Fossil treasure house for exploring the Cambrian explosion

<正>The abrupt appearance of animal phyla in the fossil record at the beginning of the Cambrian period,known as the Cambrian explosion[1],is the most dramatic chapter in the annals of animal evolutionary history.As early as 1909,the great paleontologist Charles D.Walcot discovered the Burgess Shale fauna in the Middle Cambrian Burgess Shale of     

A procedure for comparing passive,active, and semi-active approaches to vibration isolation

A procedure is developed which uses bond graph modeling and a digital computer to determine if semi-active control can provide a suitable performance in an application where totally active control is considered. The application areas principally addressed are those in which the disturbance inputs to the system are of zero mean, i.e. shock and vibration control.The procedure is developed through examples and then generalized to systems of high order and large complexity. The procedure consists basically of designing a control strategy suitable for totally active control and then enforcing a passivity constraint on the actuating device. Experience has shown that semi-active control approaches that of totally active control in most vibration isolation applications.     

数字电路测试压缩方法研究（英文）

测试压缩可以在没有故障覆盖率损失的情况下，极大地降低测试时间和测试数据量，弥补了测试设备和芯片制造能力提升之间的差距，受到学术界和工业界的广泛关注。测试数据分为测试激励和测试响应两种，测试压缩也对应分为测试激励压缩和测试响应压缩两个方面。本文针对这两方面分别展开了研究。本文的主要贡献包含：1. 提出了一种Variable-Tail编码。Variable-Tail是一种变长－变长的编码，对于X位密度比较高的测试向量能够取得更高的测试压缩率。实验数据表明，如结合测试向量排序算法，则使用Variable-Tail编码可以取得很接近于编码压缩理论上界的压缩效果（平均差距在1.26%左右），同时还可以减少20％的测试功耗。2. 提出了一种并行芯核外壳设计方法。研究发现了测试向量中存在着扫描切片重叠和部分重叠现象。当多个扫描切片重叠时，它们仅需要装载一次，这样就可以大大减少测试时间和测试数据量。实验结果表明，使用并行外壳设计，测试时间可以减少到原来的2/3，测试功耗可以减少到原来的1/15。 3．提出了3X测试压缩结构。3X测试压缩结构包含了三个主要技术：X-Config 激励压缩、X-Balance测试产生和X-Tolerant响应压缩。 X-Config激励压缩提出了一个周期可重构的MUX网络。X-Balance 测试产生综合考虑了动态压缩、测试数据压缩和扫描设计等因素，产生测试向量。它使用了回溯消除算法和基于确定位概率密度的扫描链设计算法，减少测试向量体积。X-Tolerant 响应压缩提出了一种单输出的基于卷积编码的压缩电路。该压缩电路只需要一个数据，因此总能保证最大的压缩率。同时为了提高对X位的容忍能力，还提出了一个多权重的基本校验矩阵生成算法。     

Narrative approaches to the transfer of organisational knowledge

Narratives, or stories, have been identified as one of the ways in which knowledge might be transferred, shared or exchanged in organisational settings. Beyond their identification, little consideration has been given to the ways in which narrative approaches can increase our understanding of the creation and dissemination of knowledge in organisations. This paper reflects upon some of the ways in which narrative approaches might contribute towards a better understanding of organisational knowledge management. It contributes to the debate on the nature and significance of the contextual features of organisational knowledge, particularly the role of tacit knowledge, and identifies some of the distinctions between formal and informal knowledge transfer mechanisms, which operate (with or without effective management) within organisations.     

A review of ranking approaches for semantic search on Web

With ever increasing information being available to the end users, search engines have become the most powerful tools for obtaining useful information scattered on the Web. However, it is very common that even most renowned search engines return result sets with not so useful pages to the user. Research on semantic search aims to improve traditional information search and retrieval methods where the basic relevance criteria rely primarily on the presence of query keywords within the returned pages. This work is an attempt to explore different relevancy ranking approaches based on semantics which are considered appropriate for the retrieval of relevant information. In this paper, various pilot projects and their corresponding outcomes have been investigated based on methodologies adopted and their most distinctive characteristics towards ranking. An overview of selected approaches and their comparison by means of the classification criteria has been presented. With the help of this comparison, some common concepts and outstanding features have been identified.     

