IT - systemen har blivit en del i samhället. IT -system används inom olika områden och verksamheter i och med detta så har användbarhets faktorer i IT -system blivit sådan som inte går att bortse ifrån. Det finns många användbarhetsfaktorer som alla skiljer sig mer eller mindre åt. Gemensamt för dem alla är att ett system bör innehålla visa kriterier för användbarhet för att godkännas av användaren då de använder sig av ett IT -system.Det finns en vilja att skapa användbara system för att underlätta för användaren. Visa faktorer i användbarhet i ett IT -system är genom tänkta medan andra behöver förbättras för att anpassa till beslutfattande och ta hänsyn arbetsmiljöaspekter.

Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.

Värnamo Elnät owns and operates a ripple control system which is used to control loadsespecially when the grid is heavily loaded and for control of street lighting. This report aims atclarifying technical and economic aspects of the ripple control system?s future. The system wasinstalled from 1975 and onwards and its use was greater in those days when the controllableloads where greater then today, the current controllable load level is about 3 MW. The reporthighlights three different aspects of the ripple control system?s future ? retain the currentsystem, reinvest in a newer system or discontinue the system.In the report the author also discusses relevant connections to Smart Grids and future meteringsystems and tariffs.

In this essay I analyze the performative aspects relating to Marina Abramovi?'s The Artist Is Present, which took place in spring 2010 at MoMA in New York, from the context of the artist and work, institution and documentation. In this performance work, for the duration of the exhibition, Abramovi? sits completely still opposite another chair where anyone from the audience may sit. The art arises through this participation.

Today?s electrical grid companies understand that better knowledge of and information about their grid can help realize a smart grid network. One way to gain better knowledge and information about the low voltage network is to install measuring equipment on the substation transformer´s secondary low voltage side that measures the low voltage network losses for that specific substation. By doing so, grid companies can, due to the calculation of the low voltage network losses, identify and address issues such as illegal power dissipation, unmeasured power outtakes, and unsatisfied technical documentation for the substations low voltage network.During 2012, Mälarenergi Elnät AB had a total electrical network loss (both medium and low voltage network losses included) of three to four percent of their total distributed electrical volume. Converting this energy volume into a monetary figure this accounts for a loss of around 30 million Swedish crowns.

The management of information is a significant competitiveness in companies. Companies stored and save information every day, and it is very common to save de information in different sources. This makes de management of information complex. To mange, monitor and analyze the information, companies can use a system called Business Intelligence. BI system is an analytical system that extracts and converts data into useful information that helps employees to make informed decisions.

Budgeten fyller en viktig funktion i Frigoscandias planering och styrning och fungerar som en handlingsplan över hur resurser skall fördelas. Risken finns dock att budget leder till att kortsiktiga mål prioriteras på bekostnad av långsiktiga samtidigt som det är en kostsam process. Istället kan ett företag värdera sin verksamhet utifrån icke-finansiella aspekter med hjälp av ett Performance measurement system, som exempelvis BSC, för att kunna fånga den komplexitet och mångfald som råder i ett företag. Syftet med uppsatsen är därför att beskriva och analysera hur ekonomistyrningen kan förbättras med hjälp av ett BSC i ett företag, inriktat på lagringsverksamhet, vars nuvarande styrverktyg är budget. För att uppnå vårt syfte valde vi att använda oss av en kvalitativ metod, då den djupare förståelse vi sökte av vårt ämne ej skulle kunna uppnås med en kvantitativ undersökning.

Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.

The demand for environmental assessments on buildings and energy consumption is increasing as well as the energy performance requirements for buildings. At the same time it is increasingly common with self-producers of heat and electricity generation.The main purpose with this master thesis is to investigate how time resolution affects the environmental assessment of energy consumption in office buildings connected to district heating (DH). Environmental assessments were done with both attributional LCA and consequential LCA with system expansion.Fortum´s DH system in Stockholm was analyzed and district heating production was simulated in a Matlab-model. Greenhouse gas (GHG) emissions for the production were calculated. The heat demand of the office Gångaren 16 in Stockholm was simulated in IDA ICE.

This report is an examination paper in computer science at University of Växjö. The report will focus on the possibility to create adaptable systems and to cost calculate the work needed to modify a system to meet new demands. A project [demos] developed by Interactive Institute studio [12-21] in Växjö is the starting point in our work. They have during a period of two years developed a prototype of a system which intends to get youth and democratic selected representatives a communication platform where they may communicate with SMS. Today they are in a position when they want to develop the system for other user groups with slighter different purpose and to do that they need a more flexible system.

Den här rapporten har som syfte att utreda vilket eldistributionssystem för offshoreenheter som sparar mest vikt och utrymme. De två elsystem som jämförs är GVAs standard system och Siemens Blue Drive System. Rapporten innehåller en teoretisk bakgrund för båda systemen och dimensionering av systemens kraftkablar samt beräkning av kabelvikter och komponentvikten för systemen. För att uppskatta kabel- rutter och längder kommer ritningsunderlag för GVAs offshoreenhet 7500 att användas.Resultatet visar att GVAs standard system är det eldistributionssystem som har den lägsta totalvikten med 168 ton, GVAs standard system har en vikt som är 101 ton lägre än Siemens Blue Drive System som har en vikt på är 269 ton. GVAs standard system har en lägre ström vilket gör att ledararean blir mindre och i med det blir kabelvikten mindre.

Simulation of different systems can be done using a graphical model description of the system based on block diagrams. The simulation software Matlab/Simulink offers a lot of possibilities to describe a huge number of systems, which can be linear as well as nonlinear. The simulation using Matlab/Simulink is done by integration based on different kinds of numerical methods.When nonlinear Simulink-models are simulated, it is often interesting to apply a Kalman filter to handle the noise that may occur within the process as well as corrupting the measurement. However, application of such a filter leads to an extensive time-consumption despite using fast computers. The reason is that the existing Matlab functions are not constructed for time optimal evaluation.

Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.

Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.

Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.