转盘上单机排序问题的可解情形

文献[1]中证明,即使只有一台加工机器,带有转盘的流水作业问题的加工全长问题 T1也是强 NP 困难的。本文讨论问题 T1的几个多项式时间的可解情形。     

Instability in patchworks of child care when moving from welfare to work

We use longitudinal, qualitative interview data collected from 38 initially welfare‐reliant women in Cleveland, Ohio to examine the factors driving instability in child‐care arrangements when women transitioned from welfare to work. Grounded theory analysis revealed that decisions about care were circumscribed by scarce social and economic resources, women went to extraordinary lengths to patch together arrangements that typically involved multiple providers, relative care was central to patchworks of care, and patchworks of child care were often highly unstable. These complex arrangements and their instability were influenced by mothers’ desires to find the most suitable arrangements for their children within resource and job constraints, dissatisfaction with providers, difficulties accessing subsidies, and changes in provider availability. Findings suggest that policymakers must consider instability in patchworks of multiple child‐care providers as they consider alternatives for meeting low‐wage working women's and children's needs for safe, affordable, accessible, and enriching nonmaternal child care.     

18T自行车单级飞轮飞壳的冷滚轧成形

对单级飞轮飞壳冷滚轧成形原理及轧辊的设计分析,介绍了轧辊结构、成形工艺过程,夹具形式和轧机参数等.     

Book Reviews

Books reviewed:
Anthony, Atkinson & Marco, Riani, Robust Diagnostic Regression Analysis
N., Balakrishnan & C.R., Rao, Order Statistics: Theory & Methods. Handbook of Statistics, Volume 16
N., Balakrishnan & C.R., Rao, Order Statistics: Applications. Handbook of Statistics, Volume 17
C.R., Rao & G.J., Székely, Statistics for the 21st Century: Methodologies for Applications of the Future
D.A., Nolan & T.P., Speed, Stat Labs: Mathematical Statistics Through Applications
W.N., Venables & B.D., Ripley, S Programming
Peter W.M., John, Statistical Design and Analysis of Experiments     

整体波场延拓法基准面校正与常规方法对比

消除近地表对地震波场所造成的影响，常规的解决方法是静校正和波动方程基准面校正。当勘探区域近地表出现较大的地形起伏或速度横向变化时，波动方程基准面校正则成为唯一有效的选择。传统波动方程基准面校正在实现过程中需要在双域对炮点、检波点分别进行延拓成像。为此，作者曾提出一种新的近地表问题解决方法——整体波场延拓法基准面校正(WEDD)。本文对WEDD方法和常规基准面校正方法在理论上进行了对比分析，并通过数值模拟讨论了各基准面校正方法的优缺点和适用范围。     

BAB算法中集成CPT求解job-shop调度问题

CSP(constraintsatisfactoryproblem)的优势在于能够处理复杂约束,获得一个满足约束的解,但难以保证解的质量.OR(operationresearch)的优点是获得最优解或近优解,但它求解复杂约束的优化问题非常困难.CPT(constraintpropagationtechnique)是CSP的主要搜索技术,BAB(branch_and_bound)是OR常用的优化算法.提出了一种将CPT集成于BAB中的混合算法,从一个新的角度解决具有一般性与挑战性的job shop调度问题.其主要特点是,通过在BAB算法中嵌入动态可调的时间窗口约束和加强一致性CPT搜索方法,融合BAB的优化能力和CPT处理复杂约束的能力,提高BAB的优化性能及实际应用能力.实验结果令人满意,证明了算法的有效性.     

三音节合成词的结构类型及层次

三音节的三语素合成词在汉语的词汇系统中占有较为重要的一席之地 ,不应该受到忽略。其结构方式远比双音节的双语素合成词复杂多样 ,大大超出一般词汇书上所认定的几种结构形式。可分作两个大类 :复合型与缀加型。复合型中以偏正形式为绝对优势 ,偏正式中又以“定+中”型为优势 ,体现出汉语三音节合成词强烈的名词化倾向。由于偏正式在三音节中的特殊地位 ,主要探讨这一类型的各种结构方式及其性质与组合关系。     

论我国政党制度在世界政党制度中的归类

我国的政党制度是中国共产党领导的多党合作制,不能将它归类于"一党制"或"多党制".我国政党制度可以称之为"一党领导多党合作制",在活动方式上与"一党制"有两点显著的区别.这一制度与前苏联及几个原东欧社会主义国家的"一党领导制"不同,而与另几个原东欧社会主义国家的政党制度基本相同,但小有差别.无论是从"一党领导"角度还是从"多党合作"角度看,我国的政党制度既具有独创性又具有普遍性,它的产生有其深刻的社会历史根源.应该在改革中坚持和进一步完善.     

Approximation Algorithms in Batch Processing

A polynomial approximation scheme for minimizing makespan in a batch processing system under dynamic job arrivals is presented. A lower bound of on the competitive ratio of any on-line algorithm is proved. This is matched by an on-line algorithm for the special case of unbounded machine capacity.     

Ordinal On-Line Scheduling for Maximizing the Minimum Machine Completion Time

This paper considers the on-line problem of scheduling nonpreemptively n independent jobs on m > 1 identical and parallel machines with the objective to maximize the minimum machine completion time. It is assumed that the values of the processing times are unknown but the order of the jobs by their processing times is known in advance. We are asked to decide the assignment of all the jobs to some machines at time zero by utilizing only ordinal data rather than the actual magnitudes of jobs. Algorithms to slove the problem are called ordinal algorithms. In this paper, we give lower bounds and ordinal algorithms. We first propose an algorithm MIN which is at most -competitive for any m machine case, while the lower bound is _i=1 ^m 1/i. Both are on the order of (ln m). Furthermore, for m = 3, we present an optimal algorithm.