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725 Uppsatser om Constructional calculations - Sida 6 av 49
Hantering av småskalig elproduktion : Utveckling av modell för dokumentation och elkvalitetsberäkningar
The interest in small-scale electricity in Sweden has increased strongly in recent years. The interest is noticeable both among politicians to increase the share of renewables in the energy mix, and among electricity consumers to partially replace purchased electricity with self-produced. This has resulted in a significant increase of electricity production in low voltage grids in recent years, and the trend appears to continue in the coming years. The majority of the new production plants are solar cells, followed by wind turbines, and it is also in these the greatest efforts are made in this paper.Distributed generation is often seen as something positive since it will contribute to reduced transmission losses and reduced voltage drop in the networks, and that it increases the share of electricity from renewable sources. In cases where the grids are not strong enough, or in other ways not adapted to manage the installed production, power quality may be adversely affected.
Energiförbrukning för putsade, odränerade träregelväggar i fuktigt respektive torrt tillstånd
In recent years, moisture damages have been noticed in rendered, undrained stud walls. The design is built on the principle one-stage tightening which means that there is no air gap in the construction. The damages have occurred when water has permeated through the rendering in leaking connections and fittings for windows, doors, canopies, balconies, terraces and awnings. Behind the plaster carrier, which consists of either polystyrene or rigid mineral wool, plasterboard has often been used as a wind protection barrier. In many cases the wind protection barrier and the underlying wooden studs have been exposed to mould and in some cases even rot.
Jordtäckta hus : Energiberäkningar och kostnadskalkyler på ett jordtäckt hus i Malmö
With rising energy prices and the threat of climate change, energy costs and energy savings havebecome a central and important part in building. Therefore it is interesting to explore different andnon-conventional methods of energy conservation. Building Earth sheltered houses is such a method.Earth provides good insulation and provides the ability to both reduce the total heating needs and toreduce the maximum power demand. The aim of this study was to construct a house in Malmö and seeif Earth sheltered houses can be a cost effective alternative for the construction of sustainable andenergy-efficient houses.Previous studies have shown that Earth sheltered houses have reduced their power requirement with upto 25% and their use of energy with 10%. Numerical calculations in Comsol Multiphysic 4.2, wasperformed on a house with different degrees of earth covering.
Analys av verkningsgrad för en industriell DC-DC omvandlare
This thesis is performed in collaboration with Kraftpowercon AB in Surte, Sweden. Focus has been on to identify the powerlosses in one of Kraftpowercons halfbridge DC-DC converters. First theoretical calculations are made, the calculations is verified with measurements of six different operation modes. In a later stage, methods like soft switching and synchronous rectifying are proposed to increase the efficiency for the converter. To achieve softswitching for the halfbridge, the LLC resonant converter topologies are implemented and examined.
Skalning och brusberäkning av tvåportsadaptorer
The goal of this work is to summarize the calculations for scaling and noise of twoportadaptor. Two different methods has been described and used for the final results..
Möjliga tillämpningar av BIM vid miljöcertifieringsarbete
In the construction industry today there is a significant technological revolution goingon. New methods for automated processes and information management are developedcontinuously. Intense studies are currently taking place to ensure ways and means toembrace the new technology of BIM.At the present, environmental certification systems are considered cumbersome andchallenging. However, the increasing demands of sustainable development in the constructionindustry imply that the environmental certifications will not disappear. ThisMaster Thesis examines the possibilities to apply BIM technology within the field ofenvironmental certifications to streamline the processes.The applications that provide the best opportunities are:- To use BIM to be able to, during the design stage, dynamically evaluate the resultor score a certain building will achieve.- To avoid unnecessary work through collection of data for calculations directlyfrom a BIM-model.- To be able to automate certain time consuming calculations that are currentlyperformed manually.- To automatically examine the completed model to ensure that the demands arefulfilled.The possibilities to use BIM within these areas are however limited by the technologyitself.
Torkning av flis med restvärme : Metoder för att sänka återledningstemperaturen
The purpose of this study has been to evaluate whether a Low temperature bio-mass dryer could be integrated with the local district heating system in Malå. The aim is to increase the thermal efficiency of the cogeneration plant in Malå, by lowering the temperature of the cooling medium. Another benefit that comes from this is improved combustion efficiency at the power plant, since drying the fuel causes an Increase of the heating value.Simulations has been made in Excel, and with use of linear regression, to find out if it is profitable. Data for this purpose has been supplied by the power company Skellefteåkraft and furthermore SMHI.The result of the Calculations shows that a very efficient bio-mass dryer is needed, if yield of investments should be made possible. An Investment of 4,27 Mkr, in a dryer, could at a such criterium return 60000 kr/year, if the price of the biomass is 190kr/MWh.
