bluuebunny/crossref_metadata_2025 huggingface dataset:
Crustal motion along the Eurasia‐Nubia plate boundary in the Calabrian Arc and Sicily and active extension in the Messina Straits from GPS measurements
Authors: D’Agostino Nicola , Selvaggi Giulio
Published: November 2004

We investigate crustal deformation along the Eurasia‐Nubia plate boundary in Calabria and Sicily revealed by the GPS velocity field obtained by the combination of continuous site velocities with previous results from episodic campaigns. We recognize two distinct crustal domains characterized by different motions and styles of deformation. Convergence in Sicily is taken up by crustal shortening along the former Tyrrhenian back arc passive margin, in agreement with seismological data and geological evidence of recent cessation of deformation along the Plio‐Pleistocene subduction front. The analysis of the GPS data and the consistency between earthquake slip vectors and convergence direction suggest that Eu‐Nu convergence in Sicily does not require intermediate crustal blocks. Significant Eurasia (∼3 mm/yr to NNE) and Nubia‐fixed (∼5 mm/yr to ESE) residual velocities in Calabria suggest instead the presence of an intermediate crustal block which can be interpreted as a forearc sliver or as an independent Ionian block. According to the first hypothesis, subduction is still active in the Ionian wedge, although we find no evidence for active back arc spreading in the Tyrrhenian Sea. The N115°E oriented Sicily‐Calabria GPS relative motion is consistent with the extension observed during the 1908 Mw 7.1 Messina earthquake. We suggest that up to 3 mm/yr (∼80%) of this estimated relative motion between Sicily and the Calabrian Arc may be taken up in the Messina Straits.
Laminar drag reduction in microchannels using ultrahydrophobic surfaces
Authors: Ou Jia , Perot Blair , Rothstein Jonathan P.
Published: November 2004

A series of experiments is presented which demonstrate significant drag reduction for the laminar flow of water through microchannels using hydrophobic surfaces with well-defined micron-sized surface roughness. These ultrahydrophobic surfaces are fabricated from silicon wafers using photolithography and are designed to incorporate precise patterns of microposts and microridges which are made hydrophobic through a chemical reaction with an organosilane. An experimental flow cell is used to measure the pressure drop as a function of the flow rate for a series of microchannel geometries and ultrahydrophobic surface designs. Pressure drop reductions up to 40% and apparent slip lengths larger than 20 μm are obtained using ultrahydrophobic surfaces. No drag reduction is observed for smooth hydrophobic surfaces. A confocal surface metrology system was used to measure the deflection of an air–water interface that is formed between microposts and supported by surface tension. This shear-free interface reduces the flow resistance by allowing the fluid to contact only a very small effective area of the silicon surface. The impact of the surface topology on the drag reduction is explored in detail and the results are found to be in good qualitative agreement with the predictions of analytical theory.
High-power-density fault-current limiting devices using superconducting YBa2Cu3O7 films and high-resistivity alloy shunt layers
Authors: Yamasaki Hirofumi , Furuse Mitsuho , Nakagawa Yoshihiko
Published: November 2004

Switching of superconducting thin-film resistive fault-current limiting devices with alloy shunt layers was studied. Au–Ag alloy thin films, whose room-temperature resistivity is about six times higher than that of pure gold, were sputter deposited on YBa2Cu3O7 films on sapphire substrates with high critical current density of Jc=3.05±0.05MA∕cm2. A small sample, 5mm wide and 40mm long, had the capacity of a rated current of 32Arms in normal operation and withstood a high voltage of 107Vrms for 0.1s after switching, resulting in a very high switching power density of ∼1.7kVA∕cm2, which is more than four times higher than conventional devices using gold shunt layers.
Exchange-diffusion reactions in HfSiON during annealing studied by Rutherford backscattering spectrometry, nuclear reaction analysis and narrow resonant nuclear reaction profiling
Authors: Miotti L. , Bastos K. P. , Soares G. V. , Driemeier C. , Pezzi R. P. , Morais J. , Baumvol I. J. R. , Rotondaro A. L. P. , Visokay M. R. , Chambers J. J. , Quevedo-Lopez M. , Colombo L.
Published: November 2004

HfSiON films deposited on Si (001) by reactive sputtering were submitted to rapid thermal annealing at 1000°C in vacuum, N2 and O2 atmospheres. The stability of the dielectric was evaluated by measuring the atomic transport and exchange of the chemical species, using Rutherford backscattering spectrometry, nuclear reaction analysis and narrow resonant nuclear reaction profiling. Annealing in O2 ambient reduced the N concentration mainly from near-surface regions where oxygen was incorporated in comparable amounts. Vacuum annealing, on the other hand, induced N loss preferentially from the Si/dielectric interface and O loss preferentially from near-surface regions. The results are explained in terms of exchange-diffusion reactions occurring in the HfSiON.
Growth, optical characterization, and laser operation of epitaxial Yb:KY(WO4)2∕KY(WO4)2 composites with monoclinic structure
Authors: Aznar A. , Solé R. , Aguiló M. , Diaz F. , Griebner U. , Grunwald R. , Petrov V.
Published: November 2004

