Collaborative bibliography

A bibliography is traditionally characterized by the judgments, bounded by explicit selection criteria, made by a single compiler. Because these criteria concern the attributes ascribed to a work and the needs of readers, bibliographic work is largely conceptual even across technological eras and domains. Yet, the development of networked information services, made possible by WWW infrastructure, has enabled very large numbers of people to discover, organize, and publish information, including bibliographies. Indeed, bibliographies, or at least bibliography-like artifacts, are a common genre of website, often published by people without specialized skills in information organization who follow non-rigorous selection procedures. Nevertheless, even if the items from these lists are poorly selected and described, this publishing activity is fundamentally important because it structures information locally, creating a patchy network of secondary access points. In turn, these access points enable information discovery, the formation and development of communities of interest, the estimation of document relevance by search engines, and so on. In sum, this activity, and the enabling technical infrastructure, invites bibliographies to take on new interactive possibilities. The aim of this article is to extend the traditional view of bibliography to encompass collaborative possibilities for wide, or narrow, participation in the shaping of bibliographies and the selection of items. This is done by examining the nature of bibliography on the Web, by proposing a conceptual model that opens bibliography to participatory practices, and by discussing a case study where a team sought to develop a bibliography of electronic resources. This examination reveals splendid opportunities for expanding the notion of bibliography with participatory policies while remaining true to its ancient roots.     

On nonlinear discrete-time systems driven by Markov chains

The behavior of a class of hybrid systems in discrete-time can be represented by nonlinear difference equations with a Markov input. The analysis of such a system usually starts by establishing the Markov property of the joint process formed by combining the system's state and input. There are, however, no complete proofs of this property. This paper aims to address this problem by presenting a complete and explicit proof that uses only fundamental measure-theoretical concepts.     

中国投资引致碳排放与经济增长的空间特征及脱钩测度

长期以来中国经济增长依赖投资,在低碳经济时代下,投资引致的碳排放和经济增长脱钩关系应受到关注。以往对此研究相对较少,且忽略了投资通过不同区域间产业联系所引发的间接脱钩。本文引入面积元并结合投入产出表以改进脱钩模型,研究了2007-2010年间全社会固定资产投资直接、间接引致的中国30个省区市碳排放和经济增长的空间特征及脱钩关系。结果显示：①大部分省份由投资引致的经济增长比碳排放略快,两者为弱脱钩关系;北京和上海实现强脱钩发展,内蒙古、宁夏等资源型省份多为扩张负脱钩;②投资直接引致农林牧渔业实现脱钩发展,建筑业和服务业的直接脱钩状态相对较差;工业投资引致不同区域各产业的间接负脱钩状态最多,服务业受其他行业投资间接影响多呈现负脱钩状态。低碳发展相关政策的制定应考虑地区间的经济联系和产业间的拉动作用,适当补偿承担高碳生产环节的地区,避免盲目发展可能转移大量碳排放的产业。     

Towards a unified approach to document similarity search using manifold-ranking of blocks

Document similarity search (i.e. query by example) aims to retrieve a ranked list of documents similar to a query document in a text corpus or on the Web. Most existing approaches to similarity search first compute the pairwise similarity score between each document and the query using a retrieval function or similarity measure (e.g. Cosine), and then rank the documents by the similarity scores. In this paper, we propose a novel retrieval approach based on manifold-ranking of document blocks (i.e. a block of coherent text about a subtopic) to re-rank a small set of documents initially retrieved by some existing retrieval function. The proposed approach can make full use of the intrinsic global manifold structure of the document blocks by propagating the ranking scores between the blocks on a weighted graph. First, the TextTiling algorithm and the VIPS algorithm are respectively employed to segment text documents and web pages into blocks. Then, each block is assigned with a ranking score by the manifold-ranking algorithm. Lastly, a document gets its final ranking score by fusing the scores of its blocks. Experimental results on the TDT data and the ODP data demonstrate that the proposed approach can significantly improve the retrieval performances over baseline approaches. Document block is validated to be a better unit than the whole document in the manifold-ranking process.     

LABRADOR: Efficiently publishing relational databases on the web by using keyword-based query interfaces

A vast amount of valuable information, produced and consumed by people and institutions, is currently stored in relational databases. For many purposes, there is an ever increasing demand for having these databases published on the Web, so that users can query the data available in them. An important requirement for this to happen is that query interfaces must be as simple and intuitive as possible. In this paper we present LABRADOR, a system for efficiently publishing relational databases on the Web by using a simple text box query interface. The system operates by taking an unstructured keyword-based query posed by a user and automatically deriving an equivalent SQL query that fits the user’s information needs, as expressed by the original query. The SQL query is then sent to a DBMS and its results are processed by LABRADOR to create a relevance-based ranking of the answers. Experiments we present show that LABRADOR can automatically find the most suitable SQL query in more than 75% of the cases, and that the overhead introduced by the system in the overall query processing time is almost insignificant. Furthermore, the system operates in a non-intrusive way, since it requires no modifications to the target database schema.     

