bluuebunny/crossref_metadata_2025 huggingface dataset:
COMPUTED TOMOGRAPHIC EVALUATION OF CANINE AND FELINE MEDIASTINAL MASSES IN 14 PATIENTS
Authors: Yoon Junghee , Feeney Daniel A. , Cronk Daniel E. , Anderson Kari L. , Ziegler Laura E.
Published: November 2004

A 15‐year retrospective analysis of histologically proven canine and feline mediastinal malignancies at the University of Minnesota was conducted to identify patients imaged by computed tomography (CT). The goal of the study was to characterize the CT appearance, to determine if there were any tumor type‐specific appearances, and to clarify the role of CT in patients with mediastinal masses. Fourteen patients meeting these criteria were available for evaluation. The masses were characterized based on the presence or absence of contrast enhancement, internal architecture, size, extent of local invasion, the presence of pleural fluid, and the presence of regional vascular invasion. Within the limits of this study and the histopathologic information available, there appeared to be no clinically exploitable relationship between the CT appearance and the histologic characterization of the mass. However, CT does provide reasonably accurate local staging information.
Standards of Time and Frequency at the Outset of the 21st Century
Authors: Diddams S. A. , Bergquist J. C. , Jefferts S. R. , Oates C. W.
Published: November 2004

After 50 years of development, microwave atomic clocks based on cesium have achieved fractional uncertainties below 1 part in 10
15
, a level unequaled in all of metrology. The past 5 years have seen the accelerated development of optical atomic clocks, which may enable even greater improvements in timekeeping. Time and frequency standards with various levels of performance are ubiquitous in our society, with applications in many technological fields as well as in the continued exploration of the frontiers of basic science. We review state-of-the-art atomic time and frequency standards and discuss some of their uses in science and technology.
The effects of particulate air pollution on daily deaths: a multi-city case crossover analysis
Authors: Schwartz J
Published: November 2004

Background:Numerous studies have reported that day-to-day changes in particulate air pollution are associated with day-to-day changes in deaths. Recently, several reports have indicated that the software used to control for season and weather in some of these studies had deficiencies.

Aims:To investigate the use of the case-crossover design as an alternative.

Methods:This approach compares the exposure of each case to their exposure on a nearby day, when they did not die. Hence it controls for seasonal patterns and for all slowly varying covariates (age, smoking, etc) by matching rather than complex modelling. A key feature is that temperature can also be controlled by matching. This approach was applied to a study of 14 US cities. Weather and day of the week were controlled for in the regression.

Results:A 10 μg/m3increase in PM10was associated with a 0.36% increase in daily deaths from internal causes (95% CI 0.22% to 0.50%). Results were little changed if, instead of symmetrical sampling of control days the time stratified method was applied, when control days were matched on temperature, or when more lags of winter time temperatures were used. Similar results were found using a Poisson regression, but the case-crossover method has the advantage of simplicity in modelling, and of combining matched strata across multiple locations in a single stage analysis.

Conclusions:Despite the considerable differences in analytical design, the previously reported associations of particles with mortality persisted in this study. The association appeared quite linear. Case-crossover designs represent an attractive method to control for season and weather by matching.
PIXE ANALYSIS OF ANCIENT EARTHENWARE (MIDDLE JOMON PERIOD) EXCAVATED AT TERAMAE SITE IN FUKUSHIMA PREFECTURE
Authors: HAMANAKA H. , ITO G. , OGURA J. , YAMAMOTO Y.
Published: November 2004

Particle induced x-ray emission (PIXE) measurements were applied to analyze constituent elements in ancient earthenware (middle Jomon period) excavated at Teramae site in Fukushima prefecture. Quantitative analyses of the earthenware and clay obtained near the site show difference in contents of the constituent elements between them.
PIXE Analysis of Brain Tumor: sample preparation and its clinical feature
Authors: OTAWARA Y. , WADA T. , KIRIKAE M. , SUZUKI M. , KURODA S. , OGAWA A. , SERA K. , FUTATSUGAWA S.
Published: November 2004

As sample preparation technique for PIXE analysis of brain tumor, “homogenizing method” and “chemical ashing method” have been studied and developed. It is concluded that chemical ashing method is quite appropriate for biological sample preparation. By taking samples of surgically removed brain tumor (meningioma) and brain tumor cell line (rat glioma and human glioblastoma), elemental constitution of brain tumor is compared with that of normal brain, and remarkably high concentration of Zn is found in brain tumor.
PIXE ANALYSIS OF OTOLITHS FROM SEVERAL SPECIES OF TELEOST FISH
Authors: ARAI NOBUAKI , SAKAMOTO WATARU , MAEDA KUNIKO
Published: November 2004

In-air PIXE was used to analyze trace elements in otoliths from several species of teleost fish in order to examine the correlation between the trace elements concentrations and environmental conditions. Mn, Fe, Zn and Sr were detected accurately in the order of ppm by using the in-air PIXE. It seemed that concentrations of Sr and Zn in red sea bream otoliths increased in proportion to higher seawater temperature. In addition, there were significant differences in trace element composition between that of reared red sea bream and rockfish and that of wild ones. Preliminary results indicate that the PIXE is a powerful technique to investigate fish otoliths.
SABSA: SWITCHING-ACTIVITY-BASED STATE ASSIGNMENT
Authors: WASHABAUGH SCOTT , FRANZON PAUL D. , NAGLE H. TROY
Published: November 2004