Epitaxial monoclinic double tungstate laser crystals were grown with high crystalline quality. Based on these Yb-doped composites, laser operation was demonstrated. Continuous-wave laser emission of a Yb:KYW∕KYW crystal was achieved at 1030nm. The 25-μm-thin Yb:KYW layer was pumped at wavelengths near 980nm by a Ti:sapphire laser. A maximum output power of 40mW was obtained at room temperature.
Influence of the surface termination to the point imaging by a photonic crystal slab with negative refraction
Authors: Xiao Sanshui , Qiu Min , Ruan Zhichao , He Sailing
Published: November 2004

Point imaging by a photonic crystal slab due to the negative refraction is studied theoretically. By investigating the transfer function of the imaging system, the influence of the surface termination to the imaging quality is analyzed. It is shown that an appropriate surface termination is important for obtaining an image of good quality.
Five-day-long ferroelectric memory effect in Pt∕(Bi,La)4Ti3O12∕HfO2∕Si structures
Authors: Park Byung-Eun , Takahashi Kazuhiro , Ishiwara Hiroshi
Published: November 2004

In order to form metal–ferroelectric–semiconductor–insulator–semiconductor (MFIS) structures, hafnium oxide (HfO2) films were first deposited on Si(100) substrates at room temperature using an electron-beam evaporation method. Then, they were annealed in an O2 atmosphere at 800°C for 1min. No hysteretic characteristics were observed in the capacitance–voltage (C–V) measurement for the metal–insulator–semiconductor capacitors. On these films, lanthanum-substituted bismuth titanate [(Bi,La)4Ti3O12:BLT] films with 380nm in thickness were deposited by a sol–gel spin-coating method and annealed in an O2 atmosphere at 750°C for 30min. The MFIS sample showed the hysteretic C–V characteristics and the memory window width was about 0.9V for the voltage sweep of ±7V. Furthermore, the high and low capacitance values biased in the hysteresis loop were clearly distinguishable for over 5 days. The origin of the excellent data retention characteristics is discussed from a viewpoint of the transient current across the film.
One-dimensional heterostructural metallodielectric photonic band gap material for the modification of emission spectrum of BaF2 scintillator
Authors: Wu Yonggang , Wang Zhanshan , Gu Mu , Wang Li , Lin Xiaoyan , Chen Lingyan , Xu Rongkun
Published: November 2004

One-dimensional metallodielectric heterostructural photonic band gap (PBG) material is designed to reach high transmittance band in short wavelength, broad and deep forbidden band in long wavelength, especially sharp cutoff edge between the transmission and forbidden bands. The designed PBG material is applied to modify the emission spectrum of a BaF2 scintillator and is proved to be adequate to suppress the slow component of the scintillation light. The suppression ratio of the slow to the fast component reaches 28dB with a tolerable attenuation of the fast component.
Self-assembled infrared-luminescent Er–Si–O crystallites on silicon
Authors: Isshiki H. , de Dood M. J. A. , Polman A. , Kimura T.
Published: November 2004

Optically active and electrically excitable erbium complexes on silicon are made by wet-chemical synthesis. The single-crystalline Er–Si–O compound is formed by coating a Si(100) substrate with an ErCl3∕ethanol solution, followed by rapid thermal oxidation and annealing. Room-temperature Er-related 1.53μm photoluminescence is observed with a peak linewidth as small as 4meV. The complexes can be excited directly into the Er intra-4f states, or indirectly, through photocarriers. Er concentrations as high as 14at.% are achieved, incorporated in a crystalline lattice with a 0.9nm periodicity. Thermal quenching at room temperature is only a factor 5, and the lifetime at 1.535μm is 200μs.
Influence of the dielectric roughness on the performance of pentacene transistors
Authors: Steudel Soeren , De Vusser Stijn , De Jonge Stijn , Janssen Dimitri , Verlaak Stijn , Genoe Jan , Heremans Paul
Published: November 2004

The properties of the dielectric strongly influence the performance of organic thin-film transistors. In this letter, we show experimental results that quantify the influence of the roughness of the dielectric on the mobility of pentacene transistors and discuss the cause of it. We consider the movement of charge carriers out of the “roughness valleys” or across those valleys at the dielectric–semiconductor interface as the limiting step for the roughness-dependent mobility in the transistor channel.
Fabrication of high-efficiency Fresnel-type lenses by pinhole diffraction imaging of sol-gel hybrid materials
Authors: Kang Dong Jun , Phong Phan Viet , Bae Byeong-Soo
Published: November 2004

Sol-gel hybrid materials containing a large quantity of photoactive molecules exhibited large changes in both refractive index and volume on UV exposure. The materials were used for fabrication of Fresnel-type lenses using a simple method: pinhole diffraction imaging. With this technique, problems associated with the contact method could be overcome and Fresnel-type lenses with good focusing performance could be fabricated easily. Importantly, a high diffraction efficiency approaching 85% could be obtained.
Greenish-white electroluminescence from p-type CuGaS2 heterojunction diodes using n-type ZnO as an electron injector
Authors: Chichibu S. F. , Ohmori T. , Shibata N. , Koyama T. , Onuma T.
Published: November 2004

