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The Time-Frequency Energy Attenuation Factor and Its Application on the Basis of Gauss Linear Frequency-Modulated Continuous Wavelet Transform
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作者 LiuXiqiang ShenPing +4 位作者 LiHong ShanChanglun JiAidong ZhangPing CaiMingjun 《Earthquake Research in China》 2004年第1期42-53,共12页
Based on the Gauss linear frequency modulated wavelet transform, a new characteristic index is presented, namely time frequency energy attenuation factor which can reflect the difference features of waveform in earthq... Based on the Gauss linear frequency modulated wavelet transform, a new characteristic index is presented, namely time frequency energy attenuation factor which can reflect the difference features of waveform in earthquake focus mechanism, wave traveling path and its attenuation characteristics in focal area or near field. In order to test its validity, we select the natural earthquakes and explosion or collapse events whose focus mechanisms vary obviously,and some natural earthquakes located at the same site or in a very small area. The study indicates that the time frequency energy attenuation factors of the natural earthquakes are obviously different with that of explosion or collapse events, and the change of the time frequency energy attenuation factors is relatively stable for the earthquakes under the normal seismicity background. Using the above mentioned method, it is expected to offer a useful criterion for strong earthquake prediction by continuous earthquake observation. 展开更多
关键词 Continuous wavelet transform Time frequency energy attenuation factor the space difference characteristics the time change characteristics
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From Nowhere Pioneer a New Path and Be of One Mind to Ascend the High——Profile of the Space Materials Research at Northwestern Polytechnical University 被引量:1
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作者 Jin Dashen Che Chengwei(Department of Engineering and Material Sciences, NSFC, Beijing 100085) 《Science Foundation in China》 CAS 2002年第2期52-53,共2页
At the end of 2001 National Natural Science Foundation of China (NSFC) organized a laboratory evaluation for Creative Research Groups, a pilot program launched in 2000, in the northwestern area of China and the evalua... At the end of 2001 National Natural Science Foundation of China (NSFC) organized a laboratory evaluation for Creative Research Groups, a pilot program launched in 2000, in the northwestern area of China and the evaluating team was deeply impressed by a young group, around 30 of average age, with their work and achievements, with their effort in pursuit of scientific truth and with their teamwork spirits. They all acknowl- 展开更多
关键词 From Nowhere Pioneer a New Path and Be of One Mind to Ascend the High Profile of the space Materials Research at Northwestern Polytechnical University PATH BE
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Localization of s-Wave and Quantum Effective Potential of a Quasi-free Particle with Position-Dependent Mass
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作者 JU Guo-Xing XIANG Yang REN Zhong-Zhou 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第5X期819-825,共7页
The properties of the 8-wave for a quasl-free partide with position-dependent mass (PDM) have been discussed in details. Differed from the system with constant mass in which the localization of the s-wave for the fr... The properties of the 8-wave for a quasl-free partide with position-dependent mass (PDM) have been discussed in details. Differed from the system with constant mass in which the localization of the s-wave for the free quantum particle around the origin only occurs in two dimensions, the quasi-free particle with PDM can experience attractive forces in D dimensions except D = 1 when its mass function satisfies some conditions. The effective mass of a particle varying with its position can induce effective interaction, which may be attractive in some cases. The analytical expressions of the eigenfunctions and the corresponding probability densities for the 8-waves of the two- and three-dimensional systems with a special PDM are given, and the existences of localization around the origin for these systems are shown. 展开更多
关键词 position-dependent mass S-WAVE Schrodinger equation dimensionality of the space LOCALIZATION EIGENFUNCTION probability density