New approaches to stability analysis for time-varying delay systems

In this paper, two new estimation approaches namely delay-dependent-matrix-based (DDMB) reciprocally convex inequality approach and DDMB estimation approach, are introduced for stability analysis of time-varying delay systems. Different from existing estimation techniques with constant matrices, the estimation approaches are with delay-dependent matrices, which can employ more free matrices and utilize more information of both time delay and its derivative. Based on the estimation approaches, less conservative stability criteria with lower computational complexity are derived in the form of linear matrix inequalities (LMIs). Finally, two numerical examples are given to illustrate the advantages of the proposed methods.     

高校大学生安全教育格局模式创新路径的实践与探讨

从大学生安全教育工作实践经验的视角提出安全教育存在的问题,探讨高校大学生安全教育格局模式的创新路径,通过构建课内外安全教育格局延扩大学生安全教育教学时空、加强并全面落实大学生安全教育工作,为高校创新大学生安全教育工作提供借鉴经验和新的思考。     

Some augmented approaches to the improved stability criteria for linear systems with time-varying delays

This work investigates the improved stability conditions for linear systems with time-varying delays via various augmented approaches. Some augmented approaches are augmented Lyapunov-Krasovskii functionals, augmented zero equalities, and the augmented zero equality approach. At first, by constructing augmented Lyapunov-Krasovskii functionals including the state vectors which were not considered in the previous works and augmented zero equalities, a stability criterion is proposed in the forms of linear matrix inequalities. Through the proposed Lyapunov-Krasovskii functionals and an additional functional derived from the integral inequality, a slightly improved result is derived. The proposed results do not consider the increase in the computational complexity to achieve a larger delay bound. So, by applying the augmented zero equality approach, which is a method of grafting the proposed augmented zero equality proposed in Finsler Lemma, to the proposed result, an enhanced stability result was derived. Also, the computational complexity is reduced by appropriately adjusting any vector of the integral inequality utilized in the proposed criteria. By applying some numerical examples to the proposed conditions, the effectiveness and superiority of the results are confirmed.     

New approaches to positive observer design for discrete-time positive linear systems

This paper aims at providing new design approaches for positive observers of discrete-time positive linear systems based on a construction method of linear copositive Lyapunov function for positive systems. First, an efficient positive observer design approach is proposed by using linear programming such that the observer error system is exponentially stable. Furthermore, an interval observer design is proposed for uncertain positive systems. Then, the results are extended to positive time delay systems. In contrast with the previous design approaches, the new design method provides a general observer design with lower computational burden. Finally, three comparison examples are given to show the merit of the new design approach.     

高等学校科研机构的分类方法研究

高等学校科研机构在科教兴国的战略中发挥着重要的作用，扮演着骨干角色。数据挖掘是一个完整的数据存储、数据仓库和决策支持的统一体，广泛应用于零售、制造、通信、卫生保健、保险和运输等行业。本文利用数据挖掘中的聚类分析技术，提出了一种两步聚类算法。利用该算法可以将高校科研机构根据其历史数据和信息进行分类，科研机构的管理者根据分类的结果能够识别科研机构之间的异同．从而实现科研机构的分类管理，同时也能够给科研资源的合理分配提供指导。     

Improved approaches to stability criteria for neural networks with time-varying delays

In this paper, the problem of stability analysis for neural networks with time-varying delays is considered. By the use of a newly augmented Lyapunov functional and some novel techniques, sufficient conditions to guarantee the asymptotic stability of the concerned networks are established in terms of linear matrix inequalities (LMIs). Three numerical examples are given to show the improved stability region of the proposed works.     

A lens of many facets. Science through a family's eyes

This essay argues for the relevance of the history of family life to the history of science, taking the example of the Exners of Vienna. The Exners were an influential case of the nineteenth-century European phenomenon of the "scientific dynasty". The focus here is on their collaborative research on color theory at the turn of the twentieth century. At first glance, this project looks like a reactionary strike against aesthetic innovation, a symptom of what historians assume was an unbridgeable gulf between scientific reason and artistic modernism. We can better understand the Exners' motivations by situating this research at the intersection of the family's public and private lives. The domestic context sheds light on their use of such scientific terms as "subjective", "normal", and "universal", providing a more nuanced sense of what rationality really meant in fin-de-siècle Vienna.     

