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6095 Uppsatser om High-performance concrete - Sida 11 av 407

Konvertering från luft till vätskekylning av elektronik

A Swedish electronics company wants to make the cooling of one of their electronic components more efficient. They propose that a retrofit liquid cooler is the way to achieve this goal. The current air cooling has high energy cost due to the high amount of power needed to power fans and heat exchangers. Using high volumes of air for cooling also leads to noise pollution. The conversion from air to liquid cooling would possibly make the operation of the electronics more cost efficient and less noisy.The purpose of this project is to theoretically evaluate different concepts of drawing the heat generated by the electronic component in to a fluid, using numerical calculations in Matlab and FEM simulations in ANSYS.

Acceptansgränsen för solceller i lågspänningsnät : Kan den ökas?

Microproduction, also called distributed generation, is something that has become more and more popular in the electric grid. Microproduction can however lead to unacceptable performance if several units are installed in the same low voltage network. It is therefore good to know a limit where the performance of the low voltage network becomes unacceptable based on given parameters. This limit is usually called hosting capacity.In this report the hosting capacity with respect to voltage and current have been studied in three low voltage networks which are located in Falu Elnäts concession area. This has been done by simulations in a GIS-program where critical times of the grid have been simulated.

Enklare korglutning

This project was led on behalf of Bombardier Transportation in Västerås, Sweden, incollaboration with KTH Stockholm and EPFL Lausanne. This project is connected to thedevelopment of a new and simplified tilt system for rail vehicles.Growing competition from other means of transportation has forced railway companiesthroughout the world to search for increased performances.Travelling time is the mostobvious performance indicator that may be improved by introducing high-speed trains.They require very large curve radii and long transitions curves not to impairridecomfort, another performance indicator. Building new tracks adapted to high speedtrains is very costly and can only be justified where the passenger base is large.Trains with the capability to tilt the carbodies inwards the curve is a more cost efficientalternative. The tilt inwards reduces thelateral force felt by the passengers allowing thetrain to pass curves at enhanced speed with maintained ride comfort but increases thefrequency ofmotion sickness.The benefits of tilting trains are improved speed capability in curves and enhancedpassengers comfort, but at higher buying and maintenance cost. As the conventionaltrains increase their speed in curves, the performance advantage of tilting trains isreduced while their prize is still kept significantly higher and constant.

Long-Term performance of Swedish IPOs - 1990-2002

We have performed a study much similar to Ritter?s (1991) about long-term aftermarket performance of IPOs on the Swedish market during the years 1990 to 2002. The study resulted in evidence for that Swedish IPO do underperforms their benchmark-portfolios during a 36-months period. Though, the grade of underperformance depends of the chosen benchmark. The study is mainly focused on a particular benchmark, a portfolio of non-issuing firms matched by size and sector.

Ledarskap, kommunikation och målsättning som motivationsfaktorer : en fallstudie på Fresenius Kabi i Uppsala

It's not a secret that most companies strive to get such a high economic return as possible. To successfully engage in a profitable enterprise, there are many elements that come into play. An important element is the motivation of the employees and their work performance. Work motivation is a key factor for the employees to improve their performance and therefore determinant for the successes of the company.This work is a case study in the production at Fresenius Kabi, Uppsala. The work is based on an employee survey that they fill out once a year and the aim is to develop a deeper understanding for these questions and how the employees see on leadership, communication and goal-setting as motivators and how these factors works in the company today.To get this deeper understanding I have used a qualitative approach.

Kiviksgraven : analys av dess historia och framtid sett utifrån bevaringsfrågor

This essay focuses upon the Kivik monument and its conservation difficulties, since its discovery at 1748 until modern time. The Kivik monument is found in southeast of Scania, and dated within the Bronze Age period. The perspective of the conservation on the monument has merely been on the monuments inner cist of stone and the rock carvings on the cist-slabs. When the monument was first archaeological examined at 1931, its sizeable cairn (75 m in diameter) had almost vanished and the cist was sheltered by a casing of concrete and metal roof. Between 1932 and 1933 the monument has undergone a large-scale restoration, and this criticized restoration resulted in a low antiquarian value with the responsible authority.

Topprestation

To achieve peak performance as a young elite athlete, there are many psychological andphysical factors that have impact on human?s performance. Factors that affect theperformance interplay and interact must work to maintain ability to perform at its peak.The purpose of this study is to examine the factors that contribute to peak performance.Data collection method of the study has been done with a questionnaire, addressed toyoung elite athletes on a secondary school. It was 87 respondents who participated onvoluntary and anonymously conditions. The respondents consisted of men and womenbetween 16 and 19 years old.