Greenish-white electroluminescence (EL) was observed from p-type (001) CuGaS2 chalcopyrite semiconductor epilayers grown on a (001) GaP substrate by metalorganic vapor phase epitaxy, due to the electron injection from preferentially (0001)-oriented polycrystalline n-type ZnO thin films deposited by the surface-damage-free helicon-wave-excited-plasma sputtering method. The structure was designed to enable the electron injection from n-type wide band gap partner forp-CuGaS2 forming the ZnO∕CuGaS2 TYPE-I heterojunction. The EL spectra exhibited emission peaks and bands between 1.6 and 2.5eV, although the higher energy portion was absorbed by the GaP substrate. Since the spectral line shape resembled that of the photoluminescence from the identical CuGaS2 epilayers, the EL was assigned to originate from p-CuGaS2.
Acoustic radiation pressure: A “phase contrast” agent for x-ray phase contrast imaging
Authors: Bailat Claude J. , Hamilton Theron J. , Rose-Petruck Christoph , Diebold Gerald J.
Published: November 2004

We show that the radiation pressure exerted by a beam of ultrasound can be used for contrast enhancement in high-resolution x-ray imaging of tissue and soft materials. Interfacial features of objects are highlighted as a result of both the displacement introduced by the ultrasound and the inherent sensitivity of x-ray phase contrast imaging to density variations. The potential of the method is demonstrated by imaging microscopic tumor phantoms embedded into tissue with a thickness typically presented in mammography. The detection limit of micrometer size masses exceeds the resolution of currently available mammography imaging systems. The directionality of the acoustic radiation force and its localization in space permits the imaging of ultrasound-selected tissue volumes. The results presented here suggest that the method may permit the detection of tumors in soft tissue in their early stage of development.
High tunability barium strontium titanate thin films for rf circuit applications
Authors: Pervez N. K. , Hansen P. J. , York R. A.
Published: November 2004

Large variations in the permittivity of rf magnetron sputtered thin-film barium strontium titanate have been obtained through optimization of growth conditions for maximum dielectric strength and zero-field permittivity in a parallel-plate capacitor structure. Using nominal target compositions of Ba0.5Sr0.5TiO3, and Pt electrodes on c-plane sapphire substrates, adjustment of the O2 partial pressure during deposition was used to vary the excess Ti incorporation into the films, which influenced the low-field permittivity, loss tangent, and dielectric strength. By balancing the benefits of a high permittivity with dielectric strength and loss, we have produced films capable of sustaining short-duration fields greater than 4MV∕cm with over 13:1 (>90%) change in dielectric constant, and greater than 5:1 tunability in bias fields under 1MV∕cm.
Quasicrystal formation in mechanically alloyed Zr–Ti–Nb–Cu–Ni–Al glassy powders
Authors: Scudino S. , Mickel C. , Schultz L. , Eckert J. , Yang X. Y. , Sordelet D. J.
Published: November 2004

Different from the glassy Zr62Ti7.07Nb2.21Cu12.28Ni9.81Al6.62 melt-spun ribbon that forms a quasicrystalline phase upon devitrification, the corresponding alloy produced by mechanical alloying of elemental powder mixtures does not clearly show quasicrystal formation. However, the addition of an appropriate amount of elemental zirconium to the mechanically alloyed powder changes the crystallization behavior inducing the formation of an icosahedral quasicrystalline phase as the first crystallization product. This indicates that for this multicomponent metallic glass quasicrystal formation in the mechanically alloyed powder is crucially linked to the composition rather than to the question whether there is a special quenched-in short-range order.
Electronic structure and charge distribution of potassium iodide intercalated single-walled carbon nanotubes
Authors: Yam ChiYung , Ma ChiChiu , Wang XiuJun , Chen GuanHua
Published: November 2004

Recently, potassium iodide was inserted into single-walled carbon nanotubes. We present here a first-principles density-functional theory calculation of the electronic and optical properties of a potassium iodide intercalated (10,10) nanotube. Band structure, density of states, and charge distribution of the intercalated nanotube are determined. Significant changes in the electronic structure of carbon nanotube are found upon the intercalation. In particular, the electron distribution on the tube becomes more diffusive, and one out of every four K4s electrons transfers to the tube wall, while the other three go to I5p orbitals.
Single-cell detection by cavity ring-down spectroscopy
Authors: Tarsa Peter B. , Wist Aislyn D. , Rabinowitz Paul , Lehmann Kevin K.
Published: November 2004

The implementation of cavity ring-down spectroscopy in an optical fiber resonator extends the viability of this highly sensitive technique for label-free detection of biological species. By chemically treating the surface of discrete tapered sensing regions along the length of a physically extended optical fiber resonator, we show single-cell sensitivity arising from optical scattering of the evanescent field surrounding the fiber. The observed detection limits, based on a minimum detectable scattering cross section on the order of 10μm2, suggest a broad range of new applications in a simple, inexpensive device for real-time cavity ring-down biosensing.
Phylogeny, taxonomy and biology of mites of the genera Chelacheles and Neochelacheles (Acari : Cheyletidae)
Authors: Bochkov Andre V. , OConnor Barry M.
Published: November 2004

