bluuebunny/crossref_metadata_2025_split huggingface dataset:
A VoIP communication system for advanced public networks
Authors: Watanabe Nobuyuki , Kishida Koji 
Published: December 2005

AbstractWith recent advances in IP‐related technology, VoIP, which can provide cheaper communications than conventional telephone networks, is attracting interest. Communication within IP networks has already been established in practice. In the early stage of introduction of the technology into the public network, VoIP and conventional tele‐phony coexist, and it is important in spreading the use of VoIP that interconnection to the existing network should be achieved. Furthermore, in order to promote the shift from telephone to VoIP, the existing telephone service should be available. These functions of interconnection and the existing service are resources of the PSTN exchange system, and it is inefficient if a new VoIP system is developed without utilizing these resources. Consequently, this paper proposes an architecture for the Call Agent system in which the above functions and the VoIP function are achieved by extending the PSTN switching software. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 89(4): 52–60, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.10229
A method of interconnection between private VoIP networks and PSTN
Authors: Nasuno Yutaka , Ouchi Tsutomu , Kazami Hiroshi , Tarumoto Naoki , Tokita Masahiko , Arai Ken Ichi 
Published: December 2005

AbstractThe use of IP telephony is spreading rapidly. It was developed chiefly for general home use, and mainly supports calls to the PSTN. In such a service configuration, various problems of realizing telephone service, such as the network address translation (NAT) problem, have generally been solved by the use of a terminal specified by the service provider. On the other hand, the design of origination/destination services between VoIP in enterprise private networks and the PSTN involves various problems, including the solution of the NAT problem, and the requirements differ considerably from those of IP telephony for general home use. This paper presents a method of solution of the technical problems related to interconnection between VoIP and PSTN in enterprise IP networks. The solution is the result of investigations emphasizing the practical aspect and repeated verification experiments, and is applicable to real commercial services. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 89(4): 42–51, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20197
Development of cellular repeater system with radio echo suppresser
Authors: Maeyama Toshiyuki , Inoue Takashi 
Published: December 2005

AbstractThe authors have developed a method of suppressing the radio echo generated by the coupling of transmitting and receiving antennas at the repeater station for a cellular system that repeats wireless signals at the same frequency. The method includes a function to automatically detect and suppress the radio echo generated by reflection from buildings near the repeater as well as the direct coupling between the transmitting and receiving antennas. A repeater for cdma2000 based on this scheme is fabricated, with the antenna of the repeater pointed to the base station and the antenna pointed to the mobile station installed on the same pillar. When the interference suppression function is activated, it is found that the repeater gain of the repeater may exceed 80 dB. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 89(4): 32–41, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20200
Performance of channel estimation schemes for multicarrier systems
Authors: Taira Akinori , Hara Yoshitaka , Ishizu Fumio , Murakami Keishi 
Published: December 2005

AbstractThis paper considers a multicarrier system performing burst transmission and discusses the channel estimation method, together with the estimation accuracy. In a multicarrier system such as OFDM, the channel state information of each subcarrier is estimated using a known signal, and then the signal is detected. Consequently, the accuracy of channel estimation has a large effect on transmission performance. Furthermore, in an MC‐CDMA system in which OFDM is combined with code spreading in the frequency domain, the signal is also synthesized by using subcarriers in the receiver on the basis of the subchannel information. Thus, the signal quality after despreading depends greatly on the accuracy of channel estimation, and it is an important issue to establish a channel estimation method suited to a multicarrier system and to evaluate its accuracy. This paper considers channel estimation in the time domain based on correlation calculation for the known signal and channel estimation in the frequency domain using the FFT of the known signal. The accuracy of estimation is derived analytically, and a method of reducing the computational complexity is proposed. Finally, the receiver performance is derived quantitatively by computer simulation, assuming that these channel estimation procedures are applied, and the effects of these methods on the quality of the received signal are analyzed. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 89(4): 10–21, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20261
Proposal of a global conversion method for different integration time rain rates by using M distribution and regional climatic parameters
Authors: Ito Chieko , Hosoya Yoshio 
Published: December 2005

AbstractThe most serious transmission impairment is caused by rain on radio links using frequencies above about 10 GHz. Thus, in the system design, it is required to predict the rain attenuation distribution for the radio link, and accordingly it is necessary to know one‐minute rain rate distributions. In this paper, using the databank created at Kitami Institute of Technology, a novel method for conversion between rain rates with different integration times is proposed. This method uses the M distribution and the regional climatic parameters. It was found that this method is applicable with good accuracy for any integration time and any location in the world. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 89(4): 1–9, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20270
Real‐time recognition of multiple pedestrians using car‐mounted camera
Authors: Suzuki Hidekazu , Minami Mamoru 
Published: December 2005

