The paper discuss fundamental determinations of intelligent system for collecting, analysing and presentation of underwater environment information, currently in development under the contract of Ministry of science, ...
The paper discuss fundamental determinations of intelligent system for collecting, analysing and presentation of underwater environment information, currently in development under the contract of Ministry of science, technology and informatics of Republic Croatia. system is conceived as an *** few distinctive parts. In the middle of the system is a commercial, remotely operated underwater vehicle equipped with different sensors including video camera. Vehicle is controlled by computer located on the base ship through the umbilical cable. The second important part is a computerized system for selective collecting, analysing and presentation of underwater environment information. Beside the usual vehicle manual control, the system will posses a certain intelligent properties and reaction currently in development under the sub project: SUBMERSIBLE, SENSORS and EXPERT. Sub project SUBMERSIBLE includes theoretical investigation and development of - intelligent, automatic, self-protective vehicle reactions in hazardous situations. - sensory based vehicle control, from conventional auto depth and auto heading control, to more sophisticated vision-based control which includes dynamic scene and motion analysis, and vision-based obstacle-avoidance. Sub project SENSORS is dedicated to development of - system for intelligent and selective collecting of information obtained by sensors taking into account, the main mission task, and - fusion of information obtained by different sensors and their integration in complete picture of underwater environment. The third sub project EXPERT includes theoretical analysis and development of methods and procedures for - post processing of collected data including intelligent interpretation and incorporation of human knowledge about environment, - presentation of data and knowledge using "hypermedia" principles for interactive communication between user and machine. The paper presents fundamental determinations, the structure and meth
The paper presents a new approach to non-linear adaptive control for power systems using the properties of the degree of stability and the Lyapunov function. Sufficient conditions are derived for the existence of a st...
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The paper presents a new approach to non-linear adaptive control for power systems using the properties of the degree of stability and the Lyapunov function. Sufficient conditions are derived for the existence of a stabilizing adaptive control law given a non-linear varying system. These conditions are in terms of the controller parameters and apply to systems in which the parameters are not all known. Thus, the control law obtained is implemented by purely local feedback. The stability of the system with the adaptive control is illustrated by the results of a simulation of a single-machine system model.
An on-line scheme to failure diagnosis is proposed for dynamic systems under adaptive control, which is designed based on a direct approach to self-tuning regulator. Failure modes occurred in the system are assumed to...
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An on-line scheme to failure diagnosis is proposed for dynamic systems under adaptive control, which is designed based on a direct approach to self-tuning regulator. Failure modes occurred in the system are assumed to be described by unexpected changes in physical parameters of the system. The parameter changes in the controlled system can effectively be detected by using Kullback Discrimination Information (KDI) as an index for model discrimination. In order to decide whether the detected system parameter change is caused by a failure or not, a fuzzy inference approach to failure decision is considered. Some appropriate membership functions which describe fuzzy events of failures are constructed to perform the fuzzy inference. In this way, useful knowledge about failure modes which is available from, e.g., experts can be introduced into the model- based diagnosis technique. Simulation studies of a second-order damped oscillator have been carried out to demonstrate the effectiveness of the method.
The aim of this paper is to review concepts and techniques involved in Flexible Manufacturing systems and Computer Integrated Manufacturing systems under low cost perspectives. Those techniques, justified for large si...
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The aim of this paper is to review concepts and techniques involved in Flexible Manufacturing systems and Computer Integrated Manufacturing systems under low cost perspectives. Those techniques, justified for large size companies, may be also implemented on medium and small size companies if and only if limited investment is required. So, the availability of low cost components and the stablishment of adequated design objectives is considered vital at this point. A CAD/CAM industrial system implemented on a single processing centre is presented in order to illustrate the different issues of low cost in CIM.
A hierarchical scheme for the supervision level in adaptive control implementation has been conceived. The paper presents the modular description of this scheme and develops the interface block between the mathematica...
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A hierarchical scheme for the supervision level in adaptive control implementation has been conceived. The paper presents the modular description of this scheme and develops the interface block between the mathematical level and the logic level. The supervisory function is realized by an Expert system which has been developed in such a way that allows the treatment of both volatile an permanent data.
An on-line scheme to fault detection in adaptive controlsystems is proposed by introducing Kullbaek Discrimination Information (KDI) as a detection index. When a physical parameter change due to a failure has occurre...
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An on-line scheme to fault detection in adaptive controlsystems is proposed by introducing Kullbaek Discrimination Information (KDI) as a detection index. When a physical parameter change due to a failure has occurred in a system under adaptive control, the failure effect will hardly be visible in the output performance because of the adaptation mechanism. Such a parameter change is also difficult to detect by monitoring the regulator parameters, which are determined by a recursive identification based on the direct approach. Since the failure effect is reflected as a change in the predictor model used for the adaptive control design, the fault detection leads to a model discrimination problem. It has been shown that the KDI can be used as an effective distortion measure for the model discrimination and the index can be applied in a modified form to detect a fault on-line. Simulation studies on a second order damped oscillatory system have been carried out to demonstrate the efficiency of the method.
A 500 MW unit superheater temperature control loop structure and parameters design using a state-space based CADCS package STAFCON is described. Special control loop structure with disturbance generator model is devel...
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A 500 MW unit superheater temperature control loop structure and parameters design using a state-space based CADCS package STAFCON is described. Special control loop structure with disturbance generator model is developed to increase disturbance compensation capabilities. Simulation results and brief STAFCON system description are also given.
An effective algorithm for the calculation of stability regions in the plane of two control parameters is proposed. The algorithm is suitable for small computers. In comparison with the classical technique, the derive...
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An effective algorithm for the calculation of stability regions in the plane of two control parameters is proposed. The algorithm is suitable for small computers. In comparison with the classical technique, the derived algorithm requires fewer manual calculations. The program and its short characteristic equation is included. Utilization of the program is illustrated on an example of an automatically controlled power system having a ‘forced’ excitation system.
A practical fault detection scheme based on a model discrimination approach is proposed for dynamical systems with various failure modes which can not he explicitly described by mathematical representations. Using ARX...
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A practical fault detection scheme based on a model discrimination approach is proposed for dynamical systems with various failure modes which can not he explicitly described by mathematical representations. Using ARX modelling, the Kullback Discrimination Information (KDI) is adopted as a model distortion measure to detect dynamics failures. In order to calculate the KDI for finite but large data sets with-out dealing with very large matrices, we derive an iterative algorithm of low dimension based on Baye' rule. The KDI is used as a detection index in a thresholding approach. This detection scheme can be combined with identification to diagnose the system operating mode. The effectiveness of the method has been confirmed through a simulation study of a second order servo system.
The optimal stochastic approximation procedure (OSAP) is applied to the parameter identification problem of distributed parameter system (DPS) driven by random disturbances and observed through noisy measurements. Thi...
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The optimal stochastic approximation procedure (OSAP) is applied to the parameter identification problem of distributed parameter system (DPS) driven by random disturbances and observed through noisy measurements. This procedure is a stochastic approximation procedure (SAP) with an optimal gain sequence and an optimal transformation on the gradient of the objective function: these optimal values accelerate the convergence rate by minimizing the mean squared parameter estimation error, under the assumption that the density functions of the system and observation noises are known, or can be easily estimated. An example of parameter identification of a stochastic parabolic DPS is simulated on the digital computer. A comparison is made among the results of the optimal, the modified, the nominal first-order, and the nominal second-order SAP. It is shown that the OSAP gives higher accuracy and faster rate of convergence as compared to the nominal SAP
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