Spårtaxisystem i Uppsala
An increased awareness about the global warming has created a demand for more information on how the climate is affected by different activities.This master thesis was initiated by Tricorona, a Swedish company that offers its customers analysis and calculation of their climate impact. Tricorona also supplies climate neutralisation with CERs, in accordance with the Kyoto protocol and controlled by the UN. This work demands updated emission factors for greenhouse gases. An emission factor gives information about the greenhouse gasintensity of a service or a product [kg CO2-eq./ functional unit].The purpose of this thesis is to examine how electricity, district heating, hotels, taxis, food and materials affect the climate and how emission factors for these areas can be calculated.This was done by reviewing and comparing different studies and by interviewing experts. The information was evaluated and recommendations on calculations and emission factors were made.The consumption of energy is the main source of greenhouse gas emissions for district heating, electricity, hotels, taxis and materials.
Reviderade räkenskapers betydelse för bankers kreditgivningsprocess?
In 1983 Sweden passed a law stating that all limited liability companies are to be included into a mandatory auditing system. According to the EEC, courts fourth amendment, each country has the right to decide whether to exclude a mandatory auditing system for smaller companies. Audit reports in Sweden are considered to be very important for the bank crediting system. Should this be eliminated, it would be more difficult for banks to trust an audit. The significance of calculated audits is questioned in regards to the banks accrediting system.
Maskinduglighet på planlaserskärare
Lars Höglund AB is one of Scandinavia?s most qualified manufacturers of sheet metal products and provides custom designed products of very detailed precision. One of the main methods of manufacturing is laser cutting. When Lars Höglund AB signed up a new customer, with high demands in tolerances for the products, Lars Höglund AB thought it would be necessary to know the capability of the laser cutting machine. Also the process of how to retrieve this capability was interesting. The capability will be researched for the following elements: Cutting right angles in squares with a corner radius of 1 mmCutting corners which are not right angleCutting of circles with constant radius Measurements were made on 150 pieces of sheet metal details, which had been cut out by the machine. The data from the measurements where later used to study the capability.
Arbetsmiljöekonomisk utvärdering av ergonomiförbättringar : Grundade i antaganden om sjukfrånvaro och förändring i arbetsbelastning efter intervention inom en avdelning i läkemedelsbranschen
The purpose of this study is to incrementally, through a combination of various methods, examine the assumptions about the working economic outcomes that can be made based on planned ergonomic intervention in a department at Pfizer Health AB in Strängnäs. The study contributes to knowledge about how assumptions on OSH financial results can be made, based on planned ergonomic interventions. These assumptions were based on biomechanical calculations made on the basis of ergonomics measurements with inclinometer. The study is important because previous research has shown that poor work environment have a bad impact on the economy of a company in different ways. It can for example be negative impact on the company's productivity and quality of the units produced or the services provided.
Verktyg för hjulbyte
Purpose of the thesis is to construct a tool for car wheel change. Car wheels can be heavy and hard to handle and therefore the company Movomech intends to develop a tool that makes wheel change easier. Movomech does not have any similar product and because of this the work was condition less.The intended users of the product is tire workshops and there for the work began with investigation of these. The reason of the investigation was to see how wheel change is done and how tire workshops are planed. The tire workshops? crew?s opinions were also considered and above all one important conclusion was made.
Analys av off-design prestanda för ett absorptionskylsystem
This master thesis project at KTH is performed in the Mechanical and Aerospace Engineeringdepartment at University of Florida (UF). The thesis is a small part of a gas turbine researchproject where a vapour absorption refrigeration system (VARS) and a high pressure regenerativeturbine engine (HPRTE) are integrated together. The main objective is to build a computermodel of the VARS. The computer model is supposed to be used to analyse the off-designperformance of the VARS and should also be easy to integrate as a subroutine in a more complexsystem model. To model the VARS some knowledge of the absorbent/refrigerant mixture had tobe well known, in this case a mixture of ammonia and water.
SAMVERKAN STÅL/BETONG : Kontroll av kapacitet hos blockankare i Connector Samverkansbalk
In April 2007 we contacted Lennart Augustsson at Designpartners AB in Västerås. He came up with the idea to investigate and evaluate their construction of a interaction beam, CSB-beam. CSB is short for Connector Interaction beam. The beam is based on a horizontal C-profile of high-tensile steel and in the bottom of the profile are vertical flat bar welded so called block connectors. These block anchorsare also made of hightensilesteel.
Uppvämningssystem med biobränsle : en fallstudie på Malmviks gård
The use of bio fuel is increasing every year. Nowadays you will find different alternatives to oil and electricity heating system. In this essay I have examined what the economic conditions are to invest in a bio fuel furnace. I have chosen to assume from a specific farm and do a case study on this farm. Malmvik farm is located just outside of Stockholm.