Nominalfrasers inverkan på återvinningseffektiviteten i ett probabilistiskt IR-system

The purpose of this study is to examine the difference between three query strategies with respect to retrieval effectiveness. The thesis aims at examining how two types of noun phrases containing a modifier to the head word, which is a noun affect the retrieval performance with regard to recall and precision. The noun phrases in the thesis are of two types: 1) noun phrases containing a modifier to the head word (which is a noun) and which are not dictionary phrases (NF) and 2) dictionary phrases. Both types of noun phrases in this thesis contain at least two words. The queries were executed in Query Performance Analyser, QPA, containing the InQuery system and a sub collection of TREC-Uta documents with its topics.

Det norska energideklarationssystemets konsekvenser för äldre byggnaders karaktärsbärande värden

Roughly 130 000 dwellings have been officially registered since Norway as of summer 2009 passed their bill ?Energimerkeforskriften? on energy performance certificates in buildings. The main objective is to decrease the total amount of national energy consumption by producing a methodology of calculation of the integrated energy performance of buildings as well as proposing cost effective measures to lower each building?s energy consumption. As the measures should not contravene nor be incompatible with the intended quality and character of the building, the ?Energimerkeforskriften? exempts buildings that due to their historical and cultural values are protected cultural heritage legislation. The current system offers a couple of professional certification alternatives, but when two online semi-automatic methods developed specifically for non-professionals are by far the most used, and since the methods of calculation primarily have focused on modern building materials and construction, the rest of the historical building stock stands literally unprotected by incorrect performance certificates and high-risk energy efficient measures. The objective of this thesis is to identify if the current Norwegian energy certificate system poses a threat to older buildings.

Jämförelsestudie för tre olika metoder att beräkna genomstansning i betong : Skillnader i genomstansningskapacitet för metoderna i BBK04, EK2 och BHB

Before the European construction standards were introduced in January 2011, it was mainly themethod in BBK04 that was used for calculating punching capacity in concrete structures, and in lesscommon cases the method in BHB. The method of BBK04 is easy to use and have had the samestructure since the first was published in 1979. The Concrete handbook method (BHB) where usuallyonly used when a higher punching capacity was needed and the cross-sectional height where fixed,calculations using this method entails more work, but will in return usually give a higher capacity. Italso allows the use of shear reinforcement to increase the cross-section capacity. The method ofcalculating punching shear in EC2 differs largely from the methods of BBK04 and BHB.

Expansion av sökfrågor med Svenskt OrdNät som termkälla

The purpose of this Masters thesis is to examine the performance of queries that are expanded by synonyms and hyponyms from Svenskt OrdNät, the Swedish version of the Princeton WordNet. Four different types of queries were constructed: a baseline query S1, the baseline query expanded with synonyms S2, the baseline query expanded with hyponyms S3 and finally the baseline query expanded with the synonyms and hyponyms used in S2 and S3. The terms for expansion were picked by hand. The queries were executed in the Query Performance Analyser QPA, a tool used in IR education and in experimental IR research for analysing and comparing the performance of individual queries. 20 topics from the test collection GP_HDINF were chosen for the experiment.

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..

Metodutveckling av självskattningsformulär för prestationsmätning av flygledare innan skiftstart

This paper was part of the ongoing cooperation between the Swedish Civil Aviation Authority and the Department of Psychology at Lund University. The purpose of this study was to develop a self-report measure regarding human factors, for the air traffic controllers to fill out before they start their working shift. This in order to aid the team leaders in their judgment regarding the air traffic controller's ability to perform at the right safety level. The self-report measure would also serve as an aid for the air traffic controllers who have a responsibility regarding their own performance. If successful this self-report measure would make it easier for the air traffic controllers to be alert regarding certain factors that can have a large impact on their performance.

Balanced Scorecard utifrån ett hållbarhetsperspektiv : En studie av statliga företags hållbarhetsrapporter och dess möjlighet till integrering med ett Balanced Scorecard

Today, companies work with issues concerning Corporate Social Responsibility (CSR). A higher demand from customers and other stakeholders as well as an extended legislation are great reasons. Framework and guidelines for sustainability reporting has been developed which includes indices that companies are able to report. Though, for a long term work with sustainability a functional system and internal tool is necessary. Balanced Scorecard, BSC, is a useful tool and efforts have been made to integrate BSC and CSR with purpose to establish the work with sustainability in a more concrete and clear way.

Hur gymnasieelever resonerar kring rökning och prevention av rökning : fokusgruppintervjuer med rökare och ickerökare

The aim of the present study was to investigate high school students? ways of discussing smoking and prevention of smoking. A total of eight high school students participated in the study. Two focus groups were used to collect data, one of smokers and one of nonsmokers. Data were analyzed with inductive content analysis.

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