Showing papers by "Southeast University published in 2002"

The uncertain OWA operator

Abstract: The ordered weighted averaging (OWA) operator was introduced by Yager1 to provide a method for aggregating several inputs that lie between the max and min operators. In this article, we investigate the uncertain OWA operator in which the associated weighting parameters cannot be specified, but value ranges can be obtained and each input argument is given in the form of an interval of numerical values. The problem of ranking a set of interval numbers and obtaining the weights associated with the uncertain OWA operator is studied. © 2002 Wiley Periodicals, Inc.

Exponential stability and periodic oscillatory solution in BAM networks with delays

Abstract: Both exponential stability and periodic oscillatory solution of bidirectional associative memory (BAM) networks with axonal signal transmission delays are considered by constructing suitable Lyapunov functional and some analysis techniques. Some simple sufficient conditions are given ensuring the global exponential stability and the existence of periodic oscillatory solutions of BAM with delays. These conditions are presented in terms of system parameters and have important leading significance in the design and applications of globally exponentially stable and periodic oscillatory neural circuits for BAM with delays. In addition, two examples are given to illustrate the results.

The ordered weighted geometric averaging operators

Abstract: The ordered weighted averaging (OWA) operator was introduced by Yager.1 The fundamental aspect of the OWA operator is a reordering step in which the input arguments are rearranged in descending order. In this article, we propose two new classes of aggregation operators called ordered weighted geometric averaging (OWGA) operators and study some desired properties of these operators. Some methods for obtaining the associated weighting parameters are discussed, and the relationship between the OWA and DOWGA operators is also investigated. © 2002 Wiley Periodicals, Inc.

Correlation between mechanical properties and amount of dendritic α-Al phase in as-cast near-eutectic Al–11.6% Si alloys modified with strontium

Abstract: The amount of dendritic α-Al phase with varying Sr content in near-eutectic Al–11.6% Si alloy was measured by quantitative metallography analysis software and the correlation of mechanical properties of fully modified alloy with the amount of dendritic α-Al is discussed. Addition of Sr in Al–Si alloys results in a considerable increase of the amount of α-Al. Mechanical properties of the fully modified alloy are linearly related to the volume fraction of dendritic α-Al, which plays a key role in improving the mechanical properties of near-eutectic Al–Si alloys.

Alternative Concession Model for Build Operate Transfer Contract Projects

Abstract: This paper develops an alternative concession model for build operate transfer (BOT) infrastructure projects. The concession period is a measure for deciding when the project ownership will be transferred from the investor back to the government concerned; it also demarcates the benefits, authorities, and responsibilities between the government and private investors. Previous studies have developed various techniques and methods, mainly suggesting proper organization structure, contracting procedures, methods or project financing, and risk allocation strategies when BOT-contract projects are implemented. These works have provided effective methodologies for the development of BOT contracts. Nevertheless, it appears that little has been undertaken in studying the way to determine the concession period in a BOT contract. This paper critically reviews the principles of establishing the concession period in a BOT contract. Such a review leads to developing a quantitative model for determining a proper concession period that can protect the interest of both the government concerned and private investors. An example is given that indicates how the alternative model can be applied to determine the concession period of BOT infrastructure projects.

Label-free hybridization detection of a single nucleotide mismatch by immobilization of molecular beacons on an agarose film

Abstract: We developed a new technique to immobilize a set of molecular beacons on an agarose film-coated slide and found that it has the ability to identify a single nucleotide difference in label-free DNA targets. The annealing properties, specificity and hybridization dynamics of the present technique were compared with those of the conventional technique that directly immobilizes molecular beacons on a planar glass slide. It is demonstrated that the molecular beacon array on an agarose film has high quench efficiency, an excellent discrimination ratio for single nucleotide mismatches and a short detection time. We hypothesize that such a low fluorescence background and high specificity molecular beacon array will find practical applications in label-free, high-throughput mutation analysis and disease diagnosis.

Control of the optical band structure of liquid crystal infiltrated inverse opal by a photoinduced nematic-isotropic phase transition.

