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1.
伴随多元化时代的来临,用户的知识需求日益多元化、专业化,对图书馆服务提出了新的挑战。对智慧图书馆微观知识生态系统运行机理的研究,能够为新型知识服务提供理论基础,保障知识资源进行有效的优化整合,实现服务升级。文章在简要分析智慧图书馆微观知识生态系统四大要素的基础上,着重从社会发展、技术进步,知识富集、优化调整和需求驱动、服务升级三方面探讨其形成动因,重点分析智慧图书馆微观知识生态系统的生命周期,最后从合作、循环和保障三方面探讨其运行机理。 相似文献
2.
论电子阅览室的知识导航与信息服务 总被引:3,自引:0,他引:3
尤如春 《农业图书情报学刊》2004,16(11):83-85
本文立足于知识导航与信息服务,对网络环境下电子阅览室的服务内容、服务保障、目前面临的现状进行了论述,并提出了服务对策。 相似文献
3.
近年来,我省先后从国内外引进了20多个鸡种,10多个牛种、羊种和猪种等,因其高效而占领了我省市场。同时存在着盲目引种,品种多乱、杂等问题。伴随着少数高产畜禽品种的普及推广,使各地固有的许多品种资源迅速减少或消失。因此,针对陕西畜禽品种资源的现状问题,并结合近年来畜牧业生产中的实际状况,特就如何搞好地方畜禽品种资源的保护及开发利用提出建议与对策。 相似文献
4.
RAPD技术对地方鸡种群体遗传结构的分析 总被引:16,自引:1,他引:15
利用RAPD技术对4个地方鸡种和1个引进鸡种的群体遗传结构进行分析,通过筛选的5个随机引物OPH-02、OPH-05、OPH-13、OPH-16、OPG-07对5个鸡种的池DNA进行多态性研究,结果表明:5个引物共产生条带61个,扩增产物片段的长度一般从150bp-4kb。 相似文献
5.
Pest Management in Traditional Tropical Agroecosystems: Lessons for Pest Prevention Research and Extension 总被引:1,自引:0,他引:1
Helda Morales 《Integrated Pest Management Reviews》2002,7(3):145-163
Based on current agroecological theory and IPM practices, this review explores the role of traditional practices, involving
site selection, soil management, timing of planting and harvesting, crop resistance, intercropping, weed management, harvest
residue management, post-harvest management, natural enemies management, mechanical control, repellents and traps in the natural
regulation of potential pests. In synthesis, the literature suggests that although pest management professionals focus their
efforts on pest control, the preventative approach taken by traditional farmers is more effective. Potential constraints to
the implementation of this preventive pest management approach include:(1) lack of integration of ecological theory and pest
management, (2) lack of cooperation among social and biological scientists, and (3) lack of real efforts to work with farmers
as equals and support mechanisms that protect their knowledge.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
6.
Denis J. Sonwa Ousmane Coulibaly A. Akinwumi Adesina Stephan F. Weise Mathurin Tchatat 《Integrated Pest Management Reviews》2002,7(3):191-199
Imports of pesticides have long been subsidised for use in the cocoa agroforests of the humid forest zone of southern Cameroon.
With the liberalisation of the cocoa and pesticides sectors and the devaluation of the local currency (CFA franc), farmers
are facing fluctuations in the price paid for cocoa and the high cost of farm inputs. Without the support of the extension
services, they themselves have developed traditional integrated control methods based on the use of plant extracts mixed with
conventional pesticides. From a survey of 300 cocoa farmers, the study assesses the farmers' command of these methods, the
pests controlled, the problems encountered and the institutional constraints in the definition and dissemination of integrated
control methods. The study concludes with recommendations for research and development towards the better definition and dissemination
of integrated control methods.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
7.
Johnson Chris J. Boyce Mark S. Mulders Robert Gunn Anne Gau Rob J. Cluff H. Dean Case Ray L. 《Landscape Ecology》2004,19(8):869-882
Multiscale analyses are widely employed for wildlife-habitat studies. In most cases, however, each scale is considered discrete and little emphasis is placed on incorporating or measuring the responses of wildlife to resources across multiple scales. We modeled the responses of three Arctic wildlife species to vegetative resources distributed at two spatial scales: patches and collections of patches aggregated across a regional area. We defined a patch as a single or homogeneous collection of pixels representing 1 of 10 unique vegetation types. We employed a spatial pattern technique, three-term local quadrat variance, to quantify the distribution of patches at a larger regional scale. We used the distance at which the variance for each of 10 vegetation types peaked to define a moving window for calculating the density of patches. When measures of vegetation patch and density were applied to resource selection functions, the most parsimonious models for wolves and grizzly bears included covariates recorded at both scales. Seasonal resource selection by caribou was best described using a model consisting of only regional scale covariates. Our results suggest that for some species and environments simple patch-scale models may not capture the full range of spatial variation in resources to which wildlife may respond. For mobile animals that range across heterogeneous areas we recommend selection models that integrate resources occurring at a number of spatial scales. Patch density is a simple technique for representing such higher-order spatial patterns. 相似文献
8.
对柴达木盆地地产育肥饲草料进行了营养成份分析,结果表明,柴达木盆地地产饲草料育肥家畜的日粮配方,与省内其他地区育肥家畜日粮配方的营养水平基本相当,只是磷含量较少,应适当增加磷比例。 相似文献
9.
论述了网络环境下,高校图书馆读者信息行为规律的变化及共性特征,并进行了实证分析研究。在此基础上,提出了图书馆多样化、多元化、个性化和一站式的信息服务管理策略。 相似文献
10.