Power transformer is a core equipment of power system, which undertakes the important functions of power transmission and transformation, and its safe and stable operation has great significance to the normal operatio...Power transformer is a core equipment of power system, which undertakes the important functions of power transmission and transformation, and its safe and stable operation has great significance to the normal operation of the whole power system. Due to the complex structure of the transformer, the use of single information for condition-based maintenance (CBM) has certain limitations, with the help of advanced sensor monitoring and information fusion technology, multi-source information is applied to the prognostic and health management (PHM) of power transformer, which is an important way to realize the CBM of power transformer. This paper presents a method which combine deep belief network classifier (DBNC) and D-S evidence theory, and it is applied to the PHM of the large power transformer. The experimental results show that the proposed method has a high correct rate of fault diagnosis for the power transformer with a large number of multi-source data.展开更多
China's traditional urban land system is established in highly centralized planned economy. This system negates functions of value law and economic law fundamentally,so it is not favorable for establishment of mar...China's traditional urban land system is established in highly centralized planned economy. This system negates functions of value law and economic law fundamentally,so it is not favorable for establishment of market mechanism and development of market economy. This study took Marx's ground rent theory as guidance,combined existing problems of China's land use system,and made analysis on innovation of China's urban land system from property right system,land market and land price.展开更多
Marx's theory of ground rent is an indispensable part of Marx's economic theory. It is essential to grasp scientific connotation of Marx's theory of ground rent,and actively explore and study theories and ...Marx's theory of ground rent is an indispensable part of Marx's economic theory. It is essential to grasp scientific connotation of Marx's theory of ground rent,and actively explore and study theories and policies of socialist ground rent and nationalization of land through combining the certainty of existence of ground rent and actual situations of nationalization of land in China.展开更多
>Transformer faults are quite complicated phenomena and can occur due to a variety of reasons.There have been several methods for transformer fault synthetic diagnosis,but each of them has its own limitations in re...>Transformer faults are quite complicated phenomena and can occur due to a variety of reasons.There have been several methods for transformer fault synthetic diagnosis,but each of them has its own limitations in real fault diagnosis applications.In order to overcome those shortcomings in the existing methods,a new transformer fault diagnosis method based on a wavelet neural network optimized by adaptive genetic algorithm(AGA)and an improved D-S evidence theory fusion technique is proposed in this paper.The proposed method combines the oil chromatogram data and the off-line electrical test data of transformers to carry out fault diagnosis.Based on the fusion mechanism of D-S evidence theory,the comprehensive reliability of evidence is constructed by considering the evidence importance,the outputs of the neural network and the expert experience.The new method increases the objectivity of the basic probability assignment(BPA)and reduces the basic probability assigned for uncertain and unimportant information.The case study results of using the proposed method show that it has a good performance of fault diagnosis for transformers.展开更多
Alice Walker is widely recognized as one of significant African-American writers and her most prominent work, The Color Purple, has won three awards altogether: the Pulitzer Prize, the America Book Award as well as th...Alice Walker is widely recognized as one of significant African-American writers and her most prominent work, The Color Purple, has won three awards altogether: the Pulitzer Prize, the America Book Award as well as the National Book Critics Circle Award nomination. It tells the story of how a submissive black girl named Celie undergoes the double oppression of racism and sexism at first, but transforms into an economically andmentally independent black woman eventually. This thesis will analyze Celie's psychological transformation from the perspective of Freud's personality theory and concludes that internal factors for Celie's psychological transformation areof great referential significance for all the women to explore their way to liberation.展开更多
