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8976 Uppsatser om Ventilation system - Sida 11 av 599

Hjälpkraftsystem med två lågspänningsnivåer

Because of increasing demand of power on Malmbanan the capacity of the existing wires which supply the trains must be increased. This increases the stress on the existing poles and for this reason the system for supplying the loads along the railway is to be removed from the poles and be replaced by some other system. This thesis is a study on a two-level low voltage (1 kV and 0.4 kV) electrical system with the aim to investigate if it can be an alternative to the system used today taking into account the voltages, fault currents and costs.In this thesis the following tasks have been performed:? Gathering of data? Description of basic theory? Loadow and fault current calculations of the system with MATLAB? Life Cycle Cost estimate of the system? Analysis and conclusions from the resultsThe results show that the new system can be an alternative to replace today's system. The simulations and calculations show that the voltage drop is at an acceptable level and that the fault currents are large enough to supply a safe disconnection if a fault occurs at the far end of the system..

Business intelligence : Framgångsfaktorer vid användningen av ett BI system

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.

Upphängningssystem

Examensarbetet som utförts på Institutionen för Maskinteknik vid Blekinge Tekniska Högskola i samarbete med Kockums AB har benämningen ? Upphängningssystem?. Dagens upphängning av rör, ventilationsrör och kabelbanor består av ett antal olika singelupphängningar utan större samordning. Detta har gjort att Kockums AB önskat få fram ett samordnat upphängningssystem som klarar av alla dessa upphängningstyper. Utifrån denna problemställning har vi arbetat oss fram till ett upphängningssystem bestående av ett multisystem och ett flertal singelupphängningar för rör, kabelbanor och ventilation.

Åtgärdsförslag och känslighetsanalys vid energieffektivisering ur ett fuktsäkert perspektiv : En fallstudie på timmerhuset Sofiedals herrgård

This thesis investigated the possibilities to resume cultivation of an old manor house built of timber and what this would mean from an energy and moisture perspective. The building in this case study is named Sofiedals mansion and was built in 1858 in Valbo 11 kilometers west of Gävle.The structure of the house was documented and used as a starting-point for carrying out calculations focused on energy and moisture aspects. With the help of a number of computer programs and a conducted air tightness test, the buildings energy consumption were calculated and compared with the current building regulations.In addition, the building was analyzed considering energy retrofitting and what it meant for moisture problems. The energy retrofitting consisted of additional insulation, decreasing the buildings permeability through air sealing; window and door replacements. When a building is equipped with natural ventilation it is difficult to know its precise performance and how an energy retrofitting affects it.

INOMHUSMILJÖ I SMÅHUSMED FTX-VENTILATION : EN LITTERATURSTUDIE MED ENKÄTUNDERSÖKNINGAR OCHMÄTNINGAR

This master thesis was initiated with the aim to answer at what level of installed capacity of wind power in the northern parts of Sweden it would be beneficial to improve the transmission capacity from the northern Sweden. During the process of this work the aim has changed to try and create a model that can be used to analyze how well the hydro power installed in the northern Sweden can even out the quick changes in wind power production.To create a good model of all hydro power in northern Sweden is a very large job, unfortunately too large for a master thesis. This report therefore ends with an extensive analysis of the simplifications that have been made and their effects as well as a list of the future work that has to be done.The model that has been created have shown to be effective and produce good results. The conclusions that can be made is that the northern Swedish hydro power have very good possibilities to balance the wind power production. Only a few cases where water have been spilled even though there has been some free capacity has been discovered.

Dags att förändra den svenska utnämningspolitiken! En idéanalys

This paper discuss the possibilities to improve the Swedish political nomination system. It brings up some of the values and norms that can be used to change the existing system. Values as openness, the demand of responsibility and also if there is values from the American spoils system that can be used in the Swedish system. A minor purpose is to discuss the part of the parliament within the nomination process. To investigate this I have some theoretical starting points and a self constructed analysis tool.

Förändring = Förbättring? : En studie av hur några användare skattar och upplever förändringar i ett datorstöd

Human-computer interaction is central for computer assisted development. The aim was to investigate the user experience of a new (U2) compared to an old (U1) computer system, within a cognitive psychology frame of reference. Six subjects, frequently using the system, participated in the study. It was shown that the new (U2) compared to the old system (U1) enhanced and supported more the users? system related procedures/tasks.

Energikartläggning av polishuset i Gävle : Åtgärdsförslag för ett minskat energibehov i fastigheten Gävle Söder 17:10

The objective of this work was to introduce measures to reduce energy and water demand at Gävle Söder 17:10. To succeed, this energy audit has been made. The work is based on collected statistics from the property owner Norrporten, measurements, literature review and through consultation with experts in the field. Two models, one for each building, have been created in the simulation program BV2 to estimate the potential of energy measures based on the collected information. The models in BV2 have been verified against the statistics of the energy consumption.With the help of calculations and simulations, seven cost-effective measures have been identified.

