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991.
本文介绍利用Super Frame软件进行色彩浓淡设计的原理、方法和步骤。据此原理和方法,使用C语言设计开发出了应用实例——折线浓淡分布曲线。 相似文献
992.
993.
John E. Beard
Malcolm E. Wright
Michael MailanderMark Miller
《Mechanism and Machine Theory》1992,27(6):635-644The design of a specialized agricultural harvesting machine required the use of a path generation mechanism that was compact, accurate, inexpensive to manufacture and difficult attempts involved the use of a cam and follower, but they were expensive to manufacture and difficult to operate. This paper discusses an alternative method of using a coupled, open loop, two-link mechanism to generate a polygon-like closed path (pseudo-polygon) with an integer number of curved sides and apexes. A complete development of the path and path curvaturei equations are presented. The influence of the design variables on the coupler shape (flatness of each side) is shown in equation and design chart form. An example of a successful application of this design method applied to a plant cutting mechanism is presented. 相似文献
994.
George Chryssolouris James E. Pierce Kristian Dicke 《International Journal of Flexible Manufacturing Systems》1992,4(3-4):309-330
This paper introduces a generic decision-making framework for assigning resources of a manufacturing system to production tasks. Resources are broadly defined production units, such as machines, human operators, or material handling vehicles; and tasks are activities performed by resources. In the specific context of FMS, resources correspond to individual machines; tasks correspond to operations to be performed on parts. The framework assumes a hierarchical structure of the system and calls for the execution of four consecutive steps to make a decision for the assignment of a resource to a task. These steps are 1) establishment of decision-making criteria, 2) formation of alternative assignments, 3) estimation of the consequences of the assignments, and 4) selection of the best alternative assignment. This framework has been applied to an existing FMS as an operational policy that decides what task will be executed on which resource of this FMS. Simulation runs provide some initial results of the application of this policy. It is shown that the policy provides flexibility in terms of system performance and computational effort. 相似文献
995.
汽车燃料质量发展新趋势 总被引:1,自引:0,他引:1
从现在到21世纪初,汽车燃料质量主要按照减少排气污染的思路来设计。汽油和柴油的发展趋势是:低硫、低芳烃、低90%馏出温度和高清净性。 相似文献
996.
A thermodynamic evaluation of the Fe-Cr-V-C system 总被引:2,自引:0,他引:2
997.
Jun Xiang Ge Si Fan Li Yi Yuan Chen 《Journal of Infrared, Millimeter and Terahertz Waves》1991,12(7):811-818
In this paper, a new kind of solid-state quasi-optical power combiner is presented. It consists of two or more singlecavity multiple-device power combiners and a Fabry-Perot cavity. The experimenal results using six Gunn diodes at X-band show that the total output power is higher than 400 mW, the total combining efficiency is as high as 83%, and the frequency stability is better than 10?5. 相似文献
998.
999.
聚氧化乙烯—聚磷酸钠共混物的钠离子导电性 总被引:1,自引:0,他引:1
研究了聚氧化乙烯-聚磷酸钠共混物的钠离子导电性和低分子量多缩乙二醇对共混物导电性的改进作用。结果表明,降低多缩乙二醇的分子量以及增加其含量都有利于提高共混物的离子导电率。增塑剂改进共混物导电性的实质是提高共混物的非晶相含量,共混物内钠离子传导发生在非晶区,聚合物链段运动是离子传导的主要推动力。 相似文献
1000.
T. -Y. Chen 《Structural and Multidisciplinary Optimization》1992,4(3-4):179-185
A design optimization procedure using a sequential linear programming technique is proposed in this paper to design minimum weight structures subjected to frequency response and static displacement constraints. The merit of the proposed approach is that the reanalyses of the static and dynamic responses, as well as the computations of the static and dynamic sensitivity data, are performed in a reduced approximate model. A significant saving of computer time for large scale structures is expected. Two numerical examples show good results of this method. 相似文献