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201.
A systematic study of the upper semicontinuity and the lower semicontinuity of the solution map in parametric affine variational inequalities is given in this paper. Several examples are constructed to analyze the results. This work was supported by Korea Research Foundation Grant (KRF 2001-015-DP0049), the APEC Postdoctoral Fellowships Program, and the KOSEF Brain Pool Program.  相似文献   
202.
On the harmonic Bergman space of the half-space, we give characterizations for an arbitrary positive Toeplitz operator to be a Schatten (or Schatten-Herz) class operator in terms of averaging functions and Berezin transforms. Examples are provided to show that various results are sharp. This research was supported by KOSEF(R01-2003-000-10243-0).  相似文献   
203.
Nitrided gate oxides offer several electrical and reliability advantages over conventional oxides and also provide a good barrier against impurity diffusion. Oxidation in nitrous oxide (N2O) has been very successful in overcoming some of the problems associated with nitridation in ammonia. The authors have observed that the extent of N2O oxidation has a strong detrimental effect on the drain leakage current of MOS transistors in the off state. This phenomenon has been identified to be caused by an increase in the active area junction leakage current  相似文献   
204.
We demonstrated a unified two-band broadband light source based on erbium-doped fiber. The proposed scheme generates high output power at both bands and saves doped-fiber and pump lasers.  相似文献   
205.
Lee  J.J. Mawst  L.J. Botez  D. 《Electronics letters》2003,39(17):1250-1252
Doping the waveguide core (p=2/spl times/10/sup 17/ cm/sup -1/) in asymmetric-waveguide InGaAs/InGaAsP, two-quantum-well diode lasers (/spl lambda/=980 nm) raises the injection efficiency to 90% and decreases the threshold-current density, J/sub th/. For 2 mm long, 100 /spl mu/m wide stripe, uncoated chips J/sub th/ decreases from /spl sim/188 A/cm/sup 2/ to /spl sim/150 A/cm/sup 2/. High characteristic temperatures for J/sub th/ and the slope efficiency are obtained: T/sub 0/=215K and T/sub 1/=600K.  相似文献   
206.
Currently, self-organized magnetic array (SOMA) is a non-oriented media, with randomly distributed easy axis directions. We investigate the recording performance of SOMA under two different head types—Ring Head (RH) and single pole head (SPH). Our results show an interesting dependence of the recorded transition pattern on the field strength of RH, where a weak RH field generates longitudinal transition pattern and a strong RH field generates a perpendicular transition pattern in the media. The SPH only generates perpendicular transition patterns and has a higher signal-to-noise ratio (SNR) than that of the RH.  相似文献   
207.
Let G(x,y) and GD(x,y) be the Green functions of rotationally invariant symmetric α-stable process in Rd and in an open set D, respectively, where 0<α<2. The inequality GD(x,y)GD(y,z)/GD(x,z)?c(G(x,y)+G(y,z)) is a very useful tool in studying (local) Schrödinger operators. When the above inequality is true with c=c(D)∈(0,∞), then we say that the 3G theorem holds in D. In this paper, we establish a generalized version of 3G theorem when D is a bounded κ-fat open set, which includes a bounded John domain. The 3G we consider is of the form GD(x,y)GD(z,w)/GD(x,w), where y may be different from z. When y=z, we recover the usual 3G. The 3G form GD(x,y)GD(z,w)/GD(x,w) appears in non-local Schrödinger operator theory. Using our generalized 3G theorem, we give a concrete class of functions belonging to the non-local Kato class, introduced by Chen and Song, on κ-fat open sets. As an application, we discuss relativistic α-stable processes (relativistic Hamiltonian when α=1) in κ-fat open sets. We identify the Martin boundary and the minimal Martin boundary with the Euclidean boundary for relativistic α-stable processes in κ-fat open sets. Furthermore, we show that relative Fatou type theorem is true for relativistic stable processes in κ-fat open sets. The main results of this paper hold for a large class of symmetric Markov processes, as are illustrated in the last section of this paper. We also discuss the generalized 3G theorem for a large class of symmetric stable Lévy processes.  相似文献   
208.
209.
A practical approach is demonstrated for the deterministic analysis of surface distortions in reflector antennas, based on a first-order approximation to the aperture field phase. Measured pattern results from the 15-m-diameter hoop/column deployable mesh reflector antenna are used to demonstrate the accuracy which can be obtained with this surface distortion analysis. The only practical limitation of the first-order approximation is determined by the slope derivations of the distorted surface from the best-fit paraboloid  相似文献   
210.
This paper studies the tail behavior of the fundamental period in the MAP/G/1 queue. We prove that if the service time distribution has a regularly varying tail, then the fundamental period distribution in the MAP/G/1 queue has also regularly varying tail, and vice versa, by finding an explicit expression for the asymptotics of the tail of the fundamental period in terms of the tail of the service time distribution. Our main result with the matrix analytic proof is a natural extension of the result in (de Meyer and Teugels, J. Appl. Probab. 17: 802–813, 1980) on the M/G/1 queue where techniques rely heavily on analytic expressions of relevant functions. I.-S. Wee’s research was supported by the Korea Research Foundation Grant KRF 2003-070-00008.  相似文献   
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