bluuebunny/crossref_metadata_2025 huggingface dataset:
SUSY SUPERPOTENTIALS FOR A CONFINED HULTHÉN POTENTIAL
Authors: VARSHNI Y. P.
Published: November 2004

A system consisting of an ion and an electron interacting through the Hulthén potential confined in an impenetrable spherical box, with the ion at the centre is considered. Superpotential which is the crucial quantity in supersymmetric quantum mechanics is proposed for the 1s and 2p states. Variational wave functions are thence derived. Energies are calculated from these for different values of the radius of box (R) and these are compared to the exact values; good agreement is shown to exist between the two. The variational wave functions are further employed to calculate the absorption oscillator strength for the 1s→2p transition and the dipole polarizability for different values of R.
SPIKES, ANOMALOUS EVENTS AND THE DIMENSIONAL STRUCTURE OF MULTIPARTICLE FLUCTUATIONS
Authors: BRAX PH. , PESCHANSKI R.
Published: November 2004

Random-cascading models are used to describe intermittency patterns of multiparticle events in high-energy reactions. The effect of projecting D-dimensional cascades onto D – 1 dimensions is tackled. It leads to a nontrivial dimensional classification of projected events into three groups: bulk-intermittent events, spikes corresponding to a D-dimensional phase transition and eventually anomalous events related to sheer (D – 1)-dimensional patterns. Applications to e+−e− and h - h reactions are envisaged using the Levy-stable-law intermittency parametrization.
MULTI-HIGGS SYSTEMS IN BOSONIC TECHNICOLOR: A MODEL FOR SSC PHYSICS
Authors: KAGAN ALEX , SAMUEL STUART
Published: November 2004

Multi-Higgs systems are combined with bosonic technicolor to construct a viable model of TeV physics. In such models, there is potentially a flavor problem in either the supersymmetric or the Higgs sector. However, the naturally larger mass scale for supersymmetry breaking and Higgs masses, which is a salient feature of bosonic technicolor, allows one to resolve the GUT-hierarchy problem without large flavor violation. With a judicious choice of the Higgs system, hierarchies of family masses and mixing angles of the right order of magnitude are achieved without resorting to small Yukawa couplings. Some of these masses and mixing angles are generated by radiative corrections. At energies below 100 GeV the standard model is reproduced, whereas at TeV energies a rich phenomenology of supersymmetric states and techni-hadrons is predicted. We present precise formulas to describe many aspects of the model and its phenomenology at tree and one-loop levels.
MULTIPLICITY AND PSEUDORAPIDITY DISTRIBUTIONS IN He-NUCLEUS INTERACTIONS AT ULTRARELATIVISTIC ENERGY
Authors: JAIN P.L. , SINGH G. , SENGUPTA K. , KIM S.N.
Published: November 2004

From the peripheral collisions of a 32 S beam at 200A GeV in nuclear emulsion, He tracks among the projectile fragments are identified and are followed for their interactions. The multiplicity distributions and their fluctuations in pseudorapidity intervals of the shower particles produced with ~500 He interactions in emulsions are compared with 32 S and 16 O beams at 200A GeV and 16 O at 60A GeV interactions. It is primarily the geometry of the nuclear collisions that determines the shape of different distributions.
QUASIELASTIC ELECTRON SCATTERING AND THE MODIFICATION OF MESONIC MASS PARAMETERS IN NUCLEI
Authors: BARRIOS S. CRUZ , CELENZA L.S. , GAO S.-F. , PANTZIRIS A. , SHAKIN C.M.
Published: November 2004

Making use of a vector-dominance model for the nucleon electromagnetic form factors, we investigate the consequences for the calculation of the inclusive electromagnetic response (in the quasielastic domain) of recent suggestions that mesonic mass parameters are modified in a nuclear medium.
17 keV NEUTRINO AND MAJORON MODELS
Authors: JOSHIPURA ANJAN S.
Published: November 2004

A model for the 17 keV Dirac neutrino is considered in the framework of the SU(2) × U(1) theory. No right-handed neutrinos are introduced. The Dirac mass for the neutrino arises from the Le+Lτ–Lμ invariant couplings of the left-handed neutrinos to an SU(2) triplet. An SU(2) singlet field is introduced to suppress the Majoron coupling to the Z. This makes the model consistent with the LEP results on the invisible Z width. The singlet vacuum expectation value ω is constrained to be ≤O(80 MeV) from cosmological considerations. For, ω≈80 MeV, the 17 keV neutrino is shown to provide the bulk of the dark matter.
EXTENDED KAC–MOODY ALGEBRAS AND APPLICATIONS
Authors: RAGOUCY E. , SORBA P.
Published: November 2004

We extend the notion of a Kac–Moody algebra defined on the S1 circle to super Kac–Moody algebras defined on M × GN, M being a smooth closed compact manifold of dimension greater than one, and GN the Grassman algebra with N generators. We compute all the central extensions of these algebras. Then, we determine for each such algebra the derivation algebra constructed from the M × GN diffeomorphisms. The twists of such super Kac–Moody algebras as well as the generalization to noncompact surfaces are partially studied. Finally, we apply our general construction to the study of conformal and superconformal algebras, as well as area-preserving diffeomorphisms algebra and its supersymmetric extension.
TWO-LOOP APPROACH TO THE EFFECTIVE ACTION IN QUANTUM GRAVITY
Authors: BUCHBINDER I. L. , ODINTSOV S. D. , FONAREV O. A.
Published: November 2004

