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713 Uppsatser om Dynamic simulations - Sida 22 av 48

Utvärdering av en beslutsåterkopplad kanalestimator för tredje generationens mobiltelefonisystem

This Masters thesis work describes a comparison between two different methods for estimation of the down channel (base station to mobile subscriber) in Wide-band Code Division Multiple Access (WCDMA). The first estimation method, Optimal Feed-forward Channel Estimation (OFCE), is a conventional method that bases the estimates on data that is known to both sender and receiver, so called pilots. The second method, Decision Directed Channel Estimation (DDCE), is an elaboration of OFCE. It also uses user data for estimation. Simulations show that DDCE, in comparison to OFCE, does not attain an improvement in signal-to-noise-ratio (SNR) for high bit error rates (BER).

Avbördningskapacitet för Traryd kraftverk: en modellstudie vid dimensionerande flöde

Sydkraft Vattenkraft AB owns and operates the Traryd hydropower plant, located in the river Lagan in the southern part of Sweden. The gravity dam is classed according to RIDAS guidelines (Hydropower Industry Dam Safety Guidelines) as a class 1B dam. This means that the dam must discharge a class 1-flow which has a return period of 10 000 years. The inflow into the dam has been calculated in an earlier report to 495 m3/s, with a waterline at an elevation of 126, 3 meters above sea level. The gravity dam has a discharge system with two rectangular weirs, which results in a smaller discharge than the necessary 495 m3/s.

Energieffektiviserande åtgärderpå Robertsfors VA-nät : En förstudie av vilka energieffektiviserande åtgärdersom kan göras på pumpstationer och reningsverk

The objective of this work was to introduce measures to reduce energy and water demand at Gävle Söder 17:10. To succeed, this energy audit has been made. The work is based on collected statistics from the property owner Norrporten, measurements, literature review and through consultation with experts in the field. Two models, one for each building, have been created in the simulation program BV2 to estimate the potential of energy measures based on the collected information. The models in BV2 have been verified against the statistics of the energy consumption.With the help of calculations and simulations, seven cost-effective measures have been identified.

Utvärdering av tillgänglighet på Stora Ensos massabruk i Skutskär

Self-driving cars are soon to become a reality to the commercial market. A self-driving car does not have a human operator, which enables some interesting characteristics. The main benefits are considered to be:The number of accidents and traffic jams should be reduced.Enhanced comfort.Energy usage could be decreased while capacity could be increased.This study concerns the causes for improved energy efficiency. The reason for improved energy efficiency is mainly because of the variation in terms of acceleration, braking and distance holding are reduced. The vehicles are more intelligent and can work together as a unity.

Analys av mellanspänningsnätet i centrala delar av Västerås stad

The dependency of continuous electricity supply is high in the Swedish society today, at the same time no one is willing to pay for a too costly or over dimensioned power distribution system. The owners of the distribution systems are the ones responsible for this balance act of maintaining a high quality of electricity delivery to customers at a reasonable cost.In this master thesis a limited part of the primary distribution system (10 kV), owned by Mälarenergi Elnät AB and located in the city centre of Västerås, was chosen for a deeper analysis of its reliability. Its ability to handle outages of system components (N-1 and N-2 contingency analysis) was investigated to find out potential weak spots and parts of the grid that showed signs of being overdimensioned.The results of the performed simulations showed that in 74 % of the studied N-1 contingencies cases, consisting of outages of a bus bar in a distribution substation, the system could handle this without causing outages in other parts of the grid. For the N-2 contingencies 61 % passed the test. It was also found that one of the two included high voltage substations could alone supply the investigated part of the grid.

Konstruktion och utformning av skydd till spolverk

This thesis has been carried out in cooperation with Burseryds Bruk AB.Burseryds Bruk is a company that manufactures steel strapping. The thesis isabout developing a concept of protection that should be used to protect theoperators from the rotating parts of the machinery lines. The aim of the projectwas to improve work safety for operators working at the machines by producing aconcept for a protective device. The project's first part was based on ergonomic data collection methods tounderstand the operations performed on the machine and the hazard occurringduring the process. The methods used to collect data were, interviews,observations and questionnaires with the operators of the company. This was thenused to make the ergonomic analyzes hierarchical task analysis and link analysis. The data collected from the company's operators was used create 10 conceptswhich were then evaluated.

Analog-to-Digital Converter Design for Non-Uniform Quantization

The thesis demonstrates a low-cost, low-bandwidth and low-resolution Analog-to- Digital Converter(ADC) in 0.35 um CMOS Process. A second-order Sigma-Delta modulator is used as the basis of the A/D Converter. A Semi-Uniform quantizer is used with the modulator to take advantage of input distributions that are dominated by smaller-amplitude signals e.g. Audio, Voice and Image-sensor signals. A Single-bit feedback topology is used with a multi-bit quantizer in the modulator.

