bluuebunny/crossref_metadata_2025 huggingface dataset:
CROSS-BORDER TOURISM FROM BRUNEI DARUSSALAM TO EASTERN MALAYSIA: AN EMPIRICAL ANALYSIS
Authors: ANAMAN KWABENA A. , ISMAIL ROSE AMINAH
Published: September 2002

We analysed the factors influencing the level of cross-border tourism from Brunei Darussalam to Eastern Malaysia based on a random survey of 675 Bruneian residents returning from land and sea trips to Eastern Malaysia and using simple statistical and multiple regression analysis. The results revealed that the age of the respondents, personal income, perceived quality of Eastern Malaysia as a better place to rest and relax, perceived quality of goods and services in Eastern Malaysia, use of alcohol by respondents and having family members and friends living in Eastern Malaysia were significant factors affecting the number of visits to Eastern Malaysia. This analysis was based on visits over the 12-month period prior to the survey, a period of relative price stability. Regression analysis of personal expenditures on goods and services of respondents during their most recently completed trip indicated that personal income, travelling with friends, number of days spent on the trip, perception of Eastern Malaysia as a better place to rest and relax and use of public transport were the significant factors affecting expenditures. We estimated that Bruneian residents spent about B$426 million a year on goods and services while visiting Eastern Malaysia, and this amount accounted for roughly 5.7% of Brunei's gross domestic product (GDP) in the year 2000.
SINGAPORE'S EXCHANGE RATE POLICY: EMPIRICAL FOUNDATIONS, PAST PERFORMANCE AND OUTLOOK
Authors: YIP PAUL S. L.
Published: September 2002

Singapore's exchange rate policy in practice is a policy mix somewhat more complicated than the simple "strong Singapore dollar policy". This paper discusses the theoretical and empirical foundations of this policy mix. It then proceeds to evaluate the past performance of Singapore's exchange rate policy. By highlighting a drastic decline in foreign inflation towards a negligible level nowadays, the paper recommends a far more moderate appreciation of Singapore dollar than those in the past.
PRECAUTIONARY SAVINGS AND CPF CONTRIBUTIONS IN THE PRESENCE OF A BORROWING CONSTRAINT
Authors: LAM CHERN WOON , KAPUR BASANT K.
Published: September 2002

The neutrality result that total private savings (voluntary and compulsory) are invariant to a change in the employee's CPF contribution rate has been derived by Hoon (1991) and Liew (2000), both of whom assumed perfect capital markets. It was shown by Lim (1994) to hold in a model with borrowing constraints as long as the latter are nonbinding. In this article, we integrate the phenomena of income uncertainty (from Liew) and borrowing constraints (from Lim) in a stochastic, intertemporal optimisation model. We demonstrate the existence of precautionary savings and, contrary to received thinking, the nonneutrality result of total savings to the employee's CPF contribution rate even for workers with positive voluntary savings. The broader implications of this result are also discussed.
AN EVALUATION OF HEDGE FUNDS: RISK, RETURN AND PITFALLS
Authors: KOH FRANCIS , LEE DAVID K. C. , PHOON KOK FAI
Published: September 2002

Hedge funds are collective investment vehicles fast becoming popular with high net worth individuals as well as institutional investors. These are funds that are often established with a special legal status that allows their investment managers a free hand to use derivatives, short sell and exploit leverage to raise returns and cushion risk. Given that they have substantial latitude to invest, it is instructive to examine the performance of hedge funds as compared to other forms of managed funds. This paper provides an overview of hedge funds and discusses their empirical risk and return profiles. It also poses some concerns regarding the empirical measurements. Given the complexity of hedge fund investments, meaningful analytical methods are required to provide greater risk transparency and performance reporting. Hedge fund performance is also beset by a number of practical issues generating "practical risks". These risks are not fully addressed by the usual risk-adjusted performance measures in the literature. A penalty function to discount these extraneous risk dimensions is proposed. The paper concludes that further empirical work is required to provide informative statistics about the risk and return of hedge funds.
SOME ANALYSIS OF HADRON–NUCLEON COLLISIONS AT HIGH ENERGY INELASTIC INTERACTIONS IN PHOTO-EMULSION
Authors: ABD EL-HALIM S. M.
Published: September 2002

The interaction of 400 GeV/c protons and 340 GeV/c π- with nucleons in nuclear emulsion has been investigated. The interaction mean free paths (m.f.p.) and the corresponding reaction cross-sections (σ in ) have been found, the multiplicity distributions for the events with Nh = 0 (clean events) are measured and studied as well as the angular and pseudorapidity distributions. Finally the coherent multiparticle production cross-sections (σ coh ) were estimated and compared with other data, where it was found to be increasing slowly with increasing incident momentum for protons while it increases rapidly with increasing π--momentum.
SOLUTION TO WORLDVOLUME ACTION OF D3 BRANE IN pp-WAVE BACKGROUND
Authors: PAL SHESANSU SEKHAR
Published: September 2002

We find nonsupersymmetric and supersymmetric solutions of D3 brane configuration in the background of pp-wave obtained as a Penrose limit of AdS5 × S5.
DEGENERACY IN EXOTIC GRAVITATIONAL LENSING
Authors: SAFONOVA MARGARITA , TORRES DIEGO F.
Published: September 2002

