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311.
Ching-Chien Cheng Kong-Xin Cheng Huang-Kuang Kung Chin-Yu Wang Yng-Huey Jeng Sheng-Lung Tu Chun-Chieh Huang 《Optical and Quantum Electronics》2017,49(8):283
An H-shape dual-mode closed resonator with self-coupled segments is reported. The self-coupling between ring segments renders an equivalent mode perturbation effect as the normal ways of adding stub, cutting notch, or varying line impedance to the ring resonator. The mode perturbation and transmission-zero generation from the self-coupling effect and step-impedance were analyzed using the even–odd mode theory. By regulating the impedance ratio and coupling coefficients of self-coupled sections, the self-coupled ring resonator can produce either the capacitive or inductive perturbation. The input and output positions affect the number and locations of transmission zero. The positions of input and output ports are properly selected. In the capacitive perturbation case, when the two transmission zeros are located on both sides of the passband, and bring about a pseudo-elliptic bandpass response. The analysis of finding optimized taping positions of input and output ports is proposed. Comparing to the regular uniform ring resonator, the H-shaped self-coupled ring resonator has shorter ring length, is easily to be folded and does not destroy the dual-mode characteristics. The feature of compact size is favorable in the design of a bandpass filter. A 2.45-GHz bandpass filter based on the H-shaped self-coupled ring resonator was performed to verify the proposed theory. A schematic bandpass filter was implemented with a compact size which is only 20% of the conventional dual-mode bandpass filter. 相似文献
312.
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314.
There is considerable current interest in the development of constitutive equations for pressure-dependent plastic materials. In particular, in contrast to classical plasticity there is no commonly accepted relation to connect stress and strain or strain rate for such materials. Analytic and semi-analytic solutions are convenient to compare qualitative features of boundary value problems solved for different models. Such comparative studies can be useful to choose this or that model for specific applications. Analytic and semi-analytic solutions are also necessary to verify numerical codes. In the present paper, a new semi-analytic solution for a thin hollow disc subject to thermal loading is developed. A numerical method is only necessary to solve transcendental equations. The constitutive equations for connecting the plastic portion of the strain rate tensor and the stress tensor consist of the Drucker-Prager yield criterion and its associated flow rule. Therefore, the main distinguished feature of the solution is that the material is plastically compressible. 相似文献
315.
在LCD-TV中通过采用扫描背光源和在数据帧中插入黑色帧的方法,可以显著改善对比度和运动模糊现象。 相似文献
316.
Jeng‐Yueh Shieh Shih‐Peng Yang Mei‐Feng Wu Chun‐Shan Wang 《Journal of polymer science. Part A, Polymer chemistry》2004,42(11):2589-2600
For the purpose of increasing the mobility of residual bisphenol A dicyanate ester (BADCY) during the final stage of curing and achieving a complete reaction of cyanate groups, a small quantity of monofunctional phenol was added to BADCY to form an imidocarbonate, or a small quantity of monofunctional cyanate esters was added to form cyanate ester copolymers. The proposed structures were confirmed with Fourier transform infrared, elemental analysis, mass spectrometry, and NMR spectroscopy. The thermal properties of the cured cyanate esters were measured with dynamic mechanical analysis, thermogravimetric analysis, and dielectric analysis. These data were compared with those for the cured BADCY resin. The cured modified cyanate esters exhibited a lower dielectric constant, a lower dissipation factor, and lower moisture absorption than the cured BADCY system. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2589–2600, 2004 相似文献
317.
Jeng Yune Park 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2000,46(6):2228-2235
We determine the weight hierarchies of the product of an n-tuple space and an arbitrary code, the product of an m-dimensional even-weight code and the [24,12,8] extended Golay code, and the product of an m-dimensional even-weight code and the [8,4,4] extended Hamming code. The conjecture dr=d*r is proven for all three cases 相似文献
318.
Differing from FDMA, TDMA, and CDMA, space division multiple access (SDMA) uses space resources to improve communication system performance. Utilizing the smart antenna system is an approach to realize the SDMA technique. Smart antenna systems using the beamforming technique can reduce the co‐channel interference and multipath fading to increase the channel capacity and communication quality. In this study the smart antenna system and rake receiver are integrated. The performance of spatial–temporal structure applied to the W‐CDMA system is evaluated. From the cumulative distribution function simulation results, W‐CDMA system with spatial–temporal algorithm can exactly provide SINR gain to improve the system performance and capacity. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
319.
Ying‐Ling Liu Shr‐Hau Tsai Chuan‐Shao Wu Ru‐Jong Jeng 《Journal of polymer science. Part A, Polymer chemistry》2004,42(23):5921-5928
Hyperbranched polyaspartimides were successfully prepared from bismaleimides (A2) and triamines (B3) through the Michael addition reaction. Two bismaleimides of 4,4′‐bismaleimidodiphenylmethane (BMDM) and bis(3‐ethyl‐5‐methyl‐4‐ maleimidophenyl)methane (BEMM) and two triamines of tris(3‐aminophenyl)phosphine oxide (TAPPO) and tris(4‐aminophenyl)amine (TAPA) were employed in the preparation of these hyperbranched polyaspartimides. The chemical structures of the polymers were characterized with Fourier transform infrared (FTIR), 1H and 31P NMR, and elemental analysis. Degrees of branching ranging from 0.51 to 0.69 were found with the polyaspartimides, ensuring their hyperbranched structure. The polymers also showed good solubility in common solvents, high glass‐transition temperatures of 256 °C, and excellent thermal stability above 370 °C. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5921–5928, 2004 相似文献
320.
Real-time traffic parameter extraction using entropy 总被引:3,自引:0,他引:3
Hsu W.-L. Liao H.-Y.M. Jeng B.-S. Fan K.-C. 《Vision, Image and Signal Processing, IEE Proceedings -》2004,151(3):194-202
A vision-based traffic monitoring system that can perform real-time traffic parameter extraction is proposed. The entropy measurement, which is commonly adopted as an important feature to describe the degree of disorder in thermodynamics, is used as an underlying feature in this work. Based on an entropy measurement, a number of important traffic parameters, such as traffic flow, space mean speed and traffic queue, can be determined in real time. The experimental results clearly show that the proposed system is highly effective. 相似文献