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Star-shaped Differentiable Functions and Star-shaped Differentials
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作者 PAN SHAO-RONG ZHANG HONG-WEI ZHANG LI-WEI 《Communications in Mathematical Research》 CSCD 2010年第1期41-52,共12页
Based on the isomorphism between the space of star-shaped sets and the space of continuous positively homogeneous real-valued functions, the star-shaped differential of a directionally differentiable function is defin... Based on the isomorphism between the space of star-shaped sets and the space of continuous positively homogeneous real-valued functions, the star-shaped differential of a directionally differentiable function is defined. Formulas for star-shaped differential of a pointwise maximum and a pointwise minimum of a finite number of directionally differentiable functions, and a composite of two directionaUy differentiable functions are derived. Furthermore, the mean-value theorem for a directionaUy differentiable function is demonstrated. 展开更多
关键词 the space of star-shaped sets gauge function isometrical isomorphism directionally differentiable function star-shaped differential mean-value theorem
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Some Questions on the Space with an Indefinite Metric
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作者 严绍宗 《Acta Mathematica Sinica,English Series》 SCIE 1985年第4期285-293,共9页
§ 1. IntroductionIn Krein space H, the following results were proved in [1]: suppose that U is a unitary operator in H, and there exists a polynomial p(*) such that p(U} is quasi-nilpotent, then ([1], Theorem 2 (... § 1. IntroductionIn Krein space H, the following results were proved in [1]: suppose that U is a unitary operator in H, and there exists a polynomial p(*) such that p(U} is quasi-nilpotent, then ([1], Theorem 2 (ii)) there exists a decomposition n = ^@IIlt 展开更多
关键词 Some Questions on the space with an Indefinite Metric
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The Space Odyssey of Seeds
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作者 TANG YUANKAI 《Beijing Review》 2010年第17期43-43,共1页
Space plant-breeding technology is the future of agriculture chinese yews are on the verge of extinction. A chemical extracted from their barks is used to produce drugs for cancer treatment,
关键词 the space Odyssey of Seeds
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About Quantum Mechanics without Hamiltonians
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作者 Gustavo V. López 《Journal of Modern Physics》 2022年第5期671-681,共11页
An extension of Shr&ouml;dinger’s quantization on the space (x, p), where the Hamiltonian approach is needed, is made on the space (x, v) where the Hamiltonian approach is not needed at all. The purpose of this p... An extension of Shr&ouml;dinger’s quantization on the space (x, p), where the Hamiltonian approach is needed, is made on the space (x, v) where the Hamiltonian approach is not needed at all. The purpose of this paper is to give a possible extension of the actual formulation of the Quantum Mechanics, and this is achieved through a function K(x, v, t) which takes the place of the Hamiltonian on the Shr&ouml;dinger’s equation and has units of energy. This approach allows us to include the quantization of classical velocity depending problems (dissipative) and position depending mass variation problems. Some examples are given. 展开更多
关键词 Quantization in the space (x v) Mass Positiondepending Shrödinger’s Equation
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The Space Between my Grandparents Family Photos Take Grandchild on Emotional Journey into the Past
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作者 FANG ZHU ZHAO NING 《Women of China》 1994年第9期38-39,共2页
IN our family album, there is a picture of my grandfather, Fang Xiaoyue, and grandmother, Ma Junwan. The picture was taken in the 1920s when my grandparents were a newly married couple. It seemed to be in the afternoo... IN our family album, there is a picture of my grandfather, Fang Xiaoyue, and grandmother, Ma Junwan. The picture was taken in the 1920s when my grandparents were a newly married couple. It seemed to be in the afternoon in the photo, and in the background was an elegant garden, pale clouds in the sky, a rockery close by and a pavilion 展开更多
关键词 the space Between my Grandparents Family Photos Take Grandchild on Emotional Journey into the Past
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Structural Networks Constraints on Alteration and Mineralization Processes in the Jiaojia Gold Deposit, Jiaodong Peninsula, China 被引量:1
