There are a great many problems in generalizing classical 1D systems theory to multidimensional (nD) systems, i.e. systems which propagate information in two or more separate directions. Recent years have seen the eme...
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There are a great many problems in generalizing classical 1D systems theory to multidimensional (nD) systems, i.e. systems which propagate information in two or more separate directions. Recent years have seen the emergence of the so-called behavioural approach to systems theory which holds the promise of providing for the first time a framework in which all the important concepts of systems theory for nD systems can be expressed. This paper reports further development based on this general approach in the context of the pole/zero structure of an nD linear system.
Recent years have seen progress in the introduction of information systems to support the administration of electrical facilities, and applications of information on operations and facilities is now becoming properly ...
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Recent years have seen progress in the introduction of information systems to support the administration of electrical facilities, and applications of information on operations and facilities is now becoming properly regulated. Advances in the areas of data processing technology and network technology are contributing to improvements in the functions of support systems. These technologies make possible both the processing of increased volumes of information and the transmission of a wide variety of information. They also address the needs of facilities administration by increasing the ease with which information is communicated between information processing sites, among other things. The procedures addressed by support systems can be divided into three categories: (1) Reporting on the state of facilities operations;(2) Planning for facilities installation and maintenance;and (3) Diagnostic and evaluative reviews of facilities. The "Information Collection System for Operations Sites" is a system and product supporting the reporting of the state of facilities operations. Utilizing multipurpose equipment, in addition to its basic functions of transmitting images and sounds from a site, the system is capable of having memos added to its images, and it is capable of accurately reporting the state of events at a site. Information databases used in planning for facilities installation and maintenance are effective in that they are able to have multifaceted and rapid examinations performed on them. Via the internal network of a power-generating station, the "General Maintenance Administration Support System" makes possible the administration of facilities, administration of work being performed, administration of construction, and administration of operations. There is a trend towards even further progress in the application of support systems to diagnostic and evaluative reviews of facilities. Under the "BWR Water Chemistry Management System," the results of diagnostic re
A Markov-like weighted least squares (WLS) estimator is presented herein for harmonic sinusoidal parameter estimation. The estimator involves two distinct steps whereby it first obtains a set of initial parameter esti...
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A Markov-like weighted least squares (WLS) estimator is presented herein for harmonic sinusoidal parameter estimation. The estimator involves two distinct steps whereby it first obtains a set of initial parameter estimates that neglect the harmonic structure by some standard sinusoidal parameter estimation technique, and then the initial parameter estimates are refined via a WLS fit. It is found that the proposed estimator achieves similar performance to the optimal nonlinear least squares method when the signal-to-noise ratio (SNR) is moderate or high, but at a significantly reduced computational complexity. Furthermore, the former is shown to have a lower threshold SNR than the latter.
An important aspect of linear controller design is to clarify whether the design reaches the performance limit. Based on an industrial project-a high precision three-axis gyro test table (servo system), a paradigm is ...
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An important aspect of linear controller design is to clarify whether the design reaches the performance limit. Based on an industrial project-a high precision three-axis gyro test table (servo system), a paradigm is presented to demonstrate that the performance limit of the disturbance attenuation design of the servo system can be reached in a systematic way by using the μ -synthesis. Moreover, this paper reveals that the performance limit is determined by the bandwidth. This finding will help the designer to judge whether any given performance specification is achievable.
This paper describes B-spline interpolation and compares it with other reconstruction methods, especially in three-dimensional space. We first consider the B-spline bases in the terms of convolution in signal processi...
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This paper describes B-spline interpolation and compares it with other reconstruction methods, especially in three-dimensional space. We first consider the B-spline bases in the terms of convolution in signal processing. The presented analysis requires careful usage of continuous and discrete representation of B-spline. Emphasis is given to the important difference between B-spline interpolation and approximation. The difference is shown through frequency domain analysis, so we derive frequency responses of the B-spline interpolation and approximation. We conclude by demonstrating the use of several reconstruction filters and appropriate gradient estimators in volume rendering. Exact reconstruction in volume visualization is very important in many industrial applications, such as material cavity control.