Many algorithms have been proposed for the state assignment of Finite-State Machines. The usual goal of these algorithms is to reduce the area required to implement these machines. This paper discusses SABSA, an algorithm whose goal is to reduce the number of state bit transitions in the operating environment. SABSA does this by considering measured transition probabilities between states. When combined with a technology such as CMOS, this leads to lower power consumption. A RISC controller was taken from high level design to transistor level layout, and a power reduction of 35% was obtained with this new state assignment algorithm.
AlGaAs/GaAs HBTs FOR ANALOG AND DIGITAL APPLICATIONS
Authors: WANG KEH-CHUNG , NUBLING RANDALL B. , PEDROTTI KEN , SHENG NENG-HAUNG , ASBECK PETER M. , POULTON KEN , CORCORAN JOHN , KNUDSEN KNUD , YUAN HAN-TZONG , CHANG CHRISTOPHER
Published: November 2004

AlGaAs/GaAs Heterojunction Bipolar Transistor (HBT) technology has emerged as an important IC technology for high performance electronic systems. Many outstanding circuits have been demonstrated as a result of the AlGaAs/GaAs HBTs high speed, high accuracy and its semi-insulating substrate. Several GaAs HBT manufacturing lines have been established; some of which are shipping products. In this paper, we describe AlGaAs/GaAs HBT technology, summarize some key and representative circuits in analog, A/D conversion and digital applications, and provide prospects of GaAs HBT research.
RECENT DEVELOPMENTS IN GaInP/GaAs HETEROJUNCTION BIPOLAR TRANSISTORS
Authors: LIU WILLIAM , BEAM EDWARD , TAE KIM , KHATIBZADEH ALI
Published: November 2004

We review the recent developments of GaInP/GaAs heterojunction bipolar transistors (HBTs) used for microwave power, low noise, linear amplification and high temperature applications. Special attention is paid in the comparison of the GaInP HBT results with the more conventional AlGaAs HBTs. The material and processing advantages, as well as the electronic and thermal properties of GaInP are described.
COMPUTING EXTERNAL WATCHMAN ROUTES ON PRAM, BSR, AND INTERCONNECTION NETWORK MODELS OF PARALLEL COMPUTATION
Authors: GEWALI LAXMI P. , STOJMENOVIC IVAN
Published: November 2004

An external watchman route in the presence of a polygonal obstacle is a closed path such that each point in the exterior of the polygon is visible to some point along the route. We adapt the merging slopes technique of parallel computational geometry to develop a parallel algorithm for computing a shortest external watchman route in the presence of a convex polygon of n sides. The algorithm runs in O( log n) time using [Formula: see text] processors in the CREW-PRAM computational model; this is optimal within a constant factor. The algorithm can be easily adapted to compute a shortest watchman route in O( log n) time on a hypercube with O(n) processors. We also discuss the computation of a shortest external watchman route on star and pancake networks. Finally, a constant time algorithm for solving the merging slopes problem on a BSR with n processors is described. This leads to algorithms with the same time and processor count for solving the external watchman route problem, for computing Minkowski sum, critical support lines, and separability of two convex polygons, for finding the maximum distance between two convex polygons, and for computing the smallest enclosing box, diameter, and width of a convex polygon.
ON THE INTRACTABILITY OF TASK ALLOCATION IN DISTRIBUTED SYSTEMS
Authors: ALI HESHAM H. , EL-REWINI HESHAM
Published: November 2004

The fast progress of large integration technology has made distributed computing economically attractive for many computer applications. Task allocation is one of the most important and challenging problems in distributed computing systems that has received considerable attention in recent years. Several researchers have introduced different heuristics to solve this problem with the assumption that it is computationally intractable. These researchers have been referring to an early work by Stone and some private communication as their sources of the problem’s intractability. However, neither Stone’s paper nor any other related work in the literature provided a formal proof of intractability. Due to the importance of the task allocation problem, we believe that a formal proof of its complexity must be provided. In this paper we provide a proof that the problem of task allocation is intractable even in the restricted case when there are only two values of the the communication cost: zero or one. We introduce a new model to represent the problem of allocating tasks on heterogeneous distributed systems using split graphs. This model allows us to relate the task allocation problem with the problem of weighted clique partitioning in complete split graphs. We provide a two-step reduction method to prove the intractability of task allocation in the restricted case mentioned above. In the first step, we prove that the problem of weighted clique partitioning in complete split graph is NP-complete using a transformation from the problem of partition into triangles. In the second step, we show that the task allocation problem is NP-complete using a transformation from the weighted clique partitioning problem.
PARALLEL CREATION OF LINEAR OCTREES FROM QUADTREE SLICES
Authors: SWIFT L.K. , JOHNSON T. , LIVADAS P.E.
Published: November 2004

Quadtrees and octrees are hierarchical data structures for efficiently storing image data. Quadtrees represent two dimensional images, while octrees are a generalization to three dimensions. The linear form of each is an abstraction of the tree structure to reduce storage requirements. We have developed a parallel algorithm to efficiently create a linear octree from quadtree slices of an object without the use of an intermediate data structure. We also propose the d-slice, which is a generalization of an octree, and which efficiently represents non-cubic volumes.
N=2 W SUPERGRAVITY
Authors: BERGSHOEFF E. , DE ROO M.
Published: November 2004

