality defect costs most of the work have been conducted at the company. Own observations and interviews have been done with the staff to get a picture of the current situation and to try to come up with improvement proposals.During the study it was proved that much of the quality defect costs in essence, derived from the production, which is seen as positive because it is the easiest part of the company to improve.

USA som hård, mjuk och smart makt -En studie av amerikansk utrikespolitik i mellanöstern

This essay is built upon the thoughts of Joseph S. Nye concerning power, and the different ways of exercising that power. The characteristics of Nye's theories are the thoughts about the second face of power, or what he describes as the soft power. The essay seeks to examine what kind of power the US has been in their work for non-proliferation and democracy promotion in the Middle East. It also seeks to find what it is that makes the US to choose to exercise the specific powers.

Systematiskt kvalitetsarbete på förskolan : Hur förskollärarna uppfattar och hanterar det systematiska kvalitetsarbetet

Systematic quality work in preschool ? How preschool teachers thinking and working with systematic quality work The purpose of this study was to investigate how Swedish preschool teachers thinking and working with systematic quality work. All Swedish preschools are required to work systematically with quality. This involves several steps that follow each other in a specific order. It includes following up, documenting and evaluating preschool activities.

Elkvalitéproblem vid varvtalsstyrd motordrift i industrimiljö

Övertoner orsakade av varvtalsstyrda motordrifter ger problem i industrisystem. Syftet med studien är att identifiera problemen och ge rekommendationer för att undvika dem. Studien utfördes som examensjobb på KTH för konsultföretaget Ramböll. En litteraturstudie i ämnet kombinerades med elkvalitémätningar på drifter hos Sandvik Mining.Elkvalitéproblem orsakade av varvtalsstyrda motordrifter kommer till stor del av att frekvensstyrningen ger olinjärt strömuttag som, om nätet inte är tillräckligt starkt, påverkar spänningskvalitén. Problemen kan vara driftstopp, störd utrustning och ökat slitage på utrustning för att nämna några.Denna studie visar att vid ändringar i system innehållande övertoner kan framtida övertonshalter approximeras för vissa fall.

The Way We Produce : Möjliga kvalitetsförbättringar på Atlas Copco

The purpose of this master?s thesis was to find problems that occur in the production line at Atlas Copco Rocktec Division, in order to decrease the costs of defect in quality. When the problems were distinguished, the authors ought to choose the problem with the highest improvement potential. One request from the constituent at Atlas Copco Rocktec Division was to connect the improvement to the document The Way We Produce. The document provides information and values about Atlas Copco and consists of 10 principles to be able to reach their vision.

Vindkraft eller kärnkraft - En jämförelse

The scope of this project is to make a comparison of costs associated with wind and nuclear power in order to decide which one of these is the most suitable in the case of an increased demand for electricity. It is also investigated if there are other factors that can influence the choice of energy source.An average cost is calculated in terms of kronor per kilowatt-hour (SEK/kWh) using cost of investment, operation & maintenance and taxes & subsidies. Total investment cost is recalculated to production cost using the annuity method at three different interest rates (6%, 9% and 12%).The comparison is made between three cases of wind power and two cases of nuclear power. For wind power there are two ocean-based (300MW and 100MW installed capacity, respectively) and one land-based (60MW) wind farm. For nuclear power there is one EPR-reactor (1600MW) and one AP1000-reactor (1100MW).

Pallhantering på Findus - Flöden , problematik och alternativ

The purpose of my task was to map the pallet flows at Findus and put together as well as analyze the problems. My work has also included finding out what alternatives there are to the present pallet exchange system and suggest measures to reduce the problems.The problems can be divided into poor quality and hygiene issues. The poor quality, for instance poor strength is due to arbitrary judgements and the fact that there are companies that make a system of manufacturing forged pallets of an inferior quality compared to the EUR-pallets. These pallets are marked with stamps more or less similar to the EUR-mark and taken into the exchange system. Of course there are rules how to judge a pallet but these rules are many and sometimes indistinct and there are a lot of marks to keep track of.The most dangerous part is when the pallets lack the prescribed carrying capacity.

Utredning av frekvensregleringens påverkan på mekanisk utrustning i en kaplanturbin

As a consequence of increasing wind power installations in the Nordic grid the last years, the need for regulating power has become larger. In the Nordic grid, regulating power is mainly provided by hydro power. One part of the regulating power is called frequency control, which ensures that the grid frequency is stable and close to 50 Hz.However, setting the turbine into frequency controlled operation may cause stress and wear of the components in the mechanical control system. Frequency controlling implies large and frequent servo forces and longer travelling distance of the sliding bearings in the Kaplan turbine.Based on one selected Kaplan turbine, Selsfors G1, measurements and MATLAB calculations have been performed in order to determine forces and movements of the linkage system. With these forces and movements as input, stresses and fatigue have been determined as well as sliding distances, bearing pressures and wear of bearings during a typical lifetime of 40 years.The results indicate that no severe wear exists on the bearings during 40 years of service.

Livskvalitet och rehabilitering för män och kvinnor med diagnostiserad hjärtsjukdom : en litteraturstudie

The aim of the study was to describe how women and men with diagnosed heart disease experience their health-related quality of life and what differences there is between genders in their quality of life and also describe problems after receiving the diagnosis. The study also aimed to describe rehabilitation of patients with heart disease. The study was a descriptive literature study based on scientific articles. It emerged that both women and men with heart disease experienced lower quality of life compared to normative data. There was a significant difference between women and men both one year and three years after receiving the diagnosis heart disease, which showed that women experienced lower quality of life than men.

Klosjukdomar hos hund : en litteraturstudie och en fallstudie i den Svenska Riesenschnauzerpopulationen

Various problems with nail disorders have been noticed in the Swedish population of Giant Schnauzer, but the frequencies of these problems are unknown. This could be due to the fact that bad nail quality has several differential diagnoses and lack of diagnostic criteria and diagnostic codes for nail disorders. The main purpose of this study is to review different types of claw defects and diseases of the nail bed in dogs, and to classify and evaluate the proportions in the Swedish Giant Schnauzer population. The nail is a specialized part of the skin. The quick will strengthen and protect the third phalang against the surrounding.

Gemensamma kostnader : Det verkliga utfallet

The aim of this report is to develop an improved basis for calculation of common costs as well as to create a support, showing which steps can be taken for improving the future monitoring at NCC Hus in Karlstad.The objective of this report is to improve the quality of the process of quoting by verifying current key numbers, production of new key numbers and to identify the problems affecting the monitoring of projects.The objective is also to provide suggestions of actions improving quality assurance at NCC Hus in Karlstad..

Var det värt det - Hur prisnivå påverkar uppfattad kvalitet, prisvärde och kundnöjdhet

The purpose of this paper is to examine the effect that price has on quality expectations and customer satisfaction and how price fits into a customer satisfaction model. An experiment in which participants are subject to scenarios of a high or low quality flight are used to test the hypotheses. The analysis shows that perceived quality has a bigger impact on satisfaction than price. Furthermore, price and quality do not affect customer satisfaction independently of each other. The importance of value compared to quality changes whether the actor is a high or low price actor.

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