bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transient analysis and simulation of nonuniform lossy transmission lines
Authors: Bandurski Wojciech 
Published: July 2007

AbstractA new formulation of equations of the nonuniform lossy transmission line, in the form of integral equations based on the method of characteristics, has been introduced. Two methods of solution of these equations are presented, the first based on discretization of the integrals and, the second, a method of successive approximations, are presented and the results are compared. The presented integral equations of the line have interesting circuit representations and exhibit wave processes such as reflection, distortion, and attenuation. © 1992 John Wiley & Sons, Inc.
Application of singular value decomposition for integral equation procedures in MIMICAD
Authors: Thorburn Michael A. , Tripathi Vijai K. 
Published: July 2007

AbstractAn efficient moment method procedure which utilizes a point matching scheme together with a generalized inverse is formulated and implemented with the use of the singular value decomposition. The integral representation of Green's functions and a combination of semi‐infinite and subdomain expansion functions are used to formulate the numerical technique required to solve for the scattering parameters of planar microstrip multiports. Scattering parameters of typical microstrip discontinuities computed by utilizing this procedure are presented and compared with known published results. © 1992 John Wiley & Sons, Inc.
An efficient scheme for simulating large, passive microstrip layouts
Authors: Wu Doris I. 
Published: July 2007

AbstractAn efficient algorithm is presented here for simulating large, passive, microstrip layouts using a circle of influence approach with a full‐wave/integral‐equation‐based numerical solver. The procedure involves dividing the circuit into standard subcomponents or blocks and assigning a circle of influence for each block. Reiving on physical intuition, the computation of the couplings between blocks is then limited to those that fall within the circle. By adjusting the circle size, different orders of parasitic coupling can be included in the simulation process. Local junction effects from the individual blocks and the parasitic couplings between blocks that are in close physical proximity can always be taken into account. Aided by a newly developed graphical user interface, the tradeoff between computational efficiency and accuracy is examined by varying the diameter of the circle of influence. Data are presented to illustrate the effectiveness of this new approach. © 1992 John Wiley & Sons, Inc.
Numerical modeling of crossover and other junction discontinuities in two‐layer microstrip circuits
Authors: Hoorfar Ahmad , Zheng J. X. , Chang David C. 
Published: July 2007

AbstractA mixed‐potential, spatial‐domain integral equation approach is used to model the coupling and junction effects when microstrip structures in two different layers of a common substrate are crossing each other. A Galerkin method, together with the so‐called pseudo‐mesh current distribution for the basis functions, is then applied to accurately characterize multiport junctions. As an example, a four‐port crossover of two microstrip transmission lines is characterized in terms of the S‐parameters. © 1992 John Wiley & Sons, Inc.
Three‐dimensional electromagnetic analysis of shielded microstrip circuits
Authors: Hill A. , Burke J. , Kottapalli K. 
Published: July 2007

AbstractThe spectral domain integral equation approach is employed for the characterization of passive microstrip circuits that cannot be analyzed using the traditional lumped‐circuit‐based approach. General planar and certain three‐dimensional structures such as vias and air bridges are analyzed using the presented technique. Spurious mode coupling and the effect of the microwave housing on circuit performance are also investigated. © 1992 John Wiley & Sons, Inc.
A hybrid‐mode boundary integral equation method for normal‐ and superconducting transmission lines of arbitrary cross‐section
Authors: Schroeder Werner , Wolff Ingo 
Published: July 2007

AbstractA space domain Boundary Integral Equation (BIE) method for full‐wave analysis of general waveguide is presented. The method is demonstrated to be applicable to arbitrary shielded or unshielded waveguide cross‐sections ranging from optical waveguide to MMIC transmission lines. It allows for arbitrary isotropic complex media including normal (imperfect) conductors and superconductors as is demonstrated with full‐wave loss analysis of coplanar stripline and several thin‐film microstrip line configurations employing Au and YBCO conductors. An outline of the theory of the BIE method is given. The implications of nonsmooth boundary curves are considered, and special attention is given to the reliability of the method in being free of spurious solutions. © 1992 John Wiley & Sons, Inc.
Modeling of low‐noise microwave HEMTS for CAD‐oriented applications
Authors: Caddemi Alina , Sannino Mario 
Published: July 2007