For the first time we present the general formalism and results of calculation of the two-loop effective action in Einstein quantum gravity on the background MN × Tk, where MN is Minkowski space and Tk is a k-dimensional torus. We discuss the case of a zero cosmological constant as well as of a nonzero one. The method of calculating variations of the action on a metric tensor and the technique of calculating momentum integrals in dimensional regularization are presented. Some applications to spontaneous compactification are discussed, as well as some prospects.
N = 2 SUPERCONFORMAL ANOMALIES AND CURVED HARMONIC SUPERSPACE
Authors: KACHKACHI M. , LHALLABI T.
Published: November 2004

We present the differential geometry formalism of the N = 2 conformal supergravity in harmonic superspace, which allows one to derive the BRST symmetry corresponding to N = 2 super-diffeomorphisms, local Lorentz transformations and local super-Weyl transformations. The extended transgression formula is used and the N = 2 superconformal anomalies are shown.
ELECTRIC CHARGE NONCONSERVATION AND MINICHARGED PARTICLES—PHENOMENOLOGICAL IMPLICATIONS
Authors: MOHAPATRA R.N. , NUSSINOV S.
Published: November 2004

We discuss constraints on electric charge nonconservation and minicharged particles implied by terrestrial, astrophysical and cosmological considerations. We also suggest possible methods for detection of these particles in underground detectors.
THE AXIAL ANOMALY IN QCD: A SEMICLASSICAL VIEW
Authors: GHOSH KAUSHIK , PATEL BIMAL
Published: November 2004

A semiclassical understanding of the anomalies of the axial singlet and nonsinglet currents in massless QCD (coupled to an external adiabatically turned on electromagnetic field) is developed. In particular, it is clarified how these anomalies manifest themselves in the context of spontaneous symmetry breaking. For the nonsinglet current the anomaly manifests itself as a final coherent state of massless pions; for the singlet current it is argued that there is a cancellation between the gluonic and electromagnetic contributions to the anomaly, which is verified explicitly using the 1/N expansion.
ZERO CURVATURE CONDITION OF OSp(2/2) AND THE ASSOCIATED SUPERGRAVITY THEORY
Authors: DAS ASHOK , HUANG WEN-JUI , ROY SHIBAJI
Published: November 2004

The N=2 fermionic extensions of the KdV equations are derived from the zero curvature condition associated with the graded Lie algebra of OSp(2/2). These equations lead to two bi-Hamiltonian systems, one of which is supersymmetric. We also derive the one-parameter family of N=2 supersymmetric KdV equations without a bi-Hamiltonian structure in this approach. Following our earlier proposal, we interpret the zero curvature condition as a gauge anomaly equation which brings out the underlying current algebra for the corresponding 2D supergravity theory. This current algebra is then used to obtain the operator product expansions of various fields of this theory.
TETRACRITICAL ISING MODEL COUPLED TO THE TWO-DIMENSIONAL GRAVITY
Authors: KUMAR ALOK , MAHARANA JNANADEVA
Published: November 2004

Nonperturbative string equations are found explicitly for a central charge c=4/5 model coupled to the two-dimensional quantum gravity in the Lax operator approach proposed by Douglas. These string equations are used to derive the scaling behavior of several correlation functions on the sphere and it is shown that they agree with the calculations of the continuum theory. The model, identified with the diagonal modular invariant in the ADE classification, corresponds to the tetracritical Ising model.
INTEGRABLE DEFORMATIONS OF THE NONUNITARY MINIMAL CONFORMAL MODEL ℳ3,5
Authors: MUSSARDO G.
Published: November 2004

The scaling region of the nonunitary minimal conformal model M3,5 is described by three different integrable massive field theories. We propose the scattering theory for the integrable deformation of M3,5 by the field ψ with anomalous dimensions [Formula: see text]. The spectrum of this theory is confirmed by the Truncation Conformal Space Approach. We also consider the thermodynamics of the one-dimensional quantum system defined by the transfer matrix relative to the deformation of M3,5 by the field φ with anomalous dimensions [Formula: see text]. This deformation drives the original conformal model into a region of the phase diagram where there are plasma oscillations.
ON THE PARTITION FUNCTION OF STRING THEORIES DEFINED ON ALGEBRAIC CURVES
Authors: FERRARI FRANCO
Published: November 2004

In this paper the amplitudes of bosonic string theory on Riemann surfaces are studied taking the branch points as moduli. The case of a general Riemann surface of genus three is completely worked out, constructing the chiral determinants and the propagators. The chiral determinants and the partition function are given explicitly in terms of the moduli and of the parameters of the curve apart from a factor which is essentially a theta constant. The Beilinson-Manin formulae for Riemann surfaces whose moduli space is parametrized by branch points are discussed.
ALGEBRAIC DEFINITION OF TOPOLOGICAL W GRAVITY
Authors: HOSONO SHINOBU
Published: November 2004

We propose a definition of the topological W gravity using some properties of the principal three-dimensional subalgebra of a simple Lie algebra due to Kostant. In our definition, structures of the two-dimensional topological gravity are naturally embedded in the extended theories. In accordance with the definition, we will present some explicit calculations for the W3 gravity.
SUPERLOOP EQUATIONS AND TWO-DIMENSIONAL SUPERGRAVITY
Authors: ALVAREZ-GAUMÉ L. , ITOYAMA H. , MAÑES J.L. , ZADRA A.
Published: November 2004