We present three different theoretically foreseen, but unusual, astrophysical situations where the gravitational lens equation ends up being the same, thus producing a degeneracy problem. These situations are: (a) the case of gravitational lensing by exotic stresses (matter violating the weak energy condition and thus having a negative mass, particular cases of wormhole solutions can be used as an example), (b) scalar field gravitational lensing (i.e. when considering the appearance of a scalar charge in the lensing scenario), and (c) gravitational lensing in closed universes (with antipodes). The reasons that lead to this degeneracy in the lens equations, the possibility of actually encountering it in the real universe, and eventually the ways to break it, are discussed.
KLAUDER–PERELOMOV AND GAZEAU–KLAUDER COHERENT STATES FOR SOME SHAPE INVARIANT POTENTIALS
Authors: CHENAGHLOU A. , FAKHRI H.
Published: September 2002

Firstly, the solvability of some quantum models like Eckart and Rosen–Morse II are explained on the basis of the shape invariance theory. Then, two generalized types of the Klauder–Perelomov and Gazeau–Klauder coherent states are calculated for the models. By means of calculating the Mandel parameter, it is shown that the weight distribution function of the first type coherent states obeys the Poissonian and super-Poissonian statistics, however, the weight distribution function of the second type coherent states obeys the Poissonian and sub-Poissonian statistics.
ON THE NEUTRON BURSTS ORIGIN
Authors: STENKIN YURI V. , VALDÉS-GALICIA JOSÉ. F.
Published: September 2002

The origin of the neutron bursts in Extensive Air Showers (EAS) is explained using results of the experiments and CORSIKA based Mont–Carlo simulations. It is shown that events with very high neutron multiplicity observed last years in neutron monitors as well as in surrounding detectors, are caused by the usual EAS core with primary energies >1 PeV . No exotic processes were needed for the explanation.
POSITRONIUM PHYSICS BEYOND THE STANDARD MODEL
Authors: GNINENKO S. N. , KRASNIKOV N. V. , RUBBIA A.
Published: September 2002

Possible manifestations of new physics in rare (exotic) decays of orthopositronium (o - Ps) are briefly reviewed. It is pointed out that models with infinite additional dimension(s) of Randall–Sundrum type predict disappearance of orthopositronium into additional dimension(s). The experimental signature of this effect is the invisible decay of orthopositronium. We point out that this process may occur at a rate within two or three orders of magnitude of the present experimental upper limit. We also propose a model with a light weakly interacting boson leading to o - Ps → invisible decays at the experimentally interesting rate. We discuss this in details and stress that the existence of invisible decay of orthopositronium in vacuum could explain the o - Ps decay rate puzzle. Thus, our result enhances the existing motivation and justifies efforts for a more sensitive search for o - Ps → invisible decay in a near future experiment.
LEPTOGENESIS IN MODELS WITH MULTI-HIGGS BOSONS
Authors: FUKUYAMA TAKESHI , OKADA NOBUCHIKA
Published: September 2002

We study the leptogenesis scenario in models with multi-Higgs doublets. It is pointed out that the washing-out process through the effective dimension-five interactions, which has not been taken into account seriously in the conventional scenario, can be effective, and the resultant baryon asymmetry can be exponentially suppressed. This fact implies new possible scenario where the observed baryon asymmetry is the remnant of the washed out lepton asymmetry which was originally much larger than the one in the conventional scenario. Our new scenario is applicable to some neutrino mass matrix models which predict too large CP-violating parameter and makes them viable through the washing-out process.
ROLE OF THE ELECTRON–PHONON INTERACTION ON THE SPECTRAL DENSITY AND PSEUDOGAP IN CUPRATES
Authors: CHAUDHURI I. , GHATAK S. K.
Published: September 2002

The pseudogap structure in low energy excitation in cuprates appears below a temperature and the spectral density exhibits strong wave-vector dependence. An electronic model that emphasized the coupling of carrier in Cu-O with phonon is examined for pseudogap. The electron–phonon interaction originates from the modulation of on-site and hopping energy and leads to spontaneous Jahn–Teller-like distortion and pseudogap below a critical temperature. At low temperature the spectral density has two-peak structure about the Fermi level for all k along Γ-M whereas such structure exists along Γ-X for small k only. The magnitude of pseudogap shows strong k-dependence — maximum along Γ-M and vanishes along Γ-X. These features emphasize the role of electron–phonon interaction in formation of pseudogap.
THERMAL NOISE OF DC JOSEPHSON CURRENT IN A SUPERCONDUCTOR-QUANTUM-DOT-SUPERCONDUCTOR SYSTEM
Authors: ZHAO HONG-KANG
Published: September 2002

The thermal noise of DC Josephson current in the superconducting leads coupled with a quantum dot system is investigated, and the general thermal current noise formula is derived in the presence of Zeeman field. The resonant structure versus gate voltage and Zeeman energy are displayed. Novel structures associated with the bound state and normal energy state are obtained. As the temperature is low, the Andreev reflection plays an important role in thermal noise and this provides new channels for electron to tunnel. However, if the temperature is high enough, the thermal noise due to Andreev reflection is trivial compared with the normal transport one. The thermal noise versus phase difference is also given to exhibit the temperature dependence. The Fano factor versus phase is much larger than 1 if the temperature is nonzero.
CONSTRUCTION OF A DISPERSION RELATION FROM AN ARBITRARY DENSITY OF STATES
Authors: KOLLAR MARCUS
Published: September 2002

The dispersion relations of energy bands in solids are characterized by their density of states, but a given density of states may originate from various band structures. We show how a spherically symmetric dispersion can be constructed for any one-band density of states. This method is applied to one-, two- and three-dimensional systems. It also serves to establish that any one-band spectrum with finite bandwidth can be obtained from a properly scaled dispersion relation in the limit of infinite dimensions.
EXACT SOLUTION AT INTEGRABLE COUPLING OF A MODEL FOR THE JOSEPHSON EFFECT BETWEEN SMALL METALLIC GRAINS
Authors: LINKS JON , ZHOU HUAN-QIANG , MCKENZIE ROSS H. , GOULD MARK D.
Published: September 2002

