In this paper we will show how to set up a practical bonus-malus system with a finite number of classes. We will use the actual claim amount and claims frequency distributions in order to predict the future observed c...
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Based on a frame theoretical formulation of irregular sampling, conditions on sampling points are derived. Our formulation and sampling conditions are applicable to all subspaces (e.g. shift invariant, Gabor, bandlimi...
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ISBN:
(纸本)0819441880
Based on a frame theoretical formulation of irregular sampling, conditions on sampling points are derived. Our formulation and sampling conditions are applicable to all subspaces (e.g. shift invariant, Gabor, bandlimited and bandpass subspaces). A focus is paid to the implementation of the algorithm in general. The method starts from constructing a pair of frames for a selected subspace, with which a sequence of sampling functions is fabricated based on a set of given irregular sampling points. The (irregular) sampling reconstruction is implemented through a frame-based iterative algorithm, which is guaranteed to converge. A Matlab package with a graphic user interface will be provided for users to view demos as well as try their own sampling reconstruction problems. Users are also allowed to construct their own subspaces. Parameters, sampling points and signals may all be entered by users. The program will automatically check for the fulfillment of the sampling conditions and provide a reconstruction of the signal. We believe that this is a useful tool for studies and practices of irregular samplings.
In this paper, we propose a speech enhancement technique. It is based on spectral subtraction method, which is one of the major techniques of speech enhancement. However, the enhanced output speech signal of the spect...
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ISBN:
(纸本)0780371011
In this paper, we propose a speech enhancement technique. It is based on spectral subtraction method, which is one of the major techniques of speech enhancement. However, the enhanced output speech signal of the spectral subtraction method is corrupted by "musical noise". The musical noise is art offensive noise for human listening. To reduce the musical noise, we adopt an iterative algorithm. The iterative algorithm is derived from the same idea as Wiener filtering for speech enhancement. We use the output signal of the spectral subtraction method as the input signal again. This process is iterated a few times. At every time when we iterate. the spectral subtraction method, we estimate the noise signal, in order to obtain a peculiarity of musical noise and subtract it Therefore we can reduce more musical noise for iterations.
It is well known that the iterative stepwise quantization algorithm is very powerful for the optimization of amplitude digital Fourier transform holograms. We suggest a pre-iterative process to uniform the histogram d...
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ISBN:
(纸本)081944121X
It is well known that the iterative stepwise quantization algorithm is very powerful for the optimization of amplitude digital Fourier transform holograms. We suggest a pre-iterative process to uniform the histogram distribution of the Fourier transform of the input image in order to reduce the reconstruction error of amplitude digital Fourier transform holograms. Simulation results show that the reconstruction error can be reduced much when our pre-iterative process is used in the iterative stepwise quantization algorithm.
It is difficult to know the details of material distribution in a fluidised bed. Electrical capacitance tomography (ECT) technology has been developed for imaging industrial processes containing dielectric materials. ...
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ISBN:
(纸本)0819438537
It is difficult to know the details of material distribution in a fluidised bed. Electrical capacitance tomography (ECT) technology has been developed for imaging industrial processes containing dielectric materials. This paper discusses the principles of ECT and presents the first experimental results of using ECT to measure gas/solids distribution in square circulating fluidised beds (CFB). A wide range of fluidisation conditions was tested, from bubbling to circulating fluidisation. It has been shown that over the range, ECT can provide solids concentration and voids distribution instantaneously. Different fluidisation regimes could also be identified from the reconstructed images.
Designing a. nonlinear H∞ control law requires solving the Hamilton-Jacobi-Isaacs (HJI) equations, which are a set of nonlinear partial differential equations. An algorithm for obtaining the Taylor series solution of...
