Race to idle or not: balancing the memory sleep time with DVS for energy minimization

Reducing energy consumption is a critical problem in most of the computing systems today. Among all the computing system components, processor and memory are two significant energy consumers. Dynamic voltage scaling is typically applied to reduce processor energy while sleep mode is usually injected to trim memory’s leakage energy. However, in the memory architecture with multiple cores sharing memory, in order to optimize the system-wide energy, these two classic techniques are difficult to be directly combined due to the complicated interactions. In this work, we explore the coordination of the multiple cores and the memory, and present systematic analysis for minimizing the system-wide energy based on different system models and task models. For tasks with common release time, optimal schemes are presented for the systems both with and without considering the static power of the cores. For agreeable deadline tasks, different dynamic programming-based optimal solutions are proposed for negligible and non-negligible static power of cores. For the general task model, this paper proposes a heuristic online algorithm. Furthermore, the scheme is extended to handle the problem when the transition overhead between the active and sleep modes is considered. The optimality of the proposed schemes for common release time and agreeable deadline tasks are proved. The validity of the proposed heuristic scheme is evaluated through experiments. Experimental results confirm the superiority of the heuristic scheme in terms of the energy saving improvement compared to the most related existing work.     

Severity of illness: red herring or horse of different color? Part 2.

In this continuation of his article, the author defines severity and acuity of illness and discusses approaches to the measurement of the two factors. He provides some background on severity of illness measures that are in current use and prepares for a discussion of the uses of these measures.     

Severity of illness: red herring or horse of different color? Part 3.

In this final article in a three-part series, the author discusses the various issues that surround the use of severity-of-illness measures. Particular attention is paid to the use of such measures to assess the performance of providers in the area of quality.     

All or nothing: International coalitions responding to competing pressures in challenges to IP rights

Foreign subsidiaries face ‘institutional duality’ from competing parent-firm and host-country conformity pressures. However, international coalitions of firms experience pressures to conform from multiple parents, resulting in ‘institutional multiplicity.’ We argue that coalition members bargain and satisfice to agree upon goals and responses to external pressures. As institutional multiplicity increases, coalition responses are increasingly framed around simple threshold-type goals all members can agree upon. We test this idea in the context of international coalitions challenging biotechnology and organic chemistry patents of competitors in the United States Patent and Trademark Office's Patent Trial and Appeals Board. Our analysis includes 946 observations, and finds that larger coalitions with greater variance in member home-country patent enforcement institutions are more likely to pursue strategies that have a simple performance goal all members can agree upon: having a competitor's patent invalidated instead of a settlement. This relationship is further enhanced when coalition members have diverse levels of strategic interest, captured by variance in portions of coalition members' overall patent portfolios belonging to the same patent family as the disputed patent.     

Awareness of dying: an experience of Chinese patients with terminal cancer

Despite the effort to provide an alternate way to dying, there seems to be little effort to examine the real situation of hospice care. For example, the patients' desired outcomes are seldom addressed. It is recently that studies began to investigate the features of "good death." However, work in eastern cultures, such as Chinese, remains scarce. The purpose of this study is to gain an understanding of what it means to die a "good death" from the perspective of Chinese patients. Thirty-three Chinese hospice patients with terminal cancer were interviewed. Grounded in the analysis of qualitative data, seven elements that contribute to dying a good death emerged. Awareness of dying was identified as the foremost essential element of a good death. From the findings of this study, most respondents considered receiving a diagnosis of cancer as one of the significant points of psychological distress in the course of their illness. Half of the patients openly talked about their cancers and more than half of them discussed various issues related to death. That means, about one-third of the respondents talked about death and cancer with openness. These preliminary findings may reflect the progress of hospice work in Hong Kong. Meanwhile, 13 respondents did not mention the word "death" and 16 of them did not mention that they had cancer. They talked about their illness and future using the expressions that they preferred. It is important that health care professionals also respect people who show awareness of dying as much as those who do not present clear evidence of this awareness. Both groups of people can have a positive experience when they die.     

