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961.
962.
国内外农业信息化研究述评 总被引:8,自引:0,他引:8
国外农业信息化建设依靠大力推广应用信息技术,建立了完善的农业信息服务系统、健全的农业信息化政策法规,这些是我国农业信息化建设中值得借鉴的经验。本文在综合国内外农业信息服务体系和信息技术应用等方面的理论和实践研究的基础上,提出了有待进一步研究和建设的内容,旨在为发展我国西部农业信息化提供一定的借鉴和启示。 相似文献
963.
Result merging methods in distributed information retrieval with overlapping databases 总被引:5,自引:0,他引:5
In distributed information retrieval systems, document overlaps occur frequently among different component databases. This
paper presents an experimental investigation and evaluation of a group of result merging methods including the shadow document
method and the multi-evidence method in the environment of overlapping databases. We assume, with the exception of resultant
document lists (either with rankings or scores), no extra information about retrieval servers and text databases is available,
which is the usual case for many applications on the Internet and the Web.
The experimental results show that the shadow document method and the multi-evidence method are the two best methods when
overlap is high, while Round-robin is the best for low overlap. The experiments also show that [0,1] linear normalization
is a better option than linear regression normalization for result merging in a heterogeneous environment.
相似文献
Sally McCleanEmail: |
964.
Previous papers on grey literature by the authors have described (1) the need for formal metadata to allow machine understanding
and therefore scalable operations; (2) the enhancement of repositories of grey (and other) e-publications by linking with
CRIS (Current Research Information Systems); (3) the use of the research process to collect metadata incrementally reducing
the threshold barrier for end-users and improving quality in an ambient GRIDs environment. This paper takes the development
one step further and proposes “intelligent” grey objects. The hypothesis is in 2 parts: (1) that the use of passive catalogs
of metadata does not scale (a) in a highly distributed environment with millions of nodes and (b) with vastly increased volumes
of R&D output grey publications with associated metadata; (2) that a new paradigm is required that (a) integrates grey with
white literature and other R&D outputs such as software, data, products and patents (b) in a self-managing, self-optimizing
way and that this paradigm manages automatically curation, provenance digital rights, trust, security and privacy. Concerning
(1) existing repositories provide catalogs; harvesting takes increasing time ensuring non-currency. The end-user expends much
manual effort/intelligence to utilize the results. The elapsed time of (1) the network (2) the centralized (or centrally controlled
distributed) catalog server searches (3) end-user intervention becomes unacceptable. Concerning (2) there is no paradigm currently
known to the authors that satisfies the requirement. Our proposal is outlined below. Hyperactive combines both hyperlinking
and active properties of a (grey) object. Hyperlinking implies multimedia components linked to form the object and also external
links to other resources. The term active implies that objects do not lie passively in a repository to be retrieved by end-users.
They “get a life” and the object moves through the network knowing where it is going. A hyperactive grey object is wrapped
by its (incrementally recorded) formal metadata and an associated (software) agent. It moves through process steps such as
initial concept, authoring, reviewing and depositing in a repository. The workflow is based on the rules and information in
the corporate data repository with which the agent interacts. Once the object is deposited, the agent associated with it actively
pushes the object to the end-users (or systems) whose metadata indicate interest or an obligation in a workflowed process.
The agents check the object and user (or system) metadata for rights, privacy, security parameters, and for any charges and
assure compatibility. Alternatively the object can be found passively by end-user or system agents. The object can also associate
itself with other objects forming relationships utilising metadata or content. Declared relationships include references and
citations; workflowed relationships include versions and also links to corporate information and research datasets and software;
inferenced relationships are discovered relationships such as between documents by different authors developed from an earlier
idea of a third author. Components of this paradigm have been implemented to some extent. The challenge is implementing—respecting
part two of the hypothesis—the integration architecture. This surely is harnessing the power of grey.
相似文献
Anne AssersonEmail: |
965.
绿色营销实施初探 总被引:2,自引:0,他引:2
刘勇 《辽宁科技学院学报》2007,9(2):56-57
传统营销的研究焦点是由企业、顾客与竞争者构成的所谓的"魔术三角".绿色营销研究的焦点是对其进一步扩展.它是通过环境保护的手段来满足人类的长远需要,因此,假以时日,有关方面最终会求同存异,协调行动,实现全球社会经济的可持续发展. 相似文献
966.
SA8000认证制度,是经济全球化的本性和发展需要,是企业通向国际市场的通行证.目前,我国企业在实施SA8000认证制度的过程中还存在许多问题和困难,企业要更新观念,采取积极的应对措施,参与SA8000认证,努力提高我国企业在国际市场上的竞争力. 相似文献
967.
以市场需求为导向构建高职"商务英语专业"特色课程体系 总被引:1,自引:0,他引:1
构建高职“商务英语专业”特色课程体系,需要贯彻“产学研结合”的育人模式,优化课程内容和授课方式,完善实践性环节,落实“两双”制度,加强课程建设,从而形成专业特色优势。 相似文献
968.
笔者结合工作实际,阐述了在工作实践中对技术资料整理过程中所遇见的一些情况,包含了从准备工作到开展工作.直至工作结束所获得的一些经验及心得. 相似文献
969.
Tumblin A 《The Journal of perinatal education》2007,16(4):68-69
A childbirth educator reveals her dilemma in teaching evidence-based practice in today's high-tech birth climate. She focuses on strategies to use when sharing epidural information with expectant parents. 相似文献
970.
王丽 《北京工业职业技术学院学报》2007,6(2):130-132,129
在目前国内外建设多层次资本市场的大背景下,分析了我国多层次资本市场和成熟的多层次资本市场的差距,明确了我国构建三板市场的积极意义,提出了产权交易市场是我国三板市场的基础,研究了产权交易市场的功效和以产权交易市场为基础构建我国三板市场的路径. 相似文献