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3910 Uppsatser om Energy production - Sida 27 av 261
Kvalitetskontroll av trafikmätningssystem ? En studie om noggrannheten hos induktiv slinga, slang, KomFram, video och radar i olika trafikmiljöer
This report is a study in voltagelevel in connection with regeneration of brake energy from the tramtype M31 in Gothenburg.In the act of braking, the tram M31 uses electrical braking where the electrical motors generates energy and if possible send it back to the overheadline, where other trams in the nearby can use this regenerated energy for its own driving force. In cases where no other energyconsumers are located in the same section, there is a resistance witch task is to convert this energy into heat. The regulation of this resistance appears to cause an increase in the voltagelevel into far too high levels.Investigations of the trams regulationequipment and its construction have been done. Further have measurements on the overheadline been performed in order to map the voltagevariations during a longer period of time.The result have been showing that the voltagelevel during regeneration often is as high as 880V-920V, more extreme values have not been observed in a large scale. The values are especially high compared to the nominal voltagelevel.
Bakteriell produktion i humösa istäckta sjöar i norra Sverige
The main purposes of this study were to 1) quantify bacterial production in winter during ice conditions, and 2) to compare these production measures with values measured from summer and open water conditions in three humic lakes situated in northern Sweden. Another purpose of this study was to 3) examine whether clear-cutting significantly affected bacterial production or water chemistry in two lakes situated in catchments were a large part of the forest had been removed through logging compared to an undisturbed reference lake. In winter (March/April 2014), the bacterial production ranged from 0, 7 - 2, 2 µgC/L/day and in the summer of 2013 the production values was 4 ? 10 times higher. The main reason for lower bacterial production in winter was ascribed to lower water temperatures as well as to older and more recalcitrant DOC, as there were no significant differences in total dissolved nitrogen or DOC concentration or -quality, that could explain a lower production compared to summer.
Den allvarsamma leken : Om källan till mening i arbetet
Based on 30 years of work experience in TV and film production, I have made a phenomenological analysis of my perception of meaning in work - how it arises and how it is undermined. The story starts in my experience of early professional film making in the 1980's and describes how a change to work in TV production required the development of a new professional identity. The text also illustrates how as a female director I have managed my role in a male dominated and structured work environment. Being defined as an exception from the male norm has pushed me towards femininist reflection and the need to redefine my own work role - the generally accepted view having felt uncomfortable. An analysis of structural change in TV and film production shows how market pressures and ways of thought have increasingly invaded cultural endeavour. Professional spheres of influence are weakened, while developments in the media are characterised by a commercialism which encroaches more and more upon artistic, spiritual and moral values. This attitude, where quality is in retreat, has transformedprogramme makers from creative originators into becoming suppliers of raw material in a factory- like process geared to produce great volume at low cost.The aim of this essay is to show how changes in society and in TV and film making have affected my perception of my work.
Teknisk undersökning : Rötgaskammare för småskalig biogasproduktion
Biogas mainly consists of methane and carbon dioxide, where methane is theenergy-rich gas, and is naturally created when organic matter breaks down in absenceof oxygen, also known as anaerobic digestion. A biogas plant re-creates the anaerobicconditions inside a digester where the organic substrate is fed into and digests toproduce biogas. The gas is then used to produce energy by combustion and can beseen as a completely renewable fuel.Today, energy from biogas is used primarily by major stakeholders such asmunicipalities and thus the plants become very large with high investment- andconstruction costs. There are currently few small plants in Sweden, even though thepotential for agriculture and medium-sized to smaller farms to become self-sufficientin terms of electricity and heat is great. Farms have a natural stock of digestibleorganic material in form of manure or crops for example, which are constantlyavailable.
Elevers uppfattningar om kunskap, motivation och undervisning kopplat till SO-ämnena
The purpose of this study was to investigate the association between physical activity and perceived stress, energy and musculoskeletal disorders among office-workers and warehouse-workers and also to see if there were any differences depending on work-place and gender. The method that was used to collect data was three different validated questionnaires that measured stress and energy (the Stress-Energy questionnaire), musculoskeletal disorders (intensity and localization of pain, a Pain Drawing questionnaire with a VAS-scale) and physical activity (IPAQ ? the short version). Eighty-eight workers participated in the study. Forty-seven of them were office-workers and forty-one were warehouse-workers.
Korsplattformskommunikation med Bluetooth Low Energy
This project investigated the current market regarding wireless net and the communication between the tools used for diagnostics/maintenance and an embedded system. Based on documentation obtained through interviews a demo system was created based on Bluetooth Low Energy (BLE) communication between an embedded system and an Android device.This report intends to describe the tools and methods used in the design of the demo system and the result of an analysis of the BLE communication.Bluetooth Low Energy is an exciting protocol with wide applicability within the industrial field. This project investigated the communicational possibilities between a Smartphone and a Raspberry Pi and based on the results that emerged the conclusion can be drawn that BLE is a protocol with many beneficial applications within industrial IT..
Småskalig vattenkraft : Dagsläge och framtidsplaner
This study focuses on small scale hydropower in Sweden. This means plants with a capacity of up to 10 MW. The study has a special focus on plants with a capacity up to 2 MW. The study has three aims. It strives to describe the small-scale hydroelectric industry in Sweden.
