bluuebunny/crossref_metadata_2025 huggingface dataset:
Emptiness of the left iliac fossa: a new clinical sign of sigmoid volvulus
Authors: Raveenthiran V
Published: July 2002

Background

Diagnostic difficulties are common in sigmoid volvulus. This diagnostic delay contributes to high morbidity and mortality.

Aim

This paper recognises visible or palpable emptiness of the left iliac fossa as a new clinical sign of sigmoid volvulus. Predictive accuracy of the sign was assessed in this study.

Methods

519 patients with acute abdomen of non-traumatic origin were prospectively studied.

Results

The new sign was present in 24 out of 86 patients (28%) with sigmoid volvulus. It was absent in all those who did not have sigmoid volvulus. The positive predictive value of the sign was 100%.

Conclusion

Emptiness of the left iliac fossa is a valuable diagnostic adjunct. Positive sign is pathognomonic of sigmoid volvulus. Nevertheless, a negative sign warrants further investigations.
Some high pitched thoughts on chest examination
Authors: Welsby P D , Earis J E
Published: July 2002

Observation reveals that about half of chest physicians use the stethoscope bell when auscultating the lungs and the other half use the diaphragm. None directly apply their ears. Despite extensive reading we have not encountered an evidence based answer to the question “Should normal mortals use the bell or diaphragm?” This unanswered question thus prompted an acoustical odyssey.
Efficiency of three PCR-based markers in assessing genetic variation among cowpea (Vigna unguiculatasubsp.unguiculata) landraces
Authors: Tosti Nicola , Negri Valeria
Published: July 2002

The main objective of this study was to investigate the efficiency of RAPD, AFLP, and SAMPL marker systems in detecting genetic polymorphism in cowpea landraces (Vigna unguiculata subsp. unguiculata (L.) Walp.) that probably share a similar genetic pool. A second objective was to determine the level of diversity among landraces from a restricted area, to define the most appropriate strategy of on-farm conservation. Each marker system was able to discriminate among the materials analysed, but a clear distinction between all the local varieties was only obtained with AFLP and SAMPL markers. The average diversity index was quite similar for each marker system, but owing to the differences in the effective multiplex ratio values the marker index was higher for the AFLP and SAMPL systems than for the RAPD system. The AFLP and SAMPL techniques appear to be more useful than the RAPD technique in the analysis of limited genetic diversity among the cowpea landraces tested. The significant correlations of SAMPL similarity and cophenetic matrices with those of the other markers, and the lower number of primer combinations required, indicate that this technique is the most valuable. The low genetic similarity detected among landraces suggests that all the cowpea landraces should be maintained on the respective farms from which they came.Key words: landraces, molecular marker, marker index, Vigna.
Efficacité du pré-signalement d'arrêt scolaire avec feux jaunes et avec feux de détresse
Authors: Bruneau Jean-François , Morin Denis , Pouliot Marcel
Published: July 2002

The pre-stop warning is activated by the bus drivers to warn motorists that the school bus will soon stop, requiring all vehicles to stop. On buses equipped with an eight-light system, four yellow flashing lights, located near the roof, precede the four red flashing lights activated with the stop-arm. In Québec, where pre-stop warning is not required, it is permitted to use the "hazard lights" as a pre-stop signal, when the school bus has red lights only. This study rates the relative effectiveness of the two systems, in fall and spring time. Advance signal lights are tested on the same routes : two- and four-lane rural or near urban highways, with high posted speeds (70 km/h and over). A video camera is aimed at oncoming traffic along with a radar antenna. Changes in drivers' speeds are studied with a relative risk ratio and an efficiency index, validated through expected frequencies. The eight-light system reduced significantly the rate of illegal passing and the overall speed during advance signal. The eight-light system was more effective than the hazard lights for all tested parameters, including visibility, traffic, weather, and season. The near-roof position of the yellow lights probably explains the gap between the two systems.Key words: advance signalling device, pre-stop warning, eight-light system, amber lights, hazard lights, school buses, illegal passing, speed, relative risk ratio, road safety, rural area.
Inhibition of angiogenesis by two-chain high molecular weight kininogen (HKa) and kininogen-derived polypeptides
Authors: Zhang Jing-Chuan , Qi Xiaoping , Juarez Jose' , Plunkett Marian , Donaté Fernando , Sakthivel Ramasamy , Mazar Andrew P , McCrae Keith R
Published: July 2002

We recently reported that the two-chain form of human high molecular weight kininogen (HKa) inhibits angiogenesis by inducing endothelial cell apoptosis (Zhang et al. 2000). This property appears to be primarily conferred by HKa domain 5 (HKa D5). In this manuscript, we further characterize the activity of these polypeptides toward proliferating endothelial cells, as well as their in vivo anti-angiogenic activity in the chick chorioallantoic membrane (CAM). We also demonstrate that short peptides derived from endothelial cell binding regions in HKa domains 3 and 5 inhibit endothelial cell proliferation and induce endothelial cell apoptosis. Like HKa and HKa D5, peptides derived from the latter domain induce endothelial cell apoptosis in a Zn2+-dependent manner, while those derived from domain 3 function independently of Zn2+. The implications of these findings to the regulation of angiogenesis and development of anti-angiogenic therapeutics are discussed.Key words: angiogenesis, kininogen, endothelial cells, apoptosis, peptides.
SUPERSELECTION SECTORS WITH BRAID GROUP STATISTICS AND EXCHANGE ALGEBRAS II: GEOMETRIC ASPECTS AND CONFORMAL COVARIANCE
Authors: FREDENHAGEN KLAUS , REHREN KARL-HENNING , SCHROER BERT
Published: July 2002

