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1467 Uppsatser om Feed efficiency - Sida 28 av 98

Adaptiv temperaturreglering av bostadshus

The control of indoor temperature must be able to handle large time constants and both measureable disturbances like outdoor temperature, and non-measurable disturbances, like waste heat from appliances. Due to cheaper microcontrollers (small computers with designated tasks) with better performance, more advanced and computation-demanding methods for control can be used.In this thesis, Generalized Predictive Control (GPC) has been implemented and tested on a theoretically derived model of a house. GPC states that a model of the system is estimated in every sample, and the control is carried out simultaneously, based on predictions of the model. Disturbances like solar radiation can be estimated and used in the control as well. The control signals are determined by quadratic programming, which makes it possible to consider conditions, for example limitations on the control signals.GPC requires a number of parameters to be defined, like model order and control signal penalty, but is relatively robust for variations in them.

Energieffektivisering genom förvärmning av flis till kokare med sekundärvärme

The Swedish pulp and paper industry meets higher demand for energy efficiencyi mprovements with increasing energy prices and changes in the Swedish renewable energy certificate system. One action of energy efficiency improvement is by using secondary heat, that otherwise would have been treated as waste heat, for use in a system with lower temperature demands. The aim of this Master´s thesis is to identify possible secondary heat sources in a typical Swedish pulp and paper mill and to investigate what economic benefits the secondary heat will provide when being used for pre heating of wood chips to a kraft digester.The Master´s thesis focuses on three secondary heat sources; dry warm air, warm water and moisture saturated warm air located inside the pulp or paper mill. Two types of kraft digesters are simulated within this study, a typical Scandinavian digester and a modern twin vessel steam phase digester.Due to quality aspects and low temperature level drying is the drying technology with dry warm air rejected. Using warm water in direct contact with wood chips increases the quantity of water to the evaporation plant and thus reduced pulp or paper production and is therefore also rejected.

Etiologi och patogenes för benign prostatahyperplasi hos hund

This literature review summarizes available data on infection with the parasitic roundworm, Ascaridia galli, as a cause of disease in poultry, including the consequences of a conversion to alternative production systems. Ascaridia galli has a direct life cycle with resistant eggs that survive and are easily spread in the environment, especially in systems with bedding materials where the faecal contact is high. The infection is usually subclinical but depending on the infection dose, the symptoms range from weight loss and diarrhea to mortality. Factors such as the feed composition and genetic variation among different hybrids clearly affect the establishment rate of the infection. Ascaridia galli will probably become an increasing problem, with a shift from the traditional battery cages to alternative systems where the risk of re-infection is high.

Återvinning av industriell restvärme som värdeskapande process : En fallstudie på SSAB EMEA i Borlänge

The industrial sector accounts for a large share of greenhouse gas emissions. To reduce its negative impact on the environment is crucial in the quest for a sustainable future. In discussions of the industrial sector's impact on the environment guidelines have been highlighted as a tool to assist the industries in their efforts to change the relationship between the consumption of energy and production. This by improving energy efficiency and a shift to the best available technology. During the past 30 years the steel industry has reduced its energy consumption per ton of steel produced by 50 percent.

?Det var en tyst kamp? : En ekokritisk analys om utvandring och fo?ra?nderliga system i Vilhelm Mobergs Utvandrarna

The purpose of this essay is to do an ecocritical reading of Vilhelm Moberg?s The Emi-grants from 1949. By asking and answering the three following questions; How does a system present itself, What are the different reasons for emigration; Why does differentsystem fit some well and some not.By using two articles from Green Planets - Ecology and Science Fiction to illus-trate two different views; Different parts value in an ekosystem and The Ship as an ecosystem. I have also created, based on the literary text four different terms concern-ing the dynamic system; Stable, Static, Unstable and Collapsing systems. I have found that all system goes through changes, some drastic, that changes the way the parts of the systems fit with in it.

Möjligheter till uppfödning och utsättning av fasaner och gräsänder på Björnslunds gård :

This study treats the possibility of breeding mallards and pheasants on our own farm, Björnslund. From the beginning I considered to breed them from eggs to adults but after visiting several breeders I changed my mind. It seemed to be a lot of work with no economic profit in comparison with buying already hatched birds and then feed them to adults. If the business shall be profitable I have to be soll the hunting for the birds and then sell the dead birds to game purchasers. There are also calculations that show which price you have to charge for the hunting that will give a positive result. Another possibility is to own a slaughterhouse and sell the meat to restaurants and supermarkets.

 Solenergi En del i ett långsiktigt, hållbart byggande

The sun is essential to life on earth and no matter where you are, there is a constant need ofenergy. Nearly 800 000 years ago man learned for the first time to use fire in a controlled way.Since then, fire has given us the opportunity to inhabit places despite a cold climate. In Swedenthe resident sector accounts for a major part of the total consumption of energy. In a time whenenvironmental issues and greenhouse effects are increasing, we also see a future of rising energyprices. With this perspective, we have in this bachelor thesis in the Building Environment at theRoyal Institute of Technology, KTH, in Stockholm decided to focus on the renewable energysource, solar energy.The energy from solar radiation is a free resource and does not have any negative effects uponthe environment.

