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高电压分相计量电能脉冲实现技术 被引量:3
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作者 郭琳云 尹项根 +1 位作者 严新荣 赵小林 《电力自动化设备》 EI CSCD 北大核心 2010年第4期112-114,共3页
由于高压电能表相间存在高压电位差,各相电能信息需通过光纤或无线通信等方式进行高速通信,从而造成硬件成本高。提出一种基于高电压分相电能计量和慢速率通信的电能脉冲实现方法,将A、C相分别计量的电能信息在B相电能综合单元中进行综... 由于高压电能表相间存在高压电位差,各相电能信息需通过光纤或无线通信等方式进行高速通信,从而造成硬件成本高。提出一种基于高电压分相电能计量和慢速率通信的电能脉冲实现方法,将A、C相分别计量的电能信息在B相电能综合单元中进行综合及累加,计算本周期的电能增量,并将电能增量所对应的电能脉冲在下个周期内均匀地发出。理论和实际均表明该实现方法能在保证智能设备计量准确度的同时,大幅降低硬件成本。 展开更多
关键词 电能脉冲 计量准确度 高电压 分相计量 通信
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射线型原油含气、含水率分析仪的原理及应用 被引量:2
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作者 任晓峰 李健 +2 位作者 孙慧 吴宝祥 孙志鹏 《自动化仪表》 CAS 2007年第10期11-13,17,共4页
针对油田原油生产计量中原油含水率和含气率难以监测的问题,采用射线型原油含气、含水率分析仪,解决了取样测量含水率代表性差的问题,克服了其它含水仪表由于水包油、油包水等因素造成的测量范围小、非线性误差大的不足,基本消除了含气... 针对油田原油生产计量中原油含水率和含气率难以监测的问题,采用射线型原油含气、含水率分析仪,解决了取样测量含水率代表性差的问题,克服了其它含水仪表由于水包油、油包水等因素造成的测量范围小、非线性误差大的不足,基本消除了含气对含水测量带来的误差。该仪表在长庆油田集油站和联合站、原油交接点以及单井计量中得到广泛应用,取得了较好的效果。 展开更多
关键词 射线型 原油含水率 测量 多相流 分相计量 分析仪
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DETERMINGING BPA UNDER UNCERTAINTY ENVIRONMENTS AND ITS APPLICATION IN DATA FUSION 被引量:15
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作者 Deng Yong Jiang Wen +2 位作者 Xu Xiaobin Li Qi Wang Dong 《Journal of Electronics(China)》 2009年第1期13-17,共5页
Dempster-Shafer (DS) theory of evidence has been widely used in many data fusion ap- plication systems. However, how to determine basic probability assignment, which is the main and the first step in evidence theory, ... Dempster-Shafer (DS) theory of evidence has been widely used in many data fusion ap- plication systems. However, how to determine basic probability assignment, which is the main and the first step in evidence theory, is still an open issue. In this paper, a new method to obtain Basic Probability Assignment (BPA) is proposed based on the similarity measure between generalized fuzzy numbers. In the proposed method, species model can be constructed by determination of the min, average and max value to construct a fuzzy number. Then, a new Radius Of Gravity (ROG) method to determine the similarity measure between generalized fuzzy numbers is used to calculate the BPA functions of each instance. Finally, the efficiency of the proposed method is illustrated by the classi- fication of Iris data. 展开更多
关键词 Data fusion Dempster-Shafer (DS) theory of evidence Basic Probability Assignment(BPA) Generalized fuzzy number Similarity measure
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COMBINATION OF ECMWF REANALYZED DAILY RAINFALL AND PENTAD CMAP IN CHINA
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作者 崔茂常 朱海 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2001年第3期200-207,共8页
In this study, 16 combinations of the ECMWF (European Centre for Medium Range Weather Forecast) reanalyzed daily rainfall and the pentad CMAP in China for the period 1980-1993(1 May-31 Dec.) were calculated. Correlati... In this study, 16 combinations of the ECMWF (European Centre for Medium Range Weather Forecast) reanalyzed daily rainfall and the pentad CMAP in China for the period 1980-1993(1 May-31 Dec.) were calculated. Correlation analysis was used to roughly evaluate daily rainfall for the whole of China and a combination of RPC (rotated principal component) and wavelet analyses was applied to data on observed and combined daily rainfall to obtain a detailed evaluation of the quality of these combined datasets in 6 selected major rainfall regions of eastern China. The results showed that except for intraweekly fluctuation, the best combination was roughly similar to or accorded well with observation in the aspects of space variation patterns and long period rainfall fluctuations related to monsoon onset and serious meteorologic disasters, indicating that this combination yielded better values of long term daily mean and standard deviation through the pentad CMAP (CPC Merged Analysis of Precipitation), and can also represent rainfall fluctuations through the reanalyzed daily rainfall. 展开更多
