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51.
The scheme and practice for construct of intelligent agricultural information network are descibed . With Internet form, we set up the computer network of Intelligent Information Technology of Agriculture in Demonstration Section of Chongqing, discussed the design method of expert system in agriculture, and studied 5 expert systems based on vegetable growth, such as tomato and so on. Some software modules are studied, such as the soil information systems on the network, expert system in the vegetable plant diseases and insect pests diagnostician and network on line selling and so on. The structure,function and work flow of information service system based network are introduced. 相似文献
52.
The controlling and measurement system of pulse xenon lumps adopts high precision L C constant current charger, which can charge the storage energy capacitors with high repetition precision and communicate with computer real time. The system adopts quantification transforming model to measure the signals, which can reduce the interference and distortion. The multi tenors working model, which is used in computer controlling system, realizes the controlling and detection real time. 相似文献
53.
the foundation of Intelligent Information Technology of Agriculture in Demonstration Section of ChongQing,and the mostly research contents of the system of vegetable growth,and so on.On the base of radiation effect of demonstration section,the authors makes use of modern information technology,which can greatly expedite the extension and application of Agriculture information technology. 相似文献
54.
For the typical C V Algorithm, there exists the weakness of requiring multi iterative operations and long time computation to deal with large size image. Based on the analysis upon the relationship between the image size and the initialized approaching image with the number of iterations and computing time to obtain the stead results, an improved local C V image divisional algorithm based on the segmentation of threshold value and the connected domain labeled algorithm to deal with large size image is proposed. The OTSU method is used to divide the threshold value of image to reach the goal of label and local segmentation of image through the fast non recursion algorithm of connected domains. The segmented pieces and the result of its segmentation are used as the initialized approaching image of the C V algorithm model. Compared with the classical C V algorithm, the analysis and simulated result indicates that the improved C V algorithm reaches the steady solution quickly with fewer times of iterations. The proposed method can handle large size image with profound contour details quickly and effectively. 相似文献
55.
为了探明云南元阳梯田昆虫群落物种多样性,进一步明确不同生物多样性指数在较大空间尺度多样性评价中的应用,于2007—2008年,采用黑光灯诱集法对元阳梯田昆虫群落进行调查,运用可识别分类单元法进行昆虫群落物种快速分类鉴定,并对比Simpson指数、Shannon指数、Fisher多样性参数α和群落中性理论多样性参数θ对元阳梯田黑光灯诱集主要昆虫群落多样性评价间的差异。结果表明:(1)元阳梯田黑光灯诱集的昆虫群落物种较丰富,2007年和2008年分别诱集昆虫14目539种12460头和12目576种20920头。(2)Fisher多样性参数α和中性理论多样性参数θ的区分度较高,且对该区域黑光灯诱集的鳞翅目、鞘翅目和膜翅目昆虫群落物种多样性评价结果较相似。而Simpson和Shannon指数的区分度较低,对该区域内黑光灯诱集的主要昆虫群落多样性评价结果与其他多样性参数的评价结果不完全一致,甚至Simpson和Shannon指数的评价结果间相互矛盾。由此表明,Fisher多样性参数α和中性理论多样性参数θ更适用于黑光灯诱集的大尺度昆虫群落物种多样性评价。 相似文献
56.
固体超强酸催化合成聚合松香的研究 总被引:17,自引:9,他引:8
采用自制的SO4^2-/MxOy型超和作松香聚合催化剂。论文对影响反应过程的主要因素进行探讨。优化的工艺条件,固体超强酸用量5 ̄10%。反应时间3 ̄5h,反应温度110 ̄130℃,溶剂比1:1 ̄2,可获得符合标准要求的115牌号的聚合松香产品。 相似文献
57.
This paper proposes an improvement for the traditional Optical Algorithm, and presents a new way to image segmentation in a complex background. In addition, combined with the neural network, the system can locate the possible human faces successfully by means of two-step location model. In our system, the searching and locating of the human face is the most important stage. According to this, the authors adopt the two-step way to run, firstly they take up the segmentation of the candidate human face areas and then the accurate face locating based on the neural network is used. This algorithm is fast and robust. Experimental results with real scene images are given out there, and all these prove that two-step method gains many advantages in the course of human face location with motion information, such as real-time, robustness and practicality. In addition, the proposed system is also the fundamental and important part of the perfect human face recognition system. 相似文献
58.
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60.
亚麻抗枯萎病基因FuJ7(t)的分子标记 总被引:22,自引:1,他引:22
用高抗枯萎病亚麻品种“晋亚 7号”与高感枯萎病品种“晋亚 1号”配制杂交组合 ,接种鉴定其正反交F1代以及F2 代分离群体的枯萎病发生情况 ,结果表明 ,晋亚 7号对枯萎病的抗性属于细胞核遗传 ,受 2个显性基因控制。用 4 8个EcoRI/MseI引物组合对“晋亚 7号”、“晋亚 1号”两个亲本及其F2 代抗病和感病基因池进行AFLP分析 ,共扩增出约 330 0条可分辨的带 ,其中 3条为稳定的差异。用“晋亚 7号”和“晋亚 1号”杂交产生的F2 代分离群体对 3个特异条带与目的基因的遗传连锁性进行分析 ,发现特异条带AG/CAG与暂定名为FuJ7(t)的抗枯萎病基因紧密连锁 ,二者之间的遗传距离为 5 .2cM。将AG/CAG片段回收、克隆和测序 ,成功地将其转化为SCAR标记 ,可以更加方便地用于对FuJ7(t)基因的分子检测和标记辅助选择。 相似文献