On integrability of the extended (3+1)-dimensional Jimbo-Miwa equation

By applying the binary bell polynomial scheme, the bilinear form, Bäcklund Transformations, and lax pairs of an extended (3+1)-dimensional Jimbo-miwa (JM) equation are constructed. Next, periodic wave-type solutions can also be obtained to the extended (3+1)-dimensional JM equation through the three-wave method with the help of maple. Finally, a test function of the sech-function method is utilized to get solitary waves of this study problem. These new results can help us better understand interesting physical phenomena and mechanism.     

基于MFBM模型下带交易费和红利的两值期权定价

假设预期收益率μ,红利率q,波动率σ,无风险利率r均为常数,通过平均自融资和Δ-对冲策略建立了离散时间下带交易费用和红利的两值期权定价模型.利用变量代换和偏微分方程的相关知识进行求解此模型,分别得到了在MFBM模型下带交易费用和红利的现金或无值看涨期权(CONC)和资产或无值看涨期权(AONC)定价公式.并在此基础上,推出了现金或无值看跌期权(CONP)和资产或无值看跌期权(AONP)定价公式.     

反射式液晶空间光调制器电控光束偏转

为获得较大的光束电控偏转范围,使用空间分辨力高达8 m的反射式液晶空间光调制器实现了对入射632 nm激光的电控偏转。利用双光束共焦干涉方法测量了液晶空间光调制器的电控相位延迟特性,最大相移量可达3。根据二元光学理论和器件的电控相位延迟特性,设计了周期台阶相位模式和相应的加载灰度图,以最大衍射效率实现对入射光束的闪耀电控偏转。结果表明:相位模式台阶数为8时,可以实现10 mrad的光束偏转,闪耀级次衍射效率可达46%。利用二元光学的衍射模型对影响衍射效率的关键因素进行了分析,认为器件较低的填充因子和周期台阶模式相位重置点诱导的指向矢回程区是限制光束衍射效率的主要因素。     

Label‐free detection of binary mixtures of proteins using surface‐enhanced Raman scattering

The surface‐enhanced Raman scattering (SERS) spectra of five binary mixtures of proteins were studied, including mixtures of apomyoglobin (apMb) and lysozyme, insulin and lysozyme, Mb and cytochrome c (cyt c), Mb and apoMb, and cyt c and human serum albumin. For mixtures in which both proteins did not contain chromophores, the variations in the intensities of SERS signals with changes in the relative concentration of the two proteins were largely proportional to the relative concentration of the protein mixtures. Similar results were obtained for mixtures in which both the proteins contained chromophores. However, for mixtures in which one protein contained chromophores and the other did not, the SERS intensities of the protein mixtures showed a bell‐shaped variation with changes in the compositions of the mixtures. The present study provides new insights into the application of SERS spectroscopy to label‐free detection in a binary of mixture of proteins. The complexities in both SERS phenomena and protein structures should be considered in the analysis of the SERS spectra of protein mixtures. By monitoring the heme band of a protein containing a heme and the NO₃^– band of a protein without a heme, the simultaneous detection of both proteins in a binary mixture may be possible. It has also been found that the larger the size of the protein, the smaller is the SERS intensity of that protein. Copyright © 2011 John Wiley & Sons, Ltd.     

The properties of ferroelectric compound (S)-(+)-4-(1-methylheptyloxycarbonyl)phenyl 4′-(4-cyanoacetoxybut-1-oxy) biphenyl-4-carboxylate and its ability of an antiferroelectric phase induction in mixtures

Phase transitions and ferroelectric properties of (S)-(+)-4-(1-methylheptyloxycarbonyl)phenyl 4′-(4-cyanoacetoxybut-1-oxy)biphenyl-4-carboxylate will be described in this article. This compound exhibits the synclinic smectic C* phase and it has the ability to induce an antiferroelectric phase in mixtures with the other ferroelectric compounds. New systems with induced antiferroelectric phase and their properties are presented.     

双水平集逼近油藏模型特征的数值模拟方法

本文使用双水平集函数逼近油藏模型特征, 构造出Uzawas 算法进行数值模拟. 对于两相流渗透率的数值求解问题, 可以通过测量油井数据和地震波数据来实现. 将构造出来的带限制的最优化问题使用变异的Lagrange 方法求解. 如果使用双水平集函数逼近渗透率函数, 则需要对Lagrange 函数进行修正, 从而将带限制的最优化问题转化成无限制的最优化问题. 由于双水平集函数的优越性, 进一步构造出最速梯度下降Uzawas 算法和算子分裂格式Uzawas 算法进行求解对应的最优化子问题. 数值算例表明设计的算法是高效的、稳定的.     

Proteus仿真技术与数字电路教学整合的实践

从数字电路课堂教学实践出发,以“异步四位二进制计数器”为例,运用Proteus对其电路进行设计、仿真的方法进行探讨.     

A note on the bichromatic numbers of graphs

For a pair of integers k, l≥0, a graph G is (k, l)‐colorable if its vertices can be partitioned into at most k independent sets and at most l cliques. The bichromatic number χ^b(G) of G is the least integer r such that for all k, l with k+l=r, G is (k, l)‐colorable. The concept of bichromatic numbers simultaneously generalizes the chromatic number χ(G) and the clique covering number θ(G), and is important in studying the speed of hereditary properties and edit distances of graphs. It is easy to see that for every graph G the bichromatic number χ^b(G) is bounded above by χ(G)+θ(G)?1. In this article, we characterize all graphs G for which the upper bound is attained, i.e., χ^b(G)=χ(G)+θ(G)?1. It turns out that all these graphs are cographs and in fact they are the critical graphs with respect to the (k, l)‐colorability of cographs. More specifically, we show that a cograph H is not (k, l)‐colorable if and only if H contains an induced subgraph G with χ(G)=k+1, θ(G)=l+1 and χ^b(G)=k+l+1. © 2010 Wiley Periodicals, Inc. J Graph Theory 65: 263–269, 2010     

空中加油问题

对空中加油问题的前两个问题进行了深入系统的研究,发现并证明了与最优解相关的若干事实,对后续的问题求解具有重要的意义.利用得出的结论,加以推导得出求解rn的递推公式,并由此设计了类似于动态规划的循环递推算法.引入“虚拟基地”和“一次性加油”的概念,通过推导得到rn的上界和下界,得出rn与n的渐进关系是对数关系.最后,又提出将问题转化成为二维平面问题,建立一个二叉树模型,通过求解线性规划得到最优解.