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models　FOR　π－π　INTERACroNS　IN　“MOLECULARMETALS”　IONIZATION　ENERGIES，ELECTRONIC　STRUCTURE　AND　THROVGH－SPACE／THROUGH－BOND　INTERACTIONS　IN　［2，2］　PARACYCLOPHANE

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维普期刊数据库

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Chinese Chemical Letters 1994年第3期5卷 221-224页

作者： Han Xing LIU (Anvanced Materials Research Institute, Wuhan University of Technology, Wuban, 430070)Chia Chung SUN(Institute of Theoretical Chemistry, Jilin University, Cbangchun, 130021)

The through-space and through-bond interactions of molecular orbitals in [2,2] paracyclophane are studied by the approved MS-X. method with overlapping atomic-sphere. The calculation results show the through-space interactions are exponential flareout with increasing of the distance of two orbitals, *** through-space interactions and through-bond interactions are sizable but those two interactions oppose each other causing the net splitting to be small. Transition-state procedure was used to calculate ionization potentials, the results are in agreement with the PE-spectra.

关键词： SPACE INTERACTIONS ELECTRONIC ENERGIES FOR AND INTERACroNS IONIZATION models PARACYCLOPHANE

OUTLIER DETECTION AND RELIABILITY OF ADJUSTMENT models WITH SINGULAR COVARIANCE MATRICES

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Geo-Spatial Information Science 1998年第1期1卷 55-59页

作者： WANG Jinling[a] CHENG Yongqi TAO Benzao [a] School of Geo-science and Surveying Engineering WTUSM Wuhan China 430079

Up to now,outlier detection and reliability theory are generallybased on the regular Gauss-Markov models,in which the covariance matrix of ob-servations is positively *** the adjustment models with singular covari-ance matrix,the statistics for outlier detection are derived by the *** reliability theory is *** the application of the theory isdemonstrated with a practical example.

关键词： singular adjustment models outliers reliability theory

Diffusion MRI studies of experimental animal models and patients with stroke

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Chinese Medical Journal 1999年第2期 81-86页

作者： Zheng Guang Chen, Tieqiang Li and Tomas Hindmarsh

Abstract Purpose This overview summarises the diffusion magnetic resonance imaging (MRI) results both from the experimental animal model studies and clinical investigations in acute cerebral ischemic *** Sources An English literature searched using MEDLINE (1990-1997).Study Selection Over 80 papers and reviews published in the last eight years and our partial results were *** and Conclusions Diffusion weighted magnetic resonance imaging (DWI) has been extensively used to study acute cerebral ischemia both in experimental animal models and in patients. DWI yields signal intensity contrast modulated by water molecular self diffusion. By recording a series of DWI with different amplitudes of the displacement encoding gradient, the apparent diffusion coefficient (ADC) can be quantitatively mapped. DWI combined with quantitative ADC mapping can provide earlier and more precise evaluation of the ischemic zones. However, the biophysical mechanisms behind the decreased ADC in acute cerebral ischemia are still not fully understood.

关键词： MRI studies experimental animal models Diffusion and

Generalized Linear models With Random Effects: Unified Analysis Via H-likelihood (Chapman & Hall/CRC Monographs On Statistics & Applied Probability) 1st

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ASYMPTOTIC PROPERTIES OF MLE IN EXPONENTIAL FAMILY NONLINEAR models

丛书名： Monographs on statistics and applied probability

2006年

作者： Youngjo Lee John A. Nelder Yudi Pawitan

ISBN: (纸本)9781584886310

Since their introduction in 1972, generalized linear models (GLMs) have proven useful in the generalization of classical normal models. Presenting methods for fitting GLMs with random effects to data, Generalized Linear models with Random Effects: Unified Analysis via H-likelihood explores a wide range of applications, including combining information over trials (meta-analysis), analysis of frailty models for survival data, genetic epidemiology, and analysis of spatial and temporal models with correlated *** by pioneering authorities in the field, this reference provides an introduction to various theories and examines likelihood inference and GLMs. The authors show how to extend the class of GLMs while retaining as much simplicity as possible. By maximizing and deriving other quantities from h-likelihood, they also demonstrate how to use a single algorithm for all members of the class, resulting in a faster algorithm as compared to existing alternatives. Complementing theory with examples, many of which can be run by using the code supplied on the accompanying CD, this book is beneficial to statisticians and researchers involved in the above applications as well as quality-improvement experiments and missing-data analysis

关键词： analysis likelihood unified effects linear models random generalizedMathematics Science

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Systems Science and Mathematical Sciences 1997年第3期10卷 193-201页

作者： ZHU Zhongyi WEI Bocheng(Department of Mathematics, Southeast University, Nanjing 210096, China)

In this paper, a necessary condition for the existence of any weakly consistentestimator is presented in exponential family nonlinear models. Then we give one morenecessary condition for a consistent estimator in generalized linear models. Under mildregularity conditions, the existence, the strong consistency and the asymptotic normalityof MLE are proved in exponential family nonlinear models. Our results may be regardedas a further work of [1] in generalized linear models.

