bluuebunny/crossref_metadata_2025 huggingface dataset:
Primary pediatric brain tumors
Authors: Wong Tai‐Tong , Ho Donald M. , Chang Kai‐Ping , Yen Sang‐Hue , Guo Wan‐You , Chang Feng‐Chi , Liang Muh‐Lii , Pan Hung‐Chi , Chung Wen‐Yuh
Published: October 2005

BACKGROUND

The purpose of the current study was to investigate a hospital series of 986 cases of primary pediatric brain tumors in Taiwan.

METHODS

The authors reviewed the database of primary pediatric brain tumors in patients < 18 years of age collected in Taipei Veterans General Hospital (Taipei VGH) from 1975 to May 2004. Age and gender distribution, location, and classification of brain tumors were analyzed. Intracranial tumors with diagnostic imaging were included. Nontumoral lesions, cysts, and vascular malformations were excluded.

RESULTS

The mean age of these 986 patients was 7.8 years, and the male to female ratio was 1.4:1. Supratentorial (including pineal–quadrigeminal) located tumors (58.3%) was predominant to infratentorial tumors (41.1%). In these series, 886 patients had either histologic diagnosis (842 patients) or clinical diagnosis (44 patients). The most common 5 categories of tumors were astrocytic tumors (31.1%), germ cell tumors (14.0%), medulloblastomas (13.3%), craniopharyngiomas (8.3%), and ependymal tumors (5.8%). Atypical teratoid/rhabdoid tumors (AT/RTs), a rare but highly malignant tumor, were 2.1%. The high incidence of primary intracranial germ cell tumors correlated with reported series from Japan and Korea. For the remaining 100 patients without diagnostic classifications, the majority were most likely astrocytic tumors in brain stem.

CONCLUSIONS

The authors analyzed a large hospital series of primary brain tumors in children. Both histologically verified and unverified tumors were recruited to avoid selective bias. Although it was not a study of a population‐based brain tumor registry, it could still be representative of primary pediatric brain tumors in Taiwan. Cancer 2005. © 2005 American Cancer Society.
Sexual functioning in patients with hepatocellular carcinoma
Authors: Steel Jennifer , Hess Stephanie A. , Tunke Laura , Chopra Kapil , Carr Brian I.
Published: October 2005

BACKGROUND

The objectives of the current study were to assess the rates of sexual dysfunction in patients with hepatocellular carcinoma (HCC) and compare the rates of sexual morbidity with a sample of patients diagnosed with chronic liver disease (CLD) and the general population. It was expected that patients diagnosed with HCC would have a greater prevalence of sexual dysfunction than those diagnosed with CLD and the general population, respectively. Furthermore, those patients who reported a sexual dysfunction would also have a poorer quality of life (QOL).

METHODS

Twenty‐one men diagnosed with HCC and 23 men diagnosed with CLD completed a battery of questionnaires that included the Sexual History Questionnaire and the Functional Assessment of Cancer Therapy‐Hepatobiliary.

RESULTS

Results indicated that 41% of patients reported a current sexual problem (29% of HCC patients and 71% of patients with CLD) and 43% met the Diagnostic and Statistical Manual of Mental Disorders–4th edition (DSM‐IV) criteria for at least 1 type of sexual dysfunction (25% of patients with HCC and 75% of patients with LD). Of the total sample, 68% reported being diagnosed with a comorbid medical condition or taking a medication that had potential sexual side effects. After eliminating cases with comorbid medical conditions and/or who were taking medications that contributed to sexual morbidity, the rate of sexual problems were found to be similar to that of the general population. Clinically significant differences were found with regard to the QOL. People who were experiencing sexual problems also reported a poorer QOL.

CONCLUSIONS

Although a large percentage of sexual dysfunction may have been secondary to comorbid medical problems and medications, treatment of the sexual dysfunction is still warranted. Cancer 2005. © 2005 American Cancer Society.
Prognostic factors for survival in patients with advanced renal cell carcinoma undergoing nonmyeloablative allogeneic stem cell transplantation
Authors: Peccatori Jacopo , Barkholt Lisbeth , Demirer Tanner , Sormani Maria Pia , Bruzzi Paolo , Ciceri Fabio , Zambelli Alberto , Da Prada Gian Antonio , Pedrazzoli Paolo , Siena Salvatore , Massenkeil Gero , Martino Rodrigo , Lenhoff Stig , Corradini Paolo , Rosti Giovanni , Ringden Olle , Bregni Marco , Niederwieser Dietger
Published: October 2005

BACKGROUND

The objective of this study was to identify prognostic factors for predicting survival in patients with advanced renal cell carcinoma (RCC) who had undergone an allogeneic stem cell transplantation after failure on immunotherapy.

METHODS

The authors studied 70 patients with advanced RCC who underwent allogeneic transplantation with a fludarabine‐based, reduced‐intensity regimen. Ten parameters were analyzed at the time of transplantation for their power to predict survival. Clinical features were examined first univariately; then, variables that were correlated significantly with survival in the univariate analysis were included in a multivariate Cox regression model.

