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1265 Uppsatser om Fundamental frequency - Sida 1 av 85

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.

Robothandel ? En rättvis arena? -En litteraturstudie om Robothandeln med aktier

The purpose of the thesis is to demonstrate how high frequency trading affects the stock market. The growing high frequency trading is affecting the game plan on the financial markets and concerns have grown about the high frequency users intentions with their business. It is difficult to receive an overall picture of the subject because the lack of previous research and even the research that exist do not show the entire picture. The thesis contributes to the research through a comprehensive picture of the present debate as well as the previous research through a literature study. Our results showed that high frequency trading provides liquidity to the market, there is a statistical connection between high frequency trading and volatility, no price manipulation is being used and there is a need for a supervision of the high frequency trading..

Röst och hörselnedsättning : Akustisk analys av röst hos sju hörapparatsanvändare

A number of studies have been made to examine several aspects of voice production in individuals with different types of hearing impairments. Most of the studies were made to explore the impact that hearing aids have for people with severe or congenital hearing impairment. So far it has been confirmed that there are changes regarding voice production in these individuals. A group that has not been investigated regarding voice production to a larger extent are hearing aid users with an acquired hearing impairment. In the present study the voice production of seven individuals, four men and three women, with a moderate acquired hearing impairment is examined.

Bedömning av utländsk brytning och förståelighet hos personer med svenska som andraspråk före och efter en kurs i svenskt uttal

There is a lot of research made on second language (L2) learning (Jesney, 2004). However the relationship between foreign accent, intelligibility and acoustics within pronunciation tutoring is quite an unresearched area (Thorén, 2008). The aim of the study was to analyze how a course in Swedish pronunciation affected foreign accent, intelligibility and acoustics among L2-learners of Swedish. A total of 41 people participated in the study: 16 L2-learners, 4 native Swedish speakers consisting a control group and 21 perceptual assessors with Swedish as native language. The L2-learners foreign accent and intelligibility were rated by the listeners before and after a course in Swedish pronunciation on an eight-point Likert-scale.

Frekvens och spanningsskalning i en inbyggd mikroprocessor; for att mojliggora implementationen av schemalaggning med stod for dynamisk frekvens- och spanningsreglering for energihantering.

Minimizing power consumption is a critical part of many embedded design projects. Thechallenge is to limit the power consumption of the system and at the same time providesatisfactory service to the user. With regards to microprocessors, the main way of limiting powerconsumption during program execution is to adjust the frequency and the voltage at which theprocessor operates.To enable the implementation of real-time scheduling with support for dynamic voltage andfrequency scaling, an exhaustive study of the Freescale i.MX31 embedded microprocessor isperformed. Specifically, the power consumption relationship to all relevant frequency andvoltage settings is investigated. In addition, to enable frequency and voltage scaling in a real-timeenvironment, a complete timing analysis of proposed voltage and frequency scaling methods isperformed and their suitability for use in real-time systems is evaluated.To integrate voltage and frequency scaling capability into OSE RTOS, a software module hasbeen developed for this operating system.

Frekvensreglering i det nordiska kraftsystemet

Svenska Kraftnät is (together with the other transmission system operators of the Nordic power system) responsible for keeping balance between the generated and demanded power in the Nordic power system. Spontaneous load variations and system disturbances, however, lead to power imbalance followed by frequency variations. The frequency deviations can be limited to an acceptable level by the spinning reserve, mainly by hydro power control. But there are also other system properties which have a great influence on the frequency and system stability. The frequency and voltage dependence of the loads have a direct influence on the power balance.

Burkaförbud : Rättfärdigad restriktion eller brott mot de grundläggande friheterna och mänskliga rättigheterna?

The fundamental freedoms and human rights is something the countries, and its citizens, of theEuropean Union more or less take for granted. However, in recent years these rights have become atopic of discussion in the way that a debate about the Islamic headscarves has developed. Thisdebate has resulted in that a number of countries, including France, have taken legislative measuresto ban clothing that fully covers ones face. Out of these bans a discussion has arisen concerning thefundamental freedoms and human rights. These burqa bans, as it is labeled in the pubic debate, havebeen accused to wrongfully limit the individuals freedoms and human rights.This study therefore has the aim to analyze these burqa bans in relation to the European Union,United Nations and the Council of Europe?s general declarations concerning the fundamentalfreedoms and basic human rights.The main result of this study shows that these bans in fact is not a proportionally restrict in thefundamental freedoms and human rights.

Efficient Frequency Grouping Algorithms for iDEN

This Master?s Thesis deals with a special problem that may be of importance when planning a frequency hopping mobile communication network. In normal cases the Frequency Assignment Problem is solved, in order to plan the use of frequencies in a network. The special case discussed in this thesis occurs when the network operator requires that the frequencies must be arranged into groups. In this case the Frequency Assignment Problem must be solved with respect to the groups, i.e.