A model is introduced for two reduced BCS systems which are coupled through the transfer of Cooper pairs between the systems. The model may thus be used in the analysis of the Josephson effect arising from pair tunneling between two strongly coupled small metallic grains. At a particular coupling strength the model is integrable and explicit results are derived for the energy spectrum, conserved operators, integrals of motion, and wave function scalar products. It is also shown that form factors can be obtained for the calculation of correlation functions. Furthermore, a connection with perturbed conformal field theory is made.
DETERMINATION OF DIFFUSION PARAMETERS OF CO2 THROUGH MICROPOROUS PTFE USING A POTENTIOMETRIC METHOD
Authors: TARSICHE I. , CIURCHEA D.
Published: September 2002

Dk values at the diffusion of CO 2 through microporous PTFE of 1 to 7 × 10-7 cm 2 s -1 in the concentration range from 4 × 10-4 to 0.22 g/l CO 2 are determined using a simple, fast and reliable potentiometric method. The method is based on the least-squares fitting of the potential versus time response of a self made CO 2 sensitive Severinghaus type sensor with PTFE as a gas-permeable membrane. The obtained results are in good agreement with other reported literature data, both experimental or calculated ones using molecular dynamics simulations. The proposed technique is very sensitive especially at low concentrations of gas and may be used for the study of other polymeric membranes too.
REVISITING DENSITY OF STATE CALCULATIONS FOR THE HARPER-EQUATION
Authors: PAPP E. , MICU C. , SZAKACS Zs.
Published: September 2002

Density of state calculation performed previously for the Harper-equation by Wannier, Obermair and Ray [Phys. Status SolidiB93, 337 (1979)] are updated analytically and numerically. One considers both the influence of anisotropy and commensurability parameters. The main point of our generalization is to account for a multiplicity parameter describing the amount of coprime realizations of the commensurability parameter.
A DIAGRAMMATIC APPROACH TO STUDY THE INFORMATION TRANSFER IN WEAKLY NONLINEAR CHANNELS
Authors: KORUTCHEVA E. , DEL PRETE VALERIA
Published: September 2002

In a recent work we have introduced a novel approach to study the effect of weak nonlinearity in the transfer function on the information transmitted by an analogue channel, by means of a perturbative diagrammatic expansion. We extend here the analysis to all orders in perturbation theory, which allows us to release any constraint concerning the magnitude of the expansion parameter and to establish the rules to calculate easily the contribution at any order. As an example we explicitly compute the information up to the second order in nonlinearity, in presence of random Gaussian connectivity and in the limit when the output noise is not small. We analyze the first and second order contributions to the mutual information as a function of the nonlinearity and as a function of the number of output units. We believe that an extensive application of our method via the analysis of the different contributions at distinct orders might be able to fill a gap between well-known analytical results obtained for linear channels and nontrivial treatments which are required to study highly nonlinear channels.
THE EFFECT OF FILM THICKNESS ON THE MICROSTRUCTURE OF La0.5Ca0.5MnO3 FILMS
Authors: CHEN X. M. , WANG Y. , LIU C. X. , ZHAO Y. N. , MAI Z. H. , GONG W. Z. , ZHAO B. R. , JIA C. J. , ZHENG W. L.
Published: September 2002

La 0.5 Ca 0.5 MnO 3 (LCMO) thin films grown on SrTiO 3 substrate with different thickness were investigated using high resolution X-ray diffraction, small angle reflectivity, and atomic force microscope (AFM). All the films are demonstrated to be c-axis oriented. The surface and interface structure of the films were obtained. It was found that the surface morphology of the films strongly depends on the thickness, and the film will crack when the thickness of the film reach a critical thickness. The surface roughness of the films increases with the thickness. The interface between the films and the substrates are very clear. There exists a non-designed cap layer on the surface of the LCMO layer.
NEW LYOTROPIC LIQUID CRYSTALS BASED ON SURFACTANTS
Authors: HONCIUC MARIA , BORLESCU C. , POPA CARMEN
Published: September 2002

We presented here the phase diagrams and the influence of the external electric field on the lyotropic liquid crystal phase (LLC) for some binary and pseudoternary systems based on surfactants. Binary systems are of the type surfactant/water (S/W) and the pseudoternary systems are of the type surfactant/oil/water (S/O/W). Two surfactants have been used: the lauryl alcohol ethoxilated with 11 molecules of ethylene oxide (LA11EO), which is a nonionic compound, and a mixture of LA11EO with the cationic surfactant named alkyl C12– C14-dimethyl-benzyl ammonium chloride. Based on these two types of surfactants, pseudoternary systems were prepared. Pine oil has been used as the oil. The region where the LLC phase appears depends on the concentration of the surfactant and that of the pine oil, respectively. It is strongly influenced by the nature of the surfactant and by the presence of the pine oil for the same type of surfactant. The influence of the external electric field, investigated by measuring the electric current appearing in the samples for different concentrations of surfactant and pine oil was found to be more important in the case of the systems based on the nonionic-cationic mixture of surfactants. The results are discussed in terms of a theoretical model based on the local thermal equilibrium approach for systems running nonstatic processes.
STRUCTURE MAPS FOR POLYMER STRUCTURES
Authors: HAUCK J. , ERKENS W. , MIKA K. , WINGERATH K.
Published: September 2002