Energianalys av MVG-gallerian, samt en jämförelse av beräkningsprogram
På uppdrag av Sweco Systems i Umeå har detta examensarbete utförts under våren 2013. Syftet var att undersöka huruvida något av de energiberäknings-program som används på företaget kan anses vara lämpligt vid energikartläggningar av befintliga fastigheter.Inledningsvis utfördes en energikartläggning av fastigheten Odin 12 i Umeå, som i huvudsak utgörs av gallerian MVG. Med resultaten från denna energikartläggning som grund beräknades därefter fastighetens energianvändning i två olika program ? VIP-Energy och IDA Indoor Climate and Energy.Resultaten från den inledande kartläggningen visar att fastigheten har ett lågt behov av fjärrvärme, vilket förklaras av fastighetens höga elförbrukning. Den stora användningen av el genererar stora mängder internvärme som, förutom att sänka fjärrvärmebehovet, även medför att fastigheten under hela året har ett kylbehov.Utvärderingen av de två beräkningsprogrammen visar att VIP-Energy är ett lämpligt program att använda vid energikartläggningar.
Hur byggnadsdetaljer ändrar fasadens uttryck
An energy study has been performed on two blocks in an area called Gävle Strand. The buildings are owned by a tenant-owner?s association called brf Carolina and were built by the company Skanska 2008. The builder as well as brf Carolina are pussled by the fact that electricity use is higher than expected while heating is less. Skanska is also very interested in finding out how much heat recovery from stale exhaust air through a geo-thermal heat pump is contributing to the general heating requirement and energy balance in four out of the ten buildings located on the properties.To find possible answers to the higher electricity use a literature survey on user behaviour was conducted.
Stockholms Energiframtid : En backcastingstudie för ett fossilbränslefritt Stockholms län 2050
This study concerns the energy future of the county of Stockholm up until 2050 and describes how the energy consumption can be compared to today with the use of scenario methodology. Within energy future studies the backcasting approach is well known and has been put to use in this study. Due to the characteristics of backcasting the study is self-fulfilling, i.e. the future energy scenarios presented in this study satisfy the targets set up in this study. In the light of what may be the largest challenge of our time ? the climate change - the aim of this study is to describe how the energy consumption in a fossil fuel free Stockholm county in the year of 2050 may be.
Hälsobeteende bland sjuksköterskor och undersköterskor : En studie om oregelbundna arbetstider på Ålands hälso- och sjukvård
In our everyday life we are faced with many choices that have consequences on the environment. One of these is the food we choose to eat since food production has a big impact on the environment. In organic production the aim is to have a natural production process, where environmental impacts are minimized. By choosing organic food it is therefore possible to contribute to a better environment. A large number of meals are served every day in the public sector, which makes it an important player in the consumer sector that could make a major difference for the environment..
Elever som inte når målen i de samhällsorienterande ämnena : Orsaker och insatser i grundskolans tidigare åldrar
The purpose of this study was to investigate the association between physical activity and perceived stress, energy and musculoskeletal disorders among office-workers and warehouse-workers and also to see if there were any differences depending on work-place and gender. The method that was used to collect data was three different validated questionnaires that measured stress and energy (the Stress-Energy questionnaire), musculoskeletal disorders (intensity and localization of pain, a Pain Drawing questionnaire with a VAS-scale) and physical activity (IPAQ ? the short version). Eighty-eight workers participated in the study. Forty-seven of them were office-workers and forty-one were warehouse-workers.
Värmeförluster vid utvändigt placerade ventilationssystem
To be able to handle tomorrows need for limited energy consumption we need to reduce our use of energy. The building sector stands for around 40 % of all energy consumption in the society. The government has put up a goal to reduce the energy consumption in our buildings with 20 % by year 2020 and 50 % by year 2050 compared with year 1995. To be able to do reach that goal we need a more energy efficient building stock.The main part of the energy used in our buildings is used for space heating. By installing ventilation systems with heat recovery on the exhaust air it is possible to use the heat-energy in the exhaust air to warm up the incoming air.
Biogasproduktion genom tvåstegsrötning av drankvatten
During the 19-century a global warming has been observed, which includes increases in global air and ocean temperatures, widespread melting of ice and snow, and rising global sea level. There is a clear connection between emissions of greenhouse gases caused by the human and the increase in temperature. Climatic changes caused by global warming can be stopped trough decreased emission of fossil fuels, for example by an increased use of biogas. Biogas is a renewable energy source which is produced through anaerobic (oxygen free) digestion of organic material. The gas is a mixture of methane (CH4) and carbon dioxide (CO2) and can be among others used as fuel in vehicles.
Till framtida utvecklare
The report is about efficiency of a current production group where there is no clear production flow and there are some buffers between the operations. The efficiency is done with the help of a tool that is calledWork process of flow production which is used by Atlas Copco CTO. The most obviously results are that the lead time drops from 25 hours to 425 minutes and that the balancing loss decreases from 85 % to 8 %. The report focus on decreasing transports, decreasing buffers, more reliability in lead time and quality. And a more stimulating labour content for the workers is another result..