The general theory of superselection sectors is shown to provide almost all the structure observed in two-dimensional conformal field theories. Its application to two-dimensional conformally covariant and three-dimensional Poincaré covariant theories yields a general spin-statistics connection previously encountered in more special situations. CPT symmetry can be shown also in the absence of local (anti-) commutation relations, if the braid group statistics is expressed in the form of an exchange algebra.
RADIATIVE DECAY: NONPERTURBATIVE APPROACHES
Authors: HÜBNER MATTHIAS , SPOHN HERBERT
Published: July 2002

In radiative decay the coupled system, electron bound by some external potential plus radiation field, relaxes to the ground state in the long time limit. Our central issue is to prove such a behaviour on the basis of the corresponding Schrödinger equation. We argue that the spin-boson Hamiltonian is a simple, but physically still acceptable test case. We relate radiative decay to scattering theory and prove the existence of wave operators. Other approaches are reviewed and compared. Some challenging open problems are listed.
CANONICAL QUANTIZATION OF YANG-MILLS ON A CIRCLE
Authors: DIMOCK J.
Published: July 2002

The canonical quantization of YM on a circle in the temporal gauge is developed in two different mathematically rigorous formulations. In the first case the basic coordinates are the gauge potentials and we give a complete construction, but find no observables. In the second case the basic coordinates are the holonomy operators (Wilson loop operators) and here we also give a construction. A key ingredient is a proof that the irreducible characters of the holonomy operators are eigenvectors for the Hamiltonian.
Geometric Realizations of Representations of Finite Length
Authors: Conley Charles H.
Published: July 2002

Let G=H×ℝn be a semidirect product Lie group. We reduce the problem of deciding which indecomposable representations of G may be realized in subquotients of spaces of sections of vector bundles over infinitesimal neighborhoods of orbits of H in the dual of ℝn to a problem involving only representations of the H-stabilizers of the orbits.
Masslessness in n-Dimensions
Authors: Angelopoulos Eugenios , Laoues Mourad
Published: July 2002

We determine the representations of the "conformal" group [Formula: see text], the restriction of which on the "Poincaré" subgroup [Formula: see text] are unitary irreducible. We study their restrictions to the "De Sitter" subgroups [Formula: see text] and [Formula: see text] (they remain irreducible or decompose into a sum of two) and the contraction of the latter to "Poincaré". Then we discuss the notion of masslessness in n dimensions and compare the situation for general n with the well-known case of 4-dimensional space-time, showing the specificity of the latter.
QUANTUM NOETHER'S THEOREM AND CONFORMAL FIELD THEORY: A STUDY OF SOME MODELS
Authors: CARPI SEBASTIANO
Published: July 2002

We study the problem of recovering Wightman conserved currents from the canonical local implementations of symmetries which can be constructed in the algebraic framework of quantum field theory, in the limit in which the region of localization shrinks to a point. We show that, in a class of models of conformal quantum field theory in space-time dimension 1+1, which includes the free massless scalar field and the SU(N) chiral current algebras, the energy-momentum tensor can be recovered. Moreover we show that the scaling limit of the canonical local implementation of SO(2) in the free complex scalar field is zero, a manifestation of the fact that, in this last case, the associated Wightman current does not exist.
BENCHMARKING CLUSTERS OF WORKSTATIONS THROUGH PARALLEL SORTING AND BSP LIBRARIES
Authors: CÉRIN CHRISTOPHE , GAUDIOT JEAN-LUC
Published: July 2002

We present our experiences in developping and tuning the performance at the user level, of (in core) parallel sorting on homogeneous and non homogeneous clusters with the use of the two available BSP (Bulk Synchronous Parallel model) libraries: BSPLib from Oxford university (UK) and PUB7 from the university of Paderborn (Germany). The paper is mainly about the communication performances of these two libraries and, in more general terms, it compares and summarizes the programming facilities and differences between them.
Inhibitory Effect of Carthamus tinctorius L. Seed Extracts on Bone Resorption Mediated by Tyrosine Kinase, COX-2 (cyclooxygenase) and PG (prostaglandin) E2
Authors: Yuk Tae Han , Kang Joon Hyeog , Lee San Ryoung , Yuk Sang Won , Lee Kwang Gyu , Song Beum Yong , Kim Cheorl Ho , Kim Dong Wook , Kim Dong Il , Lee Tae Kyun , Lee Chang Hyun
Published: July 2002

Anti-bone resorption properties of the Korean herbal formulation, Honghwain (HHI; Carthamus tinctorius L. seed) was biochemically investigated. On processing bone metabolism, PGE2 accelerated production of IL-1β in fetal mouse osteoblast and stimulated physiological activation substance, IL-1β. The novel class of Src tyrosine kinase inhibitors, Herbimycin A (HERB) and HHI reduced COX-2 mRNA levels as well as PGE2 production induced by IL-1β, TNF-α and IL-6. HHI inhibited in vitro and in vivo bone resorption by inhibition of phosphorylation of peptide substrates. HHI dose-dependently reduced the hypercalcemia induced in mice by IL-1β and partly prevented bone loss and microarchitectural changes in young ovariectomized rats, showing that the protective effect on bone was exerted via the inhibition of bone resorption. These results indicate that the synergy between IL-β, TNF-α, IL-6 on PGE2 production is due to an enhanced gene expression of COX-2 and that tyrosine kinase (s) are involved in the signal transduction of COX-2 in mouse calvarial osteoblasts. Thus, HHI as a possible Src family kinase inhibitor may be useful for the treatment of diseases associated with elevated bone loss.
Computer Automated Prediction of Potential Therapeutic and Toxicity Protein Targets of Bioactive Compounds from Chinese Medicinal Plants
Authors: Chen Y. Z. , Ung C. Y.
Published: July 2002

