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151.
HOU Zhao-Yu GUO Ai-Qiang 《理论物理通讯》2007,47(4):690-694
We modify the square of virtual photon four-momentum by using nuclear binding energy formula, and calculate the effect of nuclear binding energy to K factor and Compton subprocess and annihilate subprocess in A-A collision Drell-Yan process. The outcome indicates that the effect of nuclear binding energy to K factor is obvious in little x region and it would disappear gradually as x increases. 相似文献
152.
重力场与静电场特点的比较 总被引:2,自引:1,他引:1
“场”是一种客观存在的物质,但由于“场”具有不易直接感受的特殊存在形态,同学们对“场”的物质性的理解不够深刻,解决“场”的相关问题时也感到棘手.笔者就高中阶段最典型的两种场——“重力场”和“静电场”的力学性质与能量特点进行比较,使同学们对“场”的概念有更深刻的认识. 相似文献
153.
A straightforward process for the encapsulation of HbHNL under low methanol conditions has been developed. By adding a sol, prepared by hydrolysis of TMOS/MTMS at pH 2.8 with continuous removal of methanol, to a stirred solution of the enzyme in a buffer at pH 6.5, at least 65% of the activity of the free enzyme could be recovered after the encapsulation. The aquagels were successfully used in the synthesis of (S)-cyanohydrins. 相似文献
154.
冲击载荷下剪切断裂研究 总被引:1,自引:0,他引:1
利用Hopkinson压杆技术对单边平行双裂纹试样倒向加载,在较大的加载率范围,对Ti6Al4V钛合金和40CrNiMoA两种材料的动态剪切断裂行为进行了研究.实验结果表明:存在两类韧性剪切断裂模式,即常规的韧性剪切型断裂和绝热剪切断裂.常规剪切型断裂模式的断裂韧性KⅡd随加载率的提高而增大,而绝热剪切型的断裂韧性KⅡd则随加载率的提高而减小,并且,当加载率增大至某一临界值时,常规的韧性剪切断裂模式将转变为绝热剪切断裂破坏模式. 相似文献
155.
Subgame consistency is a fundamental element in the solution of cooperative stochastic differential games. In particular, it ensures that: (i) the extension of the solution policy to a later starting time and to any possible state brought about by the prior optimal behavior of the players would remain optimal; (ii) all players do not have incentive to deviate from the initial plan. In this paper, we develop a mechanism for the derivation of the payoff distribution procedures of subgame consistent solutions in stochastic differential games with transferable payoffs. The payoff distribution procedure of the subgame consistent solution can be identified analytically under different optimality principles. Demonstration of the use of the technique for specific optimality principles is shown with an explicitly solvable game. For the first time, analytically tractable solutions of cooperative stochastic differential games with subgame consistency are derived. 相似文献
156.
We propose a minimum mean absolute error linear interpolator (MMAELI), based on theL
1 approach. A linear functional of the observed time series due to non-normal innovations is derived. The solution equation
for the coefficients of this linear functional is established in terms of the innovation series. It is found that information
implied in the innovation series is useful for the interpolation of missing values. The MMAELIs of the AR(1) model with innovations
following mixed normal andt distributions are studied in detail. The MMAELI also approximates the minimum mean squared error linear interpolator (MMSELI)
well in mean squared error but outperforms the MMSELI in mean absolute error. An application to a real series is presented.
Extensions to the general ARMA model and other time series models are discussed.
This research was supported by a CityU Research Grant and Natural Science Foundation of China. 相似文献
157.
文献[1]引入一类具有广泛应用前景的随机过程-Markov骨架过程。借助Markov骨架过程的方法研究GI/G/1单重休假服务系统队长,及t时刻到达顾客等待时间的瞬时概率分布。 相似文献
158.
Synthesis of Bioactive and Porous Organic-Inorganic Hybrids for Biomedical Applications 总被引:2,自引:0,他引:2
Kanji Tsuru Satoshi Hayakawa Akiyoshi Osaka 《Journal of Sol-Gel Science and Technology》2004,32(1-3):201-205
Bioactivity has been exhibited by a limited range of ceramics since the invention of Bioglass®. Recently, some bioactive polymeric organic-inorganic hybrids were introduced, including not only organically modified silicates (Ormosils) synthesized from polydimethylsiloxane (PDMS) and tetraethoxysilane but also those with gelatin and 3-glycidoxypropyl-tremethoxysilane. Preparation of the bulk and porous hybrids and their polymeric structures analyzed by Si NMR spectroscopy were presented. In vitro bioactivity or apatite deposition in a simulated body fluid of the Kokubo recipe were also described for those hybrids. Freeze-drying techniques introduced porosity (up to 90%) and pores extending in a preferred direction. 相似文献
159.
Quantization consists in studying the L
r
-error induced by the approximation of a random vector X by a vector (quantized version) taking a finite number n of values. We investigate this problem for Gaussian random vectors in an infinite dimensional Banach space and in particular, for Gaussian processes. A precise link proved by Fehringer(4) and Dereich et al.
(3) relates lower and upper bounds for small ball probabilities with upper and lower bounds for the quantization error, respectively. We establish a complete relationship by showing that the same holds for the direction from the quantization error to small ball probabilities. This allows us to compute the exact rate of convergence to zero of the minimal L
r
-quantization error from logarithmic small ball asymptotics and vice versa. 相似文献
160.
πNN过程对Gottfried求和规则破坏的贡献 总被引:2,自引:0,他引:2
指出在计算πNN过程对核子结构函数的贡献时,将反冲核子视为物理核子更为合理.对Gottfried求和规则破坏、对质子中海夸克分布u和d不对称u(x)–d(x)等方面的贡献给出了详细的计算,与已有实验进行比较.结果表明π介子交换不是导致这一破坏以及影响核子结构函数的效应的惟一来源. 相似文献