RESULTS

Factors that were found to be associated significantly with limited survival were performance status, the number of metastatic sites, the presence of mediastinal metastasis, hemoglobin level, C‐reactive protein (CRP) level, lactate dehydrogenase (LDH) level, and neutrophil counts. All these variables were included in a multivariate Cox regression model, and three were retained in the final model. Patients were classified according to the score estimated by the final Cox model in two groups (above or below the median value): The median survival was 3.5 months for patients who had a poor prognosis patients versus 23 months for patients who had a good prognosis.

CONCLUSIONS

The current findings suggested that three easily available parameters (performance status, CRP level, and LDH level) could be used to stratify patients with advanced RCC who are candidates for allografting and to assist clinicians in decision‐making and selection of an appropriate treatment program. Cancer 2005. © 2005 American Cancer Society.
The contour integral method for loaded cracks
Authors: Pereira J. P. , Duarte C. A.
Published: October 2005

An extension of the contour integral method (CIM) for the computation of stress intensity factors for loaded cracks is presented. Numerical solutions of the two‐dimensional linear elasticity equations are computed with the p‐version of the generalized finite element method. Polynomial enrichment functions as well as enrichment with near crack tip asymptotic expansion are used. The robustness of the formulation with respect to the size of the extraction domain and the convergence of the computed stress intensity factors and energy release rate are analysed. Copyright © 2005 John Wiley & Sons, Ltd.
GCF: a general coupling framework
Authors: Ford R. W. , Riley G. D. , Bane M. K. , Armstrong C. W. , Freeman T. L.
Published: October 2005

Coupled modelling is increasingly necessary to make progress in understanding the science of complex physical phenomena and a number of bespoke (‘custom’) coupled solutions to specific scientific challenges have emerged in recent years. These coupled models generally consist of some framework code in which individual models are embedded. The framework code promotes the required interoperation of the models to solve the larger problem being addressed. Bespoke solutions limit the ability of scientists to share models and to couple them together flexibly to produce (efficient) implementations to address new problems. This paper presents an approach, GCF, which addresses several of these limitations. Individual model sharing and flexibility in composition and deployment is achieved by imposing some lightweight development rules for single models and capturing information relating to the models themselves, to their composition into coupled models and to their deployment onto computational resources as machine‐readable metadata. These metadata can be processed to support the generation of an implementation of the coupled model required by the developer. For example, lean and efficient framework code for the specific coupled model and deployment described by the developer can be generated. Alternatively, GCF‐compliant models can be automatically adapted for use within other, existing frameworks. This paper presents the design and implementation of a bespoke framework generator to achieve the former, and the flexibility in the composition of GCF‐compliant models is demonstrated. Copyright © 2005 John Wiley & Sons, Ltd.
The CCA component model for high‐performance scientific computing
Authors: Armstrong Rob , Kumfert Gary , McInnes Lois Curfman , Parker Steven , Allan Ben , Sottile Matt , Epperly Thomas , Dahlgren Tamara
Published: October 2005

The Common Component Architecture (CCA) is a component model for high‐performance computing, developed by a grass‐roots effort of computational scientists. Although the CCA is usable with CORBA‐like distributed‐object components, its main purpose is to set forth a component model for high‐performance, parallel computing. Traditional component models are not well suited for performance and massive parallelism. We outline the design pattern for the CCA component model, discuss our strategy for language interoperability, describe the development tools we provide, and walk through an illustrative example using these tools. Performance and scalability, which are distinguishing features of CCA components, affect choices throughout design and implementation. Copyright © 2005 John Wiley & Sons, Ltd.
Coupling climate models with the Earth System Modeling Framework and the Common Component Architecture
Authors: Zhou S. J.
Published: October 2005

Typical Earth system models involve coupled model components in high‐performance computing (HPC) environments. In the last few years, several frameworks have been developed for HPC applications. Two of them are component‐based frameworks: the Earth System Modeling Framework (ESMF) defining a component interface for Earth system models and the Common Component Architecture (CCA) defining a generic component model. The purpose of this work is to investigate the relationship between ESMF and CCA to deploy the best features of ESMF and CCA into a ESMF–CCA prototype and examine the prototype through a representative coupled climate model. Copyright © 2005 John Wiley & Sons, Ltd.
MpCCI—a tool for the simulation of coupled applications
Authors: Joppich W. , Kürschner M.
Published: October 2005

Many industrial and scientific applications are characterized by the interaction of different disciplines, such as fluid–structure interactions. For the individual disciplines sophisticated and validated solvers exist. This paper describes basic ideas, implementation details and application of MpCCI (mesh‐based parallel code coupling interface), a tool for the coupling of different simulation codes. Copyright © 2005 John Wiley & Sons, Ltd.
A Problem Solving Environment for interactive modelling of multiway data
Authors: van Stokkum Ivo H. M. , Bal Henri E.
Published: October 2005