En studie av fysiska, organisatoriska och individuella riskfaktorer hos arbetstagare med datorarbete

Musculoskeletal disorders (MSD) are common in individuals with computer based work. Thecurrently known risk factors for these disorders is in the literature derived to physical,organizational and individual factors. A recent survey of three working groups at a companyin Stockholm explored that more than 50% of the employees had neck and shoulder problems.Aim: The study aims to create a better understanding for the current musculoskeletalproblems at the company. Such an understanding is created by examining the physical,organizational and individual risk factors in the workplace and the result can provide a goodbasis for intervention proposals.Method: In order to answer the aim of the study the authors chosed to use both qualitativeand quantitative methods of data collection through interviews and questionnaire survey. Theinterview and questionnaire was designed to create both a specific and comprehensive pictureof the physical, organizational and individual risk factors having a bearing effect on theexisting MSD problem.Result: Seven categories were compiled from interviews, which largely deals with the factthat high demands can lead to behaviors that may pose a significant risk for the occurrence ofMSD.

Ett mät- och reglersystem för temperaturkompensering

An automatic control system for calibration of pressure indicators has been constructed. This control system can be used as a complement to the calibration system located at AerotechTelub, division MainPartner, in Linköping. The calibration system used today contains some not wanted pressure changes, which is compensated by hand today. The new system presented in this report automates the calibrating process and simplifies the calibration. Suitable hardware as motor, controls card and so on have been found and software in the form of Visual Basic program has been developed.

Effektivare produktionsarbete med BIM som arbetssätt på Skanska Väg och Anläggning region Stockholm

The author of this report has created a Web-based invoice system and CRM at therequest of the company Webhouse.se. The purpose of the System is to makeeveryday tasks in the company easier. The system also needed to prevent mistakesand errors by managing orders and invoices.The system has been created with the company?s requests in focus. During thedevelopment of the system information security and interaction design have beenimportant aspects that have been taken into consideration.The system has been created using techniques such as PHP and MYSQL.

Resurssnålt kommunikationsprotokoll för små inbyggda system

Web Services har vuxit i popularitet de senast åren. Användningen av inbyggda systemökar också ständigt, och möjligheten att göra inbyggda system tillgängliga via Web Services öppnar nya möjligheter.Detta arbete visar på möjligheter och problem med standardiserade textbaserade protokoll för kommunikation i inbyggda system med små resurser. XML-RPC och SOAP studeras ur detta perspektiv. SOAP befinns vara mer komplext att implementera stöd för än XMLRPC i den begränsade testmiljön, som har 32kB internminne. XML-RPC visar sig ge fördelar över proprietära protokoll främst när det gäller underhållbarhet och återanvändbarhet..

Metoder för lastprioritering i fjärrvärmecentraler

A problem in the field of district heating is the oil burners needed to provide power when a peak load occurs. One possible way of reducing the needed amount of oil is to reduce the power demand for space heating in the district-heating substations when the need for district heating water exceeds a certain limit. This can be done by use of a locally working controller function.In this Thesis the options concerning load priority are evaluated. To evaluate the potential for using controller functions concerning peak load priority an experiment was brought out in a chosen district-heating substation. The impact on the indoor thermal comfort during a heat reduction was also taken into account.

Driftsäkerhet i verksamhetskritiska system

Vi har undersökt ett verksamhetskritiskt system i en större organisation för att se hur systemet är konstruerat och hur förvaltningsarbetet bedrivs för att undvika avbrott i systemet. Då det är särskilt viktigt att dessa system har hög tillgänglighet har vi försökt lyfta fram faktorer som visat sig vara särskilt viktiga för att uppnå hög tillgänglighet. Undersökningen har genomförts som en fallstudie där vi intervjuat personer med olika befattningar inom organisationen. Vi presenterar även ett antal rekommendationer som vi tror kan minska risken för avbrott i det undersökta systemet..

Feedforwardreglering av ventilation på Kiruna flygplats

Denna rapport utreder huruvida feedforwardreglering av ventilationssystemet på Kiruna flygplats leder till lägre energianvändning. Rapporten jämför ett feedforwardreglerat system simulerat i Simulink med ett feedbacksystem som motsvarar det existerande systemet på Kiruna flygplats. Jämförelsen görs på fläktens energianvändning och rapporten använder sedan energianvändning för värme och kyla för att avgöra huruvida systemet är ekonomiskt gångbart. Systemet är tänkt att kunna användas i alla miljöer med kända störningar i avseende till tid och storlek som till exempel flygplatser, biosalonger, teatrar och så vidare.Rapporten ger en kort teoretisk bakgrund till hur ventilationskrav, reglerteknik, feedforwardreglering och feedbackreglering fungerar för att sedan gå vidare till att redogöra för de förutsättningar som gäller för Kiruna flygplats med avseende på klimatskalets täthet, rummens volymer och utformning och drifttiden för ventilationssystemet. Med hjälp av simuleringar i Simulink görs en jämförelse av energianvändning då de båda systemen är optimerade utan att för den sakens skull kompromissa med kvalitén på inomhusmiljön.

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