Documents disponibles chez cet éditeur

Microprocessor based diesel engine health monitoring system / A. Kouloughli 

Public ISBD Titre : Microprocessor based diesel engine health monitoring system Type de document : texte imprimé Auteurs : A. Kouloughli, Auteur ; A. R. Daniels, Directeur de thèse Editeur : Bath [Royaume-Uni] : University of Bath Année de publication : 1983 Importance : 96 f. Présentation : ill. Format : 27 cm. Note générale : Mémoire de Master : Electrotechnique : Angleterre, University of Bath : 1983 Annexe f. 97 - 207 . Bibliogr. [3] f Langues : Anglais (eng) Mots-clés : Microprocessor  based  system Diesel  engine Torsional  vibration  analysis Simulation  test-rig Pulsating  shaft  speed Hooke's  joint  assembly Cyclic  disturbances Data  acquisition  system Magnetic  sensors Minicomputer  system Index. décimale : Ms00183 Résumé : The purpose of this project was to design and construct a microprocessor based system for diesel engine health monitoring. The torsional vibration analysis approach was examined as a means of assessing continuously the state of the engine. A simulation test-rig was designed and built in the university laboratory in order to investigate the idea. This system was constructed using a three phase electrical motor that could be operated with a pulsating shaft speed and a Hooke's joint assembly in order to introduce cyclic disturbances in the motor shaft speed, thereby allowing an initial study to be performed. A data acquisition system was developed which consisted of using magnetic sensors and associated hardware to measure engine shaft speed variations. The inverse function method discussed in chapter 2 was implemented for speed measurement. Speed data was collected by a microprocessor based system then transferred to the PDP11/34 minicomputer system. The PDP11/34 minicomputer system was used for data storage and display. It also aided the software development for data analysis. The communication between the two computer systems was achieved using an RS-232 serial data transmission link. The software developed consisted of two main sections. The first section organised data and check it from wild points. The second section developed two analytical techniques, one based on the correlation method and the pther based on the frequency spectrum and applied these techniques to data sets obtained experimentally. Results from the laboratory test rig showed that the magnetic transducer was capable of producing sufficiently accurate information to detect small changes in the engine shaft speed. Two series of tests were performed on a V16 Paxman large diesel engine. Each test consisted of forcing a 20% over-fuel into one of the engine cylinders and recording the outputs from the transducers. The first series of tests used only one sensor and three sensors were used in the second series of tests. Results from analysis of diesel engine data sets showed some promise but suggested that a continuous monitor program should be developed to detect the disturbance rather than a single shot analysis examined in this thesis. Microprocessor based diesel engine health monitoring system [texte imprimé] / A. Kouloughli, Auteur ; A. R. Daniels, Directeur de thèse . - Bath (Royaume-Uni) : University of Bath, 1983 . - 96 f. : ill. ; 27 cm. Mémoire de Master : Electrotechnique : Angleterre, University of Bath : 1983 Annexe f. 97 - 207 . Bibliogr. [3] f Langues : Anglais (eng) Mots-clés : Microprocessor  based  system Diesel  engine Torsional  vibration  analysis Simulation  test-rig Pulsating  shaft  speed Hooke's  joint  assembly Cyclic  disturbances Data  acquisition  system Magnetic  sensors Minicomputer  system Index. décimale : Ms00183 Résumé : The purpose of this project was to design and construct a microprocessor based system for diesel engine health monitoring. The torsional vibration analysis approach was examined as a means of assessing continuously the state of the engine. A simulation test-rig was designed and built in the university laboratory in order to investigate the idea. This system was constructed using a three phase electrical motor that could be operated with a pulsating shaft speed and a Hooke's joint assembly in order to introduce cyclic disturbances in the motor shaft speed, thereby allowing an initial study to be performed. A data acquisition system was developed which consisted of using magnetic sensors and associated hardware to measure engine shaft speed variations. The inverse function method discussed in chapter 2 was implemented for speed measurement. Speed data was collected by a microprocessor based system then transferred to the PDP11/34 minicomputer system. The PDP11/34 minicomputer system was used for data storage and display. It also aided the software development for data analysis. The communication between the two computer systems was achieved using an RS-232 serial data transmission link. The software developed consisted of two main sections. The first section organised data and check it from wild points. The second section developed two analytical techniques, one based on the correlation method and the pther based on the frequency spectrum and applied these techniques to data sets obtained experimentally. Results from the laboratory test rig showed that the magnetic transducer was capable of producing sufficiently accurate information to detect small changes in the engine shaft speed. Two series of tests were performed on a V16 Paxman large diesel engine. Each test consisted of forcing a 20% over-fuel into one of the engine cylinders and recording the outputs from the transducers. The first series of tests used only one sensor and three sensors were used in the second series of tests. Results from analysis of diesel engine data sets showed some promise but suggested that a continuous monitor program should be developed to detect the disturbance rather than a single shot analysis examined in this thesis.

