bluuebunny/crossref_metadata_2025_split huggingface dataset:
Infinite dimensional exponential attractors for a non–autonomous reaction–diffusion system
Authors: Efendiev Messoud , Miranville Alain , Zelik Sergey 
Published: January 2003

AbstractIn this article, we give a construction of exponential attractors that is valid for general translation–compact non–autonomous systems. Since they are generally infinite dimensional, we replace, compared with the standard definition, the condition of finite fractal dimensionality of exponential attractors by requiring that their epsilon–entropy have the same form as that of the uniform attractor. As an example, we prove the existence of an (infinite dimensional) exponential attractor for a reaction–diffusion system.
The cohomology of Banach space bundles over 1–convex manifolds is not always Hausdorff
Authors: Erat Matjaž 
Published: January 2003

AbstractA holomorphic Hilbert space bundle E over ℙ1 is constructed such that H1(ℙ1, E) is not Hausdorff. Lifting this bundle to 𝒪 (–1) it is shown that such bundles exist also on non–compact 1–convex spaces.
Exact packing measure of linear Cantor sets
Authors: Feng De–Jun 
Published: January 2003

AbstractLet K be the attractor of a linear iterated function system Sjx = ρjx +bj (j = 1, …, m) on the real line satisfying the open set condition (where the open set is an interval). It is well known that the packing dimension of K is equal to α, the unique positive solution y of the equation $ \sum _{j = 1} ^m \rho ^y _{j = 1} $; and the α–dimensional packing measure 𝒫α(K) is finite and positive. Denote by μ the unique self–similar measure for the IFS $ \{ S _j \} ^m _{j=1} $ with the probability weight $ \{ \rho ^\alpha _j \} ^m _{j=1} $. In this paper, we prove that 𝒫α(K) is equal to the reciprocal of the so–called “minimal centered density” of μ, and this yields an explicit formula of 𝒫α(K) in terms of the parameters ρj, bj (j = 1, …, m). Our result implies that 𝒫α(K) depends continuously on the parameters whenever $ \sum _j \rho_j < 1 $.
On the boundedness of the mapping f ↦ |f|μ, μ > 1 on Besov spaces
Authors: Kateb Djalil 
Published: January 2003

AbstractGiven μ > 1, 1 ≤ p≤¡∞, 1 ≤ q ≤ ∞, and 0 < s < μ + $ 1 \over p $, we show that the mapping Fμ : f ↦ |f|μ maps the Besov pace Bsp,q (ℝn) ∩ L∞(ℝn) on itself.
Weak*–closed Jordan ideals of nest algebras
Authors: Oliveira Lina 
Published: January 2003

AbstractNest algebras provide examples of partial Jordan *–triples. If A is a nest algebra and As = A ∩ A*, where A* is the set of the adjoints of the operators lying in A, then (A, As) forms a partial Jordan *–triple. Any weak*–closed ideal in the nest algebra A is also an ideal in the partial Jordan *–triple (A, As). An analysis of the ideal structure of (A, As) shows that, for a large class of nest algebras, the converse is also true.
On q–deformed hyponormal operators
Authors: Ôta Schôichi 
Published: January 2003

AbstractThe present paper deals with operators in a Hilbert space related to the theory of quantum groups. Some results on q–deformed hyponormal operators extend ones on q–normal operators. For a q–deformed operator T the Cartesian decomposition of the inverse T–1 is characterized and the product BT with bounded operator B is analyzed, and a q–analogue of the Fuglede–Putnam theorem is discussed.
Littlewood–Paley type inequality on ℝ
Authors: Quek Tong Seng 
Published: January 2003

