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4105 Uppsatser om Calculation model - Sida 8 av 274
Barns tolkning av en modell för vattnets kretslopp : -förståelse och tillämpning
AbstractThe purpose of this study is to find out how pupils give expression of a water cycle model and if the model causes any misunderstanding. Two problems constitute the starting point for this investigation. The first question is: how do the pupils explain the water cycle with the help of the jar model (can of glass). The other question is: can the children see any similarities between the can of glass and our earth. Qualitative semi structured interviews with seven pupils in the ages of 8-9 have been used to show the pupils? own thoughts and how they express them.
Transferfunktionsmodeller modellering och prognoser av Sjötransportindex
We have by Statistics Sweden (SCB) been given the task of using different dynamic regression models in order to forecast service price index for sea transport. The aim is to see whether these models provide better forecasts than those previously used. This essay aim to identify, estimate and evaluate the selected prediction models. Through our data material we were given access to 28 sightings of sea transport index during the period of 2004 q1 to 2010 q4. We have chosen to evaluate three different transfer function models, one ARIMA model and one naive forecasting model. The input variables we decided to test in our transfer function models were the price of petroleum products, the port activity in Swedish ports and the lending rate of Swedish Central bank. The results of our study suggest that transfer function models generally provide better models than the ARIMA model and the naive forecast model.
Lönsam energieffektivisering : En beskrivning av energieffektiva åtgärder i flerbostadshus och dess lönsamhet
Environmental impact and management of energy is a highly topical issue in today's society. Climate impact must be reduced. The Government has set a target to reduce energy consumption in buildings by 20 % by 2020 and 50 % by 2050 compared to the energy use in 1995.With this in mind, we chose to examine how property owners can work on improving energy efficiency in existing apartment buildings. We also wanted to investigate profitability of different increasing energy efficiency measures and the calculation methods and the risk assessment performed by such investments. To tie in with government objectives, we also saw the possibilities of achieving these goals.20 companies were interviewed, of which 14 were property owners and 6 were consulting firms that works with energy efficiency.
VÄGTRAFIKBULLRETS INVERKAN PÅ UTFORMNINGEN AV BOSTADSBYGGNADER I STADSMILJÖ
The public interest in central living in today?s cities has led to an increasing effect of traffic noise pollution, and today 20% of the inhabitants in Sweden suffer from noise a level that exceeds the limits. At the same time the traffic keeps increasing, and recent researches shows that traffic noise pollution and several of today?s most common health issues are connected, for example, reduction of performance, sleeping issues and cardiovascular diseases. For this cause rules, guidelines and environmental goals has been developed, as well as software?s which calculates the levels of pollution, all this to investigate and improve the environment.
Latent värmelagring i vattenburet uppvärmningssystem med elpanna för byggnadsapplikationer
Latent heat storage is a way to store thermal energy when a phase change material undergoes a phase change. The advantage of latent heat storage is the capability to store more energy per mass unit than other heat storage methods. The most commonly used phase change in latent heat storage is the transition between solid and liquid. Phase change materials can be divided into organics, inorganics and eutectics.In the Nordic electricity market the price of electricity is set every hour by Nordpool spot, which leads to price fluctuations because of changes in demand. The main goal of this report is to create a latent heat storage system in a single-family home and investigate the possibility to save money by charging the latent heat storage system when the price of electricity is low, and discharge when the price is high.The thermodynamic model consisted of a ?tube-in-tube? heat exchanger with phase change material in the outer tube and water as the heat transfer fluid in the inner tube.
Parametriserad modell av motorprototyp med Solidworks
The purpose of this thesis has been to build a parameterized model of a prototype motor in the program Solidworks, to use in future optimization of aspects of effectiveness and weight. The result were two models. The first model were one minor part of the whole design in 2D, to be able to optimize and study the minor part with a faster loss simulation. The second model was the whole design in 3D. The whole model were done with the three programs Solidworks, Comsol and Matlab.
Prefabricerade Passivhus
European Union has made a new decision that all new built houses by 2020 shallbe near-zero energy houses. Boverket?s definition of near-zero energy housesintends buildings with good energy performance in which a proportion of theamount of energy that must be added to the building is made of renewable energy.Passive House is a set of requirements from FEBY designed to build energyefficient buildings. This is achieved by reducing loss of heat through the buildingenvelope and to take advantage of the passive heat from solar radiation,installation and heat sources like people living in the house.This project has been made with help of Anebyhus and one of their model houseshave been examined from the report?s issues, including Anebyhus?s energyperformance, requirements for the manufacturing and assembly, how theenvelope must be improved to fulfill the requirements for the Passive House andwhat energy calculation programs are available on the market.The report aims to provide solutions for energy efficient houses that are adaptedfor production of house building.Two visits to Anebyhus has been done to study their manufacture and assemblyof building elements.
