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891.
In this paper the working principle and performance character of both the manual and automatic Vicat apparatuses in existence are compared and analyzed,and their existing weakness and the urgent problem to be solved are pointed out.On this basis,adopting the technology of mechatronics and modern sensors,a new sort of full automatic Vicat apparatus that can fully satisfy the national standard in testing the setting time of the cement has been developed.This apparatus can be operated expediently with high precision,the test results are to be analyzed and computed automatically.This paper presents the working principle,performance character,key technology and prospect of application for the full automatic Vicat apparatus. 相似文献
892.
In this paper, according to the study on a great number of experiments and data analyses, the sedimentation rule of solid particles in debris flow is set up. Three main factors that influence the particle sedimentation in debris flow were studied; the basic reasons to influence the particle sedimentation were analyzed. The particle sedimentation in debris flow could be divided into three stages,i, e. the starting stage, the quick sedimentation stage and the accumulation stage,and detailed analysis on the sedimentation process each stage was made. The liquid viscosity, particle quality and additional water pressure have an important role on the sedimentation rule of the particle in debris flow. 相似文献
893.
894.
895.
The datum line and mainly three profile height parameters of surface roughness are briefly introduced and the operation principle and system structure of AFM. IPC - 208B with high-resolution, which was successfully developed by Chongqing University, are described in detail, and the emphasis is laid on its application on the nanometer scale surface roughness. Taking stainless steel for example, its micro-structure was observed, and the surface data were analyzed and transacted by special evaluator and the values of three profile height parameters were obtained. Finally the experimental results are briefly analyzed. 相似文献
896.
Grid applications have evolved from science research to business and manufacture field, in these fields, tasks always process in workflow mode. In order to found a workflow management system in grid , the authors adopt a hybrid grid workflow engine after analyzing the characteristics of grid environment and give a referenced model of workflow management system in grid that is based on the engine. Through the examination, the authors prove the original intention is feasible. 相似文献
897.
For the inequality constrained nonlinear programming problem, the antnors propose a new lower order penalty function, which combines the classical l1 penalty function and the lower order exact penalty function introduced in thoy some papers, and then illustrate that it has the merits of the two penalty functions. In additional, we propose a solution method for solving the inequality constrained nonlinear programming problem and prove its global convergence. 相似文献
898.
余庆地瓜1号的选育与利用 总被引:1,自引:1,他引:1
贵州省余庆县种植地瓜有上百年的历史,以生产种子为主。目前,常年种子生产种植面积达73~133hm^2,年产种子150~300t,远销全省及周边地区。1988~1996年从当地种植的地瓜中选择变异株,经系统选育而成的新品种余庆地瓜,表现植株生长势较强、抗病、早熟、丰产性好;块根圆锥形或扁圆形,皮薄易剥、味甜、纤维少易化渣等特点。块根采收期110~150d,产量2400~4500kg/667m^2。2006年2月通过贵州省农作物品种审定委员会审定,并定名余庆地瓜1号。 相似文献
899.
900.
According to a new trend of telerobot control, some key techniues are researched to solve the Internet telerobotics , such as distributed intelligent computation on the Internet, human-computer interface,and Internet-robot interface etc.The current development status of the Internet telerobotics is reviewed. Based on the new directions of the network software development, the authors discuss that the middleware technique CORBA plays an important role in solving the problems of the Internet telerobotics,and it is an effective way to use Java language to control the telerobot and improve its system performance. The application perspective of the Internet telerobotics is investigated.It is indicated that the development trend of the telerobot control is a human-centred collaboration mechanism of mutual reinforce and coordination in human-machine intelligent. 相似文献