Understanding the molecular mechanism and pharmacology of bioactive compounds from Chinese medicinal plants (CMP) is important in facilitating scientific evaluation of novel therapeutic approaches in traditional Chinese medicine. It is also of significance in new drug development based on the mechanism of Chinese medicine. A key step towards this task is the determination of the therapeutic and toxicity protein targets of CMP compounds. In this work, newly developed computer software INVDOCK is used for automated identification of potential therapeutic and toxicity targets of several bioactive compounds isolated from Chinese medicinal plants. This software searches a protein database to find proteins to which a CMP compound can bind or weakly bind. INVDOCK results on three CMP compounds (allicin, catechin and camptotecin) show that 60% of computer-identified potential therapeutic protein targets and 27% of computer-identified potential toxicity targets have been implicated or confirmed by experiments. This software may potentially be used as a relatively fast-speed and low-cost tool for facilitating the study of molecular mechanism and pharmacology of bioactive compounds from Chinese medicinal plants and natural products from other sources.
NONCLASSICAL STATE REPRESENTATION OF INFLATON AND POWER-LAW EXPANSION IN FRW UNIVERSE
Authors: SURESH P. K.
Published: July 2002

We have examined a homogeneous massive scalar field minimally coupled to the spatially flat Friedmann–Robertson–Walker metric, in squeezed and coherent state formalisms, in semiclassical theory of gravity. In the oscillatory phase of inflaton, the approximate leading solution to the semiclassical Einstein equation has the same power-law expansion as that of the classical Einstein equation for both coherent and squeezed state formalisms. Quantum fluctuations of the inflaton in coherent and squeezed vacuum states are studied, by using dispersion relations. The uncertainty relation for coherent state does not depend on the coherent state parameter while the uncertainty relation for squeezed vacuum state depends on the associated squeezing parameter and squeezing angle.
SEARCH FOR A STANDARD EXPLANATION OF THE PIONEER ANOMALY
Authors: ANDERSON JOHN D. , LAU EUNICE L. , TURYSHEV SLAVA G. , LAING PHILIP A. , NIETO MICHAEL MARTIN
Published: July 2002

The data from Pioneer 10 and 11 shows an anomalous, constant, Doppler frequency drift that can be interpreted as an acceleration directed towards the Sun of aP = (8.74 ± 1.33) × 10-8 cm / s 2. Although one can consider a new physical origin for the anomaly, one must first investigate the contributions of the prime candidates, which are systematics generated on board. Here we expand upon previous analyses of thermal systematics. We demonstrate that thermal models put forth so far are not supported by the analyzed data. Possible ways to further investigate the nature of the anomaly are proposed.
A TIME-OF-FLIGHT DETECTOR FOR CDF
Authors: GROZIS C. , KEPHART R. , STANEK R. , KIM B. , KIM D. H. , KIM S. B. , Oh Y. , YU I. , KIM Y. K. , CARITHERS W. , ANIKEEV K. , BAUER G. , FURIĆ I. K. , KRAVCHENKO I. , MULHEARN M. , PAUS CH. , SUMOROK K. , CABRERA S. , FERNANDEZ J. , PIEDRA J. , RODRIGO T. , RUIZ A. , VILA I. , CHEN C. , JONES M. , KONONENKO W. , KROLL J. , MAYERS G. M. , NEWCOMER F. M. , USYNIN D. , VANBERG R. , BELLETTINI G. , CERRI C. , MENZIONE A. , DEPEDIS D. , DIONISI C. , GIAGU S. , RESCIGNO M. , ZANELLO L. , KAZAMA A. , KIM S. H. , MATSUNAGA H. , MOTOHASHI S. , SATO K. , TAKIKAWA K. , UKEGAWA F.
Published: July 2002

A Time-of-Flight detector (TOF), with a technique based on plastic scintillators and finemesh photomultipliers, has been added to the CDF-II experiment. The main physics motivation is to improve neutral B meson flavor determination by K± identification. The expected time resolution is 100 ps, which provides at least two standard deviations separation between K± and π± for momenta p < 1.6 Gev/cand better than 1.2 standard deviations separation over all momenta when combining TOF identification with dE/dx identification using the new drift chamber.
PRODUCTION, SPECTROSCOPY AND DECAY OF ORBITALLY EXCITED B MESONS
Authors: GAGNON PAULINE
Published: July 2002

This paper reviews the most recent results from LEP and the Tevatron on production rates, masses and widths of orbitally excited B meson states. It also provides possible explanations for the various discrepancies observed between some of these experimental results.
ROBUST CHAOS IN A SMOOTH SYSTEM
Authors: ANDRECUT M. , ALI M. K.
Published: July 2002