We propose a discrete model whose continuum limit reproduces the string susceptibility and the scaling dimensions of (2, 4m) minimal superconformal models coupled to 2D supergravity. The basic assumption in our presentation is a set of super-Virasoro constraints imposed on the partition function. We recover the Neveu-Schwarz and Ramond sectors of the theory, and we are also able to evaluate all planar loop correlation functions in the continuum limit. We find evidence to identify the integrable hierarchy of nonlinear equations describing the double scaling limit as a supersymmetric generalization of KP studied by Rabin.
QUANTIZATION OF THE 2d EFFECTIVE GRAVITY IN THE GEOMETRICAL FORMULATION
Authors: AOYAMA SHOGO
Published: November 2004

There exist various formulations to discuss the 2d effective gravity: (i) light-cone gauge formulation; (ii) geometrical formulation; (iii) formulation by the constrained WZWN model; and (iv) conformal gauge formulation. In the formulations other than the last one, quantization of the 2d effective gravity is not complete in the sense that either the central charges of both sectors are not known, or one of them is known but not the other. We will provide a thorough argument on quantization of the 2d effective gravity in the formulation (ii). The argument will allow us to complete the quantization in the formulation (iii), and establish the relations among the formulations (ii)-(iv) at the quantum level.
ANOTHER LOOK AT THE CP VIOLATION PROBLEM
Authors: URBANOWSKI K.
Published: November 2004

We show that the interpretation of neutral kaon decay (and [Formula: see text] and other decay) experiments is based on a not-too-correct theoretical description of such decays. This description does not take into account the specific early time properties of temporal evolution in the two-component subspace of a state space. The particle interpretation of vectors in such a subspace is shown to be proper for other states in an early time period and other states in a long time period.
CONSTRUCTION OF GENERAL COLORED R MATRICES FOR THE YANG-BAXTER EQUATION AND q-BOSON REALIZATION OF QUANTUM ALGEBRA slq(2) WHEN q IS A ROOT OF UNITY
Authors: GE MO-LIN , SUN CHANG-PU , XUE KANG
Published: November 2004

Through a general q-boson realization of quantum algebra sl q(2) and its universal R matrix an operator R matrix with many parameters is obtained in terms of q-boson operators. Building finite-dimensional representations of q-boson algebra, we construct various colored R matrices associated with nongeneric representations of sl q(2) with dimension-independent parameters. The “nonstandard” R matrices obtained by Lee-Couture and Murakami are their special examples. We also study the factorizable structure of some Rmatrices for the indecomposable representations used in its construction.
RECOVERY OF GAUGE INVARIANCE IN STRONG-COUPLING QED
Authors: KEI-ICHI KONDO
Published: November 2004

Under a novel ansatz for the vertex function, the Schwinger- Dyson equation for the fermion propagator in the cutoff QED is solved in the arbitrary gauge, taking account of the vacuum polarization in the photon propagator. For any ultraviolet cutoff Λ, there exists a bifurcation point ec(Λ) of the bare coupling constant above which the trivial fermion-mass function for massless QED bifurcates to another, nontrivial massive solution. With a proper choice of the transverse vertex function and the longitudinal vertex that respects the Ward-Takahashi identity, the critical point ec(∞) and the critical scaling behavior in the vicinity of the critical point are shown to be gauge-independent. In the arbitrary gauge, it is shown that the quenched, planar QED obeys Miransky’s scaling of the essential-singularity type and that the unquenched QED exhibits the mean-field critical behavior with classical critical exponents.
Quantum Groups: Singular Vectors and BGG Resolution
Authors: Malikov Fyodor
Published: November 2004

We prove existence of BGG resolution of an irreducible highest weight module over a quantum group, classify morphisms of Verma modules over a quantum group and find formulas for singular vectors in Verma modules. As an application we find cohomology of the quantum group of the type [Formula: see text] with coefficients in a finite-dimensional module.
ON SCHUR-WEYL DUALITY, An HECKE ALGEBRAS AND QUANTUM sl(N) ON $\otimes^{n+1}{\mathbb C}^N$
Authors: MARTIN PAUL PURDON
Published: November 2004

We prove that an N-state vertex model representation of the An Hecke algebra quotient NHn(q) is faithful for all q. We use the result to examine the indecomposable content of these representations, and hence the structure of the centraliser algebra, which is generically a quotient of Uqsl(N), at q a root of unity. We achieve a complete analysis in the case N=2, finding a number of Morita self-dual algebraic structures.
ROW TRANSFER MATRIX FUNCTIONAL EQUATIONS FOR A–D–E LATTICE MODELS
Authors: PEARCE PAUL A.
Published: November 2004

Determinantal functional equations satisfied by the row transfer matrix eigenvalues of critical A–D–E lattice spin models are presented. These are obtained for models associated with the Lie algebras [Formula: see text], [Formula: see text], AL, DL and E6,7,8 by exploiting connections with functional equations satisfied by the row transfer matrix eigenvalues of the six-vertex model at rational values of the crossing parameter λ=sπ/h where h is the Coxeter number. In addition, fusion is used to derive special functional equations, called inversion identity hierarchies, which provide the key to the direct calculation of finite-size corrections, central charges and conformal weights for the critical A–D–E lattice models.
CYCLIC MONODROMY MATRICES FOR THE R-MATRIX OF THE SIX-VERTEX MODEL AND THE CHIRAL POTTS MODEL WITH FIXED SPIN BOUNDARY CONDITIONS
Authors: TARASOV VITALY O.
Published: November 2004

