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Source time functions of the Gonghe,China earthquake retrieved from long-period digital waveform data using empirical Green's function technique 被引量:7
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作者 许力生 陈运泰 《Acta Seismologica Sinica(English Edition)》 CSCD 1996年第2期209-222,共14页
An earthquake of Ms= 6, 9 occurred at the Gonghe, Qinghai Province, China on April 26, 1990. Three larger aftershocks took place at the same region, Ms= 5. 0 on May 7, 1990, Ms= 6. 0 on Jan. 3, 1994 and Ms= 5. 7on Feb... An earthquake of Ms= 6, 9 occurred at the Gonghe, Qinghai Province, China on April 26, 1990. Three larger aftershocks took place at the same region, Ms= 5. 0 on May 7, 1990, Ms= 6. 0 on Jan. 3, 1994 and Ms= 5. 7on Feb. 16, 1994. The long-period recordings of the main shock from China Digital Seismograph Network (CDSN) are deconvolved for the source time functions by the correspondent0 recordings of the three aftershocks asempirical Green's functions (EGFs). No matter which aftershock is taken as EGF, the relative source time functions (RSTFs) Obtained are nearly identical. The RSTFs suggest the Ms= 6. 9 event consists of at least two subevents with approximately equal size whose occurrence times are about 30 s apart, the first one has a duration of 12 s and a rise time of about 5 s, and the second one has a duration of 17 s and a rise time of about & s. COmParing the RSTFs obtained from P- and SH-phases respectively, we notice that those from SH-phases are a slightly more complex than those from p-phases, implying other finer subevents exist during the process of the main shock. It is interesting that the results from the EGF deconvolution of long-Period way form data are in good agreement with the results from the moment tensor inversion and from the EGF deconvolution of broadband waveform data. Additionally, the two larger aftershocks are deconvolved for their RSTFs. The deconvolution results show that the processes of the Ms= 6. 0 event on Jan. 3, 1994 and the Ms= 5. 7 event on Feb. 16,1994 are quite simple, both RSTFs are single impulses.The RSTFs of the Ms= 6. 9 main shock obtained from different stations are noticed to be azimuthally dependent, whose shapes are a slightly different with different stations. However, the RSTFs of the two smaller aftershocks are not azimuthally dependent. The integrations of RSTFs over the processes are quite close to each other, i. e., the scalar seismic moments estimated from different stations are in good agreement. Finally the scalar seismic moments of the three aftershocks are compared. The relative scalar seismic moment Of the three aftershocks deduced from the relative scalar seismic moments of the Ms=6. 9 main shock are very close to those inverted directly from the EGF deconvolution. The relative scalar seismic moment of the Ms =6. 9 main shock calculated using the three aftershocks as EGF are 22 (the Ms= 6. 0 aftershock being EGF), 26 (the Ms= 5. 7 aftershock being EGF) and 66 (the Ms= 5. 5 aftershock being EGF), respectively. Deducingfrom those results, the relative scalar sesimic moments of the Ms= 6. 0 to the Ms= 5. 7 events, the Ms= 6. 0 tothe Ms= 5. 5 events and the Ms= 5. 7 to the Ms= 5. 5 events are 1. 18, 3. 00 and 2. 54, respectively. The correspondent relative scalar seismic moments calculated directly from the waveform recordings are 1. 15, 3. 43, and 3. 05. 展开更多
关键词 Gonghe earthquake empirical Green' function waveform data source time function.
