Sökresultat:
605 Uppsatser om Heat sink - Sida 31 av 41
Tilla?mpning och simulering av naturlig ventilation : Potential fo?r utnyttjande i kontorsrum
Mechanical ventilation is the most common type ofventilation in newly constructed office buildings. Therehas been an interest to utilize natural ventilationinstead of mechanical ventilation among architects andHVAC consultants in recent years. This is due to thesize of mechanical ventilation systems, which arespace consuming. The mechanical ventilation system isalso complex and requires maintenance. Furthermore,the fan uses a considerable amount of energy.
Vattensänkningar : en analys av orsaker och effekter
There are records of lowering of the water level in a lot of the Swedish lakes from the middleof the 1700th century. The aim was gaining more areable land to meet the needs of more foodto support the expanding population. In areas with top soil which contents of clay or loam asin the southwest of Scania in southern Sweden this was proven to be a successful wayexpanding the total outcome of the harvest.The studied area in the northeast of Scania, though, consists of morain with a lot of mires -much less nutritious conditions. When the water level is lowered the atmosphere gets accessto the peat. The dissolving of the organic matter that has been suppressed by the lack ofoxygene below water level continues.
Följdeffekter av olika användningssätt för vedråvara : en ekonomisk studie
Since the turn of the millennium a sharp increase in the interest for bio energy has been observed. Important reasons for this growing interest can be due to the fact that fossil fuels are a finite resource. A net discharge of greenhouse gases occur when fossil fuels are burned. The discharge of greenhouse gases are considered to be the main reason to the greenhouse effect. Means of control to increase the use of bio energy has been introduced and, as intended, the use of bio energy has increased.
As a result of the legal provisions the ability to pay for bio energy has increased, which the forest industry view as a problem.
DYNAMIKEN OCH EFFEKTEN AV MARINA V?RMEB?LJOR P? TROPISKA KORALLER (SCLERACTINIA)
Marine heatwaves (MHW) have become increasingly common in recent decades due to greenhouse gas emissions that have caused climate change. A marine heatwave is when the sea surface temperature rises, which damage many different ecosystems in the sea. One ecosystem that is sensitive to temperature changes is tropical coral reefs, which are at risk of bleaching during marine heatwaves. Coral bleaching is when its symbionts leave the coral and they lose their color, while also starving to death as they lose their food source. The purpose of this report was therefore to investigate what the connection between marine heatwaves and coral bleaching looks like, and to see if there are any geographical differences.
Mekaniskt brandsläckningssystem
Electrolux Laundry Systems is the world leader in manufacturing professional laundry equipment.The machines are used in the hotel sector, elderly care, in multifamily houses, laundry bars, and incommercial and institutional laundries.If there is oil or grease left in the clothes after washing may the heat from the dryer cause a chemicalreaction. This reaction may, under certain circumstances cause a fire inside the drum. Competitors toElectrolux has developed its own systems that extinguishes fire inside a tumble dryer and customershave expressed desire to purchase a fire-extinguishing system. Therefore, the project team receivedthe task by Electrolux to develop a fire-extinguishing system that extinguishes a fire in a tumbledryer.The purpose of the project has been to develop a system that both detects and responds to fire in anindustrial tumble dryer to meet the competitors and to satisfy customers' requirements.The goal was to develop a fire-extinguishing system for Electrolux Laundry Systems and develop afully functioning prototype.The project began with information searches on a variety of methods to both detect and extinguish afire. Subsequently, a number of different methods were used to develop a final solution and make aprototype.The result of the project is a fire-extinguishing system that extinguishes a fire inside a dryer.