Irreducible cyclic representations of the algebra of monodromy matrices corresponding to the R-matrix of the six-vertex model are described. As a consequence, the direct computation of spectra for transfer-matrices of the chiral Potts model with special fixed-spin boundary conditions is done. The generalization of simple Baxter's Hamiltonian is proposed.
MULTICOMPONENT CHIRAL POTTS MODELS
Authors: AU-YANG HELEN , PERK JACQUES H. H.
Published: November 2004

It is shown that an (Nρ,Nσ) chiral Potts model, which is a generalization of the Ashkin-Teller model and consists of two chiral Potts models which are coupled together by four-spin interactions, can always be mapped to a single chiral Potts model of NρNσ states if Nρ and Nσ are relative prime. Moreover, if on every lattice site there are d spins with Nρ,…,Nσ states, respectively, similar mappings exist: If there are chiral two-spin interactions between nearest neighbor spins of the same kind and if the d sublattices are coupled together by chiral 2j-spin interactions for j≤d between the j pairs of spins, this defines a composite (Nρ,…,Nσ) state chiral Potts model. If (Ni,Nj)=1, for i≠j, i,j=1,…,d, then the composite model with (Nρ,…,Nσ) states can be mapped into a [Formula: see text]-state chiral Potts model. Finally, it is shown that if one or more of the spins of a unit cell sits on the dual lattice whereas the other spins sit on the original lattice, so that this is a generalization of the eight-vertex model in the spin language, such a mapping also exists. This mean that results obtained for the chiral Potts models can be used for many such composite models.
METHODOLOGIES FOR EVALUATING THINNING ALGORITHMS FOR CHARACTER RECOGNITION
Authors: PLAMONDON RÉJEAN , SUEN CHING Y. , BOURDEAU MARC , BARRIÈRE CAROLINE
Published: November 2004

This paper investigates three different methods of comparing preference structures for thinning algorithms. The first method involves a series of experiments with human subjects. The second makes use of neural networks and the third is based on dissimilarities and distance measures that is computer generated. Several statistical tests have been performed to analyze the preference structures exhibited by the data. This study highlights human coherence in comparing skeletons and the novelty of using reference skeletons to facilitate the evaluation of thinning algorithms. None of the automatic approaches provides a useful insight although a measure of information content manifests some consistency. The overall study suggests a systematic protocol involving human coherence to evaluate preprocessing algorithms.
IMAGE PROCESSING AND COMPUTER AIDED DIAGNOSIS IN DIGITAL MAMMOGRAPHY: A CLINICAL PERSPECTIVE
Authors: PISANO ETTA D. , SHTERN FAINA
Published: November 2004

Mammographic technology has improved dramatically in the last two decades. The advent of digitally acquired mammograms offers the possibility of further improvements in early breast cancer detection. Specifically, digital acquisition systems decouple the process of X-ray photon detection from image display by using a primary detector that directly quantifies transmitted photons. Digital systems also allow a wide dynamic range so that a wider range of tissue contrast can be appreciated. Digital systems have the capacity to bring revolutionary advantages to breast cancer detection and management (1) image processing for increased lesion conspicuity; (2) computer-aided diagnosis for enhanced radiologic interpretation; (3) teleradiology, or image transmission, as a means of bringing world-class expertise to community hospitals and remote areas; (4) improved image access and communication through digital image archiving and transmission; and (5) dynamic, or “real time” imaging for use during biopsy and localization procedures. In this article, the authors review the literature 011 the use of image processing and computer assisted diagnosis for digital mammography. Future research goals in the development of digital mammography are also discussed.
SOUND AND MUSIC FROM CHUA'S CIRCUIT
Authors: RODET XAVIER
Published: November 2004

Nonlinear Dynamics have been very inspiring for musicians, but have rarely been considered specifically for sound synthesis. We discuss here the signals produced by Chua's circuit from an acoustical and musical point of view. We have designed a real-time simulation of Chua's circuit on a digital workstation allowing for easy experimentation with the properties and behaviors of the circuit and of the sounds. A surprisingly rich and novel family of musical sounds has been obtained. The audification of the local properties of the parameter space allows for easy determination of very complex structures which could not be computed analytically and would not be simple to determine by other methods. Finally, we have found that the time-delayed Chua's circuit can model the basic behavior of an interesting class of musical instruments.
CONTROLLING OF CHAOS IN THE DRIVEN CHUA'S CIRCUIT
Authors: MURALI K. , LAKSHMANAN M.
Published: November 2004

The nonautonomous version of Chua's circuit can exhibit a wide variety of bifurcation routes to chaos. In this paper we explore the possibility of controlling chaos in this circuit by the addition of a second periodic signal for certain parametric choices.
CHUA'S CIRCUIT AS A SLOW-FAST AUTONOMOUS DYNAMICAL SYSTEM
Authors: ROSSETTO BRUNO
Published: November 2004

We apply the singular perturbation method to Chua's equations, considered as a slow-fast autonomous dynamical system (S-FADS). An algorithm available for most nonlinear S-FADS generalizes the singular perturbation method, gives the nth-order approximation equations, and allows us to go further with a qualitative study. This algorithm is applied to the Chua's system in a very simple way. Indeed, because this system is integrable, it is possible to compute explicitly the slow and fast dynamics for a better understanding of the nonlinear cases.
EDGE COVERING OF COMPLEX TRIANGLES IN RECTANGULAR DUAL FLOORPLANNING
Authors: SUN YACHYANG , YEAP KOK-HOO
Published: November 2004