Abstract: Recently, photonic band gap (PBG) crystals with lattice parameters comparable to the wavelength of light have attracted much attention, because they offer unique ways in which to control the propagation of light. PBG crystals have applications in laser, quantum optical devices, and so on. For many of these applications, it is important to have the capability of tuning the photonic band structures. The fabrication of such tunable PBG crystals is still a challenge. In this paper, we proposed that switchable PBG crystals could be realized by taking advantage of the phase transition in liquid crystals induced by the photoisomerization of azo dyes. A dynamic change in the optical stop band was demonstrated. Such photoswitchable PBG crystals provide a method by which light can be routed using light.

Nonlinear magnetic circuit analysis for a novel stator-doubly-fed doubly-salient machine

Abstract: Summary form only given. The doubly-salient permanent-magnet (DSPM) machine takes the advantages of high power density and high efficiency, but still suffers from limited constant-power speed range and high PM material cost. We propose a novel topology, namely the stator-doubly-fed doubly-salient (SDFDS) machine, which not only solves the problems of the DSPM machine, but also offers the flexibility to on-line optimize the efficiency. In order to effectively analyze and efficiently optimize the proposed machine, a new nonlinear magnetic circuit (NMC) analysis approach is also proposed.

Uniqueness and value-sharing of entire functions☆

Abstract: In this paper, we study the uniqueness of entire functions and prove the following theorem. Let f ( z ) and g ( z ) be two nonconstant entire functions, n , k two positive integers with n > 2 k + 4. If [ f n ( z )] ( k ) and [ g n ( z )] ( k ) share 1 with counting the multiplicity, then either f ( z ) = c 1 e cz , g ( z ) = c 2 e − cz , where c 1 , c 2 , and c are three constants satisfying (−1) k ( c 1 c 2 ) n ( nc ) 2 k = 1, or f ( z ) ≡ tg ( z ) for a constant t such that t n = 1.

Microscopic surface contouring by fringe projection method

Abstract: This paper describes the use of optical fringe projection method for 3D surface profile and deformation measurement of micro-components. In this method, sinusoidal linear fringes are projected on a micro-component surface by a grating phase shifting projector and a long working distance microscope (LWDM). The image of the fringe pattern is captured by a high-resolution CCD camera and another LWDM and processed by phase-shifting technique. A simple procedure is described which enables calibration of the optical set-up for subsequent quantitative measurement of micro-components of unknown shapes. This method is relatively simple and accurate, and is capable of conducting fully automated measurements. In this paper, two micro-components, a micro-mirror ( 0.1 mm ×0.1 mm ) and a micro-electrode pad are used to demonstrate deformation measurement and microscopic surface contouring.

TIGR/MYOC gene sequence alterations in individuals with and without primary open-angle glaucoma.

Abstract: PURPOSE. To discover sequence alterations in the TIGR/MYOC gene associated with primary open-angle glaucoma (POAG) in Chinese subjects. METHODS. Two hundred one unrelated Chinese patients with POAG and 291 unrelated individuals without glaucoma, aged 50 years or more, were screened for sequence alterations in the TIGR/MYOC gene by polymerase chain reaction, conformation sensitive gel electrophoresis, and DNA sequencing. Up to 111 more control subjects were screened for some of the alterations. RESULTS. Fourteen sequence variants that lead to amino acid changes were identified. Seven were novel: Prol6Leu, Ala17Ser, Leu95Pro, Leu215Pro, Glu300Lys, Glu414Lys, and Tyr471Cys. Of these, Glu300Lys and Tyr471Cys were found only in POAG. Arg46Stop was found in 4 patients with POAG (2.0%) and 9 of 402 control subjects (2.2%); one control subject was homozygous. IOP showed a trend (P = 0.11) toward a decrease of 1.5 mm Hg among the control subjects, with Arg46Stop compared with matched control subjects without Arg46Stop. Gly12Arg occurred four times as frequently in control subjects as in patients, but the difference was not statistically significant. CONCLUSIONS. Gly12Arg might be negatively associated with POAG, suggesting a protective effect. Three patients with POAG had a sequence change not found in control subjects, for a frequency of possible disease-causing TIGR/MYOC mutations of 1.5% (95% confidence interval [CI] = 0.3%-4.3%). Arg46Stop occurred with similar frequency in patients with POAG and control subjects, suggesting that the reduced amount of TIGR/MYOC predicted to result from this truncation does not dramatically increase or decrease risk of glaucoma.