AbstractLet {Ik}k∈ℕ be a sequence of well–distributed mutually disjoint intervals of ℝ\{0}. For f ∈ Lp(ℝ), 1 ≤ p ≤ 2, define Sf by (Sf)ˆ = χ$\hat f $. We prove that there exists a positive constant C such that

for all f ∈ Lp(ℝ), 1 < p < 2, where 1/p + 1/p′ = 1 and ‖ · ‖p,p′ is the norm of the Lorentz space Lp,p′ (ℝ). An application of our result to Fourier multipliers is given.
The effect of the variational framework on the spectral asymptotics for two–parameter nonlinear eigenvalue problems
Authors: Shibata Tetsutaro 
Published: January 2003

AbstractWe consider the nonlinear two–parameter problemu″(x) + μu(x)p = λu(x)p,u(x) > 0, x ∈ I = (0, 1),u(0) = u(1) = 0,where 1 < q < p < 2q + 3 and λ, μ > 0 are parameters. We establish the three–term spectral asymptotics for the eigencurve λ = λ(μ) as μ → ∞ by using a variational method on the general level set due to Zeidler. The first and second terms of λ(μ) do not depend on the relationship between p and q. However, the third term depends on the relationship between p and q, and the critical case is p = (3q – 1)/2.
On the quotient of the representations of convexity and starlikeness
Authors: Tuneski Nikola 
Published: January 2003

AbstractLet f(z) = z + a2z2 + … be an analytic function in the unit disk 𝒰 = {z : |z| < 1}. Such a function belongs to the class Gb defined by Silverman if the quotient of the analytic representations of convexity and starlikeness of the function maps the unit disk into a disk with center 1 and radius b. By using the Jack lemma we analyze the relation between the class Gb and the class S*[A,B] and its subclasses.
Smallest and greatest fixed points of quasimonotone increasing mappings
Authors: Uhl Roland 
Published: January 2003

AbstractIn a Banach space E (pre)ordered by a cone we consider a mapping f : [v,w] → E (v,w ∈ E, v ≤ w) which satisfies v ≤ f(v) and f(w) ≤ w. We show that f has a smallest and a greatest fixed point, if it is continuous, quasimonotone increasing and condensing, in essence. Finally we admit discontinuities with upward jumps.
Dual‐wavelength optical short‐pulse generation and wavelength switching using multiple‐optical‐paths
Authors: Wang D. N. , Zhang M. , Li H. 
Published: January 2003

AbstractDual‐wavelength optical picosecond pulses are generated simultaneously by using a multiple‐optical‐path self‐seeding scheme. The external cavity of the Fabry–Perot (F–P) laser diode consists of three fiber Bragg gratings (FBGs) and a variable optical delay line. The wavelengths of the optical short pulses can be selected conveniently by adjusting the FBG and switched simply by adjusting the optical delay line. A side mode suppression ratio of better than 18 dB is achieved by using a 1:99 optical coupler to enhance the seeding power. The system is simple, easy to operate, and low cost. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 233–235, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10730
A real‐time approach to array control based on a learned genetic algorithm
Authors: Caorsi Salvatore , Donelli Massimo , Lommi Andrea , Massa Andrea 
Published: January 2003

AbstractIn the framework of wireless communications, it is mandatory to guarantee the reliability of the receiver by assuring good quality at the end‐user, in order to successfully decode transmitted signals. To this end, a method for the design of adaptive antenna arrays is described in this paper. The proposed procedure, based on a customized genetic algorithm, allows real‐time control of the receiver's performance by acting on the discretized phase coefficients of the array elements. As a result, at the receiver, multiple and alternating interferences are considerably reduced with respect to the desired signal. In order to validate the proposed strategy, selected numerical results, concerning various environment conditions, are presented and deeply discussed. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 235–238, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10731
Study on reduction in radiated emissions from PCB using test LSI
Authors: Haga Satoru , Nakano Ken , Sudo Toshio , Hashimoto Osamu 
Published: January 2003

AbstractRadiation mechanism and reduction measures have been studied using test large scale integrated (LSI) circuits. The LSI operation mode that simultaneously drives external traces radiates the greatest amount of emissions. In this mode, an LSI‐mounted area has been found to behave as an opening from the electromagnetic viewpoint. Two approaches under consideration, ferrite on the LSI package and a copper sheet covering the LSI package, were verified to reduce emissions very effectively. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 238–242, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10732
Reflection ellipsometry for in‐situ determination of complex permittivity and thickness of a single‐layer material at several angles of incidence and frequencies
Authors: Sagnard F. 
Published: January 2003