关键词 data combination daily rainfall in China ECMWF reanalysis pentad CMAP
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Phase Difference Method for DOA Estimation 被引量:2
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作者 陈志菲 孙进才 侯宏 《Journal of Marine Science and Application》 2010年第4期445-450,共6页
The phase difference method (PDM) is presented for the direction of arrival (DOA) estimation of the narrowband source. It estimates the DOA by measuring the reciprocal of the phase range of the sensor output spectra a... The phase difference method (PDM) is presented for the direction of arrival (DOA) estimation of the narrowband source. It estimates the DOA by measuring the reciprocal of the phase range of the sensor output spectra at the interest frequency bin. The peak width and variance of the PDM are presented. The PDM can distinguish closely spaced sources with different and unknown center frequencies as long as they are separated with at least one frequency bin. The simulation results show that the PDM has a better resolution than that of the conventional beamforming. 展开更多
关键词 direction of arrival(DOA) phase difference peak width variance RESOLUTION
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武汉地铁室分系统远程抄表创新及应用
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作者 郭轩 胡杰 +2 位作者 郭卫国 陈剑波 蔡明亮 《信息通信》 2019年第6期259-261,共3页
文章结合武汉铁塔地铁隧道室内分布系统建设经验,重点分析地铁隧道室分系统中常用电力计量方式面临的协调难、精度差、工作量大和效率低等问题,并针对性的提出了在区间机房中采用分相自动集中计量和依托FSU远程抄表的创新方案,该方案能... 文章结合武汉铁塔地铁隧道室内分布系统建设经验,重点分析地铁隧道室分系统中常用电力计量方式面临的协调难、精度差、工作量大和效率低等问题,并针对性的提出了在区间机房中采用分相自动集中计量和依托FSU远程抄表的创新方案,该方案能够很好的解决传统电力计量方式中区间开断点有源设备需分运营商计量以及后期维护抄表所面临的问题。该创新方案在武汉地铁隧室内分布系统建设中成功应用,验证了其在降本增效方面的作用,成为武汉铁塔地铁隧道室分系统建设项目中最重要的创新亮点。 展开更多
关键词 地铁隧道 室内分布系统 分相自动集中计量 远程抄表 通信链路FSU
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Statistical Separability of the World and Consistency Between Quantum Theory, Relativity, and Causality
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作者 ZHANG Qi-Ren 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第5期826-828,共3页
We show that the quantum world with non-local states and original statistics is statistically separable. According to relativistic dynamics, the super-luminal signal transmission is impossible. The present quantum the... We show that the quantum world with non-local states and original statistics is statistically separable. According to relativistic dynamics, the super-luminal signal transmission is impossible. The present quantum theory is therefore consistent with the relativity and the causality. 展开更多
关键词 statistical separability
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Theoretical Investigation of the Bonding Properties of Bis(glycinato) d8metal(II) Dihydrate Complexes Using Density Functional Theory
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作者 Bikele Mama Desire Younang Elie Penka Fowe Emmanuel 《Journal of Chemistry and Chemical Engineering》 2012年第5期475-483,共9页
Density functional theory (DFT) approach has been applied for the analysis of the bond between the [(H20)2] and the [M(gly)2] fragments in a series of trans and cis [M(gly)2[(H20)2] complexes. For comparativ... Density functional theory (DFT) approach has been applied for the analysis of the bond between the [(H20)2] and the [M(gly)2] fragments in a series of trans and cis [M(gly)2[(H20)2] complexes. For comparative purpose, both relativistic and non-relativistic calculations have been performed. The nature of the interaction between the [(H20)2] and [M(gly)2] fragments was investigated using energy decomposition analysis, Hirshfeld atomic charge variation, molecular orbital considerations and bond order decomposition analysis, respectively. Results reveal that the [(H20):]-[M(gly)2] interaction lies from the hydrogen bridge interaction between these fragments. The strength of the bonding increases in the order Ni2+ 〉 Pd2+ 〉 Pt2+ while the relativistic correction tends to strengthen the [(H2O)2---[M(gly)2] bond in the order Ni 〈 Pd 〈 Pt. 展开更多
关键词 Density functional theory transition metal complexes hydrogen bonds.
