bluuebunny/crossref_metadata_2025 huggingface dataset:
REGULATED BIOLOGICAL SYSTEMS
Authors: CABANAC MICHEL , RUSSEK MAURICIO
Published: May 2003

Control theory is concerned mainly with the treatment of signals. This article takes into account that living beings not only treat information, but they are open systems traversed by flows of energy and mass. A new block diagram of the regulation process is proposed, taking into account this fundamental difference between engineered and living systems. This new diagram possesses both didactic and heuristic advantages.
DYNAMICAL BEHAVIOR OF KAUFFMAN NETWORKS WITH AND-OR GATES
Authors: GOLES ERIC , HERNÁNDEZ GONZALO
Published: May 2003

We study the parallel dynamics of a class of Kauffman boolean nets such that each vertex has a binary state machine {AND, OR} as local transition function. We have called this class of nets AON. In a finite, connected and undirected graph, the transient length, attractors and its basins of attraction are completely determined in the case of only OR (AND) functions in the net. For finite, connected and undirected AON, an exact linear bound is given for the transient time using a Lyapunov functional. Also, a necessary and sufficient condition is given for the diffusion problem of spreading a one all over the net, which generalizes the primitivity notion on graphs. This condition also characterizes its architecture. For finite, strongly connected and directed AON a non-polynomial time bound is given for the transient time and for the period on planar graphs, together with an example where this transient time and period are attained. Furthermore, on infinite but finite connected, directed and non planar AON we simulate an universal two-register machine, which allows us to exhibit universal computing capabilities.
RELIABILITY OF T-HELP IN PREVENTING AUTOIMMUNE ATTACK: PROBABILISTIC ESTIMATION
Authors: SIMON Z.
Published: May 2003

An estimation is given for the probability of autoimmune attack as a failure of the T-help mechanism which requires, for immune attack, recognition of the antigen by both of a TH -clone and a B or T-killer-clone. With approximative numerical estimates for number of self epitopes, number of TH , B and T-killer-clones and for the probability, p that a self epitope is recognized by such a clone, an upper limit of 0.5 for the probability of autoimmune attack (per human lifetime) is estimated. The probability p is calculated with the assumption of randomness in primary structures of self epitopes and B and T-cell receptors. Although of low reliability, due to the simplifying approximations, our estimate suggests that T-help could play the central role in preventing autoimmune attack.
BIFURCATION ANALYSIS OF A DETRITUS-BASED ECOSYSTEM WITH TIME DELAY
Authors: MUKHERJEE DEBASIS , RAY SANTANU , SINHA DILIP KUMAR
Published: May 2003

This article concentrates on the study of delay effect of a mangrove ecosystem of detritus, detritivores and predator of detritivores. Local stability criteria are derived in the absence of delays. Conditions are found out for which the system undergoes a Hopf bifurcation. Further conditions are derived for which there can be no change in stability.
AGGREGATION TO COLONIES OF THE GREEN ALGA PEDIASTRUM: EXPERIMENTS AND SIMULATIONS
Authors: GREWE MARC , MARKUS MARIO
Published: May 2003

We simulate the aggregation of zoospores of the green alga Pediastrum simplex into a planar colony — including radially outward cell orientation. The model assumptions are: cells are randomly kicked by flagella, an ellipsoidal boundary repells cells and flagella, overlapping cell surfaces lead to dissipative cell-cell repulsion, cell-cell attractive forces occur around arches close to the cell's surfaces, there is friction of the cells with the medium; the process ends by an extension of the attractive arches followed by the stop of flagellar propulsion and finally a change of cell shapes from spherical to nearly triangular with contact-inhibited horn-like extensions. These assumptions are directly observed or indirectly inferred from the literature, light microscopy (video recordings) and scanning electron microscopy. We perform calculations with cell numbers ranging from 4 to 64. Additional simulations permit to discard alternative models, including planarization via cell-cell attraction only, chemotaxis or cohesive intercellular gliding. Our model yields patterns agreeing well with symmetrical as well as with disordered natural aggregates.
REVIEW: THE ALGEBRAIC RELATIONAL THEORY AND ITS APPLICATIONS
Authors: ZARETZKY ALBA N.
Published: May 2003

This Review concerns the Algebraic Relational Theory of living systems as developed by Leguizamón and co-workers since 1973 and based on the categorical approach championed by Robert Rosen and his (ℳ, ℛ) systems. The Algebraic Relational Theory expanded, by using new mathematical developments such as lattice theory, the relational notions found in (ℳ, ℛ) systems with concepts such as material physical nature and extrinsic energy that reflect aspects of physical reality not captured by standard physical concepts like mass, energy or time. The Algebraic Relational Theory is another effort in the direction of developing a theory about the notion of biological organization.

The Review contains the foundations of the theory, the principal mathematical developments, and applications of the theoretical results to different biological problems. They are the substantial base from which new ideas could be developed. It also includes a synthesis of initial experiments connected with this area of research.

