bluuebunny/crossref_metadata_2025_split huggingface dataset:
Collo‐diaphysial angle of the femur in East African subjects
Authors: Igbigbi P.S. 
Published: August 2003

AbstractThe collo‐diaphysial angle of East African subjects was investigated using 860 unilateral anteroposterior radiographs of the hip from 400 Ugandan and 460 Kenyan subjects, aged between 18 and 65 years using the standard techniques of Singh and Singh (1975). The angle ranged from 125–144° with a mean of 133.3° and a standard deviation (SD) of 5.3° for Ugandan males; and 119–139°, mean 123.4°, SD 5.8° for Ugandan females. The Kenyan values were 125–159°, mean 140.2°, SD 6.2° for males; and 117–134°, mean 125.7°, SD 5.1° for females, respectively. There were significant differences between males and females in both groups as well as between Ugandan and Kenyan males (P < 0.05). Using the demarking points method, only 19.0% of male Ugandans, 41.7% of male Kenyans, and 18.2% of female Kenyans could be identified by gender. This study documents for the first time the collo‐diaphysial angle of East African subjects and has further confirmed that the angle is wider in men than women. Clin. Anat. 16:416–419, 2003. © 2003 Wiley‐Liss, Inc.
Echocardiographic and morphologic examination of left ventricular false tendons in human and animal hearts
Authors: Kervancioğlu M. , Őzbağ D. , Kervancioğlu P. , Hatipoğlu E.S. , Kilinç M. , Yilmaz F. , Deniz M. 
Published: August 2003

AbstractFalse tendons are thin, fibrous or fibromuscular structures that traverse the cavity of the left ventricle with no connection to the valvular cusps; they may be single or multiple. We retrospectively analyzed echocardiograms for the prevalence of false tendons in the hearts of 368 (231 male, 137 female) newborns, infants, and children (mean age = 6.28 ± 4.32 years) who were referred for echocardiography because of suspected acquired or congenital heart disease, but in whom no cardiac pathology was found. In addition, we studied the prevalence of false tendons in 90 hearts from three species of animals (dog, sheep, goat) and eight cadaveric human hearts. In our echocardiographic study, false tendons were detected in 97 of 368 hearts (26.4%). In our gross morphologic studies, false tendons were observed in most of the animal and human hearts: they were present in 5 of 8 (62.5%) human hearts, 14 of 20 (70%) dog hearts, 41 of 50 (82%) sheep hearts, and 16 of 20 (80%) goat hearts. The overall prevalence in animal hearts was 71 of 90 (78.8%). Histologic examination showed the false tendons to be composed of cardiac muscle, blood vessels, fibrous tissue, and Purkinje cells. The possible role of false tendons in innocent murmurs, cardiac rhythm disorders, or left ventricular dysfunction is discussed. Clin. Anat. 16:389–395, 2003. © 2003 Wiley‐Liss, Inc.
Scalable causal message logging for wide‐area environments
Authors: Bhatia Karan , Marzullo Keith , Alvisi Lorenzo 
Published: August 2003

AbstractWide‐area systems are gaining in popularity as an infrastructure for running scientific applications. From a fault tolerance perspective, these environments are challenging because of their scale and their variability. Causal message logging protocols have attractive properties that make them suitable for these environments. They spread fault tolerance information around in the system providing high availability. This information can also be used to replicate objects that are otherwise inaccessible because of network partitions.However, current causal message logging protocols do not scale to thousands or millions of processes. We describe the Hierarchical Causal Message Logging Protocol (HCML) that uses a hierarchy of shared logging sites, or proxies, to significantly reduce the space requirements as compared with existing protocols. These proxies also act as caches for fault tolerance information and reduce the overall message overhead by as much as 50%. HCML also leverages differences in bandwidth between processes that reduces overall message latency by as much as 97%. Copyright © 2003 John Wiley & Sons, Ltd.
Achieving portable and efficient parallel CORBA objects
Authors: Denis Alexandre , Pérez Christian , Priol Thierry 
Published: August 2003