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作者 Huanlong Hu Shuangliang Liu +3 位作者 Hong-Rui Fan Kuifeng Yang Yabin Zuo Yachun Cai 《Journal of Earth Science》 SCIE CAS CSCD 2020年第3期500-513,共14页
Structural network studies could give appropriate opportunities to understanding structural/hydrothermal events,transportation of ore-forming fluids and water/rock interaction process.Four structural deformation/hydro... Structural network studies could give appropriate opportunities to understanding structural/hydrothermal events,transportation of ore-forming fluids and water/rock interaction process.Four structural deformation/hydrothermal events have been identified in the Jiaojia fault zone according to microtexture and deformation of quartz and feldspars.Plagioclase experienced ductile deformation period with bended polysynthetic twin stripes(>450℃)in the early stage,followed by K-feldspar alteration period with ductile-brittle deformation and subgrain rotation recrystallization of quartz(380-450℃).Then,sericitization period occurred extensive ductile-brittle deformation(350-420℃)and extensive subgrain rotation recrystallization with a little bulging recrystallization in quartz.In the last,gold precipitation-related pyrite-sericite-quartz alteration was dominated by brittle deformation(300-380℃)and total bulging recrystallization of quartz.From the K-feldspar alteration zone and sericitization zone to pyrite-sericitequartz alteration zone,fractal dimension values of dynamically recrystallized quartz grains increase from 1.07 and 1.24 to 1.32,the calculated paleo strain rate values of dynamically recrystallized quartz range from 10^-10^.7(380℃)-10^-9.6(450℃)and 10^-9.3(350℃)-10^-8.2(420℃)to 10^-9.5(300℃)-10^-8.0(380℃),and the paleo differential stress values increase from 36.9 and 39.3,to 121.3 MPa.The increase of fractal dimension values and decrease of grain size from pyrite-sericite-quartz alteration zone and sericitization zone to K-feldspar alteration zone decreased average water/rock ratio values,which could lead to different acidity and redox conditions of ore-forming fluids and mineralization differences.Two kinds of orecontrolling fractures have been distinguished which include the gentle dip types(18°-50°)with NW(315°-355°)and SW(180°-235°)dip hosting No.Ⅰorebodies and the steep dip types(74°-90°)with NE(45°-85°)and SE(95°-165°)dip hosting No.Ⅲorebodies.These faults/fractures crosscut altered Linglong granite of footwall of the Jiaojia fault zone as rhombohedrons that promoted the connection between fractures in the K-feldspar alteration zone and fluid flow passages near the main fault face.Research results indicate No.Ⅰand No.Ⅲorebodies should be derived from the same mineralization event and belong to different orebody types in different mineralization sites under the same structural networks. 展开更多
关键词 ore-controlling structural networks brittle-ductile deformation dynamic recrystallization of quartz fractal of quartz connection in the space Jiaojia Gold Deposit
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Polynomial solutions of quasi-homogeneous partial differential equations
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作者 LUO Xuebo ZHENG Zhujun Institute of Applied Mathematics, Northwestern Polytechnical University, Xi’an 710072, China Institute of Mathematics, Henan University, Kaifeng 475001, China 《Science China Mathematics》 SCIE 2001年第9期1148-1155,共8页
By means of a method of analytic number theory the following theorem is proved. Letp be a quasi-homogeneous linear partial differential operator with degreem,m > 0, w.r.t a dilation $\left\{ {\delta _\tau } \right\... By means of a method of analytic number theory the following theorem is proved. Letp be a quasi-homogeneous linear partial differential operator with degreem,m > 0, w.r.t a dilation $\left\{ {\delta _\tau } \right\}{\text{ }}_{\tau< 0} $ given by ( a1, …, an). Assume that either a1, …, an are positive rational numbers or $m{\text{ = }}\sum\limits_{j = 1}^n {\alpha _j \alpha _j } $ for some $\alpha {\text{ = }}\left( {\alpha _1 ,{\text{ }} \ldots {\text{ }},\alpha _n } \right) \in l _ + ^n $ Then the dimension of the space of polynomial solutions of the equationp[u] = 0 on ?n must be infinite 展开更多
关键词 quasi-homogeneous partial differential operator polynomial solution dimension of the space of solution method of analytic number theory
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