超效率DEA模型的区间扩展

将一种改进的DEA模型-超效率DEA(SE-DEA)模型[1]拓展到区间投入产出情形,得到区间SE-DEA模型。定义了一种反映决策者满意度的区间数序关系。当决策者给定一满意度水平,将区间SE-DEA中的区间不等式约束转化为确定型约束。研究了该满意度水平的另一层含义,即决策者对除被评价决策单元外的其它决策单元的偏好程度,据此将区间SE-DEA中的区间等式约束和区间目标函数转化为确定型。最终将区间SE-DEA转化为某一满意度水平下的确定型SE-DEA,并进行求解。最后将文中方法应用于天津市某4家科研所的效率预测问题之中。     

Computational Comparison Studies of Quadratic Assignment Like Formulations for the In Silico Sequence Selection Problem in De Novo Protein Design

In this paper an O(n²) mathematical formulation for in silico sequence selection in de novo protein design proposed by Klepeis et al. (2003, 2004), in which the number of additional variables and linear constraints scales with the square of the number of binary variables, is compared to three O(n) formulations. It is found that the O(n²) formulation is superior to the O(n) formulations on most sequence search spaces. The superiority of the O(n²) formulation is due to the reformulation linearization techniques (RLTs), since the O(n²) formulation without RLTs is found to be computationally less efficient than the O(n) formulations. In addition, new algorithmic enhancing components of RLTs with inequality constraints, triangle inequalities, and Dead-End Elimination (DEE) type preprocessing are added to the O(n²) formulation. The current best O(n²) formulation, which is the original formulation from Klepeis et al. (2003, 2004) plus DEE type preprocessing, is proposed for in silico sequence search. For a test problem with a search space of 3.4×10⁴⁵ sequences, this new improved model is able to reduce the required CPU time by 67%.     

Mixtures of concentrated multivariate sine distributions with applications to bioinformatics

Motivated by examples in protein bioinformatics, we study a mixture model of multivariate angular distributions. The distribution treated here (multivariate sine distribution) is a multivariate extension of the well-known von Mises distribution on the circle. The density of the sine distribution has an intractable normalizing constant and here we propose to replace it in the concentrated case by a simple approximation. We study the EM algorithm for this distribution and apply it to a practical example from protein bioinformatics.     

试谈蛋白质对体育运动的影响

体育运动中,肌肉的收缩和构弛是靠肌肉中蛋白质的分子的活动来实现的。蛋白质的供给量取决于年龄、体重、运动强度和生理状况等因素。运动员的蛋白质摄取量随运动强度的不同而改变。研究表明,学生的早餐主要应以蛋白质为主,或在上午10点钟左右增加一次膳食。     

网络文学刍议

网络文学与常规文学的不同之处在于创作的非法则性和作者的平民身份。目前的网络文学面临的问题有：写作心态和写作立场问题，“超文本性”真正实现的问题，以及如何避免被常规文学同化的问题。     

核糖体失活蛋白及研究进展

核糖体失活蛋白是一类广泛存在于高等植物体内的能抑制核糖体功能的植物毒蛋白 ,分单链和双链两种 ,除了能使蛋白质合成受阻外 ,还具有抗生育、抗肿瘤和抗艾滋病病毒等诸多生物活性     

广西野生稻资源品质研究

本文报道了广西二种野生稻资源外观米质与粗蛋白含量的鉴定结果,分析了这二个性状的关系。为人们提供了一批可利用的外观米质优良及粗蛋白含量高的二种野生稻资源的目录,它们是生物工程研究和水稻优质育种的宝贵材料。     

平面波垂直入射浸渍吸收剂蜂窝的反射特性(英文)

提出一个数值方法,计算当平面波垂直于蜂窝板入射时浸渍吸收剂的蜂窝的反射系数。在引入蜂窝壁表面阻抗后,借助于周期格林函数对无限大蜂窝表面建立了电场积分方程,用矩量法求解未知的表面电流。在8~12 GHz频段内,得到的不同蜂窝高度、不同吸收剂和不同浸渍厚度的数值结果表明,所提出的方法是高效的,可用于蜂窝制备和吸波结构的工作中。     

Bayesian alignment of proteins via Delaunay tetrahedralization

An active area of research in bioinformatics is finding structural similarity of proteins by alignment. Among many methods, the popular one is to find the similarity based on statistical features. This method involves gathering information from the complex biomolecule structure and obtaining the best alignment by maximizing the number of matched features. In this paper, after reviewing statistical models for matching the structural biomolecule, it is shown that local alignment based on the Delaunay tetrahedralization (DT) can be used for Bayesian alignment of proteins. In this method, we use DT to add a priori structural information of protein in the Bayesian methodology. We demonstrate that this method shows advantages over competing methods in achieving a global alignment of proteins, accelerating the convergence rate and improving the parameter estimates.     

Multi-character survery using randomized response technique

In the present paper, we have consisdered the situation of multi–character survey where the study variables, beside being poorly correlated with the selection probabilities are also sensitive in nature. Randomized Response technique (RRT) proposed by Chaudhuri and Adhikary (1990) is used to elicit the information on the sensitive character. The empirical study carried out shows the relative efficiency of the transformation suggested by Basnel and Singh (1985) over the transformations suggested by Rao (1966) and Amahia et al.(1989) under a super population model.