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Source time functions of the 1999, Jiji (Chi-Chi) earthquake from GDSN long period waveform data using aftershocks as empirical Green's functions 被引量:1
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作者 许力生 G.Patau 陈运泰 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2002年第2期121-133,共13页
A large earthquake (Mw=7.6) occurred in Jiji (Chi-Chi), Taiwan, China on September 20, 1999, and was followed by many moderate-size shocks in the following days. Two of the largest aftershocks with the magnitudes of M... A large earthquake (Mw=7.6) occurred in Jiji (Chi-Chi), Taiwan, China on September 20, 1999, and was followed by many moderate-size shocks in the following days. Two of the largest aftershocks with the magnitudes of Mw=6.1 and Mw=6.2, respectively, were used as empirical Green's functions (EGFs) to obtain the source time functions (STFs) of the main shock from long-period waveform data of the Global Digital Seismograph Network (GDSN) including IRIS, GEOSCOPE and CDSN. For the Mw=6.1 aftershock of September 22, there were 97 pairs of phases clear enough from 78 recordings of 26 stations; for the Mw=6.2 aftershock of September 25, there were 81 pairs of phases clear enough from 72 recordings of 24 stations. For each station, 2 types of STFs were retrieved, which are called P-STF and S-STF due to being from P and S phases, respectively. Totally, 178 STF individuals were obtained for source-process analysis of the main shock. It was noticed that, in general, STFs from most of the stations had similarities except that those in special azimuths looked different or odd due to the mechanism difference between the main shock and the aftershocks; and in detail, the shapes of the STFs varied with azimuth. Both of them reflected the stability and reliability of the retrieved STFs. The comprehensive analysis of those STFs suggested that this event consisted of two sub-events, the total duration time was about 26 s, and on the average, the second event was about 7 s later than the first one, and the moment-rate amplitude of the first event was about 15% larger than that of the second one. 展开更多
关键词 Jiji (Chi-chi) earthquake long-period waveform source time function
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A Modified Discrete-Time Jacobi Waveform Relaxation Iteration
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作者 Yong Liu Shulin Wu 《Applied Mathematics》 2011年第4期496-503,共8页
In this paper, we investigate an accelerated version of the discrete-time Jacobi waveform relaxation iteration method. Based on the well known Chebyshev polynomial theory, we show that significant speed up can be achi... In this paper, we investigate an accelerated version of the discrete-time Jacobi waveform relaxation iteration method. Based on the well known Chebyshev polynomial theory, we show that significant speed up can be achieved by taking linear combinations of earlier iterates. The convergence and convergence speed of the new iterative method are presented and it is shown that the convergence speed of the new iterative method is sharper than that of the Jacobi method but blunter than that of the optimal SOR method. Moreover, at every iteration the new iterative method needs almost equal computation work and memory storage with the Jacobi method, and more important it can completely exploit the particular advantages of the Jacobi method in the sense of parallelism. We validate our theoretical conclusions with numerical experiments. 展开更多