We quantize the classical gauge theory of N=2 w∞ supergravity and show how the underlying N=2 super-w∞ algebra gets deformed into an N=2 super-W∞ algebra. Both algebras contain the N=2 super-Virasoro algebra as a subalgebra. We discuss how one can extract from these results information about quantum N=2 WN supergravity theories containing a finite number of higher-spin symmetries with superspin s≤N. As an example we discuss the case of quantum N=2 W3 supergravity.
MESON-DIQUARK LOOP EXPANSION
Authors: LUTZ M. , PRASCHIFKA J.
Published: November 2004

We consider a general (nonlocal) four-fermion quantum field theory and show how the Cornwall-Jackiw-Tomboulis effective action can be systematically expanded in the number, η, of composite, bose loops. This is achieved by the introduction of auxiliary, bilocal fields which describe fermion-fermion and fermion-antifermion correlations. The η expansion can be understood as a generalization of the [Formula: see text] expansion and is of particular interest in quark models, for example, where the bilocal fields can be identified with meson and diquark degrees of freedom. Comparison with the usual loop (ħ) expansion reveals some unusual characteristics of the η expansion and throws light on recent studies of diquark degrees of freedom in which the auxiliary field approach is used.
SM HIGGS BOSON HUNTING AT LEP
Authors: GROSS EILAM , YEPES PABLO
Published: November 2004

The best Higgs hunting machine ever built, LEP, started operation in the summer of 1989. Since then the mass region explored in searching for the Standard Model Higgs boson has been extended by more than an order of magnitude. An overview of the searches performed by the four LEP collaborations by the end of 1991 is presented.
11-DIMENSIONAL SUPERMEMBRANE IN A SPINOR MOVING REPERE FORMALISM
Authors: BANDOS I.A. , ZHELTUKHIN A.A.
Published: November 2004

Twistor-like formulations for super p-brane theories in the D-dimensional space-time including D=11 supermembrane are suggested in an extended configuration space. This extension is carried out by the addition of auxiliary spinor coordinates of the moving repere (the Newman-Penrose dyades for D=4). The spinor coordinates are realized as the Lorentz harmonics and necessary for the irreducible covariant description of the κ-symmetry. Using this harmonical realization a generalization of the Newman-Penrose dyades for the case D=11 is suggested.
HEAVY QUARK POLARIZATION AND ENERGY SPECTRA OF DECAY PRODUCTS IN SEMILEPTONIC DECAYS
Authors: MATSUMOTO SEIJI , TOMINAGA KENJI , TERAZAWA OSAMU , BIYAJIMA MINORU
Published: November 2004

We calculate in the free quark model energy distributions of final lepton and quark pairs from c and b quark semileptonic decays in e−e+ colliders. Polarizations and spin-spin correlations of heavy quark pair are discussed, which will test the vector and axial vector couplings of the Weinberg-Salam model especially near the Z peak.
INTERMITTENCY ANALYSIS OF FRAGMENTING NUCLEI WITH EXACT CONSERVATION LAWS
Authors: HAGLIN K. , GALE C. , GUPTA S. DAS
Published: November 2004

We show that the speculative charge bin size dependence of the scaled factorial moments for fragmenting nuclei in recent nuclear emulsion data may be attributed in part to simple conservation laws. Monte Carlo results from both the Thermodynamic Model and an Evaporation Model suggest that in such studies most or all of the effect is due to the fact that there exist constraints owing to conserved quantities.
FUSION RULES FROM ALGEBRAIC K-THEORY
Authors: RECKNAGEL ANDREAS
Published: November 2004

We show how quantum field theory fusion rules can be recovered from K0-groups of C*-algebras. Applying this method to certain AF algebras yields the fusion rules of SU(2)-WZW models.
THE RELATIVISTIC THEORY FOR PRINCIPAL TRAJECTORIES AND ELECTROMAGNETIC TRANSITIONS OF LIGHT MESONS PART I
Authors: BERDNIKOV E. B. , NANOBASHVILI G. G. , PRON'KO G. P.
Published: November 2004

Relativistic theory for the family of the principal meson trajectories was constructed. In the framework of relativistic quantum mechanics the coordinates of quarks should be noncommutative, which leads to a set of consistency conditions. Exploiting the geometrical basis of our model, we have obtained relativistic analogs of orbital and spin momenta and construct the gauge-invariant coordinates of physical particles. It makes possible to introduce the interaction terms in a simple geometrical way.
DYNAMICS OF MAGNETIC FIELDS IN MAXWELL, YANG–MILLS AND CHERN–SIMONS THEORIES ON THE TORUS
Authors: BURGESS MARK , McLACHLAN ALAN , TOMS DAVID J.
Published: November 2004

We reconsider the problem of uniform magnetic fields passing perpendicularly through a two-torus. We focus on dynamical effects from nonintegrable phases on the torus at nonzero B and from magnetic fields themselves in the vacuum. The spectrum is computed and is shown to be always independent of the nonintegrable phases on the torus. It is concluded that a Chern–Simons term will always be induced by radiative corrections to fermions on the torus when B ≠ 0. The special case of an electromagnetically uncharged anyon gas is noted and shown to be a system whose spectrum can depend on the nonintegrable phases in the two torus directions, subject to a consistency requirement. In three and four dimensions dynamical symmetry breaking of non-Abelian fields and associated condensate formation is possible by radiative corrections. The classification of non-Abelian magnetic fields in terms of "flux integers" is discussed, and a method for obtaining such integers for an arbitrary gauge algebra is presented which provides a rigorous generalization of 't Hooft's su(2) classification. Finally, we remark on the off-shell effective action in Chern–Simons theory.
NONLOCAL SEPARABLE SOLUTIONS OF THE INVERSE SCATTERING PROBLEM
Authors: GHERGHETTA TONY , NAMBU YOICHIRO
Published: November 2004