Taxonomic revision and parsimony-based phylogenetic analysis of species in two closely related genera of predaceous Cheyletidae, Chelacheles Baker and Neochelacheles Smiley & Williams, are conducted. Among species of these genera, C. algericus Fain & Bochkov, syn. nov. and C. humilis Rasool, Chaudhri & Akbar, syn. nov. are synonymised with C. strabismus Baker and C. bakeri Attiah, respectively. Six new species are described: C.�aigamuxa, sp. nov.; C. klimovi, sp. nov.; C. seminole, sp. nov.; C. temoak, sp. nov.; N. corpuzrarosae, sp. nov.; and N. mendicus, sp. nov. The genus Chelacheles includes two species-groups, strabismus (seven species) and peritremaculatus (seven species), and two ungrouped species, C. michalskii Samsinak and C. stigmaeoides Barilo. The genus Neochelacheles (three species) is represented by a single species from North America and by two Philippine endemics. New diagnoses of the genera are given as well as descriptions of postembryonic stages of a model species in each genus, a key, and redescriptions for most species. The biology of these mites is briefly discussed. Phylogenetic analysis indicates that the associations of some species with polypore bracket fungi have arisen independently in the genera Chelacheles and Neochelacheles.
Residual Stress Measurement on Fibre-metal-laminates
Authors: Hofslagare Per
Published: November 2004

A comparison between different residual stress measurement methods on fibre reinforced metal laminates was made. The methods used were X-ray diffraction, neutron diffraction and strain measurement throughout destructively produced stress release. Good agreement was found between the different methods. For these types of laminates, thermally caused residual stresses arise during manufacture. Stretch operation of the laminate will modify the residual stress state. It is well documented that the residual stress state greatly affects the fatigue properties of these laminates, not only during the fatigue initiation stage but also during fatigue crack propagation [1–3]. Neutron diffraction residual stress measurements have also been performed on fatigue-damaged material, specifically in the wake of a fatigue-induced metal crack in the laminate. Delamination and fibre degeneration occur to some extent in the surroundings of the fatigue-induced metal flaw. This will cause a relaxation of the compressive residual stress, and it will affect further development of the fatigue damage.
The two cytochrome c species, DC3 and DC4, are not required for caspase activation and apoptosis in Drosophila cells
Authors: Dorstyn Loretta , Mills Kathryn , Lazebnik Yuri , Kumar Sharad
Published: November 2004

In Drosophila, activation of the apical caspase DRONC requires the apoptotic protease-activating factor homologue, DARK. However, unlike caspase activation in mammals, DRONC activation is not accompanied by the release of cytochrome c from mitochondria. Drosophila encodes two cytochrome c proteins, Cytc-p (DC4) the predominantly expressed species, and Cytc-d (DC3), which is implicated in caspase activation during spermatogenesis. Here, we report that silencing expression of either or both DC3 and DC4 had no effect on apoptosis or activation of DRONC and DRICE in Drosophila cells. We find that loss of function mutations in dc3 and dc4, do not affect caspase activation during Drosophila development and that ectopic expression of DC3 or DC4 in Drosophila cells does not induce caspase activation. In cell-free studies, recombinant DC3 or DC4 failed to activate caspases in Drosophila cell lysates, but remarkably induced caspase activation in extracts from human cells. Overall, our results argue that DARK-mediated DRONC activation occurs independently of cytochrome c.
Classification using partial least squares with penalized logistic regression
Authors: Fort Gersende , Lambert-Lacroix Sophie
Published: November 2004

Motivation: One important aspect of data-mining of microarray data is to discover the molecular variation among cancers. In microarray studies, the number n of samples is relatively small compared to the number p of genes per sample (usually in thousands). It is known that standard statistical methods in classification are efficient (i.e. in the present case, yield successful classifiers) particularly when n is (far) larger than p. This naturally calls for the use of a dimension reduction procedure together with the classification one.

Results: In this paper, the question of classification in such a high-dimensional setting is addressed. We view the classification problem as a regression one with few observations and many predictor variables. We propose a new method combining partial least squares (PLS) and Ridge penalized logistic regression. We review the existing methods based on PLS and/or penalized likelihood techniques, outline their interest in some cases and theoretically explain their sometimes poor behavior. Our procedure is compared with these other classifiers. The predictive performance of the resulting classification rule is illustrated on three data sets: Leukemia, Colon and Prostate.

Availability: Software that implements the procedures and data source on which this paper focuses are freely available at http://www-lmc.imag.fr/SMS/membres/Gersende_Fort,Sophie_Lambert.html

Contact:  sophie.lambert@imag.fr
Caravan parks as a provider in the affordable housing market
Authors: Reed Richard , Greenhalgh Emma
Published: November 2004

Caravan parks in Australian capital cities have provided a source of housing at the lower end of the market for many years. This includes opportunities for both private rental and home ownership. However, emerging trends in the property market have threatened the viability of caravan parks. In order to maintain or increase income levels, some caravan parks have focused on more profitable short‐term tourist opportunities rather than traditional long‐term housing. While the closure and conversion of caravan parks raise crucial questions for Australian social and housing policy, there are also implications for the broader property market. This paper examines the changing role of the operation of caravan parks, with the emphasis placed on their economic feasibility. The research is based on a survey of 30 caravan park operators in Queensland, Australia. The factors influencing caravan parks are identified, and suggestions to address the changing role of caravan parks as a provider in the affordable housing market are canvassed.
A cybernetical analysis of entities in multilevel systems
Authors: Lloret‐Climent Miguel , Luis Bonnet‐Jerez Jose
Published: November 2004

