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2182 Uppsatser om Hydropower reservoirs; dam safety; erosion protection; waves; simulation; MIKE 21 Spectral Wave - Sida 4 av 146
Motiv till fusioner : en jämförelse mellan branscher utifrån tre perspektiv
During the twentieth century, mergers&aquisitions have occured in waves where times of low activityfrequently has turned into periods of high activity. M&A:s have been of increasing numbers and growing size, which was extra evident during the last wave during the 1990:s. What are the motives that has made M&A such a widely used strategy? Are there similarities within and across industries regarding merger motives? The empirical material consists of primary and secundary data collected from two mergers in three industries respectively; manufacturing, banking and IT. The analysis make use of three different perspectives, the reason for this being to create understanding and furthermore illuminate the complexity of the problem.
Framtagning av reläskyddsinställningar för en transformatorstation
A substation must be properly protected against lightning and other external effects to the equipment in the station or staff, for that we use relay protection. They should also protect against internal errors which may occur as ground faults. There are different types of protection relays, but most common are overcurrent-, distance-, residual current- and differential protection.The purpose of this thesis was to deepen our knowledge of relay protection and to use the theoretical knowledge we got from the university studies in the work process. In the process we discovered which parameters were the most essential and calculated these for all relay protections on the substation. We also carry out a comparison between two brands of relay protection, ABB and Alstom.During our work we will test and simulate the over-current relays in a program called NEPLAN, the program will also calculate the fault currents.
KONSTRUKTION AV AUTOMATISERAD SKYDDSANORDNING FÖR ABB / JOKAB SAFTEYS STAKETSYSTEM
This thesis is basically a design project aimed to find a safe and reliable automatic safety device, which is designed to be suitable for highly automated industrial situations. This device fits with ABB / Jokab Safety?s fence systems. These are built up around machines to create safety distances. The automatic protection device assist the operator in situations when loading or going in and out of the danger zone.
Environment simulation of track-based systems
Simulation means running a model of a system with suitable input and observing the corresponding output. Real-time environment simulation is a special kind of simulation used to simulate a control system's environment in real-time. This is done to test the control system before it is used in its real environment. In this project, computer simulation of a certain kind of environments, called track-based systems, is studied and a general model for track-based systems is developed. In this model, track layouts are represented by graphs, which is a flexible and extensible representation and a method for visualizing these layouts is presented.
Simhall i Viskafors
Today, the catering personnel are an essential part of the safety organization on board Swedish passenger vessels in ferry services. Their responsibilities for the safety on board have increased in connection with the changes in regulations made on the shipping industry. These changes have been mostly related to human factors and structural leadership in the last 25 years.A well-functioning safety organization requires competence and commitment from every individual. Previous researches on Swedish passenger ferries concerning the safety organization have raised issues regarding the catering personnel?s perception of the safety on board.
Upprepade ljusstimuli orsakar interferens i mörkeradapterade elektroretinogram hos hund : en utvärdering av några av European College of Veterinary Ophthalmology´s rekommendationer för elektroretinografi på hund
Electroretinography is an examination method where the function of the retina is objectively assessed. In 2002 the European College of Veterinary Ophthalmology (ECVO) published a proposition to a standard on how to perform ERG examinations, to facilitate comparison of results and to make it possible to repeat examinations.
The purpose of this study was to validate parts of the canine ERG protocol suggested by the ECVO. Our principal aim was to study if there is any interference at the recommended stimulus intervals for dark-adapted rod- and combined rod-/cone responses.
The results show that there is an effect on the a- and b-wave amplitudes when different stimulus intervals are employed. When all examined intervals are pooled, there is an increase in the median b-wave to each consecutive dim, white (rod) stimulus in a series of four.
Konstruktion och utformning av skydd till spolverk
This thesis has been carried out in cooperation with Burseryds Bruk AB.Burseryds Bruk is a company that manufactures steel strapping. The thesis isabout developing a concept of protection that should be used to protect theoperators from the rotating parts of the machinery lines. The aim of the projectwas to improve work safety for operators working at the machines by producing aconcept for a protective device. The project's first part was based on ergonomic data collection methods tounderstand the operations performed on the machine and the hazard occurringduring the process. The methods used to collect data were, interviews,observations and questionnaires with the operators of the company. This was thenused to make the ergonomic analyzes hierarchical task analysis and link analysis. The data collected from the company's operators was used create 10 conceptswhich were then evaluated.