On global robust exponential stability of interval neural networks with delays

Abstract: In this paper, based on globally Lipschitz continuous activation functions, new conditions ensuring existence, uniqueness and global robust exponential stability of the equilibrium point of interval neural networks with delays are obtained. The delayed Hopfield network, bidirectional associative memory network and cellular neural network are special cases of the network model considered. All the results obtained are generalizations of some recent results reported in the literature for neural networks with constant delays.

Signal processing techniques in genomic engineering

Abstract: Now that the human genome has been sequenced, the measurement, processing, and analysis of specific genomic information in real time are gaining considerable interest because of their importance to better the understanding of the inherent genomic function, the early diagnosis of disease, and the discovery of new drugs. Traditional methods to process and analyze deoxyribonucleic acid (DNA) or ribonucleic acid data, based on the statistical or Fourier theories, are not robust enough and are time-consuming, and thus not well suited for future routine and rapid medical applications, particularly for emergency cases. In this paper, we present an overview of some recent applications of signal processing techniques for DNA structure prediction, detection, feature extraction, and classification of differentially expressed genes. Our emphasis is placed on the application of wavelet transform in DNA sequence analysis and on cellular neural networks in microarray image analysis, which can have a potentially large effect on the real-time realization of DNA analysis. Finally, some interesting areas for possible future research are summarized, which include a biomodel-based signal processing technique for genomic feature extraction and hybrid multidimensional approaches to process the dynamic genomic information in real time.

A novel approach to measuring class cohesion based on dependence analysis

Abstract: Classes are the basic modules in object-oriented (OO) software, which consist of attributes and methods. Thus, in an OO environment, cohesion mainly concerns how tight the attributes and methods of classes are. This paper discusses the relationships between attributes and attributes, attributes and methods, and methods and methods of a class based on dependence analysis. Then we discuss the properties of these relationships. According to these properties, this paper proposes a novel approach to measuring class cohesion. Our approach overcomes the limitations of previous class cohesion measures, which consider only one or two of the three relationships in a class. We also prove that this measure satisfies the properties that a good measurement should have.

Optimal replacement policy for a multistate repairable system

Abstract: In this paper, a deteriorating simple repairable system with k + 1 states, including k failure states and one working state, is studied. The system after repair is not ‘as good as new’ and the deterioration of the system is stochastic. Under these assumptions, we study a replacement policy, called policy N, based on the failure number of the system. The objective is to maximize the long-run expected profit per unit time. The explicit expression of the long-run expected profit per unit time is derived and the corresponding optimal solution may be determined analytically or numerically. Furthermore, we prove that the model for the multistate system in this paper forms a general monotone process model which includes the geometric process repair model as a special case. A numerical example is given to illustrate the theoretical results.

A geometric-process repair-model with good-as-new preventive repair

Abstract: This paper studies a deteriorating simple repairable system. In order to improve the availability or economize the operating costs of the system, the preventive repair is adopted before the system fails. Assume that the preventive repair of the system is as good as new, while the failure repair of the system is not, so that the successive working times form a stochastic decreasing geometric process while the consecutive failure repair times form a stochastic increasing geometric process. Under this assumption and others, by using geometric process we consider a replacement policy N based on the failure number of the system. Our problem is to determine an optimal replacement policy N such that the average cost rate (i.e., the long-run average cost per unit time) is minimized. The explicit expression of the average cost rate is derived, and the corresponding optimal replacement policy can be determined analytically or numerically. And the fixed-length interval time of the preventive repair in the system is also discussed. Finally, an appropriate numerical example is given. It is seen from that both the optimal policies N** and N* are unique. However, the optimal policy N** with preventive repair is better than the optimal policy N* without preventive repair.