We extend the nonlocal separable potential solutions of Gourdin and Martin for the inverse scattering problem to the case where sin δ0 has more than N zeroes, δ0 being the s-wave scattering phase shift and δ0(0) − δ0(∞) = Nπ. As an example we construct the solution for the particular case of 4 He and show how to incorporate a weakly bound state. Using a local square well potential chosen to mimic the real 4 He potential, we compare the off-shell extension of the nonlocal potential solution with the exactly solvable square well. We then discuss how a nonlocal potential might be used to simplify the many-body problem of liquid 4 He .
SPECTRAL INVERSE PROBLEM IN SUPERSYMMETRIC QUANTUM MECHANICS
Authors: BERA P.K. , BHATTACHARYYA S. , TALUKDAR B.
Published: November 2004

The supersymmetric WKB quantization condition is used to study the so-called spectral inverse problem. Wavefunctions for the harmonic oscillator and hydrogen atom are obtained from the knowledge of their bound-state energy spectra. The analysis presented is based essentially on a repackaging of the conventional theory of integral equations.
A NEW APPROACH TO NONCOMPACT LATTICE QED WITH LIGHT FERMIONS
Authors: AZCOITI V. , CARLO G. DI , GRILLO A.F.
Published: November 2004

We discuss detailed simulations of the noncompact Abelian model coupled to light fermions, using a method previously developed that includes the effects of the fermionic interactions in an effective action. The approximations involved are related to an expansion in the flavor number. We address the problem of the (non)triviality of the theory through a study of the analytical properties of the effective action as a function of the pure gauge energy. New numerical results for the plaquette energy and the chiral condensate and a qualitative analysis of the phase diagram are also presented.
ISOSCALAR VECTOR BOSONS AT LEP II
Authors: GERSHTEIN S.S. , LIKHODED A.A. , OBRAZTSOV V.F. , SHEVLYAGIN M.V. , YUSHCHENKO O.P.
Published: November 2004

The phenomenological manifestations of the additional Y (YL) boson arising in the models with the composite structure of electroweak interactions are studied for the processes [Formula: see text] and e+e−→W+W− at the LEP II energies. It is shown that the inclusion of the additional isoscalar boson with the parameters providing the explanation for the TRISTAN data yields a measurable effect (~tens of per cent) in the cross-section of e+e−→µ+µ− (hadrons) processes at energies [Formula: see text]. A contribution of the additional boson in the cross-section of the e+e−→W+W− process is negligible (≤0.5%) at these energies.
EXACT WAVE FUNCTIONS OF MULTI-SPECIES ANYON QUANTUM MECHANICS
Authors: CHO K.H. , RIM CHAIHO , SOH D.S.
Published: November 2004

We investigate the many-anyon quantum-mechanical system of multi-species and obtain algebraically the energy and the angular momentum eigenstates in a harmonic potential well, in a constant magnetic field and of free system using ladder operators. The eigenvalues and their multiplicity of the eigenstates are given.
LOCALLY GAUGE-INVARIANT OFF-MASS-SHELL EFFECTIVE POTENTIAL IN QCD3 AND “HOT” QCD4
Authors: GUENDELMAN E.I. , OWEN D.A.
Published: November 2004

We develop a technique whereby we are able to excite the vacuum with external sources that are covariantly conserved even when quantum fluctuations are considered. This allows us to construct physical, gauge-invariant states and the corresponding gauge-invariant off-mass-shell effective potential corresponding to such states. To show a practical application of these ideas, we calculate for Euclidean QCD3 or “hot” QCD4, to one-loop order, the effective potential of a homogeneous, isotropic state where the gauge fields have a nonzero expectation value. The high temperature and possible cosmological consequences of our results are discussed. The definition of physically meaningful Green functions of any order, in an arbitrary space-time dimension, is discussed. In our formalism, in the presence of an external current, it is possible to define a BRS symmetry under which the effective Lagrangian is invariant and this allows one to define a physically meaningful effective potential.
MASSLESS FLOWS I: THE SINE-GORDON AND O(n) MODELS
Authors: FENDLEY P. , SALEUR H. , ZAMOLODCHIKOV AL. B.
Published: November 2004

The massless flow between successive minimal models of conformal field theory is related to a flow within the sine-Gordon model when the coefficient of the cosine potential is imaginary. This flow is studied, partly numerically, from three different points of view. First we work out the expansion close to the Kosterlitz-Thouless point, and obtain roaming behavior, with the central charge going up and down in between the UV and IR values of c=1. Next we analytically continue the Casimir energy of the massive flow (i.e. with real cosine term). Finally we consider the lattice regularization provided by the O(n) model in which massive and massless flows correspond to high- and low-temperature phases.

