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Weighted Estimates for a Class of Global Maximal Operators Associated with Dispersive Equation

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Acta Mathematicae Applicatae Sinica 2022年第1期38卷 187-208页

作者： Yong DING Yao-ming niu School of Mathematical Sciences Beijing Normal UniversityLaboratory of Mathematics and Complex Systems(BNU)Ministry of EducationBeijing 100875China Faculty of Mathematics Baotou Teachers’College of Inner Mongolia University of Science and TechnologyBaotou 014030China

For a function Ф satisfying some suitable growth conditions,consider the following general dispersive equation defined by{i■tu+Ф(√-△)u=0,u(x,0)=f(x),(x,t)∈R^(n)× R,f∈S(R^(n) where Ф(√-△)is a pseudo-differential operator with symbol Ф(|ξ|).In the present paper,when the initial data f belongs to Sobolev space,we give the local and global weighted L^(q) estimate for the global maximal operator S^(**)Ф defined by S^(**)Фf(x)=sup_(t∈R)|S_(t,Ф)f(x)|,where S_(t,Ф)f(x)=(2π)^(-n)∫_(R^(n)e^(ix·ζ+itФ(|ζ+|)f(ζ)dζ is a formal solution of the equation(*).

关键词： global maximal operator weighted estimate pseudo-differential operator dispersive equation

Prediction of nuclear charge density distribution with feedback neural network

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Nuclear Science and Techniques 2022年第12期33卷 24-35页

作者： Tian‑Shuai Shang Jian Li Zhong‑ming niu College of Physics Jilin UniversityChangchun 130012China School of Physics and Optoelectronic Engineering Anhui UniversityHefei 230601China

Nuclear charge density distribution plays an important role in both nuclear and atomic physics,for which the two-parameter Fermi(2pF)model has been widely applied as one of the most frequently used ***,the feedforward neural network has been employed to study the available 2pF model parameters for 86 nuclei,and the accuracy and precision of the parameter-learning effect are improved by introducing A^(1∕3)into the input parameter of the neural ***,the average result of multiple predictions is more reliable than the best result of a single prediction and there is no significant difference between the average result of the density and parameter values for the average charge density *** addition,the 2pF parameters of 284(near)stable nuclei are predicted in this study,which provides a reference for the experiment.

关键词： Charge density distribution Two-parameter Fermi model Feedforward neural network approach

A review on applications of heuristic optimization algorithms for optimal power flow in modern power systems

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Journal of Modern Power Systems and Clean Energy 2014年第4期2卷 289-297页

作者： ming niu Can WAN Zhao XU The Hong Kong Polytechnic University Hong KongChina

Optimal power flow(OPF)is one of the key tools for optimal operation and planning of modern power *** to the high complexity with continuous and discrete control variables,modern heuristic optimization algorithms(HOAs)have been widely employed for the solution of *** paper provides an overview of the latest applications of advanced HOAs in OPF *** most frequently applied HOAs for solving the OPF problem in recent years are covered and briefly introduced,including genetic algorithm(GA),differential evolution(DE),particle swarm optimization(PSO),and evolutionary programming(EP),etc.

关键词： Heuristic optimization algorithm Optimal power flow Multi-objective optimization Constraint optimization

Boundedness for Parabolic Singular Integral with Rough Kernels and Its Commutators on Triebel-Lizorkin Spaces

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Acta Mathematica Sinica,English Series 2011年第9期27卷 1783-1802页

作者： Shuang Ping TAO Yao ming niu College of Mathematics and Information Science Northwest Normal University Lanzhou 730070 P. R. China Faculty of Mathematics Baotou Teachers College Baotou 014030 P. R. China

In this paper, the authors give the boundedness on Triebel-Lizorkin spaces for the parabolic singular integral with rough kernel and its commutator.