“共生”关系下的控制权防御机制设计———以“万科与宝能系之争”为例

搭建了公司控制权防御机制设计的理论框架,并以万科抵御宝能敌意收购事件为例对理论框架进行了验证。研究结果表明: 1) 在“共生”关系下,公司特质和收购路径特征分别决定了事前 (预防型) 和事中 (主动型) 控制权防御机制的设计; 2) 为了缓解控制权防御机制过度保护管理层的现象,设计维系“共生”关系的制衡机制必不可少; 3) 控制权防御机制设计受制度环境的制约,并随着制度境、公司特质和收购路径的变化动态演进。突破了既有的公司控制权防御机制研究的分析框架,能为我国上市公司设计控制权防御机制提供一定的参考价值。     

Clustering with or without the approximation

We study algorithms for clustering data that were recently proposed by Balcan et al. (SODA’09: 19th Annual ACM-SIAM Symposium on Discrete Algorithms, pp. 1068–1077, 2009a) and that have already given rise to several follow-up papers. The input for the clustering problem consists of points in a metric space and a number k, specifying the desired number of clusters. The algorithms find a clustering that is provably close to a target clustering, provided that the instance has the “(1+α,ε)-property”, which means that the instance is such that all solutions to the k-median problem for which the objective value is at most (1+α) times the optimal objective value correspond to clusterings that misclassify at most an ε fraction of the points with respect to the target clustering. We investigate the theoretical and practical implications of their results. Our main contributions are as follows. First, we show that instances that have the (1+α,ε)-property and for which, additionally, the clusters in the target clustering are large, are easier than general instances: the algorithm proposed in Balcan et al. (SODA’09: 19th Annual ACM-SIAM Symposium on Discrete Algorithms, pp. 1068–1077, 2009a) is a constant factor approximation algorithm with an approximation guarantee that is better than the known hardness of approximation for general instances. Further, we show that it is NP-hard to check if an instance satisfies the (1+α,ε)-property for a given (α,ε); the algorithms in Balcan et al. (SODA’09: 19th Annual ACM-SIAM Symposium on Discrete Algorithms, pp. 1068–1077, 2009a) need such α and ε as input parameters, however. We propose ways to use their algorithms even if we do not know values of α and ε for which the assumption holds. Finally, we implement these methods and other popular methods, and test them on real world data sets. We find that on these data sets there are no α and ε so that the dataset has both (1+α,ε)-property and sufficiently large clusters in the target solution. For the general case where there are no assumptions about the cluster sizes, we show that on our data sets the performance guarantee proved by Balcan et a. (SODA’09: 19th Annual ACM-SIAM Symposium on Discrete Algorithms, pp. 1068–1077, 2009a) is meaningless for the values of α,ε for which the data set has the (1+α,ε)-property. The algorithm nonetheless gives reasonable results, although it is outperformed by other methods.     

我国上市公司配股前后业绩变化及其影响因素的实证研究

本文首次系统考查了我国上市公司配股融资后的业绩表现及其影响因素。实证研究表明,我国上市公司配股融资后业绩出现显著的下降,和没有配股的配比公司相比,配股公司的业绩要好于配比公司,但在配股后第3年,开始逊色于配比公司,并且,公司配股后业绩的下降幅度大于配比公司。本文首次发现,自由现金流假说能很好解释我国上市公司配股后长期业绩下滑的影响因素,公司配股前的自由现金流量越多,公司配股后的业绩下降得越快,公司的股权集中度低与投资水平低的上市公司,配股后业绩下降得越快。另外,公司的成长性越高,资产规模越大,公司配股后业绩下降的更快。     

"Almost the copy of my child that's dead": Shakespeare and the loss of Hamnet

This article emphasizes the importance of studies which look at changes and similarities in mourning over time. It argues that relevant evidence can come from creative fiction as well as from other sources, provided that this is analyzed rigorously in terms of structures and patterns. As an illustration of this approach, it examines the evidence in recurring features of Shakespeare's plays that his writing was deeply and lastingly affected by the death of his only son Hamnet, a twin, at the age of 11, and identifies five motifs which support this interpretation: the resurrected child or sibling; androgynous and twin-like figures; a growing emphasis on father-daughter relationships; paternal guilt; family division and reunion. The article suggests that this approach could be applied to other instances where a body of creative writing shows traces of overt or buried grief.     