AbstractThe simultaneous determination of noise, gain and scattering parameters through a computer‐driven noise figure measuring system allowed the rapid and accurate characterization of several samples of low noise HEMTs of the same family. From the measured parameters an equivalent circuit model representing the behavior of the typical device is extracted by means of a decomposition approach. Comparison between the model performance and the set of measured parameters of all devices are reported for the FHR 02FH (by Fujitsu). The modeling procedure is mainly oriented to the CAD of (M)MIC low noise wideband amplifiers. © 1993 John Wiley & Sons, Inc.
N‐way sectorial hybrid power divider design using boundary element method (invited article)
Authors: Miyazaki Moriyasu , Ishida Osami , Hashimoto Tsutomu 
Published: July 2007

AbstractA design method of an N‐way sectorial hybrid power divider is described, using the boundary element method (BEM). Scattering parameters and current density distribution on the sectorial part are obtained by BEM analysis. Isolation among output ports is much improved by putting a resistive slot in the sectorial part and resistive sheets between the adjacent output lines. The design method is verified by the six‐way power divider, which has been developed in our laboratory. © 1993 John Wiley & Sons, Inc.
Rectangular boundary division method and its applications (invited review article)
Authors: Nakajima Masayuki , Yamashita Eikichi 
Published: July 2007

AbstractThe rectangular boundary division method within the quasi‐TEM wave approximation is described as an analysis method to give basic parameters for designing complicated microwave transmission lines. Analysis procedures of some practical planar transmission lines are outlined and practical techniques for numerical computations with this method are discussed. © 1993 John Wiley & Sons, Inc.
Two‐dimensional analysis of cutoff frequencies of GaAs MESFETS with various substrate conditions (invited article)
Authors: Horio Kazushige 
Published: July 2007

AbstractCutoff frequencies of GaAs MESFETs are simulated by using a model that considers impurity compensation by deep levels in the semi‐insulating (SI) substrate. For a higher acceptor density SI substrate, an achievable cutoff frequency becomes higher because the substrate current becomes smaller. Effects of introducing a p‐buffer layer are also studied in terms of dependencies on p‐layer thickness and its doping density. © 1993 John Wiley & Sons, Inc.
Cylindrical gate approach for signal and noise modeling of striped channel field‐effect transistors (invited article)
Authors: Ando Yuji , Kuzuhara Masaaki , Itoh Tomohiro 
Published: July 2007

AbstractThe two‐dimensional charge‐control effect to dc and rf performances is studied for striped‐channel field‐effect transistors based on the cylindrical gate approximation. The present theory explains the transconductance enhancements as well as a flat noise figure dependence on the drain current, which have been experimentally observed for striped‐channel devices. © 1993 John Wiley & Sons. Inc.
Maskless device fabrication technology using an integrated microwave CAD/CAM system (invited article)
Authors: Yamada Takashi , Nogawa Kaoru , Nishikawa Madoka , Harada Yasoo 
Published: July 2007

AbstractA maskless process for MMICs using highly sensitive posi‐type EB resists was developed using our integrated microwave CAD/CAM system. The process can fabricate fine patterns with 0.1‐μm levels and align layer‐to‐layer and field‐to‐field within an accuracy below 0.05 μm (σ) using two types of alignment marks. Topography simulation of EB lithography using the Monte Carlo method was also added to the system to obtain the profiles of posi‐type single and double‐layer resist structures used for the process. The maskless process was successfully applied to an L‐band low‐noise amplifier with a 0.5‐μm gate length MESFET and reduced its TAT significantly. © 1993 John Wiley & Sons, Inc.
CAD formulas for resonant frequencies of TM01 and TM10 modes of rectangular patch antenna with superstrate
Authors: Chen Wei , Lee Kai‐Fong , Dahele Jash S. , Lee Richard Q. 
Published: July 2007