Kommunernas dolda pensionsskuld
Background: In 1998 it was stated that Swedish municipalities would report the pension liabilities according to the mixed model where the pension liabilities before 1998 was moved from the balance sheet. The mixed model has been criticized by economists for not showing the total pension liabilities. To remove some of the liabilities in the municipalities balance sheets means that the solvency improves. Some municipalities have decided to go against the municipal accounting law and recognize all of the pension liability as a liability according to the full funding model. When two accounting models are being used the comparison of the municipalities' financial statements is much harder.Purpose: The main purpose of this study was to study the reason why some municipalities apply full funding model rather than the mixed model.
SCA Skogs arbetsmetoder för att fastställa nyttan av en väginvestering
The basis of road investments is to minimize the transportation cost. The forest industry wants roundwood to be available during the whole year. One way of determine which road to invest in is to do a cost/benefit calculation.
SCA Forest lacks a uniform approach to determine the utility of a road investment. The goal of this report is to describe how the organization works today and find areas of improvement.
The data collection was done through interviews.
Används ekonomiska planeringshjälpmedel i lantbruksföretag : beslutsunderlag med hjälp av kalkylmetoder
In agricultural educations you learn to use different economic planning tools, as basis for decision. The purpose and goal of this work has been to find out if economic planning tools are used by the farmers in Sweden. We choose to do an investigation through personal interviews, and used an inquiry to get as equivalent answers as possible from the farmers.
This work contains a literature study with relevant facts about the questions that is brought up in the inquiry. This study of literature explains shortly some different calculation methods and bases for decision. It also contains useable information that is important to know before an investment.
The questions that are asked to the farmers have focused on the use of calculation methods and economical planning tools.
Analysmodellen - en variation i tillämpningen?
The purpose of our essay is to examine if variation exists in the way that auditors try their independence, this so called analysis-model. We will suggest some factors that influence the way auditors practise the analysis-model. The institutional theory predicts no differencies since the normative pressure could be expected to be severe. But we found that among other things people?s qualifications, personalities and audit firm?s size and age influence the way auditors try their independence.
Icke-linjära modelleringsteknikerav förspänd betongkonstruktion : Reaktorinneslutningen på Forsmark 3
A new material model, for the FE-program ADINA, has been verified against twoexperiments. One unreinforced concrete beam and one reinforced concrete beam.The model, DF-concrete, has the possibility to estimate true concrete. However theresults indicate that in order to be sure that the estimations are true, there ought tobe data from the true concrete to verify against.Two FE-models have simulated the behavior of a ring-shaped part of the nuclearcontainment vessel. The results from the first, frictionless, model agree with similarsimulations and hand calculations for high pressures in the containment vessel. Thesimulations of the nuclear containment vessel show cracking in the concrete after10-11 bars of over pressurization.
En geopolitisk återkomst : Kultur, ekonomi och territoriell konstruktion i samband med inomstatliga konflikter
Through geopolitical theory this thesis explores how conflicts within states can be read and understood according to an analytical model determining one or several possible causes for the conflict. The model is created by the author and reflects geopolitical theory by giving three possible explanations to an intrastate conflict: culture, economy or territorial construction. The aim of the thesis is testing this model on two selectively chosen case studies ? i.e. two intrastate conflicts ? namely: the upcoming referendum in Scotland and the terror attack at Tiananmen Square in China.
Hur fungerar logistiken i produktionen på ett byggföretag?
The Work has been performed to, and in cooperation with Vetlanda Energi och teknik AB.District heating for commercial purpose started in the USA in 1877. Today the network has grown into big and complex systems, which demand maintenance and service to keep up the security of the delivery. When a district heating network expand, it becomes difficult to perform reliable calculations. For this purposes there are a few suppliers who design and deliver systems for documentation and calculation of district heating networks.Vetlanda Energi och Teknik AB is in the position where they must get a system for documentation and calculation for district heating, and therefore they need a basis to get a system. The target is to write a requirement specification that will follow the basis.The Swedish market has been inventoried, and suitable systems have been selected.
Osäkerheter vid brandteknisk dimensionering av ventilationssystem
This masters thesis deals with smoke spread via ventilation systems. One aim of the thesis is to investigate and explain the differences in efforts to prevent smoke spread via ventilation systems in different countries. A second aim of this thesis is to investigate how frequently occurring smoke spread via ventilation systems in Swedish buildings are. A third aim is to investigate how uncertainties in input variables to smoke spread calculations will affect the result of calculation. To be able to do this the most important input variables are identified and analysed.