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21.
H. G. Miller Yiharn Tzeng G. D. Yen N. Canosa R. Rossignoli A. Plastino 《Zeitschrift für Physik A Hadrons and Nuclei》1986,356(2):141-144
Unphysical behavior in the QR algorithm based least squares determination of the expansion coefficients of the charge density obtained from limited information about the charge form factor occurs when the spread of the singular values in the matrix relating these quantities becomes too large. Setting the smallest singular values equal to zero in the singular value decomposition used in the minimum norm method yields a much more reasonable determination of the charge density. Increasing the size of the basis without increasing the range of the prior information about the charge form factor leads to ambiguities in the determination of the charge density. Numerical results in an analytic model are presented. 相似文献
22.
Wen-Shing Tsai Shah-Jye Tzeng Shih-Hung Chen Tzu-Shen Chien 《Optics Communications》2006,263(2):201-206
A bidirectional hybrid dense-wavelength-division-multiplexing (DWDM)-passive optical network (PON) employing optical injection locking technique on vertical-cavity surface-emitting lasers (VCSELs) and data comparator, as well as optical injection locking technique on distributed feedback laser diodes (DFB LDs) and amplitude/phase compensator is proposed and demonstrated. Improved performances of bit error rate (BER) and carrier-to-noise ratio/composite second order/composite triple beat (CNR/CSO/CTB) were observed in our proposed bidirectional hybrid DWDM-PON. Bidirectional transmission in bidirectional hybrid DWDM-PON architecture is a very attractive option, the capacity of the optical network can be expanded relatively easily by bidirectional transmission technology. 相似文献
23.
Ouyang H Lin KW Liu CC Lo SC Tzeng YM Guo ZY van Lierop J 《Physical review letters》2007,98(9):097204
A Ni80Fe20/(Ni,Fe)O thin film exhibits a positive exchange bias when cooled in a zero field and a negative exchange bias when field cooled. With transmission electron microscopy and electron energy loss spectrometry, the composition and magnetic structure has been ascertained and a distribution of magnetization easy axes about the interface extrapolated. The results indicate that the positive exchange bias is from antiferromagnetic interface moments perpendicular to their ferromagnetic counterparts. With field cooling the alignment is put into a parallel configuration resulting in a negative exchange bias. 相似文献
24.
This work experimentally studies the flow characteristics and forced convective heat transfer in a sintered porous channel
that filled with sintered copper beads of three average diameters (
0.830, and 1.163 mm). The pressure drop and the local temperature measurements can be applied to figure out the distributions
of the friction coefficient and the heat transfer coefficient. Three sintered porous channels differ in the arrangement of
obstacle blocks. Model A has no obstacle. Models B and C have five obstacle blocks facing down and up, respectively, in a
sintered porous channel. The range of experimental parameters, porosity, heat flux, and effect of forced convection are 0.370
≤ ɛ ≤ 0.385, q=0.228, 0.872, 1.862 W/cm2, and 200 ≤ Re
d ≤ 800. The permeability and inertia coefficient of each of the three sintered porous channels are analyzed. The results for
Model A agree with those obtained by previous investigations in C
f distribution. The heat transfer of Model C exceeds that of Model A by approximately 20%. Finally, a series of empirical correlation
equations were obtained for practical applications and engineering problems. 相似文献
25.
This study analyzed variations of tribological behaviors that depend on the injection molding techniques during the blending of short glass fiber (SGF) and polytetrafluoroethylene (PTFE) reinforced polycarbonate (PC) composites. The proposed planning of blending experiments is to use a D‐optimal mixture design (DMD). The tribological behaviors of friction coefficient and wear mass loss were selected for discussion. Nine experimental runs, based on a DMD method, utilized to train the back‐propagation neural network (BPNN) and then the simulated annealing algorithm (SAA) approach is applied to search for an optimal mixture ratio setting. In addition, the result of BPNN integrating SAA was also compared with response surface methodology (RSM) approach. The results of confirmation experiment show that DMD, RSM, and BPNN integrating SAA method are effective tools for the optimization of reinforced process. Furthermore, the scanning electron microscope (SEM) images show that the abundant debris are peeled off from the matrix materials and predominant delamination mechanisms and plastic deformation are shown on the worn surface after tribological behavior tests. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
26.
Tseng CH Chen YL Chung KY Wang CH Peng SI Cheng CM Tzeng CC 《Organic & biomolecular chemistry》2011,9(9):3205-3216
A number of 2,3-diarylquinoline derivatives were synthesized and evaluated for antiproliferative activities against the growth of six cancer cell lines including human hepatocellular carcinoma (Hep G2 and Hep 3B), non-small cell lung cancer (A549 and H1299), and breast cancer (MCF-7 and MDA-MB-231) cell lines. The preliminary results indicated that 6-fluoro-2,3-bis{4-[2-(piperidin-1-yl)ethoxy]phenyl}quinoline (16b) was one of the most active compounds against the growth of Hep 3B, H1299, and MDA-MB-231 with a GI(50) value of 0.71, 1.46, and 0.72 μM respectively which was more active than tamoxifen. Further investigations have shown that 16b induced cell cycle arrest at G2/M phase followed by DNA fragmentation via an increase in the protein expression of Bad, Bax and decrease in Bcl-2, and PARP which consequently cause cell death. 相似文献
27.
Synergy effects are the motives to enter into strategic alliances; however due to lack of adequate preparation or planning, these alliances often fail. It is of no doubt that a successful strategic alliance depends on choosing the correct alliance partners and appropriate resource allocation. In this paper, the fuzzy multi-objective dummy programming model is proposed to overcome the above-mentioned problems. Two types of strategic alliances, joint ventures and mergers and acquisitions (M&A), are demonstrated to choose the best alliance partners and allocate the optimal alliance resources in a numerical example. Based on the results, our method can provide the optimal alliance cluster and satisfaction in strategic alliances. 相似文献
28.
Decker C.D. Mori W.B. Kuo-Cheng Tzeng Katsouleas T.C. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1996,24(2):379-392
We investigate electron acceleration from space-charge waves driven by single-frequency lasers using a fully explicit particle-in-cell (PIC) model. The two dimensional (2-D) simulations model ~100 fs pulses at densities near n=4×1019 cm-3 for 1-μm lasers. The pulses are found to break up due to a combination of longitudinal and transverse bunching of the laser intensity via Raman forward scattering type instabilities. The ponderomotive force of these intensity modulations generates large amplitude plasma waves. Large numbers of self-trapped electrons and multiple Raman forward scattering satellites are observed. The relevance of these simulations to experiments is discussed 相似文献
29.
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