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关于邻近双星非保守性演化
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作者 Huang,RQ 《紫金山天文台台刊》 北大核心 1994年第2期126-140,共15页
关键词 双星 星系演化 非保守性
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代谢组学研究中数据处理新方法的应用 被引量:43
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作者 李晶 吴晓健 +1 位作者 刘昌孝 元英进 《药学学报》 CAS CSCD 北大核心 2006年第1期47-53,共7页
目的探索代谢组学研究中数据处理的新方法。方法本文提出了在代谢组学数据预处理中,用稳健PCA的方法进行离群样品点的诊断,用变量的类内差异和类间差异的比较来判断非保守性代谢组分,用尺度同一化的方法进行数据预处理来消除数据的尺度... 目的探索代谢组学研究中数据处理的新方法。方法本文提出了在代谢组学数据预处理中,用稳健PCA的方法进行离群样品点的诊断,用变量的类内差异和类间差异的比较来判断非保守性代谢组分,用尺度同一化的方法进行数据预处理来消除数据的尺度差异。并以Arabidopsis thaliana属的四个基因型的植株代谢组学的数据为例,用以上的方法进行数据预处理后再用PCA的方法分析。结果与结论研究表明这三种数据预处理方法的应用会明显的改善代谢组学生物信息学分析中聚类分析的结果和生物标志物识别的准确性及全面性。 展开更多
关键词 代谢组学 离群样本点诊断 非保守性代谢组分 数据尺度同一化 主成分分析法
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On Periodic Solution of Nonconservative Systems 被引量:2
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作者 李维国 陈昆亭 《Chinese Quarterly Journal of Mathematics》 CSCD 1997年第3期45-49, ,共5页
In this paper,we consider the following systems x″+ Bx′+ gradG(x,t) = 0.Weak sufficient condition for the existence of a unique 2π-periodic solution of the systems is given and the results in [1]~ [3],[7]~ [8]are c... In this paper,we consider the following systems x″+ Bx′+ gradG(x,t) = 0.Weak sufficient condition for the existence of a unique 2π-periodic solution of the systems is given and the results in [1]~ [3],[7]~ [8]are consequences of Theorem 2 in this paper if‖B‖2<1. 展开更多
关键词 nonconservative system periodic solution HOMEOMORPHISM
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Solitary Wave and Wavelet
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作者 LIUShi-Da FUZun-Tao LIUShi-Kuo XINGuo-Jun LIANGFu-Ming 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第3期335-338,共4页
In this paper,it is shown that the homoclinic orbits exist in iterated functional systems.so do the solitary wave structures.Moreover,Harr father wavelet,Mexican Cap wavelet,and other closed form wavelets have this so... In this paper,it is shown that the homoclinic orbits exist in iterated functional systems.so do the solitary wave structures.Moreover,Harr father wavelet,Mexican Cap wavelet,and other closed form wavelets have this solitary wave structure,too So wavelet is a certain kind of solitary wave. 展开更多
关键词 solitary waves WAVELET homoclinic orbit wavelet transform
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Properties of Parity Non-conserved and Parity Conserved States in Matrix Product Systems
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作者 祝敬敏 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第8期373-379,共7页
In terms of reflection transformation of a matrix product state (MPS), the parity of the MPS is defined. Based on the reflective parity non-conserved MPS pair we construct the even-parity state |ψe〉 and the odd-p... In terms of reflection transformation of a matrix product state (MPS), the parity of the MPS is defined. Based on the reflective parity non-conserved MPS pair we construct the even-parity state |ψe〉 and the odd-parity state |ψσ〉. It is interesting to find that the parity non-conserved reflective MPS pair have no long-range correlations; instead the even-parity state |ψe〉 and the odd-parity state |ψo〉 constructed from them have the same long-range correlations for the parity non-conserved block operators. Moreover, the entanglement between a block of n contiguous spins and the rest of the spin chain for the states |ψe〉 and |ψo〉 is larger than that for the reflective MPS pair except for n = 1, and the difference of them approaches 1 monotonically and asymptotically from 0 as n increases from 1. These characteristics indicate that MPS parity as a conserved physical quantity represents a kind of coherent collective quantum mode, and that the parity conserved MPSs contain more correlation, coherence, and entanglement than the parity non-conserved ones. 展开更多
关键词 matrix product state parity operator long-range correlation entanglement entropy
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Non-linear and non-conservative quasi-variational principle of flexible body dynamics and application in spacecraft dynamics 被引量:10
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作者 LIANG LiFu SONG HaiYan 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第11期2192-2199,共8页
The law of conservation of energy is one of the most fundamental laws of nature.According to the law of the conservation of energy,the non-linear and non-conservative quasi-variational principle of flexible body dynam... The law of conservation of energy is one of the most fundamental laws of nature.According to the law of the conservation of energy,the non-linear and non-conservative quasi-variational principle of flexible body dynamics is established.The physical meaning of the quasi-stationary value conditions has been explained in non-linear and non-conservative flexible body dynamics.In the case study,the application in spacecraft dynamics is researched. 展开更多
