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11.
John W. Hoopes 《Archives and Museum Informatics》1997,11(2):87-105
In the final scene of Raiders of the Lost Ark, a crate containing the object of Indiana Jones' quest is wheeled into an immense warehouse for indefinite storage and questionable research access. Unfortunately, this fate is not all that far from reality. Collections of archaeological and ethnographic materials ranging from stone axes, broken potsherds, and carved monuments to baskets, ceremonial masks, and skin canoes have been held by museums collections since the Renaissance. However, their inestimable value and unique conservation and curatorial requirements often conspire to remove them from the reach of all but the most diligent scholars. The potential of the Web to enhance the quality of research on archaeological and ethnographic collections is enormous. This paper will examine ways that one can use the Web to enhance research and improve access to a variety of materials; while there are many other resources for archaeology available on the Web, this paper focusses on museum-related sites. It will also explore the potential of the Web for innovative research strategies. Digitization of catalogs, associated documents, and images to help one locate and study collections and specific artifacts are just one approach. Others include the connection of devices to the Web, such as cameras and microscopes, the creation of virtual reference collections, and the establishment of research networks that will enhance the identification and analysis of material culture. This paper will also consider the role the Web could play in issues of cultural property, contributing to and in many ways intensifying ongoing debates of ownership, curation, conservation, and repatriation of sensitive materials. 相似文献
12.
基于概率神经网络的文本自动分类研究 总被引:10,自引:2,他引:10
本文提出了将一种径向基网络的重要变形———概率神经网络应用于文本自动分类的研究 ,与常用的K 最邻近法相比 ,具有一定的优势 ,特别是在训练集中各类的训练样本数很不平衡时 ;与BP等其他神经网络相比 ,其特点是需调节的参数少 ,不需确定隐层数、隐层中的神经元数量等网络结构 ,比较容易使用。此外 ,从研究中的不同特征选择的评价函数来看 ,它们对分类有一定的影响 ,应用X2 统计进行特征选择的分类正确率最高 ,其次是文本证据权 ,而期望交叉熵的效果最差 ,说明特征选择在文本自动分类中也是非常重要的。 相似文献
13.
网络环境下数字图书馆的安全与防范措施 总被引:14,自引:0,他引:14
阐述了网络环境下影响数字图书馆安全的因素,提出了保护数字图书馆信息安全的防范措施。 相似文献
14.
基于B/S模式的科技文献管理系统的策略和初步实现* 总被引:1,自引:0,他引:1
通过对国内外文献管理工具的现状与发展趋势进行分析, 并结合当前文献信息的网络化特征, 进行了文献管理系统基于B/S (浏览器/服务器) 模式下的策略研究, 并讨论了相关的实现技术。本文设计了一个基于B/S 模式的文献管理系统框架, 通过对用户的权限控制, 以及对不同类型的科技文献信息的管理、批量导入和导出, 使用户可以通过Internet 对文献信息进行有效的检索、维护、使用和共享, 并进行了初步的系统(Ref Manager) 开发和实现。 相似文献
15.
This article reviews the Invisible Farmer project – the largest study of Australian women on the land – a third of the way through its three year funding period. It introduces the aims of this collaborative and multidisciplinary project, focusing on the role of records and oral histories in the creation of new narratives, and the task of raising public awareness of the important historical and contemporary contributions made by Australian women farmers. We examine the way digital platforms work to curate records and promote research, and outline the important role that the Australian Women’s Register, a core project of the Australian Women’s Archives Project, will play in achieving outcomes. 相似文献
16.
Relational transgressions are emotionally difficult for those who directly experience the transgression. Less is known about how transgressions affect those located within the personal network of a relational transgression victim. This study explored how network members engaged in support marshaling in response to another’s transgression experience. Results indicate that some participants marshaled support, citing four reasons for their actions: perceived insufficiency, camaraderie, personal ramifications, and personal values. We explore these reasons for marshaling support and discuss them within the broader context of support marshaling and relational transgressions. 相似文献
17.
[目的/意义]为增强弱信号的内涵研究,对其全生命周期过程下的各阶段要素以及要素间的联系进行探寻,以期获得一定程度上的理论贡献,同时也为相关组织在开展弱信号管理实践时提供理论指导。[方法/过程]在对弱信号概念研究现状进行梳理的基础上,结合意义构建理论给出了弱信号概念界定。随后,通过与信息生命周期、新兴议题生命周期进行类比,提出弱信号生命周期理念。进而采用系统动态学方法开展系统思考,使用因果回路图进行系统建模,运用存量流量图进行仿真模拟。[结果/结论]弱信号生命周期包含4个阶段:侦测、关联、传递、抉择,相应的系统动态学模型所具备的现实性得到验证,且通过情景模拟确认了4个关键辅助变量:外界噪声干扰程度、弱信号分析效率、组织内相互信任程度、决策者信任程度。在整体研究的基础上,给出弱信号管理过程中可能会遇到的障碍以及应对策略。 相似文献
18.
This study tests how the density of the social network in which intergroup contact takes place might affect the extent to which contact improves intergroup attitudes. Having contact with more outgroup members in dense social networks, in which everybody knows each other, may reinforce contact's positive effect. In this case, outgroup contact is shared with ingroup members, which suggests positive ingroup norms toward the outgroup. Alternatively, more contact in denser networks may improve intergroup attitudes less because density may increase subtyping or reduce the salience of ethnic group memberships. These competing hypotheses are tested among white American adults in a nonprobability online sample (N = 305) and in a representative national sample (N = 1270). In both studies, contact is associated with more positive attitudes toward racial outgroups but the positive contact effect is weakened if that contact takes place in a denser social network. 相似文献
19.
Ke He Yong-Ping Xin Ying Shan Xian Zhang Hou-Hui Song Wei-Huan Fang 《Journal of Zhejiang University. Science. B》2019,(8):660-669
目的:探明单增李斯特菌RsbR的两个保守磷酸化位点是否影响SigB(sigmaB)的表达.创新点:解析了RsbR在单增李斯特菌中SigB网络调控中的作用.方法:通过基因缺失、定点突变和回补技术构建rsbR基因缺失株、回补株和回补突变菌株,进行酸应激条件下的生长能力和强酸条件下的存活能力试验,并检测在酸应激下菌株中的SigB基因和蛋白表达的改变情况.结论:RsbR缺失能够显著降低单增李斯特菌的抗酸应激能力和下调SigB表达,RsbR-175位点是SigB调控途径中RsbT释放的先决条件. 相似文献
20.
Jessica L. Ford Jacob S. Ford Seth S. Frei Andrew Pilny Brenda L. Berkelaar 《Journal of Applied Communication Research》2016,44(3):316-335
Persistent school shootings have generated ongoing pressure to assess and enhance crisis communication effectiveness via strategies such as resilience-building and post-crisis restoration. A network perspective offers a robust, multilevel approach for examining complex information flows among community, campus, and individual actors affected by crises. Drawing on relational and structural embeddedness and Uncertainty Management Theory, we offer nine propositions that help explain structural and relational changes in a network over time. Although theoretically driven, these propositions are primarily functional, offering practical implications for safety officials and administrators trying to understand, prepare for, and respond to crises. Thus, we suggest measures and recommendations to improve information flow, uncertainty management, and resilience before, during, and after a crisis. 相似文献