A concept of dynamic safety (CoDySa) has been developed primarily targeting the improvement of aircraft safety. CoDySa principles are based on an analysis of the operating cycle of aircraft. Implementation of CoDySa i...
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A concept of dynamic safety (CoDySa) has been developed primarily targeting the improvement of aircraft safety. CoDySa principles are based on an analysis of the operating cycle of aircraft. Implementation of CoDySa in practice presumes completing steps to modernize the existing system. The further development of the CoDySa principles are its ground-to-air communication architecture. Possibilities to upload safety-enhancing software components (safelets) have been proposed together with scenarios of their use. These safelets can help a pilot in certain situations. This paper is devoted to software development technologies which can be chosen to implement uploadable safelets. Two main candidates are compared, namely Java and Juice/Oberon. Issues such as code effectiveness and safety are emphasized. Juice/Oberon has been recognized as a better candidate for implementation of safelets.
This paper considers the parametric shifted H/sub /spl infin// problem of weighted interval plants. A sufficient condition is obtained on weighting function W(s) such that for any interval plant P(s, q, r) the maximal...
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(纸本)0780366387
This paper considers the parametric shifted H/sub /spl infin// problem of weighted interval plants. A sufficient condition is obtained on weighting function W(s) such that for any interval plant P(s, q, r) the maximal shifted H/sub /spl infin// norm of W(s)P(s, q, r) is achieved at one of the vertex weighted plants.
This paper introduces a new multi-mode scannable memory element which allows pseudorandom testing to be integrated with scan in sequential circuits without the need of any design changes. As in the case of scan, the n...
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This paper introduces a new multi-mode scannable memory element which allows pseudorandom testing to be integrated with scan in sequential circuits without the need of any design changes. As in the case of scan, the new element is used in place of regular flip-flops in the design library. Concurrent with normal operation, the design can accumulate a signature of the state variables in the scan-register configured as a multiple input signature analyzer (MISA). Thus virtually complete state observability is achieved without the need of scanning-out the state for each test-input. The pseudorandom states of the MISA can also be utilized as state inputs in pseudorandom testing. In this way, most faults are covered in a pseudorandom, `test per clock' mode. Only a few random pattern resistant faults require scan, greatly reducing test application time. Pseudorandom delay testing of the true normally active circuit paths is also possible. Two-pattern tests are supported. Finally, we show that the new memory element can also be used for fault-tolerant design.
A dynamical mathematical model of a water supply plant based on lumped parameters is described. A concept of its control system is proposed that ensures output pressure stabilisation under conditions of variable water...
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A dynamical mathematical model of a water supply plant based on lumped parameters is described. A concept of its control system is proposed that ensures output pressure stabilisation under conditions of variable water consumption and variable water recourses. The control system consists of inner control loops which control the flow of each pump station and of a superimposed control loop that controls the output pressure of the water supply plant. The pressure controller calculates the cumulative reference value of the water flow for all controlled pumps and from this value an algorithm for the flow distribution calculates the reference flow for each inner loop, taking into account the level of water accumulation in each water well. control performances of output pressure obtained by a conventional PI controller and a fuzzy logic based controller are compared.
The implementation of a new estimation method with alternative process models for the state estimation of the baker’s yeast fermentation is presented. Some of the implementation issues are discussed using the data ob...
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The implementation of a new estimation method with alternative process models for the state estimation of the baker’s yeast fermentation is presented. Some of the implementation issues are discussed using the data obtained from simulation tests.
Seasonal time series with dominant frequency components are very common in various information and control systems, biomedicine and environmental engineering. Methods for their analysis, modelling and prediction inclu...
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Seasonal time series with dominant frequency components are very common in various information and control systems, biomedicine and environmental engineering. Methods for their analysis, modelling and prediction include both linear and nonlinear structures using autoregressive models, adaptive systems and neural networks. The paper presents basic algorithms for preprocessing of such signals including their filtering and subsampling at first to enable the following efficient signal approximation, modelling and prediction. The main part of the paper presents the comparison of linear autoregressive models and neural networks with different transfer functions including wavelets as well. Resulting methods presented in the paper are applied for processing of real values representing the river Elbe flow at a selected measuring station to study their modelling and prediction. The paper compares results obtained both by classical and adaptive methods using system history and appropriate learning methods for model optimization.
A procedure for the postoptimal analysis of dynamic positioning control system of floating vessels is proposed. The control system design is based on the optimal constrained covariance control (OC 3 ). Using the OC 3 ...
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A procedure for the postoptimal analysis of dynamic positioning control system of floating vessels is proposed. The control system design is based on the optimal constrained covariance control (OC 3 ). Using the OC 3 technique, the disadvantages of the classical LQG optimal control technique are avoided. The presented numerical example illustrates the properties of the new approach.
Pachteret al. (1994) proposed a new method for parameters estimation of second-order dynamical system models of high-order real plants based on knowledge of the theoretical transient time Tu(onset delay, OD) and the s...
Pachteret al. (1994) proposed a new method for parameters estimation of second-order dynamical system models of high-order real plants based on knowledge of the theoretical transient time Tu(onset delay, OD) and the slope of the inflection tangent yn′(ti) (onset rate, OR) of experimental unit step responses (USRs). However, two equations in the paper are shown to be incorrect. Therefore, in this note we present the correct expressions for characteristic quantities of an alternative parametrization of the second-order system with ξ > 1.
Advances in signal processing allow us to model the audio signal in terms of mathematical representation. Compressed audio signal are also important for low-bit-rate media in order to minimize transmission cost. Appli...
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Advances in signal processing allow us to model the audio signal in terms of mathematical representation. Compressed audio signal are also important for low-bit-rate media in order to minimize transmission cost. Applications such as movies on compact disc, audio conferencing, and digital television also require a good model for the audio compression. We present a model for compressed audio signal. By varying different modelling parameters, we obtain the simulation result of the proposed model of the audio coder. Simulation results found that it has a good compression Ssignal-to-noise ratio compared with NICAM, CD, and OCF coders.
The paper present an efficient O(T/sup 2/) algorithm for the general single-item dynamic lot-sizing problem, where the time horizon spans over T periods, inventory levels are limited, and nonzero initial and safety st...
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The paper present an efficient O(T/sup 2/) algorithm for the general single-item dynamic lot-sizing problem, where the time horizon spans over T periods, inventory levels are limited, and nonzero initial and safety stock levels are assumed to exist. The properties of the model were previously found by the author (1992) to transform the problem of finding an optimal, extreme solution into an equivalent shortest-path problem in a multigraph, which is a nontrivial generalization of the Wagner-Whitin (1958) model. Although the resulted multigraph contains O(T/sup 3/) edges, this paper shows how to construct the shortest path solution in O(T/sup 2/) time. For this type of the lot-sizing problems, the resulted algorithm has the lowest complexity over known methods.
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