上海世博会融资方式研究

回顾历届世博会举办准备时期的融资方式,指出有效合理的融资方式对于成功举办世博会具有重要意义;并在借鉴各届世博会和奥运会经验的基础上,分析2010年上海世博会的融资方式,并提出相关建议。     

Indexing and stemming approaches for the Czech language

This paper describes and evaluates various stemming and indexing strategies for the Czech language. Based on Czech test-collection, we have designed and evaluated two stemming approaches, a light and a more aggressive one. We have compared them with a no stemming scheme as well as a language-independent approach (n-gram). To evaluate the suggested solutions we used various IR models, including Okapi, Divergence from Randomness (DFR), a statistical language model (LM) as well as the classical tf idf vector-space approach. We found that the Divergence from Randomness paradigm tend to propose better retrieval effectiveness than the Okapi, LM or tf idf models, the performance differences were however statistically significant only with the last two IR approaches. Ignoring the stemming reduces generally the MAP by more than 40%, and these differences are always significant. Finally, if our more aggressive stemmer tends to show the best performance, the differences in performance with a light stemmer are not statistically significant.     

论技术跨越的实现途径以及对我国政府的启示

技术跨越的本质就是一种非连续性的技术进步方式,旨在迅速提高技术水平,缩短与技术领先者的差距。技术跨越的实现主要有三种途径:自主、引进、合作。理论和实践经验证明,政府的干预是实现技术跨越的重要条件,但是在不同创新阶段,政府工作的重点有所不同。     

Modelling information flow for organisations: A review of approaches and future challenges

Modelling is a classic approach to understanding complex problems that can be achieved diagrammatically to visualise concepts, and mathematically to analyse attributes of concepts. An organisation as a communicating entity is a made up of constructs in which people can have access to information and speak to each other. Modelling information flow for organisations is a challenging task that enables analysts and managers to better understand how to: organise and coordinate processes, eliminate redundant information flows and processes, minimise the duplication of information and manage the sharing of intra- and inter-organisational information.     

Understanding the dynamics of users’ belief in software application adoption

Research has identified numerous factors that influence initial technology adoption decisions. However, extant studies consider beliefs to be static rather than dynamic over the adoption time-span. Various models have been employed to identify adoption behavior, pre- and post-adoption, however, there is little research on the dynamics of users’ belief structures over time and the inter-relationships among them. This study aims to investigate the dynamic nature of users’ beliefs and the relationships among their dynamics, i.e., rates of change. We test our research model based on data obtained at three time-windows using a parallel-growth process model. The results reveal that self-efficacy, usefulness and intention to use are likely to be dynamic, and increase with time. The rate of change in self-efficacy influences the rate of change in usefulness, which in turn affects the rate of change in intention to use. This study theoretically contributes to expanding the extant cross-sectional TAM research to include time-phased TAM studies, and highlights the role of self-efficacy as an important determinant of the dynamics.     

三种数值方法在几种六道木分类中的应用

   In the last 10—20 years there has bee n increasing awareness of the problem con- cerning the aims and practices of taxonomy.  In particular, there has been growing interest in the development of numerical methods in biological taxonomy as an aid to making systematics a quantitative science, a step which comes in time to almost every scientific discipline.       Numerical taxonomy is the evaluation by numerical methods of the affinity or  similarity between taxonomic units and the employment of these affinities in erecting a hierarchic order of taxa.  The present rapid development of these ideas is presuma- bly a result of the development of computer techniques.       Numerical taxonomic approach has been applied to the studies of entomology and microbiology in China to some extent since 1975. But so far it hasn’t been commonly used in botany.  The present report is a preliminary study on 9 spp. of the genus Abelia.  A set of binary data with 54 characters  is  used  for  computing association coefficient; and a set of quantitative data with 47 characters for distance coefficient and correlation coefficient. For the mathematical models were chosen the non-metric  simple matching association coefficient, the geometrical distance of Riemannian space and correlation coefficient.  Computational procedures are stepwise presented in detail and computer programmes are written in the background of Algol-60 language. Cluster analysis is compared with simple linkage,  average  linkage  and multi-correlation.      The results of DC and CC for 9 spp. of Abelia agree closely with the traditional taxonomy, because the data we collected mainly come from morphological characters. It would seem that the results of quantita tive data are more appropriate for  seed plants.  It is, therefore, postulated that our programes are complementary and very useful to a wide range of classification entities, such as microbes, animals and plants in present situation in China.      In conclusion, a comparison between the  conventional taxonomy  and  numerical taxonomy has been made, and a brief discussion of three problems, i.e. the monothetic versus polythetic, divisive versus agglomerative, weighting versus unweighting.