AbstractWith the availability of Computational Grids, new kinds of applications are emerging. They raise the problem of how to program them on such computing systems. In this paper, we advocate a programming model based on a combination of parallel and distributed programming models. Compared to previous approaches, this work aims at bringing single program multiple data (SPMD) programming into CORBA in a portable way. For example, we want to interconnect two parallel codes by CORBA without modifying either CORBA or the parallel communication API. We show that such an approach does not entail any loss of performance compared to previous approaches that required modification to the CORBA standard. Moreover, using an ORB that is able to exploit high‐performance networks, we show that portable parallel CORBA objects can efficiently make use of such networks. Copyright © 2003 John Wiley & Sons, Ltd.
HA‐PSLS: a highly available parallel single‐level store system
Authors: Kermarrec Anne‐Marie , Morin Christine 
Published: August 2003

AbstractParallel single‐level store (PSLS) systems integrate a shared virtual memory and a parallel file system. They provide programmers with a global address space including both memory and file data. PSLS systems implemented in a cluster thus represent a natural support for long‐running parallel applications, combining both the natural shared memory programming model and a large and efficient file system.However, the need to tolerate failures in such a system increases with the size of applications. In this paper we present a highly‐available parallel single level store system (HA‐PSLS), which smoothly integrates a backward error recovery high‐availability mechanism into a PSLS system. Our system is able to tolerate multiple transient failures, a single permanent failure, and power cut failures affecting the whole cluster, without requiring any specialized hardware. For this purpose, HA‐PSLS relies on a high degree of integration (and reusability) of high‐availability and standard features. A prototype integrating our high‐availability support has been implemented and we show some performance results in the paper. Copyright © 2003 John Wiley & Sons, Ltd.
A distributed object infrastructure for interaction and steering
Authors: Muralidhar Rajeev , Parashar Manish 
Published: August 2003

AbstractThis paper presents the design, implementation and experimental evaluation of DIOS (Distributed Interactive Object Substrate), an interactive object infrastructure to enable the runtime monitoring, interaction and computational steering of parallel and distributed applications. DIOS enables application objects (data structures, algorithms) to be enhanced with sensors and actuators so that they can be interrogated and controlled. Application objects may be distributed (spanning many processors) and dynamic (be created, deleted, changed or migrated). Furthermore, DIOS provides a control network that interconnects the interactive objects in a parallel/distributed application and enables external discovery, interrogation, monitoring and manipulation of these objects at runtime. DIOS is currently being used to enable interactive visualization, monitoring and steering of a wide range of scientific applications, including oil reservoir, compressible turbulence and numerical relativity simulations. Copyright © 2003 John Wiley & Sons, Ltd.
Winner‐relaxing and winner‐enhancing Kohonen maps: Maximal mutual information from enhancing the winner
Authors: Claussen Jens Christian 
Published: August 2003

AbstractThe magnification behavior of a generalized family of self‐organizing feature maps, the winner relaxing and winner enhancing Kohonen algorithms is analyzed by the magnification law in the one‐dimensional case, which can be obtained analytically. The winner‐enhancing case allows to achieve a magnification exponent of one and therefore provides optimal mapping in the sense of information theory. A numerical verification of the magnification law is included, and the ordering behavior is analyzed. Compared to the original self‐organizing map and some other approaches, the generalized winner enforcing algorithm requires minimal extra computations per learning step and is conveniently easy to implement. © 2003 Wiley Periodicals, Inc.
Significance of joint‐spike events based on trial‐shuffling by efficient combinatorial methods
Authors: Pipa Gordon , Diesmann Markus , Grün Sonja 
Published: August 2003