One-, two- and three-dimensional structures A x B y can be characterized by the numbers T1, T2 and T3 of the nearest, next-nearest and third neighbors of the same kind. A smaller number of structures at the border of the T1, T2, T3 structure map is stabilized by enthalpy compared to an increased number of entropy stabilized structures away from the border. Structures with T1 = 2 nearest neighbors of all A atoms are suitable for infinite chains of polymers like (CH) ∞, ( CHCH 2)∞ or ( CH 2)∞.
PROPERTIES OF GADOLINIUM-DOPED PZT (Zr:Ti=52:48)
Authors: BOONYUEN S. , PDUNGSAP L. , WINOTAI P. , SUDYOADSUK T. , PETCHPONG P.
Published: September 2002

PZT(Zr:Ti=52:48) ceramics can be modified by Gd 3+, giving compositions Pb 1-x Gd x- ( Zr 0.52 Ti 0.48)1-x/4 O 3 with x = 0.00, 0.01, 0.5, 1, 2, 6 and 10 mole percent. X-ray diffraction patterns show that all PGZT samples are of tetragonal structure and the highest doping should be no more than 2 mole percent Gd at which impurity unreacted oxides start to appear. ESR spectra of PGZT's indicate that Gd 3+ can enter both A and B sites of the perovskite structure instead of only A site as widely believed. As a result, the tetragonality (c/a ratio) first increases and reaches a maximum at x ≅ 0.8 mole percent and drops as Gd 3+ enters more A sites. The doping should, however be limited to one mole percent as overdoping proves detrimental to the dielectric and piezoelectric properties of PGZT. The dielectric constant (1 kHz) of the poled samples reaches a maximum value of 1150 at x = 0.02 while the largest d33 value of 160 pC/N is achieved at only lightly doped 0.01 mole percent. Furthermore, the Gd doping has a drastic effect on Qm and the dissipation factor DF — the former drops sharply while the latter increases with x.
PRELIMINARY NMR AND ESR INVESTIGATION OF LOCAL DYNAMICS IN SOME POLYISOPRENE-CCl4 SOLUTIONS
Authors: TODICA M.
Published: September 2002

The temperature dependence of the NMR spin-lattice relaxation time is analyzed for preliminary evaluation of the correlation time of the local dynamics of the polymeric chain, for the molten polyisoprene and some polyisoprene- CCl 4 solutions. Complementary information concerning this dynamics were obtained from the analyze of the ESR spectra recorded from the nitroxide molecules (2, 2, 6, 6, tetramethyl piperidin-1-yloxyl) dissolved in the polyisoprene- CCl 4 solutions.
THE THICKNESS DEPENDENT STRUCTURE OF COPPER PHTHALOCYANINE FILMS
Authors: OHMUKAI MASATO , UOZUMI TOYOICHI , TAKIMOTO KOJI , TSUTSUMI YASUO
Published: September 2002

We deposited copper phthalocyanine (CuPc) films on (100) silicon wafers by means of a vacuum evaporation method and investigated the dependence of X-ray diffraction pattern on film thickness. We concluded that the planar molecule of CuPc is stacked normal to the substrate within 700 nm from an interface. Above 700 nm, four types of nearly parallel stacking were also observed. These results show the spontaneous formation of the two-layer structure in CuPc films thicker than 700 nm.
MULTIBAND SUPERCONDUCTIVITY
Authors: NAGAO HIDEMI , KRUCHININ SERGEI P. , YAREMKO ANATOLI M. , YAMAGUCHI KIZASHI
Published: September 2002

Multi-band superconductivity is investigated by using two-particle Green's function techniques, and equations for coupled states are derived in the framework of a two-band model. These results suggest that superconductivity appears, even if electron–electron interaction is positive. We also present a cooperative mechanism for multi-band superconductivity.
INCONSISTENT REQUIREMENTS: AN ARGUMENTATION VIEW
Authors: PERRUSSEL LAURENT , CHARREL PIERRE-JEAN
Published: September 2002

In this article, we present a logical framework for reasoning about inconsistent requirements in the context of multi-viewpoint requirements engineering process. In order to analyse the sources of inconsistencies and to reason with inconsistent requirements, we present an argumentation view of the requirements. Intuitively, argumentation is a tool for reasoning with inconsistent knowledge: requirements are defined in terms of arguments (a conclusion with its support); then, a class of acceptable arguments is built (arguments with no counter arguments).

We suggest to characterize different classes of requirements ordered in the following way: from weakly confident to strongly confident (i.e. consistent). In the paper, we present inference rules to build intra and inter-viewpoint reasoning. Inference rules stem from the classes of requirements. We show how this work is useful for the requirements engineers in analysing inconsistent fragments of requirements.
A DECENTRALIZED MODEL-BASED DIAGNOSTIC TOOL FOR COMPLEX SYSTEMS
Authors: PENCOLÉ Y. , CORDIER M.-O. , ROZÉ L.
Published: September 2002

We address the problem of diagnosing complex discrete-event systems such as telecommunication networks. Given a flow of observations from the system, the goal is to explain those observations by identifying and localizing possible faults. Several model-based diagnosis approaches deal with this problem but they need the computation of a global model which is not feasible for complex systems like telecommunication networks. Our contribution is the proposal of a decentralized approach which permits to carry out an on-line diagnosis without computing the global model. This paper describes the implementation of a tool based on this approach. Given a decentralized model of the system and a flow of observations, the program analyzes the flow and computes the diagnosis in a decentralized way. The impact of the merging strategy on the global efficiency is demonstrated and illustrated by experimental results on a real application.
TOWARDS A GENERAL THEORY FOR MODELLING QUALITATIVE SPACE
Authors: EL-GERESY BAHER A. , ABDELMOTY ALIA I.
Published: September 2002

