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3983 Uppsatser om Electrical distribution systems - Sida 48 av 266

KORTSIKTIG PRODUKTIONSPLANERING I MINDRE FJÄRRVÄRMESYSTEM : En studie vid Strängnäs Energi AB

District heating covers around 80 % of the heating demand in apartment buildings and 10 % in single-family homes in Sweden. In the year 2010 the total input of energy to the Swedish district heating grids was about 70 TWh, which corresponds to 11 % of the total energy input to the whole energy system in the country. Through the combined production of heat and power the CHP-plants often reaches an efficiency of 90 % from energy in the fuel to produced heat and power. In order to keep the efficiency high it is important for the owners of the plant to have good knowledge about the plants performance at different operation points. Strängnäs Energi AB initiated this diploma work together with FVB Sverige ab in order to come up with a program for short term planning of the production of heat and power at the company´s CHP-plant.The work consists of three main parts.

Rekommendationssystem för interaktiva musiktjänster : en utredning av aktuella trender och attityder gentemot framtidens rekommendationssystem diskuterat ur forskar-, industri- & användarperspektiv

Parallel to new technological advancements, including the development of interactive recommender systems, digital music services on the Internet, such as Spotify, have in a short time span gradually replaced former physical media such as CDs and MP3-players and become pioneers on a market with an otherwise uncertain future. By subscribing to the service, users have access to a vast library of music and from any device with Internet access. In order to provide a satisfactory and useful musical experience, different ways of coping with the vastness is required - which is precisely what recommender systems are for. Improved filtering techniques and use of devices built in sensors, make way for new opportunities of more precise and contextually tailored suggestions for track selection, which in turn leads to potential privacy issues when using interactive music services. But where do we stand today? By compiling, exemplifying and discussing three different perspectives with relating to the development of interactive music recommender systems, the objective for this paper is to provide a for science, industry and user, objectively nuanced account of current potentials and expectations.

Programvaruutveckling för en elektromagnetisk skanner med fokus på användaren, användarstudier och inlärning

The project was based on a request to improve an already existing program and hardware at the electrical engineering department at the royal institute of technology. For maximum ease of use, tests have been done on students to properly design the program for what it is meant to be used for. These tests have been transcribed and analysed, then brought back to the group in a discussion and then transcribed and analysed again, I call this process the ?four step process? (this process is presented and explained in chapter 6.4.). A part of this master thesis was also to analyse the four step process to enhance validity of this research.The project resulted in a new program with a new graphical view and features to help students and researchers to work with the technical tool for electromagnetic readings of planar objects.

Premiepensionens Marknadsrisk : En Monte Carlo-simulering av den allmänna pensionen

A reforming trend is captured showing that countries are shifting from defined benefit pension systems towards defined contribution systems. The reforms have been justified through predictions that the defined benefit systems will not manage to provide good enough pensions to members in the future. The newer defined contribution pension plans often include individual financial accounts where individuals have the possibility to choose how a part of their pension savings should be invested. Sweden was early to introduce such a system, which at the moment provides more than 800 funds to choose from. The aim of this thesis is to capture the market risk associated with these individual investments and does so by using Monte Carlo simulations for six selected pension funds.

Arbetsmiljöansvar vid uthyrning av personal

As the staffing agency business is rapidly growing and suffering from accidents resulting in higher sick leave than in other businesses, it is of great interest to analyze which responsibilities prevail between the customer companies and the staffing agencies, when it comes to working environment for hired staff.The purpose of this essay is to clarify the distribution of responsibilities between customer companies and staffing agencies, regarding working environment. I would also like to analyze which consequences this distribution of responsibilities may lead to.To be able to answer these questions, I have chosen to use the legal dogmatic method together with the sociology of law method. I have studied legal sources, literature and also interviewed three persons who are active within the staffing agency business; one person from the Swedish Work Environment Authority, one person from the employers? side and one person from the employees? side.The conclusion of my survey is that the SAM-responsibility is divided equally between staffing agencies and customer companies, since the customer company who hires staff is equated with an employer. The employer must also ensure that there is an organized work adaptation and rehabilitation function within the company.

Energieffektivisering av industribelysning : Planering av belysningsanläggning i mekanisk verkstad

In Uppsala, Sweden, Vattenfall has a combined heat and power plant. On the premises there is an engineering workshop with old fluorescent and mercury lamps that need to be replaced. This provides a great opportunity to save energy and money by installing more efficient lighting. The main purpose of this study was to present two functional and energy efficient lighting systems including control system. The lighting systems were designed by investigating the working environment, measuring illuminance and by simulations in the software DIALux.

LCC-analys av FTX-system : En jämförelse av centralt- och lägenhetsplacerat

This report is the result of a thesis conducted at the consulting firm Bjerking AB andis the final part of the Bachelor Programme in Construction Engineering at Universityof Uppsala. The work aims to investigate the costs and how the choice of ventilationsystem affects building projects during a long-term period. This report covers costssuch as investment, maintenance and energy but also how they affect residents andbuilders. Building regulations for energy consumption are expected to be tougher;therefore a comparison of two different heat recovery ventilation systems(HRV-system) was made. One system is based on a centrally placed unit that coversthe whole buildings ventilation through vertical shafts.

