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THE CONVERGENCE OF A NEW MODIFIED BFGS METHOD WITHOUT LINE SEARCHES FOR UNCONSTRAINED OPTIMIZATION OR COMPLEXITY SYSTEMS

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Journal of Systems Science & Complexity 2010年第4期23卷 861-872页

作者： Liying LIU Zengxin WEI Xiaoping WU college of mathematics Science Liaocheng University Liaocheng 252059 China college of mathematics and information Science Guangxi University Nanning 530004 China School of Management Xi'an Jiaotong University Xi'an 710049 China

In this paper,a new modified BFGS method without line searches is *** traditionalBFGS method,this modified BFGS method is proposed based on the so-called fixed steplengthstrategy introduced by Sun and *** some suitable assumptions,the global convergence andthe superlinear convergence of the new algorithm are established,*** some preliminarynumerical experiments,which shows that the new Algorithm is feasible,is also reported.

关键词： BFGS method complexity systems global convergence superlinear convergence unconstrained optimization.

SINE TRANSFORM MATRIX FOR SOLVING TOEPLITZ MATRIX PROBLEMS

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Journal of Computational mathematics 2001年第2期19卷 167-176页

作者： Li-zhi Cheng (Department of mathematics & System sciences, National university of Defence Technology, Changsha 410073, china) 国防科技大学湖南长沙 410073

Provides information on a study which discussed the properties of eigenvalues for the solutions of symmetric positive definite Toeplitz systems, skew circulant and sine transform based properties. Eigenvalues of various preconditioners; Design of positive sine transform based preconditioners; Clustering property of the preconditioners; Numerical results.

关键词： preconditioner Toeplitz systems the fast sine transform conjugate gradient algorithm

UNIFORM ESTIMATE ON FINITE TIME RUIN PROBABILITIES WITH RANDOM INTEREST RATE

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Acta Mathematica Scientia 2010年第3期30卷 688-700页

作者：明瑞星何晓霞胡亦钧刘娟 School of mathematics and information sciences Jiangxi Normal University School of mathematics and Statistics Wuhan University college of Science Wuhan University of Science and Technology college of mathematics and Statistics Hubei Normal University

We consider a discrete time risk model in which the net payout （insurance risk） {Xk, k = 1, 2,...} are assumed to take real values and belong to the heavy-tailed class L∩ D and the discount factors （financial risk） {Yk, k = 1,2,...} concentrate on [θ, L], where 0 〈 0 〈 1, L 〈 ∞, {Xk, k = 1,2,...}, and {Yk, k=1,2,...} are assumed to be mutually independent. We investigate the asymptotic behavior of the ruin probability within a finite time horizon as the initial capital tends to infinity, and figure out that the convergence holds uniformly for all n ≥ 1, which is different from Tang Q H and Tsitsiashvili G （Adv Appl Prob, 2004, 36： 1278-1299）.

关键词： Random interest rate finite time ruin probability uniformity

Goodness-of-fit tests for vector autoregressive models in time series

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Science china mathematics 2010年第7期53卷 187-202页

作者： WU JianHong 1,& ZHU LiXing 21 college of Statistics and mathematics,Zhejiang Gongshang university,Hangzhou 310018,china 2 Department of mathematics,Hong Kong Baptist university,Hong Kong,china college of Statistics and mathematics Zhejiang Gongshang University Hangzhou China Department of mathematics Hong Kong Baptist University Hong Kong China

The paper proposes and studies some diagnostic tools for checking the goodness-of-fit of general parametric vector autoregressive models in time series. The resulted tests are asymptotically chi-squared under the null hypothesis and can detect the alternatives converging to the null at a parametric rate. The tests involve weight functions,which provides us with the flexibility to choose scores for enhancing power performance,especially under directional alternatives. When the alternatives are not directional,we construct asymptotically distribution-free maximin tests for a large class of alternatives. A possibility to construct score-based omnibus tests is discussed when the alternative is saturated. The power performance is also investigated. In addition,when the sample size is small,a nonparametric Monte Carlo test approach for dependent data is proposed to improve the performance of the tests. The algorithm is easy to implement. Simulation studies and real applications are carried out for illustration.

关键词： goodness-of-fit test maximin test nonparametric Monte Carlo test score type test time series vector autoregressive model

A NEWε-GENERALIZED PROJECTION METHOD OF STRONGLY SUB-FEASIBLE DIRECTIONS FOR INEQUALITY CONSTRAINED OPTIMIZATION

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Journal of Systems Science & Complexity 2011年第3期24卷 604-618页

作者： Jinbao JIAN Guodong MA Chuanhao GUO college of mathematics and information Science Guangxi University Nanning 530004 China Department of mathematics and Computer Science Yulin Normal University Yulin 537000 China college of Science Shanghai University Shanghai 200444 China.

In this paper, the nonlinear optimization problems with inequality constraints are discussed. Combining the ideas of the strongly sub-feasible directions method and the s-generalized projection technique, a new algorithm starting with an arbitrary initial iteration point for the discussed problems is presented. At each iteration, the search direction is generated by a new s-generalized projection explicit formula, and the step length is yielded by a new Armijo line search. Under some necessary assumptions, not only the algorithm possesses global and strong convergence, but also the iterative points always get into the feasible set after finite iterations. Finally, some preliminary numerical results are reported.

