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51.
Maíra Martins da Silva Olivier Brüls Wim Desmet Hendrik Van Brussel 《Mechatronics》2009,19(6):1016-1025
This paper considers the optimal design of mechatronic systems with configuration-dependent dynamics. An optimal mechatronic design requires that, among the structural and control parameters, an optimal choice has to be made with respect to design specifications in the different domains. Two main challenges are treated in this paper: the non-convex nature of the optimization problem and the difficulty in modeling serial machines with flexible components and their embedded controllers. The optimization problem is treated using the direct design strategy which considers simultaneously structural and control parameters as variables and adopts non-convex optimization algorithms. Linear time-invariant and gain-scheduling PID controllers are addressed. This methodology is exploited for the multi-objective optimization of a pick-and-place assembly robot with a gripper carried by a variable-length flexible beam. The resulting design tradeoffs between system accuracy and control efforts demonstrate the advantage of an integrated design approach for mechatronic systems with configuration-dependent dynamics. 相似文献
52.
本文介绍了直视芯式单模光纤熔接机采用柔性铰链式微动机构的原理及构成,其调整精度可达到±0.1μm,使单模光纤熔接机的连接损耗大大降低。另外,还对其性能及指标与日本产品进行了比较。 相似文献
53.
Here, we report on the performance and the characterization of all solution-processable top-contact organic thin-film transistors (OTFTs) consisting of a natural-resourced triacetate cellulose gate dielectric and a representative hole-transport poly[2,5-bis(3-dodecylthiophen-2-yl)thieno[3,2-b]thiophene] (pBTTT) semiconductor layer on rigid or flexible substrates. The bio-based triacetate cellulose layer has an important role in the OTFT fabrication because it provides the pBTTT semiconducting polymer with highly suitable gate dielectric properties including a low surface roughness, hydrophobic surface, appropriate dielectric constant, and low leakage current. The triacetate cellulose gate dielectric-based pBTTT OTFTs exhibit an average filed-effect mobility of 0.031 cm2/Vs similar to that obtained from a SiO2 gate dielectric-based OTFT device in ambient conditions. Even after a bending stimulation of 100 times and in an outward bending state, the flexible triacetate cellulose gate pBTTT OTFT device still showed excellent electrical device performance without any hysteresis. 相似文献
54.
We report the enhancement of the thermoelectric power factors of single-walled carbon-nanotube (SWCNT) films caused by the addition of polystyrene to the films as a binder. The Seebeck coefficient of the SWCNT films was increased by addition of polystyrene. On the other hand, the electrical conductivity gradually decreased with increasing amount of polystyrene. The power factor was maximum for a polystyrene concentration of 20 wt%; it was approximately 1.7 times higher than that of a pure SWCNT film. These results indicate that polystyrene is a superior binder polymer for synthesizing CNT/polymer thermoelectric composites. 相似文献
55.
C. R. Helms J. L. Meléndez H. G. Robinson S. Holander J. Hasan S. Halepete 《Journal of Electronic Materials》1995,24(9):1137-1142
The strategy and status of a process simulator for the flexible manufacture of HgCdTe infrared focal plane arrays is described.
It has capabilities to simulate Hg vacancy and interstitial effects and cation impurity diffusion, for various boundary conditions
in one dimension. Numerical complexity of these problems stems from the necessity of solving diffusion equations for each
defect that are coupled to each other via nonlinear interaction terms. The simulator has already led to the prediction of
heretofore unexplained experimental data. Current extensions of the one-dimensional simulator planned over the next few years
include the addition of Te antisites, antisite-Hg vacancy pairs, and In-Hg vacancy pairs, ion implantation, and various energetic
processes (such as ion milling). The sequential effect of various processes will be possible with the input to the simulator
looking much like a process run sheet. 相似文献
56.
57.
Jaewon Jang Kyoungah Cho Junggwon Yun Sangsig Kim 《Microelectronic Engineering》2009,86(10):2030-2033
We demonstrate bottom-gate thin-film transistors (TFTs) based on solution-processed HgSe nanocrystals (NCs) on plastic substrates. Solid films made of spin-coated HgSe NCs were heated at a temperature of 150 °C for 15 min to maximize the magnitude of their current, and these films were utilized as the channel layers of TFTs. A representative TFT with a bottom-gate Al2O3 layer operated as a depletion-mode one with an n-channel, exhibiting a field effect mobility of 3.9 cm2/Vs and an on/off current ratio of about 102. In addition, the electrical characteristics of the TFT on bent substrates are briefly described. 相似文献
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