Rectangular dual graph approach to floorplanning is based on the adjacency graph of the modules in a floorplan. If the input adjacency graph contains a cycle of length three which is not a face (complex triangle), a rectangular floorplan does not exist. Thus, complex triangles have to be eliminated before applying any floorplanning algorithm. This paper shows that the weighted complex triangle elimination problem is NP-complete, even when the input graphs are restricted to 1-level containment. For adjacency graph with 0-level containment, the unweighted problem is optimally solvable in O(c1.5 + n) time where c is the number of complex triangles and n is the number of vertices of the input graph.
HOMOCLINIC BIFURCATION IN HIGHER DEGREE SYSTEMS WITH APPLICATION TO RANDOM FLIPPING MODES
Authors: SMITH PETER , YORKE JENNIFER M.E.
Published: November 2004

Bifurcations from stable homoclinic saddle connections for a class of second-order differential equations of forced van der Pol-Duffing type are investigated using a new method based on a two-parameter perturbation series. The underlying autonomous system is parametrically tuned for homoclinic orbits and then perturbed by small amplitude forcing. These systems exhibit an apparent random flipping about the saddle point. Asymptotic conditions for switching between half-cycles are obtained and compared with numerically integrated solutions for a model system.
NONANALYTIC DYNAMICS FOR GENERATING THE MANDELBROT SET: A TUTORIAL
Authors: METZLER W. , BRELLE A. , SCHMIDT K.-D.
Published: November 2004

From experimental work, nonanalytic quadratic maps are known which generate the Mandelbrot set as well as Julia sets not different from those obtained by the complex analytic quadratic family z↦z2+c, c∈C. This paper presents a tutorial on how to generate analytically the complete class of real parameter-dependent quadratic maps of the plane, all having, for instance, the Mandelbrot set in common with the quadratic family. In the analytical case, the transformations involved are rotations or reflections.
DYNAMICS OF TWO LOGISTIC MAPS WITH A MULTIPLICATIVE COUPLING
Authors: LÓPEZ-RUIZ R. , PÉREZ-GARCÍA C.
Published: November 2004

The dynamical behavior of a system formed by two symmetrically coupled logistic maps with a multiplicative coupling is analyzed. The transition to chaos (Ruelle-Takens type) and the multifractal properties of the attractor have been determined in this system. This transition cannot be deduced from the subharmonic cascade typical of a single logistic map. Under the same kind of symmetry, different classes of coupling in 2D maps give the same qualitative route to chaos but with different geometrical transition mechanisms.
MEMORY EFFECTS IN DISCRETE DYNAMICAL SYSTEMS
Authors: AICARDI FRANCESCA , INVERNIZZI SERGIO
Published: November 2004

Let fµ(s)=µs(1−s) be the family of logistic maps with parameter µ, 1≤µ≤4. We present a study of the second-order difference equation xn+1=fµ([1−∈]xn+∈xn−1), 0≤∈≤1, which reduces to the well-known logistic equation as ∈=0.
EXPERIMENTAL DEMONSTRATION OF SECURE COMMUNICATIONS VIA CHAOTIC SYNCHRONIZATION
Authors: KOCAREV Lj. , HALLE K. S. , ECKERT K. , CHUA L. O. , PARLITZ U.
Published: November 2004

Secure communications via chaotic synchronization is experimentally demonstrated using Chua's circuit. In our experiment the energy lost in the information-bearing signal is approximately 0.6 dBV. The reduction in chaotic signal after the recovery process is between -40 and -50 dBV.
ADA REUSABILITY AND SYSTEM DESIGN ASSESSMENT USING THE DATA BINDING TOOL
Authors: DELIS ALEX , BASILI VICTOR R.
Published: November 2004

This paper reports on the development of the data binding tool and its use in Ada source code reusability and software system design assessment. The tool was built around the metric of data bindings. Data bindings fall in the category of data visibility metrics and are used to measure inter-component interactions. Software system components are defined in the context of the Ada language using a flexible scheme. They are used, along with cluster analysis, to present structural configurations of a software system. The clustering technique as well as the tool design and its problems are discussed. The analysis of dendrograms (trees of components produced by the tool) reveals several classes of systems dendrograms and provides a simple mechanism for Ada source code reusability. Finally, the implications of different design methodologies used to develop the test software are discussed and explanations for the several types of dendrogram formulations are given.
P-COMPLETE GEOMETRIC PROBLEMS
Authors: ATALLAH MIKHAIL J. , CALLAHAN PAUL B. , GOODRICH MICHAEL T.
Published: November 2004

In this paper we show that it is impossible to solve a number of “natural” two-dimensional geometric problems in polylog time with a polynomial number of processors (unless P=NC). Thus, we disprove a popular belief that there are no natural P-complete geometric problems in the plane. The problems we address include instances of polygon triangulation, planar partitioning, and geometric layering. Our results are based on non-trivial reductions from the monotone circuit value and planar circuit value problems.
COMPUTATION OF STIMULATED BRILLOUIN SCATTERING (SBS) WITH FOCUSSED PUMP BEAMS
Authors: MENZEL R. , EICHLER H.J.
Published: November 2004

The spatial and temporal sound wave distribution in stimulated Brillouin scattering (SBS) cells was calculated for focussed laser beams. The pump power was varied up to the saturation values. The spontaneous scattering was determined from comparison with experimental results. Using this model the influence of the pulse length, the focal length, the cell length and other parameters on the distribution of the sound wave and the SBS-reflectivity can be discussed.
PRAGMATIC TESTING METHODS FOR EXPERT SYSTEMS
Authors: TSAI W.T. , ZUALKERNAN I.A. , KIRANI SHEKHAR
Published: November 2004

Effective testing of expert systems is an important but difficult task. In this paper we discuss why testing of expert systems is hard. For testing expert systems, testing techniques from conventional software engineering are adapted as a solution to these problems. We discuss the feasibility and application of black-box, white-box, and life-cycle testing techniques to expert systems. Black-box techniques include random, input partition and output partition testing. White-box techniques include path based partition, cause-effect graph, dynamic-flow, data-flow, and ablation testing. The use of these methods is demonstrated by applying the techniques to an industrial expert system.

