排序方式: 共有12条查询结果,搜索用时 15 毫秒
1.
Sin-sheng Shei 《Nuclear Physics B》1979,156(2):225-236
We study the change of one two-point function of hadronic electromagnetic currents in the presence of background gauge fields. It is found that it has the asymptotic behavior of 1/q4 as compared to ln(-q2) behavior from the bare fermion loop contribution. The effects of the non-perturbative vacuum in QCD on the two-point function is studied in an explicit calculation. We obtain the same qualitative behavior as in our general discussion. The effects on the total hadronic e+e? annihilation is also discussed. We find that the effect ΔRI/R is of the order of o(1/q4) or O(1/q6). This may explain the precocious scaling in the e+e? annihilation. 相似文献
2.
Sun-Sheng Shei 《Physics letters. [Part B]》1978,79(3):245-248
We propose a new variable for studying the deviation from perfect two-jet structure in e+e? annihilation. This involves only charged particles in the final state. We calculate this in QCD. We also discover a strong-interaction independent prediction in e+e? annihilation. 相似文献
3.
We report on an improved configuration to monitor a passive optical network with high quality in service. This proposed system comprises fiber-Bragg gratings, a 1 × 4 optical switch, and an optical time-domain reflectometry to diagnose the broken point in real time. It could simultaneously detect multioptical network units in a WDM PON. The remote-pump integrated residual pumping reused function is implemented. Broken points in different optical paths can be detected simultaneously even when the distances to the central office are identical. The bit-error rate testing is verified with a small power penalty, making it an ideal solution for the real-time monitoring in a WDM PON. 相似文献
4.
Dian-Hau Chen Shyang-Roeng Sheen Chau-Ting Chang Cheng-Yie Shei Weir-Mirn Hurng 《中国化学会会志》1992,39(2):137-142
To prepare the YBa2Cu3Oy (Y-123) and (Bi, Pb)2(Sr, Ca)4Cu3Oy (Bi-2223) superconductive materials, coprecipitation was used with 8-hydroxyquinoline (oxine) as precipitant to ensure complete precipitation. Various aspects of competitive reactions such as dissociation, precipitation, complex formation and association in the aqueous solution system containing metal ions, oxinate ion and diethylamine species have been explored in order to discover the optimal coprecipitation conditions of the title system. Experiments were conducted to confirm these conditions. 相似文献
5.
Chern-Sheng Lin Chia-Tse Chen Hung-Jung Shei Yun-Long Lay Chuang-Chien Chiu 《Optics & Laser Technology》2012,44(6):1934-1941
This study develops a body motion interactive system with computer vision technology. This application combines interactive games, art performing, and exercise training system. Multiple image processing and computer vision technologies are used in this study. The system can calculate the characteristics of an object color, and then perform color segmentation. When there is a wrong action judgment, the system will avoid the error with a weight voting mechanism, which can set the condition score and weight value for the action judgment, and choose the best action judgment from the weight voting mechanism. Finally, this study estimated the reliability of the system in order to make improvements.The results showed that, this method has good effect on accuracy and stability during operations of the human–machine interface of the sports training system. 相似文献
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Localized molecular orbitals have been shown to be transferable among structurally-related molecules. We further show that the electronic energies between localized orbitals are transferable and their magnitude can be estimated. A set of parameters of group interaction energies are established from the analysis of small molecules. Use of these parameters is demonstrated successfully for large molecules. 相似文献
8.
Shyang-Roeng Sheen Maw-Kuen Wu Cheng-Yie Shei Weir-Mirn Hurng Dian-Hau Chen Chau-Ting Chang 《中国化学会会志》1996,43(4):321-326
A superconducting (Bi, Pb)2(Sr, Ca)4Cu3O2 material has been prepared by tbe oxalate coprecipitation method. The high-Tc 110 K phase was effectively promoted by application of an intermediate grinding and pressing between the sintering heat treatments. The powder X-ray diffraction shows the existence of single high-Tc and high-textured microstructures with strong (001) reflections within a short sintering time ( 18 h). The morphology of the sintered samples was examined by scanning electron microscopy (SEM). Also, the kinetics of the formation of the high-Tc phase were investigated by the isothermal method. A possible mechanism of the formation of high-Tc 2223 phase was proposed. 相似文献
9.
We study SU(N) scalar quantum chromodynamics in two space-time dimensions in the large-N limit. This is the model of color gauge fields interacting with scalar quarks. We find that the consensual properties of four-dimensional QCD, i.e. infrared slavery, quark confinement, the charmonium picture, etc. are all realized. Moreover, the current in this model mimics nicely the behavior of the current in four-dimensional QCD, in contrast to the original model of 't Hooft. 相似文献
10.
H.M. Lo Y.T. Hsieh S.C. Shei Y.C. Lee X.F. Zeng W.Y. Weng N.M. Lin S.J. Chang 《Superlattices and Microstructures》2010
The authors applied a simple, low-cost, mass-producible contact-transferred and mask-embedded lithography (CMEL) to texture p-GaP window layer for the fabrication of InGaAlP light-emitting diodes (LEDs) emitting at 612 nm. Under 20 mA current injection, it was found that forward voltages were 2.25, 2.24 and 2.25 V for CMEL-400 nm LED, CMEL-2 μm LED and the conventional LED without CMEL, respectively. It was also found that the 20 mA output powers were 1.43, 1.28 and 1.16 mW for CMEL-400 nm LED, CMEL-2 μm LED and the conventional LED without CMEL, respectively. 相似文献