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Empirical Likelihood Ratio Confidence Interval for Positively Associated Series

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Acta Mathematicae Applicatae Sinica 2007年第2期23卷 245-254页

作者： jun-jian Zhang College of Applied Sciences Beijing University of Technology Beijing 100022 China College of Mathematics Guangxi Normal University Guilin 541004 China

Empirical likelihood is discussed by using the blockwise technique for strongly stationary, positively associated random variables. Our results show that the statistics is asymptotically chi-square distributed and the... 详细信息

关键词： Empirical likelihood positive association blockwise confidence interval

Coupled 3D discrete-continuum numerical modeling of pile penetration in sand

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第1期13卷 44-55页

作者： jian ZHOU Qi-wei jian Jiao ZHANG jian-jun GUO Department of Geotechnical Engineering Tongji University Shanghai 200092 China School of Civil Engineering and Transportation Shanghai Technical College of Urban Management Shanghai 200432 China Sichuan Provincial Chuanjian Investigation and Design Institute Chengdu 610017 China

A coupled discrete-continuum simulation incorporating a 3D aspect and non-circular particles was performed to analyze soil-pile interactions during pile penetration in sand.A self-developed non-circular particle numerical simulation program was used which considered sand near the pile as interacted particles using a discrete element method;the sand away from the pile was simulated as a continuous medium exhibiting linear elastic *** domain analyzed was divided into two *** forces at the interface between the two zones were obtained from a discrete zone and applied to the continuum boundaries as nodal forces,while the interface velocities were obtained from the continuum zone and applied to the discrete *** show that the coupled discrete-continuum simulation can give a microscopic description of the pile penetration process without losing the discrete nature of the zone concerned,and may significantly improve computational efficiency.

关键词： Coupled numerical modeling Discrete-continuum Micro and macro 3D simulation Non-circular particles Pilepenetration mechanism

Higher order asymptotic behaviour of partial maxima of random sample from generalized Maxwell distribution under power normalization

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Applied Mathematics(A Journal of Chinese Universities) 2018年第2期33卷 177-187页

作者： HUANG jian-wen WANG jian-jun School of Mathematics and Statistics Southwest University Research Center for Artificial Intelligence & Education Big Data Southwest University

In this article, the higher order asymptotic expansions of cumulative distribution function and probability density function of extremes for generalized Maxwell distribution are established under nonlinear normalization. As corollaries, the convergence rates of the distribu- tion and density of maximum are obtained under nonlinear normalization.

关键词： higher order expansion extreme generalized Maxwell distribution nonlinear normalization

Unified Model for Generation Complex Networks with Utility Preferential Attachment

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Communications in Theoretical Physics 2006年第1X期46卷 183-186页

作者： WU jian-jun State Key Loboratory of Rail Traffic Control and Safety Beijing Jiaotong University Beijing 100044 China School of Traffic and Transportation Beijing Jiaotong University Beijing 100044 China

In this paper, based on the utility preferential attachment, we propose a new unified model to generate different network topologies such as scale-free, small-world and random networks. Moreover, a new network structure named super scale network is found, which has monopoly characteristic in our simulation experiments. Finally, the characteristics of this new network are given.

关键词： generation complex networks utility preferential attachment

Synthesis of a novel diether–ester conjugated model compound for electron donors of the polypropylene catalysts

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Chinese Chemical Letters 2013年第12期24卷 1106-1108页

作者： jian-jun Hu Beijing Research Institute of Chemical Industry SINOPEC

A novel diether-ester conjugated electron donor model compound, 1,3-dimethoxypropan-2-yl benzoate, was synthesized via a reaction of 1,3-dimethoxypropan-2-ol and benzoyl chloride in the presence of triethyl amine and 4-dimethylaminopryidine. Compared to the known routes of preparing diethers, which usually employ the reactions to O-alkylate the corresponding diols with O-alkylating reagents, the presented method here provides a new way to prepare the diether electron donor compounds. It avoids employing the traditional O-alkylation reactions, so that highly toxic O-alkylating chemicals, such as iodomethane, and very strong basic deprotonating reagents, such as alkoxides or metal hydrides, are not required. The product can be obtained in high yields without complicated purification processes. Catalyst component containing the electron donor compound was prepared and used to catalyze propylene polymerization.