关键词 DISCRETE-time waveform Relaxation Convergence Parallel Computation CHEBYSHEV Polynomial JACOBI ITERATION Optimal SOR
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Photonic generation of arbitrary waveforms based on incoherent wavelength-to-time mapping
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作者 董建绩 罗博文 +1 位作者 于源 张新亮 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第6期538-542,共5页
We demonstrate experimentally a radio frequency arbitrary waveform generator using the incoherent wavelength-to-time mapping technique. The system is implemented by amplitude modulation of a broadband optical resource... We demonstrate experimentally a radio frequency arbitrary waveform generator using the incoherent wavelength-to-time mapping technique. The system is implemented by amplitude modulation of a broadband optical resource whose spectrum is reshaped by a programmable optical pulse shaper and transmitted over a single mode fiber link. The shape of the generated waveform is controlled by the optical pulse shaper, and the fiber link introduces a certain group velocity delay to implement wavelength-to-time mapping. Assisted by the flexible optical pulse shaper, we obtain different shapes of optical waveforms, such as rectangle, triangle, and sawtooth waveforms. Furthermore, we also demonstrate ultra-wideband generation, such as Gaussian monocycle, doublet, and triplet waveforms, using the incoherent technique. 展开更多
关键词 arbitrary waveform generation ULTRA-WIDEBAND wavelength-to-time mapping incoherenttechnique arbitrary waveform generation ULTRA-WIDEBAND wavelength-to-time mapping incoherent technique
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Photonics Improvement of the Time-Bandwidth Product for a Linearly Chirped Waveform
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作者 Xuan Li Shanghong Zhao +1 位作者 Guodong Wang He Li 《Journal of Applied Mathematics and Physics》 2020年第12期2955-2963,共9页
<div style="text-align:justify;"> A photonics approach to generate a linearly chirped waveform with increased TBWP is proposed and investigated. The time bandwidth product (TBWP) of the linearly chirpe... <div style="text-align:justify;"> A photonics approach to generate a linearly chirped waveform with increased TBWP is proposed and investigated. The time bandwidth product (TBWP) of the linearly chirped waveform is improved based on optical microwave frequency multiplying combined with temporal synthesis. An integrated dual-polarization modulator and an optical filter are utilized to perform frequency doubling operation by generating an orthogonally polarized optical signal, which consists of an optical carrier in one polarization direction and a second-order chirped optical sideband in another. Then the orthogonally polarized optical signal puts into a polarization modulator (PolM) to perform phase coding process. By driving a Pseudorandom (PN) sequence to the PolM, the time duration of the generated bandwidth doubled linearly chirped waveform can be synthesized to arbitrary length. The approach is verified by simulation. A linearly chirped waveform with central frequency of 8.25 GHz, bandwidth of 500 MHz, time duration of 6.4 ns is used to generate a synthesized waveform with central frequency of 16.5 GHz, bandwidth of 1 GHz, time duration of 819.2 ns. The TBWP of the linearly chirped signal is improved from 3.2 to 819.2. The proposed method features arbitrary large TBWP, and it can be used in a radar system to improve its resolution. </div> 展开更多
