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4105 Uppsatser om Calculation model - Sida 18 av 274
Uppvärmning med spannmål och trädbränslen :
This examination work brings up opportunities to invest in a construction for heating with grain
or pellets on farm level.
As example we have chosen Fröberga Gård which is a farm located in Östergötland outside of
Söderköping.
The farm`s residential buildings is to day heated with oil and electricity.
The result of our investigation shows that heating with grain is the best alternative, partly because
of economical issues but also because you can grow the grain on your own farm and by that you
can get better economy in your seed cultivation.
To grow 16 tonne of grain as is needed demand gives a insignificant increase of work.
Further an advantage is that no investment in machines is needed because all the machines witch
is needed already is in use on the farm.
In a situation where a new investment is needed as in the case we studied, is it often profitable to
invest in a integrated furnace. Because all the components are well adapted to each other, and
because that gives a high efficiency.
If you already own a well working furnace is it often most profitable to connect a burner to it.
It is important to know that heating with grain need more work than heating with pellets, because
the high contents of ash in grain.
Even if you choose pellets instead of grain the calculation shows good results.
Because peat is an excellent but fairly untested raw material for pelletsproduction we have
chosen to watch little more on its quality and conductions.
We discovered that peat has a high heating value which makes it possible to raise the heat value
in pellets through mix up peat and wood. Or you can make pellets with only peat and get a pellet
with high heating value. Even the calculation with peatheating shows good results..
3D-modellering i AutoCAD -att skapa en digital huskonstruktion
3D-modelling in AutoCAD This thesis is done in cooperation with LB-Hus in Bromölla, and have aimed to establish a digital AutoCAD model of one of the company?s house types and to find out what opportunities there are to do visualisations in the form of images directly from the programme. Modeling has been carried out so that the very construction of the house is included. Interiors and installations, with the exception of the ventilation system, have been left out in the model. The model has been created with solid models after a comparative study made between solid models and surface models to find out which option in this case was the easiest to handle and took up the least space.
Kylvattenkemikalier i länsvattnet ifrån världshandelsflottan : En approximativ beräkningsmodell för årliga utsläpp av kylvattenkemikalier ifrån världshandelsflottan
Fartyg använder sig av stora dieselmotorer för framdrift och för att producera elektricitet ombord. Motorerna samt diverse kringsystem har behov av kylning och till detta används kemikaliebehandlat vatten i ett slutet kylsystem. Vid tömning och läckage från systemet tenderar det kemikaliebehandlade vattnet att hamna med länsvattnet. Länsvattnet genomgår en reningsprocess innan det pumpas överbord. Denna reningsprocess är inte utformad för att avskilja kemikalier och dessa tenderar att hamna i havet.
Rocchio, Ide, Okapi och BIM : En komparativ studie av fyra metoder för relevance feedback
This thesis compares four relevance feedback methods. The Rocchio and Ide dec-hi algorithms for the vector space model and the binary independence model and Okapi BM25 within the probabilistic framework. This is done in a custom-made Information Retrieval system utilizing a collection containing 131 896 LA-Times articles which is part of the TREC ad-hoc collection. The methods are compared on two grounds, using only the relevance information from the 20 highest ranked documents from an initial search and also by using all available relevance information. Although a significant effect of choice of method could be found on the first ground, post-hoc analysis could not determine any statistically significant differences between the methods where Rocchio, Ide dec-hi and Okapi BM25 performed equivalent.
Värmeåtervinning på förskolan Rymdattacken 1 : En jämförelse av värmeväxlare
In the spring of 2014 Sweco Systems AB were commissioned to design a ventilation system for a newly built preschool in Linköping. Terms from the client was that it cost efficiency would cope with the energy demands that are placed on the building. The unit chosen was a cross-flow heat exchanger, and this work is to compare it with two other heat exchangers to see if a more energy and cost efficient could have been chosen. The heat exchangers that was chosen for the comparison was a rotating- and a counterflow heat exchanger. Simulations have been made to the different heat exchangers by the manufacturers.
Termomekanisk utmattning av Sanicro 25 : Materialmodellering med finita elementmetoden
The report aims to describe the austenitic stainless steel Sanicro 25 from a thermomechanical point of view. The thermal and mechanical properties of the material make it suitable for use in coal ? and thermal power plants. By the use of Sanicro 25 it would be possible to bring the efficiency of these plants up while bringing the carbon emissions down.A material model is created from material testing and validated through simulation in the finite element software Abaqus. The model that has been derived describes the material behavior during loading and stress relaxation for the first cycle in a thermomechanical fatigue test well.
Alternativa energikällor för varmvattenproduktion i fastigheten Galjonen. Solvärme och kylmaskinsåtervinning
Today more effective computer programs are in use, regarding design of geotechnicalconstructions. There is a risk that the theoretical background of the computerprograms, its limitations and the signification of the choice of soil parameter isforgotten when the computer programs become more user-friendly.This Master thesis deals with simulation and analysis regarding three computerprograms, FEM-design, with the addition Raft, Plaxis and BE-slab. Comparisons aremade for settlement and maximum moment in a concrete-plate. FEM-design is a threedimensional FEM-program, foremost created for design engineers. Plaxis is a twodimensional FEM-program, intended for geotechnical engineers while BE-Slab is aBoundary elements program in two dimensions that is mainly used by designengineers.