Carlos Leguizamón died in 1998. We had worked together for 20 years.
DETERMINING LOCAL SINGULARITY STRENGTHS AND THEIR SPECTRA WITH THE WAVELET TRANSFORM
Authors: STRUZIK ZBIGNIEW R.
Published: May 2003

We present a robust method of estimating the effective strength of singularities (the effective Hölder exponent) locally at an arbitrary resolution. The method is motivated by the multiplicative cascade paradigm, and implemented on the hierarchy of singularities revealed with the wavelet transform modulus maxima (WTMM) tree. In addition, we illustrate the direct estimation of the scaling spectrum of the effective singularity strength, and we link it to the established partition function-based multifractal formalism. We motivate both the local and the global multifractal analysis by showing examples of computer-generated and real-life time series.
ADMISSIBLE STRINGS AND ITERATED FUNCTION SYSTEMS
Authors: VALLIN ROBERT W.
Published: May 2003

A nonempty, compact set E ⊆ ℝn is sub-self-similar (s.s.s.) if [Formula: see text] where the Si are contracting similarities. This definition is due to Falconer who gave as one example the boundary of any self-similar set. In this paper we look at a way to describe the s.s.s. sets which are boundaries and see when a given s.s.s. set is the boundary of a self-similar set. We then go on to investigate admissible strings, which we introduce in this paper.
FRACTAL GEOMETRY OF POROUS MATERIALS
Authors: YUNG PARK
Published: May 2003

This paper is no longer available. Please contact "fractals@wspc.com"
GENERATION OF A FRACTAL LANDSCAPE USING NONLINEAR MATHEMATICAL MORPHOLOGICAL TRANSFORMATIONS
Authors: DAYA SAGAR B. S. , MURTHY K. S. R.
Published: May 2003

A third-order Koch quadric fractal is used to generate a fractal landscape. To generate this artificial landscape, nonlinear mathematical morphological transformations are used to topologically decompose the binary fractal basin. The decomposed regions of prominence are coded with different shades for better perception. The 3D surfaces are generated for the topologically decomposed and coded fractal, which resembles a landscape possessing alluvial fans, of interest to theoretical geomorphologists.
SLICES OF MULTIFRACTAL MEASURES AND APPLICATIONS TO RAINFALL DISTRIBUTIONS
Authors: LAMMERING BIRGER
Published: May 2003

We discuss the relationship between the multifractal functions of a plane measure and those of slices or sections of the measure with a line. Motivated by recent mathematical ideas about the relationship between measures and their slices, we formulate the "slice hypothesis," and consider the theoretical limitations of this hypothesis. We compute the multifractal functions of several standard self-similar and self-affine measures and their slices to examine the validity of the slice hypothesis. We are particularly interested in using the slice hypothesis to estimate multifractal properties of spatial rainfall fields by analyzing rainfall data representing slices of rainfall fields. We consider how rainfall time series at a fixed site and slices of composite radar images can be used for this purpose, testing this on field data from a radar composite in the USA and on appropriate time series.
LARGE DEVIATIONS OF MULTIFRACTAL MEASURES
Authors: VENEZIANO DANIELE
Published: May 2003

We analyze the extremes of stationary multifractal measures using large deviation theory. We consider various cases involving discrete multiplicative cascades: scalar or vector cascades with dependent or independent generators, bare or dressed measures, and marginal (single-point) or joint (multi-point) extremes. In each case, we obtain the scaling behavior of the probability of large deviations as the resolution of the cascade diverges. Existing rough exponential limits for scalar cascades are confirmed, whereas for other cases our scaling relationships differ from previously published results. For scalar cascades, we refine the rough limits by obtaining the asymptotic pre-factor to the exponential term. Based on these refined asymptotics, we propose a variant to the Probability Distribution/Multiple Scaling (PDMS) technique to estimate the co-dimension function c(γ).
GEOMETRY OF THE ANTENNAS IN THE MANDELBROT SET
Authors: DEVANEY R. L. , MORENO ROCHA M.
Published: May 2003

In the Mandelbrot set, the bulbs attached directly to the main cardioid are called the p/q-bulbs. The reason for this is that the largest component of the interior of these bulbs consists of c-values for which the quadratic function Qc(z) = z2 + c admits an attracting cycle with rotation number p/q. In this paper, we give a geometric method to read off p/q from the geometry of the antenna attached to the bulb.
BIVARIATE FRACTAL INTERPOLATION FUNCTIONS ON GRIDS
Authors: DALLA LEONI
Published: May 2003

In this paper, a method of construction of fractal interpolation functions (FIF) on random grids in ℝ2 is examined.
DETRENDED FLUCTUATION ANALYSIS OF CHROMATIN TEXTURE FOR DIAGNOSIS IN BREAST CYTOLOGY
Authors: EINSTEIN ANDREW J. , WU HAI-SHAN , GIL JUAN
Published: May 2003

Chromatin appearance in breast epithelial cells has been shown to have fractal properties, and detrended fluctuation analysis (DFA) is an effective method for characterizing the scaling in non-stationary fractal signals in terms of a scaling exponent. This study examines the use of DFA for the characterization of chromatin appearance in breast epithelial cells. Images of nuclei representative of fine-needle aspiration biopsies of the breast are characterized in terms of the scaling exponent for 19 patients with benign lesions and 22 patients with invasive ductal carcinoma. Characterizing patients by the standard deviations of the values of the scaling exponent for their representative nuclei, a statistically significant difference is noted between benign and malignant cases. This reflects that malignancies exhibit less variability in chromatin roughness than do benign cases. Previous logistic regression models for the diagnosis of breast epithelial cell lesions are improved upon by incorporating the standard deviation of the scaling exponent. Using leave-one-out cross-validation, the best logistic regression classifiers demonstrate a sensitivity of 95% and a specificity of 100%. A combination of DFA and lacunarity analysis is seen to provide the best approach to characterizing chromatin in breast epithelial cell nuclei.
MULTIFRACTAL SPECTRA AS A MEASURE OF COMPLEXITY IN HUMAN POSTURE
Authors: SHIMIZU YU , THURNER STEFAN , EHRENBERGER KLAUS
Published: May 2003

