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2917 Uppsatser om Energy and resource consumption - Sida 45 av 195

Analys av systemfaktorers påverkan på tillförlitligheten i distributionsnät

In this master thesis outage statistics covering tree years from two distribution grids are analyzed with the purpose to deduce which factors yield outages. The statistics are extensive therefore allowing in-depth analysis of both customer and system related factors. From this starting point and as a model of explanation energy not supplied is studied as the consequence and the measurement of the inconvenience caused by outages. Different methods for calculating energy not supplied are developed and studied and put in comparison to the method used in Network Performance Assessment Model, which is the Swedish frame work for regulating electricity distribution.Analysis of the outage statistics show a relation between the type category of customer and outages that can be deduced to the variance and the density associated with that customer category. Prioritization of different customer categories is elevated also in this aspect.

Miljöbedömning av olika behandlingsmetoder för organiskt hushållsavfall, slakteriavfall och flytgödsel

Organic material used for biogas production can also undergo other treatments. The emissions and impact from the different treatments are evaluated in this environmental assessment, with a focus on energy and climate. The materials included in the study are organic household waste, slaughterhouse waste and liquid manure. Other than biogas production, the possible treatments for organic household waste and slaughterhouse waste are incineration and composting, and for liquid manure storing and spreading. The analysis is based on data and information from current and relevant literature, and relates to the conditions in the Swedish energy system.

Vindkraftens framtida scenarier

In several countries that have been early in the development of wind farms, there is today a second hand market for the used wind turbines. The European Union (EU) has established a waste hierarchy in order to minimize throwaway mentality. The second hand market is a part of this as the steps are to minimize, reuse, recycle, extract energy and landfill.In order to promote the development of renewable energy, there are energy certificates for the producers that provide it, wind power being one type of renewable energy. After 15 years the energy certificates for a specific wind turbine are no longer paid, and after that there are several different scenarios for the wind turbine. The scenarios investigated in this bachelor?s thesis are export of the wind turbine to countries that are not as far along as Sweden in their development towards renewable energy, selling in Sweden to individuals, and recycling of the wind turbine, as it mostly consists of metals and therefore is recyclable.

Från alger till biodiesel - Den italienska drömmen?

This project aims to investigate whether algae can be used for biodiesel production in Italy. Algaes are a good option since they are fast growing and do not occupy arable land. The aspects that have been considered are growing, harvesting, which algae strain that is most suitable, extraction of oil, the production of biodiesel and where in Italy this could be possible due to climate. Cost? and energy calculations have been made to investigate if biodiesel produced from algae would be profitable. During the production of biodiesel there are several residues obtained. When the oil has been extracted from the algae, biogas is produced from the residual biomass by anaerobic digestion and then the electricity that can be produced is supplied to the production of biodiesel.

Effekten av olika andelar grovfoder och kraftfoder i foderstaten på mjölkproduktion, välfärd och hälsa hos mjölkkor

Dairy cows transform grass to milk with help from ruminal microorganisms that can digest indigestible fiber in their feed. The digestive system of the cow is adapted to a diet consisting of forage and disorders like acidosis, laminitis and abomasal displacement can occur if the feed contains too much starch. To achieve the highest production possible the cow has to be given a high amount of concentrate or grain as the difference in milk yield is significant, approximately 1000 kg energy corrected milk per cow and year between conventional and organic cows that are fed a lower versus a higher share of forage. If the cow shall be able to eat the same amount of energy from forage as from grain or concentrate the eating- and rumination time gets longer and she might not be able to eat enough, which will result in a lower milk yield and will make it harder for the cow to recover from the negative energy balance that originate from the beginning of the lactation. Fat and in a sense protein content differs also depending on if the cow is given a high or low share of forage..

