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101.
In this paper,the oscillation amplitude of the free end of a group of threecylinders are studied.The three cylinders are erected at the vertices of an equilateral trian-gle,and three arrangements are made in this study.One of the three cylinders is served asa working cylinder which is mounted by a flexible cantilever and two accelerometers areattached on the free end in two directions.The results of the three-cylinder arrangementare compared with those of two cylinders in tandem/side-by-side arrangement in the samecondition.The experimental results show that the rear cylinder of a group of three cylin-ders is affected more seriously than that of the corresponding two cylinders in the contrastarrangement.The main direction of oscillation is changed.The transversal oscillation isstronger than the longitudinal oscillation in the three-cylinder arrangement.On the con-trary,the transversal oscillation is much weaker than the longitudinal oscillation in two-cylinder arrangement.The largest transversal oscillat  相似文献   
102.
1MotivationsIncreasingdensityofVLSIchipsmakesthecostoftestingveryexpensive.Designfortestabilitycantemperthisproblemdrastically.Therearetwokindsofsolutions:(i)localsolutionl3'2]withlowcomputingcomplexity,whichcannotalwaysgetsatisfactoryresults;(ii)globa.lsolutionwithprohibitivecomputingcomplekityl1'5].T.H.Chen'andM.A.Breuer[1lpresentedanILPmodeltoplacetestpointsglobally.Becauseofitscomputingcomplealty,[1lcanonlydealwithsmallormediumscalecircuits.SCOAPisusedin[1],whichisnotaveryaccuratet…  相似文献   
103.
考虑非线性不确定系统的鲁棒吸引问题,借助于动态输出反馈,构造了两类控制律。这两类控制律分别可使相应的闭环系统被一任意小的区域鲁棒吸引,或被一预先设置的区域有限吸引。  相似文献   
104.
OBJECTIVE: To evaluate the therapeutical mechanism of Bushen Shengxue Paste (BSSXP) on anemia. METHODS: Chronic renal failure induced anemia patients were treated with BSSXP, clinical manifestation, anemia and renal function as indicators were observed in patients. The erythropoietin (EPO) and inhibition of colony-forming unit-erythrocyte (CFU-E) in patients' serum were determined by CFU-E in vitro. RESULTS: The patients' symptoms, renal function and anemia were improved after administration with BSSXP 1-2 course. EPO in serum was slightly increased. The inhibition of CFU-E in patient's serum was significantly decreased. CONCLUSIONS: BSSXP could improve the anemia degree, its mechanism might be through clearing the inhibitor of CFU-E in serum.  相似文献   
105.
For the first time, the surface metal on nonalloyed ohmic electrodes is found to significantly change the profiles of gate grooves, when resist openings are employed to monitor drain current during wet-chemical gate recess for sub-micron InAlAs/lnGaAs heterojunction field-effect transistors (HFETs). The surface metal of Ni enhances the etching rate in comparison with that in the absence of electrodes by a factor of 4 and 10, laterally and vertically, which is favorable to fabricate deep gate grooves with small side etching. The Pt surface metal, however, leads to preferential etching of InGaAs over InAlAs, which can be useful to realize large side etching. The existence of an electrochemistry-related etching component, which arises when the ohmic electrodes are present during recess etching, is considered to be responsible for these behaviors  相似文献   
106.
金属清净剂的性能研究   总被引:2,自引:0,他引:2  
为了改进金属清净剂的抗氧性和极压抗磨性能,用一种含硫磷的羧酸衍生物部分中和清净剂中过碱性组分,得到两种改进的金属清净剂,并用四球机和热重分析仪评价其极压抗磨和抗氧化性能。结果表明功能化处理提高了金属清净剂抗氧化和极压性能,但未对分散和抗磨性能产生显著影响。  相似文献   
107.
分布存储多机系统中的消息传递技术   总被引:9,自引:1,他引:8  
本文回顾了分布存储多机系统中消息传递技术几十年来的发展,介绍了现阶段消息传递技术的主要研究成果,例如wormhole寻径技术,虚通道流控制技术等。最后,对消息传递技术今后的研究方向作出了一些设想。  相似文献   
108.
中子产额大于1.5×10^10n/s的密封中子管   总被引:3,自引:3,他引:0  
董艾平  李文杰 《核技术》1995,18(6):338-342
报道了一种中子产额大于1.5×1010n/s、靶和离子源都可拆卸的密封中子管,以它为核心研制的密封中子发生器已被用于中子照像等领域,并取得了较好的结果。  相似文献   
109.
以三烷基磷酸酯络合硫氰酸钙为模型化合物研究了含硫氰基团的络合物的摩擦学行为,发现它有高的承载能力,良好的抗磨减摩性。用俄歇能谱(AES)、X-射线衍射(XRD)、扫描电镜(SEM)及X-射线能谱(EDX)研究了摩擦表面元素组成及其可能物相。探讨了摩擦化学机理,认为化合物中的硫氰基团对摩擦学性能起主要作用,并在摩擦过程中发生类似于化学热处理中的硫氰共渗。  相似文献   
110.
The growth of human leukemic cells in culture and in vivo is dependent upon the presence of hematopoietic growth factors. Most populations of human leukemic acute myeloblastic leukemia (AML) cells express c-Kit on their surface and respond to Kit ligand (KL) in culture. To determine if this interaction was of potential significance in vivo we used a mouse model system. 32D cells, a murine IL-3-dependent myeloid cell line, were rendered KL responsive by transfection of the murine c-Kit. After injection of 32D or 32D-Kit cells into syngeneic hosts, animals bearing 32D-Kit cells, but not 32D cells, became moribund and were killed. These animals had circulating leukemic blast cells, infiltration of bone marrow, spleen, brain, liver, lung, and kidney. Cells recovered from some of the animals continued to be dependent upon IL-3 or KL for growth while in other cases the cells were factor independent. This model illustrates that the constitutive expression of c-Kit enhances the leukemic potential of 32D cells. The model will be useful for studying the progression of leukemia in vivo and testing whether interruption of the interaction of Kit and KL can affect the growth of leukemic cells.  相似文献   
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