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1.
棉花适宜叶面积指数的动态知识模型   总被引:10,自引:3,他引:10  
通过分析和提炼棉花叶面积指数的最新研究资料,在综合考虑目标产量、种植密度、生态条件和生产水平等影响因子的基础上,运用知识工程和系统建模方法,建立了棉花叶面积指数动态模型。利用不同产量目标、不同种植密度、不同生态点和不同品种等试验资料对模型进行了验证,结果表明模型具有较强的可靠性和适用性。  相似文献   

2.
基于知识模型和GIS的棉花生产潜力评价系统   总被引:9,自引:2,他引:9  
引入知识模型概念,建立以棉花生产潜力知识模型为特征的知识系统,将知识工程和数据库有机结合,以 Mapinfo 5.5 为系统开发平台,利用 MapBasic和 Visual Basic程序设计语言,建立基于知识模型的棉花生产潜力评价系统,实现棉花生产潜力评价的计算机辅助决策。应用本系统对江苏地区棉花生产潜力进行实例评价,并与实际单产相比较,进行单产潜力、潜力系数和总产潜力的对比分析,确定棉花生产地域优势。  相似文献   

3.
knowledge management is an effective method to improve the enterprise's competitive ability. To construct knowledge system is the base for the performance of knowledge management. According to the theory and method of system engineering, information system and information management, this paper gives an architecture of enterprise knowledge management system basing on management information system. The architecture includes several main parts, such as knowledge base, knowledge base management system, people for knowledge management and users. A function structure of knowledge management system is given too.  相似文献   

4.
棉花适宜密度与播种量设计的动态知识模型   总被引:4,自引:1,他引:3  
通过分析和提炼有关棉花种植密度与播种量的最新研究资料,在综合量化气候条件、土壤类型、产量目标、管理水平和品种特性等影响因子的基础上,建立了具有时空适应性的棉花种植密度和播种量设计动态知识模型,可用于精确定量不同环境和不同产量目标下的种植密度和播种量。利用不同生态点、不同品种、不同土壤类型和不同产量目标等资料对知识模型进行了验证,结果表明模型具有较好的决策性和适用性。  相似文献   

5.
棉花产量目标和产量结构的动态知识模型   总被引:3,自引:3,他引:3  
通过分析和提炼棉花皮棉产量及产量结构的最新研究资料,在综合考虑气候条件、土壤肥力和栽培技术水平等影响因子的基础上,建立了棉花产量目标和产量结构的动态知识模型。该模型可用于精确定量不同气候条件、不同土壤肥力和不同栽培技术条件下的产量目标以及基于品种特性的产量结构。利用不同生态点资料对知识模型进行了验证,结果表明模型具有较好的决策性和适用性。  相似文献   

6.
The same CRM solution in same industry results in service assimilation among businesses, the cost of customer retention are rising, such strategy can not serve the purpose of saving customer cost for companies. This article introduces the new CRM solution- CKM, then analyzes the information from customer to company through the process that company dealing with consumer, and proposes a solution of the five styles CKM.  相似文献   

7.
科研机构是知识创新型单位,是知识密集型组织,科研机构的绝大多数产出与知识管理密切相关。由于人们理解的角度和范围不同,对农业科研机构的知识管理的认识也存在着不同的解释。本文探讨了农业科研机构知识管理研究的背景、必要性以及基本内容,认为农业科研机构的知识管理的核心在于隐性知识的显性化。这对于正确理解知识管理实务和构建农业科研机构的知识管理理论体系具有重要指导意义。  相似文献   

8.
VaR model is one of methods to measure and control market risk.This paper analyzes VaR model principle and its main factors.According to function relation,the relationship between the portfolio value and its market risk factors are sorted in two kinds: linear and nonlinear.The method of calculating the VaR is put forward.Finally,the article analyzes the application of VaR model to portfolio,risk control,information disclosure and financial supervison.  相似文献   