关键词 Linearly Chirped waveform time-Bandwidth Product Frequency Multiplying Phase Coding
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内蒙古黑岱沟露天煤矿近场非天然地震事件的识别与应用
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作者 唐晓骞 张瑞新 +14 位作者 陈浩 刘芳 翟浩 舒雷 贾彦杰 周煊超 赵艳红 苏日亚 魏建民 尚立坚 郭伟 张茜 贾昕晔 吴卫远 戴怡茹 《地震研究》 北大核心 2026年第2期224-232,共9页
基于黑岱沟露天煤矿地震监测台网和内蒙古地震台网记录的地震、抛掷爆破、松动爆破和车辆振动共190次事件资料,从发震时刻、振幅比、时频特征、P波与S波最大振幅比(Pm/Sm)等方面,开展天然地震和非天然地震事件的识别与分析。结果表明:... 基于黑岱沟露天煤矿地震监测台网和内蒙古地震台网记录的地震、抛掷爆破、松动爆破和车辆振动共190次事件资料,从发震时刻、振幅比、时频特征、P波与S波最大振幅比(Pm/Sm)等方面,开展天然地震和非天然地震事件的识别与分析。结果表明:天然地震事件发生的时间具有很大的随机性,抛掷爆破、松动爆破和车辆振动事件的发震时间有一定的规律性。天然地震和非天然地震的时频空间分布具有相对独立、且界限分明的特征。Pm/Sm是识别矿区事件类型的较有效的判据,Pm/Sm均值方面,抛掷爆破>松动爆破>天然地震。 展开更多
关键词 黑岱沟露天煤矿 天然地震 非天然地震 波形特征 时频特征
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Sensitivity of MIMO STAP Radar with Waveform Diversity 被引量:1
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作者 孙进平 王国华 刘德生 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2010年第5期549-555,共7页
Space-time adaptive processing (STAP) is an effective method adopted in airborne radar to suppress ground clutter. Multi- ple-input multiple-output (M1MO) radar is a new radar concept and has superiority over conv... Space-time adaptive processing (STAP) is an effective method adopted in airborne radar to suppress ground clutter. Multi- ple-input multiple-output (M1MO) radar is a new radar concept and has superiority over conventional radars. Recent proposals have been applying STAP in MIMO configuration to the improvement of the performance of conventional radars. As waveforms transmitted by MIMO radar can be correlated or uncorrelated with each other, this article develops a unified signal model incor- porating waveforms for STAP in MIMO radar with waveform diversity. Through this framework, STAP performances are ex- pressed as functions of the waveform covariance matrix (WCM). Then, effects of waveforms can be investigated. The sensitivity, i.e., the maximum range detectable, is shown to be proportional to the maximum eigenvalue of WCM. Both theoretical studies and numerical simulation examples illustrate the waveform effects on the sensitivity of MIMO STAP radar, based on which we can make better trade-off between waveforms to achieve optimal system performance. 展开更多
关键词 RADAR MIMO space-time adaptive processing waveform diversity sensitivity waveform covariance matrix
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2000年易贡高速滑坡的动力学过程
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作者 江勇 白玲 +2 位作者 李鸿儒 陈治文 吴智超 《地球与行星物理论评(中英文)》 2026年第1期62-69,共8页
北京时间2000年4月9日19时58分,青藏高原东南缘林芝市波密县易贡地区发生大规模滑坡,造成约8 km^(2)的森林大范围受损,阻塞河道形成易贡湖.地震波形可以远程探测大规模滑坡事件的发生过程,有助于对滑坡事件的阶段性动力学参数进行定量分... 北京时间2000年4月9日19时58分,青藏高原东南缘林芝市波密县易贡地区发生大规模滑坡,造成约8 km^(2)的森林大范围受损,阻塞河道形成易贡湖.地震波形可以远程探测大规模滑坡事件的发生过程,有助于对滑坡事件的阶段性动力学参数进行定量分析.由于该事件规格大、能量强,使得易贡滑坡地震波形在远距离地震站上仍然有清晰的记录.本文利用中国地震台网宽频带地震台站波形数据对2000年易贡滑坡的动力学过程进行了分析,发现该事件持续时长约215 s,包括滑前启动阶段(约65 s)、主要滑动阶段(约90 s)和滑后调整阶段(约60 s).滑前调整阶段持续时间相对较长,低频信号较弱,而高频信号由弱逐渐增强,指示滑坡起始阶段主要以碎屑崩塌为主.主要滑动阶段进一步分为加速滑动和减速滑动过程,加速滑动过程高频信号和低频信号振幅较大,地形坡度较陡,物质在扎木弄沟中加速下滑,加速约35 s后达到最大速度约191 m/s,此时滑坡运动水平位移约3.1 km;相比而言,减速滑动过程高频和低频振动信号由强转弱,对应滑坡滑床变宽、坡度变缓,滑坡速度不断减小至0,约90 s后水平位移和垂直位移分别达到最大值约6.0 km和3.2 km.滑后调整阶段高低频信号振幅逐渐变弱,主要反映滑坡物质在扎木弄沟谷底部沉积.2000年易贡滑坡的体积和滑动速度明显大于青藏高原东南缘近期发生的其他滑坡事件,反映源区冰雪融水和降水导致沟谷沉积物下滑摩擦力减小,形成巨型堆积体,是易贡藏布河堵塞形成易贡湖的主要原因. 展开更多
关键词 2000年易贡滑坡 波形反演 受力时间函数
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基于时域电压推算比较的风电场送出线路保护新算法
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作者 李煜 李志为 +3 位作者 刘鸿基 肖成东 王勇 谭力铭 《湖南电力》 2026年第1期40-46,共7页