A prototype Problem Solving Environment (PSE) is presented for problems in interactive modelling of multiway data. Multiway data result from measurements as a function of two or more independent variables. The PSE comprises a parameter estimation loop and a model adjustment loop. The model can be specified hierarchically using mathematically described building blocks which encapsulate the model assumptions. A typical case study of three‐way data illustrates the need for interactive model adjustment. Requirements for interactive problem solving are discussed. Copyright © 2005 John Wiley & Sons, Ltd.
Integration of two ocean models within Cactus
Authors: Dijkstra Fokke , van der Steen Aad J.
Published: October 2005

We describe our experiences with the integration of two ocean models (THCM and MOM4) within a computational framework, in this case Cactus. The use of a framework like Cactus offers many advantages to computational scientists. When integrating existing code some problems are still encountered. The main problems are structural ones caused by mismatches between data structures and parallelization models. We discuss these problems and try to offer directions for improvement of the available frameworks. Copyright © 2005 John Wiley & Sons, Ltd.
Impact of Structure and Morphology on Charge Transport in Semiconducting Oligomeric Thin‐Film Devices
Authors: Melzer Christian , Brinkmann Martin , Krasnikov Victor V. , Hadziioannou Georges
Published: October 2005

We investigated various thin‐film morphologies of vacuum‐deposited highly luminescent 2,5‐di‐n‐octyloxy‐1,4‐bis[4′‐(styryl)styryl]benzene (Ooct‐OPV5) in a typical light‐emitting‐diode device structure. Important modifications in the thin‐film morphology and structure were obtained by changing the substrate temperature in the range 23–90 °C. Structural analysis by X‐ray and electron diffraction provided clear evidence for polymorphism in evaporated thin films of Ooct‐OPV5. Concomitantly, the hole mobility in the corresponding devices was determined by transient electroluminescence measurements. We demonstrate that the substrate temperature Tsub is a key parameter that controls the hole mobility of the devices. Increasing Tsub between 23 and 84 °C results in a progressive increase of the zero‐field hole mobility from 10−6 to 10−4 cm2 V−1 s−1. The increase in hole mobility is correlated to the average grain size in the thin films. In addition, we give evidence for the existence of a peculiar growth mode in the bulk crystal structure of Ooct‐OPV5, whereby the (a,b) and (b,c) planes can grow in a homoepitaxial manner.
Influence of Molecular Order on the Local Work Function of Nanographene Architectures: A Kelvin‐Probe Force Microscopy Study
Authors: Palermo Vincenzo , Palma Matteo , Tomović Željko , Watson Mark D. , Friedlein Rainer , Müllen Klaus , Samorì Paolo
Published: October 2005

We report a Kelvin‐probe force microscopy (KPFM) investigation on the structural and electronic properties of different submicron‐scale supramolecular architectures of a synthetic nanographene, including extended layers, percolated networks and broken patterns grown from solutions at surfaces. This study made it possible to determine the local work function (WF) of the differentπ‐conjugated nanostructures adsorbed on mica with a resolution below 10 nm and 0.05 eV. It revealed that the WF strongly depends on the local molecular order at the surface, in particular on the delocalization of electrons in theπ‐states, on the molecular orientation at surfaces, on the molecular packing density, on the presence of defects in the film and on the different conformations of the aliphatic peripheral chains that might cover the conjugated core. These results were confirmed by comparing the KPFM‐estimated local WF of layers supported on mica, where the molecules are preferentially packed edge‐on on the substrate, with the ultraviolet photoelectron spectroscopy microscopically measured WF of layers adsorbed on graphite, where the molecules should tend to assemble face‐on at the surface. It appears that local WF studies are of paramount importance for understanding the electronic properties of active organic nanostructures, being therefore fundamental for the building of high‐performance organic electronic devices, including field‐effect transistors, light‐emitting diodes and solar cells.
Direct Measurement of the End‐to‐End Distance of Individual Polyfluorene Polymer Chains
Authors: Muls Benoît , Uji‐i Hiroshi , Melnikov Sergey , Moussa Alain , Verheijen Wendy , Soumillion Jean‐Philippe , Josemon Jacob , Müllen Klaus , Hofkens Johan
Published: October 2005

Wide‐field imaging of individual multichromophoric molecules and successive photobleaching were used to determine, accurately, the relative position of the chromophores in such systems. First, a polyphenylene dendrimer with well‐defined geometry was used to establish the accuracy in localization that can be obtained by this methodology. For a signal‐to‐noise ratio of 20, interchromophoric distances could be measured with 4 nm accuracy. Next, the method was used to determine the end‐to‐end distribution of an end‐capped polyfluorene polymer. From comparison between the experimental and simulated distributions, information on the conformation of the polymer could be deduced. It was found that the polymer has a nonlinear conformation. A conjugation length of six monomer units gave the best fit of the experimental data to the proposed model.
Flow cytometric analysis of tracheary element differentiation in Zinnia elegans cells
Authors: Weir Iona E. , Maddumage Ratnasiri , Allan Andrew C. , Ferguson Ian B.
Published: October 2005

Background

Tracheary element (TE) differentiation in single cells in culture isolated from Zinnia elegans leaves involves programmed cell death (PCD) co‐ordinated with key morphological developments. We have used flow cytometry to analyze physiological and nuclear changes in the differentiating cells. Flow cytometry allows the identification of subpopulations, thereby removing the obscuring effect of population heterogeneity that occurs with the use of other techniques.