AbstractIn ITS, there has recently been emphasis on the importance of developing a driving assistance system which can detect pedestrians with a car‐mounted camera and warn of their presence in order to assure pedestrian safety. In particular, the ability to detect multiple pedestrians in real time (at a video rate of 30 fps) is indispensable from the practical point of view. Consequently, this study proposes a method of recognizing multiple moving objects (pedestrians) in real time using dynamic scene input from a car‐mounted camera, as a basic technology for the driving assistance system. The presence of a pedestrian is evaluated on the basis of hue information in the HSI color representation system and model‐based matching using a circular approximation model. Thus, in terms of the evaluation function, the problem of recognition of multiple pedestrians is replaced by the problem of search for multiple local maxima. However, it is difficult to realize the process in real time if the evaluation value is calculated for the whole image. This paper considers the “attention,” which is a function that reduces the burden of human visual information processing, and proposes a method in which a pseudo‐attention function is realized by using a hybrid GA, allowing multiple local maxima to be retrieved efficiently in real time.A real‐time experiment on the recognition of multiple pedestrians in dynamic images obtained from a car‐mounted camera was used to verify the effectiveness of the proposed method. In addition, the practical performance of the system was investigated by an experiment on the recognition of suddenly appearing pedestrians. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 89(4): 21–33, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20181
Characteristics of alpha wave response to flicker stimuli with color alternation
Authors: Nishifuji Seiji , Ohkado Hironori , Tanaka Shogo 
Published: December 2005

AbstractSpatiotemporal responses of the alpha wave to flicker stimuli with temporal alternation of two stimulus colors are investigated and compared to the properties of the alpha wave at rest and in response to single‐color stimuli in order to evaluate the effect of the alternation of stimulus colors on the electroencephalogram. The alpha wave can be entrained by all kinds of flicker stimuli, that is, the frequency of the alpha wave shifts to that of the stimuli. The spatial distributions of the amplitude and phase difference on presentation of alternating red/blue stimuli show anomalous spatial characteristics for more than half the subjects, namely, a large amplitude in the centro‐parietal region and the same phase over the entire scalp, whereas those under other stimuli show large amplitude in the occipital and frontal regions and opposite phase in the frontal and occipital regions. The results may provide useful information for considering the effect of color alternation of flicker stimuli on the electroencephalogram, as well as for modeling the generating mechanism of alpha waves. They may also be useful for evaluating the effect of color alternation in photic stimuli, such as video images and animations, on the electroencephalogram. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 89(4): 1–10, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20204
Quantitative evaluation of walking style from the temporal and spatial tracks of sole pressure points
Authors: Sudo Kyoko , Shimada Satoshi , Iida Yukiyasu , Takahashi Yasuko , Ohtsuka Sakuichi 
Published: December 2005

AbstractFor effective guidance of walking, the authors developed a quantitative method for evaluating the quality of walking based on physical feature parameters reflecting the views of specialists in walking guidance. The concept of “quality of walking” comprises foot movement, balance, including the upper body, and the aesthetic aspect. This study focuses on foot movement, which allows easy relation of subjective evaluation and physical features. Specifically, two physical features were investigated, which are considered the important requirements in assuring balance in foot movement. They are (1) supination of the sole (after the heel strike, the center of gravity passes slightly outside the body) and (2) rolling (the sole is used successively from heel to toe). The track of the sole pressure point was measured with a pressure sensor, and the difference between the instructor and the learner was represented by spatial and temporal feature parameters. The multiple regression equations for the two feature parameters and the comprehensive evaluation by visual inspection by the instructor were compared. It was found that these feature parameters are useful as evaluation parameters for the quality of walking (with a contribution ratio of approximately 50%). An experimental evaluation device for walking with the data visualization tool was constructed, which implements the estimation function for the quality of walking. It is found that the device can be helpful in the actual guidance of walking. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 3, 89(4): 42–54, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjc.20237
Ring Opening and Displacement by Chloride of the Bidentate Chelate Ligand from Dichloro[pyridine‐2‐(α‐methoxymethanolato)]gold(III) – A Kinetic and Mechanistic Study
Authors: Marangoni Giampaolo , Pitteri Bruno , Annibale Giuliano , Bortoluzzi Marco 
Published: December 2005