Human posture is the result of a complex control system. The joint output of several physiological — most likely nonlinearly interacting — processes leads to constant correctional movements which enable humans to stand upright. These correctional body movements reflect features of the underlying control mechanisms and have recently been shown to be multifractal processes. We analyze the movements of healthy quiet standing persons by means of wavelet-based multifractal spectra. We show that the functional form of these spectra depends on the mode of balance control. We compare the findings from a group of healthy persons to a group of patients suffering from balance disorders. As the main result we find that if balance control inputs, such as visual cues or tactile information are reduced, the dominant fractal exponent becomes smaller and the range of fractal exponents strongly narrows. We suggest to use a set of multifractal spectrum parameters as a "measure of complexity."
WAVE PROPAGATION THROUGH HOLLOW BODIES AND NOISE REDUCTION
Authors: GERMÈS SYLVAIN , STAWICKI CHRISTOPHE , AUBRY DENIS
Published: May 2003

Low frequency noise (2–200 Hz) reduction in the passenger compartment has emerged in the past few years as a crucial subject of research in the car industry. This kind of noise is mainly due to the panels' vibrations, therefore our aim is to decrease the part of structural energy that reach them, i.e., we want to increase the part of energy that dissipates while propagating in the car body frame. This approach requires the understanding of structural wave propagation through the beam like structure (pillar, cross members…) as well as reflection and transmission at the structural joints. This is the physical problem that we want to address in this paper.

Since car body frames are much too complex for physical understanding, we focused on simpler representative academic structures. We developed a numerical tool for the prediction and visualization of wave propagation, based on finite element models (FEM). Our FEM are first validated by comparison with experimental modal analysis, and then used for transient analysis. In both cases, the good agreement between calculations and experiments shows the reliability of our model and allows us to use it for wave propagation visualization. We illustrate our results by making a movie that helps to understand how waves propagate through a two hollow bodies junction.
TIME DOMAIN MODELING OF AXISYMMETRIC WAVE PROPAGATION IN ISOTROPIC ELASTIC MEDIA WITH CEFIT — CYLINDRICAL ELASTODYNAMIC FINITE INTEGRATION TECHNIQUE
Authors: SCHUBERT FRANK , KOEHLER BERND , PEIFFER ALEXANDER
Published: May 2003

The Elastodynamic Finite Integration Technique (EFIT), originally developed by Fellinger et al.,1–3 represents a stable and efficient numerical code to model elastic wave propagation in linearly-elastic isotropic and anisotropic, homogeneous and heterogeneous as well as dissipative and nondissipative media. In previous works, the FIT discretization of the basic equations of linear elasticity, Hooke's law and Cauchy's equation of motion, was exclusively carried out in Cartesian coordinates. For problems in cylindrical geometries it is more suitable to use cylindrical coordinates. By that, axisymmetric problems can be treated in a two-dimensional staggered grid in the r,z-plane. The paper presents an EFIT version for axisymmetric problems in cylindrical coordinates called Cylindrical EFIT (CEFIT). After demonstrating the accuracy of the numerical code by a comparison between simulation results and analytical solutions, different examples of application are given. These examples include modeling of sound fields of ultrasonic transducers, thermoelastic laser sources, geophysical borehole probes, impact-echo measurements in layered media, and load simulations of the European Spallation Source (ESS) mercury target.
ULTRASOUND PROPAGATION THROUGH A ROTATIONAL FLOW: NUMERICAL METHODS COMPARED TO EXPERIMENTS
Authors: MANNEVILLE SÉBASTIEN , PRADA CLAIRE , TANTER MICKAËL , FINK MATHIAS , PINTON JEAN-FRANÇOIS
Published: May 2003

Sound propagation through a vortex is studied numerically using two different techniques: ray-tracing and finite-differences. Geometrical acoustics and ray-tracing are shown to yield a good picture of the interaction between a sound wave and a vortex when the ratio of the vortex radius to the acoustic wavelength is larger than one. In particular, this technique allows to take into account finite-size effects such as edge waves and the results are compared to experimental data. The interest of the finite-difference approach is demonstrated for cases where sound scattering occurs. We show the ability of such a simulation to account for both sound scattering and finite-size effects. Those two numerical techniques are compared and their validity is investigated.
ACOUSTICS OF KINEMATICALLY COMPLEX SHEAR FLOWS
Authors: ROGAVA ANDRIA , POEDTS STEFAAN , MAHAJAN SWADESH
Published: May 2003

A new nonasymptotic method is presented that reveals an unexpected richness in the spectrum of acoustic fluctuations in a shear flow with nontrivial (kinematically complex) mean kinematics. The usefulness of the method is illustrated by analysing three different specific cases of compressible hydrodynamic shear flows. The temporal evolution of perturbations spans a wide range of nonexponential behavior from shear-modified oscillations, transitions between oscillatory and nonperiodic (vortical) modes of motion to monotonic growth. The principal characteristic of the revealed acoustic phenomena is their asymptotic persistence. Exotic regimes like "Echoing" as well as unstable (including parametrically driven) solutions are identified. Further areas of application, for both the method and the new physics, are outlined.
ON THE EFFICIENT IMPLEMENTATION OF THE INTEGRAL EQUATION METHOD IN ELASTODYNAMICS
Authors: GLUSHKOV EVGENY V. , GLUSHKOVA NATALYA V.
Published: May 2003