针对大规模风电接入电力系统后,传统线路保护算法难以适配系统特性变化的问题,提出一种基于时域电压推算比较的风电场送出线路保护方法。首先,基于电阻电感模型(resistor inductor based model,RL模型)构建线路电压的时域推算模型,分别... 针对大规模风电接入电力系统后,传统线路保护算法难以适配系统特性变化的问题,提出一种基于时域电压推算比较的风电场送出线路保护方法。首先,基于电阻电感模型(resistor inductor based model,RL模型)构建线路电压的时域推算模型,分别求解线路中特征点的电压值。随后通过对两点电压推算结果的波形进行相关性分析,实现故障的精准识别。本文方法采用时域全量分析思路,可有效克服风电系统中撬棒动作、过渡电阻影响及风电场弱馈等特殊工况带来的干扰。为验证算法的性能,在RSCAD仿真平台搭建双馈风电场并网模型开展仿真分析,结果表明所提保护方法能够准确识别故障,验证了其有效性与适应性。 展开更多
关键词 风电场 电压波形 时域 电压推算
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A real time processing system of seismic waves using personal computers-Function and characteristics
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作者 范军 陈天长 +4 位作者 韩渭宾 曾健 长谷川昭 堀内茂木 郑斯华 《Acta Seismologica Sinica(English Edition)》 CSCD 1998年第3期106-110,共5页
Seismological Bureau of Sichuan Province, Chengdu 610041, China2) Center for Analysis and Prediction, State Seismological Bureau, Beijing 100036, China3) Observation Center for Prediction of Earthquakes and Volcanic E... Seismological Bureau of Sichuan Province, Chengdu 610041, China2) Center for Analysis and Prediction, State Seismological Bureau, Beijing 100036, China3) Observation Center for Prediction of Earthquakes and Volcanic Eruptions, Faculty of Sciences, Tohoku University, Sendai 98077, Japan 展开更多
关键词 seismic wave real time processing realtime waveform display AR model the Akaike′s information criteria (AIC)
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多维相位编码调制的可重构MIMO SAR方案
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作者 彭武林 王伟 魏屹海 《电光与控制》 北大核心 2026年第4期90-96,共7页
回波分离一直是多发多收(MIMO)合成孔径雷达(SAR)领域的研究热点,数字波束形成(DBF)是回波分离的关键技术,但通常有较高的复杂度。提出一种多维相位编码调制的可重构MIMO SAR方案,大大简化了阵列配置,减少了计算开销,并降低了硬件的复... 回波分离一直是多发多收(MIMO)合成孔径雷达(SAR)领域的研究热点,数字波束形成(DBF)是回波分离的关键技术,但通常有较高的复杂度。提出一种多维相位编码调制的可重构MIMO SAR方案,大大简化了阵列配置,减少了计算开销,并降低了硬件的复杂度。传输的雷达波形采用正交频分复用(OFDM)和设计的空时分组编码(STC)进行双重调制。回波分离过程分为两个阶段:首先,通过空时编码解调,将接收到的混叠回波分离为不同的信号群;然后,利用俯仰向DBF和OFDM解调,对每个信号群内的混叠回波进一步分离。通过数值模拟和多场景仿真,对该方案进行了评估,结果表明其在资源受限的MIMO SAR系统中具有良好的应用潜力。 展开更多
关键词 多发多收合成孔径雷达 多维波形编码 数字波束形成 空时编码
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基于录波组网的开关特性监视方法及应用研究
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作者 袁梦 何焯贤 郭家劲 《仪器仪表用户》 2026年第2期76-78,共3页
针对电力系统10 kV及以上电压等级开关机构因机械卡阻、线圈老化、弹簧松弛等原因导致的慢分、慢合异常动作隐蔽性强且难以依靠传统监测手段及时、精准地发现与诊断的问题,本文提出一种基于录波组网的开关特性在线监视方法。该方法利用... 针对电力系统10 kV及以上电压等级开关机构因机械卡阻、线圈老化、弹簧松弛等原因导致的慢分、慢合异常动作隐蔽性强且难以依靠传统监测手段及时、精准地发现与诊断的问题,本文提出一种基于录波组网的开关特性在线监视方法。该方法利用故障录波自动解析开关量变位信息,精确提取分位与合位变位时间,并结合动态阈值机制与抗干扰算法,构建毫秒级动作特性辅助判据。在广州供电局变电管理三所的实践表明,该方法能有效识别开关异常动作,自动标记异常数据并关联保存录波文件,显著提升了隐患发现效率,为预防保护越级动作、控制故障范围扩大提供了技术支撑。 展开更多
关键词 录波组网 开关特性 动作时间 在线监测 异常判据
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Waveform digitization utilizing switched-capacitor arrays 被引量:1
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作者 WANG Jinhong ZHAO Lei +2 位作者 FENG Changqing LIU Shubin AN Qi 《Nuclear Science and Techniques》 SCIE CAS CSCD 2012年第2期109-113,共5页
Compared with traditional waveform digitization with flash-ADCs, waveform digitization with switched-capacitor arrays (SCAs) is able to achieve the sampling speed above 1 GS/s without degrading the analog to digital c... Compared with traditional waveform digitization with flash-ADCs, waveform digitization with switched-capacitor arrays (SCAs) is able to achieve the sampling speed above 1 GS/s without degrading the analog to digital conversion precision significantly. In this paper, we present the implementation of a fast waveform digitization system with the use of SCAs, and evaluate its performance of waveform digitization and the waveform timing. At about 5 GS/s, the dynamic input range of the digitizer is about 66 dB, and its timing precision is about 20 ps (RMS). 展开更多