AbstractThe kinetics of ring opening and displacement of the bidentate chelate ligand from dichloro[pyridine‐2‐(α‐methoxymethanolato)]gold(III) [Au(N–O)Cl2] (1) have been studied spectrophotometrically in methanol/water (95:5, v/v) at 25 °C and constant ionic strength (I = 1 mol dm–3, LiClO4). In the presence of LiCl and perchloric acid the reaction consists of a pre‐equilibrium protonation of the coordinated oxygen followed first by ring opening at oxygen accompanied by the entry of chloride or solvent and fast acetalisation of the hemiacetalic form of the ligand to give [AuCl3(N–OMe)], and then by displacement of the N‐bonded ligand to give [AuCl4]–. The ligand is not displaced in the absence of chloride and no reaction is observed in the presence of chloride alone.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Adaptive discontinuous Galerkin methods with shock‐capturing for the compressible Navier–Stokes equations
Authors: Hartmann R. 
Published: December 2005

AbstractWe present the Interior Penalty discontinuous Galerkin method for the compressible Navier–Stokes equations. Shock‐capturing is used to reduce over‐shoots at discontinuities and sharp gradients. This stabilization introduces artificial viscosity at places of large local residuals, but preserves conservation and Galerkin orthogonality of the DG method. Based on this discretization we derive a posteriori error estimates for the error measured in terms of arbitrary target functionals, like, e.g. the drag and lift coefficients of an airfoil immersed in a viscous or inviscid fluid.The performance of the nonlinear solution process, the a posteriori error estimation and an adaptive mesh refinement specially tailored for the accurate computation of the force coefficients are demonstrated for supersonic laminar flows around the NACA0012 airfoil. Copyright © 2005 John Wiley & Sons, Ltd.
Numerical simulation of sand dune evolution in severe winds
Authors: Ortiz Pablo , Smolarkiewicz Piotr K. 
Published: December 2005

AbstractWe present a novel approach for numerical simulation of fluid flow and sediment transport past evolutionary landforms, with emphasis on sand dunes developing in extreme winds. Time‐dependent curvilinear coordinates are employed to fully couple flow aloft with the developing landform. The conservation law that defines shape of the lower boundary depends on details of local surface stress, thereby favouring a large eddy simulation of the atmospheric boundary layer. The flux‐form partial differential equation for the interface profile—via saltation and sand avalanches—is formulated as an advection–diffusion equation. The latter facilitates discrete integrations using nonoscillatory algorithms—consistent with the nonoscillatory forward‐in‐time solver, based on MPDATA transport methods, employed to simulate the boundary layer flow aloft. Theoretical discussions are illustrated with numerical experiments that explore the interactive evolution of the dune/atmosphere system. Copyright © 2005 John Wiley & Sons, Ltd.
Numerical simulations of interfacial instabilities on a rotating miscible droplet in a time‐dependent gap Hele–Shaw cell with significant Coriolis effects
Authors: Chen Chen‐Hua , Chen Ching‐Yao 
Published: December 2005

AbstractInterfacial instability of a rotating miscible droplet with significant Coriolis force in a Hele–Shaw cell is simulated numerically. The influences of the relevant control parameters are first discussed qualitatively by fingering patterns. More vigorous fingerings are found at higher rotational effects, a lower viscosity contrast and a weaker effective surface tension (Korteweg constant). For a time‐dependent gap Hele–Shaw cell, a higher cell lifting rate makes the rotating droplet bear an inward straining flow, which leads to fingering enhancement. On the contrary, a higher pressing rate provides more stable effects by additional squeezing outward flow. A quantitative analysis between the Coriolis effects and tilting angles of fingers is addressed. For arbitrary combinations of all relevant control parameters, the values of tilting angles follow a nearly linear relationship with the Coriolis effects. We estimate the correlation between the relevant control parameters (dimensionless Coriolis factor Re, viscosity parameter R, cell lifting rate a) and tilting angles (θ) of fingers that can be approximated as $\theta = (0.0047\sqrt {Pe/R} + 18.2a)Re$ for significant Korteweg stresses. Copyright © 2005 John Wiley & Sons, Ltd.
A numerical study of fully developed laminar flows in pipes with two planar curvatures
Authors: Niewiadomski C. , Paraschivoiu M. , Sullivan P. 
Published: December 2005

AbstractThe spectral element method is applied on unstructured tetrahedral elements to solve the Navier–Stokes equations for fully developed laminar flow in pipes with two planar curvatures. Specific implementations of the spectral element method to double curved pipes and parallelization are described. Previous studies on flows in pipes focused on constant curvature or torsion geometries, as well as pipes with varying curvature. This study focuses on the periodic variation of both the curvature as well as torsion by analysing a pipe having two planar curvatures. The effects of the three parameters defining the pipe are studied to isolate the curvature and torsion effect on the magnitude and angle of the secondary flow. Furthermore, the geometric effects on the wall shear stress are studied, as it is an important fluid flow property, especially in blood flows. Copyright © 2006 John Wiley & Sons, Ltd.
MPDATA and grid adaptivity in geophysical fluid flow models
Authors: Prusa J. M. , Gutowski W. J. 
Published: December 2005