A detailed discussion of the case n=0 is then given using the underlying N=2 supersymmetry, which is spontaneously broken in the low-temperature phase. The “index” tr F(−1)F follows from the Painlevé III differential equation, and is shown to have simple poles in this phase. These poles are interpreted as occurring from level crossing (one-dimensional phase transitions for polymers). As an application, new exact results for the connectivity constants of polymer graphs on cylinders are obtained. These results and points of view are used in the following paper to discuss the appropriate exact S matrices and the resulting Casimir energies.
SPEECH-TO-TEXT CONVERSION IN FRENCH
Authors: GAUVAIN J.L. , LAMEL L.F. , ADDA G. , MARIANI J.
Published: November 2004

Speech-to-text conversion of French necessitates that both the acoustic level recognition and language modeling be tailored to the French language. Work in this area was initiated at LIMSI over 10 years ago. In this paper a summary of the ongoing research in this direction is presented. Included are studies on distributional properties of French text materials; problems specific to speech-to-text conversion particular of French; studies in phoneme-to-grapheme conversion for continuous, error-free phonemic strings; past work on isolated-word speech-to-text conversion; and more recent work on continuous-speech, speech-to-text conversion. Also demonstrated is the use of phone recognition for both language and speaker identification.

The continuous speech-to-text conversion for French is based on a speaker-independent, vocabulary-independent recognizer. In this paper phone recognition and word recognition results are reported evaluating this recognizer on read speech taken from the BREF corpus. The recognizer was trained on over 4 hours of speech from 57 speakers, and tested on sentences from an independent set of 19 speakers. A phone accuracy of 78.7% was obtained using a set of 35 phones. The word accuracy was 88% for a 1139 word lexicon and 86% for a 2716 word lexicon, with a word pair grammar with respective perplexities of 100 and 160. Using a bigram grammar, word accuracies of 85.5% and 81.7% were obtained with 5 K and 20 K word vocabularies, with respective perplexities of 122 and 205.
AN EVALUATION OF PARALLEL STRATEGIES FOR FEATURE VECTOR CONSTRUCTION IN AUTOMATIC SIGNATURE VERIFICATION SYSTEMS
Authors: FAIRHURST M.C. , BRITTAN P.
Published: November 2004

This paper describes possible strategies for the implementation of a feature selection algorithm particularly suited to the realisation of an efficient automatic handwritten signature verification system in which an active feature vector, optimised with respect to an individual signer, is constructed during an enrollment period. A range of configurations based on transputer arrays are considered and the possible implementational approaches evaluated. The paper demonstrates how the inherent parallelism which exists within a generic model for verification can be exploited to provide an optimised general-purpose framework for verification processing.
HANDPRINTED CHINESE CHARACTER RECOGNITION USING THE PROBABILITY DISTRIBUTION FEATURE
Authors: LI TZE FEN , YU SHIAW-SHIAN
Published: November 2004

A simplified Bayes rule is used to classify 5401 categories of handwritten Chinese characters. The main feature for the Bayes rule deals with the probability distribution of black pixels of a thinned character. Our idea is that each Chinese character indicated by the black pixels represents a probability distribution in a two-dimensional plane. Therefore, an unknown pattern is classified into one of 5401 different distributions by the Bayes rule. Since the handwritten character has an irregular shape variation, the whole character is normalized and then thinned. Finally, a transformation is used to spread the black pixels uniformly over the whole square plane, but it still keeps the relative positions of the original black pixels. The main feature gives an 88.65% recognition rate. In order to raise the recognition rate, 4 more subsidiary features are elaborately selected such that they are not affected much by the irregularly shaped variation. The 4 features raise the recognition rate to 93.43%. A 99.30% recognition rate is achieved if the top 10 categories of HCC are selected by our recognition method and 99.61% if the top 20 are selected.
FEATURE EXTRACTION AND MATCHING AS SIGNAL DETECTION
Authors: HU XIAOPING , AHUJA NARENDRA
Published: November 2004

This paper discusses detection and matching of arbitrary image features or patterns. The common characteristics of feature extraction and matching are summarized which show that they can be considered as special cases of a more general problem—signal detection. However, the existing signal detection theories do not solve feature extraction and matching problems readily. Therefore, a general formulation of feature extraction and matching as a problem of signal detection is presented. This formulation unifies feature extraction and matching into a more general framework so that the two can be better integrated to form an automatic system for image matching or object recognition. Following this formulation, guidelines for designing algorithms for detection or matching of arbitrary image features or patterns which can be easily implemented or reconfigurated for many practical applications are derived. Sample algorithms resulting from this formulation and the associated experimental results with real image data are provided which demonstrate the performance and robustness of the methods.
A FOUR DEGREE-OF-FREEDOM ROBOT HEAD FOR ACTIVE VISION
Authors: DU FENGLEI , BRADY MICHAEL
Published: November 2004

The design of a robot head for active computer vision tasks is described. The stereo head/eye platform uses a common elevation configuration and has four degree-of-freedom. The joints are driven by DC servo motors coupled with incremental optical encoders and backlash minimizing gearboxes. The details of mechanical design, head controller design, the architecture of the system, and the design criteria for various specifications are presented.
FAST AND ACCURATE TIME-DOMAIN ANALYSIS OF PIECEWISE-LINEAR DYNAMICS CIRCUITS: THE COMPUTER PROGRAM PILA
Authors: BIEY MARIO , HASLER MARTIN , LOJACONO ROBERTO , PREMOLI AMEDEO
Published: November 2004