Robust chaos is defined by the absence of periodic windows and coexisting attractors in some neighborhood of the parameter space. The occurrence of robust chaos has been discussed [Phys. Rev. Lett.78, 4561 (1997); ibid.80, 3049 (1998)]. It has been shown that robust chaos can occur in piecewise smooth systems. Also, it has been conjectured that robust chaos cannot occur in smooth systems. However, here we give a counter example to this conjecture. We present a one-dimensional smooth map xt + 1 = f(xt, α) that generates robust chaos in a large domain of the parameter space (α). An application to random number generation and cryptography is also presented.
THEORY OF PHOTOINDUCED PHASE TRANSITION IN THE QUASI-ONE-DIMENSIONAL CHARGE TRANSFER COMPOUND TTF-CA
Authors: HUAI P. , NASU K.
Published: July 2002

We theoretically study the photoinduced ionic→neutral phase transition in the quasi-one-dimensional molecular crystal TTF-CA. Our theoretical model includes strong intra-chain Coulomb interactions as well as very weak inter-chain interactions. Within the mean-field picture, we investigate the nonlinear lattice relaxation of a charge transfer exciton, and clarify the adiabatic path from its Franck-Condon state to a macroscopic neutral domain. It is found that the lowest state of such a single charge transfer exciton can not relax down to the neutral domain straightly, but a large excess energy is necessary so that it can overcome a high barrier. The aggregation of two identically shaped neutral domains is also discussed.
THE ORIENTATIONAL POTENTIAL IN SOLID C60
Authors: CHAPLOT S. L. , PINTSCHOVIUS L.
Published: July 2002

Numerous experimental findings indicate that the orientational potential in solid C60 is much stiffer than was anticipated from the nearly spherical shape of the C 60 molecule and the rather large intermolecular distance — a fact, which remains to be properly understood. In this review we summarize experimental studies which allow one to extract information on the orientational potential. The experimental results are contrasted with predictions from various empirical potentials proposed in the literature. Special emphasis is laid on X-ray and neutron diffuse scattering results and how these results can be exploited to further our knowledge on the orientational potential.
Dielectric and Rheological Behaviors of Semiconductive Polymer Suspension as an Electrorheological Fluid
Authors: Chin B. D. , Park O. O. , Lee Y. S.
Published: July 2002

We have studied the dielectric and rheological characteristics of semiconductive polymer based ER fluids. Under static electric field, yield stress of suspension was found to be closely related to the dielectric properties that is in accord with the Maxwell–Wagner interfacial polarization. The dielectric constant showed maximum then decreased with increasing bulk conductivity of particle as the yield stress behaviors did. Particle-medium interaction on ER response was also examined by utilizing appropriate surfactant. These experimental results were consistent with the prediction based on the recent model studies. Over wide range of temperature, our ER fluid maintains its activity so that it can broaden the potential applicability as a smart material.
A NOVEL SUPERCONDUCTING GLASS STATE IN DISORDERED THIN FILMS IN CLOGSTON LIMIT
Authors: ZHOU FEI
Published: July 2002

A theory of mesoscopic fluctuations in disordered thin superconducting films in a parallel magnetic field is developed. At zero temperature and at a sufficiently strong magnetic field, the superconducting state undergoes a phase transition into a state characterized by superfluid densities of random signs, instead of a spin polarized disordered Fermi liquid phase. Consequently, in this regime, random supercurrents are spontaneously created in the ground state of the system, which belongs to the same universality class as the two dimensional XY spin glass. As the magnetic field increases further, mesoscopic pairing states are nucleated in an otherwise homogeneous spin polarized disordered Fermi liquid. The statistics of these pairing states is universal depending on the sheet conductance of the two-dimensional film.
Frustration Effects in the Two-Dimensional Hubbard Model
Authors: LIN HAI QING , LI JUN
Published: July 2002

We discuss frustration effects by studying the two-dimensional Hubbard model with nearest-neighbor(t) and next-nearest-neighbor(t′) hoppings. We present results obtained by the mean-field solution, the exact diagonalization technique, and the quantum Monte Carlo simulations. Questions to be addressed are: (1) magnetic phase diagram; (2) domain formation; and (3) superconducting pair correlation functions.
CHANGES IN SUPERCONDUCTING GAP ANISOTROPY WITH DOPING AND IMPLICATIONS FOR THE PENETRATION DEPTH
Authors: MESOT J. , NORMAN M. R. , FRETWELL H. M. , KAMINSKI A. , CAMPUZANO J. C. , DING H. , RANDERIA M. , PARAMEKANTI A. , TAKEUCHI T. , MOCHIKU T. , YOKOYA T. , SATO T. , TAKAHASHI T. , KADOWAKI K.
Published: July 2002

The momentum dependence of the superconducting gap at low temperatures is precisely determined from angle resolved photoemission (ARPES) measurements on overdoped and underdoped samples of Bi2212. As the doping decreases, the maximum gap increases, but the slope of the gap near the nodes decreases. Though consistent with d-wave symmetry, the gap with underdoping cannot be fit by the simple cos (kx)- cos (ky) form. We suggest that this arises due to the increasing importance of long range interactions as one approaches the insulator. Furthermore, a comparison of our ARPES results with available penetration depth data clearly indicates that the renormalization of the linear T suppression of the superfluid density at low temperatures due to quasiparticle excitations around the d-wave nodes is large and doping dependent.
ON THE OUT-OF-PLANE MAGNETOTRANSPORT IN YBa2Cu3Oy
Authors: FUJITA SHIGEJI , TAMURA YOSHIYASU , SUZUKI AKIRA
Published: July 2002

