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Hilbert变换 1

动量守恒 1

子带瞬时能量谱 1

弹丸速度 1

本征模式函数 1

槽况敏感频段 1

爆炸成型弹丸 1

瞬时参数 1

瞬时爆轰产物飞散 1

端点失真 1

铝液异常波动 1

铝电解 1

频域分段 1

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On the location of the secondary instantaneous poles in two-degree-of-freedom spherical mechanisms

Soheil ZARKANDI

《机械工程前沿（英文）》 2014年第9卷第1期页码 34-40 doi: 10.1007/s11465-014-0290-1

摘要：

As the instant centers in planar mechanisms, the instantaneous poles (or instant poles, in brief) can be used for kinematic analysis in spherical mechanisms. One of the mandatory steps in this analysis is the determination of the location of these poles. This paper presents a theorem showing analytically that the locus of an unknown secondary instant pole in two-degree-of-freedom (2-DOF) spherical mechanisms is a great circle (GC). The exact location of the pole on its GC is obtained based on the configuration of the mechanism and velocity ratio of the two inputs. Moreover, using the results of the theorem, a geometrical technique is presented to determine the GC of the pole.

关键词： spherical mechanisms instantaneous poles great circle angular velocity

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A survey of instantaneous poles for a class of two-degree-of-freedom spherical mechanisms

Soheil ZARKANDI

《机械工程前沿（英文）》 2014年第9卷第4期页码 344-353 doi: 10.1007/s11465-014-0320-z

摘要：

This paper is a detailed exploration of instantaneous poles for a class of two-degree-of-freedom (two-DOF) spherical mechanisms (SMs) with seven links or bars. For two-DOF SMs, the secondary instantaneous poles (the ones which cannot be found by direct inspection) must lie on the specified great circles. For many of these mechanisms, however, some of these great circles cannot be obtained by a direct application of Aronhold-Kennedy theorem. This paper presents geometrical and analytical techniques to locate these unknown great circles for three topologies of seven-bar two-DOF SMs.

关键词： spherical mechanisms instantaneous poles Aronhold-Kennedy theorem great circles pencil of meridian

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Instantaneous deflection of light-weight concrete slabs

Behnam VAKHSHOURI, Shami NEJADI

《结构与土木工程前沿（英文）》 2017年第11卷第4期页码 412-423 doi: 10.1007/s11709-017-0416-8

摘要： Construction loading before the age of 28 d can have the most significant effects on the slabs, especially for multi-story structures. The changing properties of the young concrete complicate the prediction of serviceability design requirements also. An experimental investigation is performed on four simply supported Light-Weight Concrete (LWC) one-way slabs subjected to immediate loading at 14 d. Effects of aggregate type, loading levels and cracking moment together with the influences of ultimate moment capacity and service moment on the instantaneous deflection of slabs are studied. Comparison of the obtained results with predictions of existing models in the literature shows considerable differences between the recorded and estimated instantaneous deflection of LWC slabs. Based on sensitivity analysis of the effective parameters, a new equation is proposed and verified to predict the instantaneous deflection of LWC slabs subjected to loading at the age of 14 d.

关键词： instantaneous deflection light-weight concrete expanded polystyrene effective moment of inertia cracking moment moment capacity service moment

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爆炸成型弹丸速度计算方法研究

赵慧英,沈兆武

《中国工程科学》 2007年第9卷第8期页码 62-65

摘要：

从炸药装药的瞬时爆轰产物飞散理论出发，根据动量守恒原理得出药型罩装药形成爆炸成型弹丸的速度计算模型，并根据装药高度与直径之比对弹丸速度的影响修正了计算模型。应用该计算模型计算了大锥角药形罩和球缺药型罩装药形成的爆炸成型弹丸速度，计算结果与实验和数值模拟得到的结果吻合较好，此速度计算模型适合于工程应用。

关键词：爆炸成型弹丸瞬时爆轰产物飞散动量守恒弹丸速度

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基于子带瞬时能量谱的铝电解槽电压槽况敏感频域分段方法 Article

曾朝晖, 桂卫华, 陈晓方, 谢永芳, 张红亮, 孙玉波

《工程（英文）》 2021年第7卷第9期页码 1282-1292 doi: 10.1016/j.eng.2020.11.012

摘要：在对槽电压定性分析的基础上，本文提出子带瞬时能量谱（sub-band Instantaneous energy spectrum, SIEP），并用其对多种槽况下槽电压的频域特性进行定量表示，最终给出了槽电压槽况敏感频域分段方法

关键词：子带瞬时能量谱槽况敏感频段频域分段铝液异常波动铝电解

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Rapid transaction to load variations of active filter supplied by PV system

M. BENADJA,S. SAAD,A. BELHAMRA

《能源前沿（英文）》 2014年第8卷第3期页码 335-344 doi: 10.1007/s11708-014-0325-7

摘要： This paper deals with the analysis and control of a photovoltaic (PV) system connected to the main supply through a Boost converter and shunt active filter supplied by a PV system providing continuous supply of nonlinear load in variation. A robust control of a PV system connected to the grid while feeding a variable nonlinear load is developed and highlighted. This development is based on the control of the Boost converter to extract the maximum power from the PV system using the Perturb and Observe (P and O) algorithm in the presence of temperature and illumination. The proposed modeling and control strategy provide power to the variable nonlinear load and facilitates the transfer of power from solar panel to the grid while improving the quality of energy (harmonic currents compensation, power factor compensation and dc bus voltage regulation). Validation of the developed model and control strategy is conducted using power system simulator Sim-Power System Blockset Matlab/Simulink. To demonstrate the effectiveness of the shunt active filter to load changes, the method of instantaneous power ( theory) is used to identify harmonic currents. The obtained results show an accurate extraction of harmonic currents and perfect compensation of both reactive power and harmonic currents with a lower THD and in accordance with the IEEE-519 standard.

关键词： solar panels maximum power point tracking (MPPT) DC/DC converter (Boost) shunt active filter instantaneous power control power quality harmonics imbalances reactive energy