The computer program PILA (piecewise-linear analysis) is described. It is specially designed for exploring complicated dynamics of moderately sized piecewise-linear circuits. The DC-analysis is performed either by an adapted version of Katzenelson’s algorithm or by an algorithm designed for solving the linear complementarity problem. If the user chooses the latter algorithm, he will get all solutions of the DC-problem, whereas with Katzenelson’s algorithm usually just one solution is found. The time-domain analysis proceeds by the calculation of eigenvalues of the state matrix in order to obtain a time-symbolic solution in each linear region. This method is particularly fast and accurate, as long as the order of the circuit is not too high. The main errors occur in the determination of the transition between two adjacent linear regions. Particular care has been taken to get maximum transition accuracy. Some examples illustrate the various features of PILA.
DESIGN OF REDUNDANT FORMAL SPECIFICATIONS BY LOGIC PROGRAMMING: MERGING FORMAL TEXT AND GOOD COMMENTS
Authors: RENAULT SOPHIE , DERANSART PIERRE
Published: November 2004

Among the various tasks involved in SE & KE, requirements engineering, specification, prototyping, and validation are regarded as crucial since they decide whether a software system fulfills the users’ expectations. Formal methods provide a rigorous framework to guaranteed. Logic Programming has been recently shown as a promising candidate support these tasks and some relevant features can be in that way captured and formally regarding these concerns. Nevertheless, formalism does need some explanation to let it be more readable and understandable.

This paper focuses on a specification design method which mixes formal text (represented by a logic program) and comments (using either formal or informal assertions). By the design of a specification we refer to the intertwined tasks of describing the specification and improving it by the investigation of proofs. These proofs aim to verify the link between the specification and the comments, and are partly automated. Then we present our practical experience in the use of an interacti ve proof system. As an example, we show how this methodology is currently applied to the draft of standard Prolog.
COMPUTATIONAL GEOMETRY COLUMN 23
Authors: O'ROURKE JOSEPH
Published: November 2004

Three open problems on tetrahedralizations are described: Does bisection refinement keep solid angles bound away from zero? Can a tetrahedralization be frozen with respect to flips? Do points in convex position have a Hamiltonian tetrahdralization?
IMPLICIT POINT LOCATION IN ARRANGEMENTS OF LINE SEGMENTS, WITH AN APPLICATION TO MOTION PLANNING
Authors: AGARWAL PANKAJ K. , VAN KREVELD MARC
Published: November 2004

Let [Formula: see text] be a set of n (possibly intersecting) line segments in the plane. We show that the arrangement of [Formula: see text] can be stored implicitly in a data structure of size O(n log 2n) so that the following query can be answered in time O(n1/2 log 2 n): Given two query points, determine whether they lie in the same face of the arrangement of S and, if so, return a path between them that lies within the face. This version of the implicit point location problem is motivated by the following motion planning problem: Given a polygonal robot R with m vertices and a planar region bounded by polygonal obstacles with n vertices in total, preprocess them into a data structure so that, given initial and final positions of R, one can quickly determine whether there exists a continuous collision-free translational motion of R from the initial to the final position. We show that such a query can be answered in time O((mn)1/2 log 2 mn) using O(mn log 2 mn) storage.
REDUCED FACTORIZATIONS IN FREE PROFINITE GROUPS AND JOIN DECOMPOSITIONS OF PSEUDOVARIETIES
Authors: ALMEIDA JORGE , WEIL PASCAL
Published: November 2004

In this paper we investigate certain notions from the theory of free profinite groups, which we then apply to the study of certain pseudovarieties of monoids. More precisely, the profinite Cayley graphs of the free pro-H groups are H-trees for certain, so-called arborescent, pseudovarieties of groups H. For such pseudovarieties, we introduce the notion of reduced factorizations in the free pro-H groups, and we prove that these factorizations enjoy a common refinement property. This property, in turn, is used to compute joins of certain pseudovarieties of monoids with pseudovarieties of groups within the pseudovariety DS of all finite monoids in which each regular [Formula: see text]-class is a subsemigroup. We then apply our results to the theory of formal languages.
FREQUENCY DOUBLING FROM A NOVEL ORGANIC CRYSTAL
Authors: SASAKI K. , KINOSHITA T. , HORINOUCHI S. , YAMAKAWA S. , TANAKA N. , OKAMOTO H.
Published: November 2004

A novel optical nonlinear organic crystal: 2-Furyl-Methacrylic Anhideride(FMA) was grown by solution method. The crystal belongs to the 4 mm of point group and is optically uniaxial. Non-zero SHG coefficients for frequency doubling were d33=24 pm/V and d31=16 pm/V respectively. The polished bulk crystal was used for frequency doubling at type II phase matching. And also the crystal was utilized as nonlinear optical substrate of an SHG waveguide.
Z-SCAN AND EZ-SCAN MEASUREMENTS OF OPTICAL NONLINEARITIES
Authors: XIA T. , SHEIK-BAHAE M. , SAID A.A. , HAGAN D.J. , VAN STRYLAND E.W.
Published: November 2004

We describe the application of single beam propagation methods, namely Z-scan and EZ-scan, for the determination of nonlinear refractive indices in materials including thin films. In these experiments the transmittance of a sample is measured either through a finite aperture (Z-scan) or around an eclipsing disk (EZ-scan) placed in the far-field as the sample is moved along the propagation path (Z) of a focused beam. Both methods can also be used to separately measure the nonlinear absorption so that both the real and imaginary parts of the nonlinear susceptibility are determined along with their signs. The sensitivity to induced phase distortion depends on the sensitivity of the measuring apparatus to transmittance changes ΔT. For the 10 Hz repetition rate Nd:YAG lasers used in our experiments, we can detect ΔT≃10−3. This leads to a sensitivity to optical path length changes of λ/103 for the Z-scan and λ/104 for the EZ-scan where λ is the wavelength. This interferometric sensitivity, using a single beam, allows measurement of nonlinear refraction in thin films without the need for using a waveguiding geometry.
A TASK PLANNER FOR INTELLIGENT MOBILE ROBOTS USING SUBGOAL PRIORITY INFORMATION
Authors: XUE Q. , CHIEN Y.P. , FENG YUANLI , PALAKAL M.J.
Published: November 2004

