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Classification and Source Materials of Continental Crust Transformation Series Granitoids in South China 被引量:4
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作者 Liu Changshi Zhu Jinchu +1 位作者 Shen Weizhou Xu Shijin Department of Earth Sciences, Nanjing University, Nanjing, Jiangsu Jiang Minxi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1990年第3期287-298,共12页
The granitoids of the continental crust transformation series in South China may be divided into threetypes: (1) synorogenic migmatic and magmatic type. (2) anorogenic continental crust anatexis type, and (3)syncollis... The granitoids of the continental crust transformation series in South China may be divided into threetypes: (1) synorogenic migmatic and magmatic type. (2) anorogenic continental crust anatexis type, and (3)syncollision type. Based on the results of Sr and Nd isotopic determinations, the source material compositionof the three types of granitoids is calculated with crust-mantle binary mixing simulation. The calculations indi-cate that the granitoids of the first type consist of 78.6-89.7% upper crust endmember materials and15.0-10.3% depleted mantle endmember materials, the granitoids of the second type are composed of 63.7%upper crust endmember materials and 36.3% depleted mantle endmember materials, and those of the third type100% upper crust endmember materials. Hence. the source material composition of the granitoids of all thethree types is dominated by upper crust endmembers. 展开更多
关键词 Classification and Source Materials of Continental Crust Transformation series Granitoids in South China SOURCE
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Measurement of nuclides of uranium and thorium series of disequilibrium using γ-spectroscopy 被引量:2
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作者 刘广山 黄奕普 +1 位作者 李静 叶林 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2002年第4期505-517,共13页
The decay dynamic equations of two daughters were resolved as initial activities of daughters are not zero, and gave calculation formula of activities for measuring uranium and thorium series of disequilibrium using ... The decay dynamic equations of two daughters were resolved as initial activities of daughters are not zero, and gave calculation formula of activities for measuring uranium and thorium series of disequilibrium using γ-spectroscopy. 238U, 234Th, 226Ra, 222Rn, 228Ra, 228Th, 224Ra, 212Pb, 210Pb and 40K in two sediment samples were determined as application. 展开更多
关键词 Disequilibrium transformation series analysis of γ-spectrum
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SUMMATION OF TRIGONOMETRIC SERIES BY FOURIER TRANSFORMS
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作者 钱伟长 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第5期385-397,共13页
This paper gives the theorems concerning the summation of trigonometric series with the help of Fourier transforms. By means of the known results of Fourier transforms, many difficult and complex problems of summation... This paper gives the theorems concerning the summation of trigonometric series with the help of Fourier transforms. By means of the known results of Fourier transforms, many difficult and complex problems of summation of trigonometric series can be solved. This method is a comparatively unusual way to find the summation of trigonometric series, and has been used to establish the comprehensive table of summation of trigonometric series. In this table 10 thousand scries arc given, and most of them are new. 展开更多
关键词 exp SUMMATION OF TRIGONOMETRIC series BY FOURIER TRANSFORMS
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A Water Level Forecast of Pattani River in the Southern of Thailand by Deep Learning
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作者 Prattana Deeprasertkul Kanoksri Sarinnapakorn 《Journal of Computer and Communications》 2023年第8期14-28,共15页
Nowadays, the deep learning methods are widely applied to analyze and predict the trend of various disaster events and offer the alternatives to make the appropriate decisions. These support the water resource managem... Nowadays, the deep learning methods are widely applied to analyze and predict the trend of various disaster events and offer the alternatives to make the appropriate decisions. These support the water resource management and the short-term planning. In this paper, the water levels of the Pattani River in the Southern of Thailand have been predicted every hour of 7 days forecast. Time Series Transformer and Linear Regression were applied in this work. The results of both were the water levels forecast that had the high accuracy. Moreover, the water levels forecasting dashboard was developed for using to monitor the water levels at the Pattani River as well. 展开更多
关键词 Time series transformer Linear Regression Water Level Prediction Data Cleansing
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Materials Response to High Power Energy Lasers(A Short Course-Part V(b))
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作者 Bahman Zohuri 《Journal of Energy and Power Engineering》 2021年第7期253-285,共33页
As we have stated in conclusion of PART IV of these series including PART V,here in wrapping up and ending these series,we are producing with PART VI,which is nothing more than continuation of PART V.