AbstractCurve‐fitting formulas based on moment method results are presented for the normalized resonant frequencies of the TM01 and TM10 modes of a rectangular patch antenna covered with a superstrate. The formulas can be used for a wide range of substrate and superstrate thicknesses and permittivities. Although they are obtained by fitting data points with aspect ratio a/b = 1.5, the formulas are found to be useful for a/b between 1.3 and 1.8. Comparison with measured data is given. © 1993 John Wiley & Sons. Inc.
Computer‐aided design of probe‐fed and aperture‐coupled rectangular microstrip antennas
Authors: Saed Mohammad A. 
Published: July 2007

AbstractThis article describes a method for analysis and design of rectangular microstrip antennas coupled to a microstrip feed line in a two‐layer configuration using either a probe or a small aperture. The technique is based on the cavity model and, thus is numerically efficient, making it suitable for computer‐aided design. The analysis takes into account higher order modes excited underneath the patch. Analysis results were implemented in two computer programs: an analysis program and a design program based on optimization techniques. Experimental results are presented to validate this method. © 1993 John Wiley & Sons, Inc.
A CAD‐oriented approach for aperture‐coupled patch antennas
Authors: Maci S. , Borselli L. , Avitabile G. , Gentili G. Biffi , Tiberio R. 
Published: July 2007

AbstractA simplified model is suggested for describing aperture‐coupled patch antennas in CAD applications. The scattering parameters of the antenna are calculated by assuming a single mode distribution for the currents on the slot and on the microstrip‐line. The coupling between the slot and the patch is represented by superimposing a contribution from a fundamental mode and that from higher order modes. The former is described by a complex eigenvalue of a cavity model with impedance walls. The latter is described by a parallel plate waveguide model, which properly accounts for the storage of reactive energy close to the slot. Numerical results are presented and compared with experiments. In particular, S‐band patches have been fabricated and tested to demonstrate the accuracy of the model. © 1993 John Wiley & Sons, Inc.
Numerical analysis of a crank‐type antenna on a dielectric substrate
Authors: Nakano Hisamatsu , Hirose Kazuhide 
Published: July 2007

AbstractCrank lines on a dielectric substrate backed by a conducting plane are designed for radiation of a circularly polarized wave. The guided wavelength of the crank lines is evaluated by an iterative technique based on the numerically determined current distribution. It is found that the crank lines designed with the final guided wavelength can radiate a circularly polarized main beam in the broadside direction. The frequency responses of the radiation characteristics are also presented.
Use of the FDTD method in the design of microstrip antenna arrays
Authors: Zimmerman Martin L. , Lee Richard Q. 
Published: July 2007

AbstractThe finite‐difference time‐domain (FDTD) method is a widely used numerical technique for computer‐aided design (CAD) of printed antennas and arrays. This technique can accurately predict performance characteristics of complex microstrip antennas, including the effects of parasitic elements and aperture‐coupled feeds. In the case of arrays, mutual coupling effects between closely packed elements can also be modeled. This article will examine the advantages and limitations of the FDTD method for CAD of microstrip arrays. Calculated results are compared with experiment for a 3‐patch coplanar parasitic patch array.
Analysis and CAD techniques for periodic leaky‐wave printed antennas: Numerical and experimental results
Authors: Encinar José A. 
Published: July 2007

AbstractTheoretical and experimental results are presented for a printed leaky‐wave antenna. Mode‐matching and EDC methods have been used to analyze the antenna and to design the prototypes. Reflection, transmission, and radiation measurements have been compared with theoretical predictions with good agreement. A CAD procedure is proposed to reduce the sidelobe level by tapering width and separation of metal strips.
Computer‐aided quasi‐static analysis of coplanar transmission lines for microwave integrated circuits using the finite difference method
Authors: Beker Benjamin , Cokkinides George J. 
Published: July 2007

AbstractThe finite difference method (FDM) is applied to the analysis of microwave integrated circuit (MIC) components that are based on the coplanar waveguide geometry. Effective dielectric constant, attenuation due to dielectric loss, and line impedance are calculated for open and shielded MICs as functions of transmission line dimensions and material parameters. The FDM is shown to be a practical engineering CAD tool for detailed examination of MICs having an arbitrary number of conductors and lossy dielectric layers, including field effect transistors.
Aging and overactive bladder may be associated with loss of urethral sensation in women
Authors: Kenton Kimberly , Lowenstein Lior , Simmons Jennifer , Brubaker Linda 
Published: July 2007