A quantum time-dependent spectrum analysis, or simply, quantum spectral analysis (QSA) is presented in this work, and it’s based on Schrödinger’s equation. In the classical world, it is named frequency in t...A quantum time-dependent spectrum analysis, or simply, quantum spectral analysis (QSA) is presented in this work, and it’s based on Schrödinger’s equation. In the classical world, it is named frequency in time (FIT), which is used here as a complement of the traditional frequency-dependent spectral analysis based on Fourier theory. Besides, FIT is a metric which assesses the impact of the flanks of a signal on its frequency spectrum, not taken into account by Fourier theory and lets alone in real time. Even more, and unlike all derived tools from Fourier Theory (i.e., continuous, discrete, fast, short-time, fractional and quantum Fourier Transform, as well as, Gabor) FIT has the following advantages, among others: 1) compact support with excellent energy output treatment, 2) low computational cost, O(N) for signals and O(N2) for images, 3) it does not have phase uncertainties (i.e., indeterminate phase for a magnitude = 0) as in the case of Discrete and Fast Fourier Transform (DFT, FFT, respectively). Finally, we can apply QSA to a quantum signal, that is, to a qubit stream in order to analyze it spectrally.展开更多
Xi Jinping's theory on ecological progress expands and deepens Marx's views on ecology and spells out the five dialectics between economic development and ecological conservation, the will of the nation and th...Xi Jinping's theory on ecological progress expands and deepens Marx's views on ecology and spells out the five dialectics between economic development and ecological conservation, the will of the nation and the will of the people, Chinese characteristics and global approaches, cultural concepts and institutional design, as well as the community of life and the community of shared future for mankind. It carries significance for our time and is weighted with theoretical value. At this stage, learning and studying the dialectics and value orientation of Xi Jinping's theory on ecological progress offers scientific guidance and value-based directions for China's efforts to promote an ecological civilization.展开更多
By using integral transform methods, the Green(s functions of horizontal harmonic force applied at the interior of the saturated half-space soil are obtained in the paper. The general solutions of the Biot dynamic equ...By using integral transform methods, the Green(s functions of horizontal harmonic force applied at the interior of the saturated half-space soil are obtained in the paper. The general solutions of the Biot dynamic equations in frequency domain are established through the use of Hankel integral transforms technique. Utilizing the above- mentioned general solutions, and the boundary conditions of the surface of the half-space and the continuous conditions at the plane of the horizontal force, the solutions of the boundary value problem can be determined. By the numerical inverse Hankel transforms method, the Green(s functions of the harmonic horizontal force are obtainable. The degenerate case of the results deduced from this paper agrees well with the known results. Two numerical examples are given in the paper.展开更多
文摘Power transformer is a core equipment of power system, which undertakes the important functions of power transmission and transformation, and its safe and stable operation has great significance to the normal operation of the whole power system. Due to the complex structure of the transformer, the use of single information for condition-based maintenance (CBM) has certain limitations, with the help of advanced sensor monitoring and information fusion technology, multi-source information is applied to the prognostic and health management (PHM) of power transformer, which is an important way to realize the CBM of power transformer. This paper presents a method which combine deep belief network classifier (DBNC) and D-S evidence theory, and it is applied to the PHM of the large power transformer. The experimental results show that the proposed method has a high correct rate of fault diagnosis for the power transformer with a large number of multi-source data.
文摘China's traditional urban land system is established in highly centralized planned economy. This system negates functions of value law and economic law fundamentally,so it is not favorable for establishment of market mechanism and development of market economy. This study took Marx's ground rent theory as guidance,combined existing problems of China's land use system,and made analysis on innovation of China's urban land system from property right system,land market and land price.
文摘Marx's theory of ground rent is an indispensable part of Marx's economic theory. It is essential to grasp scientific connotation of Marx's theory of ground rent,and actively explore and study theories and policies of socialist ground rent and nationalization of land through combining the certainty of existence of ground rent and actual situations of nationalization of land in China.
基金Project Supported by National Natural Science Foundation of China （ 50777069 ）.