Methane emissions from Swedish sheep production

The quantity of methane emissions from sheep depend on several factors, for example, the composition of the diet, feed quality, the age of the animals, time of the day and maybe also breed and sex. A comprising literature review was made about which factors that affect the size of emissions. In addition, a questionnaire was sent to two farms, one with a more intensive production system and another with a more extensive system. Inventories of the two farms were made; the rest of the data needed to conduct the study was taken from literature and other sources. Meat produced at the more intensive farm caused emissions of 0.4 kg of methane per kg of bone free meat and the more extensive farm caused emissions of 0.9 kg methane per kg of bone free meat.

Morgondagens effektiva fjärrvärme : En beskrivande litteraturstudie

This report is made as a literature review, focusing on the work done to increase understanding of efficiency in the categories of substations and secondary heating systems, with respect to the deviation from the theoretically possible cooling off in the distribution network as well as the economic benefit that appear. The main purpose of a considerable part of the literature used in this report addresses the issue of identifying individual causes of reduced cooling in district heating systems. These literature resources have been compiled and summarized as part of the report.The technology of district heating is associated with benefits such as better use of the energy in a fuel. This is the case of cogeneration plants where serial generation of electricity and thermal energy increases efficiency compared with the parallel generation where heat is generated locally and electricity is generated centrally. Serial generation thus allows for lower primary energy demand.

Rapportering eller kopiering : En kvantitativ studie av inkomna pressmeddelanden till P4 Kalmar

The aim with this study is to investigate how Swedish public service local radio uses information subsides in the form of press releases. In terms of which entrants gain entrance to the news feed, in which forms and in which subjects. Also we wanted to study how the journalist uses the content in the press releases. To do this we cooperated with the public service radio channel Sveriges radio P4 Kalmar. For 28 days, four weeks, we collected all incoming press releases to the newsroom of P4 Kalmar.

Kvarteret Kajutan - Från lågenergi till plusenergi

Energy and environmental demands regarding buildings have become an increasinglydiscussed topic, both in Sweden and in Europe as a whole. The general trend indicatesthat greater efforts are being put into the energy efficiency of the built environment.There are already numerous examples of houses with a low energy demand, and thenumber of low energy buildings is constantly growing.At the time being, the maximum level for energy demands for housing in Stockholm is110 kWh/m2year, but as soon as next year the limit will be changed to 90. The Swedishagency Energimyndigheten is currently conducting a project to interpret the EU Directiveon the so-called Nearly zero energy buildings, and the preliminary results indicate thatthe level of requirements for purchased energy will end up with about 55 kWh / m2year,which is in line withtoday?s recommendationsfound in FEBY's Kravspecifikation förPassivhus.Starting with a low-energy house in Henriksdalshamnen in Stockholm, we have analyzedvarious energy-efficiency measures and their influence on power and energy needs. Thefinancial aspects associated with the measures have been studied using a model of lifecycle costs.The measures were initially studied individually to give an idea of how much impact theyeach had.

Tekniska möjligheter för artificiell spridning av renlav :

Forestry and reindeer husbandry are entitled to use the same land for their operations. For this reason, conflicts occasionally arise between them. Soil scarification is a forestry operation which has a negative effect on the occurrence of reindeer lichen. Reindeer lichens are of crucial importance to reindeers and reindeer husbandry, especially in the winter when reindeers primarily feed on different lichen species (Cladina spp. and Cetraria spp.).

Rörsvetsning i konceptet Factory-in-a-Box

This Master of Science thesis was a part of Pharmadule Emtungas project to construct a mobile automated cell for welding of carbon steel pipe (Heating, Ventilation and Sanitation). Pharmadule Emtunga is using a modular building concept for building pharmaceutical factories. The modules contain these pipes. The goal of the thesis was to present concepts for technical solutions regarding welding methods and fixtures for the cell. Conceptual models for the cell were made with aid of CAD software.

Effektivisering av arbetsplats : Effektivisering av monteringsplats vid Wigells AB

The work presented in this report is written at IEIs department on Linköping Institute of Technology. The report aims to increase the assembly efficiency at Wigells AB. The report shall be used as a guide for the implementation of changes at other workstations in the company. Together with Träcentrum in Nässjö, Wigells AB has identified the needs of this study and contacted IEI at Linköping Institute of Technology.In order to implement an efficient assembly line at the company, studies on lean production have been made. This theory has been studied and together with our own views and findings at the company we have analyzed the assembly area.Wigells is a small company that manufactures wood furniture.

Effektivitetsparadoxen - En eventstudie av handelsstopp på Stockholmsbörsen mellan 2003 och 2008

A trading halt is a measure conducted by a securities exchange in order to reduce information imbalances between market participants, thus enabling a higher level of market efficiency. A market is said to be efficient when new information concerning a company is instantly reflected in its stock price, implying that abnormal stock returns cannot be systematically achieved in an efficient market. The purpose of this study is to examine the occurrence of abnormal stock returns following trading halts on the Stockholm Stock Exchange. The study is based on a sample of 64 trading halts executed between January 2003 and February 2008. Historical daily prices for stocks subject to trading halts during the period have been gathered from the Datastream Advance database, while information on date and time of trading halts have been collected from the Stockholm Stock Exchange website.

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