关键词 波形数字化 开关电容阵列 数字化系统 数字化波形 数字转换器 转换精度 采样速度 执行情况
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Dynamic Characteristics of Double-Helical Planetary Gear Sets Under Time-Varying Mesh Stiffness 被引量:3
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作者 He Lin Sanmin Wang +2 位作者 Earl HDowell Jincheng Dong Cong Ma 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2016年第4期44-51,共8页
Internal and external meshes are two of primary excitation sources which induce vibration while double-helical planetary gear sets are in transmission. Based on the analysis of tooth movement principle,three cases of ... Internal and external meshes are two of primary excitation sources which induce vibration while double-helical planetary gear sets are in transmission. Based on the analysis of tooth movement principle,three cases of mesh stiffness are derived via investigating the length of action lines,and catalogued in terms of β < β0,β = β0and β > β_0. The simulation demonstrates mesh stiffness between gear pairs performs as a trapezoid waveform( TW) and changes along with the line of action simultaneously,total mesh stiffness comes from the superposition of each engaged gear. While governing equations of motion contained 16 DOFs( degree of freedom) are constructed and effectively solved through the combination of numerical approaches. Comparing with sinusoidal waveform mesh stiffness( SW),the results show that dynamical factors and perturbation under the excitation of TW( β < β_0) are greater and remarkable than that from SW,with respect to the mean dynamic factors about 1. 51 and 1. 28,respectively. The fluctuation response between ring- planet( R- P) is stronger than sun-planet( S-P) which is also validated by both approach studies,frequency spectra analyses identifies larger distinct rotational resonance and more frequencies under TW excitation. 展开更多
关键词 time-VARYING mesh stiffness TRAPEZOID waveform mean DYNAMICAL factors frequency spectra
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Three-detector setup for PAL spectrometer based on DRS4 waveform digitizing board
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作者 安然 陈祥磊 +9 位作者 代传波 郭晓彬 龚玉巍 李清华 任才 刘艳芬 郭俊清 丛龙翰 叶邦角 郭智荣 《Nuclear Science and Techniques》 SCIE CAS CSCD 2015年第4期57-60,共4页
A digital three-detector positron lifetime spectrometer was developed.It consists of a DRS4 waveform digitizing board and three La Br3scintillation detectors coupled to XP2020Q photomultiplier tubes.DRS4 waveform digi... A digital three-detector positron lifetime spectrometer was developed.It consists of a DRS4 waveform digitizing board and three La Br3scintillation detectors coupled to XP2020Q photomultiplier tubes.DRS4 waveform digitizing allows data sampling at up to 5 GSPS with high amplitude resolution,with good time scale linearity and stability.In the triple-coincidence,the new system could reach a 195 ps time resolution,which is better than the conventional analog apparatus with the same detectors.This spectrometer can be applied to the other scintillation timing measurements with picoseconds accuracy. 展开更多
关键词 闪烁探测器 波形数字化 数字化板 光谱仪 PAL 设置 正电子寿命 光电倍增管
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Frequency-time Domain Shielding Effectiveness of Materials and Their Strong Electromagnetic Field Test 被引量:1
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作者 ZHANG Long WEI Guanghui +3 位作者 FAN Lisi HU Xiaofeng ZHAO Yang ZHANG Yongqiang 《高电压技术》 EI CAS CSCD 北大核心 2013年第10期2398-2402,共5页
