基于实数编码的免疫遗传算法研究

针对标准遗传算法(SGA)搜索效率低、收敛速度慢等缺陷，在免疫遗传算法的基础上提出了基于实数编码的免疫遗传算法(RIGA)。研究表明，RIGA对SGA的改进是有效可行的，显示出稳健的全局优化、计算量少而解的精度高等特点，具有较高的应用价值。     

期货经纪公司保证金的一种确定方法

本文基于马尔可夫链在存储论中的应用，结合Ergodic定理，得到确定期货经纪公司保证金的Ergodic模型，即一个双目标规划问题，然后应用乘积最大化准则，将该模型转化为单目标规划问题来求解。该方法考虑期货经纪公司承担的风险和对投资者的吸引程度，为保证金的确定提供新的思路。     

非完整约束奇异广义力学系统的Poincaré-Cartan积分

对受高阶微商非完整约束并用奇异Lagrange量描述的广义力学系 统，基于广义Apell-Четаев约束条件，并考虑到系统的内在约束，导出了该非完整 约 束奇异广义力学系统的广义Poincaré-Cartan积分不变量. 并证明了该不变量与非完整约束 奇异广义力学系统的广义正则方程等价.     

Predictability and model selection in the context of ARCH models

Most of the methods used in the ARCH literature for selecting the appropriate model are based on evaluating the ability of the models to describe the data. An alternative model selection approach is examined based on the evaluation of the predictability of the models in terms of standardized prediction errors. Copyright © 2005 John Wiley & Sons, Ltd.     

A transform method for linear evolution PDEs on a finite interval

We study initial boundary value problems for linear scalar evolutionpartial differential equations, with spatial derivatives ofarbitrary order, posed on the domain {t > 0, 0 < x <L}. We show that the solution can be expressed as an integralin the complex k-plane. This integral is defined in terms ofan x-transform of the initial condition and a t-transform ofthe boundary conditions. The derivation of this integral representationrelies on the analysis of the global relation, which is an algebraicrelation defined in the complex k-plane coupling all boundaryvalues of the solution. For particular cases, such as the case of periodic boundaryconditions, or the case of boundary value problems for even-orderPDEs, it is possible to obtain directly from the global relationan alternative representation for the solution, in the formof an infinite series. We stress, however, that there existinitial boundary value problems for which the only representationis an integral which cannot be written as an infinite series.An example of such a problem is provided by the linearized versionof the KdV equation. Similarly, in general the solution of odd-orderlinear initial boundary value problems on a finite intervalcannot be expressed in terms of an infinite series.     

NCD系统的数学理论

无索赔折扣系统(No Claim Discount system,简记为NCD系统)是世界各国机动车辆险中广泛采用的一种经验费率厘定机制.本文尝试建立了NCD系统严谨的数学理论, 重点讨论了NCD系统的数学建模和稳态分析.此外,作为本文必要的数学前提,首先在第2节着重探讨了随机矩阵间的随机优序关系,并将所得结论运用至齐次不可约且遍历的马尔科夫链的研究中,这些内容也有其独立的数学上的兴趣.     

线性均衡约束最优化的一个广义投影强次可行方向法

本文讨论带线性均衡约束最优化问题,首先利用摄动技术和一个互补函数将问题等价转化为一般约束最优化问题,然后结合广义投影技术和强次可行方向法思想,建立了问题的一个新算法.算法在迭代过程中保证搜索方向不为零,从而使得每次迭代只需计算一次广义投影.在适当的条件下,证明了算法的全局收敛性,并对算法进行了初步的数值试验.     

二次阳极氧化方法制备有序多孔氧化铝膜

通过二次阳极氧化方法制备多孔氧化铝膜与一次阳极氧化方法制备多孔氧化铝膜孔排布规律性的对比 ,结果发现 ,二次阳极氧化方法制取的多孔氧化铝膜孔排布规律性明显好于一次阳极氧化法制取的多孔膜 .在几个微米范围内 ,孔呈理想的六角排布 .去除一次阳极氧化膜后 ,二次阳极氧化得以在更良好的表面进行 ,制取的氧化铝膜孔规律性和有序度更高 .有序区域的尺寸与晶粒内的亚晶大小有一定关系     

Radiation effect on the 400-nm-thermoluminescence emission of a potassium-rich feldspar

The UV-blue thermoluminescence (TL) emission of exsolved and twinned potassium feldspars is potentially valid to be employed in the field of dating and retrospective dosimetry. This paper reports about the following results: (i) The dose dependence of the 400 nm TL intensity of a K-rich feldspar exhibits an excellent linearity in the range of 50 mGy–8 Gy. (ii) The stability of the TL signal after 6 months of storage, shows an initial rapid decay (ca. 45%) maintaining the stability from 40 days onwards which indicates that the electron population decreases asymptotically by the X-axis and the involved electrons are located in deeper traps at room temperature. The fading process can be fitted to a first-order decay equation of the sort y=y₀+A exp(−x/t). (iii) The tests of thermal stability at different temperatures confirm a continuous trap distribution with progressive changes in the glow curve shape, intensity and temperature position of the maximum peak. According to this behaviour some physical parameters are defined.