The authors deal with low-cost computer implementation of the integral equation method in application to wave excitation, propagation and diffraction phenomena in solids. Typically these are frequency domain problems of seismic and physical acoustics and of nondestructive testing. Fast codes are obtained basing on analytical extracting and taking account of singular and slowly converging components of the solution beforehand. The present paper gives ideas of several such approaches, which have already proved their efficiency in practical applications. More details including numerical examples and discussion of similar methods known from the literature can be found in the surveyed papers.1–12
NUMERICAL STUDY OF THE WAVE INSTABILITY PROBLEM WITH THE EFFECT OF THE TRANSVERSE VELOCITY COMPONENT TEX SYSTEM
Authors: ATTILI B. S.
Published: May 2003

We will numerically investigate the wave instability problem with the effect of the transverse velocity component. An accurate and easy to program finite difference scheme will be developed for this purpose. The eigenfunctions will be normalized and computed simultaneously with the eigenvectors. Numerical results will also be presented.
MECHANISM OF ACOUSTIC WAVE PROPAGATION: A REAL ROLE OF VIRTUAL SOURCES
Authors: LASOTA HENRYK
Published: May 2003

The Huygens problem of self-regeneration of the acoustic wave crossing a liquid medium is discussed in the paper. Equal weight of both elastic and kinetic aspects of mechanical waves in fluids is stressed. Two types of virtual surface sources are defined, reflecting local action of the pressure and particle velocity, respectively. They are applied by the author in calculations of secondary radiation from the wave front of the plane wave. The Dirac delta impulse has been used as a waveform, the wave thus being reduced to its own front. The results have been obtained analytically, thanks to some particularly "friendly" features of the operation of convolution with the delta distribution. The paper gives formal proof to Fresnel's intuitive explanation of the mechanism of the forward-only propagation of the wave with no backward effects.
COMPUTATION OF THE ULTRASONIC FIELD RADIATED BY SEGMENTED-ANNULAR ARRAYS
Authors: MARTINEZ O. , ULLATE L. G. , MONTERO F.
Published: May 2003

A method for computing the ultrasonic field radiated from segmented annular arrays is presented. Using the well known convolution-impulse response approach, an analytical expression for the spatial impulse response velocity potential from a segmented annular transducer valid for all spatial points is obtained. The array field is then calculated by superposition. The proposed solution allows us to predict transient and continuous wave pressure fields from segmented annular arrays without requiring any far-field or paraxial approximation. In order to evaluate the proposed method, an analysis of efficiency versus accuracy of the computational results is also incorporated.
SET DEFUZZIFICATION AND CHOQUET INTEGRAL
Authors: OGURA YUKIO , LI SHOUMEI , RALESCU DAN A.
Published: May 2003

In this paper, we discuss the defuzzification problem. We first propose a set defuzzification method, (from a fuzzy set to a crisp set) by using the Aumann integral. From the obtained set to a point, we have two methods of defuzzification. One of these uses the mean value method and the other uses a fuzzy measure. In the first case, we compare our mean value method with the method of the center of gravity. In the second case, we compare fuzzy measure method with the Choquet integral method. We also give there a sufficient condition so that the results in the last two methods are equivalent.
DISSONANCE — A MEASURE OF VARIABILITY FOR ORDINAL RANDOM VARIABLES
Authors: YAGER RONALD R.
Published: May 2003

We look at the issue of obtaining a variance like measure associated with probability distributions over ordinal sets. We call these dissonance measures. We specify some general properties desired in these dissonance measures. The centrality of the cumulative distribution function in formulating the concept of dissonance is pointed out. We introduce some specific examples of measures of dissonance.
LINEAR COALITIONAL GAMES AND THEIR FUZZY EXTENSIONS
Authors: MAREŠ MILAN , VLACH MILAN
Published: May 2003

The paper deals with fuzzifications of the coalitional game models in which the expected pay-offs of players and coalitions are known only vaguely. There exists a class of games, here we call them linear coalitional games, which can be modelled as games with, as well as without, side payments. In the deterministic case both types of models of a linear coalitional game lead to the same results. As the fuzzification of games with side-payments is based on other principles than the fuzzification of more general games without side-payments, the linear coalitional games offer situations in which both approaches to the fuzzification of coalitional game models can be compared and their differences can be clearly illustrated. In this paper the attention is focused to the analysis of concepts of superadditivity and core of coalitional games.
FUZZY C-MEAN: A STATISTICAL FEATURE CLASSIFICATION OF TEXT AND IMAGE SEGMENTATION METHOD
Authors: CHUAI-AREE S. , LURSINSAP C. , SOPHASATHIT P. , SIRIPANT S.
Published: May 2003

Classification of text and image using statistical features (mean and standard deviation of pixel color values) is found to be a simple yet powerful method for text and image segmentation. The features constitute a systematic structure that segregates one from another. We identified this segregation in the form of class clustering by means of Fuzzy C-Mean method, which determined each cluster location using maximum membership defuzzification and neighborhood smoothing techniques. The method can then be applied to classify text, image, and background areas in optical character recognition (OCR) application for elaborated open document systems.
COMPARATIVE STUDY OF CONTINUOUS HIDDEN MARKOV MODELS (CHMM) AND ARTIFICIAL NEURAL NETWORK (ANN) ON SPEAKER IDENTIFICATION SYSTEM
Authors: KASURIYA SAWIT , WUTIWIWATCHAI CHAI , ACHARIYAKULPORN VARIN , TANPRASERT CHULARAT
Published: May 2003

