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31.
以河南省濮阳市为例,介绍了远程教育终端防雷装置现状,分析了濮阳远程教育终端防雷装置存在的安全隐患,并对造成隐患的原因进行了深入调查与分析,进而就防雷管理工作提出了建议。 相似文献
32.
本文介绍移动计算环境下的广播策略,重点研究了使平均访问时间和调谐时间都达到比较理想值的LBCS法。 相似文献
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笔者通过RT-PCR方法对LMV北京分离物(LMV-BJ)基因组3'端1620nt的核苷酸片段进行了克隆和序列分析(GenBank登录号为EF423619)。所获片段含有NIb基因3'端的574nt,编码NIb C-端190个氨基酸;完整的CP基因,全长为834nt,编码一个由277个氨基酸组成的分子量约为30kDa的结构蛋白;3'非编码区含有209nt。通过序列分析软件将LMV-BJ与已经报道的法国分离物O(X97704)、法国分离物E(X97705),美国分离物(X65652),巴西分离物(AJ278854)和余杭分离物(AJ306288)基因组3'末端和CP基因的核苷酸序列与氨基酸序列分别进行了比较。 相似文献
34.
酒花的新根茎芽,产生于上年根茎芽的腋芽。所以从腋芽长成新根茎芽,再发育成年苗,要经历三个生长季,有三次分化高峰,分别在当年的春季和秋季,以及形成年出的春季,每次分化可形成10个节位左右。由营养苗端转化为生殖苗端时,生殖苗端伸长,原套层数增加,形成花序生长锥,可自下而上分化具有15~20个节的花序轴,每一节上均要经历外苞形成期,内苞形成期、花被形成期和雌蕊形成期。年苗顶芽在个体发育过程中,在不同的发育阶段,不同茎的粗度、其内部结构,包括节数,分化程度、侧芽的大小均有差異。 相似文献
35.
简要介绍了以UNIX为操作系统的SUN、SGI系列工程工作站及MC68000系统与以DOS为操作系统的PC机系统的互连,从而构成异型机及网间的互连通讯,达到数据共享,节省资源的目的。该方法实现简单,具有广泛的应用前景。 相似文献
36.
Low tillering lines of spring wheat ( Triticum aestivum L.), were evaluated for their ability to conform to a high yielding ideotype in a dryland environment with spring drought. The ideotype was based on a concept of saving water as a result of reduced canopy development before anthesis; this should improve moisture supply for grain filling, thus reducing the effect of drought.
Five genotypes were compared under two nitrogen (N) levels, and at similar plant densities, at a site in the drier wheatbelt area of southwestern Australia. The genotypes formed three tillering groups based on the maximum number of culms produced: a free tillering group (G1), which included the standard cultivar Gamenya , with 4.3 culms per plant, an intermediate tillering group (G2) with 3.2 culms per plant, and a low ullenng group (G3) with 2.4 culms per plant.
Leaf area indices (LAI) were strongly affected by N but this was not reflected in total water use and biological yield. However, water was prematurely depleted before anthesis as a result of rapid early leaf development in response to N, and this reduced grain yield. Reduced tillering produced no significant increase in gram yield over the controls; fewer tillers per plant failed to suppress LAI development and water-use before anthesis because of a compensating increase in LAI; this resulted from a greater leaf size in the reduced tillering lines. Hence the low tillering lines did not fully conform to the requirements of the ideotype.
The development of low tillering lines is seen as a significant advance towards the ideotype; with yields comparable to commercial cultivars grown in the region, their performance indicates a potential for substantially higher yields if compensating increases in leaf development can be suppressed. 相似文献
Five genotypes were compared under two nitrogen (N) levels, and at similar plant densities, at a site in the drier wheatbelt area of southwestern Australia. The genotypes formed three tillering groups based on the maximum number of culms produced: a free tillering group (G1), which included the standard cultivar Gamenya , with 4.3 culms per plant, an intermediate tillering group (G2) with 3.2 culms per plant, and a low ullenng group (G3) with 2.4 culms per plant.
Leaf area indices (LAI) were strongly affected by N but this was not reflected in total water use and biological yield. However, water was prematurely depleted before anthesis as a result of rapid early leaf development in response to N, and this reduced grain yield. Reduced tillering produced no significant increase in gram yield over the controls; fewer tillers per plant failed to suppress LAI development and water-use before anthesis because of a compensating increase in LAI; this resulted from a greater leaf size in the reduced tillering lines. Hence the low tillering lines did not fully conform to the requirements of the ideotype.
The development of low tillering lines is seen as a significant advance towards the ideotype; with yields comparable to commercial cultivars grown in the region, their performance indicates a potential for substantially higher yields if compensating increases in leaf development can be suppressed. 相似文献
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38.
云计算与移动数字图书馆 总被引:1,自引:0,他引:1
刘杨 《农业图书情报学刊》2012,24(4):56-59
移动数字图书馆作为图书馆在信息技术变革中推出的新服务模式,无疑会受到云计算技术的影响。通过分析云计算的特征和应用形式,提出移动数字图书馆应用云计算的三种模式,即基础设施即服务(IAAS)、软件即服务(SAAS)和平台即服务(PAAS)。 相似文献
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40.
基于移动通信的SMS、Mobile Web技术,开发林产品运输信息平台,可实现检尺员上传检尺短信后,实时采伐监控并加强运输监管。该平台有助于运输公司实现物流通知、空车配货,能提高服务质量,降低物流成本。系统架构成本、运营成本低,具有较强的市场竞争力。 相似文献