Ytterväggar och bjälklag för flerbostadshus
The thesis demonstrates protection solutions that can be suitable for a camp during internationalmissions in order to resist complex threats. The threats could consist of small arms, machineguns,RPG 7, anti armour missiles, mortar, artillery, HPM-weapons, car bombs, biological and chemicalweapons as well as sabotage and theft. It?s not the technology itself that makes the threat scenariocomplex it?s the way the opponent acts during the operations. The opponent acts usually incivilian clothes and therefore he is difficult to distinguish from other civilians.
Cykelolyckor i korsningar : Hur kan trafiksäkerheten förbättras?
Stockholm city has recently raised its ambitions for bicycle traffic, the goal is to achieve a larger andsafer bicycle traffic. But cyclists are more vulnerable on the roads than other vehicle users because of the lack of protection. This means that a large proportion of road safety for cyclists is based on the design of the traffic environment. Since most serious bicycle accidents are those that occur in conflict with motor vehicles, and the majority of these accidents occur at intersections, these areas are of great importance forcyclist?s safety.The purpose of this paper is to highlight bicycle accidents at intersections and to suggest improvements in three accident-prone junctions in Stockholm. This is achieved by the study of accident statistics, literature and finally three case studies.The literature study focused on cyclists, traffic safety and traffic safety measures.
Avbördningskapacitet för Traryd kraftverk: en modellstudie vid dimensionerande flöde
Sydkraft Vattenkraft AB owns and operates the Traryd hydropower plant, located in the river Lagan in the southern part of Sweden. The gravity dam is classed according to RIDAS guidelines (Hydropower Industry Dam Safety Guidelines) as a class 1B dam. This means that the dam must discharge a class 1-flow which has a return period of 10 000 years. The inflow into the dam has been calculated in an earlier report to 495 m3/s, with a waterline at an elevation of 126, 3 meters above sea level. The gravity dam has a discharge system with two rectangular weirs, which results in a smaller discharge than the necessary 495 m3/s.
Modellering av reserv- och nödkraftsystem i JAS 39 Gripen
Simulation is a vital tool during development of JAS 39 Gripen, since money and time can be saved.The Auxiliary and Emergency Power System, AEPS, is a subsystem of the secondary power system in Gripen. It has the function of providing the aircraft with electrical and hydraulical power before activation and after deactivation of the main engine. The system also functions as backup in case of a safety critical problem in the main power supply system. The system basically consists of a control unit and an auxiliary gearbox. The gearbox is driven by an air turbine.
Cito Systems ? Mjukvara i form av ett stödsystem för restaurangbranschen
Stockholm city has recently raised its ambitions for bicycle traffic, the goal is to achieve a larger andsafer bicycle traffic. But cyclists are more vulnerable on the roads than other vehicle users because of the lack of protection. This means that a large proportion of road safety for cyclists is based on the design of the traffic environment. Since most serious bicycle accidents are those that occur in conflict with motor vehicles, and the majority of these accidents occur at intersections, these areas are of great importance forcyclist?s safety.The purpose of this paper is to highlight bicycle accidents at intersections and to suggest improvements in three accident-prone junctions in Stockholm. This is achieved by the study of accident statistics, literature and finally three case studies.The literature study focused on cyclists, traffic safety and traffic safety measures.
Översvämningsmodellering av ett dagvattensystem
Storm water management has become a more important matter as urban areas are expanding and natural areas are being exploited. As nature landscapes are being converted into hard surface areas storm water flow is affected both in terms of velocity and size. A flow increase can easily result in a flooding if the dimensions of the pipeline system are inadequate. Considering predicted upcoming climate changes, flooding?s may become more common in urban areas in the future.
Stranderosion i Skåne
Erosion är en ständigt pågående process som formar om vårt landskap. Längs med kusten pågår ett samspel mellan vind, vågor, strömmar och sediment. Ett område kan sägas vara utsatt för erosion om mängden borttransporterat material är större än den mängd som avsätts. Det omvända kan också inträffa, det vill säga att stränder växer. Detta kallas för ackumulation.
Förutsättningar att utforma stationsbatterier i vattenkraftverk med Li-jonteknik
In hydropower plants it is necessary to always have local power supply. Therefore, the plants are equipped with batteries as stationary back up power. Vattenfall Vattenkraft is using lead acid batteries but has been investigating alternatives to replace them. The aim of this study is to investigate the potential of using Li-ion technology as back up power.The study showed that Li-ion batteries have many qualities. The Li-ion technology will decrease the space and maintenance demand.