Methods

Cell viability, plasma membrane integrity, oxidative activity, intracellular calcium and pH, cell wall thickening, the possible role of microtubule rearrangement, chromatin condensation, and DNA breakdown were followed by flow cytometry from the first stages of TE induction.

Results

TE differentiation could be enhanced and made more synchronous by a centrifugation step at 72 h after cell isolation. Size and shape changes were the first changes identified in differentiating cells, and these properties could be used to isolate differentiating populations by back‐gating. Chromatin condensation and nDNA breakdown followed patterns characteristic of programmed cell death.

Conclusions

We have used flow cytometry to characterize the morphological and physiological changes that occur during TE differentiation, and our findings indicate that this process is a form of autophagic PCD in which microtubule rearrangement appears to play a role. © 2005 Wiley‐Liss, Inc.
Evaluation of error rate performance for ODS code‐spread system using simulations
Authors: Naik Ameya K. , Tamhankar Meenal M. , Sinha Mahesh P.
Published: October 2005

Code‐spread and conventional CDMA systems are discussed and compared for varying interleaver sizes. Results are evaluated in terms of BER versusEb/No. It is observed that the code‐spread systems give better performance. It is also observed that performance of both the systems improves significantly with an increase in the interleaver size. Copyright © 2005 John Wiley & Sons, Ltd.
Phonological processing skills as predictors of literacy amongst Arabic speaking Bahraini children
Authors: Mannai Haya al , Everatt John
Published: October 2005

This paper reports a study of the reading and spelling skills of grades 1–3 Arabic‐speaking children in Bahrain. Children were tested on their literacy skills (single word reading and spelling), their ability to decode letter strings (non‐word reading) and measures of phonological awareness, short‐term memory, speed of processing and non‐verbal ability. These tests were included to identify the best predictors of literacy skills amongst Arabic young readers. The results were consistent with the literature based on tests of English‐speaking children in that measures of phonological skills (decoding and awareness) were the best predictors of variability in reading and spelling among the Bahraini children. The results are discussed in terms of the literacy experiences of the children and the use of short vowels in Arabic writing. Copyright © 2005 John Wiley & Sons, Ltd.
A method of multifractal traffic generation with appropriate short‐term distribution using nonlinear filtering
Authors: Shimizu Junya
Published: October 2005

This paper proposes a method of generating network traffic patterns needed in stress testing of Web sites. This method mainly consists of two stages: in the first stage, from a positive root signal, a signal pattern with multifractality and a long‐tail distribution is synthesized using wavelets. In the second stage, the short‐term distribution characteristics of the pattern generated at the first stage are adjusted by decomposition into low‐frequency and high‐frequency components by nonlinear filtering and changing the ratios of their two components in order to obtain the appropriate short‐term distribution, so as to finally obtain network traffic that also has an appropriate long‐range dependence. Simulation results are also presented for validation of this proposed method. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 89(2): 47–56, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20223
Investigation on suppression effect of radiated electromagnetic field from printed circuit board with differential transmission mode using method of moments
Authors: Matsubara Ryo , Miyauchi Keiji , Ishida Yasuhiro , Tokuda Masamitsu , Kuwabara Nobuo
Published: October 2005

As the frequency used in electronic devices increases, limitations on the lumped element type components for prevention of radiated emission appear. Methods for suppression of radiated emission from printed circuit boards by means of differential mode transmission have been studied. However, most of these studies are centered on theoretical analysis. There has been no investigation from both the experimental and theoretical points of view in the high‐frequency regions. In this paper, with a view to easily deriving the suppression effect of radiated emission, the electromagnetic fields radiated from differential mode transmission and common mode transmission are derived by the method of moments from a model of parallel micro‐strip lines with the effective relative permittivity and the equivalent wires. The suppression of radiation from the differential mode transmission is studied in comparison with the measured data. It is found that the difference between the measured and calculated values of the maximum radiated electric field is less than about 3 dB in the range of 100 MHz to 3 GHz, except near 2 GHz in the case of the common mode transmission. With regard to the suppression effect, the difference between the measured and calculated values is less than 5 dB at 1 to 3 GHz. An investigation with this analytical model found that the radiation suppression effect can be improved by 5 to 10 dB at 1 to 3 GHz by changing the spacing between parallel microstrip lines to 1 mm from 5 mm, that the suppression effect is degraded by about 5 dB due to curvature, and that the radiation suppression effect is decreased by 5 to 20 dB at 1 to 3 GHz if the deviation of the transmission line lengths of a pair of parallel microstrip lines measured from one end reaches 10%. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 89(2): 36–46, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20227
An equivalent weight vector model of array antennas considering current distribution along dipole elements
Authors: Iigusa Kyouichi , Ohira Takashi , Komiyama Bokuji
Published: October 2005