Effekten av frekvenskomprimerande hörapparater på taluppfattningen hos patienter med grava diskantnedsättningar ? En experimentell studie

A pilot study conducted on four patients, which we received from the Sahlgrenska University Hospital, who were all potential candidates for a cochlear implant. We fitted our test subjects with a pair of frequency compressing hearing aids called Phonak Naida V SP during the study and let them evaluate them for about seven weeks. Measurements made with monosyllabic words throughout the study showed significant differences in speech perception (p?0.05) compared to their regular hearing aids in 3 out of 4 cases. De-activation of the frequency transposed function showed significant decreases in 3 out of 4 cases compared to when it was activated.All test subjects were satisfied with the new hearing aids and chose to keep using them at the end of the study..

BIM i förvaltningsskedet - Nyttan för fastighetsägare

The use of Power Line Communication, PLC, as a communication solution for Automated Meter Reading, AMR, is popular by utilities in Sweden and other parts of the world due to demands of accurate and fast meter reading. However the use of the electrical grid as a communication medium is complex and sometimes problematic. This report handles some of the issues and problems that are important to understand when using the grid as a communications medium. Focus is mainly on investigating high frequency distortion in the Kristianstad power grid own by C4energi caused by a frequency converter. Measurements on site are done to investigate signal damping in the grid, different configurations for the frequency converter and signal strength of the PLC-system.

Värdegrundens betydelse för arbetsgivarens attraktivitet

During the past decades the competition for skilful employees has increased and companies and organizations compete to attract the right people. The Swedish municipalities and country councils need to recruit 420 000 new employees before 2020, but have a limited budget to promote themselves as attractive employers. To find a solution, many of the municipalities have started to work with fundamental values to become more attractive employers and to inspire employees to use word-of-mouth to recommend them. There are no empirical studies of how successful this strategy is, and the purpose of this thesis is to show if there are significant correlations between the fundamental values, the employer's attractiveness and word-of-mouth. The results of the study are based on a survey with 1996 answers from employees in three different municipalities in Stockholm, Sweden.

Styrning av artikelplacering i lager

This thesis deals with the field of warehouse management, focusing on frequency control of stock. The purpose of the thesis is to reduce the warehouse staff mileage by placing an article based on its number of picks, i.e. how frequently it gets picked. In order to achieve relevant results the following four questions have been answered in the thesis: How should the articles be placed with regard to the picking frequency?Which factors, if any, needs to be addressed beyond the picking frequency when articles are placed based on frequency?Can the present picking system be improved?Is frequency placement with regard to the picking frequency profitable to implement for the company?The thesis is based on literature studies and on the data that has been collected from the company?s business system.

Analys av högfrekvensstörningar och elnätskommunikation i distributionsnät

The use of Power Line Communication, PLC, as a communication solution for Automated Meter Reading, AMR, is popular by utilities in Sweden and other parts of the world due to demands of accurate and fast meter reading. However the use of the electrical grid as a communication medium is complex and sometimes problematic. This report handles some of the issues and problems that are important to understand when using the grid as a communications medium. Focus is mainly on investigating high frequency distortion in the Kristianstad power grid own by C4energi caused by a frequency converter. Measurements on site are done to investigate signal damping in the grid, different configurations for the frequency converter and signal strength of the PLC-system.

Att projektera för demontering. Undersökning av stomsystem

The use of Power Line Communication, PLC, as a communication solution for Automated Meter Reading, AMR, is popular by utilities in Sweden and other parts of the world due to demands of accurate and fast meter reading. However the use of the electrical grid as a communication medium is complex and sometimes problematic. This report handles some of the issues and problems that are important to understand when using the grid as a communications medium. Focus is mainly on investigating high frequency distortion in the Kristianstad power grid own by C4energi caused by a frequency converter. Measurements on site are done to investigate signal damping in the grid, different configurations for the frequency converter and signal strength of the PLC-system.

Undersökning av lönsamhet inför fastighetsförvärv

The use of Power Line Communication, PLC, as a communication solution for Automated Meter Reading, AMR, is popular by utilities in Sweden and other parts of the world due to demands of accurate and fast meter reading. However the use of the electrical grid as a communication medium is complex and sometimes problematic. This report handles some of the issues and problems that are important to understand when using the grid as a communications medium. Focus is mainly on investigating high frequency distortion in the Kristianstad power grid own by C4energi caused by a frequency converter. Measurements on site are done to investigate signal damping in the grid, different configurations for the frequency converter and signal strength of the PLC-system.

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