This paper reports a comparative study between a continuous hidden Markov model (CHMM) and an artificial neural network (ANN) on a text dependent, closed set speaker identification (SID) system with Thai language recording in office and telephone environment. Thai isolated digit "0–9" and their concatenation are used as speaking text. Mel frequency cepstral coefficients (MFCC) are selected as the studied features. Two well-known recognition engines, CHMM and ANN, are conducted and compared. The ANN system (multilayer perceptron network with backpropagation learning algorithm) is applied with a special design of input feeding methods in avoiding the distortion from the normalization process. The general Gaussian density distribution HMM is developed for CHMM system. After optimizing some system's parameters by performing some preliminary experiments, CHMM gives the best identification rate at 90.4%, which is slightly better than 90.1% of ANN on digit "5" in office environment. For telephone environment, ANN gives the best identification rate at 88.84% on digit "0" which is higher than 81.1% of CHMM on digit "3". When using 3-concatenated digit, the identification rate of ANN and CHMM achieves 97.3% and 95.7% respectively for office environment, and 92.1% and 96.3% respectively for telephone environment.
NONDESTRUCTIVE MATURITY DETERMINATION OF DURIAN BY FORCE VIBRATION AND ULTRASONIC
Authors: KONGRATTANAPRASERT W. , ARUNRUNGRUSMI S. , PUNGSIRI B. , CHAMNONGTHAI K. , OKUDA M.
Published: May 2003

The nondestructive determination of the maturity of durian is an important process for quality control. Since durian has specific properties, such as the thickness of peel, non-uniformity of shape, roughness of prickle skin, largeness of size etc., the nondestructive determination of the maturity is hard to perform. This paper proposes two approaches for determining maturity of durian by using nondestructive vibration and ultrasonic. The appropriate vibration and ultrasonic are directly transferred through durian in the region between prickles located at the middle of durian. The measurement of frequency response from vibration of durian is done by using laser doppler. The signal measured by laser doppler is processed to extract high frequency part by wavelet transform and convert into spectrum form. The template matching is performed by correlation between the high frequency spectrum of signal and templates in order to determine the maturity of durain. To evaluate the proposed method, two prototypes of system using force vibration and ultrasonic are constructed. The experiments are performed for comparing with the results of dry-weight percentage method that is considered to be absolutely right destructive way. And the results of template matching by correlation as proposed signal processing are also compared with conventional signal processing such as vibration velocity way and elastic constants way. The results reveal that the methods using force vibration and ultrasonic with template matching are more accurate by 95% approximately.
AEROSPACE APPLICATIONS OF INTERVALS: FROM GEOSPATIAL DATA PROCESSING TO FAULT DETECTION IN AEROSPACE STRUCTURES
Authors: KREINOVICH VLADIK , STARKS SCOTT A.
Published: May 2003

This paper presents a brief introduction into interval computations and their use in aerospace applications.
FROM PLANNING TO SEARCHING FOR THE SHORTEST PLAN: AN OPTIMAL TRANSITION
Authors: TREJO R. , GALLOWAY J. , SACHAR C. , KREINOVICH V. , BARAL C. , TUAN LE CHI
Published: May 2003

If we want to find the shortest plan, then usually, we try plans of length 1, 2, …, until we find the first length for which such a plan exists. When the planning problem is difficult and the shortest plan is of a reasonable length, this linear search can take a long time; to speed up the process, it has been proposed to use binary search instead. Binary search for the value of a certain parameter x is optimal when for each tested value x, we need the same amount of computation time; in planning, the computation time increases with the size of the plan and, as a result, binary search is no longer optimal. We describe an optimal way of combining planning algorithms into a search for the shortest plan – optimal in the sense of worst-case complexity. We also describe an algorithm which is asymptotically optimal in the sense of average complexity.
FUNDAMENTALS OF M-VAGUE ALGEBRA AND M-VAGUE ARITHMETIC OPERATIONS
Authors: DEMIRCI MUSTAFA
Published: May 2003

In the present work, the development of a new and general theory of algebraic concepts based on *-fuzzy equalities and strong fuzzy functions is begun, and several fundamental results are established under the name M-vague algebra. As a natural implementation of the M-vague algebraic approach, new kinds of arithmetic operations, namely M-vague arithmetic operations, are introduced using an approach different from the traditional approach to fuzzy arithmetic operations, and various kinds of M-vague algebraic properties of M-vague arithmetic operations are investigated.
FUZZY STRUCTURES ON HYPERK-ALGEBRAS
Authors: BORZOOEI RAJAB ALI , MEHDI ZAHEDI MOHAMMAD
Published: May 2003

In this note first we define the notions of fuzzy hyperK-subalgebra and fuzzy (weak) hyperK-ideal of a hyperK-algebra. Then we state and prove some equivalent conditions for these notions. In particular we conclude that any fuzzy hyperK-ideal is weak but the converse is not correct in general. After that under a suitable condition we show that a fuzzy subset is a fuzzy hyperK-subalgebra if and only if it is a fuzzy weak hyperK-ideal. Also we give a correspondence theorem for fuzzy hyperK-ideals. Finally by considering the notion of fuzzy strongest relation, we state and prove some related results. Also we give many examples throughout the manuscript.
PROGRAMMING APPROACH FOR FUZZY MODEL-BASED MULTIOBJECTIVE CONTROL SYSTEMS
Authors: BIEN ZEUNGNAM , KANG DONG-OH , YANG SE-HYUN
Published: May 2003