We investigate herein the problem of amplitude estimation of sinusoidal signals from observations corrupted by colored noise. A relatively large number of amplitude estimators are described which encompass least squar...
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We investigate herein the problem of amplitude estimation of sinusoidal signals from observations corrupted by colored noise. A relatively large number of amplitude estimators are described which encompass least squares (LS) and weighted least squares (WLS) methods. Additionally, filterbank approaches, which are widely used for spectral analysis, are extended to amplitude estimation. Specifically, we consider the matched-filterbank (MAFI) approach and show that, by appropriately designing the prefilters, the MAFI approach includes the WLS approach. The amplitude estimation techniques discussed in this paper do not model the noise, and yet they are all asymptotically statistically efficient. It is their different finite-sample properties that are of particular interest to this study. Numerical examples are provided to illustrate the differences among the various estimators. Though amplitude estimation applications are numerous, we focus on system identification using sinusoidal probing signals.
The volume data is generally in the form of the large array of numbers. In order to render the object hidden in the volumetric data, we need to reconstruct or interpolate data values between the samples. The novelty p...
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The volume data is generally in the form of the large array of numbers. In order to render the object hidden in the volumetric data, we need to reconstruct or interpolate data values between the samples. The novelty presented in this paper is B-spline interpolation in the volumetric space. We show that this approach is better than currently used methods. We also present a hybrid approach, analyze this approach in frequency domain and compare it to B-spline interpolation. To enhance the quality during the volume visualization process it is important to enhance the quality of the reconstruction. It is of crucial importance to explore different undesired effects. If better reconstruction is performed the more accurate result of volume visualization process is achieved.
Stateflow/sup TM/ is a MATLAB/Simulink toolbox that supports the development of executable specifications for discrete-state functions. It also supports general flowcharting of program functions. This paper describes ...
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Stateflow/sup TM/ is a MATLAB/Simulink toolbox that supports the development of executable specifications for discrete-state functions. It also supports general flowcharting of program functions. This paper describes a MATLAB program, sf2smv 2.0, that generates input for a symbolic model checking program, SMV, to verify properties of Stateflow/sup TM/ diagrams in Simulink. The SMV modules are constructed to reflect precisely the execution semantics in the simulation of Stateflow/sup TM/ diagrams. This extends previous work that created verification files that reflected an idealized version of the Stateflow/sup TM/ semantics. This paper describes how the principal Stateflow/sup TM/ execution rules are translated into SMV modules. Examples are used to illustrate the transformation procedures and their application to verify properties of executable specifications for control features in automotive powertrain control applications.
A standard design procedure for a single sided and longitudinal flux based linear switched reluctance machine is developed in this paper. The proposed design procedure utilises the rotating switched reluctance machine...
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A standard design procedure for a single sided and longitudinal flux based linear switched reluctance machine is developed in this paper. The proposed design procedure utilises the rotating switched reluctance machine design by converting the specifications of the linear machine in to the equivalent rotary machine. The machine design is carried out in the rotary domain which is then transformed back in to the linear domain. Such a procedure brings to bear the knowledge base and familiarity of the rotary machine designers to design a linear machine effectively. The paper contains the illustration of the proposed design procedure for a 4.8 m long prototype. An analysis procedure is developed with a magnetic model and results from it are verified with finite element analysis prior to construction of the prototype. Extensive experimental correlation in the form of inductance vs. position vs. current and propulsion force vs. position vs. current to validate the analysis and design procedure is given in the paper.
A variant of a low cost, four-quadrant converter topology for permanent magnet brushless DC (PMBDC) motor drives is proposed in this paper. It has the advantage of variable DC input voltage to the machine through a bu...
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A variant of a low cost, four-quadrant converter topology for permanent magnet brushless DC (PMBDC) motor drives is proposed in this paper. It has the advantage of variable DC input voltage to the machine through a buck-boost front-end power stage and hence low torque ripple at very low speeds, a desirable feature in high performance applications. It has a fixed commutation voltage, which is equal to the DC source voltage. Further, it is proved that the proposed power converter topology will enable the maximum extraction of power from PMBDC motor drives. In addition, the energization and commutation of machine phases can be achieved independently. Because of these features, the proposed topology provides high operational reliability for the motor drives.
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