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91.
92.
玉米种衣剂配方数学模型筛选研究 总被引:2,自引:0,他引:2
采用二次回归旋转组合设计方法 ,对玉米种衣剂优化配方进行研究。通过利用计算机技术对试验数据进行处理和模拟寻优 ,建立了产量函数模型 ,筛选出产量≥ 975 0kg hm2 的最佳配方组合方案 ,并确定了置信域。 相似文献
93.
宁南旱区苜蓿草地土壤水分消耗规律及粮草轮作土壤水分恢复效应研究 总被引:9,自引:0,他引:9
对宁南旱区不同生长年限紫花苜蓿草地土壤水分消耗及粮草轮作水分恢复效应进行了研究。结果表明:(1)随着苜蓿生长年限延长,在1 ̄6年内苜蓿草地土壤湿度下降迅速,产草量逐年上升,7年后土壤湿度下降趋于平缓,但苜蓿产草量下降迅速,表明苜蓿生长强烈耗水引起深层土壤干燥化,导致苜蓿生长逐渐衰败,苜蓿平均降水生产效率逐年下降;(2)苜蓿草地土壤垂直剖面可分为降水入渗恢复层(0 ̄200cm)、根系发达枯竭层(200 ̄500cm)和根系衰老缓耗层(500cm以下)三个层次。随苜蓿生长年限延长,苜蓿剖面的主要土壤干层逐渐上移,并且干层厚度呈现减小趋势;(3)耕翻的苜蓿茬后轮作粮食作物的年份越长,土壤水分恢复越好,实行草粮轮作的苜蓿最迟不超过生长的第10年。 相似文献
94.
95.
YANG Xue-heng CHEN An HE Guang-hong FENG Xiao-juan WANG Ying-fang ZHAN Jie TANG Zhi-liang 《保鲜与加工》2001,(3):137-141
Some ideas are given about using out-clock, CPU and anti-T-net of D/A card for getting to the intelligent control of scanning voltage ,low-filter and hign-filter of STM; logarithm amplifier for tunnelling current contraction. At last, some applications and questions when it running about STM are discussed. 相似文献
96.
Aero-elastic model design is the precondition of full bridge aero-elastic model tunnel tests. The full aero-elastic bridge model design of long span arch bridge is discussed. The effect on the model design of different transverse rod space and bend stiff is analyzed in detail. Different scheme need to be designed according to the transverse rod stiff. Considering the changing section dimensional arches, the method of projecting the spatial arches to the plane arches, then designing the plane arches, at last projecting the plane arches to the spatial arches is proposed at first. The results show that the method is effective. 相似文献
97.
Considering the difficult of acquiring and transmission the signal from the moving equipment, a new fault diagnosis monitoring system is presented. The system acquires the state signal from the moving equipment by data acquisition module that based in W77E58 high-speed SCM, and transmits the data fast by wireless mode. The signal data can be use for fault diagnosis and precise analysis. The system has the ability for acquiring abundance of data with a high speed, the ability for high accuracy data conversion, and has a function of programme controlling gain and programme controlling low-pass filtering. The successful application of this system on the vibration monitor about the material-transporting bogie in an iron works of a domestic steel enterprise proves the stability and credibility about the design project, also testifies its practical value and versatility. 相似文献
98.
In urban design, only by continuous and dynamic research work from design to finally putting it into practice, can we made good control on city appearance. This article analyzes nowadays defects in our urban design from two aspects as the result establishment and validated control, and tries to conceive a feasibility plan to solve the problem. 相似文献
99.
According to the needs of setting up a professional system based on motorcycle design,the CBR(case based reasoning) and RBR(rule based reasoning) methods are introduced.After discussing the difference between the two kinds of reasoning,a method of integrating them into the motorcycle design flow is put forward to realize the design reusable technology and improve the design efficiency,by using the CBR in the step of selecting the similar motorcycle and the RBR in project's modification according to correlative rules. 相似文献
100.
LI Shao bin 《保鲜与加工》2002,(4):29
To research the problem of plastic art design and emulation of products with the virtual reality technology can short the product development cycle and reduce the cost. This paper discusses the information based on the product feature ,solid model with parameters, the structure and function of this system. Combined the product properties with its solid model. Proposed a method with CAD to create the model of the product based on features in the product design. Expressed its feature parameter and shape of model fully .In the case for a deceleration box the feature model has solved the problem of physical information ,geometry information and the informative process in its production management system efficiently. 相似文献