关键词 Analytical solution finite difference and finite elements method Fourier series and Laplace transformation complex variables
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Materials Response to High Power Energy Lasers (A Short Course-Part V (a))
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作者 Bahman Zohuri 《Journal of Energy and Power Engineering》 2021年第6期202-230,共29页
As we have stated in conclusion of PART IV of these series,here in PART V,we will show how to find the solution for the governing equation of heat conduction as it was setup in PART IV,given the boundary and initial c... As we have stated in conclusion of PART IV of these series,here in PART V,we will show how to find the solution for the governing equation of heat conduction as it was setup in PART IV,given the boundary and initial conditions for Eq.(156)by means of exact and numerical methods.The different sections provided in here as PART V is consisting of a discussion of the approximate solution of the problem using mathematical tools and divided into four other sections parts as illustrated in this part.First four section namely 2.0,3.0,4.0 and 5.0 present an analytical method of the solution of the general governing equation using the Fourier theory.Section 6.0 is considering interaction of laser energy with materials using very short laser pulses and introduces electron-phonon theory approach to solve the heat transfer problem of the interaction of ultra-short pulses with the matter.Section 7.0 describes heating analysis with time-dependent pulse intensity and where evaporation is considered as the exclusive phenomenon taking place during the ablation process.Section 8.0 presents the heating analysis with pulsed laser heating process by considering both Fourier conduction and electron-phonon kinetic theory approaches.Finally,Section 9.0 consists of a discussion of the approximate solution of the problem using the Finite Difference Method(FDM)and Finite Element Method(FEM),and presents the computer solutions developed. 展开更多
关键词 Analytical solution finite difference and finite elements method Fourier series and Laplace Transformation complex variables
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Analysis of temperature time series based on Hilbert-Huang Transform 被引量:2
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作者 马皓 邱翔 +2 位作者 罗剑平 顾品强 刘宇陆 《Journal of Hydrodynamics》 SCIE EI CSCD 2015年第4期587-592,共6页
In this paper, with consideration of the nonlinear and non-stationary properties of the temperature time series, we employ the Hilbert-Huang Transform, based on the empirical mode decomposition(EMD), to analyze the ... In this paper, with consideration of the nonlinear and non-stationary properties of the temperature time series, we employ the Hilbert-Huang Transform, based on the empirical mode decomposition(EMD), to analyze the temperature time series from 1959 to 2012 in the Fengxian district of Shanghai, obtained from a certain monitoring station. The oscillating mode is drawn from the data, and its characteristics of the time series are investigated. The results show that the intrinsic modes of 1, 2 and 6 represent the periodic properties of 1 year, 2.5 years, and 27 years. The mean temperature shows periodic variations, but the main trend of this fluctuation is the rising of the temperature in the recent 50 years. The analysis of the reconstructed modes with the wave pattern shows that the variations are quite large from 1963 to 1964, from 1977 to 1982 and from 2003 to 2006, which indicates that the temperature rises and falls dramatically in these periods. The volatility from 1993 to 1994 is far more dramatic than in other periods. And the volatility is the most remarkable in recent 50 years. The log-linear plots of the mean time scales T and M show that each mode associated with a time scale almost twice as large as the time scale of the preceding mode. The Hilbert spectrum shows that the energy is concentrated in the range of low frequency from 0.05 to 0.1 Hz, and a very small amount of energy is distributed in the range of higher frequency over 0.1 Hz. In conclusion, the HHT is better than other traditional signal analysis methods in processing the nonlinear signals to obtain the periodic variation and volatility's properties of different time scales. 展开更多
关键词 atmospheric turbulence temperature time series empirical mode decomposition(EMD) Hilbert Huang Transform
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New Wavelet Theory and Application in Nondestructive Testing 被引量:1
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作者 张秀峰 施克仁 郑立男 《Tsinghua Science and Technology》 SCIE EI CAS 2004年第5期565-569,共5页
A new ultrasound signal processing model that provides fast real-time performance was devel- oped. The model is based on the “rotation angle series fast wavelet transform” algorithm developed for real- time digita... A new ultrasound signal processing model that provides fast real-time performance was devel- oped. The model is based on the “rotation angle series fast wavelet transform” algorithm developed for real- time digital signal processing. Instead of the traditional convolution-based algorithms, the algorithm uses a cascaded structure which can be quickly implemented on digital signal processors. The algorithm runs twice as fast as and is more flexible than the fast wavelet transform, and is applicable for multi-channel and phased array ultrasound systems. By using this algorithm, multi-channel ultrasound systems, including phased array ultrasound systems can have less complex software and hardware designs, lower cost, smaller size, and especially more powerful functions. 展开更多
关键词 WAVELET rotation angle series rotation angle series fast wavelet transform nondestructive testing ULTRASOUND
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