We have developed a fast task planner for intelligent mobile robots. The speed gain of this task planner over traditional task planners is achieved by avoiding goal-interaction and by utilizing a parallel comparison network. Goal-interaction during task planning is avoided by executing subgoals in a depth first fashion according to the priority numbers attached to subtasks and preconditions of the robot operations in the rule base. The assignment of these priority numbers is based on spatial relationship between objects in the robot environment and time sequence of the subtasks. A combination of hardware circuits and software program is used to search proper robot operations in parallel. Special problems encountered in the design of this task planner are discussed and examples are given to demonstrate the advantages of this task planner. This study provides a new approach which significantly increases the speed of robot task planning.
THE PROBLEM OF PARTITIONING WITH DUPLICATIONS AND ITS APPLICATIONS
Authors: HARALAMBIDES J. , TRAGOUDAS S.
Published: November 2004

The problem of partitioning the elements of a graph G=(V, E) into two equal size sets A and B that share at most d elements such that the total number of edges (u, v), u∈A−B, v∈B−A is minimized, arises in the areas of Hypermedia Organization, Network Integrity, and VLSI Layout. We formulate the problem in terms of element duplication, where each element c∈A∩B is substituted by two copies c′∈A and c″∈B As a result, edges incident to c′ or c″ need not count in the cost of the partition. We show that this partitioning problem is NP-hard in general, and we present a solution which utilizes an optimal polynomial time algorithm for the special case where G is a series-parallel graph. We also discuss special other cases where the partitioning problem or variations are polynomially solvable.
LOCATION-INDEPENDENT TRANSFORMATIONS: A GENERAL STRATEGY FOR IMPLEMENTING NEURAL NETWORKS
Authors: RUDOLPH GEORGE L. , MARTINEZ TONY R.
Published: November 2004

Most Artificial Neural Networks (ANNs) have a fixed topology during learning, and typically suffer from a number of short-comings as a result. Variations of ANNs that use dynamic topologies have shown ability to overcome many of these problems. This paper introduces Location-Independent Transformations (LITs) as a general strategy for implementing neural networks that use static and dynamic topologies. A LIT creates a set of location-independent nodes, where each node computes its part of the network output independent of other nodes, using local information. This type of transformation allows efficient support for adding and deleting nodes dynamically during learning. Two simple networks, the single-layer competitive learning network, and the counterpropagation network, which combines elements of supervised learning with competitive learning, are used in this paper to illustrate the LIT strategy. These two networks are localist in the sense that ultimately one node is responsible for each output. LITs for other models are presented in other papers.
ON THE INDEX OF GRAPHS: INDEX VERSUS CYCLE INDEX
Authors: TRACZYK PAWEL
Published: November 2004

We study the relation between the two notions of index of graphs defined in [1]. We show that in the geometrically significant context of bipartite graphs the two coincide.
HOMOGENEOUS LINEAR FUZZY FUNCTIONS AND RANKING METHODS IN FUZZY LINEAR PROGRAMMING PROBLEMS
Authors: HERRERA F. , VERDEGAY J. L. , KOVÁCS M.
Published: November 2004

A general model for Fuzzy Linear Programming problem is studied. Fuzzy numbers generated by an homogeneous linear fuzzy function have been used for representing the imprecision of the parameters. A solution method is proposed using fuzzy numbers ranking procedures.
CONSTRAINTS AS INCOMPATIBILITY RELATIONS IN KBS
Authors: CASTRO J. L. , TRILLAS E.
Published: November 2004

In this paper we will show that the different definitions of contradiction obtained in the literature can be modeled by means of an incompatibility relation.
REPRESENTING CONDITIONAL INDEPENDENCE RELATIONS BY VALUATION NETWORKS
Authors: SHENOY PRAKASH P.
Published: November 2004

Valuation networks have been proposed as graphical representations of valuation-based systems. The axiomatic framework of valuation-based systems is able to capture many uncertainty calculi including probability theory, Dempster-Shafer's belief-function theory, Spohn's epistemic belief theory, and Zadeh's possibility theory. In this paper, we show how valuation networks encode conditional independence relations. For the probabilistic case, the class of probability models encoded by valuation networks includes undirected graph models, directed acyclic graph models, directed balloon graph models, and recursive causal graph models.
APPLICATION OF IDENTIFICATION OF FUZZY MODEL IN STRUCTURAL MECHANICS
Authors: MENG HSIEN-KANG , CHIANG WEI-LING
Published: November 2004

In the conventional analysis of structural mechanics, the structural behaviour are determined in mathematical functions and based on idealized assumptions. But structural members do not behaviour as the description of the mathematical functions if the system is too complicated. Consequently, we don't have an appropriate methodology and an convenient algorithm to utilize.