The out-of-plane resistivity, ρc, in a single-crystal YBa 2 Cu 3 O y follows the experimental law: ρc=C1ρab+C2/T, where C1, C2 are the constants and ρab is in-plane resistivity in the concentration range 6.6<y<6.92 with the highest T c , 90 K, occurring at y=6.88 and in the temperature range T c <T< room temperature. This behavior is microscopically explained under the assumption that the charge carriers are a mixture of "electrons", "holes", and ±pairons. The second term C2/T arises from the quantum tunneling between copper planes of the – pairons, moving with a linear dispersion relation, and the first term C1ρab from the in-plane currents due to the "holes" and +pairons.
LOW TEMPERATURE PROPERTIES OF THE MOTT–HUBBARD TRANSITION
Authors: TONG NING-HUA , SHEN SHUN-QING
Published: July 2002

The unanalytical feature of the Mott–Hubbard metal-insulator transition in infinite dimensions is studied by using a modified self-consistency scheme in the framework of dynamical mean-field theory. For a specific low temperature T=0.0025W (W: half bandwidth), the "Z"-shaped or "S"-shaped curves for double occupancy D, energy per lattice site E, and the quasi-particle weight Z are obtained as functions of U. Direct observation shows that the Fermi-liquid phase changes to the insulating phase through a non-Fermi-liquid phase at the unstable level. Based on our results, a scenario of zero temperature MIT is proposed. The phase diagram for MIT on the T–D plane is also presented.
MINIMUM UNCERTAINTY RELATION OBEYED BY SWH PHASE OPERATOR IN TWO-MODE COHERENT STATE
Authors: HONGYI FAN , ZHIHU SUN
Published: July 2002

We study the minimum uncertainty relation obeyed by the phase operator [Formula: see text] in two-mode coherent state. The operator is suitable for Shapiro–Wagner heterodyne phase measurement scheme. It is due to the |ξ> representation (see Eq. (4)) that the difficulty brought by nonlinear square root operation in [Formula: see text] can be avoided in calculating miscellaneous expectation values. Just as the single-mode coherent state | z1> makes uncertainty relation, satisfied by S–G phase operator, minimum for large |z1|2, we show that |z1,z2> makes uncertainty relation obeyed by [Formula: see text] minimum when |z1|=|z2| is large enough. Some figures are plotted to support our conclusion.
DECOMPOSITION OF PARTIALLY OCCLUDED STRINGS IN THE PRESENCE OF ERRORS
Authors: ILIOPOULOS COSTAS S. , REID JAMES F.
Published: July 2002

A partially occluded scene in an image consists of a number of objects that are partially obstructed by others. By validating a partially occluded image one aims to generate a sequence of concatenated and possibly overlapping objects that corresponds to the input image.

This is a theoretical study of partially occluded strings (considered as one-dimensional images) allowing for the presence of errors in each occluded object appearing in the input. Using the unit cost edit distance as our measure of errors, for some small integer k ≥ 0, we present a sequential algorithm for validating a k-approximate one-dimensional image x of length n over a dictionary [Formula: see text] of m objects each having equal length τ in O(nd) time where d = mτ is the size of the dictionary.
A HYBRID STOCHASTIC-CONNECTIONIST APPROACH TO GESTURE RECOGNITION
Authors: CORRADINI ANDREA , BOEHME HANS-JOACHIM , GROSS HORST-MICHAEL
Published: July 2002

In this paper a person-specific saliency system and subsequently two architectures for the recognition of dynamic gestures are described. The systems implemented are designed to take a sequence of images and to assign it to one of a number of discrete classes where each of them corresponds to a gesture from a predefined small vocabulary. Since we think that for a human-computer interaction the localization of the user is essential for any further step regarding the recognition and the interpretation of gestures, in the first part, we begin with describing our saliency system dedicated to the person localization task in cluttered environments. Successively, the intrinsic gesture recognition process is broken down into an initial preprocessing stage followed by a mapping from the preprocessed input variables to an output variable representing the class label. Subsequently, we utilize two different classifiers for mapping the ordered sequence of feature vectors to one gesture category. The first classifier utilizes a hybrid combination of Kohonen Self-Organizing Map (SOM) and Discrete Hidden Markov Models (DHMM). As second recognizer a system of Continuous Hidden Markov Models (CHMM) is used. Preliminary experiments with our baseline systems are demonstrated.
EFFICIENT DEFEASIBLE REASONING SYSTEMS
Authors: MAHER MICHAEL J. , ROCK ANDREW , ANTONIOU GRIGORIS , BILLINGTON DAVID , MILLER TRISTAN
Published: July 2002

For many years, the non-montonic reasoning community has focussed on highly expressive logics. Such logics have turned out to be computationally expensive, and have given little support to the practical use of non-monotonic reasoning. In this work we discuss defeasible logic, a less-expressive but more efficient non-monotonic logic. We report on two new implemented systems for defeasible logic: a query answering system employing a backward-chaining approach, and a forward-chaining implementation that computes all conclusions. Our experimental evaluation demonstrates that the systems can deal with large theories (up to hundreds of thousands of rules). We show that defeasible logic has linear complexity, which contrasts markedly with most other non-monotonic logics and helps to explain the impressive experimental results. We believe that defeasible logic, with its efficiency and simplicity, is a good candidate to be used as a modeling language for practical applications, including modelling of regulations and business rules.
A COMPUTATION OF SUPERBRIDGE INDEX OF KNOTS
Authors: JEON CHOON BAE , JIN GYO TAEK
Published: July 2002