Describes issues relevant to multilevel systems and, as a particular case, living systems analysed from the entities point of view. As attributes, behaviours, sub‐systems, etc., entities are primitive terms. For this reason, in examining issues such as the influences between entities, look indirectly at issues referring to different levels in the system. This notion was also extended in considering the environment system and analysing the different relationships between the system and the environment system.
Twenty‐first century – the beginning of human immortality
Authors: Bolonkin Alexander
Published: November 2004

Immortality is the most cherished dream and the biggest wish of any person. People seldom think about it while they are still young, healthy, and full of energy. But when they get some incurable disease or become old, then there is no bigger wish for them than to live longer, put off the inevitable end. No matter what heavenly existence in the after‐life is promised to them by religion, the vast majority of people want to stay and enjoy life here, on Earth, as long as possible. In this paper, one possible way of personal immortality is discussed.
The effect of tube wall heat conduction on the natural convection in a long cylindrical envelope with an adiabatic lateral surface
Authors: Ya‐Ling He , Wen‐Jing Ding , Wen‐Quan Tao
Published: November 2004

The effect of the tube wall heat conduction on the natural convection in a tilted long cylindrical envelope with constant, but different temperature of the two ends and an adiabatic outer surface was numerically investigated. The envelope is supposed to be a simplified model for the pulse tube in a pulse tube refrigerator when the pulse tube is positioned at different orientations. It is found that the cylindrical envelope lateral wall heat conduction can enhance the heat transfer from the hot end to the cold end, not only because of the increase in pure heat conduction in the wall, but more importantly, also the intensification of the natural convection within the enclosure. This enhancement is resulted from the big temperature difference between the tube wall and the adjacent fluid near the hot and cold ends. Adoption of low thermal conductivity tube can effectively reduce such additional heat transfers from hot to cold end, thus reducing the loss of cooling capacity for the pulse tube refrigerator.
Easy and rapid computation of the transfer of heat from annular fins of nearly optimal profile with the finite‐difference technique and the shooting method
Authors: Campo Antonio , Morrone Biagio , Chikh Salah
Published: November 2004

It is undeniable that the annular fin of hyperbolic profile with constant thermal conductivity and uniform convective coefficient is important in many applications of heat transfer engineering. The importance of this fin configuration stems from its close resemblance to the annular fin of optimal cross section capable of delivering maximum heat transfer for a given volume of material. This paper addresses two simple numerical procedures for solving the generalized Bessel equation that governs the temperature variation in annular fins of hyperbolic profile, one is the finite‐difference technique with an uncharacteristic coarse mesh and the other is the shooting method. Certainly, the central objective here is to avoid the evaluation of the elegant, but intricate exact analytic temperature distributions and companion fin efficiencies containing modified Bessel functions of fractional order.
Dilemmas in the development of e‐learning at work
Authors: Christian Lahn Leif
Published: November 2004

How would a learning arena that promotes “just‐in‐time” learning in the workplace ideally be created? This was one of the most important questions the Norwegian research project, NEMLIG, aimed to illustrate through a series of work place experiments. The present article presents the evaluation of the project in the form of a number of dilemmas. These are clustered into three categories: those that related to present and future work organisation, those related to the user‐interface, and those dealing with user‐participation and systems development.
Knowledge flow transfers in multinational corporations: knowledge properties and implications for management
Authors: Ordóñez de Pablos Patricia
Published: November 2004

The aim of this paper is to analyze knowledge flows transfer within multinational corporations. In particular, it is focused on to what extent multinational companies can replicate headquarters’ human resource management systems in subsidiaries. This paper is structured into three major sections. The paper analyzes the transfer of knowledge flows in multinational companies. To analyze this “old problem” and shed light on its solution, the paper draws on the knowledge‐based view of the firm and reviews both seminal and recent contributions to this field of research. This paper develops a conceptual framework for the analysis of knowledge transfer at international level. It also examines the influence of four human resource management models (exported, adapted, hybrid and open models) on organizations. It addresses particular factors that influence the transferability of organizational knowledge such as the features of this knowledge and both organizational and national culture. Afterwards, these issues are addressed in the scenario of North‐American and Japanese multinational corporations. Multinational firms face important challenges in the actual economic environment. On the one hand, the firm must learn how to exploit its specific resources either acquired in the country of origin or in foreign markets. On the other hand, these firms cannot forget that the source of sustained competitive advantage takes place in the variety of skills and the diversity of knowledge, no in these resources homogeneity. Finally, multinational firms can benefit from international fertilization, because knowledge exploring and exploitation activities are closely relationed with the concepts of synergies, interdependence and interactive organizational learning. That is, the organizational capacity to innovate is the result of the interrelation among the units that form the firm. This paper offers a knowledge‐based view of the firm to help managers with the management of knowledge flows in multinational companies.
Identifying key knowledge area in the professional services industry: a case study
Authors: Cepeda Carrión Gabriel , Luis Galán González José , Leal Antonio
Published: November 2004