9.
From the point of view of Knowledge-based Engineering, the knowledge expression, the knowledge organizing format, the knowledge base and management system is researched aiming at the characteristic of motor total design and the knowledge. The knowledge of motor concept design is expressed and organized by Object Oriented method, and the blocking knowledge base is built. Base on the academic research, the Object Oriented knowledge base and its management system for motor intelligent design platform are developed. The result indicates this knowledge base can effectively express the motorcycle knowledge, and make reasoning simply.  相似文献   

10.
Concept of stability is vague, but it is basic characteristic of dynamic system, and precondition that make all kinds of control system run normally. Today it is still a challenge to analyze stability for uncertainty complex control system, whose mathematic modeling is impossible or very difficult, so it is very hard to judge whether a system running is stable or not by mathematic stability criterion. A kind of analyzing method is presented, which combine absolute stability with self-locked concept of heuristic search, it may analyze system stability in more range through adjusting self-collected loop parameters for uncertain control system based on knowledge control model. It is shown that stability analyzing method is effective and suitable for practical physical system in the engineering project.  相似文献   

11.
为了满足现代农业气象业务服务的需求,为各级政府决策部门和农业生产者及时、合理地开展田间管理和农业生产提供科学依据,在江苏省农科院研发的油菜发育期预报模型的基础上,利用安徽省1982~2005年甘蓝型油菜发育期资料和相对应的气象资料,运用数理统计方法,建立了安徽省油菜主要发育期区域预报模型;并依据天气预报,预测油菜开花期和成熟期。经模拟回代、试报和业务应用,结果显示:油菜开花期和成熟收获期实际观测值与模拟值的相关系数在0.8~0.9,平均绝对误差在2~3天;2006-2009年试报结果与实际值的绝对误差平均在3天左右。本研究对预测安徽省油菜的生育期进程提供了理论支持,并在2011年业务应用中效果较好,完全可以满足业务需求。  相似文献   

12.
氮肥运筹模式对小麦茎秆抗倒性能的影响   总被引:29,自引:0,他引:29  
以高产强筋小麦品种烟农19为试验材料, 通过不同施氮水平(202.5、270.0和337.5 kg hm-2)和不同基追比例的施肥试验, 对小麦茎秆结构和细胞壁化学成分及茎秆抗倒指数(CLRI, 茎秆机械强度/茎秆重心高度)等生理生化指标进行了研究。结果表明, 氮肥运筹模式显著影响小麦茎秆抗倒能力。基部节间长度和含氮量均随施氮水平和基肥比例的增加而增加, 基部节间粗度、秆壁厚度、节间充实度、机械强度则表现相反。而细胞壁纤维素、木质素含量和CLRI则随施氮水平的增加呈现出先增后降的趋势, 但随基肥比例的增加而下降。CLRI与基部节间粗度、壁厚、充实度及机械强度呈极显著正相关, 而与基部节间长度和氮含量呈极显著负相关。CLRI可作为小麦抗茎倒伏能力的综合评价指标。  相似文献   

13.
为了分析全球转基因玉米研究的热点与趋势,基于文献计量法,以Web of Science数据库核心期刊收录的2005—2015年间转基因玉米研究的文献为样本,利用Citespace软件对转基因玉米研究的科学知识图谱进行可视化分析。通过检索式检索,符合要求的文献共2851篇,经过排重筛选后为2701篇,文献量整体趋势呈平稳状态且有上升趋势。通过Citespace软件绘制关于学者合作网络、机构合作网络、文献共被引分析、作者共被引分析及关键词共现网络的科学知识图谱。通过聚类分析发现中国科研学者与机构在转基因玉米研究中占据数量优势,但是在引文被引方面,外国学者及其文章的重要性高于中国的学者及其文章。另外,全球转基因玉米研究热点主要围绕菌群、基因、蛋白质、稳定性等方面。  相似文献   

14.
WEPP模型中的CLIGEN与BPCDG应用对比研究   总被引:9,自引:0,他引:9  
通过对遂宁组紫色土产流、产沙侵蚀的观测,运用迄今为止最为复杂的土壤侵蚀预测模型WEPP模型进行单次降雨侵蚀预测,与实测值比较,并对比通过气候生成器CLIGEN和断点生成器BPCDG的产生的气候参数对预测值的影响。通过分析比较结果,认为WEPP模型对遂宁组紫色土侵蚀过程预测合理,而且利用断点生成器BPCDG的预测结果要优于气候生成器CLIGEN的预测结果。  相似文献   