We show that the list {31, 41, 52, 61, 62, 63, 72, 73, 74, 84, 87, 89} contains all 3-superbridge knots. We also supply the best known estimates of the superbridge index for all prime knots up to nine crossings.
FAIR DIVISION UNDER INTERVAL UNCERTAINTY
Authors: YAGER RONALD R. , KREINOVICH VLADIK
Published: July 2002

It is often necessary to divide a certain amount of money between n participants, i.e., to assign, to each participant, a certain portionwi≥0 of the whole sum (so that w1+⋯+ wn=1). In some situations, from the fairness requirements, we can uniquely determine these "weights" wi. However, in some other situations, general considerations do not allow us to uniquely determine these weights, we only know the intervals[Formula: see text] of possible fair weights. We show that natural fairness requirements enable us to choose unique weights from these intervals; as a result, we present an algorithm for fair division under interval uncertainty.
RISK ANALYSIS OF A ROBOT-SAFETY DEVICE SYSTEM
Authors: VANDERPERRE E. J. , MAKHANOV S. S.
Published: July 2002

We consider the robot-safety device system as described in: Vanderperre and Makhanov, International Journal of Reliability, Quality and Safety Engineering 7 (2000) 169–175. The engineering system is characterized by the natural feature of cold standby and by a possible risky state. Apart from some tangible results obtained in the previous Literature, we introduce a risk function associated with the risky state of the robot. The risk function is determined by a coupled pair of convolution-type integral equations. In order to decide whether the risky state is admissible or reprehensible, we also introduce a suitable risk-criterion involving the supremum norm. We demonstrate that the criterion is always satisfied in the particular but important case of "fast" repair. Finally, we propose a numerical procedure to solve the system of integral equations and we calculate the underlying risk function.
TRANSSTYLOID RADIOCARPAL DISLOCATION
Authors: Watanabe Kentaro , Nishikimi Junzo
Published: July 2002

We presented two cases of a transstyloid radiocarpal dislocation which required operative treatment and resulted in satisfactory outcomes. This lesion has been liable to confuse with some types of intra-articular fractures of the distal radius such as Barton's fracture. Previous reports were also critically reviewed.
Carpal Tunnel Syndrome; Its Natural History
Authors: Futami Toshiro , Kobayashi Akimasa , Ukita Toyohiko , Endoh Tachio , Fujita Tadashi
Published: July 2002

Two hundred and fifty-seven carpal tunnel syndrome patients without specific treatments were followed up for more than 5 years. Several background factors of these patients, such as possible causes, ages, sex, and involved site were surveyed in order to determine whether these factors might affect the end-results or not. The overall results showed that approximately 1/3 of untreated CTS patients were completely free from any clinical symptoms within 6 months on average. Positive correlations were found in causes, ages and sex. Younger female patients in their pregnancy had the highest remission rate; however, active middle-aged male patients had the lowest remission rate. No correlation was found between the end-results and the electrophysiological nerve conduction studies, taken at their first visits.
Bilateral Double Extensor Pollicis Longus Tendons: Segmentation or Coalition?
Authors: Chamberlain S. T. , Burke F. D.
Published: July 2002

A case of bilateral double extensor pollicis longus tendons is described in a patient with rheumatoid arthritis undergoing extensor teno-synovectomy. The authors believe this to be a rare anomaly and would like to use this anatomical finding as an opportunity to increase our understanding of thumb development and specialization.
SPIN GLASSES IN THE TRADING BOOK
Authors: KONDOR I.
Published: July 2002

The standard model defined in the Capital Adequacy Directive issued by the EEC in 1993 imposes nonlinear constraints on certain parts of the trading portfolios of financial institutions. It is shown that an institution that complies with the rules of the standard model but wants to optimize its portfolio according to some internal criteria, such as minimizing the variance or the VaR, faces a computational problem equivalent to finding the ground states of a long range spin glass. This problem is known to be NP-complete, and to have exponentially many solutions which are extremely sensitive to any changes of the input parameters.
AN ORDINAL ANALYSIS OF ADMISSIBLE SET THEORY USING RECURSION ON ORDINAL NOTATIONS
Authors: AVIGAD JEREMY
Published: July 2002

The notion of a function from ℕ to ℕ defined by recursion on ordinal notations is fundamental in proof theory. Here this notion is generalized to functions on the universe of sets, using notations for well orderings longer than the class of ordinals. The generalization is used to bound the rate of growth of any function on the universe of sets that is Σ1-definable in Kripke–Platek admissible set theory with an axiom of infinity. Formalizing the argument provides an ordinal analysis.
LINEAR BOUNDS AND GAUSSIAN TAILS IN A STOCHASTIC DISPERSION MODEL
Authors: LISEI HANNELORE , SCHEUTZOW MICHAEL
Published: July 2002

Recently, Cranston, Scheutzow and Steinsaltz showed that the image at time T of a bounded set [Formula: see text] under the action of a stochastic flow on Rd with Lipschitz and bounded characteristics is almost surely contained in a ball of radius KT around the origin for all sufficiently large T. Here K is a constant which depends on the dimension d and the characteristics of the flow (but not on the set [Formula: see text]). We improve these results in three different ways: our proof is shorter and more transparent, the bound K which we obtain is sharper and we are able to improve the bounds on the tails of the distance of the most distant point in the image at time T to be genuinely sub-Gaussian.
SUCCESS AND SUSTAINABILITY IN AUTOMOTIVE SUPPLY CHAIN IMPROVEMENT PROGRAMMES: A CASE STUDY OF COLLABORATION IN THE MAYFLOWER CLUSTER
Authors: TILSON BARBARA
Published: July 2002