The purpose of this exploratory case study is to determine how an enterprise can identify and measure a key resource capability (critical knowledge area) to enhance competitive advantage, in the context of the emerging field of knowledge management. On the basis of the literature on resource capabilities and strategic management, the term critical knowledge area has been formulated as a label for a key resource capability.
Text clustering and summary techniques for CRM message management
Authors: Roussinov Dmitri , Leon Zhao J.
Published: November 2004

One of customer relationship management (CRM) activities involves soliciting customer feedback on product and service quality and the resolution of customer complaints. Inevitably, companies must deal with large number of CRM messages from their customers either through e‐mails or from work logs. Going through those messages is an important but tedious task for managers or CRM specialists in order to make strategic plans on where to place the resources to achieve better CRM results. In this paper, we present a methodology for making sense out of CRM messages based on text clustering and summary techniques. The unique features of CRM messages are the short message length and frequent availability of correlated CRM ratings. We propose several novel techniques including organizational concept space, Web mining of similarity relationships between concepts, and correlated analysis of text and ratings. We have tested the basic concepts and techniques of CRM Sense Maker in a business setting where customer surveys are used to set strategic directions in customer services.
The impact of e‐marketplaces on dyadic buyer‐supplier relationships: evidence from the healthcare sector
Authors: White A. , Daniel E.M.
Published: November 2004

This study seeks to explore the impact of e‐marketplaces on dyadic buyer‐supplier relationships in the healthcare sector. In particular it seeks to determine if the “move to the middle” hypothesis put forward by Clemons et al. will be supported in this domain. Case studies of four buying organisations in the healthcare sector (hospitals) and two suppliers (medical device companies), representing eight dyadic buyer supplier relationships were undertaken. It was found that the adoption of e‐marketplaces is associated with a reduction in the number of suppliers used by the buying organisations; a deepening of the relationship with the remaining suppliers and an increased “blurring of the boundaries” between the two parties.
INTERACTION OF NEURONAL POPULATIONS WITH DELAY: EFFECT OF FREQUENCY MISMATCH AND FEEDBACK GAIN
Authors: MENON V.
Published: November 2004

The effect of frequency mismatch, signal transduction delay and inter-population feedback gain on the interaction of neuronal populations, mediated by long-range excitation, is investigated using physiologically realistic system parameters.

Self-consistent solutions for the frequency, amplitude, and relative phase of the component signals are derived for limit cycle oscillations. These solutions predict important qualitative features including discontinuous changes in frequency of oscillation and phase reversal between symmetric and anti-symmetric limit cycles. A singularity in the solutions is used to predict parameter regions in which limit cycles do not exist. If limit cycles exist at zero delay, it is shown that limit cycles and quasi-periodic attractors alternate as a function of delay. The implications of these results for estimating physiologically meaningful delays from observed phase shifts in EEG time series are discussed.

Spectral peaks for the quasi-periodic attractor occur at mν1±nν2, where the difference ν1−ν2 is approximately equal to the intrinsic population frequency mismatch δν. The cross-correlation function is amplitude modulated with a frequency equal to δν/2, indicating that the two populations slip in and out of phase with a mean correlation duration equal to 1/δν. These findings underpin the dynamical basis of delay induced “desynchronization” of oscillations reported in computer simulations.

Bifurcation diagrams indicate that quasi-periodic attractors exist for a wide range of parameters in the presence of delay in long-range excitation and non-zero frequency mismatch. If the frequency mismatch is sufficiently large and the feedback gain is sufficiently small, quasi-periodic attractors exist for all delays. Delays of a few milliseconds, much smaller than the system time scale, can destabilize limit cycle oscillations. The role of synaptic change in inducing bifurcations of limit cycles to quasi-periodic attractors and vice versa is discussed. The implication of these findings for the generation of chaos in distributed neural systems is discussed.
HUMAN-LIKE DYNAMIC PROGRAMMING NEURAL NETWORKS FOR DYNAMIC TIME WARPING SPEECH RECOGNITION
Authors: CHIU CHINCHUAN , SHANBLATT MICHAEL A.
Published: November 2004

This paper presents a human-like dynamic programming neural network method for speech recognition using dynamic time warping. The networks are configured, much like human’s, such that the minimum states of the network’s energy function represent the near-best correlation between test and reference patterns. The dynamics and properties of the neural networks are analytically explained. Simulations for classifying speaker-dependent isolated words, consisting of 0 to 9 and A to Z, show that the method is better than conventional methods. The hardware implementation of this method is also presented.
ON THE FUNCTIONAL EQUIVALENCE OF FUZZY INFERENCE SYSTEMS AND SPLINE-BASED NETWORKS
Authors: HUNT K.J. , HAAS R. , BROWN M.
Published: November 2004

The conditions under which spline-based networks are functionally equivalent to the Takagi-Sugeno-model of fuzzy inference are formally established. We consider a generalized form of basis function network whose basis functions are splines. The result admits a wide range of fuzzy membership functions which are commonly encountered in fuzzy systems design. We use the theoretical background of functional equivalence to develop a hybrid fuzzy-spline net for inverse dynamic modeling of a hydraulically driven robot manipulator.
A PERSPECTIVE AND CRITIQUE OF ADAPTIVE NEUROFUZZY SYSTEMS USED FOR MODELLING AND CONTROL APPLICATIONS
Authors: BROWN M. , HARRIS C.J.
Published: November 2004