AVS实现重大系统集成创新

数字音视频产业是我国信息产业的三大组成部分之一,我国牵头开发制定的数字音视频编解码技术标准(AVS)是本领域的基础性标准。本文主要介绍AVS的开发背景、研制过程、主要创新点以及产业化前景。AVS以标准和专利为纽带,打通了技术到产业转移的大循环,探索出了一条实现重大系统集成创新的道路。AVS标准不仅是我国构建完整的数字音视频产业链的技术源头,也是全球范围内数字音视频产业发展的重要选择。     

Assessing user-specific difficulty of documents

On the web, a huge variety of text collections contain knowledge in different expertise domains, such as technology or medicine. The texts are written for different uses and thus for people having different levels of expertise on the domain. Texts intended for professionals may not be understandable at all by a lay person, and texts for lay people may not contain all the detailed information needed by a professional. Many information retrieval applications, such as search engines, would offer better user experience if they were able to select the text sources that best fit the expertise level of the user. In this article, we propose a novel approach for assessing the difficulty level of a document: our method assesses difficulty for each user separately. The method enables, for instance, offering information in a personalised manner based on the user’s knowledge of different domains. The method is based on the comparison of terms appearing in a document and terms known by the user. We present two ways to collect information about the terminology the user knows: by directly asking the users the difficulty of terms or, as a novel automatic approach, indirectly by analysing texts written by the users. We examine the applicability of the methodology with text documents in the medical domain. The results show that the method is able to distinguish between documents written for lay people and documents written for experts.     

软技术对操作者学习效率影响的实证研究

软技术作为一种限制不同操作者之间,以及操作者与工具之间进行协作的规则体系,改变了操作者决策依据和动作的发生方式,最终影响了操作者的学习效率;本文证实了软技术对操作者学习效率的影响:在同样任务条件下,在软技术的规范下,操作效率的改进时间,要短于自学习的方式;也就是在软技术作用下,操作效率将先达到比较稳定的高点,得到了证实;操作者效率改进过程发生了变化,操作效率改进曲线有突变,软技术明显地改变了效率改进曲线;而无软技术作用时,操作者效率改进是平缓的,无突变的。     

Academic spin-off’s transfer speed—Analyzing the time from leaving university to venture

For academic spin-offs I analyze the length of the time period between the founder’s leaving of academia and the establishment of her firm. A duration analysis reveals that a longer time-lag is caused by the necessity of assembling complementary skills, either by acquisition by a single founder or by searching for suitable team members. Furthermore, new ventures are established faster if there has been high-level technology transfer, if the founders have access to university infrastructure, or if they receive informal support by former colleagues.     

辅助图与标号三元图的等价性

20世纪 70年代 ,刘彦佩通过构造图的辅助图 ,得到判定图是否平面的充分必要条件 .图的标号三元图刻画了图的内在结构 ,也可以刻画图是否平面 .证明了图的辅助图是否平衡以及标号三元图是否平衡是等价的 ;并进一步指出 ,用辅助图来判定要优于用标号三元图 .     

The integration of old and new technological paradigms in low- and medium-tech sectors: The case of mechatronics

This article addresses the internal transformation of low- and medium-tech (LMT) sectors from a technological perspective, analysing the absorption of radical new technologies by low- and medium-technology (LMT) firms and their integration into frameworks dominated by older technologies. Through an empirical analysis of a cluster of mechatronic companies, the paper highlights some of the main features of the integration process and provides a preliminary assessment of whether the phenomenon is more likely to occur within or between companies, that is through the absorption of new technologies by each firm individually or by means of linkages between specialised mono-technology companies.     

矩阵的一类特殊乘积及其广义行列式性质

本文受文献[1]的启发,定义了方阵和矩阵之间的一类特殊的乘积,即方阵左乘到矩阵中的若干行或右乘到矩阵中的若干列。利用[1]中的定理1,证明了这种乘积的广义行列式所满足的一个等式。利用这个等式,给出Liouville公式的一个推广。     

河北省耕地占用与GDP增长的脱钩分析

在经济发展过程中,大量优质耕地被占用已成为严重制约我国可持续发展的重大挑战.本文基于脱钩理论,运用经济合作与发展组织(OECD)提出的脱钩指数计算模型和Tapio等划分的脱钩状态,构建脱钩模型,计算脱钩弹性,建立脱钩程度坐标图,并以河北省为例分析各阶段脱钩状态及其原因,以期指导经济发展过程中的耕地保护问题.研究表明:1990年～1999年脱钩弹性值变化平缓,由强脱钩向复钩状态变化,建设占用耕地压力增大;2000年～2005年脱钩弹性值变化剧烈,由强脱钩向复钩状态变化,建设占用耕地压力较前一阶段急剧减小后增大;2006年～2007年脱钩弹性减小,呈现弱脱钩状态,建设占用耕地压力减小.总体来看,建设占用耕地与非农GDP产值的关系曲线呈现"M"型变化,耕地保护政策、措施实施效果明显.随着经济发展,在未来一段时期建设占有耕地与非农GDP产值关系有向复钩状态发展的趋势,建设占用耕地压力将增大,为此应加大建设占用耕地管理力度,采用节约集约利用土地的政策和措施.     