AbstractThe assembly hypothesis suggests that information processing in the cortex is mediated by groups of neurons expressed by their coordinated spiking activity. Thus, the unitary events analysis was designed to detect the presence of conspicuous joint‐spike events in multiple single‐unit recordings and to evaluate their statistical significance. The null hypothesis of the associated test assumes independent Poisson processes and leads to parametric significance estimation. In order to allow for arbitrary processes here we suggest to base the significance estimation on trial shuffling and resampling. In this scheme the null hypothesis is implemented by combining spike trains from nonsimultaneous trials and counting the joint‐spike events. The coincidence distribution serving for the significance estimation is generated by repetitive resampling. The number of all possible recombinations, however, grows dramatically with the number of trials and neurons and thus is not practical for a user‐interactive implementation of the analysis. We have suggested a Monte‐Carlo‐based resampling procedure and demonstrated that the procedure yields an appropriate estimate of the distribution and reliable significance estimation. In contrast, here, we present an exact solution. Rewriting the statistical problem in terms of certain macrostates, we are able to systematically sample the coincidence counts from all trial combinations. In addition we restrict the generating process to those counts forming the relevant tail of the distribution. The computationally effective implementation uses the concept of partitions. © 2003 Wiley Periodicals, Inc.
Complex dynamics is abolished in delayed recurrent systems with distributed feedback times
Authors: Thiel Andreas , Schwegler Helmut , Eurich Christian W. 
Published: August 2003

AbstractFeedback systems with a single delay time—as described by delay‐differential equations—are known to exhibit various dynamical behaviors including complex oscillations and chaos. Here we show that the consideration of a broad distribution of delay times instead of a single delay results in a shift of the dynamical bifurcations toward higher parameter values, yielding a larger set of parameters with fixed point behavior or simple oscillatory behavior. We demonstrate similar phenomena in three different systems: neuronal feedback in the hippocampus, white blood cell production, i.e., the Mackey‐Glass equation, and population dynamics in theoretical ecology. Our results suggest that the observed simplification of the dynamics is independent of the shape of the delay distribution and the precise nature of the feedback. The existence of distributed delay times may yield a mechanism to avoid irregular fluctuations in biological feedback systems. © 2003 Wiley Periodicals, Inc.
Genetic distance in sequence space of evolving populations
Authors: Manffra Elisangela Ferretti , Kantz Holger , Ragwitz Mario 
Published: August 2003

AbstractA genome‐based measure for the distance between two populations is introduced. It fulfills the triangular inequality and can be easily computed, when the genetic sequences of a large number of individuals in two different populations are given. We use this distance for a study of mutating populations evolving under selective pressure, which are “living” on a computer. As a particular result, we find that evolution is diffusive. We include a comparison of our novel concept and the notion of genomic complexity of populations introduced by Adami et al. (Adami, C.; Ofria, C.; Collier, T.C. Evolution of biological complexity. Proc Natl Acad Sci USA 2000, 97, 4463–4468.) © 2003 Wiley Periodicals, Inc.
Prisoner's dilemma and public goods games in different geometries: Compulsory versus voluntary interactions
Authors: Hauert Christoph , Szabó György 
Published: August 2003

AbstractThe evolution of cooperation among unrelated individuals in human and animal societies remains a challenging issue across disciplines. In this context, two models have attracted most attention: the prisoner's dilemma for pairwise interactions and the public goods game for group interactions. The two games share many features as demonstrated by the close linkage of their cores. In spatially structured systems with individuals arranged on a lattice we investigate effects of group size and lattice geometry on the success of cooperators and defectors in compulsory and voluntary interactions. The geometry (square versus honeycomb), i.e., the connectivity turns out to have surprisingly pronounced and robust effects on the fate of cooperators. Apparently they thrive more easily on honeycomb lattices. As expected, it becomes increasingly difficult to promote cooperation in sizable groups but voluntary participation significantly lowers the threshold for persistent cooperative behavior. In fact, this effect is even more pronounced for larger groups. The risk avoiding option to not participate provides additional protection to clusters of cooperators against exploitation and introduces rock‐scissors‐paper‐type cyclic dominance, which gives rise to intriguing spatio‐temporal patterns. © 2003 Wiley Periodicals, Inc.
Adaptive online learning of generative stochastic models
Authors: Stiller J. C. 
Published: August 2003

