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991.
Wan-Shin Park 《Journal of Constructional Steel Research》2005,61(11):1492-1524
Steel coupling beams in a hybrid coupled shear wall provide a viable alternative for concrete coupling beams coupling individual reinforced concrete wall piers. Due to the lack of information, current design methods for calculating embedment lengths are silent about cases in which hybrid coupled walls have connection details of stud bolts and horizontal ties. In this work, an analytical study was carried out to develop a model for calculating the embedment lengths of embedded steel sections. Five models for calculating embedment lengths in a hybrid coupled wall are developed as variations of the Prestressed Concrete Institute guidelines for steel brackets attached to reinforced concrete columns. In addition, experimental studies on the hybrid coupled shear wall were carried out. The main test variables were the ratios of the coupling beam strength to the connection strength. The test results indicate that it is more advantageous to design the coupling beams as shear yielding members since the shear-critical coupling beam exhibits a more desirable mode of energy dissipation than the flexure-critical coupling beam. 相似文献
992.
993.
四元数和超复数在二维二次非线性相位耦合分析中的应用 总被引:2,自引:0,他引:2
针对二维二次非线性相位耦合分析中的分维配对问题,本文首先对一般二维谐波信号模型进行变换,构造了符合四元数结构的新的信号模型.接着讨论了Hamilton四元数、三维超复数及"新四元数"在估计二维谐波频率中的可能性.最后根据上述模型利用特殊的三阶累积量切片分析了加性高斯有色噪声中二维二次非线性相位耦合及联合Hamilton四元数和超复数在二维二次非线性相位耦合中的应用前景.此方法避免了在复数模型的二维二次非线性相位耦合分析中构造复杂的增广矩阵,并从根本上解决了通过分维求取频率之后,频率配对中所有可能产生的错误频率对,以及有可能产生的两维频率估计精度的不平衡性.仿真实验验证了本文的理论. 相似文献
994.
995.
Analysis for preliminary design of a class of torsionally coupled buildings with horizontal setbacks
Simplified method of analysis of a special class of torsionally coupled buildings with horizontal setbacks is developed that can be executed with a plane frame analysis by means of a personal computer. Since most buildings may not exactly satisfy all the classification criteria, it is shown that an averaging technique may be used in such cases up to a certain limit. Perturbation analysis is carried out in determining such a limit, and numerical examples are presented to validate this. As a whole, the proposed simplified analysis may be used as a convenient and offhand tool at the preliminary stage of design. 相似文献
996.
The oxidative coupling of methane (OCM) has been found to be structure sensitive on La2O3 catalysts exhibiting different crystallite morphologies. Thin plates obtained by thermal decomposition of lanthanum nitrate at 650 °C are more selective on OCM reaction performed at 750 °C than the particles obtained by decomposition of the nitrate at 800 °C. It is assumed that the oxycarbonate observed is formed from the methane deep oxidation on the catalyst surface. This compound appears to act as an intermediate in the production of CO2 and is thus important hi the resulting selectivity. 相似文献
997.
GFRPPS在车辆发动机冷却水泵上的应用研究 总被引:2,自引:0,他引:2
针对车辆发动机冷却水泵的应用环境及对部件的使用要求,计算和性能比较,选择增增增强聚苯硫醚试制了某车发动机冷却水泵的叶轮及进水接盘两个部件。经过台架试验和整机装车试验,证明了用GRPPS制造的发动机冷却泵部件能满足便使用要求。 相似文献
998.
The synthesis of derivatives of Naphtol AS containing polar groups (–COOH, –SO3H) and factors affecting the reaction have been studied. Four derivatives of Naphtol AS containing –COOH or –SO3H groups in the 3- or 4- position of the phenyl ring were synthesized. Derivatives of Naphtol AS as the second coupling component were used in mixed coupling and the effect of its added amount on the colour strength, hue, flowability and dispersing extent (in water) of pigments was studied. 相似文献
999.
Su Hwan Oh Hyunsung Ko Ki Soo Kim Ji‐Myon Lee Chul Wook Lee Oh Kee Kwon Sahnggi Park Moon Ho Park 《ETRI Journal》2005,27(5):551-556
We have demonstrated a high‐power widely tunable sampled grating distributed Bragg reflector (SGDBR) laser integrated monolithically with a semiconductor optical amplifier (SOA) having a lateral tapered waveguide, which is the first to emit a fiber‐coupled output power of more than 10 dBm using a planar buried heterostructure (PBH). The output facet reflectivity of the integrated SOA using a lateral tapered waveguide and two‐layer AR coating of TiO2 and SiO2 was lower than 3 × 10?4 over a wide bandwidth of 85 nm. The spectra of 40 channels spaced by 50 GHz within the tuning range of 33 nm were obtained by a precise control of SG and phase control currents. A side‐mode suppression ratio of more than 35 dB was obtained in the whole tuning range. Fiber‐coupled output power of more than 11 dBm and an output power variation of less than 1 dB were obtained for the whole tuning range. 相似文献
1000.
研制了对混凝土坝及基岩进行水弹性模拟的新配方和材料,并用此材料成功地对黄河拉西瓦高拱坝坝身泄漏的流激振动进行水弹性模拟试验。在比尺为1:150的拱坝-地基-库水耦合系统的水弹性整体模型上,进行了实验模态分析,给出系统的空、满库的模态特性并与理论模态相比较;测定了拱坝坝身泄洪水舌跌落水垫塘消能时,紊流流振动的动力响应,定量地给出响应的强度和频谱;论证了高拱坝坝身泄洪的安全性。 相似文献