关键词 NON-LINEAR non-conservative variational principle spacecraft dynamics flexible body
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Corrected Nonconservative Schemes
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作者 Olivier PIRONNEAU 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2006年第5期539-548,共10页
Derivatives of discontinuities being Dirac singularities, it is usually not possible to multiply them by discontinuous functions. However in the context of conservation laws we have shown in a recent paper that it can... Derivatives of discontinuities being Dirac singularities, it is usually not possible to multiply them by discontinuous functions. However in the context of conservation laws we have shown in a recent paper that it can be done. We shall make use of this new framework to revisit some upwind methods, mostly characteristic schemes, and show that they can be corrected to be conservative and to work on difficult problems such as Euler's equations for fluids. Numerous numerical results are given. 展开更多
关键词 UPWINDING Non-conservative Finite volume method Compressible Euler
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Noether symmetries of the nonconservative and nonholonomic systems on time scales 被引量:55
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作者 CAI PingPing FU JingLi GUO YongXin 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第5期1017-1028,共12页
In this paper we give a new method to investigate Noether symmetries and conservation laws of nonconservative and nonholonomic mechanical systems on time scales , which unifies the Noether's theories of the two ca... In this paper we give a new method to investigate Noether symmetries and conservation laws of nonconservative and nonholonomic mechanical systems on time scales , which unifies the Noether's theories of the two cases for the continuous and the discrete nonconservative and nonholonomic systems. Firstly, the exchanging relationships between the isochronous variation and the delta derivatives as well as the relationships between the isochronous variation and the total variation on time scales are obtained. Secondly, using the exchanging relationships, the Hamilton's principle is presented for nonconservative systems with delta derivatives and then the Lagrange equations of the systems are obtained. Thirdly, based on the quasi-invariance of Hamiltonian action of the systems under the infinitesimal transformations with respect to the time and generalized coordinates, the Noether's theorem and the conservation laws for nonconservative systems on time scales are given. Fourthly, the d'Alembert-Lagrange principle with delta derivatives is presented, and the Lagrange equations of nonholonomic systems with delta derivatives are obtained. In addition, the Noether's theorems and the conservation laws for nonholonomic systems on time scales are also obtained. Lastly, we present a new version of Noether's theorems for discrete systems. Several examples are given to illustrate the application of our results. 展开更多
关键词 time scale Lagrange equation delta derivative Noether's theorem nonconservative and nonholonomic system
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Spontaneous atraumatic dislocation of sternoclavicu- lar joint in Reiter's syndrome 被引量:2
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作者 Vijay Kumar Digge Sanjay Meena +1 位作者 Shah Alam Khan Ravi Mittal 《Chinese Journal of Traumatology》 CAS 2012年第4期251-253,共3页
Reactive arthritis or Reiter's syndrome characteristically affects the joint of the lower limb in an asymmetrical pattern. Usually it does not affect the axial skeleton or upper limbs. Although cases of atraumatic at... Reactive arthritis or Reiter's syndrome characteristically affects the joint of the lower limb in an asymmetrical pattern. Usually it does not affect the axial skeleton or upper limbs. Although cases of atraumatic at- lantoaxial subluxations have been reported, no case of spon- taneous sternoclavicular dislocation in Reiter's syndrome has been reported. This paper describes a case of a 26 year old male patient who developed a spontaneous posterior sternoclavicular joint dislocation. No attempt of reduction was made and the patient was managed conservatively with good results. 展开更多
关键词 Arthritis reactive Sternoclavicularjoint Dislocations
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