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821.
该文介绍了节电产品在船闸用电中的运用,对解决电力供需矛盾,减少电力浪费,提高设备使用效率,建设节约型单位具有一定的借鉴意义。 相似文献
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Although the nonlinear effects of the ship motions, wave-induced loads and structural responses of conventional vessels have been investigated experimentally and numerically in recent years, similar studies on the wave-piercing tumblehome (WPTH) vessels are rare, in spite of the urgent necessary due to their extensive applications. This paper experimentally investigated the nonlinear effects of the vertical motions and vertical bending moment (VBM) for a WPTH vessel based on a hydro-elastic segmented model test. The model test was carried out in head regular waves for three amplitudes, in the towing tank at Harbin Engineering University. Based on the band-pass filter technique, four kinds of decomposed harmonics are defined by mean offset, linear wave-frequency response, nonlinear wave-frequency response and nonlinear high-frequency vibration. Meanwhile, based on mean offset, three kinds of combined responses are defined by considering linear wave-frequency response, nonlinear wave-frequency response and nonlinear high-frequency vibrations step by step. The transfer functions of vertical motions and VBM are presented as function of the incident wave frequency, and the measured data and VBM were compared with numerical calculations for validation. With the method proposed above, the results of VBM are analyzed by focusing on the influences of decomposed harmonics on the amplitudes and asymmetry of combined responses. Strong nonlinear effects are observed in the VBM. The nonlinearity of VBM can be identified by the significant amplitudes of decomposed harmonics, variation of amplitude with the wave amplitude and remarkable asymmetry about the zero axis. The hogging VBM of WPTH vessel can be even larger than the sagging VBM, which is in contrast to the general experiences from conventional vessels. Combined the calculated relative motion with the decomposed and combined histories of VBM, the occurrence of the transient impact and its characteristics are discussed, and these are then used to analyze the unconventional asymmetry of VBM. Furthermore, the influences of the bow shape over the vertical motions and VBM are discussed. At the end of the paper, the uncertainties in the test are provided. 相似文献
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以一圆弧形太阳能板双体无人船为例,研究该类双体船在规则波中随浪状态下的破舱稳性。建立带水密箱式连接桥结构的双体无人船模型,对不同影响因素变化下双体无人船的破舱稳性进行分析,得出破舱稳性与影响因素之间的关系。研究结果表明:波陡增加,极限静倾角增大,无人船稳性恶化;波峰位于船舯附近时,无人船稳性较差;片体间距越大,破舱稳性越好,极限静倾角越小;艏部舱室破损后,无人船稳性恶化较严重。 相似文献
824.
SOTDMA在船载AIS中的应用 总被引:3,自引:0,他引:3
分析了自组织时分多址接续(SOTDMA)技术在船载自动识别系统(AIS)中的应用。通过硬件设计和软件编程,实现了SOTDMA的时隙划分、时隙同步和访问。 相似文献
825.
[目的]旨在研究跨域无人平台从水面垂直起飞过程中平台的运动及动力学特性.[方法]采用黏流CFD方法结合重叠网格技术和多自由度DFBI(dynamic fluid body interaction)运动模型,针对跨域无人平台在水面垂直起飞至空中的跨域过程的动态特性,开展数值模拟研究.[结果]模拟结果显示:在垂直起飞过程中... 相似文献
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