关键词： E-generalized projection global and strong convergence inequality constraints method of strongly sub-feasible directions optimization.

Community-based prevention and treatment of cardiovascular diseases

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Journal of Geriatric Cardiology 2024年第3期21卷 315-322页

作者： Sheng-Shou HU The Writing Committee of the Report on Cardiovascular Health and Diseases in china Fuwai Hospital National Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

The Annual Report on Cardiovascular Health and Diseases in china(2022)intricate landscape of cardiovascular health in *** is the third section of the report with a specific focus on community-based prevention and treatment of cardiovascular diseases(CVD).This section of the report underscores the importance of initiatives outlined in the"Healthy china 2030 Plan,"emphasizing the comprehensive prevention and control strategy for chronic diseases.A key aspect of this plan involves the establishment of national demonstration areas aimed at comprehensive prevention and control of chronic *** 2020,488 such areas had been set up across china,surpassing the initial target and covering a significant proportion of counties and *** report highlights the successful implementation of these strategies in Lishan district,Anshan city,where demonstration areas for comprehensive prevention and control of chronic diseases were launched in *** the course of seven years,the number of healthy units increased substantially,leading to improvements in managing risk factors for CVD among *** reductions in prevalence rates of overweight,obesity,smoking,passive smoking,and drinking were observed,along with the development of healthier behaviors among ***,Qiaokou district in Wuhan City,designated as a national demonstration area in 2014,implemented comprehensive public health promotion ***,special clinics for hypertension intervention were established,contributing to an increase in self-reported rates of hypertension,a slight decrease in prevalence,and a remarkable improvement in the control rate among treated ***,these efforts underscore the effectiveness of community-based approaches in driving positive health outcomes and advancing the comprehensive prevention and control of chronic diseases,particularly cardiovascular diseases,in china.

关键词： prevention district treatment

Research into a theoretical mode of coherent structures in the wall region of a turbulent boundary layer induced by a wall local disturbance

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Progress in Natural Science:Materials International 2009年第9期19卷 1119-1124页

作者： Changgen Lua,*, Qinjuan Qi b a college of Atmospheric sciences, Nanjing university of information Science & Technology, Nanjing 210044, china b college of Public Management, Nanjing university of information Science & Technology, Nanjing 210044, china college of Atmospheric sciences Nanjing University of Information Science & Technology Nanjing 210044 China college of Public Management Nanjing University of Information Science & Technology Nanjing 210044 China

The idea of applying direct numerical simulation (DNS), a theoretical mode of coherent structures in the wall region of a turbulent boundary layer, has been discussed in the literature. The various aspects of the formation mechanism of the coherent structures agree well with both DNS and experimental results. In addition, a close relationship has been found between the evolutional characteristics and factors such as the magnitude and structural distribution of the wall local impulse disturbance, and the amount of energy a local disturbance introduces into the wall region. Moreover, these parameters play key roles in the formation of coherent structures near the wall region of a turbulent boundary layer. Therefore, the wall local impulse disturbance provides a theoretical model for triggering the formation of coherent structures in the wall region of a turbulent boundary layer.

关键词： Turbulent boundary layer Wall region Coherent structure Local disturbance

Non-universal Gauge Bosons Z'and the Process e~+e~- →f

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Communications in Theoretical Physics 2004年第3期41卷 419-424页

作者： YUE Chong-Xing~1 WANG Shun-Zhi~2 1 Department of Physics,Liaoning Normal university,Dalian 116029,china 2 college of Physics and information Engineering,henan Normal university,Xinxiang 453002,china Department of Physics Liaoning Normal University Dalian 116029 college of Physics and information Engineering Henan Normal University Xinxiang 453002

Introduetion Altl、ough the standard model(SM)that bases on thega、lge gro、ip SU:(2)xU(1)has been sueeessful in de-seribing the Physies of eleetroweak interaetions,the meeh-anisn,of the eleetroweak symmetry breaking(... 详细信息

关键词： non-universal gauge bosons cross section TC2 models

Perfect reconstruction image modulation based on BEMD and quaternionic analytic signals

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Science china(information sciences) 2011年第12期54卷 2622-2634页

作者： QIAO LiHong 1 , NIU KaiFu 2 , WANG Ning 2 & PENG LiZhong 2 1 college of information Science and Engineering, henan university of Technology, Zhengzhou 450001, china 2 School of Mathematical sciences, Peking university, Beijing 100871, china college of information Science and Engineering Henan University of Technology Zhengzhou China School of Mathematical sciences Peking University Beijing China

Image modulation represents image by meaningful characters such as image instantaneous amplitude and instantaneous frequency. A perfect reconstruction image modulation method is proposed. In detail, the bidimensional empirical mode decomposition (BEMD) is first improved to adaptively decompose image into monocomponents. Then by the quaternionic analytic method, suitable analytic signals is acquired. A new polar form is further proposed to modulate images, then seven characters are derived including instantaneous amplitude and instantaneous frequencies. We demonstrate the techniques on both synthetic and natural images, depict the needle program of the estimated frequencies and obtain the reconstructions that are the same with the original images. The applications in image segmentation and separation establish the validity of characterizing images of this type as sums of locally narrow band modulated components.

关键词： perfect reconstruction image modulation AM-FM representation BEMD quaternionic analytic signals