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498 Uppsatser om Load cycles - Sida 1 av 34
Spänningsstyrd underfrekvenslastfrånkoppling i elektriska kraftsystem
This report is a Master?s Thesis performed by Andreas Adolfsson and David Jacobsson atChalmers University of Technology. The purpose of this master?s thesis is to evaluate anew method for load-shedding, the voltage controlled underfrequency load-sheddingdeveloped by ABB. This report presents a comparison between conventionalunderfrequency load-shedding and this new method for load-shedding.
Persontäthet vid utrymningsberäkningar : Köpcentrums persontätheter
The aim of this study is to evaluate whether the value of occupant load is over or under estimated when the Swedish general value for department stores, 0,5 person/m2, is used for dimensioning shopping centers. The data that was analyzed derives from seven shopping centers and one department store. A conservative method was used to calculate the occupant load factor. The analysis shows that two groups can be discerned: one group that is characterized by a lower occupant load factor that does not exceed 0,3 person/m2, and one group with a higher occupant load factor. Shopping centers with a higher occupant load factor are located centrally in large urban areas.
Kronunionens återkomst : En empirisk underso?kning av konjunkturscykler, arbetskraftsro?rlighet och handelsintegration fo?r att avgo?ra mo?jligheten att info?ra en gemensam valuta i Norden
This paper is an assessment of whether the Nordic countries constitute an optimum currency area (OCA) or not. Hodrick Prescott-?filtered data of real Gross Domestic Product (GDP) and rate of employment are used to investigate the similarity of business cycles between the target countries through a series of correlation analysis with Sweden as the base reference country and also by using a linear regression model. Additionally there is an evaluation of trade volume and labour mobility between the countries. Our results indicate that Iceland had the least similar business cycles within the Nordic countries and that the area should therefore possibly comprise Denmark, Finland, Norway and Sweden. .
Re-Load lastpall : En jämförelse mellan Re-Load och alternativ lastpall
Syftet med denna undersökning har varit att underlätta för företaget Re-Load att presentera sin lastpall som produkt för potentiella kunder. Syftet har också varit att stötta Re-Load till att bli licenserad EUR-pall samt att successivt ersätta befintliga lastpallar och långsiktigt exekvera företagets affärsplan. Målet har varit att undersöka produkten avseende lönsamhet, miljöinverkan och hur den påverkade arbetsmiljön. Under-sökningen har genomförts med ett befintligt flöde där produkten använts och utifrån detta kunde en flödesstudie samt en komparativ produktstudie utföras med en alternativ lastpall. Med data hämtat ur detta flöde utfördes en investeringskalkylering, miljöberäkningar, subjektiva intervjuer samt dokumentation.
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.
Styrsystem : För en forskningsutrustning
The division of Engineering Materials at Linköping University, department of Management and Engineering, conducted a research project concerning Fatigue life of thermal barrier coatings during 2009. During this project equipment to provoke these fatigue failure by rapidly heating and cooling test subjects in cycles, was ordered.Design and manufacturing of the equipment was handled internally at LIU.The equipment was built using a furnace that is lowered and raised over the table where the test subject is placed. To keep the temperature of the furnace a lid slides in place to close the downward facing opening of the furnace when it is in the raised position. On this door there is nozzle that is used to cooling of the test subject by air.To make sure that the equipment can work independently you need an automation controller that can evaluate if movement can occur without danger of collisions. The control system also needs to monitor that all elements are performed according to plan.This degree project is based on a modular system from OPTO 22 and includes the configuration of a PLC that will be supplied with logic and a user interface.The degree project resulted in a graphic interface in which a user can set desired values for different parameters and get information about current values for them.
Utveckling av lastmodell för Uppsala fjärrvärmenät
The aim of this study was to develop a load prognosis model for Uppsala district heating system to be used as a tool for heat production optimization. The methodwas to build three models for the different customer types; housing, industry andoffices and then scale them for the total system using data from Uppsala districtheating system. The heat load consists of two parts, one that is temperaturedependent and one that is dependent of the social behavior of the customers. Thetemperature part was modelled with an ARX model using an outdoor temperatureprognosis as input signal. The social behavior part was modelled using the mean ofthe social behavior from some days before and additionally by distinguishing betweenweekdays and weekends.