15.
提出了以非线性函数拟合发展趋势、正弦函数逼近周期变动和马尔可夫链刻画随机扰动的集成预测模型,并利用该模型对福建省建阳市森林火灾面积的变动规律进行了预测预报,取得了较为理想的效果。理论与实践表明集成预测模型能定量分析灾害发生的时间动态及其变化规律,从而为灾害防御决策提供了可靠的信息。  相似文献   

16.
The characteristics of the knowledge discovery for basic oxygen furnace(BOF) steelmaking are analyzed by using the Rough Set Theory. The production data of BOF steelmaking are preprocessed by using the methods of data withdrawal, standardization, discretization and so on. The main influencing factors of steelmaking production are set as the knowledge discovery property. The endpoint control objectives of BOF steelmaking are used as the decision attribute of knowledge discovery. Then the knowledge discovery model of BOF steelmaking based on rough set theory is established, which makes the automation of the production knowledge discovery, access and rule extraction come true. The model is tested by using the production data of 210 t BOF, and takes the temperature variation of smelting endpoint as the decision attribute. The results show that the influencing factors, such as silicon content, iron ore weight, oxygen consumption and so on, are of very importance to the endpoint temperature of molten steel. Besides, the rules of molten steel temperature extracted by the model vary with current converter steelmaking process, which proves the validity of the model.  相似文献   

17.
水地小麦高产施肥模型及其应用研究   总被引:7,自引:0,他引:7  
采用三因素二次回归旋转组合设计方法,对影响小麦产量的氮肥、磷肥、有机肥的用量进行了定量研究,建立了中等以上肥力的水地小麦产量形成的施肥函数模型及最佳施肥组合方案,并确定水地小麦施肥模型主因素作用效应顺序:磷肥>氮肥>有机肥.还研究了各项施肥措施间的交互作用效应.  相似文献   

18.
The implement of enterprise knowledge management gives rise to extensive research on its measurement. Based on the existing measurement theories and evaluation index systems of enterprise knowledge management during the past three years in China, this paper analyzes the problems in measuring target and designing the evaluation index system in the existing research findings, and explains detailedly why measurement target of enterprise knowledge management should be "level evaluation" instead of "performance evaluation", and definitely points out the meanings of enterprise knowledge management level and significance of its evaluation. This paper also indicates that the design of the evaluation index system should be complete, reasonable, proper and operable.  相似文献   

19.
植物已知品种(以下简称“已知品种”)数据库是以品种性状描述、图像和DNA指纹图谱信息为核心,有效整合品种命名、审(鉴)定、保护、推广、转让、培育、栽培、繁殖、保藏等管理和技术信息,模仿人为判定过程,实现自动命名审查和近似品种筛选的高级专家系统。已知品种数据库基于网络环境设计,具有高度的共享性,可以大大提高品种保护、审(鉴)定、种子检测等管理部门的信息交流效率,是农业行政主管部门监控种子质量、维护市场秩序的重要技术支撑。已知品种数据库还可以为种子企业或育种者挑选品种、制定育种目标提供重要参考,节省社会成本。为此,通过对国内外植物品种管理信息系统进行研究,指出植物品种信息管理所应包括的基本内容和功能,得出中国已知品种数据库构建方法。  相似文献   

20.
In the last decade, with the development of environmental science, the studies on water quality models have developed rapidly at home and abroad. The water quality models are mainly used for simulating, assessing and predicting water quality and expounding the transport and transformation of pollutants in aquatic environment, the common models in literature such as fugacity approach, transport model of pollutants in multimedia environment, pollutant exposure model, and water quality management model and so on are discussed. The current situation, history and future trend of the research on aquatic environmental model are summarized. The theories, methodology and application problems which are involved with in this field are analyzed. Several leading objects for study are advanced also in this paper.  相似文献   

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