关键词： Exponential family nonlinear models consistency asymptotic normality maximum likelihood estimator Fisher information matrix.

COMPLETE　CONVERGENCE　OF　ERROR　VARIANCE　ESITIMATES　UNDER　Ф－MIXING　ERROR　IN　LINEAR　models

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Acta Mathematica Scientia 1994年第4期14卷 417-425页

作者：薛留根

In this paper,we consider the estimates d of error variance d2=Var(ei) in the linear models Yi=x' iβ+ei(i= 1, 2, ... ). We study the complete convergence of dm2-o2 when the error {ei }is a sequence of identically distributed p-mixing variables. And we also obtain the better convergence rates when {ei} is not identically distribution

关键词： ERROR LINEAR COMPLETE ESITIMATES CONVERGENCE MIXING models OF UNDER VARIANCE

TREE models IN THE COMBINATION OF SCIENTIFIC THEORIES WITH SPORTS PRACTIC

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北京体育大学学报 1996年第S2期19卷 63-65页

作者： CHI Jian(Beijing University of Physical Education)

The rapid development of sports suggests that scientific theories shoudld be the precursor in tapping the potentialities of physical function and in achieving good results in sports. Moreover, the social effect of science and technology can be realized only by applytng to sports training. Through analysis in this pa per,three models were suggested for thecombination for science and technology with sports, which may be used for future reference in sports practice.

关键词： models scientific theories sports practic

ON　THE　SMALLEST　POSSIBLE　ASYMPTOTICALLY　EFFICIENT　VARIANCE　IN　SEMIPARAMETRIC　models

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Systems Science and Mathematical Sciences 1994年第1期7卷 29-33页

作者： LIANG Hua(Institute Of Systems Science, Academia Sinica, Beliing 100080, China) 中科院系统科学所北京 100080

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ＯＮＴＨＥＳＭＡＬＬＥＳＴＰＯＳＳＩＢＬＥＡＳＹＭＰＴＯＴＩＣＡＬＬＹＥＦＦＩＣＩＥＮＴＶＡＲＩＡＮＣＥＩＮＳＥＭＩＰＡＲＡＭＥＴＲＩＣＭＯＤＥＬＳ￥ＬＩＡＮＧＨｕａ（ＩｎｓｔｉｔｕｔｅＯｆＳｙｓｔｅｍｓＳｃｉｅｎｃｅ，ＡｃａｄｅｍｉａＳｉｎｉｃａ，...

关键词： Semiparametric models the smallest possible asymptotically efficient variance.

Uncovering offline event similarity of online friends by constructing null models

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Chinese Physics B 2019年第6期28卷 486-494页

作者：崔文阔肖婧李婷许小可 College of Information and Communication Engineering Dalian Minzu UniversityDalian 116600China Guizhou Provincial Key Laboratory of Public Big Data Guizhou UniversityGuiyang 550025China

The emergence of Event-based Social Network(EBSN) data that contain both social and event information has cleared the way to study the social interactive relationship between the virtual interactions and physical interactions. In existing studies, it is not really clear which factors affect event similarity between online friends and the influence degree of each factor. In this study, a multi-layer network based on the Plancast service data is constructed. The the user’s events belongingness is shuffled by constructing two null models to detect offline event similarity between online friends. The results indicate that there is a strong correlation between online social proximity and offline event similarity. The micro-scale structures at multi-levels of the Plancast online social network are also maintained by constructing 0 k–3 k null models to study how the micro-scale characteristics of online networks affect the similarity of offline events. It is found that the assortativity pattern is a significant micro-scale characteristic to maintain offline event similarity. Finally, we study how structural diversity of online friends affects the offline event similarity. We find that the subgraph structure of common friends has no positive impact on event similarity while the number of common friends plays a key role, which is different from other studies. In addition, we discuss the randomness of different null models, which can measure the degree of information availability in privacy protection. Our study not only uncovers the factors that affect offline event similarity between friends but also presents a framework for understanding the pattern of human mobility.

关键词： event-based social networks(EBSNs) event similarity null models event chains