This paper outlines some of the theoretical and practical developments being made in neurofuzzy systems. As the name suggests, neurofuzzy networks were developed by fusing the ideas that originated in the fields of neural and fuzzy systems. A neurofuzzy network attempts to combine the transparent, linguistic, symbolic representation associated with fuzzy logic with the architecture and learning rules commonly used in neural networks. These hybrid structures have both a qualitative and a quantitative interpretation and can overcome some of the difficulties associated with solely neural algorithms which can usually be regarded as black box mappings, and with fuzzy systems where few modelling and learning theories existed. Both B-spline and Gaussian Radial Basis Function networks can be regarded as neurofuzzy systems and soft inductive learning algorithms can be used to extract unknown, qualitative information about the relationships contained in the training data. In a similar manner, qualitative rules or information about the network’s structure can be used to initialise the system. These areas, coupled with the extensive work being carried out on theoretically analysing their modelling, convergence and stability properties means that this research topic is highly applicable in “intelligent” modelling and control problems. Apart from outlining this work, the paper also discusses a wide variety of open research questions and suggests areas where new efforts may be fruitfully applied.
METHODS OF TRAINING AND CONSTRUCTING MULTILAYER PERCEPTRONS WITH ARBITRARY PATTERN SETS
Authors: LIANG XUN , XIA SHAOWEI
Published: November 2004

This paper presents two compensation methods for multilayer perceptrons (MLPs) which are very difficult to train by traditional Back Propagation (BP) methods. For MLPs trapped in local minima, compensating methods can correct the wrong outputs one by one using constructing techniques until all outputs are right, so that the MLPs can skip from the local minima to the global minima. A hidden neuron is added as compensation for a binary input three-layer perceptron trapped in a local minimum; and one or two hidden neurons are added as compensation for a real input three-layer perceptron. For a perceptron of more than three layers, the second hidden layer from behind will be temporarily treated as the input layer during compensation, hence the above methods can also be used. Examples are given.
NEURAL NETWORK BASED DYNAMIC CONTROLLERS FOR INDUSTRIAL ROBOTS
Authors: OH SE-YOUNG , SHIN WEON-CHANG , KIM HYO-GYU
Published: November 2004

The industrial robot’s dynamic performance is frequently measured by positioning accuracy at high speeds and a good dynamic controller is essential that can accurately compute robot dynamics at a servo rate high enough to ensure system stability. A real-time dynamic controller for an industrial robot is developed here using neural networks. First, an efficient time-selectable hidden layer architecture has been developed based on system dynamics localized in time, which lends itself to real-time learning and control along with enhanced mapping accuracy. Second, the neural network architecture has also been specially tuned to accommodate servo dynamics. This not only facilitates the system design through reduced sensing requirements for the controller but also enhances the control performance over the control architecture neglecting servo dynamics. Experimental results demonstrate the controller’s excellent learning and control performances compared with a conventional controller and thus has good potential for practical use in industrial robots.
RECOGNITION OF TELUGU CHARACTERS USING NEURAL NETWORKS
Authors: SUKHASWAMI M.B. , SEETHARAMULU P. , PUJARI ARUN K.
Published: November 2004

The aim of the present work is to recognize printed and handwritten Telugu characters using artificial neural networks (ANNs). Earlier work on recognition of Telugu characters has been done using conventional pattern recognition techniques. We make an initial attempt here of using neural networks for recognition with the aim of improving upon earlier methods which do not perform effectively in the presence of noise and distortion in the characters. The Hopfield model of neural network working as an associative memory is chosen for recognition purposes initially. Due to limitation in the capacity of the Hopfield neural network, we propose a new scheme named here as the Multiple Neural Network Associative Memory (MNNAM). The limitation in storage capacity has been overcome by combining multiple neural networks which work in parallel. It is also demonstrated that the Hopfield network is suitable for recognizing noisy printed characters as well as handwritten characters written by different “hands” in a variety of styles. Detailed experiments have been carried out using several learning strategies and results are reported. It is shown here that satisfactory recognition is possible using the proposed strategy. A detailed preprocessing scheme of the Telugu characters from digitized documents is also described.
NONLINEAR GATED EXPERTS FOR TIME SERIES: DISCOVERING REGIMES AND AVOIDING OVERFITTING
Authors: WEIGEND ANDREAS S. , MANGEAS MORGAN , SRIVASTAVA ASHOK N.
Published: November 2004

In the analysis and prediction of real-world systems, two of the key problems are nonstationarity (often in the form of switching between regimes), and overfitting (particularly serious for noisy processes). This article addresses these problems using gated experts, consisting of a (nonlinear) gating network, and several (also nonlinear) competing experts. Each expert learns to predict the conditional mean, and each expert adapts its width to match the noise level in its regime. The gating network learns to predict the probability of each expert, given the input. This article focuses on the case where the gating network bases its decision on information from the inputs. This can be contrasted to hidden Markov models where the decision is based on the previous state(s) (i.e. on the output of the gating network at the previous time step), as well as to averaging over several predictors. In contrast, gated experts soft-partition the input space, only learning to model their region.