AbstractSeveral experimental results on common single‐layer samples have been obtained in the microwave domain using the reflection ellipsometry technique and two different data analysis procedures. They lead to estimations of complex permittivity as a function of the angle of incidence, frequency, and thickness. The influence of measurement uncertainties is discussed. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 243–248, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10733
A stopband filter design using a 1D non‐periodic defected ground structure
Authors: Irigoyen Ieltxu A. Garde , del Río Bocio Carlos 
Published: January 2003

AbstractThe one‐dimensional (1D) defected ground structure (DGS) is used to control the cut‐off frequency characteristic. In this paper three non‐periodic filters are built, in order to show the versatility of DGS. Five unit cells of different shape with the same attenuation pole frequency were combined in each filter. The frequency response is essentially the same as in the case of periodic filters with equal square unit cells. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 249–250, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10734
Analysis of microstrip patch arrays using the FDTD method
Authors: Abd El‐Raouf Hany E. , Ma Lai‐Ching , Yu Wenhua , Mittra Raj 
Published: January 2003

AbstractIn this paper, microstrip patch arrays with both uniform phase and tapered distributions are analyzed via the finite‐difference time‐domain (FDTD) technique. The phase delay in the frequency domain is converted into a delay in the time domain when exciting the array. The far field pattern of the array is calculated from its aperture distribution, in a plane located just above the array. A PMC plane has been employed to reduce the problem to half its size by invoking the symmetry of the problem. The results are found to be in good agreement with those derived by using the method of moments (MoM). © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 250–254, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10735
Dual‐band printed diversity dipole antenna for WLAN access point
Authors: Lee Gwo‐Yun , Chen Hong‐Twu , Wong Kin‐Lu 
Published: January 2003

AbstractA printed diversity dipole antenna suitable for applications in wireless local area network (WLAN) access points in the 2.4 GHz (2400–2484 MHz) and 5.2 GHz (5150–5350 MHz) bands is presented. The antenna comprises two stacked printed dipoles placed back‐to‐back. Each stacked dipole consists of two larger dipole arms for 2.4‐GHz band operation and two smaller dipole arms for 5.2‐GHz band operation. In addition, the proposed antenna can provide spatial diversity, because the obtained radiation patterns of the two stacked dipoles are directional in two complementary half spaces and the access point can thus switch between the two stacked dipoles for WLAN communication with maximum signal strength. Experimental results of a constructed prototype are presented. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 254–257, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10736
Experimental results for a CW‐mode optically controlled microwave switch on a silicon‐based coplanar waveguide
Authors: Lee Sangil , Kuga Yasuo , Mullen Ruth Ann 
Published: January 2003

AbstractA CW‐mode optically controlled microwave switch (CW‐mode OMS) on a coplanar waveguide (CPW) for both a standard and a new design with carrier‐confinement structure is investigated. We experimentally show that it may not be possible to obtain less than 7 dB of insertion loss with the standard OMS, and the carrier diffusion limits the improvement of insertion loss in CW‐mode operation. We present a new design with a carrier‐confinement structure with silicon (Si) substrate etching to confine the optically generated free‐carriers. Less than 2 dB of insertion loss is obtained with the new carrier‐confined OMS. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 257–262, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10737
Concentrator and lens models for calculating the impulse response on IR‐wireless indoor channels using a ray‐tracing algorithm
Authors: Rodríguez Pérez Silvestre , Pérez Jiménez Rafael , González Hernández Oswaldo B. , Rabadán Borges José Alberto , Rodríguez Mendoza Beatriz 
Published: January 2003

