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春小麦优良变异类型的选择参数—协调指数 总被引:1,自引:1,他引:0
用分形理论的思想 ,对小麦分离与不分离群体内各单株性状组合特征进行系统分析 ,在不改变性状表达程度与群体分布状态的前提下 ,根据各单株的每一性状占各自群体最大值的比例数 ,及各比例数大小序号 ,求二者间双对数的回归斜率 ,作为该单株性状组合的协调指数。结果表明 ,该指数小 ,表示本单株各性状在表达程度上接近 ,说明性状间关系比较协调 ,否则即不协调。 相似文献
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枯草芽孢杆菌B—916防治水稻纹枯病的田间试验 总被引:35,自引:4,他引:35
1992~1994年在田间小区试验比较两个拮抗细菌(B-916、P-91)和井岗霉素对水稻纹枯病的防治效果。1994~1995年在江苏省3个基点上进行了B-916防治纹枯病的大面积示范试验。B-916发酵液在田间对水稻纹枯病的为害有较强的控制能力,发酵含菌量为2.54×1011~2.54×1012cfu/mL时,用量3.75L/hm2的防治效果为50.0%~81.0%。 相似文献
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The traditional scheduling for vehicle is option in the fixed network. But it can't satisfy the real time environment. The demand of order is changeable and uncertain in real environment. It is convenient for scheduling transforming it into static data, but can't get the advantage on time. This paper proposes a real time vehicle scheduling on the study of traditional scheduling and discusses the model structure and the key technology for the real time system that establishes the base for develop teal time system. 相似文献
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Aiming at knowledge representation problem of expert system for rotary machinery fault diagnosis, semantic net knowledge representation is discussed. Semantic net to represent expert knowledge of rotary machinery fault diagnosis is explored. Its realizing method is afforded in computer language, in addition, demostrating model is also developed in Visual C++. The result shows good validity of the knowledge representation. 相似文献
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Data warehouse is not the simply data accumulation of operational database. For exerting the function of data warehouse, the construction of data warehouse should be convenient for the data mining and business intelligent work, supply information access, analyze, and share for decision maker. The key to constructing a successful data warehouse is to fully understand the demand of end users from beginning to the end, search and storage data surround users motive closely. This paper first analyzes the data warehouse characteristic and the sort of data component, emphasizes in effective data loading methods and strategies from operational database to data warehouse, gives five sorts data loading methods. 相似文献
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Such the geological hazards as landslide, rockfall, debris-flow and so on frequently occur in the Three Gorges Reservoir Area, so it is a very practical and immediate job to explore the mechanism caused the geological hazards and how to forecast and control the geological hazards. For this reason, this paper introduces the situation of the geological hazards occurred in the Three Gorges Reservoir Area and the major type and feature of the geological hazards occurred in Chongqing, and discusses the basic principle about the modern nonlinear science applied to the geological hazards and the creep-slip, stick-slip occurred on the joints of rock mass and the monitoring technology of the geological hazards.The basic thinking is put forward which can be applied the modern nonlinear science to the geological hazards occurred in the Three Gorges Reservoir Area. 相似文献
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