The case study of the Mayflower Vehicle Systems PLC supply chain improvement programme offers a window onto a change programme implemented by one supply chain cluster of the UK automotive industry. The discussion details the transformational nature of change agent empowerment, stakeholder engagement, team-working and the dynamics of intra-firm and customer-supplier collaboration between a first tier company and its sub-suppliers. It shows that improvement programmes have a crucial function in helping customer and suppliers to closer collaboration through enabling them to work towards common objectives, to understand each other's positions, and to build on a platform of mutual trust as they strive to improve their individual and collective competitiveness and establish mechanisms to ensure that improvements are sustainable. The study has further value in illuminating the adaptation of a lean production model akin to the Toyota Production System to a specific case supported by the Accelerate Initiative and facilitated by the Society of Motor Manufacturers and Traders' Industry Forum.
A multimodel methodology for qualitative model engineering
Authors: Fishwick Paul A. , Zeigler Bernard P.
Published: July 2002

Qualitative models arising in artificial intelligence domain often concern real systems that are difficult to represent with traditional means. However, some promise for dealing with such systems is offered by research in simulation methodology. Such research produces models that combine both continuous and discrete-event formalisms. Nevertheless, the aims and approaches of the AI and the simulation communities remain rather mutually ill understood. Consequently, there is a need to bridge theory and methodology in order to have a uniform language when either analyzing or reasoning about physical systems. This article introduces a methodology and formalism for developing multiple, cooperative models of physical systems of the type studied in qualitative physics. The formalism combines discrete-event and continuous models and offers an approach to building intelligent machines capable of physical modeling and reasoning.
The membership problem in aperiodic transformation monoids
Authors: Beaudry M. , McKenzie P. , Thérien D.
Published: July 2002

The problem of testing membership in aperiodic or “group-free” transformation monoids is the natural counterpart to the well-studied membership problem in permutation groups. The class
A
of all finite aperiodic monoids and the class
G
of all finite groups are two examples of
varieties
, the fundamental complexity units in terms of which finite monoids are classified. The collection of all varieties
V
forms an infinite lattice under the inclusion ordering, with the subfamily of varieties that are contained in
A
forming an infinite sublattice. For each
V
⊆
A
, the associated problem MEMB(
V
) of testing membership in transformation monoids that belong to
V
, is considered. Remarkably, the computational complexity of each such problem turns out to look familiar. Moreover, only five possibilities occur as
V
ranges over the whole aperiodic sublattice: With one family of NP-hard exceptions whose exact status is still unresolved, any such MEMB(
V
) is either PSPACE-complete, NP-complete, P-complete or in AC
0
. These results thus uncover yet another surprisingly tight link between the theory of monoids and computational complexity theory.
CYC, WordNet, and EDR
Authors: Lenat Doug , Miller George , Yokoi Toshio
Published: July 2002

I applaud Miller's WordNet project and feel that there is much in common in our approaches, even though there are fundamental differences in the two expressions of that spirit. Here, I list the four differences I noted, closing with a crucial observation concerning the common spirit in our work.
Robust wait-free hierarchies
Authors: Jayanti Prasad
Published: July 2002

The problem of implementing a shared object of one type from shared objects of other types has been extensively researched. Recent focus has mostly been onwait-free implementations, which permit every process to complete its operations on implemented objects, regardless of the speeds of other processes. It is known that shared objects of different types have differing abilities to support wait-free implementations. It is therefore natural to want to arrange types in a hierarchy that reflects their relative abilities to support wait-free implementations. In this paper, we formally define robustness and other desirable properties of hierarchies. Roughly speaking, a hierarchy is robust if each type is “stronger” than any combination of lower level types. We study two specific hierarchies: one, that we callhrmin which the level of a type is based on the ability of anunboundednumber of objects of that type, and another hierarchy, that we callhr1, in which a type's level is based on the ability of afixednumber of objects of that type. We prove that resource bounded hierarchies, such ashr1and its variants, are not robust. We also establish the unique importance ofhrm: every nontrivial robust hierarchy, if one exists, is necessarily a “coarsening” ofhrm.
Software reliability via run-time result-checking
Authors: Wasserman Hal , Blum Manuel
Published: July 2002

We review the field of result-checking, discussing simple checkers and self-correctors. We argue that such checkers could profitably be incorporated in software as an aid to efficient debugging and enhanced reliability. We consider how to modify traditional checking methodologies to make them more appropriate for use in real-time, real-number computer systems. In particular, we suggest that checkers should be allowed to use stored randomness: that is, that they should be allowed to generate, preprocess, and store random bits prior to run-time, and then to use this information repeatedly in a series of run-time checks. In a case study of checking a general real-number linear transformation (e.g., a Fourier Transform), we present a simple checker which uses stored randomness, and a self-corrector which is particularly efficient if stored randomness is employed.
Temporal FDs on complex objects
Authors: Wijsen Jef
Published: July 2002