The results obtained are 1) random testing is feasible for expert systems with a small input space, 2) effectiveness of partition testing depends on the partition criteria, however, partition testing points out failure-prone partitions, 3) cause-effect testing is suitable for large expert systems if it is well decomposed, 4) dynamic-flow testing depends on the number of paths in solution and design specifications, 5) data-flow testing is feasible only if define-use pairs are obtained automatically, 6) ablation testing helps in pointing out discrepancies between specification and implementation. The overall result is that the expert systems can be treated as any other software and all the conventional software engineering testing techniques can be used to test expert systems.
ON AUTOMATIC REASONING FOR SCHEMA INTEGRATION
Authors: SHETH AMIT P. , GALA SUNIT K. , NAVATHE SHAMKANT B.
Published: November 2004

Success in database schema integration depends on the ability to capture real world semantics of the schema objects, and to reason about the semantics. Earlier schema integration approaches mainly rely on heuristics and human reasoning. In this paper, we discuss an approach to automate a significant part of the schema integration process.

Our approach consists of three phases. An attribute hierarchy is generated in the first phase. This involves identifying relationships (equality, disjointness and inclusion) among attributes. We discuss a strategy based on user-specified semantic clustering. In the second phase, a classification algorithm based on the semantics of class subsumption is applied to the class definitions and the attribute hierarchy to automatically generate a class taxonomy. This class taxonomy represents a partially integrated schema. In the third phase, the user may employ a set of well-defined comparison operators in conjunction with a set of restructuring operators, to further modify the schema. These operators as well as the automatic reasoning during the second phase are based on subsumption.

The formal semantics and automatic reasoning utilized in the second phase is based on a terminological logic as adapted in the CANDIDE data model. Classes are completely defined in terms of attributes and constraints. Our observation is that the inability to completely define attributes and thus completely capture their real world semantics imposes a fundamental limitation on the possibility of automatically reasoning about attribute definitions. This necessitates human reasoning during the first phase of the integration approach.
THE (2, ∞)-SKEIN MODULE OF LENS SPACES: A GENERALIZATION OF THE JONES POLYNOMIAL
Authors: HOSTE JIM , PRZYTYCKI JÓZEF H.
Published: November 2004

We extend the Jones polynomial for links in S3 to links in L(p, q), p>0. Specifically, we show that the (2, ∞)-skein module of L(p, q) is free with [p/2]+1 generators. In the case of S1×S2 the skein module is infinitely generated.
STRINGS FROM BLACK HOLES
Authors: ODA ICHIRO
Published: November 2004

It is shown that surface fluctuation of the event horizon of black holes in four dimensions which have been previously studied by ’t Hooft can be understood in terms of the topological two-dimensional string. This interpretation is valid at the lowest order, with respect to the magnitude of the radial momentum per magnitude of the transverse momentum, when particles near the event horizon fall into the black hole and from which particles then emit to future null infinity, owing to the Hawking radiation. This implies that in such a kinematical regime only the zero mode, that is, the center-of-mass momentum of the Euclidean string, propagates on the surface of the event horizon.
WHEN GRAVITATIONAL WAVES COLLIDE!
Authors: CHAKRABARTI SANDIP K.
Published: November 2004

We briefly discuss the nature of spacetimes after two impulsive gravitational waves collide. The discussion is based mainly on recent works of Chandrasekhar and Xanthopoulos.
PERTURBATIONS OF A STRINGY BLACK HOLE
Authors: RAITEN E.
Published: November 2004

We extend the three-dimensional stringy black hole of Horne and Horowitz to four dimensions. After a brief discussion of the global properties of the metric, we discuss the stability of the background with respect to small perturbations, following the methods of Gilbert and of Chandrasekhar. The potential for axial perturbations is found to be positive definite.
THE INFLUENCE OF THE INERTIAL DRAGGING EFFECT ON GRAVITATIONAL RADIATION EMITTED FROM A PARTICLE MOVING IN EQUATORIAL GEODESIC CIRCULAR ORBIT ABOUT A KERR’S BLACK HOLE
Authors: GONG BIPING
Published: November 2004

Using Chranowski and Misner’s equations,1 gravitational radiation emitted from a particle moving in an equatorial geodesic circular orbit about a Kerr’s black hole is calculated. Outside the classical turning point, the radiation energy can be represented as a continuous function of orbital radius of the particle, and thus a corresponding curve is obtained.

Using Wilkins’ approach,2 two inertial dragging related functions are obtained by restricting the orbit of the particle to the equatorial plane of a Kerr’s black hole.