Qualitative spatial representation and reasoning are techniques for modeling and manipulating objects and relationships in space. Finding ways for defining the complete and sound (physically plausible) set of relationships between spatial objects is a prerequisite for the development and realization of qualitative representation and reasoning formalisms. Establishing the set of sound relationships is a complicated task especially when complex objects are considered. Hence, current approaches to qualitative representation and reasoning are limited to handling simple spatial objects. In this paper, we introduce a constraint-based approach to qualitative representation of topological relationships by defining a set of general soundness rules. The rules reduce the combinatorial set of relations produced by the method to the complete and physically possible ones. The rules are general and apply to objects of arbitrary complexity and together with the representation and reasoning formalism form a theory for qualitative space.
B-COURSE: A WEB-BASED TOOL FOR BAYESIAN AND CAUSAL DATA ANALYSIS
Authors: MYLLYMÄKI PETRI , SILANDER TOMI , TIRRI HENRY , URONEN PEKKA
Published: September 2002

B-Course is a free web-based online data analysis tool, which allows the users to analyze their data for multivariate probabilistic dependencies. These dependencies are represented as Bayesian network models. In addition to this, B-Course also offers facilities for inferring certain type of causal dependencies from the data. The software uses a novel "tutorial stylerdquo; user-friendly interface which intertwines the steps in the data analysis with support material that gives an informal introduction to the Bayesian approach adopted. Although the analysis methods, modeling assumptions and restrictions are totally transparent to the user, this transparency is not achieved at the expense of analysis power: with the restrictions stated in the support material, B-Course is a powerful analysis tool exploiting several theoretically elaborate results developed recently in the fields of Bayesian and causal modeling. B-Course can be used with most web-browsers (even Lynx), and the facilities include features such as automatic missing data handling and discretization, a flexible graphical interface for probabilistic inference on the constructed Bayesian network models (for Java enabled browsers), automatic prettyHyphen;printed layout for the networks, exportation of the models, and analysis of the importance of the derived dependencies. In this paper we discuss both the theoretical design principles underlying the B-Course tool, and the pragmatic methods adopted in the implementation of the software.
INTELLIGENT NLP-DRIVEN TEXT CLASSIFICATION
Authors: BASILI ROBERTO , MOSCHITTI ALESSANDRO
Published: September 2002

Information Retrieval (IR) and NLP-driven Information Extraction (IE) are complementary activities. IR helps in locating specific documents within a huge search space (localization) while IE supports the localization of specific information within a document (extraction or explanation). In application scenarios both capabilities are usually needed. IE is important here, as it can enrich the IR inferences with motivating information. Works on Web-based IR suggest that embedding linguistic information (e.g. sense distinctions) at a suitable level within traditional quantitative approaches (e.g. query expansion as in [26]) is a promising approach. "Which linguistic level is best suited to which IR mechanism" is the interesting representational problem posed by the current research stage. This is also the central concern of this paper. A traditional method for efficient text categorization is here presented. Original features of the proposed model are a self-adapting parameterized weighting model and the use of linguistic information. The key idea is the integration of NLP methods within a robust and efficient TC framework. This allows to combine benefits of large scale and efficient IR with the richer expressivity closer to IE. In this paper we capitalize the systematic benchmarking resources available in TC to extensively derive empirical evidence about the above representational problem. The positive experimental results confirm that the proposed TC framework characterizes as a viable approach to intelligent text categorization on a large scale.
SUCCESSIVE SEARCH METHOD FOR SOLVING VALUED CONSTRAINT SATISFACTION AND OPTIMIZATION PROBLEMS
Authors: TOUNSI MOHAMED , DAVID PHILIPPE
Published: September 2002

In this paper we introduce a new method based on Russian Doll Search (RDS) for solving optimization problems expressed as Valued Constraint Satisfaction Problems (VCSPs). The RDS method solves problems of size n (where n is the number of variables) by replacing one search by n successive searches on nested subproblems using the results of each search to produce a better lower bound. The main idea of our method is to introduce the variables through the successive searches not one by one but by sets of k variables. We present two variants of our method: the first one where the number k is fixed, noted kfRDS; the second one, kvRDS, where k can be variable. Finally, we show that our method improves RDS on daily management of an earth observation satellite.
HIGH PERFORMANCE LOGIC FORM TRANSFORMATION
Authors: RUS VASILE , MOLDOVAN DAN I.
Published: September 2002

This paper presents extensions to a previously developed logic form representation and a method for transforming WordNet glosses into logic forms using a set of high-precision rules combined with a set of high recall heuristics. An almost 3% increase in POS tagging accuracy is achieved over state-of-the art results at the expense of user intervention on only 7.52% of words. We apply a nearest neighbor solution of parser switching that leads to 6.43% increase in exact sentence accuracy for glosses. Logic Forms are derived with an accuracy of 89.46%.
PICKUP AND DELIVERY WITH TIME WINDOWS: ALGORITHMS AND TEST CASE GENERATION
Authors: LAU HOONG CHUIN , LIANG ZHE
Published: September 2002

In the pickup and delivery problem with time windows (PDPTW), vehicles have to transport loads from origins to destinations respecting capacity and time constraints. In this paper, we present a two-phase method to solve the PDPTW. In the first phase, we apply a novel construction heuristics to generate an initial solution. In the second phase, a tabu search method is proposed to improve the solution. Another contribution of this paper is a strategy to generate good problem instances and benchmarking solutions for PDPTW, based on Solomon's benchmark test cases for VRPTW. Experimental results show that our approach yields very good solutions when compared with the benchmarking solutions.
GENERALIZED COMONOTONICALLY ADDITIVE OPERATORS: REPRESENTATIONS BY CHOQUET INTEGRALS
Authors: SKALA HEINZ J.
Published: September 2002

