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991.
We propose a preconditioning of the Dirac operator based on the factorisation of a predefined function related to the decay of the propagator with the distance. We show that it can improve the accuracy of correlators involving heavy quarks at large distances and accelerate the computation of light quark propagators. 相似文献
992.
A direct and unifying scheme for disclosure of periodic wave solutions of both nonlinear differential and difference equations is presented. The scheme is based on Hirota's bilinear form and certain Riemann theta function formulae. The relations between the periodic wave solutions and soliton solutions are rigorously established. 相似文献
993.
Rajiv Manohar Abhishek Kumar Misra Satya Prakash Yadav A.K. Prajapati 《Journal of Physics and Chemistry of Solids》2010,71(12):1684-1689
Dielectric measurements have been carried out for the determination of real and imaginary parts of the permittivity of a newly synthesized, unusually shaped liquid crystal. The sample has been investigated in the frequency range from 100 Hz to 10 MHz within a temperature range 80-130 °C. The dielectric measurements in the smectic A phase indicate a Cole-Cole type of dispersion, and the activation energy was found to be 5.5 meV by using the Arrhenius plot of relaxation time. In addition to this, thermal and optical transmittance studies have also been conducted in the above mentioned temperature range, and the temperature dependence of these parameters has been discussed in detail. The phase transition temperature obtained from a differential scanning calorimetry (DSC) study matches within 2 °C that was obtained from an optical transmittance study. The dielectric and optical behavior of the unusually shaped liquid crystal has been explained on the basis of a proposed theoretical model in which a sample possesses two different conformers having induced polarizations in opposite directions. 相似文献
994.
995.
Differential output-ports choosing probability (DOCP) scheme is a novel traffic outputting model for core router in optical burst switching (OBS) network. In this paper, we provide an analytical model for studying the performance of traffic blocking and delay in DOCP-applied OBS network. We first evaluate blocking probabilities using DOCP and confirm it by simulation. Then, in optical buffer-equipped OBS core router, we consider the average delay time for buffered traffic and the average total traffic queueing length in core router. The knowledge of delay performance is useful for the optical buffer architecture configuration in differential traffic scenario. Several results indicate that, under the same load condition, the blocking probabilities and the delay time will change along with the changeable ports choosing probability and the ratio between different length bursts in the OBS system. 相似文献
996.
“与密钥模2~n加运算”的差分性质研究 总被引:1,自引:0,他引:1
“与密钥K模2n加”-Y=X+Kmod2n是密码算法中一个常用的基本编码环节,在SAFER++,RC6 Phelix等算法中有广泛的应用。该文对Y=X+Kmod2n进行了差分分析,首次给出了当差分转移概率取最大值1,次大值1-1/2n-2,次小值1/2n-2以及1/2时,输入差,输出差及密钥的结构特点和计数公式。 相似文献
997.
针对大型和中小型企业对信息化需求的不同特点,介绍了国外传统固网运营商、移动运营商和全业务运营商向不同企业提供信息化服务的具体做法,从而提出了中国国内运营商企业信息化服务的市场策略和需要注意的事项。 相似文献
998.
999.
Serife Nur Deveci Tuncer Acar Osman Alagoz 《Mathematical Methods in the Applied Sciences》2020,43(5):2772-2782
In this study, we introduce newly defined Gamma operators which preserve constants and e2μ·, μ>0 functions. In accordance with this purpose, we focus on their approximation properties such as uniform convergence, rate of convergence, asymptotic formula, and saturation results. Superior properties of introduced operators have been tested both theoretically and numerically in certain senses to highlight the performance of the new constructions of Gamma operators. 相似文献
1000.
以南京地铁环控系统自联调以来各种设备(冷水机组,风机及电控柜等)出现的故障为案例,就设计,采购及维护方面分析了空调通风系统设备故障原因并就提出一些改善方法。 相似文献