This article discusses the underlying statistical assumptions, derives the weight update rules, and compares the performance of gated experts to standard methods on three time series: (1) a computer-generated series, obtained by randomly switching between two nonlinear processes; (2) a time series from the Santa Fe Time Series Competition (the light intensity of a laser in chaotic state); and (3) the daily electricity demand of France, a real-world multivariate problem with structure on several time scales. The main results are: (1) the gating network correctly discovers the different regimes of the process; (2) the widths associated with each expert are important for the segmentation task (and they can be used to characterize the sub-processes); and (3) there is less overfitting compared to single networks (homogeneous multilayer perceptrons), since the experts learn to match their variances to the (local) noise levels. This can be viewed as matching the local complexity of the model to the local complexity of the data.
ON THE SYSTEM SIZE OF LATTICE BOLTZMANN SIMULATIONS
Authors: MAYER GUSZTÁV , HÁZI GÁBOR , PÁLES JÓZSEF , IMRE ATTILA R. , FISCHER BJÖRN , KRASKA THOMAS
Published: November 2004

In lattice Boltzmann simulations particle groups — represented by scalar velocity distributions — are moved on a finite lattice. The size of these particle groups is not well-defined although it is crucial to assume that they should be big enough for using a continuous distribution. Here we propose to use the liquid–vapor interface as an internal yardstick to scale the system. Comparison with existing experimental data and with molecular dynamics simulation of Lennard–Jones-argon shows that the number of atoms located on one lattice site is in the order of few atoms. This contradicts the initial assumption concerning the number of particles in the group, therefore seems to raise some doubts about the applicability of the lattice Boltzmann method in certain problems whenever interfaces play important role and ergodicity does not hold.
TESTING THE TURING TEST — DO MEN PASS IT?
Authors: ADAM RUTH , HERSHBERG URI , SCHUL YAACOV , SOLOMON SORIN
Published: November 2004

We are fascinated by the idea of giving life to the inanimate. The fields of Artificial Life and Artificial Intelligence (AI) attempt to use a scientific approach to pursue this desire. The first steps on this approach hark back to Turing and his suggestion of an imitation game as an alternative answer to the question "can machines think?".1To test his hypothesis, Turing formulated the Turing test1to detect human behavior in computers. But how do humans pass such a test? What would you say if you would learn that they do not pass it well? What would it mean for our understanding of human behavior? What would it mean for our design of tests of the success of artificial life? We report below an experiment in which men consistently failed the Turing test.
SPECIALIZED MEASURES OF LEAF OUTLINES AND HIERARCHICAL PERCEPTRONS IN AN AUTOMATIC IDENTIFICATION OF PLANTS
Authors: BORKOWSKI WOJCIECH , KOSTRZYŃSKA LIDIA
Published: November 2004

The development of an efficient image-based computer identification system for plants or other organisms is an important ambitious goal, which is still far from realization. This paper presents three new methods potentially usable for such a system: fractal-based measures of complexity of leaf outline, a heuristic algorithm for automatic detection of leaf parts — the blade and the petiole, and a hierarchical perceptron — a kind of neural network classifier. The next few sets of automatically extractable features of leaf blades, encompassed those presented and/or traditionally used, are compared in the task of plant identification using the simplest known "nearest neighbor" identification algorithm, and more realistic neural network classifiers, especially the hierarchical. We show on two real data sets that the presented techniques are really usable for automatic identification, and are worthy of further investigation.
HOW SPACETIME FOAM MODIFIES THE BRICK WALL
Authors: GARATTINI REMO
Published: November 2004

We re-examine the brick-wall model in the context of spacetime foam. In particular we consider a foam composed by wormholes of different sizes filling the black hole horizon. The contribution of such wormholes is computed via a scale-invariant distribution. We obtain that the brick wall divergence appears to be logarithmic when the cutoff is sent to zero.
STABILITY OF MONOPOLE CONDENSATION IN SU(2) QCD
Authors: CHO Y. M. , WALKER M. L.
Published: November 2004

We propose to resolve the controversy regarding the stability of the monopole condensation in QCD by calculating the imaginary part of the one-loop effective action perturbatively. We calculate the imaginary part perturbatively to the order g2 with two different methods, with Feynman diagram and with Schwinger's method. Our result shows that with the magnetic background the effective action has no imaginary part, but with the electric background it acquires a negative imaginary part. This strongly indicates a stable monopole condensation in QCD.
CIRCULAR ORBITS AROUND SCHWARZSCHILD–AdS SPACETIME
Authors: DE M. CARVALHO A. M. , FURTADO CLAUDIO , MORAES FERNANDO
Published: November 2004

In this paper we discuss parallel transport of vectors and spinors around circular orbits in Schwarzschild–AdS spacetime. We study the global properties of this spacetime via loop variables or holonomy. A set of paths in this background is considered. We demonstrate that for some special radii there appears the so-called quantized band structure of holonomy invariance. This analysis is also extended to parallel transport of a spinor in this spacetime.
ON LEADING CHARMED MESON PRODUCTION IN π–NUCLEON INTERACTIONS
Authors: BEDNYAKOV V. A.
Published: November 2004

It is shown that the D-meson, whose light quark is the initial-pion valence quark and whose charmed quark is produced in annihilation of valence quarks and has got a large enough momentum, is really a leading meson in reactions like π−p → DX. If such annihilation of valence quarks from initial hadrons is impossible there must be no distinct leading effect.