Sök:

Sökresultat:

11955 Uppsatser om Viable System Model - Sida 11 av 797

Förstudie för kvalitetssäkringav glidande förband vid Hissmoforsvattenkraftsstation : -Specifikt för aggregat G6 och G7

Jämtkraft AB which is a power production company in Sweden has bought two newhydro power units to their station in Hissmofors. The two new generators are using aconcept with sliding stator feet to handle the thermal expansion.The concept with sliding stator feet on hydro electric generators has not beenworking satisfactory on many hydro power stations in Sweden and has caused a lot ofcosts due to long downtimes.The new station in Hissmofors is very important for Jämtkraft AB, and therefore theywant to know how to make sure that the sliding stator feet are working as theyshould. According to theories and a simplified model of the generator the stator feetdisplacement should be around 1 -1,6 mm.The generators are delivered with a surveillance system that will measure thedisplacement of the sliding stator feet. The signal from the system isn?t accessible forJämtkraft AB but it will alarm when the sliding stator feet are malfunctioning.To secure the function of the sliding feet a logger for the surveillance system or adifferent measurement system must be used; if both systems are used Jämtkraft cansecure the function of the surveillance system..

A Strategic Decision-Making Model for Supply Chain - A Void to be Filled

Many researchers emphasize the increasing strategic importance of supply chain management, but there is still a lack of concrete guidance for managers faced with strategic decisions in supply chain. Within decision-making theories, the rational decision-making model is the most commonly used. This because of its suitable foundation, enabling a structure to the complex decision process. The rational decision-making model is today not developed to include the aspects of strategic decision-making made in supply chain. The purpose of this research is to adjust a structured rational decision-making model, making it applicable for strategic decision-making in supply chain.

Lokal anpassning och implementering av Operation Management System

In this thesis, a transparent model of the human head has been constructed which was filled with a substance that represented the brain. This model was later crash tested. This was done in order to examine how a transparent model of the human head can be constructed to generate accurate data from crash tests. It was also done in order to examine how impacts on the front of the head can deform the rear of the brain. When a head is decelerating, the brain moves forward inside the skull and may hit the front of the skull.

Ny princip för spänningsreglering i Fortum Distributions mellanspänningsnät i Stockholm.

The voltage regulation in Fortum Distributions medium voltage network in Stockholm does not work satisfactory. This results in too high distribution voltages with many customer complaints as a consequence. The reason is the model responsible for compensating for voltage drops in the distribution network. Despite several adjustments Fortum has not been able to find the source of the high voltages and has therefore appointed an investigation in the form of a thesis work.The aim of this investigation is to locate the error and to produce a proposal regarding the solution of this error using the existing system, common industrial knowledge, state of the art research and the option to use voltage readings from the different substations.The conclusion of this master thesis is that the largest contribution to the high voltage levels is made by the large compensation for distribution loses. Furthermore an additional error in the model has been found.

Valutamarknadens effektivitet - En studie av växelkurser utifrån UIP med förväntningar

This essay discusses and evaluates the international currency market in regards to efficiency. To prove the theory that, the difference between expected and actual exchange rates is explained by the difference in expected and actual interest rates and the difference in expected and actual inflation between countries, a model was developed. This model was inspired by the paper of Sebastian Edwards (1982), and is based on three theories; UIP, IS/LM and the Efficient Markets Hypothesis. The model uses 16 regressions estimated from three pairs of curriencies: $/SEK, £/SEK and ?/SEK.

Empirisk studie av den radiella förspänningskraftens variation i klassiska skärskruvförband

In this study, the pre-tension force in an insert screw connection are examined in order to establish a greater understanding of the system and to facilitate the process of making new metal cutting tools. Certain especially significant design variables such as the offset, the length of the contact thread and the shank length above the threaded hole, are selected to be closely examined. A comparison of the influence on the pre-tension force between threaded holes made with a worn, versus new, threading tool is also involved in the experiment. The study is limited to handling the screw sizes M2,5 and M3,5. The results show that a regression model, with good approximation, can be fitted to the measured values.

Att veta Gudarnas hemlighet : En sårbarhetsanalys av omständigheterna kring stormen Gudrun med pressure and release modellen

The concept of vulnerability is the capacity or the sensitivity to become damaged. Vulnerability are characterized by one or more of the following terms; a system´s sensitivity to exposure to shock, stress or interference, the state of the system in relations to a threshold of damages, and the system´s ability to adapt to the changing circumstances. Vulnerability in this study is referring to the sensitivity of the circumstances that lead to sustainable livelihood that can´t be maintain and that there is an inability to cope with and manage stress. The choice of making a study in this area is based on that action needs to be taken to moderate the vulnerable aspects of society, in this respect in relations to storms. Analyzes of the social vulnerability to climate change or natural events is needed for effective actions.