To describe the shielding ability of materials accurately and comprehensively,the frequency-domain and time-domain shielding effectiveness(SE) of material is investigated.The relevance between them was analyzed based ... To describe the shielding ability of materials accurately and comprehensively,the frequency-domain and time-domain shielding effectiveness(SE) of material is investigated.The relevance between them was analyzed based on the minimum phase method,and the time-domain SE can be derived from frequency-domain SE.The SE of an energy selective surface(ESS) made of a novel material is investigated,and the relationship between SE and radiation field intensity are analyzed.The results show that not only material,but also the intensity of radiation electric field shows influence on SE in its frequency; for some materials,the dependence of SE on radiation electric field intensity needs to be considered.Therefore,it is necessary to research on the SE of shielding material in high-intensity electromagnetic environment. 展开更多
关键词 新型材料 屏蔽效能 磁场测试 时间域 频率 强电 电场强度 遮蔽能力
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基于单孔试验的露天矿山减振延期时间优化
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作者 李洪伟 许博 +4 位作者 梁昊 储亚坤 苏洪 宋宝露 胡子杰 《金属矿山》 北大核心 2025年第11期185-193,共9页
针对某砂石骨料矿山减振延期时间选取的实际问题,设计了小直径炮孔单孔爆破振动试验,基于Matlab软件对单孔爆破波形数据进行叠加分析,研究了不同延期时间下的爆破振动强度和频率变化特性。并通过工业电子雷管精准控制的爆破试验,验证分... 针对某砂石骨料矿山减振延期时间选取的实际问题,设计了小直径炮孔单孔爆破振动试验,基于Matlab软件对单孔爆破波形数据进行叠加分析,研究了不同延期时间下的爆破振动强度和频率变化特性。并通过工业电子雷管精准控制的爆破试验,验证分析了不同延时时间下的峰值振动速度和频率特征。研究表明:(1)小直径炮孔单孔试验爆破振动在35m和55m爆心距的主振周期分别为13~18 ms、18~26 ms,选取单孔振动波叠加表明,叠加后最优减振延期不在主振周期范围内,而在T/3~2T/3(T为周期)区间;(2)不同延期时间、不同孔数叠加下均存在有利于减振的延期区间,综合峰值振动速度、主频因素确定了试验矿山的最佳降振延期时间为7~10 ms;(3)以矿山边坡为保护对象设计和开展现场试验,通过峰值振动速度、主频以及小波能量分析等多角度确定了40 ms具有较好的降振特性。研究结果对于从被保护物安全出发,寻求经济合理、有害效应较小的多孔延期爆破方法具有一定的参考意义。 展开更多
关键词 爆破振动 单孔试验 延期时间 波形叠加 干扰降振
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Research on a Method to Increase Waveform Capture Rate
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作者 Qin-chuan Zhang Min Li 《通讯和计算机(中英文版)》 2011年第12期1101-1107,共7页
关键词 波形捕获速率 数字存储示波器 随机过程理论 波形检测 映射技术 统计直方图 外部存储器 捕获率
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基于基准模态的日功率波形不确定性量化评估分析方法
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作者 严干贵 邢奥岚 +3 位作者 穆钢 陈璐 赵聚乐 詹朔 《电力系统自动化》 北大核心 2025年第11期29-36,共8页
高比例可再生能源电力系统中注入功率不确定性导致功率平衡难,认识系统注入功率的不确定性是合理配置调节资源、保障系统供需平衡的关键。文中从系统运行角度出发,以日功率波形为研究要素,提出一种基于基准模态的日功率波形不确定性量... 高比例可再生能源电力系统中注入功率不确定性导致功率平衡难,认识系统注入功率的不确定性是合理配置调节资源、保障系统供需平衡的关键。文中从系统运行角度出发,以日功率波形为研究要素,提出一种基于基准模态的日功率波形不确定性量化评估方法,依据日功率波形与基准模态功率波形之间的偏差来度量日功率波动的不稳定程度,据此分析负荷、风电、光伏等多类型日功率波形的不确定性特征。根据多类型日功率波形汇聚后总被动日功率波形与其基准模态功率波形之间的偏差,定量评估了风电、光伏联网带来的系统调节功率和调节电量的需求,为高比例可再生能源电力系统调节资源需求评估提供了理论指导。 展开更多
关键词 新型电力系统 高比例可再生能源 日功率波形 时序分布 不确定性 基准模态 量化评估
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基于连锁电压形态辨识的大规模新能源外送系统单相故障性质识别方法
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作者 李振兴 朱益 +4 位作者 安喆 翁汉琍 李振华 王秋杰 谭洪 《中国电机工程学报》 北大核心 2025年第22期8819-8831,I0013,共14页
针对传统故障性质识别方案难以适应大规模外送系统电源侧新能源集群接入的问题,提出一种基于连锁电压形态辨识的故障性质识别方法。首先,明确非全相运行的电压特性以及新能源电源谐波馈出机理,关注新能源谐波作用下的电压波形总体特征,... 针对传统故障性质识别方案难以适应大规模外送系统电源侧新能源集群接入的问题,提出一种基于连锁电压形态辨识的故障性质识别方法。首先,明确非全相运行的电压特性以及新能源电源谐波馈出机理,关注新能源谐波作用下的电压波形总体特征,发现在瞬时性故障熄弧前后,线路单端电压存在显著的固有形态差异,而永久性故障的电压形态差异极小;其次,通过论证选取特征形态基准,连续扫描并计算电压差积分有效值(root-mean-square,RMS),稳定表征电压形态差异,构建基于自适应阈值的故障性质识别方法;最后,基于PSCAD的仿真验证表明,该方法不限制线路并联电抗器的配置情况,可靠性高,具备良好的抗噪能力,且不受故障位置、过渡电阻和新能源渗透率的影响,能够在电源侧新能源集群接入时实现故障性质的准确识别。 展开更多
关键词 新能源集群 故障性质识别 熄弧时刻 线路端电压 形态辨识
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