Cash-to-cash-styrning : ett spelteoretiskt angreppssätt
Objective: The objective is to examine if long terms of payment are created because of a perceived zero-sum game in the cash-to-cash cycles between companies. The study will also examine if dependence effects the dependent companies Cash-to-Cash-cycle because of long terms of payment. Scientific method: The study uses a qualitative and a quantitative method, where primary data is collected from semi-structured interviews. Additional primary data is collected from an unstructured interview with an expert in the field of which is examined. Additional data has been collected from the studied companies? annual reports.Theoretical references: The primary theory has been Game theory, where the researchers have used this theory to analyze the behaviors of the companies.
Dynamisk modellering av kärnreaktor
The purpose of this thesis has been to develop a tool for modelling and simulating the nuclear plant Ringhals 3. The model should be used to improve the knowledge on the dynamics of the plant. Ringhals 3 is being upgraded to produce more power and a tool for analyzing the new operating conditions is needed.The work in this thesis has consisted of improving and developing an existing model of Ringhals 3 made with the modelling tool Dymola. The model has been validated by comparing the results of a simulated house load transient with data from the actual plant. Validation shows good agreement with data from the real plant.
Kvalitetsarbete i samband med byggande av betongkonstruktioner
The purpose of this thesis has been to develop a tool for modelling and simulating the nuclear plant Ringhals 3. The model should be used to improve the knowledge on the dynamics of the plant. Ringhals 3 is being upgraded to produce more power and a tool for analyzing the new operating conditions is needed.The work in this thesis has consisted of improving and developing an existing model of Ringhals 3 made with the modelling tool Dymola. The model has been validated by comparing the results of a simulated house load transient with data from the actual plant. Validation shows good agreement with data from the real plant.
Momentfördelning i pelardäck av armerad betong
The purpose of this thesis has been to develop a tool for modelling and simulating the nuclear plant Ringhals 3. The model should be used to improve the knowledge on the dynamics of the plant. Ringhals 3 is being upgraded to produce more power and a tool for analyzing the new operating conditions is needed.The work in this thesis has consisted of improving and developing an existing model of Ringhals 3 made with the modelling tool Dymola. The model has been validated by comparing the results of a simulated house load transient with data from the actual plant. Validation shows good agreement with data from the real plant.
Islastens inverkan på brottsannolikheten för glidning och stjälpning av betongdammar
There are many old dams in Sweden and, since few dams are constructed today, the main task in risk assessment on the existing dams is often to reduce the risk of failure. RIDAS (Swedish Guidelines on Dam Safety) is used when designing new dams and assess the existing ones. The guidelines include stability requirements for different failure modes, e.g. overturning and sliding, which imply that the load effect from e.g. uplift and ice load need to be less than the resisting loads or moments.
En bakgrund till skadorna på Slussens bärande konstruktioner
The purpose of this thesis has been to develop a tool for modelling and simulating the nuclear plant Ringhals 3. The model should be used to improve the knowledge on the dynamics of the plant. Ringhals 3 is being upgraded to produce more power and a tool for analyzing the new operating conditions is needed.The work in this thesis has consisted of improving and developing an existing model of Ringhals 3 made with the modelling tool Dymola. The model has been validated by comparing the results of a simulated house load transient with data from the actual plant. Validation shows good agreement with data from the real plant.
Diskret ickelinjär analys av geometriskt föränderliga linsystem
The purpose of this thesis has been to develop a tool for modelling and simulating the nuclear plant Ringhals 3. The model should be used to improve the knowledge on the dynamics of the plant. Ringhals 3 is being upgraded to produce more power and a tool for analyzing the new operating conditions is needed.The work in this thesis has consisted of improving and developing an existing model of Ringhals 3 made with the modelling tool Dymola. The model has been validated by comparing the results of a simulated house load transient with data from the actual plant. Validation shows good agreement with data from the real plant.
Energikartläggning i Sundbybergs stad
The purpose of this thesis has been to develop a tool for modelling and simulating the nuclear plant Ringhals 3. The model should be used to improve the knowledge on the dynamics of the plant. Ringhals 3 is being upgraded to produce more power and a tool for analyzing the new operating conditions is needed.The work in this thesis has consisted of improving and developing an existing model of Ringhals 3 made with the modelling tool Dymola. The model has been validated by comparing the results of a simulated house load transient with data from the actual plant. Validation shows good agreement with data from the real plant.