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité	Spécialité	Etat_Exemplaire
Ms00183	Ms00183	Papier	Bibliothèque centrale	Mémoire de Master	Disponible

Documents numériques

KOULOUGHLI.A.pdf URL

The application of digital adaptive modelling to the identification of system parameters by using Lyapunov functions / M. Rima

Public ISBD Titre : The application of digital adaptive modelling to the identification of system parameters by using Lyapunov functions Type de document : texte imprimé Auteurs : M. Rima, Auteur ; J. K. M. MacCormac, Directeur de thèse Editeur : Bath [Royaume-Uni] : University of Bath Année de publication : 1984 Importance : 121 f. Présentation : ill. Format : 30 cm Note générale : Mémoire de Master : Electronique : Angleterre, University of Bath : 1984 Bibliogr. f. 134 - 136 . Annexes Langues : Anglais (eng) Index. décimale : Ms01184 Résumé : The purpose of this project is to design a digital adaptive model for the identification of system parameters by using Lyapunov functions. The structure of the unknown system (plant) is already assumed known or identified. A learning model approach is used to identify the plant parameters. It consists of the following elements; the unknown plant, the learning model and the identification mechanism. The techniques used in this thesis are applicable to higher order time-variant system identification. However to investigate and develop these methods a second order single input/single output linear plant was simulated for identification purposes. The learning model is time-varying second order linear differential equation, it is used as a part of the control system itself. The identification mechanism is derived from a Lyapunov function which ensures stability and at the same time convergence of the learning model parameters to those of the unknown plant. Applying Lyapunov function the plant is assumed to have an accessible state vector. In order to achieve digital identification, the explicit time-varying learning model and the identification mechanism are converted from the time-domain to the discrete-domain applying the bilinear transformation and frequency prewarping and then the cascade method. The micromaster refers to the microcomputer system used. It is based on a ZILOG Z-80, eight bit, microprocessor, and it is used as a digital controller. It executes the time-varying digital models which are used for the identification scheme. The communication between the analog unknown plant and the micro-computer system is achieved using a programmable interface board constructed during the project. Due to computing speed limitations it was agreed to apply the technique to a plant with a low natural frequency to demonstrate the feasibility of such a technique. Recent microprocessor development made the identification method suitable for higher bandwidth systems. The results indicate that Lyapunov technique using adaptive methods are capable of producing sufficiently rapid and accurate identification. Further research is required on a method of selection of the weighting matrix and convergence constant to ensure optimum identification. These factors could possibly be reoptimised as a function of the identification plant parameters for subsequent identification of a time-varying plant. The application of digital adaptive modelling to the identification of system parameters by using Lyapunov functions [texte imprimé] / M. Rima, Auteur ; J. K. M. MacCormac, Directeur de thèse . - Bath (Royaume-Uni) : University of Bath, 1984 . - 121 f. : ill. ; 30 cm. Mémoire de Master : Electronique : Angleterre, University of Bath : 1984 Bibliogr. f. 134 - 136 . Annexes Langues : Anglais (eng) Index. décimale : Ms01184 Résumé : The purpose of this project is to design a digital adaptive model for the identification of system parameters by using Lyapunov functions. The structure of the unknown system (plant) is already assumed known or identified. A learning model approach is used to identify the plant parameters. It consists of the following elements; the unknown plant, the learning model and the identification mechanism. The techniques used in this thesis are applicable to higher order time-variant system identification. However to investigate and develop these methods a second order single input/single output linear plant was simulated for identification purposes. The learning model is time-varying second order linear differential equation, it is used as a part of the control system itself. The identification mechanism is derived from a Lyapunov function which ensures stability and at the same time convergence of the learning model parameters to those of the unknown plant. Applying Lyapunov function the plant is assumed to have an accessible state vector. In order to achieve digital identification, the explicit time-varying learning model and the identification mechanism are converted from the time-domain to the discrete-domain applying the bilinear transformation and frequency prewarping and then the cascade method. The micromaster refers to the microcomputer system used. It is based on a ZILOG Z-80, eight bit, microprocessor, and it is used as a digital controller. It executes the time-varying digital models which are used for the identification scheme. The communication between the analog unknown plant and the micro-computer system is achieved using a programmable interface board constructed during the project. Due to computing speed limitations it was agreed to apply the technique to a plant with a low natural frequency to demonstrate the feasibility of such a technique. Recent microprocessor development made the identification method suitable for higher bandwidth systems. The results indicate that Lyapunov technique using adaptive methods are capable of producing sufficiently rapid and accurate identification. Further research is required on a method of selection of the weighting matrix and convergence constant to ensure optimum identification. These factors could possibly be reoptimised as a function of the identification plant parameters for subsequent identification of a time-varying plant.