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Designing a. nonlinear H∞ control law requires solving the Hamilton-Jacobi-Isaacs (HJI) equations, which are a set of nonlinear partial differential equations. An algorithm for obtaining the Taylor series solution of HJI equations was given in [5], which showed that the coefficients of the Taylor series were governed by an algebraic Ricatti equation, and a sequence of linear algebraic equations. An iterative algorithm was further developed in [6] that can significantly improve the computational efficiency over the algorithm given in [5]. In this paper, we will further consider the computer implementation of the algorithm developed in [5] and [6]. Our algorithm has been tested on a nonlinear benchmark control problem. A fifth-order controller is obtained with its performance compared with the linear and third order ones. Computational efficiency is also compared with the Gaussian elimination method.
In this payer, by applying the auxiliary variational principle technique, some existence theorems of solutions for a class of generalized mixed implicit quasi-variational inequalities are proved in Hilbert spaces. A n...
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In this payer, by applying the auxiliary variational principle technique, some existence theorems of solutions for a class of generalized mixed implicit quasi-variational inequalities are proved in Hilbert spaces. A novel and innovative iterative algorithm to compute approximate solutions is suggested and analyzed. The convergence criteria are also given. As special cases of these results, the open problem put forward by Noor is answered positively and some results of existence and algorithm of solutions for generalized implicit quasi-complementarity problems are also obtained. Our results are new and generalize a number of known results of mixed variational inequalities, mixed quasi-variational inequalities and quasi-complementary problems involving single-valued and set-valued mappings in recent literatures. (C) 2000 Elsevier Science Inc. All rights reserved.
Most edge-preserving image restoration algorithms preserve discontinuities that are larger than a prescribed threshold value, therefore noise components whose differences in neighboring pixels are larger than the thre...
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Most edge-preserving image restoration algorithms preserve discontinuities that are larger than a prescribed threshold value, therefore noise components whose differences in neighboring pixels are larger than the threshold become amplified unintentionally. We propose a noise-adaptive edge-preserving Image restoration algorithm based on a Markov random field image model. The proposed potential function is controlled by the weighting function to adaptively incorporate the discontinuities into the solution. To avoid undesirable amplification of the noise, we introduce a noise-adaptive threshold to each pixel difference. As a result, the potential function Varies its shape from a quadratic form to a concave form according to the amount of noise added to each pixel. In doing so, high-frequency components caused by strong noise are relatively more smoothed as with the quadratic potential function used, while edge components that have a small noise Intensity are well preserved. The smoothing functional to be minimized is formulated to have a global minimizer in spite of its nonlinearity by enforcing the convergence and convexity requirements. The effectiveness of the proposed algorithm is demonstrated experimentally. (C) 2000 society of Photo-Optical Instrumentation Engineers. [S0091-3286(00)01212-5].
The paper presents some results related to the optimal control approachs applying to inverse radiative transfer problems, to the theory of reflection operators, to the solvability of the inverse problems on boundary f...
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The paper presents some results related to the optimal control approachs applying to inverse radiative transfer problems, to the theory of reflection operators, to the solvability of the inverse problems on boundary function and to algorithms for solution of these problems.
The s-t max-cut problem is an NP-hard combinatorial optimization problem. In this paper an equivalent linearly constrained continuous optimization problem is formulated and an algorithm is proposed for approximating i...
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The s-t max-cut problem is an NP-hard combinatorial optimization problem. In this paper an equivalent linearly constrained continuous optimization problem is formulated and an algorithm is proposed for approximating its solution. The algorithm is derived from an application of a logarithmic barrier function, where the barrier parameter behaves as temperature in an annealing procedure and decreases to zero from a sufficiently large positive number satisfying that the barrier function is convex. The algorithm searches for a better solution in a feasible descent direction, which has a desired property that lower and upper bounds are always satisfied automatically if the step length is a number between zero and one. We prove that the algorithm converges to at least a local minimum point if a local minimum point of the barrier problem is generated for a sequence of descending values of the barrier parameter with zero limit. Numerical results show that the algorithm seems effective and efficient. (C) 2000 Elsevier Science Ltd. All rights reserved.
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