关键词： Ether Ester Electron donors Polypropylene catalyst

Interpretation of Chinese Expert Consensus on the Diagnosis and Management Strategy of Patients with Statin Intolerance: A guiding file for helping to lipid management for Chinese population

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Journal of Geriatric Cardiology 2024年第7期21卷 713-715页

作者： jian-jun LI Cardiometabolic Center National Center for Cardiovascular DiseaseChinese Academy of Medical ScienceFuwai HospitalBeijingChina

It is well-known that elevated low-density lipoprotein cholesterol(LDL-C)is a causal risk factor for atheroscler-otic cardiovascular disease(ASCVD),statins are cornerstone drugs for the cause-based treatment of ASCVD,which has created a new era for ASCVD ***,statin intolerance is not clinically uncommon,which there are several issues with confu-sion and ***,a file named Chinese Expert Consensus on the Diagnosis and Management Strategy of Pa-tients With Statin Intolerance,like a navigator,has recently been published written by a team of experts from the Cardiovascular Metabolic Medicine Professional Committee,Expert Committee of the National Center for Cardiovascular Diseases aiming to en-hance the standardized clinical application of statins and improve the prevention and clinical *** this article,author briefly summarized the key points of above consensus in order to helping to comprehending the content of the consensus sugges-tions.

关键词： Expert Strategy corners

Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-Lin Shen jian-jun He Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

Structural dynamic responses analysis applying differential quadrature method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第11期7卷 1831-1838页

作者： PU jun-ping ZHENG jian-jun College of Architecture and Civil Engineering Zhejiang University of Technology Hangzhou 310032 China

Unconditionally stable higher-order accurate time step integration algorithms based on the differential quadrature method (DQM) for second-order initial value problems were applied and the quadrature rules of DQM, computing of the weighting coefficients and choices of sampling grid points were discussed. Some numerical examples dealing with the heat transfer problem, the second-order differential equation of imposed vibration of linear single-degree-of-freedom systems and double-degree-of-freedom systems, the nonlinear move differential equation and a beam forced by a changing load were computed, respectively. The results indicated that the algorithm can produce highly accurate solutions with minimal time consumption, and that the system total energy can remain conservative in the numerical computation.

关键词： Differential quadrature method (DQM) Dynamic response analysis Conservation of energy

Integrated Modeling of Process–Microstructure–Property Relations in Friction Stir Additive Manufacturing

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Acta Metallurgica Sinica(English Letters) 2020年第1期33卷 75-87页

作者： Zhao Zhang Zhi-jun Tan jian-Yu Li Yu-Fei Zu jian-jun Sha State Key Laboratory of Structural Analysis for Industrial Equipment Department of Engineering MechanicsFaculty of Vehicle Engineering and MechanicsDalian University of TechnologyDalian 116024China School of Aeronautics and Astronautics Dalian University of TechnologyDalian 116024China

Friction stir additive manufacturing is a newly developed solid-state additive manufacturing *** material in the stirring zone can be re-stirred and reheated,and mechanical properties can be changed along the building *** integrated model is developed to investigate the internal relations of process,microstructure and mechanical *** heat source model is used to simulate the friction stir additive manufacturing process to obtain the temperature histories,which are used in the following microstructural *** Carlo method is used for simulation of recrystallization and grain *** evolution model is used for calculation of precipitate size *** property is then *** are used for validation of the predicted grains and *** indicate that the average grain sizes on diff erent layers depend on the temperature in stirring and re-stirring *** the increase in building height,average grain size is decreased and hardness is *** increase in layer thickness can lead to temperature decrease in reheating and re-stirring processes and then lead to the decrease in average grain size and increase of hardness in stir zone.

关键词： Additive manufacturing Friction stir welding Integrated model Precipitate Re-stirring Reheating