Many practical control problems for the complex, uncertain or large-scale plants, need to simultaneously achieve a number of objectives, which may conflict or compete with each other. If the conventional optimization methods are applied to solve these control problems, the solution process may be time-consuming and the resulting solution would often lose its original meaning of optimality. Nevertheless, the human operators usually perform satisfactory results based on their qualitative and heuristic knowledge. In this paper, we investigate the control strategies of the human operators, and propose a fuzzy model-based multi-objective satisfactory controller. We also apply it to the automatic train operation (ATO) system for the magnetically levitated vehicles (MAGLEV).
NECESSARY AND SUFFICIENT CONDITIONS FOR FUZZY TRUTH VALUES TO FORM A DE MORGAN ALGEBRA
Authors: EMOTO MASASHI , MUKAIDONO MASAO
Published: May 2003

Different fuzzy logics were shown to be particular cases of many kinds of algebras, such as Lukasiewicz algebra, Heyting algebra, de Morgan algebra, Kleene algebra, etc. In this paper, following the original definitions of fuzzy set operations proposed by L. A. Zadeh, we consider the set of all possible fuzzy truth values, the set which contains linguistic truth values such as "true", "very true", "more or less true", etc. We show that if we impose some conditions on fuzzy truth values, then the resulting set of fuzzy truth vlues with naturally defined logical operations forms a de Morgan algebra.
FUZZY/PROBABILITY ~ FRACTAL/SMOOTH
Authors: NGUYEN HUNG T. , KREINOVICH VLADIK , WU BERLIN
Published: May 2003

Many applications of probability theory are based on the assumption that, as the number of cases increase, the relative frequency of cases with a certain property tends to a number – probability that this property is true. L. Zadeh has shown that in many real-life situations, the frequency oscillates and does not converge at all. It is very difficult to describe such situations by using methods from traditional probability theory. Fuzzy logic is not based on any convergence assumptions and therefore, provides a natural description of such situations. However, a natural next question arises: how can we describe this oscillating behavior? Since we cannot describe it by using a single parameter (such as probability), we need to use a multi-D formalism. In this paper, we describe an optimal formalism for describing such oscillations, and show that it complements traditional probability techniques in the same way as fractals complement smooth curves and surfaces.
A TREATMENT OF USEFULNESS OF KEYWORDS IN FUZZY REQUESTS FOR AN INFORMATION RETRIEVAL SYSTEM WITH BAYESIAN NETWORKS
Authors: SAITO KENJI , SHIOYA HIROYUKI , DA-TE TSUTOMU
Published: May 2003

We improve a document retrieval method based on the so-called maximum entropy principle proposed by Cooper, and show how to implement this system on a Bayesian network. A Bayesian network is a probabilistic model for expressing probabilistic relations among random variables. We show advantages of a document retrieval system on a Bayesian network in comparison with Cooper's system.

The original document retrieval system based on the maximum entropy principle has a drawback: a result of retrieval can not be obtained in some cases. In this paper, we resolve this drawback by fuzzification of user retrieval requests.
DECENTRALIZED STABILIZATION OF COMPLEX SYSTEMS BY COMBINATION OF CONVENTIONAL AND FUZZY CONTROLS
Authors: THAI QUANG VINH , HA MANH DAO , HO SI BANG
Published: May 2003

In this paper, we deal with the problem of how to achieve stability for a complex system in which the subsystems are stable, but the non-linear interaction between the subsystems may cause instability. We assume that the uncertainties with which we know the parameters of the system are bounded, but that these bounds are not known. For such systems, we propose a new control method: a decentralized robust control with fuzzy estimation of the bounds of uncertainties, implemented as a combination of conventional and fuzzy controllers. The use of fuzzy control is motivated by the equivalent dynamic fuzzy state-space model of the system consisting of interconnected uncertain subsystems.
ON RELIABILITY OF SYSTEM COMPOSED OF PARALLEL UNITS SUBJECT TO INCREASING LOAD
Authors: VOLF PETR , LINKA ALEŠ
Published: May 2003

A system composed of a set of independent parallel components is considered and its resistance to an increasing load is modeled. The load is divided equally among all components (the load-sharing scheme). Failures (breaks) of components are regarded as the events of corresponding counting processes in statistical survival analysis. The objective is to estimate the distribution of breaking strengths of components (i.e., the load per component causing the breaks), to predict the breaking strength of the system, and to compare such a prediction with observed data by statistical tests.
INSPECTION PROGRAM DEVELOPMENT BY THE USE OF APPROVAL TEST RESULTS
Authors: PARAMONOV YU. M. , PARAMONOVA A. YU.
Published: May 2003

The use of p-set function and minimax approach is offered for inspection program development on a basis of lifetime approval test result processing. In this case, there is no need to resort to the dubious compromise choice of the required reliability and confidence probability.
GRÖBNER BASIS METHODS FOR STRUCTURING AND ANALYSING COMPLEX INDUSTRIAL EXPERIMENTS
Authors: PISTONE GIOVANNI , RICCOMAGNO EVA , WYNN HENRY P.
Published: May 2003