By comparing the curve of the gravitational radiation and the curves of the simulating functions (consisting of the angular frequency and the drag related function), we come to the conclusion that inertial dragging effect on a particle is one of the main factors that influences the gravitational radiation.
NEUTRON STARS AND SCALAR FIELDS
Authors: BENSON G.J. , MOORHOUSE R.G. , HENRIQUES A.B.
Published: November 2004

We calculate and discuss the possible consequences of the existence of light scalar particles on the properties of neutron stars. We take the mass and coupling to matter of this hypothetical scalar to be free parameters in our model and present results for a wide range of these. In highlighting the contrasting cases of scalar presence and absence, we have used two equations of state for the matter — the first being the relatively simple equation of state for an ideal gas of fermions; the second, which is more sophisticated, being based upon considerations of nucleon-nucleon interactions. Our results show that, for certain values of scalar mass and coupling, significant changes in the structure of the star can arise. We then examine how the presence of this scalar field can affect the cooling of mature neutron stars via alterations to the modified URCA process. Finally, we combine the results of our calculations with observational data on neutron stars, and compare our resulting bounds on the scalar particle coupling to those obtainable by other means.
ON IDENTIFYING THE PRESENT-DAY VACUUM ENERGY WITH THE POTENTIAL DRIVING INFLATION
Authors: FREWIN RICHARD A. , LIDSEY JAMES E.
Published: November 2004

There exists a growing body of observational evidence supporting a nonvanishing cosmological constant at the present epoch. We examine the possibility that such a term may arise directly from the potential energy which drove an inflationary expansion of the very early universe. To avoid arbitrary alterations in the shape of this potential at various epochs it is necessary to introduce a time-dependent viscosity into the system. The evolution of the effective Planck mass in scalar-tensor theories is a natural candidate for such an effect. In these models there are observational constraints arising from anisotropies in the cosmic microwave background, large-scale galactic structure, observations of the primordial Helium abundance and solar system tests of general relativity. Decaying power law and exponential potentials are considered, but for these models it is very difficult to simultaneously satisfy all of the limits. This may have implications for the joint evolution of the gravitational and cosmological constants.
ARE BLACK HOLES IN BRANS-DICKE THEORY PRECISELY THE SAME AS IN GENERAL RELATIVITY?
Authors: CAMPANELLI M. , LOUSTO C.O.
Published: November 2004

We study a three-parameter family of solutions of the Brans-Dicke field equations. They are static and spherically symmetric. We find the range of parameters for which this solution represents a black hole different from the Schwarzschild one. We find a subfamily of solutions which agrees with experiments and observations in the solar system. We discuss some astrophysical applications and the consequences on the “no hair” theorems for black holes.
NÖTHER’S SYMMETRIES IN (n+1)-DIMENSIONAL NONMINIMALLY COUPLED COSMOLOGIES
Authors: CAPOZZIELLO SALVATORE , DE RITIS RUGGIERO , SCUDELLARO PAOLO
Published: November 2004

We perform a systematic analysis of nonminimally coupled cosmologies in (n+1)-dimensional homogeneous and isotropic spacetimes, searching for Nöther’s symmetries and generalizing the results of our previous works. We obtain (i) the absence of symmetries when the spatial curvature constant k is nonzero and n=2, 3, but their existence for all the other n; (ii) the existence of such symmetries for every number of spatial dimensions (except n=1) when k=0. In this latter case, we are able to find a general transformation through which we recover the string-dilaton effective action in (n+1) dimensions and the major peculiarity of string cosmology: the scale factor duality. Furthermore, the symmetry fixes a relation among the coupling F(ϕ), the potential V(ϕ) of the scalar field ϕ, the number of spatial dimensions and the spatial curvature constant. When this is the case, it is possible to find a constant of motion and then get the general solution of the dynamics. Finally, in the framework of the so-called Induced Gravity Theories, we are able to obtain the Newton constant at the present time (t→∞) depending on the number of spatial dimensions and directly related to the constant of motion existing in such a model.
NUCLEAR MATTER STABILITY IN A SOLITON MODEL FOR FINITE NUCLEI
Authors: DERRETH CH. , ELZE H.-TH. , GREINER W.
Published: November 2004

A relativistic band structure method for the computation of the electronic structure of atomic clusters is adapter to the Friedberg–Lee nontopological soliton model. Thus, finite nuclei can be studied in the soliton model. As a verification of our method, we calculated the equation of state of nuclear matter. In order to achieve nuclear matter stability, we added the colour magnetic interaction for an inhomogeneous dielectric medium as well as a phenomenological residual interaction to the soliton model. Both modifications are examined in detail. Nuclear matter stability near the empirical ground state density and binding energy has been achieved.
J/Ψ SUPPRESSION IN EXPANDING HADRONIC MATTER WITH A PHASE TRANSITION
Authors: PROROK DARIUSZ
Published: November 2004

J/Ψ propagation in hadronic matter expanding longitudinally and transversely in the central rapidity region of a nucleus-nucleus collision is examined. During the expansion, a first order transition from the quark-gluon plasma to the hadronic state occurs. The J/Ψ suppression in matter is due to the combined effects of the plasma, the mixed phase and hadrons on the resonance. Finally, J/Ψ momentum distributions for the model which assumes a J/Ψ formation time and for the one where J/Ψ dissolution is described on the quantum level are presented.
MICROSCOPIC TREATMENT OF THE LOW LYING STATES IN THE TRANSITIONAL REFLECTION ASYMMETRIC 219,221Fr NUCLEI
Authors: KVASIL J. , SHELINE R. K. , HŘIVNÁČOVÁ I. , LIANG C. F. , PARIS P.
Published: November 2004