Internetbokhandelns rekommendationssystem : en undersökning av Amazon.coms Similar Items.

The aim of this thesis is to examine one part of Amazon.coms recommender systems: Similar Items. The purpose is also to show the difficulties with subject access, i. e. to find a similar book to the one you just read; problems with traditional systems versus the usefulness with recommender systems like Amazon.coms Similar Items. Similar Items presents a set, a cluster of related items to a given item based on customers co-purchase.

Frågehantering i en mobil databasmiljö

Rapportens studie jämför en distribuerad och mobil databasmiljö med avseende på frågehantering. Områden som fokuseras inom frågehantering är: dataorganisation och distribution, lokaliseringshantering, skalbarhet, frågekostnader samt frånkopplad operation. Rapportens slutsatser fastslår att grundläggande skillnader inte existerar mellan miljöerna med avseende på frågehantering, vilket ger till följd att formulerad problemhypotes verifieras..

Driva tulpaner i näringslösning eller i jord :

The aim with this thesis is to make a comparison between forcing tulips in a hydroponic system and the forcing off tulips that have been planted in soil. The results are mostly based on interviews with six Dutch and one Swedish tulip forcer and the managing director at the Horticultural Research Centre, Proeftuin Zwaagdijke, in the Netherlands. There are benefits and disadvantages with both methods. Tulip bulbs planted in soil seem to get a brighter colour after forcing, compared with those forced ?in water?.

Demonstrationsprojektets roll i framväxten av ny teknik: Fallstudier av två vindkraftprojekt

This report describes a synchronous machine model with magnetic saturation in d-axis, neutralconnection and electrical exciter interface for the transient simulator PSCAD/EMTDC. It hasbeen designed and verified in comparison to the regular machine model in EMTDC.The performance of the model is very good when incorporating a linear as well as a saturatedmagnetising inductance. The dynamic deviation is only thousandths to ten thousandths perunit. By using a cubic interpolation of the saturation curve, the model gives a good representationof the saturation effect. The open source code implementation of the synchronousmachine model gives the possibility to easily adapt the model to specific requirements.The derived model makes it possible to simulate a synchronous machine with its excitationsystems, e.g.

Ruttplanering : Retursystem för pantade PET-flaskor och aluminiumburkar

This report is the final part within our education, Industrial Organization and Economy focusing on Logistics and Management at Jönköping School of Engineering. The aim with this report is to coordinate recycle drives for deposited aluminum-cans and bottles collected from grocery stores within Jönköping county and locality.In the present situation both aluminum cans and bottles filled with drinks are distributed to the grocery stores by the brewery?s own distributers. At the same time as they supply the drinks they also discharge the grocery stores units with restored aluminumcans and bottles. To make it easier for the grocery stores to handle the goods in the future, all distribution of drinks ought to be directly delivered to the grocery stores own separate central warehouse.

Estetiska lärprocesser och visuell kommunikation : En metodtriangulering för att integrera dubbla perspektiv på K3, Malmö Högskola

Aim: The study aims to investigate the distribution of grades between students in a practical subject and in a theoretical subject.The problem:What is the grade distribution in physical education and mathematics, with respect to gender, socioeconomic background, parental education, ethnicity, and physical activity?Method:To answer the aim of the study a quantitative method was chosen. As the collection method used was questionnaires to 620 students in the 9th grade in Stockholm. Of the 620 questionnaires, 597 questionnaires were used for the static analysis. The method of analysis used cross tables and logistic regression analysis.

El-rollator

Our examination project has been to develop today?s existing walking frames and make them more exiting and user friendly for tomorrow?s users.The use of a walking frame today makes it easier for a person with a movement difficulty in different extent. It makes it easier with their living condition and the user get a more movement easier life where they can take care of the daily chores without any help from the society or the family members.With our product we get a product that not only makes it easier for the user to get out and get forward. We help the user to get forward where they often would have difficulties to get forward. An example is where its more steeper parts where it could be more difficult to get up or down and even with more difficult foundation due to bad weather.

Optimering av ultraljudssändare- och mottagare avseende räckvidd, strålningsvinkel och energiförbrukning

Embedded Systems Lab at Umeå University is currently part of a research project with the purpose to examine the behavior of dairy cows inside a barn. Each cow needs to be tracked with a precision of 50 cm, and since GPS-technique has poor functionality at indoor environments, an indoor positioning system needs to be developed.Embedded Systems Lab has already developed an indoor positioning system using IR-light and radio, but since this system demands extensive infrastructure and is rather expensive, an alternate positioning system using ultrasonic pulses and radio is being examined.In this report the range, beam angle and current consumption of ultrasonic transmitters- and receivers are investigated. Three different driver stages for the transmitter is tested, and two amplifier solutions for the receiver. The report also describes how the length of the transmitted ultrasonic pulse affects the received signal, accessibility of a ?shadowed? signal, and the effect of different sound frequency..

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