Utveckling av en ytmonterad fördelningsmätare som underlag för individuell debitering av vattenförbrukning i fastigheter

The master thesis, conducted at Metrima AB, concerns the development of a non-intrusivedistribution meter as a basis for individual tap water billing in apartments.The project is conducted in response to the market interest in individual tap water billing inapartments as an answer to environmental concerns regarding water consumption. Due to thehigh installation cost of traditional water meters, a new method of determining waterconsumption, without having to cut water pipes, is proposed.The proposed method distributes the total water consumption for an apartment complex toindividual apartments according to distribution meters, measuring water run-time, in eachapartment. The water run-time is estimated by measuring the water pipe?s outward vibrationsand temperature changes.A test environment was established and a prototype built, using a tilt- and vibration sensor forvibration sensing and a precision temperature sensor to measure temperature changes. As bothsensors work well in the test environment, further testing was done in 3 apartments for aduration of 5 days.

Effekten av frukostens glykemiska index på energiintag hos barn och ungdomar

Sahlgrenska Academyat University of GothenburgDepartment of Internal Medicine and Clinical NutritionTitle: The effect of the glycemic index of breakfasts in energy intake inchildren and adolescentsAuthor: Charlotte Olofsson, Cornelia Johansson and Maria NordbeckSupervisor: Fredrik BertzExaminer: Ingrid LarssonProgramme: Dietician study programme, 180/240 ECTSType of paper: Examination paper, 15 hpDate: May 16, 2013Background: The glycemic index (GI) and it´s effect on energy intake is a debated subject.Research has been done whether food with lower GI decreases hunger and lowers energyintake, which could be an effective tool to prevent overweight in children and adolescents.Breakfast eating is successful for maintaining a healthy weight and it´s therefore interesting tosee if the quality of the carbohydrates matters.Objective: To evaluate the scientific evidence regarding the effect of GI of breakfasts inchildren?s and adolescents energy intake.Search strategy: To find relevant articles, a systematic literature search was made in thedatabases PubMed, Scopus and Cochrane. Search terms that were used were: breakfast,breakfast quality, children, glycemic index, energy intake, obesity.Selection criteria: Randomized controlled trials and cohort trials, breakfast eatingindividuals, children and adolescents under 18 years old, reported glycemic index. Outcomemeasurements: Energy intake.Data collection and analysis: Six original articles met the inclusion criteria and werereviewed by the SBU audit template for randomized and controlled studies. There after onearticle was excluded because of very low quality of the study.

Automatiskt avvägningssystem för obemannad undervattensfarkost

This master thesis work was done at Saab Underwater Systems AB, a company at the cutting edge of underwater technology. Here torpedoes and other underwater vehicles are developed and manufactured. The major customers are navies of different countries, mostly the Swedish navy. The aim of this master thesis is to develop, construct and evaluate an automatic Trim System for Unmanned Underwater Vehicles. The task of the system is to change the position of the centre of mass and the vehicle?s total mass or volume.

Tro, hopp och utsatthet

The thesis objective was to study the partnership between the municipality of Gothenburg and three nonprofit organizations concerning the mobile EU-citizens. The study examines how the EU-enlargement affected Sweden and eventually the municipality of Gothenburg, and how Gothenburg responded to the new situation regarding the target group. The thesis contains one case study and the empirical data are based on semi structured interviews with politicians and officials from both the public- and the nonprofit sector. The results were screened with New Institutional Theory, Resource Dependence Theory and Decision Making Theory: Rule Following. The theories were used to locate any type of isomorphism, resource dependence and rule following in the partnership.

Utökning av PHP

Detta examensarbete är gjort på uppdrag av ett företag som heter IT Resource AB i Årjäng Värmland.Målet med detta examensarbete var att skapa ett API till PHP som skall utöka PHPs funktionalitet. APIet skall förenkla samt effektivisera IT Resource ABs arbete med att utveckla webbapplikationer. Den förenkling samt effektivisering som APIet erbjuder är möjligheten att återanvända funktioner samt att man enkelt kan lägga till nya funktioner i APIet vid behov.Den funktionalitet som APIet kommer att tillhandahålla är en förbättrad hantering av variabler och strängar som genereras från en webbsida skriven i PHP. Med en förbättrad hantering menas bland annat att det skall vara möjligt att lagra variabler och strängar från en webbsida skriven i PHP.Det skapade APIet består av 2 byggstenar, en klient och en server. Klienten i klient/serversystemet är en extern modul innehållande funktionalitet för kommunikation med både PHP och servern.