Analys av hur byggnadens höjd påverkar energiförbrukningen i flerbostads- och kontorshus
This diploma work has been carried out in collaboration with the building contractor Sh Bygg Fastighetsutveckling AB in Uppsala with the intention to investigate how the height of a building affects various energy aspects such as transmission losses, infiltration, and the specific energy usage. Three different reference objects have been studied. The reference objects have been simulated for four different heights in the calculation program VIP-Energy.The results show that an increase in floor number can lead to both advantages and disadvantages. As the number of floors increases, transmission losses per square meter floor area decreases. However, as the height of the building increases, the reduction rate decreases.
The possible role of transmissible gastroenteritis virus (TGE) and porcine respiratory corona virus (PRCV) in the mortality of Ugandan back-yard piglets
In Uganda, small scale pig production plays a major role for households to earn a living and to secure their access to meat. Piglet mortality due to diar-rhoea-related dieseases is high. In an attempt to understand the underlying causes for this high mortality this study aims to investigate the role of trans-missible gastroenteritis virus (TGEV) and is a part of a larger project con-ducted at Makerere university in Uganda.
A complicating factor in this investigation is the porcine respiratory corona-virus (PRCV), a stabile mutant form of the TGE virus. The occurrence of this virus had shown to alter the impact of TGEV in e.g. Europe and North Amer-ica.
Lantbruket som energiproducent : tekniska, ekonomiska och miljömässiga förutsättningar för fjärrvärmeproduktion med lokalt skogsbränsle
A third party access to district heating networks has been proposed in Sweden, to increase the competition
on the district heating market. Such third party access could create opportunities for the agricultural sector
as an energy producer. This study describes the technical, economical and environmental prerequisites for a farmer cluster to build and run a heating plant, fueled with local wood fuel.
The heating plant in the described scenario is 8 MW and will supply a village of 1000 houses, and is fueled with wood chips exclusively. Supplying a heating plant with fuel puts high demands on the logistics, since there need to be a continuous flow of fuel. In the scenario, wood residues from felling and thinning is stored in stacks in the forest, and a few times a year chipped and transported to a storage area at the heating plant.
In the study, an estimation of the profitability has been made by estimating the cost of the investment,
personnel, operating and maintenance costs and costs for the fuel and ash handling.
Inflytande av sommarväder på kornas val att vara på bete eller inne dagtid i en besättning, samt studier av andningsfrekvens och yttemperatur hos fokaldjur :
SAMMANFATTNING
När man i tidigare undersökningar studerat betesgång för mjölkkor har klimatet på betet inte
beaktats. En höglakterande ko producerar mycket värme som hon måste avge till sin
omgivning för att kunna bibehålla sin kroppstemperatur. De sätt som djuret kan avge värme
på är begränsade och påverkas av flera klimatfaktorer samt djurets genetiska och biologiska
förutsättningar.
Antalet dagar som registreringar gjordes under denna studie blev av flera olika anledningar få,
18 dagar. Klimatet utomhus under studien registrerat som globtemperatur varierade från 22,4
till 34,7ºC.
Då djurskyddslagen skall främja djurens hälsa och djurets naturliga beteende fick en grupp
126 höglakterande kor möjlighet att välja uppehållsplats under tiden 26 juli till 11 augusti.
2004. Korna fördes ut på betet vid niotiden på förmiddagen och var därefter fria att gå in och
ur stallet efter egen vilja tills de togs in för kvällsmjölkning omkring klockan tre
påeftermiddagen.
Vattendraget på Kåbo golfbana : en kartläggning som ett steg i golfklubbens miljöarbete
This degree project studied surface waters on Kåbo Golf Course in Uppsala, Sweden, with the aim of determining the status of the water and how it is affected by the activities of the golf club, and to obtain suggestions of measures to create better conditions for the water environment on and around the golf course. The project forms part of the environmental protection work of Kåbo Golf Club, which is working towards achieving environmental certification from the Swedish Golf Association (SGF).
The study is based on literature studies and quantitative and qualitative field studies of water on the golf course, with the focus on environmental factors identified as being important for the golf industry and on strategic environmental goals developed by SGF.