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité	Spécialité	Etat_Exemplaire
Ms01184	Ms01184	Papier	Bibliothèque centrale	Mémoire de Master	Disponible

Field and laboratory studies concerning the geotechnical characteristics of some natural deposits around the south-Western region of England / Abdelghani Belouar

Public ISBD Titre : Field and laboratory studies concerning the geotechnical characteristics of some natural deposits around the south-Western region of England Type de document : texte imprimé Auteurs : Abdelghani Belouar, Auteur ; D. A. Cook, Directeur de thèse Editeur : Bath [Royaume-Uni] : University of Bath Année de publication : 1984 Importance : 106 f. Présentation : ill. Format : 30 cm. Note générale : Mémoire de Master : Génie Civil : Bath, University of Bath : 1984 Bibliogr. [12] f Langues : Anglais (eng) Mots-clés : Alluvial  deposits Soil  mechanics Slope  stability  analysis Critical  state  theory Bishop  method Index. décimale : Ms01284 Résumé : This thesis examine aspects of the alluvial deposits in Somerset, and compare some of the properties of the alluvium in relation to existing theories in Soil Mechanics. The geology of the Bristol region includes an unusual variety of deposits. In particular the recent alluvium characterises all aspects of a normally consolidated clay material. The steep valley sides surrounding the City of Bath are well known for the active superficial landslipping and the second chapter therefore is devoted to studies of the better known theories of slope stability. The Bishop method is then applied to a field investigation at the Cliffe hotel, Limpley Stoke, where, as a result of a rapid thaw following heavy snowfall a stability failure occurred in the hotel forecourt on a 16° - 18° slope. Chapter three then presents a summary of Critical State theory originally developed in Cambridge. The Critical state framework is seen to provide a more complete understanding of a basic soil behaviour. The fourth chapter applies Critical State to a set of triaxial tests on undisturbed samples from Shepton Mallet, Somerset, where the overall consistency in the test results suggested that Critical State theory could be reasonably applied. hapters five and six describe the Imperial College stress path cell, together with tests for the determination of the At-Rest coefficient of earth pressure (Ko) and the effective strength parameters on four samples of Somerset alluvium, two other local deposits, and one remoulded London clay. These tests covered a period of six months. Field and laboratory studies concerning the geotechnical characteristics of some natural deposits around the south-Western region of England [texte imprimé] / Abdelghani Belouar, Auteur ; D. A. Cook, Directeur de thèse . - Bath (Royaume-Uni) : University of Bath, 1984 . - 106 f. : ill. ; 30 cm. Mémoire de Master : Génie Civil : Bath, University of Bath : 1984 Bibliogr. [12] f Langues : Anglais (eng) Mots-clés : Alluvial  deposits Soil  mechanics Slope  stability  analysis Critical  state  theory Bishop  method Index. décimale : Ms01284 Résumé : This thesis examine aspects of the alluvial deposits in Somerset, and compare some of the properties of the alluvium in relation to existing theories in Soil Mechanics. The geology of the Bristol region includes an unusual variety of deposits. In particular the recent alluvium characterises all aspects of a normally consolidated clay material. The steep valley sides surrounding the City of Bath are well known for the active superficial landslipping and the second chapter therefore is devoted to studies of the better known theories of slope stability. The Bishop method is then applied to a field investigation at the Cliffe hotel, Limpley Stoke, where, as a result of a rapid thaw following heavy snowfall a stability failure occurred in the hotel forecourt on a 16° - 18° slope. Chapter three then presents a summary of Critical State theory originally developed in Cambridge. The Critical state framework is seen to provide a more complete understanding of a basic soil behaviour. The fourth chapter applies Critical State to a set of triaxial tests on undisturbed samples from Shepton Mallet, Somerset, where the overall consistency in the test results suggested that Critical State theory could be reasonably applied. hapters five and six describe the Imperial College stress path cell, together with tests for the determination of the At-Rest coefficient of earth pressure (Ko) and the effective strength parameters on four samples of Somerset alluvium, two other local deposits, and one remoulded London clay. These tests covered a period of six months.

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité	Spécialité	Etat_Exemplaire
Ms01284	Ms01284	Papier	Bibliothèque centrale	Mémoire de Master	Disponible