Studie av energianvändningen på Spira förskola: En jämförande studie av faktiskt och simulerad energianvändning samt en parameterstudie av ingående data vid simuleringar av energianvändning

I detta arbete har den faktiska och simulerade energianvändningen på Spira förskola i Luleå undersökts. Den faktiska specifika normalårskorrigerade energianvändningen fastställdes till 121,4 kWh/kvm år. Vid projektering av förskolan uppskattades den specifika energianvändningen med hjälp av simuleringsprogrammet VIP-Energy till 78,5 kWh/m2 år. Därmed översteg den verkliga användningen den simulerade med 54,6 %.En parameterstudie av indata till simuleringsprogramet har också genomförts med avsikt att fastställa den totala förändringen i energianvändning då indata ändras. Följande parametrar har studerats;?Drifttid hos ventilationssystemet?Horisontvinkel?Inomhustemperatur?Klimatzonen?Kvot mellan till- och frånluft?Luftomsättning för ventilationssystemet?Solreflektion från omgivande mark?Temperaturverkningsgrad?Vindhastighet?Vridning av byggnadenNyckeltal som kan användas för att snabbt uppskatta påverkan på den totala energianvändningen har också sammanställts för majoriteten av de studerade parametrarna.

Värmeöverföring i bergvärmesystem : En numerisk analys av den ringformade koaxiala borrhålsvärmeväxlaren

The borehole heat exchangers of today suffer from poor thermal and hydrodynamic performance. The purpose of this thesis is to improve the performance of ground source heat pump systems and thermal energy storages by increasing the energy efficiency of the borehole heat exchangers. For this reason, the annular coaxial borehole heat exchanger (CBHE) has been analyzed. This type of heat exchanger is interesting in terms of both thermal and hydrodynamic performance. A model has been set up in the program Comsol Multiphysics in order to investigate the heat transfer characteristics along the borehole.

Beräkning av värmeförluster och energieffektivisering av elbussar

The ?civilized? world is in need of fossil fuel in order to function. Hybricon AB is a company in Umeå that is developing a technology that hopefully can reduce parts of this need. They are currently testing their two electrical busses (with Hybrid backup) in city traffic on the roads of Umeå in cooperation with the county of Umeå.                               The busses are originally diesel-busses, but the diesel motor has been replaced with two electrical hub-motors with a power of 145 kW each that are powered by batteries.The batteries are charged at the end station after each route. In case the batteries should run low on capacity during driving, they can be recharged by the so called genset.

Design för ett hållbart samhälle : En undersökning om hållbar design samt dess drivkrafter och hinder

Sustainable design - a study on sustainable design and its incentives and barriersThe purpose of this study was to investigate the incentives and barriers existing within companies focusing on eco-design. The aim was also to examine the consumers? thoughts on eco-design and sustainable products. A further aim was to try to concretize important lessons for future work on sustainable production and consumption. Two methods were used for completing this study; a literature study and a practical study consisting of interviews with companies focusing on eco-design and a survey among students.

Utvärdering av inomhuslokalisering med Bluetooth Low Energy

Wireless communication is becoming more common, a relatively new technology within the area is Bluetooth Low Energy. It?s been developed to be energy efficient and in regard to compatibility. Alongside the growth of wireless technology, scientists and companies are looking for new areas of use. One of these is localization, which means to determine the position of a moving device with the use of stationary devices, an example of this would be GPS.This report means to evaluate indoor localization using Bluetooth Low Energy and was made for Combitech AB in Jönköping.

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