In this paper, we show that the current distribution along the parasitic dipole elements loaded by variable reactors varies greatly depending on the variable reactor value. Thus, when the directionality of an Electronically Steerable Passive Array Radiator (ESPAR) antenna constructed from parasitic dipoles is calculated, we must consider the changes in the current distribution along these elements. Therefore, we propose a method where the current weight is the value of the vector effective length of each element multiplied by the current value at the port. We also show that when the dipole length is less than approximately the half wavelength, the vector effective length is calculated for the most part by the ratio of the port voltage to the port current. From this relationship, even if the current distribution along an element is not determined, the vector effective length of a parasitic element can be calculated from the value of the variable reactor loading the element. Thus, the current distribution along the elements can be easily considered when calculating the directionality of the ESPAR antenna. We present a method that calculates the directionality of the feed dipole array antenna having mutual coupling among the elements that considers the current distribution along the element where not only the port current but also the port voltage are set as the weights. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 89(2): 22–35, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20232
Multibits/sequence optical code division multiple access system applying bit erasure correction by differential encoding
Authors: Miyazawa Takaya , Ono Tomoyuki , Sasase Iwao
Published: October 2005

In this paper, we propose a Multibits/Sequence Period Optical Code‐Division Multiple‐Access (MS‐OCDMA) system applying bit erasure correction by differential encoding. In the proposed system, the present transmitted shifted code pattern is determined on the basis of the previous and the present transmitted bits. In the receiver, threshold detection is applied to the avalanche photodiode (APD) output in each shifted code pattern. When the number of APD outputs exceeding the threshold level is either more than two or zero, the present received bit is judged to be an erasure. Then, the present received bit is estimated by the information about the shifted code patterns for which the APD outputs exceed the threshold and the nonerasure bits before or after the present erasure bit, and the erasure bit is corrected. In addition, the proposed system can correct a received bit sequence as an erasure bit instead of an error bit. We analyze the bit error rate (BER) of the proposed system and show that the proposed system has a better BER than the MS‐OCDMA system with Reed‐Solomon (RS) codes at the same bit rate and with the same number of subscribers. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 89(2): 1–11, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20252
Proposal and examination of new type of TFT with tunneling dielectric film at both ends of channel fabrication area
Authors: Matsuo Naoto , Kihara Hiroyuki , Yamamoto Akinori , Kawamoto Naoya , Hamada Hiroki
Published: October 2005

An important aspect of a thin‐film transistor (TFT) is reducing the current flowing between the source and drain when the gate is off. In this research, we proposed a new TFT, the tunneling dielectric TFT (TDTFT), that has a thin dielectric film on both ends of the channel region, and studied its operation through simulations. We calculated the drain current (Ioff) when the gate is off, the drain current–drain voltage characteristic, and the transconductance in the TDTFT. When the thin dielectric film is a 0.5‐nm‐thick TiO2 film, Ioff of the TDTFT is about six digits less than that of a conventional TFT. We also studied the double silicon on insulator (DSOI) structure which improves the drive power of the TFT even for a thin Si film. When a TDTFT is fabricated on DSOI, simple calculations showed that the on–off ratio was several times better than that of a conventional TFT. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 88(11): 44–53, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.10210
A novel design technique of NRD guide bend
Authors: Sawada Hirokazu , Yoneyama Tsukasa , Kuroki Futoshi
Published: October 2005

In NRD guide circuit technologies, 90° and 180° bends are often used. However, due to the generation of unwanted parasitic modes, the radius of curvature of an optimum bend can take only discrete values, and this limitation has been a bottleneck for the design of NRD guide circuits. In order to resolve this problem, the theory of NRD guide bends has been reconsidered. It has been found that the radius of curvature of the bend can be designed arbitrarily if the phase‐constant difference (Δβ) between the unwanted LSE mode and the operating LSM mode is made variable. In this paper, as a way to make Δβ variable, the placement of a metal rod or a ring in close proximity to the bend is studied. The investigation results in a new kind of NRD guide bend. Since the transmission characteristics are degraded by a small air gap between the dielectric and metal, a method is proposed for improvement of the characteristics by filling the gap with dry‐hardening liquid dielectric materials (such as enamel). © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 88(11): 37–43, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20114
Design methodology of BPF using LC tap‐coupling λ/4 resonators and location control of attenuation poles
Authors: Kamiyama Tomohide , Wada Kouji , Hashimoto Osamu
Published: October 2005

In this paper, we focused on the resonance characteristic of the LC tap‐coupling λ/4 resonator, which can locate the attenuation poles on both sides near the fundamental resonance frequency (fr), and examined the design of the bandpass filter (BPF) using this resonator and the location control of the attenuation poles. From this result, although the number of elements increased somewhat over a conventional loaded‐element tap‐coupling resonator BPF, we theoretically showed that independent control of the placement locations of the attenuation poles appearing near the passband was possible, and the added value was large. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 88(11): 21–27, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20165
Loss reduction of photonic crystal waveguide fabricated by the autocloning technology
Authors: Miura Kenta , Ohtera Yasuo , Ohkubo Hiroyuki , Sato Takashi , Akutsu Naoto , Hikage Masahiro , Ishino Naoto , Kawashima Takayuki , Kawakami Shojiro
Published: October 2005