Utvärdering av en beslutsåterkopplad kanalestimator för tredje generationens mobiltelefonisystem

This Masters thesis work describes a comparison between two different methods for estimation of the down channel (base station to mobile subscriber) in Wide-band Code Division Multiple Access (WCDMA). The first estimation method, Optimal Feed-forward Channel Estimation (OFCE), is a conventional method that bases the estimates on data that is known to both sender and receiver, so called pilots. The second method, Decision Directed Channel Estimation (DDCE), is an elaboration of OFCE. It also uses user data for estimation. Simulations show that DDCE, in comparison to OFCE, does not attain an improvement in signal-to-noise-ratio (SNR) for high bit error rates (BER). An improvement is only seen when the BER becomes much lower than what is common in real situations. In conclusion DDCE is complicated, involves many mathematical operations and gives insignificant improvement of SNR when BER takes common values. It is legitimate to question if it is possible to use the method in a real mobile phone system..

GPIB- kommunikation och PID reglering med LabVIEW

LabVIEW ger en snabb och enkel tillgång till att styra instrument och en mycket stor databas med drivrutiner för DAQ-kort och olika datorgränssnitt (GPIB, serie, osv.).Många instrument och datorer kan anslutas till GPIB-bussen.  Detta kan ge en praktisk modell för utveckling av instrumentets styrprogram i LabVIEW med hjälp av GPIB-gränssnittet.Ett program i LabVIEW 8.2 med hjälp av GPIB-bussen kan kopplas till t.ex. multimetern (HP-34401A) för att mäta och visa multimeters noggrannhet. Men på grund av fel i drivrutiner för GPIB-gränssnittet kunde jag inte köra programmet med GPIB-bussen.Genom att använda LabVIEW 8.2 med hjälp av DAQ-kort kan en PID-regleringsalgoritm simuleras. PID konstrueras med virtuella instrument som innehåller alla nödvändiga komponenter och utrustning som krävs för att reglera någon linjär eller olinjär process exempelvis att nivåreglera två tankar i serie.

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.

Bärande betongkonstruktioner i miljonprogrammets flerbostadshus

LabVIEW ger en snabb och enkel tillgång till att styra instrument och en mycket stor databas med drivrutiner för DAQ-kort och olika datorgränssnitt (GPIB, serie, osv.).Många instrument och datorer kan anslutas till GPIB-bussen.  Detta kan ge en praktisk modell för utveckling av instrumentets styrprogram i LabVIEW med hjälp av GPIB-gränssnittet.Ett program i LabVIEW 8.2 med hjälp av GPIB-bussen kan kopplas till t.ex. multimetern (HP-34401A) för att mäta och visa multimeters noggrannhet. Men på grund av fel i drivrutiner för GPIB-gränssnittet kunde jag inte köra programmet med GPIB-bussen.Genom att använda LabVIEW 8.2 med hjälp av DAQ-kort kan en PID-regleringsalgoritm simuleras. PID konstrueras med virtuella instrument som innehåller alla nödvändiga komponenter och utrustning som krävs för att reglera någon linjär eller olinjär process exempelvis att nivåreglera två tankar i serie.

Analys och implementation av EPIServer

This report describes how we, with support from SYSteam Datakonsult AB Värnamobuilds a dynamic website for a fictional company. The purpose of this work is to tietogether our studies with the businesses in the region, and expand our knowledge.Together with Peter Bäckrud from SYSteam we worked out the goals to achieve thispurpose. The goals are to create a polished intranet to a company with the webpagepublishing tool EPIserverThis report begins with describing the goals and visions that were set up. Then follows athorough theoretical background that describes the areas we have touched, to give thereader an idea about the work. The report then moves into the creation phase that talksabout the problem that occurred during development.The creation phase is split up into two parts where the first part gives a good descriptionabout how we designed a usability friendly website that would fulfill the goals we had setup.

Design och implementering av styrlagar för generisk flygplansmodell

For research purposes Saab has developed a generic mathematical model denoted VEGAS of an aircraft with a configuration similar to JAS 39 Gripen. Today parts of Gripen backup control system are used also for VEGAS making the system subject to both corporate and defense secrecy. The main objective of this master thesis is to design, verify and implement public pitch axis flight control system for VEGAS. Furthermore, simplifications regarding the design process is to be examined. Design of pitch axis flight control system for the entire flight envelope has been carried out.

Att främja social hållbarhet i gröna miljöer : En fallstudie av ett projekt i Upplands Väsby

AbstractIn my study I have investigated how a constructed outdoor green environment can beused, managed and how it works. The study also investigates the concept of socialsustainability, where, for example, civil dialogue is a method to promote this. Thisinvestigation mainly gives account for the inhabitants viewpoint but also a gardenersperspective. The study focuses on the planning process of the study object, what theoutcome has been and how the users of the green environment, think about the result. Inthe process there has been a strong concern of involving the residents and others usingthe area.

Användarorienterad design av anestesisystem

In inhalation anesthesia life-support systems are used to provide gases to the patient and to monitor important parameters. These systems are used in dynamic and stressful situations where the information-load on the operators often is significant. This thesis presents a design concept of an anesthetic system. The design goal has been to keep the information-load on the operator low with the objective to minimize confusion and error.A number of contextual inquiries were made in the operating room during surgery at four hospitals in Sweden. The goal was to understand the actual use-situations when anesthetic systems are employed.

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