Kan konsumentförtroende användas för att prognostisera konsumtion i Sverige?

Making accurate predictions of private consumption expenditures is a difficult task. This thesis examines if consumer confidence can be used to forecast consumption. Using regression analysis, the link between consumer confidence and private consumption expenditures is analyzed for Sweden between the years 1994 and 2005. Two different models are estimated. In the first model consumption is regressed only on consumer confidence, while model two is extended to contain more variables.

3D-modellering i AutoCAD -att skapa en digital huskonstruktion

3D-modelling in AutoCAD This thesis is done in cooperation with LB-Hus in Bromölla, and have aimed to establish a digital AutoCAD model of one of the company?s house types and to find out what opportunities there are to do visualisations in the form of images directly from the programme. Modeling has been carried out so that the very construction of the house is included. Interiors and installations, with the exception of the ventilation system, have been left out in the model. The model has been created with solid models after a comparative study made between solid models and surface models to find out which option in this case was the easiest to handle and took up the least space.

Automatisk mätning och detektering av röjande signaler

This master thesis has been performed at Sectra Communications AB in Linköping where they manufacture electronic encryption devices. In cryptology it is essential that an eavesdropper cannot find the plain text. To assure that a system is safe, all devices are thoroughly examined so that they don?t emit any secret information, so called Compromising Emanations (CE). This is done by comparing the secret signal with measured signals on the screen of an oscilloscope, a process that is very time consuming and furthermore, the risk of missing compromising emanations is high.

Från digitalt utanförskap till digital gemenskap : En hypotetisk väg till digital gemenskap

We are in an emerging digital society where we are increasingly dependent on the mastery of IT and digital technologies to better carry out our everyday tasks. They cover everything from keeping in touch with family and friends to pay bills and declare. At the same time there are those who have not learned how to use the new technology and live their lives outside of the digital society. What happens to these people, in a society that is becoming increasingly digitized? Do they take harm by being in digital exclusion? It looks like this are issues that will not become less important as digital technology constantly changes.

Radioräckviddsberäkningar för flygande plattformar

There exist several known methods for calculation of radio coverage for ground-based systems. As far as we know there are no equivalent methods for the case of flying platforms when the altitudes and speeds are significantly different to those of ground-based systems. This thesis describes the theoretical concepts behind calculations of radio coverage for flying platforms. An investigation is made to sort out what is important and possible to employ in a model for simulations. A method is described and implemented in a program for evaluation of flying radio systems.

Energieffektivisering och solenergi i en universitetsbyggnad : Undervisningshuset och Biblioteket i Uppsala

Akademiska hus is a real estate company that specializes in providing Swedish universities with housing facilities for educational and research purposes. The company strives to reduce its use of energy by 40% between the years 2000 and 2025. The aim of this thesis is to determine which measures can be taken to reduce the need of purchased energy in a building that is used by theSwedishUniversityof Agricultural Sciences inUppsala.In order to determine the results of various changes to the building envelope and ventilation system, the building was modelled in the computer simulation program VIP-Energy. Other proposed changes to make the use of energy more efficient concerned water use and lighting. The need of purchased energy can also be reduced by producing electricity or heat on site, using solar energy.Results show that economically viable measures include upgrading windows and faucets, adjusting control systems for ventilation and lighting, and installing roof mounted solar panels for power production.

Yrkesrelevant Gymnasiearbete på El- och Energiprogrammet

The purpose of this development project is to create a model for working with a high school project in Electrical and Energy Program. It should be conducted in a form like companies do according to the goals from The Swedish National Agency for Education. In order to fully perform this we use the concept of Young Entrepreneurship. The model is created according to the new conditions from The National Electrical Safety Board. There is now an exception saying that a student during education is released from the demand of employment that is the normal procedure where you are under supervision from a certified electrician. During the project there has been theoretical and practical examinations in order to clear out the advantages and disadvantages using this model, but also to examine whether it is useful in the future and to what extent it can be used. The result indicates that the model is useful and fulfills the goals from The Swedish National Agency for Education but that the model has its limitations and difficulties.

Termisk Vattenpump

 This degree project aims at developing a concept for how to use solar energy to pump up water. The target audience is people living in areas where the functioning of the electricity and water network is absent. In these areas, the hand-powered water pump is the most common technology. The degree project's goal is to find an economically viable alternative to the time consuming hand-powered water pumps. The power comes from solar energy.

<- Föregående sida 11 Nästa sida ->