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排序方式: 共有3093条查询结果,搜索用时 8 毫秒
31.
Some new concepts of coneD_s convexity,coneD-s quasiconvexity,cone D-s pseudoconvexity,s right derivative of vector value mapping are proposed;and their related properties are discussed;the optimality necessary conditions and sufficient conditions for constrained extremum problem(VP)involving in cone D-s convex mapping are extablished;the relation between local optimal solution and global optimal solution;as well as the relation between weakly efficient solution and efficient solution for (VP) are derived;the corresponding results generalize the related results of classic convex programming. 相似文献
32.
Zhang Shiqing 《保鲜与加工》1996,(6):96-103
This paper generalizes all known results on Rabinowitz's minimal periodic solution conjecture under the assumption that Hamiltonian function is C2 strictly convex. 相似文献
33.
Li Maoqin Duan Yurong 《保鲜与加工》1989,(4):22-29
In this paper, a kind of grey linear programming with grey interval coefficients is discussed,the definitions of the first and second whitenized linear programmlngs and the grey dual linear programmings are presented, the relationships between the solutions of the above three kinds of programming and the solution of the primal programming are explored, and some new conclusions are obtained. 相似文献
34.
Zhang Hongjing Zhou Zhaoyi 《保鲜与加工》1997,(2):123-127
This paper presents a detail study of bubble coalescence in inorganic salts and organic compounds of fermented solution ,and preliminary analyses the principle of bubble coalescence.The experiments show that the relationship between the solute concentration and coalescence frequency reveals the existence of sharp transition concentration. 相似文献
35.
TAN Jun Yu 《保鲜与加工》2001,(5):145-148
A class of analytic solution for RLW Burgers equation and KdV Burgers equation are given which include results of some papers.These solutions can be expressed as some linear combination of solutions of Burgers equation and RLW equation or KdV equation which correct conclusion in some paper. 相似文献
36.
37.
Zou Jianbo 《保鲜与加工》1992,(4)
In this paper, the concept of basic for linear vector extreme value problem is introduced in the partially ordered vector space. Some properties and results of the linear programming are generalized. And the existaence therom of basic optimal solution is proved. 相似文献
38.
This paper designed and developed a multi-objective programming (MOP) model to illustrate the dynamic relationship among technologies, productive activities, constraints and farmers’ objectives in the peri-urban vegetable production system and use the model as an economic tool in analysing probable consequences of a given action or innovation on the farm. The best compromise solution was generated using four analytical steps, as follows: single-objective optimization (to determine the ideal and anti-ideal values of the objective functions); constrained optimization (to generate the set of Pareto non-dominated solutions); cluster analysis (to trim down efficient set into smaller homogeneous groups); and compromise programming (to determine where the best compromise solution lies). 相似文献
39.
棉田膜内与膜间土壤溶液含盐量的变化 总被引:1,自引:0,他引:1
用定期取表层土样测定其电导率和在不同深度埋设盐分传感器探头的方法 ,在作物生长季节内 ,监测了棉田膜内和膜间不同深度的土壤溶液含盐量变化。结果为 :1棉田膜内与膜间表层土壤和 1 0 cm、30 cm深土壤溶液含盐量变化较大 ,且规律相同。未灌水时上升 ,灌水后迅速下降。膜间未灌水期间的含盐量上升幅度大于膜内 ,灌水对膜内和膜间表土洗盐、1 0 cm、30 cm深土壤溶液含盐量的降低作用没有差别。降雨可引起膜内和膜间 1 0 cm深土壤溶液电导率的变化 ,这个影响也是膜间大于膜内。 2 60 cm深的土壤溶液不存在明显的盐分累积现象 ,灌水可使这里的土壤溶液含盐量缓慢降低 ,膜间的降低过程快于膜内 相似文献
40.