Temporal functional dependencies
(TFD) are defined
for temporal databases that include object identity. It is argued that object identity can overcome certain semantic diffuculties with existing temporal relational data models. Practical applications of TFDs in object bases are discussed. Reasoning about TFDs is at the center of this paper. It turns out that the distinction between acyclic and cyclic schemas is significant. For acyclic schemas, a complete axiomatization for finite implication is given and an algorithm for deciding finite implication provided. The same axiomatization is proven complete for unrestricted implication in unrestricted schemas, which can be cyclic. An interesting result is that there are cyclic schemas for which unrestricted and finite implication do not coincide. TFDs relate and extend some earlier work on dependency theory in temporal databases. Throughout this paper, the construct of TFD is compared with the notion of temporal FD introduced by Wang et al. (1997). A comparison with other related work is provided at the end of the article.
ALPHA—An Automatic Programming System of High Efficiency
Authors: Yershov A. P.
Published: July 2002

An automatic programming system for the M-20 computer at the Computing Centre of the Siberian Division of the USSR Academy of Sciences has been developed. The translator is a compiler which accepts source programs written in ALPHA language (hardware representation of which input language is an extension of ALGOL 60). The language extensions include the ability to handle complex quantities and the ability to consider variables as matrices or vectors. Certain language limitations are imposed concerning recursion and the correspondence between parameters in procedure definitions and calls. The translator itself consists of two phases. The first phase contains 14 blocks and translates a source program to an intermediate language. The second phase which consists of 10 blocks converts the internal language to machine code. The principal objective in designing the compiler was the production of fast, compact object code. Techniques for such achievement are detailed. Since the compiler has been operational for some time, comparative figures are given for a series of programs as compiled by the ALPHA translator and as handwritten by programmers. Further figures compare ALPHA with TA-1 and TA-2 (earlier compilers written for the same computer). A special debugging system operates in conjunction with the ALPHA translator.
Unlinkable serial transactions
Authors: Stubblebine Stuart G. , Syverson Paul F. , Goldschlag David M.
Published: July 2002

We present a protocol for unlinkable serial transactions suitable for a variety of network-based subscription services. It is the first protocol to use cryptographic blinding to enable subscription services. The protocol prevents the service from tracking the behavior of its customers, while protecting the service vendor from abuse due to simultaneous or cloned use by a single subscriber. Our basic protocol structure and recovery protocol are robust against failure in protocol termination. We evaluate the security of the basic protocol and extend the basic protocol to include auditing, which further deters subscription sharing. We describe other applications of unlinkable serial transactions for pay-per-use trans subscription, third-party subscription management, multivendor coupons, proof of group membership, and voting.
A view of the origins and development of Prolog
Authors: Cohen Jacques
Published: July 2002

Dealing with failure is easy: Work hard to improve. Success is also easy to handle: You've solved the wrong problem. Work hard to improve.
Image-driven simplification
Authors: Lindstrom Peter , Turk Greg
Published: July 2002

We introduce the notion of
image-driven simplification
, a framework that uses images to decide which portions of a model to simplify. This is a departure from approaches that make polygonal simplification decisions based on geometry. As with many methods, we use the edge collapse operator to make incremental changes to a model. Unique to our approach, however, is the use at comparisons between images of the original model against those of a simplified model to determine the cost of an ease collapse. We use common graphics rendering hardware to accelerate the creation of the required images. As expected, this method produces models that are close to the original model according to image differences. Perhaps more surprising, however, is that the method yields models that have high geometric fidelity as well. Our approach also solves the quandary of how to weight the geometric distance versus appearance properties such as normals, color, and texture. All of these trade-offs are balanced by the image metric. Benefits of this approach include high fidelity silhouettes, extreme simplification of hidden portions of a model, attention to shading interpolation effects, and simplification that is sensitive to the content of a texture. In order to better preserve the appearance of textured models, we introduce a novel technique for assigning texture coordinates to the new vertices of the mesh. This method is based on a geometric heuristic that can be integrated with any edge collapse algorithm to produce high quality textured surfaces.
The soft heap
Authors: Chazelle Bernard
Published: July 2002

A simple variant of a priority queue, called a
soft heap
, is introduced. The data structure supports the usual operations: insert, delete, meld, and findmin. Its novelty is to beat the logarithmic bound on the complexity of a heap in a comparison-based model. To break this information-theoretic barrier, the entropy of the data structure is reduced by artifically raising the values of certain keys. Given any mixed sequence of
n
operations, a soft heap with error rate ε (for any 0 < ε ≤ 1/2) ensures that, at any time, at most
εn
of its items have their keys raised. The amortized complexity of each operation is constant, except for insert, which takes
0
(log 1/ε)time. The soft heap is optimal for any value of ε in a comparison-based model. The data structure is purely pointer-based. No arrays are move items across the data structure not individually, as is customary, but in groups, in a data-structuring equivalent of “car pooling.” Keys must be raised as a result, in order to preserve the heap ordering of the data structure. The soft heap can be used to compute exact or approximate medians and percentiles optimally. It is also useful for approximate sorting and for computing minimum spanning trees of general graphs.
A recurrence scheme for converting from one orthogonal expansion into another
Authors: Salzer Herbert E.
Published: July 2002

A generalization of a scheme of Hamming for converting a polynomial P
n
(x) into a Chebyshev series is combined with a recurrence scheme of Clenshaw for summing any finite series whose terms satisfy a three-term recurrence formula. An application to any two orthogonal expansions P

n

(
x
) = ∑

n

m
=0

a
m
q
m

(
x
) = ∑

n

m
=0

A
m
Q
m

(
x
) enables one to obtain

A
m

directly from

a
m

,
m
= 0(1)
n
, by a five-term recurrence scheme.