Operators which behave (sub-, super-) additive on comonotonic functions occur quite naturally in many contexts, e.g. in decision theory, artificial intelligence, and fuzzy set theory. In the present paper we define comonotonicity for Riesz spaces with the principal projection property and obtain integral representations (in terms of Bochner integrals) for comonotonically additive operators acting on Riesz with the principal projection property and taking values in certain Riesz- or Banach spaces. As easy corollaries we obtain essential generalizations of representation theorems à la schmeidler, Proc. Am. Math. Soc. 97 (1986), 255 – 261. The existence of the necessary convergence theorems makes it possible to extend our results to set-valued operators. This is the topic of a further paper.
A FUZZY RISK MODEL AND ITS MATRIX ALGORITHM
Authors: HUANG CHONGFU , MORAGA CLAUDIO
Published: September 2002

In this paper, we introduce the interior-outer-set model for calculating a fuzzy risk represented by a possibility-probability distribution. The model involving combination calculus is very difficult to follow. In this paper, we transform it into a matrix algorithm. Although the algorithm is still difficult to follow, fortunately, it is easy to make a computer program for realizing. This algorithm consists of MOVING-subalgorithm and INDEX-subalgorithm. The former works out leaving and joining matrices. The latter is a combination algorithm to get index sets. An example is presented showing how a user can calculate a risk of strong earthquake with the algorithm.
SUM NORMAL OPTIMIZATION OF FUZZY MEMBERSHIP FUNCTIONS
Authors: SIMON DAN
Published: September 2002

Given a fuzzy logic system, how can we determine the membership functions that will result in the best performance? If we constrain the membership functions to a certain shape (e.g., triangles or trapezoids) then each membership function can be parameterized by a small number of variables and the membership optimization problem can be reduced to a parameter optimization problem. This is the approach that is typically taken, but it results in membership functions that are not (in general) sum normal. That is, the resulting membership function values do not add up to one at each point in the domain. This optimization approach is modified in this paper so that the resulting membership functions are sum normal. Sum normality is desirable not only for its intuitive appeal but also for computational reasons in the real time implementation of fuzzy logic systems. The sum normal constraint is applied in this paper to both gradient descent optimization and Kalman filter optimization of fuzzy membership functions. The methods are illustrated on a fuzzy automotive cruise controller.
FUZZY MULTIOBJECTIVE PROGRAMMING METHODS FOR FUZZY CONSTRAINED MATRIX GAMES WITH FUZZY NUMBERS
Authors: LI DENGFENG , CHENG CHUNTIAN
Published: September 2002

The purpose of the paper is to introduce a new type of fuzzy matrix games: fuzzy constrained matrix games. A computational method for its solution based on establishment of the auxiliary fuzzy linear programming for each player is proposed. The approach based on the multiobjective programming is establisched to solve these fuzzy linear programming. Effectiveness is illustrated with a numerical example.
A HYBRID MODEL FOR SHARING INFORMATION BETWEEN FUZZY, UNCERTAIN AND DEFAULT REASONING MODELS IN MULTI-AGENT SYSTEMS
Authors: LUO XUDONG , ZHANG CHENGQI , JENNINGS NICHOLAS R.
Published: September 2002

This paper develops a hybrid model which provides a unified framework for the following four kinds of reasoning: 1) Zadeh's fuzzy approximate reasoning; 2) truth-qualification uncertain reasoning with respect to fuzzy propositions; 3) fuzzy default reasoning (proposed, in this paper, as an extension of Reiter's default reasoning); and 4) truth-qualification uncertain default reasoning associated with fuzzy statements (developed in this paper to enrich fuzzy default reasoning with uncertain information). Our hybrid model has the following characteristics: 1) basic uncertainty is estimated in terms of words or phrases in natural language and basic propositions are fuzzy; 2) uncertainty, linguistically expressed, can be handled in default reasoning; and 3) the four kinds of reasoning models mentioned above and their combination models will be the special cases of our hybrid model. Moreover, our model allows the reasoning to be performed in the case in which the information is fuzzy, uncertain and partial. More importantly, the problems of sharing the information among heterogeneous fuzzy, uncertain and default reasoning models can be solved efficiently by using our model. Given this, our framework can be used as a basis for information sharing and exchange in knowledge-based multi-agent systems for practical applications such as automated group negotiations. Actually, to build such a foundation is the motivation of this paper.
PSEUDO-CONVOLUTION BASED ON IDEMPOTENT OPERATION AS LIMIT OF g-CONVOLUTION
Authors: PAP ENDRE , ŠTAJNER IVANA
Published: September 2002

Operation with functions known as pseudo-convolution and its generalization as well as theirs basic properties has been presented. Then, it has been proved that pseudo-convolution which core is pseudo-integral based on max or min decomposable measure can be obtained as limit of g-convolutions, i.e., pseudo-convolutions with pseudo-integrals based on ⊕-decomposable measures where ⊕ is generated pseudo-addition, as their cores.
STRUCTURAL AND ELECTRONIC PROPERTIES OF AL NANOWIRES: AN AB INITIO PSEUDOPOTENTIAL STUDY
Authors: ZHENG JIN-CHENG , WANG HUI-QIONG , WEE A. T. S. , HUAN C. H. A.
Published: September 2002