This work extends the research program of the authors into the design and analysis of complex experiments. It shows how the special algebraic structures studied in the polynomial ring algebra and Gröbner basis environment can be exploited for situations in which there is blocking, nesting, crossing and so on, or where groups of factors are "favoured" over others. The connection is made between the Gröbner basis methods and the more classical symbolic formalism associated, for example, with Generalised Linear Model packages, such as S-Plus and Glim. Examples are given from physical experiments in engine mapping.
STATISTICAL MONITORING AND CONTROL OF TOOL WEAR PROCESSES
Authors: XIE M. , GOH T. N. , WIKLUND H. , TANG X. Y.
Published: May 2003

Statistical control charts have been successfully used in industry for monitoring stable processes. However, processes with uncontrollable but acceptable trend are common in practice. One typical example is the wear process of cutting tools. Conventional control charts may not serve the purpose of process monitoring. In this paper, a forecast-based technique using Double Exponential Smoothing is proposed. It eliminates the trend component, and control charts are applied to the residuals. Furthermore, a procedure based on double control lines is suggested and adopted in tool wear process monitoring to integrate statistical and engineering properties for better decision making on tool wear-out. Other than the monitoring of tool wear process, the method can be used for better monitoring of other processes with trend. An actual tool wear data set is used as illustration.
WARRANTY AND PREVENTIVE MAINTENANCE
Authors: DJAMALUDIN I. , MURTHY D. N. P. , KIM C. S.
Published: May 2003

For products sold with warranty, preventive maintenance actions by manufacturers and/or buyers have an impact on the total costs for both parties. This paper develops a framework to study preventive maintenance actions when items are sold under warranty and reviews the models that have appeared in the literature. It then develops a new model and carries out its analysis.
An $(\tilde{X}/R)$-EWMA CONTROL CHART FOR MONITORING THE PROCESS SAMPLE MEDIAN
Authors: CASTAGLIOLA PHILIPPE
Published: May 2003

The method proposed in this paper is a new EWMA type control chart, dedicated to the monitoring of the process sample median [Formula: see text]. Because this control chart uses the range of the process, we call it a [Formula: see text]-EWMA control chart. In this paper, we show how to compute the control limits of this chart, give an illustrative example, describe how to compute the ARL and how to obtain optimal parameters minimizing the out-of-control ARL.
PERFORMANCE OF SENSITIZING RULES ON SHEWHART CONTROL CHARTS WITH AUTOCORRELATED DATA
Authors: BALKIN SANDY D. , LIN DENNIS K. J.
Published: May 2003

Sensitizing Rules are commonly applied to Shewhart Charts to increase their effectiveness in detecting shifts in the mean that may otherwise go unnoticed by the usual "out-of-control" signals. The purpose of this paper is to demonstrate how well these rules actually perform when the data exhibit autocorrelation compared to non-correlated data. Since most control chart data are collected as time series, it is of interest to examine the performance of Shewhart's [Formula: see text] Chart using data generated from typical time series models. In this paper, measurements arising from autoregressive (AR), moving average (MA) and autoregressive moving average (ARMA) processes are examined using Shewhart Control Charts in conjunction with several sensitizing rules. The results indicate that the rules work well when there are strong autocorrelative relationships, but are not as effective in recognizing small to moderate levels of correlation. We conclude with the recommendation to practitioners that they use a more definitive measure of autocorrelation such as the Sample Autocorrelation Function correlogram to detect dependency.
TESTING-DOMAIN DEPENDENT SOFTWARE RELIABILITY GROWTH MODELS AND THEIR COMPARISONS OF GOODNESS-OF-FIT
Authors: YAMADA SHIGERU , FUJIWARA TAKAJI
Published: May 2003

A software developer has to test to verify the implemented functions based on its requirement specification. We use many various test-cases for testing. Then, there is a set of the modules and functions in the software system to be influenced by the executed test-cases. The set is called a testing-domain and it spreads with the progress of testing. The growth rate of testing-domain in the software system is closely related to the quality and quantity of the executed test-cases by testing. Further, the quality of test-cases is related to the testing-skill of test-case designers. In this paper, we discuss testing-domain dependent software reliability growth models. The models are formulated by a nonhomogeneous Poisson process. Further, we propose three kinds of testing-domain, i.e., the basic testing-domain, the testing-domain with skill-factor, and the testing-domain with imperfect debugging. Finally, these models are applied to fault data observed in actual development projects, the software reliability analysis results are shown, and the comparisons of goodness-of-fit with the conventional software reliability growth models are performed.
MARKOVIAN MODELING FOR SOFTWARE AVAILABILITY ANALYSIS UNDER INTERMITTENT USE
Authors: TOKUNO KOICHI , YAMADA SHIGERU
Published: May 2003

We discuss the software availability modeling when the system is used intermittently. From the viewpoint of users, occurrence of a system failure is recognized when the event that either a software failure occurs when the system is in use or a usage demand occurs when the system is under restoration arises. In this pape, a couple of new measures for software availability assessment are derived; these are called the disappointment probabilities in use and under restoration, respectively. It is supposed that the usage demand of the system occurs randomly and that the user's demand duration is also random. The time-dependent behavior of the system alternating between up and down states is described by a Markov process. Then the software reliability growth process, the upward tendency in difficulty of debugging, and the imperfect debugging environment are also considered.
ALL-OPTICAL POWER LIMITING
Authors: POTASEK M. , KIM S. , MCLAUGHLIN D.
Published: May 2003