Through the touch of god: child death and spiritual sustenance in a Hutterian colony

Nestled in more than 5,000 acres of farmland in rural South Dakota, one Hutterian colony flourishes with more than 23 families and a population of 115 people. Very little is known about the ways in which Hutterites experience traumatic infant and child death on the colony. No research studies to date have explored this topic. This is an ethnographic study that utilized extended observations of the group and both individual and group interviewing in order to create a cultural portrait specifically focusing on Hutterites experiencing traumatic child death. Observations were organized into five thematic categories: 1) details of the actual death experience; 2) emotional and physical reactions to the loss; 3) familial and communal response; 4) coping and rituals; and 5) spirituality. The role of communal mourning, ritualization, and spirituality in creating a healing milieu for bereaved families is discussed.     

Limitations of working memory capacity: The cognitive and social consequences

This paper aimed to explore, from the perspective of cognitive psychology, the natural limitations of human cognition that determine our capabilities to deal with information overflow. These limitations are related mainly to the working memory system. This system is conceived to be composed of the storage components, which are responsible for active maintenance, and executive control that supervises the storage units. People differ in their working memory capacities, and because virtually every complex cognitive activity requires the temporal availability of a certain amount of cognitive representations, these differences are predictive of many outcomes. In the area of ‘cold’ cognition, these outcomes include intelligence and verbal reasoning, multitasking, language comprehension and verbal fluency, whereas in the area of ‘hot’ cognition, they include mentalising, stereotyping and self-control. Natural limitations in working memory capacity may be overcome (to some extent) through the training of working memory skills or the application of processing strategies (e.g. task simplification, using external environment as in situated or distributed cognition, changing a code of mental representation).     

Exemplar or matching: modeling DCJ problems with unequal content genome data

The edit distance under the DCJ model can be computed in linear time for genomes with equal content or with Indels. But it becomes NP-Hard in the presence of duplications, a problem largely unsolved especially when Indels (i.e., insertions and deletions) are considered. In this paper, we compare two mainstream methods to deal with duplications and associate them with Indels: one by deletion, namely DCJ-Indel-Exemplar distance; versus the other by gene matching, namely DCJ-Indel-Matching distance. We design branch-and-bound algorithms with set of optimization methods to compute exact distances for both. Furthermore, median problems are discussed in alignment with both of these distance methods, which are to find a median genome that minimizes distances between itself and three given genomes. Lin–Kernighan heuristic is leveraged and powered up by sub-graph decomposition and search space reduction technologies to handle median computation. A wide range of experiments are conducted on synthetic data sets and real data sets to exhibit pros and cons of these two distance metrics per se, as well as putting them in the median computation scenario.     

不打不成器:挖掘辱虐管理的正效应、负效应和净效应

辱虐管理一直是负面组织行为的研究热点,近年呈现一些新趋势,特别是在崇尚“不打不成器”的本土情境下,挑战视之为“绝对恶魔”的呼声渐起。理论创始人Tepper也呼吁进行更多的研究来比较与整合其正面和负面效应。摒弃已有研究忽视辱虐管理主观目的性的研究惯例,从概念本源出发,整合感知控制理论与有限控制理论双重线索,探讨了辱虐管理与下属绩效的倒U型关系及其成因。453份配对样本的Fieller法和J-N法检验结果支持了倒U型假设,并揭示辱虐管理对下属自我努力有凹型影响,较大程度上促进下属的纠偏努力,对自我损耗有凸型影响,加剧损耗;正负效应的叠加导致倒U型净效应出现。研究结果有助于深化辱虐管理影响机制研究,也有助于丰富和拓展非线性方法研究。