Effektiva logistiklösningar för import av vägsalt – Fallet Peab Sverige AB
Today more effective computer programs are in use, regarding design of geotechnicalconstructions. There is a risk that the theoretical background of the computerprograms, its limitations and the signification of the choice of soil parameter isforgotten when the computer programs become more user-friendly.This Master thesis deals with simulation and analysis regarding three computerprograms, FEM-design, with the addition Raft, Plaxis and BE-slab. Comparisons aremade for settlement and maximum moment in a concrete-plate. FEM-design is a threedimensional FEM-program, foremost created for design engineers. Plaxis is a twodimensional FEM-program, intended for geotechnical engineers while BE-Slab is aBoundary elements program in two dimensions that is mainly used by designengineers.
Att skapa lönsamhet i ombyggnadsprojekt: riskanalys, medverkan, organisering och målhantering
Today more effective computer programs are in use, regarding design of geotechnicalconstructions. There is a risk that the theoretical background of the computerprograms, its limitations and the signification of the choice of soil parameter isforgotten when the computer programs become more user-friendly.This Master thesis deals with simulation and analysis regarding three computerprograms, FEM-design, with the addition Raft, Plaxis and BE-slab. Comparisons aremade for settlement and maximum moment in a concrete-plate. FEM-design is a threedimensional FEM-program, foremost created for design engineers. Plaxis is a twodimensional FEM-program, intended for geotechnical engineers while BE-Slab is aBoundary elements program in two dimensions that is mainly used by designengineers.
Utveckling av lastmodell för Uppsala fjärrvärmenät
The aim of this study was to develop a load prognosis model for Uppsala district heating system to be used as a tool for heat production optimization. The methodwas to build three models for the different customer types; housing, industry andoffices and then scale them for the total system using data from Uppsala districtheating system. The heat load consists of two parts, one that is temperaturedependent and one that is dependent of the social behavior of the customers. Thetemperature part was modelled with an ARX model using an outdoor temperatureprognosis as input signal. The social behavior part was modelled using the mean ofthe social behavior from some days before and additionally by distinguishing betweenweekdays and weekends.
Kunskapsteori och kunskapsorganisation: En diskursanalys
This Masters thesis concerns epistemology in Knowledge Organization KO, as a field of study in Library and Information Science LIS. Using a theoretical model by Birger Hjørland and foucauldian discourse analysis as springboards, this study analyses three epistemological discourses in the practice of KO. The aim of the study is to show how these discourses are constituted and demarcated in relation to KO, as well as to examine how they fit into Hjørlands model. A brief historical outline of some epistemological trends in LIS is sketched, as well as examples of how different epistemological schools influence different parts of KO, e.g. information retrieval, indexing- and classification theory.
Modellering av reserv- och nödkraftsystem i JAS 39 Gripen
Simulation is a vital tool during development of JAS 39 Gripen, since money and time can be saved.The Auxiliary and Emergency Power System, AEPS, is a subsystem of the secondary power system in Gripen. It has the function of providing the aircraft with electrical and hydraulical power before activation and after deactivation of the main engine. The system also functions as backup in case of a safety critical problem in the main power supply system. The system basically consists of a control unit and an auxiliary gearbox. The gearbox is driven by an air turbine.
Metoder för prediktion av kardiovaskulär sjukdom med njurfunktionen
This study examines if the prediction of cardiovascular disease in hypertensive patients can be improved upon when renal function and microalbuminuria are added to the classical risk factors The predictive capability of a model is measured by discrimination, calibration, reclassification and Harrell's C.The results are ambigious. In most cases, microalbuminuria should be included in the model, but the results regarding the other measures of renal function are varied. Therefore, the selection of risk factors to include in the model depends on which measure of prediction one prioritizes..
Managementperspektiv på grisproduktion i Lojsta :
At the farm Fride, in Lojsta at the Southern part of Gotland, my family runs a pig production with 80 part-integrated sows in a ?Familybox-system?. The main parts of the facilities are from the early 90´s and have done their job. The production results have the last years decreased because of new infections so we have to do something before shifting ownership!
This degree thesis is meant to answer the question about which the optimal extension would
be today. By studying literature, use my own experience and make lots of calculations, I try to find out different opportunities.
Vilken är den teoretiskt optimala toppdiametern på bokmassaved vid motormanuell avverkning?
The bioenergy market has been introduced relatively late in a perspective of the Swedish forestry. Nowadays branches and tops are used more frequently as bioenergy after harvesting. Therefore, it has developed a competitive situation between pulpwood and bioenergy. This situation has even established some questions. Two examples of these are:
? At what top diameter should the final piece of pulpwood be crosscut to get the best economically result?
? Should the top diameter, at the final piece of pulpwood, be crosscut at a thicker or smaller diameter than what is done today?
The purpose of this report is to answer these two questions when the harvesting is made motor manually in beech stands.