If we identify the structural system with a fuzzy model, [Formula: see text], where [Formula: see text] is the fuzzy relation, the procedure of the system identification will be simplified and the model can be quickly constructed 110 matter the style of nonlinear form and the orders.

In this paper, four composition operators (α, β, φ and t) will be used to derive fuzzy relations from given data and then applied to two interesting problems of structural mechanics for illustrating the reliability ty and efficiency of the theory of fuzzy model.
CALCULATING MAXIMUM-ENTROPY PROBABILITY DENSITIES FOR BELIEF FUNCTIONS
Authors: MEYEROWITZ AARON , RICHMAN FRED , WALKER ELBERT
Published: November 2004

A common procedure for selecting a particular density from a given class of densities is to choose one with maximum entropy. The problem addressed here is this. Let S be a finite set and let B be a belief function on 2S. Then B induces a density on 2S, which in turn induces a host of densities on S. Provide an algorithm for choosing from this host of densities one with maximum entropy.
THE INVERSE PROBLEM OF THE AGGREGATION OF FUZZY SETS
Authors: ARNOULD THIERRY , TANO SHUN'ICHI
Published: November 2004

The inverse problem of the aggregation of fuzzy sets is addressed: the result of the aggregation of several fuzzy sets being known, the aim is to determine the initial sets. The case of the aggregation of two premises is studied first and a rule-based method is proposed to determine exactly all the widest solution sets of the problem. A recurrent algorithm is then proposed to solve the problem in the case of any number of fuzzy sets. The relevance of the proposed criteria enables to cope with the exponential complexity of the problem, and to define the widest solution sets only. Examples are provided to illustrate how the solving algorithms can practically be applied.
MATHEMATICAL VISUALIZATION AND ANALYSIS TECHNIQUES FOR ENTREPRENEURSHIP STUDIES: IMAGE PROCESSING IN THE UNITED STATES, EUROPE, JAPAN AND AUSTRALIA
Authors: ALONSO JOSE , BYGRAVE W , GILLIN L M
Published: November 2004

Statistics and computer graphics, using linear and non-linear techniques, have been applied to entrepreneurial survey data in a study of the image analysis industry. Chief Executive Officers and Directors of Research have been interviewed in the United States, Europe, Japan and Australia. During the interview, a long questionnaire was completed. A mathematical model in terms of motivation, resources and performance measures has been developed to evaluate company positioning, and for future implementation as an expert system for high technology investment evaluation.

A set of indices, derived using cluster and principal component analyses, describes groupings of variables which can be used to find the locus of a company position in an n-dimensional space. This position helps to establish whether the requisite technical, knowledge, marketing and financial infrastructures of the company are in keeping with the n-dimensional surfaces established by other companies in the field. These surfaces are then visualized using polynomial and Fourier parametric methods. Stratifications of the database by culture (as determined by geographical location), manufacturer-user-integrator classification, measures of innovation, and modes of deployment of financial resources are studied in terms of their taxonomic and performance characterisation abilities. Preliminary analyses reveal noticeable clustering of motivational variables by culture.
BUILDING AN ENTREPRENEURIAL MINDSET IN YOUNG CHILDREN IN SINGAPORE
Authors: SHARPE PAMELA
Published: November 2004

This paper points to some qualitative differences in the developing child and the research which has indicated that entrepreneurial behaviour is socially acquired. It will be argued that the importance of parental and family influences on shaping children’s behaviour and thinking processes is crucial, given certain conditions including parental attitudes, support, control and reinforcement. Additionally, it will be evident that the success of such influences depends very much on the child as an individual, and the degree to which parenting practices match developmental levels.
ML ESTIMATES FOR CROW/AMSAA RELIABILITY GROWTH MODEL FOR GROUPED AND MIXED TYPES OF SOFTWARE FAILURE DATA
Authors: RANI  , MISRA R. B.
Published: November 2004

A number of software reliability growth models have been proposed into the literature for estimating reliability during software testing. Duane's model,7 originally proposed for hardware reliability is also used in estimating reliability of the software during development testing. Graphical interpretation of Duane's postulate subsequently was given a concrete stochastic basis by Crow,3 and provided a comprehensive treatment of this model in the context of reliability growth and demonstrated its elegant inferential aspects. Parameters of the Crow model have physical interpretation and can yield quantitative measure for reliability growth assessment. This paper proposes a simple and efficient procedure to determine parameters of Crow/AMSAA model using one dimensional bisection method for grouped/interval data, where failures are recorded at various time points. In addition this paper proposes a method to estimate parameters when there exist a mixture of grouped and individual (mixed or hybrid) data types. Proposed method's application is illustrated with numerical examples using both simulated and real software failure data.
OPTIMIZING SPARE PARTS STORAGE POLICY BASED ON AVAILABILITY DESIGN
Authors: KUO WAY , RAHMAN M.
Published: November 2004

This study uses a tool to evaluate the performance of flexible manufacturing systems (FMS) on the basis of both conventional design parameters — mean time to failure, mean time to repair, and mean time to replacement — and other factors, including the use of the Markov process. System effectiveness is used as a performance measure, and credits are granted if only some of the systems are functional. To improve performance, the researchers installed a central storage area, whose inventory of spares is optimized heuristically, to replenish spares for failing equipment. In this paper, a heuristic approach is presented to optimize the number of spare parts used in a central storage area. Such a heuristic method along with a performance measure is likely to be very useful for most real-life FMS environments. As given in an example, the model can be tested for a wide range of applications.