文摘>Transformer faults are quite complicated phenomena and can occur due to a variety of reasons.There have been several methods for transformer fault synthetic diagnosis,but each of them has its own limitations in real fault diagnosis applications.In order to overcome those shortcomings in the existing methods,a new transformer fault diagnosis method based on a wavelet neural network optimized by adaptive genetic algorithm(AGA)and an improved D-S evidence theory fusion technique is proposed in this paper.The proposed method combines the oil chromatogram data and the off-line electrical test data of transformers to carry out fault diagnosis.Based on the fusion mechanism of D-S evidence theory,the comprehensive reliability of evidence is constructed by considering the evidence importance,the outputs of the neural network and the expert experience.The new method increases the objectivity of the basic probability assignment(BPA)and reduces the basic probability assigned for uncertain and unimportant information.The case study results of using the proposed method show that it has a good performance of fault diagnosis for transformers.
文摘Alice Walker is widely recognized as one of significant African-American writers and her most prominent work, The Color Purple, has won three awards altogether: the Pulitzer Prize, the America Book Award as well as the National Book Critics Circle Award nomination. It tells the story of how a submissive black girl named Celie undergoes the double oppression of racism and sexism at first, but transforms into an economically andmentally independent black woman eventually. This thesis will analyze Celie's psychological transformation from the perspective of Freud's personality theory and concludes that internal factors for Celie's psychological transformation areof great referential significance for all the women to explore their way to liberation.
文摘A quantum time-dependent spectrum analysis, or simply, quantum spectral analysis (QSA) is presented in this work, and it’s based on Schrödinger’s equation. In the classical world, it is named frequency in time (FIT), which is used here as a complement of the traditional frequency-dependent spectral analysis based on Fourier theory. Besides, FIT is a metric which assesses the impact of the flanks of a signal on its frequency spectrum, not taken into account by Fourier theory and lets alone in real time. Even more, and unlike all derived tools from Fourier Theory (i.e., continuous, discrete, fast, short-time, fractional and quantum Fourier Transform, as well as, Gabor) FIT has the following advantages, among others: 1) compact support with excellent energy output treatment, 2) low computational cost, O(N) for signals and O(N2) for images, 3) it does not have phase uncertainties (i.e., indeterminate phase for a magnitude = 0) as in the case of Discrete and Fast Fourier Transform (DFT, FFT, respectively). Finally, we can apply QSA to a quantum signal, that is, to a qubit stream in order to analyze it spectrally.
基金included in"Studies on Consumption Crisis and Transformation from an Ecological Perspective"(14BKS032)a program supported by the National Social Sciences Fund+3 种基金"Studies on Education of Ecological Civilization-Taking Heilongjiang as an Example"(12YJAZH006)a program supported by the Ministry of Education’s Humanities and Social Sciences Research Fundand"Studies on the Building of a Forest-themed Culture from an Ecological Perspective"(2572014AC02)a program supported by the Central Special Fund for Basic Research at Universities
文摘Xi Jinping's theory on ecological progress expands and deepens Marx's views on ecology and spells out the five dialectics between economic development and ecological conservation, the will of the nation and the will of the people, Chinese characteristics and global approaches, cultural concepts and institutional design, as well as the community of life and the community of shared future for mankind. It carries significance for our time and is weighted with theoretical value. At this stage, learning and studying the dialectics and value orientation of Xi Jinping's theory on ecological progress offers scientific guidance and value-based directions for China's efforts to promote an ecological civilization.
基金State Natural Science Foundation (59879012) and Doctoral Foundation from State Education Commission (98024832).
文摘By using integral transform methods, the Green(s functions of horizontal harmonic force applied at the interior of the saturated half-space soil are obtained in the paper. The general solutions of the Biot dynamic equations in frequency domain are established through the use of Hankel integral transforms technique. Utilizing the above- mentioned general solutions, and the boundary conditions of the surface of the half-space and the continuous conditions at the plane of the horizontal force, the solutions of the boundary value problem can be determined. By the numerical inverse Hankel transforms method, the Green(s functions of the harmonic horizontal force are obtainable. The degenerate case of the results deduced from this paper agrees well with the known results. Two numerical examples are given in the paper.