AbstractGeophysical flows can profoundly affect human activities. Often characterized by an astonishing range of significant scales and a rich assortment of physical processes, the complexity of such flows generally precludes all but numerical simulation for prediction and understanding—yet even state of the art computational models may be severely challenged by problems such as hurricane intensification. Although a number of significant issues are involved, a major factor is often grid resolution, for which grid adaptivity (GA) can be useful. Our experience has been that MPDATA is particularly well suited for GA. This paper sketches general details of a model that blends MPDATA with continuous GA; highlights a tensor viewpoint of the geometric conservation law; and presents results for both global and regional atmospheric applications. Together, the examples demonstrate the advantages of using GA with MPDATA to resolve fine‐scale features—explicit gravity waves generated by flow over orography. Resolution of these waves (or lack thereof) are shown to affect global climate; furthermore, wave resolution is shown to depend upon the regional atmospheric environment. Finally the regional simulations show a surprising increase in the complexity of the wavefields as resolution is increased to the point of resolving nonhydrostatic effects. Copyright © 2005 John Wiley & Sons, Ltd.
A modified space–time finite element method for simulation of immiscible incompressible two‐phase flow in heterogeneous porous media
Authors: Ferdowsi P. A. , Manzari Mehrdad T. 
Published: December 2005

AbstractIn this paper, a modified space–time method is presented for the simulation of convection–diffusion equations. The new method differs from the original space–time method in the sense that the weight functions for space and time are different. The performance of the proposed algorithm is studied for numerical simulation of incompressible immiscible two‐phase flow in porous media. The governing equations consist of one conservation of mass equation for each phase, the Darcy law and one capillary‐saturation correlation for the flow. By defining a global pressure, the governing equations lead to a system of nonlinear equations in terms of this global pressure, the velocity components and the saturation of one phase. The flow equations are solved for the global pressure and velocity components using a stabilized mixed finite element method while the saturation equation is solved by the standard and modified space–time element methods. The performance of the proposed space–time method is compared with that of the original Petrov–Galerkin space–time method for both linear and nonlinear cases. The effect of the tuning parameters of the standard method, grid size and the capillary pressure are studied for a one‐dimensional problem. A stability analysis is also carried out for the proposed space–time method. Finally, to demonstrate the capability of the proposed method in dealing with homogeneous and heterogeneous problems two‐dimensional water‐flooding five‐spot test cases are studied. Copyright © 2005 John Wiley & Sons, Ltd.
Regional activation of chromosomal arm 7q with and without gene amplification in taxane‐selected human ovarian cancer cell lines
Authors: Wang Yan C. , Juric Dejan , Francisco Brian , Yu Ron X. , Duran George E. , Chen Kevin G. , Chen Xin , Sikic Branimir I. 
Published: December 2005

AbstractTaxanes are important drugs in the treatment of ovarian and other cancers, but their efficacy is limited by intrinsic and acquired drug resistance. Expression of the multidrug transporter P‐glycoprotein, encoded by the MDR1 (ABCB1) gene, is one of the causes of clinical drug resistance to taxanes. To study the mechanisms of MDR1 activation related to taxanes, we established 11 multidrug‐resistant variants from six ovarian cancer cell lines by continuous exposure to either paclitaxel or docetaxel. We profiled gene expression and gene copy number alterations in these cell lines using cDNA microarrays and identified a cluster of genes coactivated with MDR1 in 7q21.11–13. Regional activation was evident in nine resistant variants displaying a coexpression pattern of up to 22 genes over an 8‐Mb area, including SRI, MGC4175, CLDN12, CROT, and CDK6. In six of these variants, regional activation was driven by gene copy number alterations, with low‐level gains or high‐level amplifications spanning the involved region. However, three variants displayed regional increases in gene expression even without concomitant gene copy number changes. These results suggest that regional gene activation may be a fundamental mechanism for acquired drug resistance, with or without changes in gene dosage. In addition to numerical and structural chromosomal changes driven by genome instability in cancer cells, other mechanisms might be involved in MDR1 regional activation, such as chromatin remodeling and DNA or histone modifications of the 7q21 region. This article contains Supplementary Material available at http://www.interscience.wiley.com/jpages/1045‐2257/suppmat. © 2005 Wiley‐Liss, Inc.