The heterostructured photonic crystal waveguide fabricated by the autocloning technology allows fabrication jointly with other functional devices. Hence, this approach is useful for elemental components for the next‐generation high‐function planar optical circuits. When this waveguide is used for interconnection of optical circuits, its propagation loss should be as small as possible. In this investigation, Ta2O5/SiO2 is selected as the construction material. Further, by using a waveguide configuration minimizing the scattering loss, substantial loss reduction was achieved. It is especially effective to use a simple flat multilayered film structure. A loss reduction up to a propagation loss of 0.1 dB/mm was realized. The present waveguide has a small coupling loss of 0.43 dB with an existing optical fiber (a high‐Δ fiber with a mode field diameter of 2.7 µm) and hence is easily adapted to the optical communication system. The heterostructured photonic crystal waveguide is thus extremely practical. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 88(11): 10–20, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20195
Kinetic study of quasi‐ballistic electron transport in nanoscale semiconductor devices
Authors: Sano Nobuyuki
Published: October 2005

We studied the effect of the scattering accompanying dispersion in quasi‐ballistic transport at room temperature in nanoscale semiconductor devices primarily by using numerical calculations. The electron velocity distribution function based on a simple n+‐n‐n+ structure was directly determined by solving the semiclassical Boltzmann transport equation. We discovered that the velocity distribution function of electrons near the potential barrier obtained from the Boltzmann transport equation differs from the function assuming ballistic transport and always has a negative velocity component due to scattering in the channel region that cannot be ignored. This analysis result means that the scattering effect in the channel region cannot be ignored even for nanoscale elements. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 88(11): 1–9, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20196
Improvement of identification algorithms in the freehand curve identifier FSCI
Authors: Takikawa Hiroyasu , Yasufuku Naofumi , Saga Sato
Published: October 2005

We already proposed the freehand curve identifier FSCI, based on fuzzy theory, as a freehand figure recognition engine. We next investigated the improvement of the recognition rate of FSCI by learning optimization of parameters. This paper proposes improvements of the FSCI algorithm itself, namely, improvement of the hypothetical fuzzy model formulation, and introduction of necessity into the fuzzy inference rules. It was shown by experiments that these improvements have effects which cannot be obtained by conventional parameter adjustment. © 2005 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 88(11): 54–63, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20224
Rotation invariant image matching by interpolated eight‐direction block matching
Authors: Hayashi Hiroki , Saitoh Fumihiko
Published: October 2005

Template image matching is a method for seeking a target image area that is similar to a registered template image. However, template matching is a general‐purpose technique for various image applications, and the image under consideration must generally have the right position with respect to the template image. Therefore, the computational cost is large when both the location and inclination of the target image area are unknown. This paper proposes a method of searching for a target image area with arbitrary location and inclination by multiple matching using separated block template images. In the method, the template image is divided into small block areas with a size of 3 × 3 pixels. The image pattern in each block is rotated by 45° and matching is performed between the rotated blocks and the image under consideration. The experimental results show that the proposed method has higher matching reliability than the conventional methods. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 154(1): 66–73, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20107
Distinctive flow properties of liquid jet generated by EHD pump and conical nozzle
Authors: Hanaoka Ryoichi , Nakamichi Hiroyuki , Takata Shinzo , Fukami Tadashi
Published: October 2005

The electrohydrodynamic liquid jets induced by the mechanism which is referred to as pure conduction pumping were investigated in isothermal weakly conducting liquids, HFC43‐10 and HCFC123. The properties of the liquid jets (flow velocity, pumping pressure, and flow pattern) were examined by using grounded electrodes of four different types opposite a pseudo‐doughnut electrode under an applied DC voltage. These electrode systems gave rise to a powerful liquid jet, but in the working liquids used here, there was an effect of the voltage polarity on the flow direction. In order to create a more effective liquid jet with high directivity, a special nozzle (referred to as a conical nozzle in this paper) was used together with the electrode system. This nozzle can produce a distinctive pattern (spiral structure) of jets emerging from the outlet of the nozzle. In this paper, the spiral structure of the liquid jets has been analyzed using the basic equations of fluid mechanics. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 154(1): 9–19, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20133
Multitrajectory dynamic tunneling algorithm for global optimization
Authors: Yasuda Keiichiro , Kanazawa Takahiko
Published: October 2005

