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171.
This paper presents supplier–buyer models to describe the bargaining process between a supplier and a buyer over a long-term replenishment contract. Two different models are developed: one for the situation where the supplier has superior bargaining power over the buyer, and the other for the reverse situation. For each model, a method is derived that employs game theory-based analysis to determine the best strategy for each agent. A computational experiment is conducted to estimate the efficiency of the methods and to determine the economic implications of the results. The result indicates that each algorithm is very efficient compared to other strategies. We also verify that the solutions derived from each model are Nash equilibrium. Significantly improved outcomes are obtained for both agents by agreeing to the terms generated by the algorithms over the terms selected in the usual manner. 相似文献
172.
Deale O.C. Ng K.T. Kim E.J. Lerman B.B. 《IEEE transactions on bio-medical engineering》1995,42(12):1208-1211
A high common mode voltage (Vcm) relative to earth ground is produced on the myocardium during the delivery of a defibrillator pulse and can generate a differential error signal when potential gradients are recorded with bipolar electrodes and isolation amplifiers. The error signal is proportional to Vcm, and therefore, a reduction in Vcm improves the accuracy of the potential gradient data. Experiments were conducted on 5 dogs to determine whether Vcm can be controlled using a bridge circuit. The bridge circuit consisted of a 5 kΩ power rheostat in parallel with the transthoracic resistance of the dog. The variable contact of the rheostat was connected to earth ground, and by adjusting the rheostat, Vcm on the myocardium could be varied. In each dog, 20 A shocks were delivered through stainless steel transthoracic electrodes. Point contact electrodes sutured to the epicardium were used to measure Vcm. It was determined that Vcm could be reduced to approximately zero at a given electrode on the heart. In addition, for the 5 dogs studied, the maximum measured Vcm on the heart was only 10% of the transthoracic voltage when the bridge circuit was balanced for an interior point in the heart 相似文献
173.
Green R.P.M. Crofts G.J. Hubbard W. Udaiyan D. Dong Hwan Kim Damzen M.J. 《Quantum Electronics, IEEE Journal of》1996,32(3):371-377
We demonstrate that self-induced gain gratings can provide nonlinear optical feedback that results in single frequency selection and passive self Q-switching of a conventional linear laser cavity. An experimental Nd:YAG laser system is described that yields a temporally-smooth 20 ns pulse at 1.064 μm. In addition, we show that the feedback has phase-conjugate properties that permit “flower-like” mode formation even though the azimuthal symmetry of the cavity is broken 相似文献
174.
Joo-Wan Kim Byung Sung Kim Sangwook Nam Choong Woong Lee 《Antennas and Propagation, IEEE Transactions on》1996,44(7):996-999
To specify manufacturing tolerances of a reflector antenna, various errors such as random surface errors and misalignment errors must be considered at one time because superposition of the effects of those errors may not hold. Based on the Rahmat-Samii's formulation (1983), a method for computing efficiently the average power pattern of a reflector antenna with those errors is presented. Simulation results show that superposition of the effects of errors does not generally hold and demonstrate how those errors degrade the peak-gain and sidelobe levels 相似文献
175.
Young-Bae Seu Taeg-Kyeong Lim Chang-Jin Kim Sun-Chul Kang 《Tetrahedron: Asymmetry》1995,6(12):3009-3014
Optically active epoxy alcohol, (R)-2-butyryloxymethylglycidol3 which is the precursor of a tert-alcohol chiral building block was obtained in high enantiomeric purity, 98.7% e.e., by lipase-catalyzed asymmetric hydrolysis using a phosphate buffer and organic co-solvent system in 95% of chemical yield. 相似文献
176.
The chemical mechanism of the precipitation of lead titanium peroxohydroxide particles in a solution of nitrilotriacetate (NTA) complexes of lead and titanium peroxo-hydroxide is envisioned as the interaction between cations of lead hydroxide and anions of polymeric titanium peroxo-hydroxide. 相似文献
177.
Ha J.H. Kim S.W. Seol Y.S. Park H.K. Choi S.H. 《Semiconductor Manufacturing, IEEE Transactions on》1996,9(2):289-291
The plug loading effect occurring during the etchback of tungsten was investigated in a magnetically enhanced reactive ion etcher using SF 6/Ar mixtures. It was found that while the plug loading effect is independent of varying SF6/Ar flow rate ratio and magnetic field intensity, it is reduced under the condition of high selectivity of tungsten relative to TiN which was achieved at high chamber pressure and low RF power. It is proposed that when TiN is used as a glue layer, the W etch rate enhancement in the plug is mainly controlled by a local loading effect. Under the optimized etchback conditions the plug loss was successfully controlled without the tungsten residue left on severe topology 相似文献
178.
Byeong Gi Lee Seok Chang Kim 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1995,83(10):1399-1428
This paper discusses recent advances in the theory and applications of scrambling techniques for digital lightwave transmission. It introduces the theories of sequence space and shift register generator (SRG) space which enable systematic analysis and mathematical manipulation of the behavior of sequences in general and the related SRG's. It discusses the behavior and realization of frame synchronous scrambling (FSS) and distributed sample scrambling (DSS) with emphasis on parallel sequences and the related parallel SRG's (PSRG). In addition, it describes self synchronous scrambling (SSS). Then the paper applies the theories to today's lightwave transmission systems by demonstrating practical parallel designs of FSS for SDH/SONET transmission, DSS for cell-based ATM transmission, and SSS for SDH-based ATM transmission. It finally considers how DSS can be used for scrambling of mixed isochronous and nonisochronous data in future high-speed data networks. The paper employs various new concepts and terminology, such as PSRG engine, generating vector discrimination matrix, (M,N) PSRG, sampling vector, correction vector, correction matrix, predictable scrambling concurrent sampling, and immediate correction 相似文献
179.
Sungwon Kim Zuo Wang Hagan D.J. Van Stryland E.W. Kobyakov A. Lederer F. Assanto G. 《Quantum Electronics, IEEE Journal of》1998,34(4):666-672
We demonstrate and compare two phase-insensitive all-optical transistors (AOT's) based on frequency-degenerate quadratic three-wave interactions. In particular, we demonstrate gain using KTP in a type II geometry. Both AOT's exploit the phase insensitivity inherent to three-wave parametric processes when only two fields are input, providing amplification of a small signal at the operating frequency via the interaction with a second-harmonic wave. The first scheme is based on successive up- and down-conversion (i.e., cascading) while the second relies on parametric down-conversion. We obtain gains of 5 and 160 in the two configurations, respectively, with a significant background and output coherent to the pump in the first case, no background and coherence between output and signal in the second 相似文献
180.
Dongwook Park Minnyeon Kim 《Quantum Electronics, IEEE Journal of》1996,32(8):1432-1440
This paper presents theoretical results on mode characteristics of surface-emitting (SE) lasers utilizing an active second-order grating section. Based on a coupled-mode approach, longitudinal modes and the associated space-harmonic transverse modes are calculated via a numerical technique. From these, the lasing-mode spectrum, near- and far-field patterns of the radiation mode, and the surface-emission power efficiency are obtained. Effects of the substrate reflector and the grating parameters are also investigated. Finally, comparisons are made with conventional, edge-emitting DFB lasers. The results indicate that with a suitable choice of structural parameter values, DFB SE lasers can be made to possess both the spectral discrimination of the conventional DFB lasers and the advantages of SE lasers at the same time and also that the second lowest longitudinal mode may be preferred over the fundamental longitudinal mode for many applications due to its symmetric field distribution 相似文献