Local Encoding Transformations for Optimizing OBDD-Representations of Finite State Machines

Ordered binary decision diagrams are the state-of-the-art representation of switching functions. In order to keep the sizes of OBDDs tractable, heuristics and dynamic reordering algorithms are applied to optimize the underlying variable order. When finite state machines are represented by OBDDs the state encoding can be used as an additional optimization parameter. In this paper, we analyze local encoding transformations which can be applied dynamically. First, we investigate the potential of re-encoding techniques. We then propose the use of an XOR-transformation and show why this transformation is most suitable among the set of all encoding transformations. The presented theoretical framework establishes a new optimization technique for OBDDs.     

求补舍入并行和位长自适应整数转浮点数电路设计

提出了一种实现整数转浮点数的新的设计方法 ,并且对方法的正确性给予了证明 .采用这种设计方法 ,实现了求补和舍入的合并并行 ,使关键路径的延时比常规的电路设计方案减少了 15级门 ,同时降低了电路规模 .关键路径延时的减小 ,使这一转换可以在单周期内完成 .另外 ,该方法实现了位长自适应 ,只需花费很少的电路规模和延时实现控制 ,就可以适应长整型、整型到单、双精度浮点数的转换 ,增强了电路功能 .这一设计方法同样适用于其逆转换 .该转换模块采用 Fujitsu CE71库设计 ,在 10 0 MHz主频下经仿真验证 ,结果正确 ,已经应用到实际工程中 .     

Response to ‘Comments on: A cohesion measure for object‐oriented classes’

Indicating that CBMC does not satisfy the monotonic property in terms of the number of interactions, Xu and Zhou proposed an augmented definition of CBMC by adopting cut set instead of glue methods. The augmented CBMC clearly satisfies the monotonic property. However, CBMC is designed to overcome the problem with respect to the number of interactions and, therefore, focuses on the interaction pattern, especially, member connectivity. Consequently, it does not make sense to mention the monotonic property of CBMC with respect to interaction number. Moreover, the notion of glue methods allows several interpretations on the design quality of a class. However, that meaningful interpretation is not possible for the augmented definition due to the removal of the notion of glue methods. Copyright © 2001 John Wiley & Sons, Ltd.     

A computational method for simulating growth patterns in unicell propagation

The modelling of natural phenomena through the use of computer-generated graphics has attracted much interest recently. It is believed that such methods will lead to new breakthroughs in understanding nature. One of the most popular methods used is the cell automata method, where cells are made to propagate and form cellular patterns according to certain predefined rules. Although much of the work in this area is for recreational purposes, as in the Game of Life, there can be more serious aspects to it. One of these is in the use of such methods to predict and simulate the growth behaviour of cell clusters in real-life situations. In this study, an attempt is made to formalise certain rules for modelling the growth characteristics of unicell populations. The methodology proposed models three fundamental factors: first, the generic propagational characteristics of a cell; second, the effect of adverse factors to growth; and, third, the effect of spatial constraints. The first two factors, relating to the population of a cell colony, can be modelled mathematically; the third factor determines the visual appearance of the cell colony. Patterns resulting from some computational simulations are presented and discussed.     

缫丝排序算法

文中提出一种改进的排序算法,弥补了快速排序在大规模下堆栈低效及合并排序在小规模下优势不明显的问题.算法扩展了合并排序思想,从一种特殊的蚕茧缫丝工艺得到启发,使用2～6个滚轴分离待排序列中的有序片段,在滚轴始末端扩展新数据,从而达到在合并操作前增加有序子序列长度的目的.理论推导表明,缫丝排序中的基本操作数量较合并排序减少4.75N,相当于将待排序列缩小至原有规模的1/4;效率测试实验表明,缫丝排序在各种规模下均能获得相比最快经典排序算法10％～15％的稳定优势,相比前人的改进排序算法具备相当的互补性,并能有效降低排序库函数自适应选择算法的实现复杂度.     

基于概率的有序信息系统

若信息系统中所有的条件属性都是偏好有序的,则称此信息系统为有序信息系统。首先,分析了区间值有序信息系统没有蕴含属性值区间上的概率分布信息的缺点,建立了一种基于概率的有序信息系统。然后,在这种信息系统上,研究了关于单调偏好有序属性和非单调偏好有序属性的二元偏好关系,建立了一种基于概率的优势关系,定义了基于这种优势关系的粗糙集模型。最后研究了基于概率的有序决策表及其决策规则。     

正数和与积的对偶不等式

给出了在个数相同的两组正数之积相等的情形下,判定这两组正数之和大小的一个充分条件,由此得出了正数和最大值存在的链式条件．应用这一链式条件解决了将,nl个正数分成等个数的n个数组后,每组之积的和与每组之和的积的最值问题．对于正数积的最小值问题,证明了与正数和最大值类似的结果,且相应的定理之间互为对偶定理．     

Quantum analysis of measurement results

It is shown that a stochastic matrix operator (quantum measurement matrix) may be considered in some cases as a density matrix. Results of measurements in the form of figure numbers, interconnected with a matrix of quantum measurements, are similar to quantum observable quantities determined in quantum statistical theory. __________ Translated from Izmeritel’naya Tekhnika, No. 12, pp. 3–8, December, 2006.     

Omnibus Hypothesis Testing in Dominance-Based Ordinal Multiple Regression.

Often quantitative data in the social sciences have only ordinal justification. Problems of interpretation can arise when least squares multiple regression (LSMR) is used with ordinal data. Two ordinal alternatives are discussed, dominance-based ordinal multiple regression (DOMR) and proportional odds multiple regression. The Q2 statistic is introduced for testing the omnibus null hypothesis in DOMR. A simulation study is discussed that examines the actual Type I error rate and power of Q2 in comparison to the LSMR omnibus F test under normality and non-normality. Results suggest that Q2 has favorable sampling properties as long as the sample size-to-predictors ratio is not too small, and Q2 can be a good alternative to the omnibus F test when the response variable is non-normal. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Barrier Trees on Poset-Valued Landscapes

Fitness landscapes have proved to be a valuable concept in evolutionary biology, combinatorial optimization, and the physics of disordered systems. Usually, a fitness landscape is considered as a mapping from a configuration space equipped with some notion of adjacency, nearness, distance, or accessibility, into the real numbers. In the context of multi-objective optimization problems this concept can be extended to poset-valued landscapes. In a geometric analysis of such a structure, local Pareto points take on the role of local minima. We show that the notion of saddle points, barriers, and basins can be extended to the poset-valued case in a meaningful way and describe an algorithm that efficiently extracts these features from an exhaustive enumeration of a given generalized landscape.