Most of the actual optimization problems are large‐scale, nonlinear, and multipeaked (nonconvex). Furthermore, with the widespread use of high‐speed and large‐capacity computers as the background, it is felt necessary in recent years to derive a global solution for nonlinear and multipeaked optimization problems. It is one of the most important topics in optimization. This paper proposes a new dynamic tunneling algorithm with multitrajectories (Multitrajectory Dynamic Tunneling Algorithm) that is composed of two systems, an optimization system and a tunneling system. The numerical stability of the conventional dynamic tunneling algorithm is theoretically investigated and interaction between each trajectory of the tunneling system is introduced in order to improve search efficiency. The proposed algorithm is applied to 2‐variable and 10‐variable typical multipeaked nonlinear optimization problems. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 154(1): 47–58, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20171
Feature extraction of AR as a performance index for load frequency controls of interconnected power systems
Authors: Yorino Naoto , Zoka Yoshifumi , Nakanishi Koichi , Nakagawara Satohiko , Kamei Yoshifumi , Sasaki Hiroshi
Published: October 2005

Recently, the evaluation of control performances of interconnected power systems has become an important issue with respect to individual load frequency controls. Several performance measures are in practical use such as Area Control Error (ACE), Mutual Aid Criterion (MAC), and Control Performance Standard (CPS). Area Requirement (AR) is an alternative expression for ACE, where AR=−ACE. However, the characteristics of these indices have not been sufficiently studied as far as the authors know. In particular, this is the case for their dynamic behavior against random load disturbances. This paper investigates the performance index, AR, through analysis of two‐area systems. Major dynamic elements of interconnected systems affecting the frequency are taken into account to investigate responses of the system against load disturbances. The analysis shows that, when new systems are interconnected, the smaller system tends to require more effort of control against load disturbances to keep the same value of the performance indices. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 154(1): 20–28, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20233
Synthesis, Characterization, and Reactivity of Neutral and Cationic Pd–C,N,N Pincer Complexes
Authors: Bianchini Claudio , Lenoble Géraldine , Oberhauser Werner , Parisel Sébastien , Zanobini Fabrizio
Published: October 2005

The ortho‐palladation of the iminophosphane ligand 6‐phenyl‐2‐[(2,6‐diisopropylphenyl)imino]pyridine (HL) with Pd(OAc)2 and PdCl2(PhCN)2 in benzene yields the neutral Pd–C,N,N pincer complexes Pd(OAc)(κ3‐C,N,N‐L) (1) and PdCl(κ3‐C,N,N‐L) (2), respectively. In the presence of NaBAr′4 [Ar′ = 3,5‐(CF3)2C6H3], 2 reacts in CH2Cl2 with MeCN, PPh3, or PH[o‐MeO(C6H4)]2 to give the cationic palladium(II) pincer complexes [Pd(CH3CN)(κ3‐C,N,N‐L)]BAr′4 (3), [Pd(PPh3)(κ3‐C,N,N‐L)]BAr′4 (4) and {Pd[PH(o‐MeOC6H4)2](κ3‐C,N,N‐L)}BAr′4 (5), respectively. Complexes 1–5 have been characterized by multinuclear NMR and IR spectroscopy. The solid‐state structures of 1 and 2 have been determined by single‐crystal X‐ray diffraction techniques. Both the neutral compounds 1 and 2 and the cationic derivatives 3, 4, and 5 were tested as catalyst precursors for the Suzuki cross‐coupling of 4‐bromo‐ and 4‐chloroacetophenone with phenylboronic acid. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Crystal Structure and Magnetic Behaviour of the New Gadolinium Complex Compound Gd2(ClH2CCOO)6(bipy)2
Authors: John Daniela , Urland Werner
Published: October 2005

Single crystals of the title compound have been obtained by reaction of Gd3(ClH2CCOO)9(H2O)5 with 2,2′‐bipyridyl (bipy) in a solution of ethanol and water. Gd2(ClH2CCOO)6(bipy)2 crystallises in the triclinic space group P$\bar {1}$ (Z = 2) with a = 959.5(3) pm, b = 980.9(3) pm, c = 1163.9(4) pm, α = 68.67(3) °, β = 84.82(4)° and γ = 82.47(4)°. The crystal structure is built up of discrete molecules of dinuclear Gd3+–Gd3+ units. The corresponding residual (all data) for the refined structure is 4.46 %. The magnetic behaviour of the compound was investigated in the temperature range of 1.76–300 K. The magnetic data were interpreted considering exchange interactions within the dimeric unit (Jex = –0.020 cm–1). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
The Osher scheme for non‐equilibrium reacting flows
Authors: Suresh Ambady , Liou Meng‐Sing
Published: October 2005

An extension of the Osher upwind scheme to non‐equilibrium reacting flows is presented, Owing to the presence of source terms, the Riemann problem is no longer self‐similar and therefore its approximate solution becomes tedious. With simplicity in mind, a linearized approach which avoids an iterative solution is used to define the intermediate states and sonic points. The source terms are treated explicitly. Numerical computations are presented to demonstrate the feasibility, efficiency and accuracy of the proposed method. The test problems include a ZND (Zeldovich‐Neumann‐Doring) detonation problem for which spurious numerical solutions which propagate at mesh speed have been observed on coarse grids. With the present method, a change of limiter causes the solution to change from the physically correct CJ detonation solution to the spurious weak detonation solution.
Prediction of turbulent offset jet flows with an assessment of QUICKER scheme
Authors: Koo Hyeong‐Mo , Park Seung O.
Published: October 2005

