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991.
二层信用策略下部分延期付款的库存模型 总被引:1,自引:0,他引:1
当前二层信用期相关文献考虑的都是零售商提供给其顾客相同的信用期,但现实中零售商往往会根据物品的种类不同提供给顾客不同的信用期.为研究此问题,建立了优化供货周期使零售商平均相关成本最小的库存模型,证明了最优供货周期的存在性,并给出实例加以说明. 相似文献
992.
993.
Jiangfeng Luan 《Optik》2011,122(2):168-172
The temporal intensity distributions of the transmitted light through the tissue with lesion structures are investigated using the polarized Monte Carlo technique. Simulation results show that time-resolved curves of transmitted light change obviously for different lesion structures. When the lesion thickness increases, the intensity of transmitted light decreases for co-polarization detection and increases for cross-polarization detection. With the increase of the lesion depth, the amplitude rises for both co- and cross-polarization detection. A method considering the dependence of the peak temporal distribution on the lesion position is thus proposed to locate lesions inside live tissues. 相似文献
994.
Norio Kondo 《国际流体数值方法杂志》2012,70(2):158-185
We present numerical results for in‐line and cross‐flow vibrations of a circular cylinder, which is immersed in a uniform flow and is elastically supported by damper‐spring systems to compute vibrations of a rigid cylinder. In the case of a circular cylinder with a low Scruton number, it is well‐known that two types of self‐excited vibrations appear in the in‐line direction in the range of low reduced velocities. On the other hand, a cross‐flow vibration of the circular cylinder can be excited in the range of high reduced velocities. Therefore, we compute the flow‐induced vibrations of the circular cylinder in the wide range of the reduced velocities at low and high Scruton numbers and discuss about excitation mechanisms in the in‐line and cross‐flow directions. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
995.
996.
Studies of temperature dependences of ac magnetization were carried out for a superconducting lead-porous glass nanocomposite. Double peaks were found on the imaginary part of ac magnetization which were accompanied with double steps on the real part. The lower-temperature anomalies in ac magnetization differed noticeably when they were obtained upon cooling and warming. The double peaks were treated as two phase transitions in the vortex system: the liquid-solid transition which occurs close to the onset of superconductivity and solid-solid one which is triggered by superconductivity in confined lead islands. 相似文献
997.
构造了S^1上S^3|H-丛的所有复结构的模空间,其中丛的转换函数u:s^3/H→S^3/H是S^3/H的一个对合,HU(2),H为有限群且在S^3/H上的作用是自由的。真不连续的。 相似文献
998.
999.
C. Raghu Indranil Rudra Diptiman Sen S. Ramasesha 《Journal of Chemical Sciences》2001,113(5-6):459-486
One of the fascinating fields of study in magnetism in recent years has been the study of quantum phenomena in nanosystems.
While semiconductor structures have provided paradigms of nanosystems from the stand point of electronic phenomena, the synthesis
of high nuclearity transition metal complexes have provided examples of nano magnets. The range and diversity of the properties
exhibited by these systems rivals its electronic counterparts. Qualitative understanding of these phenomena requires only
a knowledge of basic physics, but quantitative study throws up many challenges that are similar to those encountered in the
study of correlated electronic systems. In this article, a brief overview of the current trends in this area are highlighted
and some of the efforts of our group in developing a quantitative understanding of this field are outlined. 相似文献
1000.
The objective of this work is to determine the maximum stretch of the C–C bond before it misses the character of single bond, employing both the Atoms in Molecules (AIM) and Electron Localization Function (ELF) methods. It was concluded that C–C distances up to 2.0 Å could be considered single bonds. 相似文献