The stability and electronic structure of a single monatomic Al wire has been studied using the ab initio pseudopotential method. The Al wire undergoes two structural rearrangements under compression, i.e., zigzag configurations at angles of 140° and 60°. The evolution of electronic structures of the Al chain as a function of structural phase transition has been investigated. The relationship between electronic structure and geometric stability is also discussed. The 2p bands in the Al nanowire are shown to play a critical role in its stability. The effects of density functionals (GGA and LDA) on cohesive energy and bond length of Al nanostructures (dimer, chains, and monolayers) are also examined. The link between low dimensional 0D structure (dimer) to high dimensional 3D bulk Al is estimated. An example of optimized tip-suspended finite atomic chain is presented to bridge the gap between hypothetical infinite chains and experimental finite chains.
Powder X-ray diffraction data for goosecreekite [CaAl2Si6O16⋅5H2O]
Authors: Raade Gunnar , Berg Hans-Jørgen
Published: September 2002

X-ray powder data originally published for the zeolite mineral goosecreekite are of poor quality. The new data reported here for material from Norway are compared with powder data calculated from the published structure. The cell is monoclinic (space group P21, Z=2), a=7.422(2) Å, b=17.414(4) Å, c=7.288(2) Å, β=105.43(3)°, V=907.9(3) Å3. F30=32.75(0.023,40).
Shift of bifurcation point due to noise induced parameter
Authors: Banerjee Sandip , Bhattacharya Rakhi , Chakrabarti C. G.
Published: September 2002

The object of the paper is to see the effect of small stochastic
parametric perturbation on a nonlinear interacting system
exhibiting Hopf bifurcation. The method is based on the technique
of Markov diffusion approximation.
Cauchy′s interlace theorem and lower bounds for the spectral radius
Authors: Mercer A. McD. , Mercer Peter R.
Published: September 2002

We present a short and simple proof of the well‐known Cauchy
interlace theorem. We use the theorem to improve some lower bound
estimates for the spectral radius of a real symmetric matrix.
MHD flow of an elastico‐viscous fluid under periodic body acceleration
Authors: El-Shehawey E. F. , Elbarbary Elsayed M. E. , Afifi N. A. S. , Elshahed Mostafa
Published: September 2002

Magnetohydrodynamic (MHD) flow of blood has been studied under the influence of body acceleration. With the help of Laplace and finite
Hankel transforms, an exact solution is obtained for the unsteady
flow of blood as an electrical conducting, incompressible and
elastico‐viscous fluid in the presence of a magnetic field acting
along the radius of the pipe. Analytical expressions for axial
velocity, fluid acceleration and flow rate has been obtained.
On the system of two nonlinear difference equations xn+1 = A + xn−1/yn,    yn+1 = A + yn−1/xn
Authors: Papaschinopoulos G. , Schinas C. J.
Published: September 2002

We study the oscillatory behavior, the periodicity and the
asymptotic behavior of the positive solutions of the system of two
nonlinear difference equations xn+1 = A + xn−1/yn and yn+1 = A + yn−1/xn, where A is a
positive constant, and n = 0, 1, ….
Stability of second‐order recurrences modulo pr
Authors: Somer Lawrence , Carlip Walter
Published: September 2002

The concept of sequence stability generalizes the idea of uniform distribution. A sequence is p‐stable if the set of residue frequencies of the sequence reduced modulo pr is eventually constant as a function of r. The authors identify and characterize the stability of second‐order recurrences modulo odd primes.
New inversion formulas for the Krätzel transformation
Authors: Cruz-Báez Domingo Israel , Expósito José Rodríguez
Published: September 2002

We study in distributional sense by means of the kernel method an
integral transform introduced by Krätzel. It is well known
that the cited transform generalizes to the Laplace and Meijer
transformation. Properties of analyticity, boundedness, and
inversion theorems are established for the generalized
transformation.
Analogues of some Tauberian theorems for stretchings
Authors: Patterson Richard F.
Published: September 2002

We investigate the effect of four‐dimensional matrix transformation on new classes of double sequences. Stretchings of a double sequence is defined, and this definition is used to
present a four‐dimensional analogue of D. Dawson′s copy theorem for stretching of a double sequence. In addition, the multidimensional analogue of D. Dawson′s copy theorem is used to
characterize convergent double sequences using stretchings.
On the stability of the quadratic mapping in normed spaces
Authors: Kim Gwang Hui
Published: September 2002

The Hyers‐Ulam stability, the Hyers‐Ulam‐Rassias stability, and
also the stability in the spirit of Gavruţa for each of
the following quadratic functional equations f(x + y) + f(x − y) = 2f(x) + 2f(y), f(x + y + z) + f(x − y) + f(y − z) + f(z − x) = 3f(x) + 3f(y) + 3f(z), f(x + y + z) + f(x) + f(y) + f(z) = f(x + y) + f(y + z) + f(z + x) are investigated.
Properties of the function f(x) = x/π(x)
Authors: Vlamos Panayiotis
Published: September 2002

We obtain the asymptotic estimations for and , where f(k) = k/π(k), k ≥ 2. We study the expression 2f(x + y) − f(x) − f(y) for integers x, y ≥ 2 and
as an application we make several remarks in connection with the
conjecture of Hardy and Littlewood.
On zero subrings and periodic subrings
Authors: Bell Howard E.
Published: September 2002

We give new proofs of two theorems on rings in which
every zero subring is finite; and we apply these
theorems to obtain a necessary and sufficient condition
for an infinite ring with periodic additive group to
have an infinite periodic subring.
Asymptotic decay of nonoscillatory solutions of general nonlinear difference equations
Authors: Thandapani E. , Marian S. Lourdu , Graef John R.
Published: September 2002