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Effects of source opacity and expansion on two-pion Bose-Einstein correlations 被引量:3
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作者 LI ShuXia SUN PuNan XIAO DeHang 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2011年第5期909-915,共7页
We examine two-pion Bose-Einstein correlations for partially coherent particle-emitting sources within quantum statistical formal- ism, where the sources are treated as classical currents with chaotic and coherent com... We examine two-pion Bose-Einstein correlations for partially coherent particle-emitting sources within quantum statistical formal- ism, where the sources are treated as classical currents with chaotic and coherent components. The two-pion correlation functions of the partially coherent sources contain a phase which is sensitive to the asymmetry of the source emission function. We investigate the influence of source opacity and expansion in high energy heavy ion collisions on the phase by Monte Carlo calculations. We find that these two physical effects shift the phase from zero. The Gaussian-formula fit results to the simulated two-pion correlation functions indicate that the opaque and expansion effects lead to a smaller interferometry radius Rout and a larger 2 parameter. 展开更多
关键词 two-pion correlation partially coherent sources asymmetry
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Numerical studies on weak and strong ignition induced by reflected shock and boundary layer interaction 被引量:1
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作者 Chengyang Huang Yuan Wang +2 位作者 Ralf Deiterding Dehai Yu Zheng Chen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2022年第2期24-34,I0001,共12页
In shock tube experiments,the interaction between the reflected shock and boundary layer can induce shock bifurcation and weak ignition.The weak ignition can greatly affect the ignition delay time measurement in a sho... In shock tube experiments,the interaction between the reflected shock and boundary layer can induce shock bifurcation and weak ignition.The weak ignition can greatly affect the ignition delay time measurement in a shock tube experiment.In this work,two-dimensional simulations considering detailed chemistry and transport are conducted to investigate the shock bifurcation and non-uniform ignition behind a retlected shock.The objectives are to interpret the formation of shock bifurcation induced by the reflected shock and boundary layer interaction and to investigate the weak ignition and its transition to strong ignition for both hydrogen and dimethyl ether.It is found that the non-uniform reflection of the incident shock at the end wall produces a wedge-shaped oblique shock foot at the wall.The wedge-shaped structure results in strong interactions between reflected shock and boundary layer,which induces the shock bifurcation.It is demonstrated that the local high-temperature spots at the foot of the bifurcated shock is caused by viscous dissipation and pressure work.As the post-reflected shock temperature increases,the transition from weak ignition to strong ignition in a stoichiometric hydrogen/oxygen mixture is observed.The relative sensitivity of ignition delay time to the post-rellected shock temperature is introduced to characterize the appearance of weak ignition behind the reflected shock.Unlike in the hydrogen/oxygen mixture,weak ignition is not observed in the stoichiometric dimethyl-ether/oxygen mixture since it has a relatively longer ignition delay time and smaller relative sensitivity. 展开更多
关键词 Shock tube Weak ignition Shock-houndary layer interaction
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