We derived a numerical technique for the propagation of the electromagnetic field in a five-level reverse saturable absorber including the nonlinear Kerr effect and dispersion. The numerical method combines the split step beam propagation method and the Crank–Nicholson method. Using our numerical technique we observed new behavior, not previously observed nor predicted to our knowledge, including the temporal splitting caused by the dynamics of the carrier densities in a reverse saturable absorber and the enhancement of absorption due to the Kerr nonlinearity. Our numerical calculation enables the prediction of nonlinear absorption using material parameters such as the absorption cross-sections and decay rates. We can also investigate the interplay between the optical pulse properties such as the temporal pulse width, spatial radius, incident energy and the carrier dynamics and nonlinear absorption of the reverse saturable absorber.
PICOSECOND OPTICAL LIMITING PERFORMANCE OF A NOVEL PPV-ZnPc CONJUGATED POLYMER
Authors: YU JINGJIN , WANG LIMING , WANG QING , NG MANKIT , YU LUPING
Published: May 2003

A novel ZnPc monomer as well as PPV-ZnPc conjugated polymers have been synthesized and their optical power limiting (OPL) performances toward picosecond laser pulses at 532 nm have been measured. The comparison with the performance of C 60 under the same condition indicates that two of the compounds synthesized outperformed C 60 at picosecond time scale. It was found that conjugated PPV polymers containing a small amount of ZnPc cannot only preserve, but have also showed improvement over the monomer's OPL properties. It is believed that the backbone modification was responsible for the enhanced OPL performance.
OPTICAL LIMITING INDUCED BY CAVITY FEEDBACK IN A RESONANT DENSE MEDIUM
Authors: BRUNEL M. , SANCHEZ F.
Published: May 2003

We investigate the optical limiting behavior exhibited by a resonant dense medium when inserted in a ring cavity. The influence of the cavity parameters, the atomic frequency detuning and the density of atoms are determined.
PICOSECOND REVERSE SATURABLE ABSORPTION AND OPTICAL LIMITING IN FULLERENES AND THEIR METAL DERIVATIVES
Authors: CALLAGHAN J. , BLAU W. J. , HENARI F. Z.
Published: May 2003

Investigations of the reverse saturable absorption behaviour of Fullerenes C 60 and C 70 and some of their Pt and Pd metal derivatives have been carried out with picosecond pulses at 532 nm. From intensity dependent transmission measurements, coupled with a population level kinetic analysis, excited state cross sections were determined for the materials. These show that C 60 possesses the largest excited state to ground state cross-section ratio and that, of the materials studied, it offers the best optical limiting ability around 532 nm. C 70, due to its large ground state absorption, has been shown not to be an efficient limiter. The metal derivatives perform better than C 70 but less efficiently than C 60.
BROADBAND OPTICAL LIMITING USING TANDEM FILTERS WITH MULTIPHOTON ABSORBER AND REVERSE SATURABLE ABSORBERS
Authors: FENEYROU P.
Published: May 2003

We report experimental results on a tin phthalocyanine: the nanosecond transient spectroscopy shows a reverse saturable absorption between 490–530 nm and 550–700 nm and the nonlinear transmission provides a better optical power limiting efficiency from 570 nm to 700 nm compared to C 60. This molecule is then combined in a tandem filter with a multiphoton absorber and a mixture of reverse saturable absorbers to achieve neutral-color broadband protection against ns pulses: the transmitted energy is clamped below 2 μ J throughout the visible.
LASER BEAM SELF-FOCUSING IN PHOTOREFRACTIVE MATERIALS: OPTICAL LIMITING APPLICATION
Authors: WOLFERSBERGER D. , FRESSENGEAS N. , MAUFOY J. , KUGEL G.
Published: May 2003

This paper presents a way to achieve optical limiting using the self-focusing of a laser beam in a photorefractive medium. In this view, the protection is not based on the absorption of the beam energy in the limiting system but on a global defocusing of the light in the optical system. We have studied experimentally and theoretically the self-focusing of a single laser beam in electrically biased Bi 12 TiO 20 from the continuous to the pulsed regime. We show that photorefractive materials are, for given conditions, efficient against laser radiation on these two different time scales at a low energy level (nJ).
DUAL FOCAL PLANE VISIBLE OPTICAL LIMITER
Authors: HERNÁNDEZ F. E. , YANG S. S. , DUBIKOVSKIY V. , SHENSKY W. , VAN STRYLAND E. W. , HAGAN D. J.
Published: May 2003

Experiments measuring the transmission of 5 nanosecond (FWHM), 532 nm pulses through an optical limiter using two different nonlinear materials at two separate focal planes show by far the highest dynamic-range measured to date. This cascaded focus, f/5 optical limiter combines self focusing and consequent nonlinear scattering in CS 2, with reverse saturable absorption in lead-phthalocyanine (PbPc). Both the AC Kerr effect and electrostriction contribute to the total refractive index change in CS 2. Our beam propagation code is used to model the propagation of light through the 2 cm thick CS 2 cell placed at the first focus, which protects a second 0.1 mm cell containing a solution of PbPc placed at the second focus. An aperture is placed in the focal plane of a final focusing lens to measure the "encircled" energy, defined as the energy passing through a 1.5 mrad diameter focal-plane aperture. Experiments and modeling show that the strong self-focusing in the CS 2 keeps the energy at the second cell below its damage threshold. This combination of nonlinearities clamps the maximum encircled energy below 1 μ J for input energies up to 14.5 mJ at a 10 Hz repetition rate. This corresponds to a dynamic range of at least 7500 while it is possibly much greater since no damage occurred to any device components. Here we present details of the operation of this device.