Sökresultat:
4105 Uppsatser om Calculation model - Sida 5 av 274
Automatisk mätning och detektering av röjande signaler
This master thesis has been performed at Sectra Communications AB in Linköping where they manufacture electronic encryption devices. In cryptology it is essential that an eavesdropper cannot find the plain text. To assure that a system is safe, all devices are thoroughly examined so that they don?t emit any secret information, so called Compromising Emanations (CE). This is done by comparing the secret signal with measured signals on the screen of an oscilloscope, a process that is very time consuming and furthermore, the risk of missing compromising emanations is high.
Klimatpåverkan vid vägbyggnad -beroende av vald konstruktion
It?s a fact that the climate is affected by the vehicle that runs on the worlds roads. But theconstruction of the road itself is rarely thought of as a climate threat. Svevia and the Swedish roadadministration have opposite views of how the construction of roads should be carried thru. It?sthe difference between those two construction methods that is the base in our thesis.The amount of energy use or the emissions are not analyzed for neither the Swedish roadadministrations nor Svevias construction models.
Hållbarhetscertifiering av stadsdelar : En studie av BREEAM Communities praktiska tillämpning i svensk stadsbyggnad
In this diploma work the approach of determining the required amount of reinforcement in slabs exposed to pure tension is processed, on behalf of Ramböll Uppsala. It is a well-known problem in the industry that there are uncertainties in the determining of the amount of crack reinforcement, especially for structures exposed to pure tension. Cracking caused during the time of dehydration in concrete slabs is the most common defect according to statistics made by CBI[1], which provides numbers as high as 35 % of all the defects caused on slabs are generated by cracks. Comparisons between Sweden's former national standard BBK 04, Building Regulations for concrete structures due to restrained forces of shrinkage, and the current European standard Eurocode 2 are carried out through theoretical studies and concludes with several examples of calculations. Rigorous calculations of both standards, BBK 04 and Eurocode 2 with application of the national annex in Sweden and Denmark are performed.
Demonstrationsprojektets roll i framväxten av ny teknik: Fallstudier av två vindkraftprojekt
This report describes a synchronous machine model with magnetic saturation in d-axis, neutralconnection and electrical exciter interface for the transient simulator PSCAD/EMTDC. It hasbeen designed and verified in comparison to the regular machine model in EMTDC.The performance of the model is very good when incorporating a linear as well as a saturatedmagnetising inductance. The dynamic deviation is only thousandths to ten thousandths perunit. By using a cubic interpolation of the saturation curve, the model gives a good representationof the saturation effect. The open source code implementation of the synchronousmachine model gives the possibility to easily adapt the model to specific requirements.The derived model makes it possible to simulate a synchronous machine with its excitationsystems, e.g.
FEM i praktiken : En studie i FEM-Designs användningsområden inom konstruktionsprojektering
This diploma work has been conducted for the consulting company Ramböll inUppsala, Sweden with the purpose to perform a study with the calculation programFEM Design 9.0 made by Strusoft. The aim has been to find out if it is possible to gainadvantage by utilizing more advanced 3D software for design calculations, instead ofthe traditional methods currently used in construction works.The method of approach has been to model an existing warehouse building with theprogram FEM Design, and then compare the results with those attained with FrameAnalysis and hand calculations. These results are then analyzed. An evaluation is maderegarding to what benefits can be achieved using a more advanced 3D-model.The results of the study show that the differences between the methods are not ofany significance with regard to the design of the steel frame. However in morecomplex materials such as reinforced concrete, the differences become more notable.The conclusions drawn by the authors of this study into FEM Design are that theeducation requirements of the program are higher than for simpler programs, whosepurpose are solving predetermined problems.
Modellering av en panna med rörlig rost :
The aim of this master thesis was to create a dynamic model for the processes in a solid fuel boiler of the moving grate type. Another aim with the model was to keep it as simple as possible but still able to catch the dynamics of the processes in the bedplate of the boiler. The creation of the model had its origin from drying and combustion equations used in earlier modeling work of boilers. The represented model has been used to simulate different kinds of disturbances in a boiler and different ways to control the boiler. These tests show that controlling a number of parameters in the bed of the boiler is an effective way to keep the grate stable during disturbances.
Adaptiv katalysatormodell för reglering
This master?s thesis describes the development of a model of the catalystsystem aiming at control by an MPC. A well functioning model, which is suitable in control purpose, is important while emission legislation become more and more hard to fulfill for the car manufacturers. Much research has been done in the field of physical modeling of the system, but in this work a linear adaptive time discrete ARX-model is developed and validated.The systems tendency to change its dynamic during usage implies that the model must be adaptive. The developed model proved to be well functioning and shows promising conditions for the MPC design.
