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11955 Uppsatser om Viable System Model - Sida 3 av 797
Ett flervariabelt feldetekteringssystem för övervakning av bärlagertemperaturen i vattenkraftturbiner
The purpose of this thesis work was to develop an automatic fault detection system for surveillance of bearing temperature in hydropower turbines. The parameters used except the bearing temperature were cooling water temperature and cooling water flow. A simple static model based on data sampled every minute was developed to estimate the bearing temperature. Then a detector for detection of change in bearing temperature based on the CUSUM-algorithm was designed. Since the amount of data was very small the developed model was too uncertain to be used in a working system.The designed fault detection system showed to work well for the available data.
Metodikmodell för styrning vid inköp
The work with this report has been focused on developing a methodology model for control at purchase. The methodology model covers parts classification, dispatching systems, batch shaping and more. The aim with the methodology model is that it will be used as an aid for a cost effective material planning to increase the value for customer.The work covers also a description of the present situation and the purchase process at Company X. Six parts have been applied, two from each class (A, B and C), in the methodology/model. The parts that have been applied are included in the flow between Company X and their supplier Company Y.Data have been collected trough literature studies, interviews and the company?s business system.
Utveckling av en dynamisk Simuleringsmodell av en skotare
The predominant forestry harvesting method is based on the harvester-forwarder method, theharvester folds, branches and cuts trees, and sorts the logs into piles, while a forwarder transportsthe logs to a landing area.This master thesis work is about realization of a dynamic forwarder simulation model, and itspurpose is to provide an integrated forwarder simulation model in MATLAB/SimMechanicswhere the forwarder is based on a concept using pendulum arms to connect wheels and chassis.Active suspension control is developed and implemented into the simulation model, and finallycompared in simulation with passive suspension.In a first step, an integrated forwarder simulation model is developed, containing a simplifiedforwarder model, a tire-to-ground interaction model and a test track model. The simplifiedforwarder model is based a rigid multi-body system with a spring-damper suspension of thependulum arms. The tire-to-ground interaction model calculates the reaction forces, friction fromthe ground and applies the propulsion force. The test track model is a simplified version of thereal test track in Skogforsk. The propulsion wheel torque control is used to regulate theforwarder speed.
Optimering av ett småskaligtvattenkraftsystem
This master thesis covers the seasonal planning of a small scale hydropower system. The system in this study is owned and operated by Mälarenergi Vattenkraft AB. The total system consists of 4 different main rivers with 24 hydropower stations and several dams. The total installed power in the system is 43.75 MW. Most of the hydropower stations are regarded as small scale hydropower stations and thus entitled to green certificates.In this report the issue of planning is formulated as an optimization problem.
Förbättrad Kravhantering med hjälp av Lösningsinriktad Pedagogik
Abstract The purpose of writing this thesis was to improve methods during requirements engineering phase. Usercentred system engineering has some problem areas, which are examined and verified to create a new guideline for developers. This guideline tends to make requirements engineering more effective and help developers create more concrete requirements. It is not uncommon that system development projects ends up with unsatisfied users or delay in deliveries. The reasons are different kinds of communication problems between users and developers during verification of requirements.
Energianvändning för markkonstruktioner förlagda med ytvärme : En teknisk och ekonomisk utredning av fördelarna med att isolera under värmerören
The need for snow-free surfaces at squares, bus stops, platforms, car parks and sports facilities increases and at the same time energy price rise and the environment is becoming a hotter issue. The construction of the ground heating systems often lack thermal insulation under the heating pipes, which means that the heat from the pipes not only warm up the soil surface but also heats the surrounding soil. The insulation also has more features, by insulating the risk of frost damage is minimized. The goal of this report is to demonstrate the large heat loss and energy costs in the absence of insulation under the heating system.The report begins with a scientific way to study and treating the soil heating system uses, and the theory involved. Furthermore it also deals with different routing principles of heat pipes depending on the facility.All calculations are made with so called finite element method (FEM), in COMSOL Multiphysics 3,5a, where models are created with different conditions.
New Business Model for District Heating Firms Stabilizing the National Energy System with a Future Variable Electricity Production
The aim of this thesis is to develop a new business model for district heating and cooling firms which can contribute to a stabilization of the Swedish national energy system. The business model is developed for a district heating and cooling firm and is exemplified with Fortum Heat. The theoretical investigation around the topic creates a rigid base for following qualitative empirical studies. Osterwalder?s canvas for business model generation is used together with a Casual Loop Diagram to identify a number of business opportunities which stabilizes the national energy system.