Motivation of software developers in Open Source projects: an Internet-based survey of contributors to the Linux kernel

The motives of 141 contributors to a large Open Source Software (OSS) project (the Linux kernel) was explored with an Internet-based questionnaire study. Measured factors were both derived from discussions within the Linux community as well as from models from social sciences. Participants’ engagement was particularly determined by their identification as a Linux developer, by pragmatic motives to improve own software, and by their tolerance of time investments. Moreover, some of the software development was accomplished by teams. Activities in these teams were particularly determined by participants’ evaluation of the team goals as well as by their perceived indispensability and self-efficacy.     

Droplet-based microfluidic washing module for magnetic particle-based assays

In this paper, we propose a continuous flow droplet-based microfluidic platform for magnetic particle-based assays by employing in-droplet washing. The droplet-based washing was implemented by traversing functionalized magnetic particles across a laterally merged droplet from one side (containing sample and reagent) to the other (containing buffer) by an external magnetic field. Consequently, the magnetic particles were extracted to a parallel-synchronized train of washing buffer droplets, and unbound reagents were left in an original train of sample droplets. To realize the droplet-based washing function, the following four procedures were sequentially carried in a droplet-based microfluidic device: parallel synchronization of two trains of droplets by using a ladder-like channel network; lateral electrocoalescence by an electric field; magnetic particle manipulation by a magnetic field; and asymmetrical splitting of merged droplets. For the stable droplet synchronization and electrocoalescence, we optimized droplet generation conditions by varying the flow rate ratio (or droplet size). Image analysis was carried out to determine the fluorescent intensity of reagents before and after the washing step. As a result, the unbound reagents in sample droplets were significantly removed by more than a factor of 25 in the single washing step, while the magnetic particles were successfully extracted into washing buffer droplets. As a proof-of-principle, we demonstrate a magnetic particle-based immunoassay with streptavidin-coated magnetic particles and fluorescently labelled biotin in the proposed continuous flow droplet-based microfluidic platform.     

国际反垄断政策协调的可行途径比较分析

建立国际反垄断政策协调体制的尝试主要是由欧盟和美国推动的,欧盟希望整合国际反垄断法律并在WTO范围内执行,而美国则希望组成一个国际竞争网络(ICN)作为多边合作平台。通过比较,可以发现WTO和ICN途径之间同时又是互补的,这将导致两个体制的长期共存。     

《傲慢与偏见》与《金粉世家》——爱情观以及影响婚姻的因素

《傲慢与偏见》是英国著名女作家简.奥斯汀的一部力作,描述的是青年男女恋爱与婚姻。本文作者试通过分析小说四起典型的婚姻来讨论性格是如何影响一个人的婚姻价值定位的,以及简.奥斯汀对待婚姻的看法;《金粉世家》中的男女主人公也是存在类似的命运,真挚的爱情受到世俗偏见的考验,爱情的力量是伟大的,二人很幸福地结合了,然而最终作者却是以悲剧结局了整部作品。两部作品的爱情与婚姻相同而又具有差异性。     

The Victorian Information Society: Surveillance, Bureaucracy, and Public Librarianship in 19th-Century Britain

Contrary to the "retro" image often awarded them, and despite their continuing enthusiasm and responsibility for the organization of printed materials, librarians are upbeat about the prospects of an information society driven primarily by electronic technologies, but in which libraries can play an important part. Public librarians detect a natural correlation between the historic democratic mission of their institution and the increased accessibility made possible by digitalized sources. The library community's acceptance of the information society idea as a "given" social phenomenon supports discourses that play down historical continuities and herald the dawn of a new age. Such discourses ignore or reject historical evidence that points to the existence of past information societies, revolutions, and infrastructures defined, in part, by the operation of indirect surveillance, constituted by the bureaucratic information systems of modernity. Victorian Britain serves as a good example of an early information society, to which public libraries, themselves micro-information societies, contributed significantly. The role played by public librarians in the Victorian information society, illustrated in this article by evidence drawn from the contemporary library press, is seen in their preoccupation with the surveillance and ordering of knowledge; their adoption for library operations of the businesslike, bureaucratic procedures described recently by business historians; and their panoptic tracking of users and their activities.     

习惯性或忠诚性购买行为下的新产品扩散

消费者习惯性或忠诚性购买行为对新产品扩散有阻滞作用，从而影响Bass模型在非垄断情况下的应用。在一定条件下通过构建反映这种行为的顾客期望状态转移矩阵，利用惯性系数对Bass宏观创新采用概率做出修正，得出了惯性购买行为下的新产品扩散模型。