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81.
The fabrication of small-scale electronics usually involves the integration of different functional materials. The electronic states at the nanoscale interface ...  相似文献   
82.
The highly integrated and miniaturized next-generation electronic products call for high-performance electromagnetic interfer?ence (EMI) shielding materials to ...  相似文献   
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We investigated the cantilevered carbon-nanotube-resonator including electromigratively movable nanoparticle via classical molecular dynamics simulations and continuum model. The change of the effective mass value, which was closely correlated with the position change of the encapsulated nanoparticle, could be regressed by a power function, the resonance frequency of the carbon-nanotube-resonator could be tuned by controlling the nanoparticle’s position, and the possible frequency-shift-ranges then reached 18–85%. The suggested device could be served as a data-storage-media for electromechanical nonvolatile-memory as well as a frequency-tuner.  相似文献   
85.
The paper is the second part of the review of the results obtained by the special theory of the degenerate problems of optimal control and its applications, including the newest ones. Consideration was given to the methods based on the rearrangement of the degenerate problems in the smaller-order regular derivative problems, the main types of solutions of the derivative problems, and the issues of their realization as the generalized solutions of the original problems. The generalized conditions for their optimality were derived. Examples, both methodological and applied, were presented to demonstrate the efficiency of these methods.  相似文献   
86.
耦合渐变槽线天线及其和差波束的矩量法分析   总被引:2,自引:0,他引:2       下载免费PDF全文
康锴  章文勋 《微波学报》2000,16(1):6-12
本文阐述一种新型渐变槽线天线(TSA)结构,耦合渐变槽线天线CTSA。单片的CTSA除可降低副瓣电平,提高增益,改善E面H面波束的对称外,还可通过与之配合的平面印刷奇偶模双工器馈电,同时实现和差波束。本文应用空间域矩量法(MoM)建立了分析各种TSA结构的数值模型;该方法在没有介质基片的情况下是严重的,本文集中讨论简化MoM中阻抗矩阵积分运算的各种技术,有效地减小了计算量,并获得较高的精度。计算结  相似文献   
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PMMA optical components that are used as one of the most important parts of high precision equipments and machines are increasingly replacing the glass due to the various advantages of PMMA. Especially in Light Guide Panels, the PMMA sheet that is used in Liquid Crystal Displays plays an important role in scattering the incident light and requires very fine machining as the sheet is directly related to the optical characteristics of the panels. The High Speed End milling and High Speed Shaping processes that are widely adopted and applied to the precise machining of Light Incident Plane still have quality problems, such as cracks, breakages, poor waviness, and straightness. This paper presents the tooling device design for machining a Light Incident Plane through vibration-assisted High Speed Shaping for increasing the optical quality by minimizing the above-mentioned problems. The cutting tool and the tool post presented in this paper are designed by the authors to increase the magnitude of the cutting stroke by adopting the resonant frequency without weakening the stiffness and to reduce vibrations during even high speed feeding. The dynamic characteristics of the cutting tool and the tool post are evaluated through simulation and experiment as well. The results reveal very appropriate dynamic characteristics for vibration-assisted High Speed Shaping.  相似文献   
89.
The mathematical model for tension in a moving web by Shin [1] was extended by considering thermal strain due to temperature fluctuations in the drying of a roll-to-roll system. The extended model describes variations in tension and includes terms that represent the change of the Young’s Modulus, the thermal coefficient, and the thermal strain. In this paper, a new control scheme based on the extended model is proposed for mitigation of tension disturbances due to thermal strain in the drying process. Tension feedback control logic generally is not be applied due to the fact that register errors can be induced by speed alterations that help to compensate for tension disturbances. But in our approach, the thermal strain in the web is compensated for by means of velocity adjustments without adding extra register errors in the steady state. A computer simulation followed by an experimental validation was carried out to confirm the performance of the proposed method. The results show that the proposed model is useful for describing tension behavior and suggest that tension control logic improves control precision for the drying module of a roll-to-roll e-printing system.  相似文献   
90.
初夏的安徽省城合肥,气候宜人、绿色醉人.在习习和风的吹拂下,市树广玉兰张开婀娜的花瓣迎接着参加2010中国煤矿瓦斯治理国际研讨会的中外客人.5月29日,来自世界各地约350名中外代表在热情周到的志愿者的带领下步入安徽省合肥市政府小礼堂,参加国际煤矿瓦斯治理领域级别最高的一次会议--2010中国煤矿瓦斯治理国际研讨会.  相似文献   
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