AbstractAimsTo compare current perception thresholds (CPT) in the urethra and bladder of women with idiopathic overactive bladder to asymptomatic controls.MethodsWomen with ≥1 urge urinary incontinence (UUI) episode per week on 7‐day diary, seeking treatment for UUI underwent CPT testing using a Neurometer® CPT device (Neurotron, Inc., Baltimore, MD). Testing was done in the urethra and bladder at three frequencies 2,000, 250, and 5 Hz corresponding to A‐β, A‐δ, and C fibers, respectively. CPT values from the women with UUI were compared to CPT values from a group of control women without lower urinary tract symptoms.ResultsForty‐eight controls without lower urinary tract symptoms and 13 women with UUI were included in the analysis. Women with UUI were significantly older (mean ± SD age 62 ± 14 and 44 ± 15,P < 0.0005) and more likely to be vaginally parous (P = 0.007) than control women. Urethral CPT at 2,000, 250, and 5 Hz were significantly higher in women with UUI than controls, while bladder CPT were not different between groups. Using logistic regression, to control for age and parity, urethral CPT at 5 Hz remained significantly higher in women with UUI than controls (P = 0.013).ConclusionUrethral sensation is significantly higher in older women, suggesting sensory neuropathy in the lower urinary tract increases with age and may contribute to the increase in overactive bladder seen with aging. These data reinforce the role of the urethra in lower urinary tract function. Neurourol. Urodynam. 26:981–984, 2007. © 2007 Wiley‐Liss, Inc.
The influence of N‐vinyl pyrrolidone on polymerization kinetics and thermo‐mechanical properties of crosslinked acrylate polymers
Authors: White Timothy J. , Liechty William B. , Guymon C. Allan 
Published: July 2007

AbstractPolymerization of multifunctional acrylate monomers generates crosslinked polymers that are noted for their mechanical strength, thermal stability, and chemical resistance. A common reactive diluent to photopolymerizable formulations is N‐vinyl pyrrolidone (NVP), which is known to reduce the inhibition of free radical photopolymerization by atmospheric oxygen. In this work, the copolymerization behavior of NVP was examined in acrylate monomers with two to five functional groups. At concentrations as low as 2 wt %, NVP increases the polymerization rate in copolymerization with multifunctional acrylate monomer. The relative rate enhancement associated with adding NVP increases dramatically as the number of acrylate double bonds changes from two to five. The influence of NVP on polymerization kinetics is related to synergistic cross‐propagation between NVP and acrylate monomer, which becomes increasingly favorable with diffusion limitations. This synergy extends bimolecular termination into higher double bond conversion through reaction diffusion controlled termination. Copolymerizing concentrations of 5–30 DB% NVP with diacrylate or pentaacrylate monomer also increases Young's modulus and the glass transition temperature (Tg) in comparison to neat acrylate polymers. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4062–4073, 2007
Particle Systems Characterization Using a Flat Cell Static Light Scattering Apparatus
Authors: Eliçabe Guillermo E. , Schroeder Walter F. , Frontini Gloria L. , Pettarin Valeria 
Published: July 2007

AbstractIn this work a light scattering apparatus for the study of heterogeneous liquid systems of evolving morphology is presented. A Fraunhofer configuration consisting of a linear array of photodiodes is used to detect the light scattered by thin samples illuminated by a He‐Ne laser light. Temperature control is available. The instrument is tested with the polymerization induced phase separation of a thermosetting polymer formulated with a divinylester resin copolymerized with styrene and modified with poly(methylmethacrylate). The system is successfully modeled as an arrangement of particles growing in size and number, and varying in composition. The ability of the experimental setup to provide results that can be quantitatively analyzed is checked using microspherical polystyrene standards. Different samples with nominal sizes of 0.5, 1 and 2 μm are used in different combinations of sample thickness and concentration. The analysis of the light scattering spectra is performed using inverse techniques to estimate the particle size distribution of the microspheres. The results agree with previous knowledge of the parameters of the samples.
The combination of antagonists of LHRH with antagonists of GHRH improves inhibition of androgen sensitive MDA‐PCa‐2b and LuCaP‐35 prostate cancers
Authors: Stangelberger Anton , Schally Andrew V. , Zarandi Marta , Heinrich Elmar , Groot Kate , Havt Alexandre , Kanashiro Celia A. , Varga Jozsef L. , Halmos Gabor 
Published: July 2007