AbstractIn online learning problems to choice of the learning rate, the weight given to new observations with respect to the knowledge gained from old ones, is a difficult problem. A novel algorithm for the adaptive, i.e., data‐dependent choice of the learning rate is presented. It is based on the idea of maximum likelihood estimation. In contrast to other approaches it does not rely on the stochastic independence of the observed data, the stationarity of the data source or a priori information about parameter changes. This makes it well suited for the analysis of ongoing nonstationary dynamic processes. It can be applied to the online learning of various different generative stochastic models. We present the adaptive online learning of Hidden Markov Models. © 2003 Wiley Periodicals, Inc.
Time‐domain analysis of conducting wire antennas and scatterers
Authors: Jung Baek Ho , Sarkar Tapan Kumar , Ji Zhong , Chung Young‐seek 
Published: August 2003

AbstractIn this work, a new method is presented for analyzing the transient electromagnetic response from conducting wire structures using the time‐domain integral equation (TDIE). Instead of the conventional marching‐on in time (MOT) technique, this solution method is based on Galerkin's method, which involves separate spatial and temporal testing procedures. Piecewise triangle basis functions have been used for spatial expansion and testing functions for arbitrarily shaped wire structures. The time‐domain variation is approximated by a temporal basis‐function set that is derived from the Laguerre functions. These basis functions are also used for temporal testing. The method presented in this paper results in very accurate and stable transient responses from wire antennas and scatterers. Representative numerical results are presented and compared with available data. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 433–436, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11082
Near‐field coupling between a printed antenna and a Fabry Perot resonator: Experimental study of the radiation properties at millimeter wave frequencies
Authors: Sauleau Ronan , Coquet Philippe , Matsui Toshiaki 
Published: August 2003

AbstractCompact focusing antennas, consisting of a Fabry–Perot (FP) cavity coupled to a printed source, are studied in the 60‐GHz band. Several configurations of antennas, including plane‐parallel or plano‐convex cavities excited by a patch antenna or an array, are considered and compared. In particular, their radiation characteristics are investigated experimentally as a function of the operating frequency and the thickness of the free‐space coupling region separating the primary radiator from the resonator. The optimum coupling conditions are also defined to maximize the efficiency and minimize the sidelobe level. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 438–443, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11084
Characteristic basis function method: A numerically efficient technique for analyzing microwave and RF circuits
Authors: Kwon Soon Jae , Du Kai , Mittra Raj 
Published: August 2003

AbstractIn this paper, we present an efficient electromagnetic analysis of planar microstrip structures, called the characteristic basis function method (CBFM). In this method, the original problem geometry is segmented into smaller regions called sections, and high‐level basis functions are generated to represent the electromagnetic characteristics of these sections. These basis functions are referred to as the characteristic basis functions (CBFs), and their use leads to a reduced matrix equation. Since the method only requires the solution of small‐size matrix equations, associated with isolated domains, the computational burden is relieved, and an acceleration of the solve time is achieved. The efficiency of this method is demonstrated via several examples, including a filter and an amplifier circuit. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 444–448, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11085
Wideband dipole arrays using non‐Foster coupling
Authors: Hansen R.C. 
Published: August 2003

AbstractA planar array of dipoles, with collinear dipoles connected by lumped negative inductances, is simulated by the piecewise sinusoidal method of moments. Over a multi‐octave bandwidth, the gain is close to the area gain, which is a remarkable result. The non‐Foster couplings smooth out and increase the current at low frequencies. Recent advances in transistor circuits and topology allow this new array to be considered. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 453–455, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11087
Slot antenna fed by a CPW line with tapered transition
Authors: Zheng Guiping , Kishk Ahmed A. , Glisson Allen W. , Yakovlev Alexander B. 
Published: August 2003