A microscopic treatment of the low lying states in 219 Fr and 221 Fr using intermediate coupling of the appropriate reflection symmetric quasiparticles and octupole degrees of freedom is compared with the strong coupling treatment. Both theories give the experimentally observed parity doublets and, for K = 1/2± bands, decoupling parameters with opposite signs but similar absolute magnitudes.
A MODEL OF ALLELOCHEMICAL INTERACTIONS BETWEEN SOFT AND SCLERACTINIAN CORALS ON THE GREAT BARRIER REEF
Authors: ANTONELLI P.L. , SAMMARCO P.W. , COLL J.C.
Published: November 2004

The mathematical theory of Volterra-Hamilton systems developed for modelling allelopathic interactions in sessile communities, is utilized here to model cost of terpene production of colonizing soft corals and their highly toxic effects on scleractinian corals of the Great Barrier Reef. The central question asked is what strategies of hard corals, if any, would enable them to survive colonization. Several detailed results are obtained relating quantitative measures of terpene production (v), soft coral encroachment (µ), allelopathic vigour (–K) and community production stability. The model predicts that any factor which reduces soft coral encroachment (which includes direct toxic effects) has survival value. Thus, spatial shapes and distributions of scleractinians or refuge in space, in themselves, may constitute viable “cost-effective” competitive defenses. It is unlikely, however, that scleractinian corals could evolve in such a way as to specifically neutralize terpenes directly, according to this model, although their species-specifically variable resistance to their effects can be accounted for.
A STATISTICAL ANALYSIS OF MULTIPLE SCALES IN INSECT POPULATIONS.: A CASE STUDY: THE CHESTNUT WEEVIL CURCULIO ELEPHAS
Authors: DEBOUZIE D. , HEIZMANN A. , HUMBLOT L.
Published: November 2004

Populations of the chestnut weevil (Coleoptera: Curculionidae) living in 14 patches (13 with chestnut trees, 1 with oak) were studied over a period of twelve years.

Four spatial scales were considered: the patch (one or several trees), the chestnut tree (for patches with several trees), the chestnut-husk and the chestnut. Heterogeneity was the highest between trees and among chestnuts; it was larger in multiple-tree patches than in single-tree patches. The infestation rate per tree varied from 0 to 0.41 immature weevils per fruit. The distribution of immature weevils per chestnut was highly contagious.

Different mechanisms are implied at the two main scales, trees and chestnuts, and must be incorporated in a hierarchical model of population dynamics. Difficulties due to the application of metapopulation concept to natural populations of insects are underlined.
ON THE INTEGRATION OF UNCERTAINTY THEORIES
Authors: RESCONI GERMANO , KLIR GEORGE J. , CLAIR UTE ST. , HARMANEC DAVID
Published: November 2004

Investigations pursued in this paper contribute to a research project introduced by Resconi, Klir, and St. Clair [1] whose purpose is to employ syntactic and semantic structures of modal logic as a unifying framework within which various uncertainty theories can be formalized, compared, and organized hierarchically. This paper focuses on the explicit use of modal logic semantics to formalize fuzzy sets, belief measures, plausibility measures, and Sugeno λ-measures.
PROJECTION PURSUIT BASED ON MAXIMUM DEPENDENCE
Authors: GUIASU SILVIU
Published: November 2004

The objective of this paper is to give criteria for selecting the best pair or triple of characteristics from a larger set of characteristics used for describing a given system of entities, that can still reveal the clustering of the system of entities in subsystems. The proposed criteria are based on the entropic measures of inner and outer interdependence. The formalism is applied to Anderson's Iris Classification Problem.
ON THE COMPLETION OF PRIORITY ORDERINGS IN NONMONOTONIC REASONING SYSTEMS
Authors: YAGER RONALD R.
Published: November 2004

We discuss the structure of nonmonotonic reasoning. We suggest that an important aspect of nonmonotonic reasoning systems is the ordering relationship (preference structure) on the propositions in the knowledge. We suggest that this ordering relationship must be a weak order, a complete and transitive relationship. We provide a comprehensive discussion of some central issues in preference theory. In most real applications of nonmonotonic knowledge bases the ordering relationship available is often not complete. We suggest a mechanism for completing these relationships. The basic imperative used in providing this completion is to do it in such a manner as to add as few unjustified inferences as necessary. To formally accomplish this task we introduce a measure of buoyancy associated with a weak order and suggest that the preferred completion is the one with the maximal buoyancy.
AN INTERNATIONAL SURVEY OF ENTREPRENEURSHIP EDUCATION
Authors: Dana Leo-Paul
Published: November 2004

Entrepreneurship skills are very different from managerial skills. Physiologically, entrepreneurial skills are the function of a developed right hemisphere of the brain, while managerial skills are processed in the left side of the brain. The development of entrepreneurs, therefore, is quite different from managerial development.

According to Distinguished Professor Raymond W.Y. Kao, many people lose their entrepreneurial spirit because of the educational system. The problem appears to stem from the fact that traditional education teaches to formalize before doing, while entrepreneurs prefer action rather than pen and paper.

This paper begins with a literature review. It then describes and analyzes entrepreneurship education in Canada, the US, Australia and Europe. It explains what is being taught and how.

Based on the curriculum of almost fifty schools of business, the author develops a learning agenda, ranging from business basics and techniques, to character development skills and integration. Recommendations are then made, based on outstanding examples of entrepreneurship education in different countries.