AbstractBACKGROUNDAntagonists of growth hormone‐releasing hormone (GHRH) could extend the duration of response of androgen sensitive prostate cancers to androgen deprivation.METHODSWe investigated the effect of new GHRH antagonists MZ‐J‐7‐118 and MZ‐J‐7‐138 and luteinizing hormone‐releasing hormone (LHRH) antagonist Cetrorelix or castration on androgen sensitive MDA‐PCa‐2b and LuCaP‐35 prostate cancer models xenografted into nude mice. Animals bearing androgen‐independent LuCaP‐35V prostatic cancer model were also treated with MZ‐J‐7‐118.RESULTSReceptors for LHRH and GHRH were present in MDA‐PCA‐2b, LuCaP‐35, and LuCaP‐35V tumors. GHRH antagonists increased the inhibitory effect of surgical castration and LHRH antagonists on androgen sensitive MDA‐PCa‐2b and LuCaP‐35 tumors. The time to relapse of androgen‐dependent LuCaP‐35 tumors was extended by GHRH antagonists. Growth of androgen‐independent LuCaP‐35V xenografts was also significantly inhibited by MZ‐J‐7‐118. In MDA‐PCa‐2b tumors treatment with MZ‐J‐7‐118 caused a significant decrease of VEGF and Cetrorelix or its combination with MZ‐J‐7‐118 reduced EGF. The Bmax of EGF receptors was significantly reduced by Cetrorelix, MZ‐J‐7‐118 and their combination.CONCLUSIONSOur findings suggest that the use of a combination of antagonists of GHRH and LHRH could improve the therapy for androgen sensitive prostate cancer. Antagonists of GHRH could be also considered for treatment of androgen‐independent prostate cancers. Prostate 67: 1339–1353, 2007. © 2007 Wiley‐Liss, Inc.
Androgen‐dependent regulation of medium and long chain fatty acids uptake in prostate cancer
Authors: Pinthus Jehonathan H. , Lu Jian‐Ping , Bidaisee Laure A. , Lin Helen , Bryskine Inna , Gupta Radhey S. , Singh Gurmit 
Published: July 2007

AbstractBACKGROUNDEpidemiological and experimental studies suggest that both fatty acids and androgens have a role in the development and progression of prostate cancer (PC). Plasma membrane fatty acid binding protein (FABPpm) is a transporter of medium and long chain fatty acids (MCFA and LCFA) across the plasma membrane, and is identical to the mitochondrial protein aspartate aminotransferase (mAAT) that is regulated by testosterone only in prostate epithelial cells, a site where PC initially develops. We therefore hypothesized that FABPpm is also regulated by androgens.METHODSWe examined the effect of a synthetic androgen, R1881, and that of androgen receptor (AR) blocker, bicalutamide, on the expression of FABPpm and mAAT and on the uptake of fatty acids in the androgen‐sensitive LNCaP, androgen responsive 22rv1 and androgen‐independent CL1 human PC cells. This was done using immunofluorescence and confocal microscopy, Western blot, flow cytometry, and 3H‐oleate uptake studies.RESULTSAndrogen supplementation increased the cellular and surface expression of FABPpm and mAAT and increased the uptake of fluorescently labeled MCFA and LCFA and that of 3H‐oleate only in PC cells that express the AR. Bicalutamide inhibited this phenomenon.CONCLUSIONSThe uptake of MCFA and LCFA into PC cells is androgen regulated as well as the expression of FABPpm and mAAT. Prostate 67: 1330–1338, 2007. © 2007 Wiley‐Liss, Inc.