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911.
Using Neural Network to Predict the Interfacial Friction and Flow Stress of Materialsvia Ring Compre
Xu Weiliang 《东南大学学报》1996,(1)
UsingNeuralNetworktoPredicttheInterfacialFrictionandFlowStressofMaterialsviaRingCompressionXuWeiliang(徐卫良)(DepartmentofMecha... 相似文献
912.
William:Hello, John! How do you do? John:Hetlo, William! I am fine. William:What are you doing? John:I am reading an article. William:What is it about? Is it interesting? John:It is about the history of human beings, I find it quite interesting.William:History of human beings? Sounds very interesting and special. Can you tell me a little bit about it? 相似文献
913.
I feel that this award was not made to me as a man,but to mywork—a life's work in the agony and sweat of the human spirit,not for glory and least of all for profit,but to create out of thematerials of the human spirit something which did not exist before,sothis award is only mine in trust.It will not be difficult to fred a dedi-cation for the money part of it commensurate with the purpose andsignificance of its origin.But I would like to do the same with the ac-claim too,by using this moment as a pinnacle from which I might belistened to by the young men and women already dedicated to the same 相似文献
914.
一、惩罚的心理学分析惩罚,意指对犯有过错行为的人给予一种处罚。一般说来,惩罚是针对有意犯过的人的,就是他明知这种行动是错的,伹仍故意去做。对年幼儿童来说,除非确实知道他们已经懂得和学会了家长或教师教给他们的有关这方面的行为准则,否则的话,我们就不能断言,他们是故意去做这一越轨行为的。当然随着他们年龄的增长,可以肯定他们已经懂得是非好坏,因此可以认为,他们做的任何一个不正当举动都是有意的。这些说法并不总是正确的。儿童即使知道了一种规则,他们并不理解规则的全部意义,这是尽人皆知 相似文献
915.
吉姆.斯陶沃 《聪明泉(少儿版)》2005,(3)
一天,生活在山上的部落突然对生活在山下的部落发动了侵略,他们不仅抢夺了山下部落的大量财物,还绑架了一户人家的婴儿,并把他带回到山上。可是山下部落的人们不知道怎样才能爬到山上去。他们既不知道山上部落平时走的山道在哪里,也不知道到哪里去寻找山上的部落,甚至不知道如何去发现他们留下的踪迹。尽管如此,他们还是派出了他们部落中最优秀,最勇敢的战士,希望他们能够爬到山上去,找回孩子。 相似文献
916.
INTRODUCTION Photonic crystals (PhCs) are increasingly at- tracting attention due to their ability of controlling light propagation on a wavelength scale, by which a fascinating platform for a new generation of inte- grated optical devices and components can be pro- vided. Many studies on PhCs however, focused on new means of tailoring the emission and propagation of light using the photonic band gap (PBG) property whereby the photon density of states is zero. A PhC with a full PBG re… 相似文献
917.
918.
OGUNLEYE R.F. ADEFEMI S.O. 《Journal of Zhejiang University. Science. B》2007,8(12):912-916
Insecticidal effects of different doses of the dust and methanol extracts of Garcinia kolae on Callosobruchus maculatus and Sitophilus zeamais were tested. The dust had no significant effect on the two insects, none of them died even at 3 d after treatment. The methanol extracts, however, had rapid lethal effects on both C. maculatus and S. zeamais. The mortality of C. maculatus by the lowest concentration of methanol extracts ranged from 95%-100% whereas in S. zeamais, the mortality ranged from 87.5%-100% and 70%-100% in concentrations of 1 g extract+3 ml methanol and 1 g extract+5 ml methanol, respectively, from 24 to 48 h. The least concentration of 1 g extract+l 5 ml methanol had no significant lethal effect on Sitophilus zeamais. 相似文献
919.
Vacuum interrupter, high reliability component of distribution switches, circuit breakers and contactors 总被引:1,自引:0,他引:1
SLADE Paul G LI Wang-pei MAYO Stephen SMITH R. Kirkland TAYLOR Erik D 《浙江大学学报(A卷英文版)》2007,8(3):335-342
The use of vacuum interrupters(VIs)as the current interruption component for switches,circuit breakers,reclosers and contactors operating at distribution voltages has escalated since their introduction in the mid-1950’s.This electrical product has developed a dominating position for switching and protecting distribution circuits.VIs are even being introduced into switching products operating at transmission voltages.Among the reasons for the VI’s popularity are its compactness,its range of application,its low cost,its superb electrical and mechanical life and its ease of application.Its major advantage is its well-established reliability.In this paper we show how this reliability has been achieved by design,by mechanical life testing and by electrical performance testing.We introduce the“sealed for life”concept for the VI’s integrity.We discuss this in terms of what is meant by a practical leak rate for VIs with a life of over 30 years.We show that a simple high voltage withstand test is an easy and effective method for monitoring the long-term vacuum integrity.Finally we evaluate the need for routine inspection of this electrical product when it is used in adverse ambient environments. 相似文献
920.
AUDYJ. 《浙江大学学报(A卷英文版)》2006,7(11):1781-1789
INTRODUCTION Metal machining processes are characterised mainly by quick changes in quantified elements. In- dividual changes do not occur in isolation and they influence each other. The analysis of these changes require study of the complicated complete systems in their real situations. The study of cutting processes such as turning and facing, from dynamic aspects, is very important. The trend towards the measurement of cutting forces in machining leads to many theo- retical and practic… 相似文献