Simulering av simulinkmodeller medExtended Kalman FilterTidsoptimering av integrering
Simulation of different systems can be done using a graphical model description of the system based on block diagrams. The simulation software Matlab/Simulink offers a lot of possibilities to describe a huge number of systems, which can be linear as well as nonlinear. The simulation using Matlab/Simulink is done by integration based on different kinds of numerical methods.When nonlinear Simulink-models are simulated, it is often interesting to apply a Kalman filter to handle the noise that may occur within the process as well as corrupting the measurement. However, application of such a filter leads to an extensive time-consumption despite using fast computers. The reason is that the existing Matlab functions are not constructed for time optimal evaluation.
Modell av en synkronmaskin för PSCAD/EMTDC med magnetisk mättning i d-led och elektriskt gränssnitt för fältmatare
This report describes a synchronous machine model with magnetic saturation in d-axis, neutralconnection and electrical exciter interface for the transient simulator PSCAD/EMTDC. It hasbeen designed and verified in comparison to the regular machine model in EMTDC.The performance of the model is very good when incorporating a linear as well as a saturatedmagnetising inductance. The dynamic deviation is only thousandths to ten thousandths perunit. By using a cubic interpolation of the saturation curve, the model gives a good representationof the saturation effect. The open source code implementation of the synchronousmachine model gives the possibility to easily adapt the model to specific requirements.The derived model makes it possible to simulate a synchronous machine with its excitationsystems, e.g.
Analys, modellering och återskapande av fordonsdynamiska rörelser i tåg
The purpose of this thesis was to analyse, model and finally generate dynamic vehicular motions in a train. The objective with the analysis was to find important motions for a realistic train experience. The motions from the analysis were then weighted against possibilities for generation in a motion platform.A dynamic motion model was created to model the selected motions. The model was implemented in a simulation environment, more specifically MATLAB/Simulink. The simulation environment was used to simulate the model and to generate outputs to control a motion platform.
Kalkylarbete för byggnadsprojekt med Vico Office : För- och nackdelar med 5D BIM
AbstractBuilding Information Model/Modeling/Management (BIM) is a tool that allows for efficient working methods. BIM saves time and money while providing the potential for visualization. This method of working is based on a 3D-model, and then a fourth and fifth dimension are connected. 5D modeling means that a spreadsheet creates cost estimates based on the 3D model. This provides opportunities to carry out calculations in the early stages of the projects. Calculations are currently performed manually and do not contribute to the development that the construction industry requires.
Pricing Credit Default Index Swaptions A numerical evaluation of pricing models
This study examines the background and nature of the credit default index swaption (CDIS) and presentsrelevant methods for modelling credit risk. A CDIS is a credit derivative contract that gives the buyerright to enter into a credit default index swap (CDS index) contract at a given point in time. ACDS index, in turn, is a multi-name credit default swap (CDS). Within the eld of research, thisthesis identi es the CDIS pricing models presented by Jackson (2005), Rutkowski & Armstrong (2009)and Morini & Brigo (2011) as the most recognized and developed. These models are evaluated byreconstruction in a numerical software environment.
?Vad är det jag gör egentligen?? - om att med videons hjälp bli medveten om helheten
This project consists of an adaptation, trial and evaluation of a model for practicing. Based on prior research I created a model aiming mainly to raise a musician?s self- awareness around the different parameters a performance consists of. An additional wish was for it to simultaneously assist the musician in monitoring his or her progress. With video recording and self-evaluation as the two main parts I tried the model by using it over a period of three months.
Multipel regressionsanalys av variabler som paverkar BNP
In this report a model was constructed in order to determine how a number of covariates influence the gross domestic product, GDP. The covariates were chosen depending on their expected influence on GDP, for example education and life expectancy. The data used in this report are collected from the World Bank. The model to describe GDP has been calculated using multiple line arregression. In order to reach a reliable final model the number of covariates has been gradually decreased to eliminate insignificant covariates.
Identifiering av områden med risk för fosforförluster genom ytavrinning : metodutveckling med GIS
The eutrophication of lakes and seas with the algal bloom and deficiency inoxygen that follow, has been given priority by the Swedish government as oneof 16 environmental objectives. The purpose of this project was to develop a toolbased on a simple model, limited amount of data and geographic informationsystem (GIS) to identify areas with risk for phosphorus losses due to surfacerunoff. This tool can act as a decision support to decide where appropriatemeasures should be applied with the aim of reducing phosphorus losses and bythat the eutrophication.The method that has been used is a combination of two models, one calculatingthe potential erosion while the other one identifies areas of erosion (net erosion)or deposition. This ability is of great importance because potential erosionshould be calculated on areas with net erosion. Areas with high potential erosionhave an increased risk for phosphorus losses due to surface runoff.The potential erosion was calculated based on factors which describe how topography(LS), land use (C), soil type (K) and precipitation (R) effect the erosion.All of them have been modified to a greater or lesser extent.