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1.
本文首先提出逆(反)对策这一新问题,给出了数学模型;探讨了“奇门遁甲”预测理论(术)中的数学问题;通过系统分析“专门遁甲”预测过程,可知它的预测过程隐含着一个特殊的逆(反)对策问题;最后指出逆(反)对策问题的广泛存在并给出案例分析.  相似文献   
2.
Recently, molecular imaging has been rapidly developed to studyphysiological and pathological processes in vivo at the cellularand molecular levels. Among molecular imaging modalities, opticalimaging has attracted a major attention for its unique advantages.In this paper, we establish a mathematical framework for multispectralbioluminescence tomography (BLT) that allows simultaneous studiesof multiple optical reporters. We show solution existence, uniquenessand continuous dependence on data as well as the limiting behaviourswhen the regularization parameter approaches zero or when thepenalty parameter approaches infinity. Then, we propose twonumerical schemes for multispectral BLT and derive error estimatesfor the corresponding solutions.  相似文献   
3.
An efficient numerical method is presented for solving the equations of motion for viscous fluids. The equations are discretized on the basis of unstructured finite element meshes and then solved by direct iteration. Advective fluxes are temporarily fixed at each iteration to provide a linearized set of coupled equations which are then also solved by iteration using a fully implicit algebraic multigrid (AMG) scheme. A rapid convergence to machine accuracy is achieved that is almost mesh-independent. The scaling of computing time with mesh size is therefore close to the optimum.  相似文献   
4.
 The results of experimental studies of the adsorption at the solution/air interface from an aqueous mixture: 2,4,6-trimethylphenol–2,4,6-trichlorophenol are presented. The surface properties of the above-mentioned mixture were studied by surface potential and surface tension measurements. These measurements were carried out as a function of the concentration of 2,4,6-trimethylphenol aqueous solution at a constant concentration of 2,4,6-trichlorophenol. Using the results obtained and based on the Gibbs equation, Helmholtz formula and Motomura’s method the relative surface excesses of adsorbed substances, effective dipole moments, surface molar fractions of solutes and miscibility of adsorbed films were determined. Received: 7 November 1997 Accepted: 26 February 1998  相似文献   
5.
Transference numbers of HCl(aq) solutions at 25°C, from 0.01 to 13.6 mol-kg–1(m) have been obtained by measuring the emf of cells with transference using hydrogen gas/platinum electrodes. Good agreement is obtained at concentrations up to 1 m with all previous data, and our results strongly corroborate those of King and Spiro over the 2–8m concentration range. The transference numbers of the hydronium ion fit the empirical equation, H HCl = 0.821 + 0.0457m 1/2 – 2.476×10–2m – 1.90×10–4 m 2 – 1.45×10–5 m 3 the maximum deviation in T H HCl being 0.003.  相似文献   
6.
A Note on Casoratian Solutions to Two-Dimensional Toda Lattice   总被引:2,自引:0,他引:2  
In this short paper we generalize the conditions that Casoratian entries satisfy for the two-dlmenslonal Toda lattice. Although we finally conclude that our generalization is trivial in some sense for getting new solutions, our discussion is still helpful for the study of Wronskian technique.  相似文献   
7.
采用高光谱技术对复杂混合溶液进行检测分析,同时利用被测物质的吸光度和散射特性信息以提高光谱的信噪比。实验设计了高光谱采集装置,采集生物组织模拟液(Intralipid-10%)的漫反射高光谱图像,并用Monte Carlo方法和漫射近似理论对其进行了正向和反向推导,获得了632nm波长下,Intralipid-10%吸收系数为0.002 0cm-1,与标准参数相对误差为11.1%;约化散射系数为63.35cm-1,与标准参数相对误差为6.49%,基本符合标准参数的误差范围,验证了该高光谱检测系统的准确性。还利用该高光谱系统对不同厂家出品的牛奶、果汁等样本进行了高光谱采集,得到不同样本间差异较传统二维光谱更为明显的结果,充分证明了高光谱方法在复杂混合溶液成分分析中具有很强的可行性。  相似文献   
8.
In this letter, we study discretized mKdV lattice equation by using a new generalized ansatz. As a result,many explicit rational exact solutions, including some new solitary wave solutions, are obtained by symbolic computation code Maple.  相似文献   
9.
系统研究了表面润湿法合成β沸石的体系中,干晶种、润湿态晶种、异晶晶种(Y沸石、ZSM 5沸石)以及碱处理β沸石晶种在此晶化体系中的作用.采用β沸石产品及异晶作晶种时,可使产品的相对结晶度稍有提高,但对沸石微晶核的结构导向作用不明显.经浓碱液处理20min后的β沸石产品(碱处理晶种)作晶种引入晶化体系后,可以显著提高产品的相对结晶度,降低模板剂的用量,缩短晶化诱导期,成为表面润湿法合成β沸石体系的有效晶种形式.  相似文献   
10.
We have experimentally studied for the first time the effect of photoinduced rotation of the plane of polarization for pulsed laser radiation in solutions of C70 fullerene in organic solvents and their mixtures. We have shown that the effect is observed for elliptical polarization of the laser radiation and is absent for linear polarization. We present the results of a study of the nonlinear optical characteristics of the C70 solutions. We discuss the physical mechanisms by which nonlinear gyrotropy is induced in solutions. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 76, No. 1, pp. 93–99, January–February, 2009.  相似文献   
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