AbstractA tapered coplanar waveguide (CPW) transition is proposed in order to facilitate the connection between a slot antenna and coaxial connector. The broadband bow‐tie slot antenna is considered as an example in this design. The tapered transition is utilized to optimize the connection of two 50Ω CPW lines with different widths. A narrow CPW line is connected to the slot‐antenna feed point and the wide CPW line is connected to the coaxial SMA connector for measurement purposes. The tapered transition proposed here results in a negligible reflection in the CPW feed when its length is approximately λ/20. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 465–467, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11091
Polarization‐independent and electronically tunable Fabry Perot etalons with cross‐orthogonal liquid‐crystal layers
Authors: Lin Kuen‐Cherng , Chuang Wei‐Ching 
Published: August 2003

AbstractA novel structure of a polarization‐independent and electronically tunable Fabry–Perot interferometer is proposed. It consists of double layers of homogeneously aligned liquid‐crystal films with an orthogonal buffing direction. Both theoretical and experimental results show that a pure resonant wavelength with excellent polarization‐independent properties, was obtained. Our devices demonstrate power fluctuations of less than 0.5 dB and extinction ratios of up to 7 dB. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 475–477, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11093
Design of an isolated capacitor cell for three‐dimensional RF circuit integration
Authors: Kim Dae Jun , Lee Young Chul , Choi Byeong Gun , Eun Ki Chan , Park Chul Soon 
Published: August 2003

AbstractA compact multilayer capacitor cell isolated with perforated ground was designed and fabricated using low‐temperature ceramic co‐firing (LTCC) technology for three‐dimensional (3D) RF circuit application. The vertical transmission from any interferer placed 114 μm above the capacitor cell and the lateral transmission from any interferer 300 μm apart from the cell were controlled below −20 dB up to 15 GHz. The 2.8‐pF capacitor shielded with perforated ground of 600‐μm square edge and 800‐μm pitch revealed a self‐resonant frequency (SRF) of 7.6 GHz and Q factor of over 190 up to 3 GHz, which is an improvement of SRF by 0.8 GHz and Q factor by 224%, compared to the capacitor with a conventional blanket ground. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 484–486, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11096
Double Volterra series approach to FET mixers
Authors: Crespo‐Cadenas Carlos , Reina‐Tosina Javier 
Published: August 2003

AbstractA double Volterra series approach to analyze nonlinear microwave circuits is presented, with special emphasis on FET mixers. Considering a FET as a circuit with two input ports, a procedure to obtain closed‐form expressions for nonlinear transfer functions is presented. Based on this approach, the known time‐varying Volterra series technique can be demonstrated. Calculated conversion loss and two‐tone IMD for a FET‐resistive mixer are successfully compared with already published data. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 486–488, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11097
A simple approach towards the design and optimization of a C‐band injection‐locked amplifier
Authors: Chakravarty T. , Kumar Arun , Basu A. K. 
Published: August 2003

AbstractIn this paper, a simple design and optimization approach for a C‐band injection‐locked amplifier using a FET dielectric resonator oscillator is presented. Considerations such as frequency stability, mechanical tuning, repeatability, and low cost led to the choice of a dielectric resonator oscillator (DRO) as the injection‐locked amplifier (ILA). Here the heights of the DR and the spacer are experimentally optimized to obtain wider tunability (≈4.9%) with a power flatness of ±1 dB at power output levels of +30 dBm. The simplicity of the design approach is outlined and optimization technique discussed. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 488–491, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11098
A broadband microstrip antenna utilizing an integrated rectangular‐channel‐shaped feed
Authors: Bancroft Randy 
Published: August 2003

AbstractA broadband rectangular microstrip antenna, which utilizes a rectangular channel feed to obtain 25% impedance bandwidth, is described. A finite‐difference time‐domain (FDTD) analysis of the element's input impedance and radiation patterns versus measurement are presented. The FDTD impedance analysis utilizes a simplified coaxial probe feed. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 491–494, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11099