The number of open water bodies in the Swedish landscape has substantially declined during
the past 200 years, so it is important to save those that remain. This study showed that the surface water at Kåbo Golf Course is an important element in the surroundings since the area contains few wetlands, which can be a habitat for large numbers of species. The stream and ponds on Kåbo Golf Course also have the important function of serving as water hazards in the game and adding difficulty and variety to the course. Since Kåbo Golf Club wants its surface waters to look aesthetically appealing, extensive algal growth and drying up of ponds during parts of the year are regarded as problems.
Småskaligt vattenkraftverk i Nyköpingsån
Interest in alternative energies is high in Sweden today, particularly in the agricultural sector. According to the Swedish lantbruksbarometern (2009), almost all respondents consider the use of some form of alternative energy from the farm. While interest in alternative energies is large, attention to the alternative energy straw has fallen and is almost nowhere mentioned in the literature today. Three years ago, in the Lantbruksbarometern nearly 44% of the farmers would be willing to invest in straw as heating system on the farm. How do the farmers decide to invest in alternative energies? With this information a problem is presented for this paper.
En analys av centralkylan i Slakthusområdet i Stockholm
In Stockholm, Johanneshov the Slaughterhouse area (Slakthusområdet) can be found. A number of companies have gathered there providing the Stockholmers with meat products. This area has a great need for cooling to supply large cold storages. To facilitate this, a central cooling system has been built, supplying the area with effective and safe cooling.The aim of this master thesis study is to give hints to energy efficient and reliable changes that can be put in place at a low marginal cost depending on the future activities in the area. The suggested changes will be presented to the company Bravida (managing the system), which also desires a deeper understanding of the energy flows through the central cooling system.Firstly visiting the site with proper guidance, we have then tried to understand the function of the system including which machines and media that are used.
Funktionell validering av mutation i PUS-1 i en patient med mitokondriell sjukdom
With the climate change issues growing in importance on the social agenda, the field of urban masterplanning is of no exception when it comes to minimizing the carbon footprint in a variety of projects. The aim of this thesis has been to prepare the Carbon Critical Masterplanning tool, a software plugin for carbon dioxide emissions assessment developed by Atkins, to be used in Swedish conditions. The main targets were to improve the areas of the tool associated with energy conversion and renewable energy sources, and to test the tool in a real case. A planned construction of a new campus in Albano, Stockholm was chosen for the pilot study. A 3D model was built in the tool and the carbon footprint was calculated for a variety of combinations for energy supply to the future area.
Laserinkopplingselement För XFEL Laser Heater : Från Idé Till Färdig Produkt I Designstadie
Uppsala University is involved in a large international collaborationto build the Laser heater system for the European Xray Free-electronlaser in Hamburg, Germany. In this thesis I describe a laser incouplingdevice into the vacuum chamber of this laser heater all the way fromthe specifications to a completed design.The laser heater is a very important part of the XFEL and thepart described here is a part of the vacuum system needed to couplean external laser into the electron vacuum system and align it withthe electron bunches in order to heat them. The task was started by studying the literature about the basic theory andthe design of vacuum systems. After this study and collection of ideaswith colleagues I started to prepare different concepts to solve thetask. The ideas can be put into two categories, in one case the couplingmirror is located inside the vacuum chamber and in the second caseoutside.
DFM för Lasersvetsning
The purpose with this thesis was to develop a designguideline which will simplify the development of new products that will be laser welded. The need for this thesis has come forward from the quality problems that Volvo Construction Equipment, Components Division is having with their laser welding manufacturing unit. The reason for the problems emerges from the bad communication between the development unit and the manufacturing unit within the company when the products produced today was developed. This resulted in products that were hard to and in some cases almost impossible to weld. To avoid these problems from occurring again it was needed to gather the experiences within this area and compile it and present in a brief a pedagogical manner. The information for the groundwork of our results has been gathered by interviews of several key persons in Volvo Construction Equipment, Components Division.