AbstractThis paper presents concentrator and lens models for the detector and emitter, respectively, upon which a Monte Carlo ray‐tracing algorithm allows the evaluation of impulse response on infrared (IR) wireless indoor channels. We also present computer simulation results that show the effects of concentrator FOV and reception direction on the impulse response, received optical power, and channel rms delay spread, which allow us to propose structures for angle‐diversity receivers. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 262–267, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10738
Artificial magnetic conductors as reflectors for low sidelobe antenna arrays
Authors: Zhang Ying , Younis Marwan , Fischer Christian , von Hagen Jürgen , Wiesbeck Werner 
Published: January 2003

AbstractNoticeably lower sidelobe levels in aperture‐coupled patch antenna arrays are achieved by an artificial perfect magnetic conductor (PMC) reflector rather than a traditional reflector. The reduction of parallel‐plate modes is analyzed. The patterns of the antenna array are measured with both a perfect electric conductor (PEC) reflector and a PMC reflector. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 267–270, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10739
Design of LNA at 2.4 GHz using 0.25 μm CMOS technology
Authors: Yang Xiaomin , Wu Thomas X. , McMacken John 
Published: January 2003

AbstractTwo 2.4‐GHz fully integrated CMOS low‐noise amplifiers (LNA) have been designed in a 0.25‐μm CMOS process. Design procedure and simulation results are presented in this paper. In the design of differential LNA, a novel idea is proposed so that the die area can be greatly reduced. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 270–275, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10740
Analysis of rectangular microstrip patch antennas on spherical structures
Authors: Sipus Zvonimir , Burum Niksa , Bartolic Juraj 
Published: January 2003

AbstractIn this paper, the input impedance and radiation pattern of spherical rectangular patch antennas are studied. The electric field integral equation is numerically solved by applying the method of moments where the multilayer spherical structure is rigorously considered, using the spectral‐domain algorithm for calculating Green's functions. In order to avoid numerical problems, a modified vector–Legendre transformation and normalized Legendre polynomials are defined and applied to the solution procedure. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 276–280, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10741
Propagation of a femtosecond laser pulse of a few optical oscillations in a uniaxial crystal
Authors: Hovhannisyan David 
Published: January 2003

AbstractUsing the method of unidirectional waves, we numerically solve a wave equation that describes the vector propagation of a femtosecond laser pulse of few optical cycles in a uniaxial crystal. Propagation of the pulse in the direction normal to the optical axis is studied, taking into account both the second‐ and third‐order nonlinearity of the crystal. Conversion efficiency as a function of crystal length, pump intensity, and pulse duration is studied. As an example, the propagation of a femtosecond laser pulse of τ = 10 fs duration at λ = 810 nm in a 12‐μm thick LiNbO3 crystal is numerically modeled. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 280–285, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10742
Coupling reduction between groove‐backed antennas
Authors: Yang Dong I. , Eom Hyo J. , Ra Jung W. 
Published: January 2003

AbstractIn this paper, the behavior of radiation and coupling reduction between two groove‐backed antennas is investigated. An electric line current is placed inside a rectangular groove in a perfectly conducting plane. Fourier transform and series techniques are employed to express the scattered field. Boundary conditions are enforced to obtain simultaneous equations for the discrete modal coefficients, which are then solved in order to calculate the radiated and coupled fields. The behavior of coupling reduction and radiation is discussed in terms of the antenna geometries. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 285–289, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10743
An nth‐order expression of the frequency domain impulse response of a synthetic aperture system and its applications
Authors: Gimeno‐Nieves E. , Lopez‐Sanchez J. M. , Bara M. 
Published: January 2003

AbstractA new compact generalized formula of the impulse response of a synthetic aperture system in the frequency domain is presented. This expression affords an improvement of chirped radar and sonar imaging techniques in wide‐band high‐resolution configurations. A new accurate and efficient chirp‐scaling algorithm has been reformulated by including an nth‐order expansion. This new algorithm has been implemented and tested, yielding more accurate images than the conventional CSA. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 289–292, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10744
Capacitively‐loaded CPW shunt stub notch filters
Authors: Singh R. Baliram , Weller T. M. , Smith M. C. , Culver J. W. 
Published: January 2003