The authors consider the mth order nonlinear difference
equations of the form Dmyn + qnf(yσ(n)) = ei, where
m ≥ 1, n ∈ ℕ = {0, 1, 2, …}, for
i = 1, 2, …, m − 1, , D0yn = yn, , i = 1, 2, …, m, σ(n) → ∞ as n → ∞, and f : ℝ → ℝ is continuous with uf(u) > 0 for u ≠ 0. They give sufficient conditions to
ensure that all bounded nonoscillatory solutions tend to zero as
n → ∞ without assuming that , i = 1, 2, …, m − 1, {qn} is positive, or en ≡ 0 as is often required. If {qn} is positive, they prove another such result for all
nonoscillatory solutions.
The Boolean algebra and central Galois algebras
Authors: Szeto George , Xue Lianyong
Published: September 2002

Let B be a Galois algebra with Galois group G, Jg = {b ∈ B | bx = g(x)b   for all   x ∈ B} for g ∈ G, and BJg = Beg for a central idempotent eg. Then a relation is given between the set of elements in the Boolean algebra (Ba, ≤) generated by {0, eg | g ∈ G} and a set of subgroups of G, and a central Galois algebra Be with a Galois subgroup of G is characterized for an e ∈ Ba.
Time series modelling of the Kobe‐Osaka earthquake recordings
Authors: Singh N. , Tampubolon D. , Yadavalli V. S. S.
Published: September 2002

A problem of great interest in monitoring a nuclear test ban treaty (NTBT) is related to interpreting properly the differences between a waveform generated by a nuclear explosion and that
generated by an earthquake. With a view of comparing these two types of waveforms, Singh (1992) developed a technique for identifying a model in time domain. Fortunately this technique has been found useful in modelling the recordings of the killer earthquake occurred in the Kobe‐Osaka region of Japan at 5.46 am on 17 January, 1995. The aim of the present study is to show how well the method for identifying a model (developed by Singh (1992)) can be used for describing the vibrations of the above mentioned earthquake recorded at Charters Towers in Queensland, Australia.
Spectral integration and spectral theory for non‐Archimedean Banach spaces
Authors: Ludkovsky S. , Diarra B.
Published: September 2002

Banach algebras over arbitrary complete non‐Archimedean fields are considered such that operators may be nonanalytic. There are
different types of Banach spaces over non‐Archimedean
fields. We have determined the spectrum of some closed commutative
subalgebras of the Banach algebra ℒ(E) of the continuous linear operators on a free Banach space E generated by projectors. We investigate the spectral integration of non‐Archimedean Banach algebras. We define a spectral measure and prove several properties. We prove the non‐Archimedean analog of
Stone theorem. It also contains the case of C‐algebras C∞(X, 𝕂). We prove a particular case of a representation of a C‐algebra with the help of a ‐projection‐valued measure. We consider spectral
theorems for operators and families of commuting linear continuous
operators on the non‐Archimedean Banach space.
On numerically effective log canonical divisors
Authors: Fukuda Shigetaka
Published: September 2002

Let (X, Δ) be a 4‐dimensional log variety which is proper over the field of complex numbers and with only divisorial log terminal singularities. The log canonical divisor KX + Δ is semiample, if it is numerically effective (NEF) and the Iitaka dimension κ(X, KX + Δ) is strictly positive. For the proof, we use Fujino′s abundance theorem for semi‐log canonical threefolds.
Sequences and series involving the sequence of composite numbers
Authors: Vlamos Panayiotis
Published: September 2002

Denoting by pn and cn the nth prime number and the nth composite number, respectively, we prove that both the sequence , defined by , and the series are convergent.
Hardy‐Littlewood type inequalities for Laguerre series
Authors: Lin Chin-Cheng , Lin Shu-Huey
Published: September 2002

Let {cj} be a null sequence of bounded variation. We give appreciate smoothness and growth conditions on {cj} to obtain the pointwise convergence as well as Lr‐convergence of Laguerre series . Then, we prove a Hardy‐Littlewood type inequality for certain r ≤ 1, where f is the limit function of . Moreover, we show that if is in Lr, r ≥ 1, we have the converse Hardy‐Littlewood type inequality for r ≥ 1 and β < −r/2.
Some theorems of random operator equations
Authors: Chuanxi Zhu , Zongben Xu
Published: September 2002

We investigate a class of random operator equations, generalize a famous theorem, and obtain some new results.
On new generalizations of Hardy′s integral inequalities
Authors: Zhongxue Lü , Hongzheng Xie
Published: September 2002

We give some new generalizations of Hardy′s integral inequalities.
Monopole harmonics for a special gauge
Authors: Uy Zenaida E. S.
Published: September 2002

The monopole harmonics for a special gauge are derived and found to differ from the Wu‐Yang monopole harmonics by a factor of eiqγcosθ, where γ is a real parameter.
p‐integrable selectors of multimeasures
Authors: Aló Richard , de Korvin Andre , Roberts Charles E.
Published: September 2002

The present work is a study of multivalued functions and measures which have many applications to mathematical economics and control problems. Both have received considerable attention in recent years. We study the set of selectors of the space of all p‐ integrable, X‐ valued additive set functions. This space contains an isometrically imbedded copy of Lp(X).
On the Alexander polynominals of alternating two‐component links
Authors: Kidwell Mark E.
Published: September 2002

Let L be an alternating two‐component link with Alexander polynomial Δ(x, y). Then the polynomials (1 − x)Δ(x, y) and (1 − y)Δ(x, y) are alternating. That is, (1 − y)Δ(x, y) can be written as in such a way that (−1) i+jcij ≥ 0.
Compactifications of convergens spaces
Authors: Kent D. C. , Richardson G. D.
Published: September 2002

This paper summarizes most of the results to date on convergence space
compactifications, and establishes necessary and sufficient conditions for the existence of largest and smallest compactifications subject to various conditions imposed upon the compactifications.