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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
Luke Yu 《Industry Applications, IEEE Transactions on》1995,31(2):379-383
The lattice diagram has been widely recognized and adopted to analyze the voltage surges produced at a particular location in an electrical system. These transient surges are caused by traveling waves induced by lightning strokes or switching operations. A lattice diagram can be used effectively, but the required computations are tedious. A simplified approach based on mathematical derivation is presented. The method will permit a quick evaluation of both initial and crest surge magnitudes as well as a wave shape that are all based on a given incoming surge and the surge impedances of the electrical elements involved. Sample calculations from the lattice diagram and the proposed quick evaluation are compared 相似文献
992.
本文从理论上分析了矩形波和正弦脉波气流对流化床操作性能的影响,发现矩形波在一定条件下优于正弦波的规律,并用实际进行了验证。 相似文献
993.
994.
995.
Dongho Chae O. Yu. Imanuvilov Sang Moon Kim 《Journal of Dynamical and Control Systems》1996,2(4):449-483
This paper studies the problem of exact boundary controllability of second-order semilinear parabolic equations when the control is under Neumann's boundary conditions. For a nonlinear term with a sublinear growth we prove the global null-controllability and for the superlinear growth case we prove the local exact controllability of the equations. 相似文献
996.
阐述了新型线圈式磁弹性扭矩传感器的原理,推导出其输出表达式,进而说明了线圈式磁弹性扭矩传感器具有输出平稳、响应快的特点。 相似文献
997.
Time-varying adaptive filters for evoked potential estimation 总被引:4,自引:0,他引:4
Xiao-Hu Yu Zhen-Ya He Yi-Sheng Zhang 《IEEE transactions on bio-medical engineering》1994,41(11):1062-1071
Adaptive implementation of an optimal time-varying filter (TVF) for evoked potential (EP) estimation is addressed here. A data-adaptive scheme is used, which converges asymptotically to the optimal TVF solution. Two basic adaptive TVF's (ATVF's) are first introduced, namely least mean square (LMS) ATVF and recursive least-squares (RLS) ATVF. The latter converges much faster than the former. Since the basic ATVF's usually require a relatively large set of response trials to get a meaningful solution, a reduced-order ATVF is further presented and the corresponding LMS and RLS (including a fast RLS) adaptive algorithms are developed. To save memory, a truncated Fourier expansion is suggested to express approximately the time-sequenced weight-vectors of the ATVF's, resulting in a simplified reduced-order ATVF. Finally, extensive simulations are provided to confirm the superior performance of the ATVF's. The present ATVF's can be used as prefilters for latency-corrected average (LCA) processing to obtain more informative estimates of EP signals 相似文献
998.
分析了WTG420铁路罐车用钢的组织结构和力学性能。提出了冶炼与轧制的技术关键,其一,添加稀土元素改善钢中夹杂物;其二,采用控轧控冷使铁素体晶粒细化。 相似文献
999.
利用氧化铁皮烧结矿做炼钢氧化剂的探讨 总被引:3,自引:0,他引:3
用氧化铁皮研制烧结放代替铁矿石做炼钢氧化剂经试验表明,其理化性能均优于铁矿石,可替代铁矿石作为炼钢的氧化剂。氧化铁皮的开发利用,综合效益显著。 相似文献
1000.
Yung Chien Hsu Hung-Ch'i Chang 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1995,64(2):137-148
The behavior of inducted gas from liquid surface and the; power requirements in an agitated tank using a mechanical agitator are studied in order to increase the amount of gas self-induction and the gas retention time for gas absorption. A 45° six-blade downward impeller turbine was utilized in this study. Air and water, air and 40 wt% 60 wt%, and 80 wt% of glycerin water, and air and 106 cP silicon oil were employed as gas and liquid phases. Variables which were studied included geometrical factors (immersed depth of impeller, baffle with and diameter of impeller) and the physical properties of the liquid (viscosity, density, and surface tension). The correlations for the onset speed of impeller and power consumption after gas induction in the agitated tank are established from our experimental results. The amount of gas self-induction from the liquid surface in the agitated tank increases with increasing impeller diameter and speed and decreases with increasing baffle width, depth of impeller and viscosity of liquid. 相似文献