En indirekt metod för adaptiv reglering av en helikopter
When a helicopter is flying, the dynamics vary depending on, for example, speed and position. Hence, a time-invariant linear model cannot describe its properties under all flight conditions. It is therefore desirable to update the linear helicopter model continuously during the flight. In this thesis, two different recursive estimation methods are presented, LMS (Least Mean Square) and adaptation with a Kalman filter. The main purpose of the system estimation is to get a model which can be used for feedback control.
En ny metod för intraoral röntgenundersökning på häst :
A method for equine intra oral radiology has been tested. In the study, both a digital system with an intraoral sensor connected to a laptop and a system utilizing image plates and digital developing was tested, initially on cadaver sculls and finally on sedated horses.
The digital sensor was not considered viable for this purpose, while the system with image plates and digital developing worked very well. Two different techniques, i.e. parallel and bisectris, are suggested for the best visualization of different parts of the teeth. Intra carious injections of Mixobar oesophaghus contrast fluid was found useful when evaluating the extent of carious lesions.
Compared to extra oral radiology, the new method had several advantages and can be used both in clinic and field practices..
Förbättrad Kravhantering med hjälp av Lösningsinriktad Pedagogik
Abstract
The purpose of writing this thesis was to improve methods during requirements
engineering phase. Usercentred system engineering has some problem areas, which
are examined and verified to create a new guideline for developers. This
guideline tends to make requirements engineering more effective and help
developers create more concrete requirements.
It is not uncommon that system development projects ends up with unsatisfied
users or delay in deliveries. The reasons are different kinds of communication
problems between users and developers during verification of requirements.
There is a therapy model, called solution-focused therapy, used in family and
individual therapy. The model focuses on solutions for the future instead of
problems in the past.
Styrning mot förändring: En fallstudie rörande organisatorisk förändring i offentlig sektor
This paper examines and analyzes effects of the introduction of a new management control system tool within a Swedish public health organization, the Södra Älvsborg hospital, and its possible effect on organizational change. The new management control system tool, known as the SÄS-model, has been widely criticized for being too costly and with too small positive effects to be shown. Our approach has with that as a background been to examine whether the implementation of the SÄS-model and its balanced scorecard has been able to result in effects regarding organizational change. We have through a case study aimed to analyze how a management control system, much alike one that is typically used within foremost private organizations, can promote organizational change. Our results suggest that the implementation of the SÄS-model and the balanced scorecard has given the organization clearer visions and goals.
Modellbygge av mekaniksystem och riktmotorer i stridsvagn 122
This master thesis is one part of a project, called ?StabSim?, with the purpose to develop a simulation model for the align and stabilisation system in main battle tank 122. The origin of this project is that it should be possible to make control analysis without risking any hardware. Besides that it will be easy to change components in order to investigate the behaviour of the system. The report includes modelling of tower and weapon mechanics and also the modelling of the synchronous motors, which control these.
Kommunikationsstrategi för Renbruksplan : är det en fungerande modell för samebyarna vid samråd?
The reindeer planning system (Renbruksplanen, RBP) is a communication and planning tool designed for Sami groups. A key purpose of this is that it will act as a tool in consultation with other market players, including forestry. Sami groups have asked for a model of how this can be used in a flexible manner. With the Swedish Forest Agency as a project manager, a communication model for how to use the RBP has been designed. It consists of a number of points divided into ?before?, ?during? and ?after? the consultation.
Ekonomistyrning i den svenska sjukvården: En utvärdering av KPP-systemet
This thesis analyses the cost accounting system KPP and its use within the Swedish health care. KPP is designed to calculate and assign health care costs to individual patients. This would facilitate evaluations and comparisons of the costs for certain diagnosis, patient groups or clinics with a different mix of diagnosis. The study investigates the following questions: 1. Does the KPP-model theoretically work as a cost accounting tool for health care purposes? 2.
Frekvensreglering i det nordiska kraftsystemet
Svenska Kraftnät is (together with the other transmission system operators of the Nordic power system) responsible for keeping balance between the generated and demanded power in the Nordic power system. Spontaneous load variations and system disturbances, however, lead to power imbalance followed by frequency variations. The frequency deviations can be limited to an acceptable level by the spinning reserve, mainly by hydro power control. But there are also other system properties which have a great influence on the frequency and system stability. The frequency and voltage dependence of the loads have a direct influence on the power balance.