Results 81 to 90 of about 5,293 (164)
Dianci bileiqi, 2015 根据江西省雷电定位系统2012年至2014年的LLS监测数据,采用经验正交分解方法,分析研究了江西省雷电时空分布特点,得出主要的空间特征向量及其对应的时间系数。结果表明,近3a夏半年雷电活动的空间分布特征以经向型为主,南部及山区雷电活动频繁。对空间特征向量所对应的时间系数的分析发现,江西近3a夏半年雷电活动总体呈增长趋势,时间系数间存在较强的相似特征,表明区域雷电活动具有一定的时空延续性。
童军心 +5 more
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Study on the May 28 Birch high-altitude and long-runout ice-rock avalanche in the Swiss Alps [PDF]
On May 28, 2025, a high-altitude and long-runout ice-rock avalanche disaster occurred at the Birch Glacier in the Alps of the Valais region in southern Switzerland.
Chaoping YANG +4 more
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Gaoya dianqi, 2020 变压器振动与其运行状态密切相关,为了实现基于振动的变压器运行状态评价,对现场运行的62台110 kV主变进行了振动测试,以变压器振动加速度幅值、基频幅值、基频比重、主频幅值、主频比重以及频谱复杂度为特征量,并对特征量的数值分布进行了统计分析,确定了现场正常运行变压器的特征量分布范围,分析了运行年限对变压器振动特征的影响。结果表明,大多数变压器振动加速度幅值、基频幅值、基频比重、主频幅值、主频比重以及频谱复杂度分别位于5.0、1.0、0.3、2.0、0.9、3.0 m/s2范围内 ...
吴晓文 +5 more
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Optical-electrical-acoustic wave multiparameter response characteristics of typical rocks in coal-bearing strata throughout the loading process [PDF]
Objective The deformations and rupture of rocks under loading will cause potential changes in parameters. Dynamic parameter capture assists in characterizing the generation, propagation, and closure processes of fractures, serving as a significant method
Chang LIU, Pingsong ZHANG
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Mine microseismic and electrical coupling monitoring technology [PDF]
With the increase of the depth, mining intensity and area of coal resource, the mining disturbances in the mining face can easily induce mine water inrush accidents, seriously threatening the safe mining of coal resources in China.
Cai YANG +4 more
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Gaoya dianqi, 2016 为了解复合绝缘子在污闪过程中泄漏电流变化特征,在人工雾室中开展了复合绝缘子污闪试验研究,测量和分析了试验过程中泄漏电流波形的时域和频域特征。分析结果表明,泄漏电流幅值、基波、三次谐波和五次谐波相互间具有较强的相关性,提出以泄漏电流最大值（Im）、总谐波失真率（THD）、泄漏电流基波相位差（θ）表征泄漏电流频谱特征;临闪时,泄漏电流具有幅值高、谐波含量少、泄漏电流基波与电压间相位差小的特点。研究结果为建立基于泄漏电流特征量的污闪预警系统提供了依据。
方春华 +5 more
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Diagnosis of Sleep Apnea Hypopnea Syndrome Using Fusion of Micro-motion Signals from Millimeter-wave Radar and Pulse Wave Data [PDF]
Sleep Apnea Hypopnea Syndrome (SAHS) is a common chronic sleep-related breathing disorder that affects individuals’ sleep quality and physical health. This article presents a sleep apnea and hypopnea detection framework based on multisource signal fusion.
Chenyang LI +4 more
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Experimental study on influence of fault dip angle on acoustic emission sinal propagation [PDF]
Natural rock mass is not a uniform continuum due to discontinuous interfaces such as faults and bedding planes between rock layers, and the propagation law of acoustic emission signals will inevitably change when they pass through faults and bedding ...
Bao LI, Baoxin JIA, Hao CHEN, Linli ZHOU
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Survey of deep fake audio generation and detection techniques [PDF]
With the rapid development of deep learning technology, fake audio generation technology, especially deep fake audio generation, has become a major challenge in the field of digital media security.
QU Xiaoyang +4 more
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Gaoya dianqi, 2008 为了更好地分析电晕放电辐射信号的特征,笔者利用尖端电晕放电模拟测试系统采集了电晕放电辐射信号数据,研究分析了信号在时域和频域的一些特性。分析结果表明,电晕放电辐射信号首脉冲的方向随放电电压的极性不同而相反,在不同极性放电电压下,放电辐射信号的时域特征差别比较明显,但频谱分布基本一致,放电能量主要集中在50～100MHz之间,频率范围主要在150MHz以下。
刘卫东 +3 more
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