The QUICKER scheme extended for non‐uniform rectangular grid systems has been applied to predict the turbulent offset jet flows. Computational results obtained with the QUICKER scheme are compared with those from the skew‐upwind and the hybrid schemes. Computational results include the reattachment length, the velocity profile, the axial velocity decay curve, and the shear stress distribution. In the sense of an overall agreement with the experimental data, the QUICKER scheme is found to be superior to the other two schemes. Boundary conditions are carefully set up to account for various flow conditions. Special attention has been given to the set‐up of entrainment boundary condition. It is emphasized that the numerical diffusion due to streamline‐to‐grid skewness far exceeds the turbulent diffusion in offset jet flows; therefore, a numerical scheme that would minimize the numerical diffusion is a prerequisite for a better prediction of the turbulent offset jet flows.
Integral transform solution for the lid‐driven cavity flow problem in streamfunction‐only formulation
Authors: Guerrero J. S. Pérez , Cotta R. M.
Published: October 2005

The basic ideas in the generalized integral transform technique are further advanced to allow for the hybrid numerical‐analytical solution of the two‐dimensional steady Navier‐Stokes equations in streamfunction‐only formulation. The classical lid‐driven square cavity problem is selected for illustration of the approach. The corresponding biharmonic‐type non‐linear partial differential equation for the streamfunction is integral transformed in one of the co‐ordinates and an infinite system of coupled non‐linear ODEs for the transformed potential results in the other independent variable. Upon truncation to an appropriate finite order, the ODE system is numerically solved by well‐established algorithms with automatic error control devices. The convergence behaviour of the eigenfunction expansion is demonstrated and reference results are provided for typical values of Reynolds number.
A stable high‐order method for the heated cavity problem
Authors: Choo Joshua Y. , Schultz D. H.
Published: October 2005

A fourth‐order method, without using extrapolation, is developed for the steady‐state solution of a non‐linear system of three simultaneous partial differential equations for the flow of a fluid in a heated closed cavity. The method is a finite difference method which has converged for all Rayleigh numbers Ra of physical interest and all Prandtl numbers Pr attempted. The results are presented and compared with some of the accurate results available in de Vahl Davis and Jones, Shay and Schultz, and Dennis and Hudson. The method used to develop the fourth‐order method presented in this paper can be used to develop high‐order methods for other partial differential equations. The method was developed to be stable without using the upwinding technique.
A global approach to error estimation and physical diagnostics in multidimensional computational fluid dynamics
Authors: Haworth D. C. , El Tahry S. H. , Huebler M. S.
Published: October 2005

An approach for simultaneously assessing numerical accuracy and extracting physical information from multidimensional calculations of complex (engineering) flows is proposed and demonstrated. The method is based on global balance equations, i.e. volume‐integrated partial differential equations for primary or derived physical quantities of interest. Balances can be applied to the full computational domain or to any subdomain down to the single‐cell level. Applications to in‐cylinder flows in reciprocating engines are used for illustration. It is demonstrated that comparison of the relative magnitude of the terms in the balances provides insight into the physics of the flow being computed. Moreover, for quantities that are not conserved at the cell or control volume level in the construction of the numerical scheme, the imbalance allows a direct assessment of numerical accuracy in a single run using a single mesh. The mean kinetic energy imbalance is shown to be a particularly sensitive indicator of numerical accuracy. This simple and powerful diagnostic approach can be implemented for finite‐difference, finite‐volume or finite‐element methods.
Linear stability of swirling flows computed as solutions to the quasi‐cylindrical equations of motion
Authors: Spall Robert E.
Published: October 2005

The linear stability of numerical solutions to the quasi‐cylindrical equations of motion for swirling flows is investigated. Initial conditions are derived from Batchelor's similarity solution for a trailing line vortex. The stability calculations are performed using a second‐order‐accurate finite‐difference scheme on a staggered grid, with the accuracy of the computed eigenvalues enhanced through Richardson extrapolation. The streamwise development of both viscous and inviscid instability modes is presented. The possible relationship to vortex breakdown is discussed.
Multilevel methods for temporal and spatial flow transition simulation in a rough channel
Authors: Liu Zhining , Liu Zhixing , Liu Chaoqun , McCormick Steve
Published: October 2005

We investigate the instability of 2D incompressible flows in a rough planar channel by tracking the growth of the unstable mode in its early stage. We develop both second‐ and fourth‐order finite difference methods on a staggered grid, together with a fully implicit time‐marching scheme, using grid generation to accommodate fairly general geometries. A multigrid full approximation scheme based on the line‐distributive relaxation method is used for fast convergence. For a 2D smooth channel, numerical results show good agreement with the analytic solution obtained from linear theory for small disturbances. Numerical results for a 2D channel with one and two roughness elements are analysed by Fourier analysis. They show how the roughness elements affect the growth of the perturbation.