AbstractThis paper describes optimal coplanar waveguide (CPW) 2nd harmonic notch filters that utilize metal‐insulator‐metal (MIM) capacitors at each discontinuity, eliminating the need for conventional air‐bridges and significantly reducing the filter footprint. The circuits were fabricated on a high resistivity, 400 μm‐thick silicon substrate. Theoretical and experimental data for 42 GHz notch filters employing straight and bent shunt stubs are presented. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 292–295, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10745
A novel frequency‐reconfigurable patch antenna
Authors: Xiao Shaoqiu , Wang Bing‐Zhong , Yang Xue‐Song 
Published: January 2003

AbstractA novel frequency‐reconfigurable patch antenna is proposed and analysed using the finite‐difference time‐domain (FDTD) method. The simulated results indicate that the antenna is capable of shifting its operating frequency over a one‐octave bandwidth from 0.6 GHz to 1.2 GHz with the radiation pattern essentially unaffected by the frequency tuning. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 295–297, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10746
An athermal, hitless, tunable add‐drop module with inherently integrated power controller
Authors: Yin Shizhuo , Purwosumarto Purwadi , Su Weihong , Luo Claire , Sheng Yunlong 
Published: January 2003

AbstractIn this paper, a small‐footprint, athermal, hitless, reconfiguration‐optical add‐drop module with an inherently integrated optical power controller is presented. This unique multiplexer cannot only add‐drop any wavelength among designed wavelength channels without interrupting through traffic, but can also dynamically control the output power of an add‐drop channel. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 297–300, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10747
A 3D posteriori error estimator for FEM solution of electromagnetic problems
Authors: Ezzedine Tahar , Kouki Ammar B. , Bouallegue Ammar 
Published: January 2003

AbstractWe introduce a new method for computing a posteriori error estimator suitable for the finite‐element solution of 3D electromagnetic problems. We take into account both the error due to discontinuity on the elements' faces as well as the volumetric error. We demonstrate the efficiency of the error estimator. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 300–302, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10748
Accurate determination of Q factors of a quasi‐optical resonator
Authors: Kapilevich B. , Faingersh A. , Gover A. 
Published: January 2003

AbstractThis paper presents a novel approach to measuring the Q factors of a quasi‐optical resonator used in a free electron maser (FEM) operating at 100 GHz. Estimation of the Q factors is based on measuring the reflection coefficient in the vicinity of resonance frequencies. The unknown parameters (attenuation constant and coupling inductance) are determined from the numerical solution of a nonlinear system of two equations. As an example, the Q factors of a quasi‐optical resonator, based on the shorted‐line waveguide section, have been determined using the proposed method. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 303–306, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10749
A transmission line model applied to shaped slot dielectric‐filled waveguide antennas
Authors: Chainon S. , Himdi M. 
Published: January 2003

AbstractThis paper presents an extension of the so‐called transmission line model method (TLMM) applied to shaped slot dielectric‐filled waveguide antennas (SDFWAs), especially the L‐shaped slot. This radiating longitudinal slot is fed by a transversal slot used as a coupling element; their association is shaped like the letter L. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 306–310, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10750
Dual‐mode double‐ring resonator for microstrip band‐pass filter design
Authors: Liu Ji‐Chyun , Cheng Chin‐Shen , Yao Leo 
Published: January 2003

AbstractA novel design of a dual‐mode resonator with double‐ring structure for a band‐pass filter is presented in this paper. Voltage/current couplings between the two rings are proposed based on a mode chart. Because each ring exhibits dual‐mode responses, they determine the range of operation; that is, the inner/outer rings depict the upper/lower frequencies of the pass band, respectively. This is an alternative approach to improve the bandwidth of the conventional dual‐mode ring resonator. Experimental results are presented and discussed. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 310–314, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10751