关键词： Parabolic singular integral Triebel-Lizorkin spaces commutator parabolic BMO

Influence of the Coulomb exchange term on nuclear single-proton resonances

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Nuclear Science and Techniques 2016年第5期27卷 231-237页

作者： Shu-Yang Wang Zhong-Lai Zhu Zhong-ming niu School of Physics and Materials Science Anhui University

Nuclear single-proton resonances are sensitive to the Coulomb field,while the exchange term of Coulomb field is usually neglected due to its *** combining the complex scaling method with the relativistic mean-field model,the influence of the Coulomb exchange term on the single-proton resonances is investigated by taking Sn isotopes and N=82 isotones as *** is found that the Coulomb exchange term reduces the singleproton resonance energy within the range of 0.4-0.6 MeV and leads to similar isotopic and isotonic trends of the resonance energy as those without the Coulomb exchange ***,the single-proton resonance width is also reduced by the Coulomb exchange term,whose influence generally decreases with the increasing neutron number and increases with the increasing proton ***,the influence of the Coulomb exchange term cannot change the trend of the resonance width with respect to the neutron number and proton ***,the influence of the Coulomb exchange term on the resonance width is investigated for the doubly magic nuclei ^(40)Ca,^(56,78)Ni,^(100,132)Sn,and ^(208)*** is found that the Coulomb exchange term reduces the proton resonance width within 0.2 MeV,whose magnitude depends on the specific nucleus and the quantum numbers of resonant states.

关键词：共振能量库仑场交换项质子数相对论平均场模型共振宽度中子数非定域性

Therapeutic effect of two methods on avulsion fracture of tibial insertion of anterior cruciate ligament

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World Journal of Clinical Cases 2022年第27期10卷 9641-9649页

作者： Hai-ming niu Qing-Chun Wang Rui-Zhao Sun Department of Orthopedics Guanyun People's HospitalLianyungang 222200Jiangsu ProvinceChina

BACKGROUND The tibial stop of anterior cruciate ligament(ACL) is fan-shaped and attached to the medial groove in front of the intercondylar spine,which is located between the anterior horn of the medial and lateral *** incidence of this fracture is low previously reported,which is common in children and *** the increase of sports injury and traffic injury and the deepening of understanding,it is found that the incidence of the disease is high at *** To explore the difference between open reduction and internal fixation with small incision and high-intensity non-absorbable suture under arthroscopy in the treatment of tibial avulsion fracture of *** Seventy-six patients with tibial avulsion fracture of anterior cruciate ligament diagnosed and treated in Guanyun County People’s Hospital from April 2018 to June 2020 were retrospectively *** to the surgical methods,they were divided into group A(40 cases) and group B(36 cases).Patients in group A were treated with arthroscopic high-strength non-absorbable suture,and patients in group B were treated with small incision open reduction and internal *** operation time,fracture healing time,knee joint activity and functional score before and after operation,and surgical complications of the two groups were *** The operation time of group A was higher than that of group B,and the difference was statistically significant(P 0.05);The knee joint function activity was compared between two groups before operation,3 mo and 6 mo after operation,and the difference was not statistically significant(P > 0.05);the knee joint function activity of group A and group B at 3 mo and 6 mo after operation was significantly higher than that before operation(P < 0.05);the limp,support,lock,instability,swelling,upstairs,squatting,pain and Ly

关键词： Small incision Anterior cruciate ligament Open reduction and internal fixation Arthroscopy Non-absorbable sutures Anterior cruciate ligament tibial avulsion fracture

Mass predictions of the relativistic continuum Hartree-Bogoliubov model with radial basis function approach

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Chinese Physics C 2019年第7期43卷 53-60页

作者： Min Shi Zhong-ming niu Hao-Zhao Liang School of Mathematics and Physics Anhui Jianzhu UniversityHefei 230601China School of Physics and Materials Science Anhui UniversityHefei 230601China Institute of Physical Science and Information Technology Anhui UniversityHefei 230601China RIKEN Nishina Center Wako 351-0198Japan Department of Physics Graduate School of ScienceThe University of TokyoTokyo 113-0033Japan

The radial basis function(RBF) approach is a powerful tool to improve nuclear mass predictions. By combining the RBF approach with the latest relativistic continuum Hartree-Bogoliubov(RCHB) model, the local systematic deviations between the RCHB mass predictions and the experimental data are eliminated, and the root-meansquare(rms) mass deviation is significantly reduced from 7.923 MeV to 0.386 MeV. However, systematic deviations between the RBF improved mass predictions and the experimental data remain for nuclei with four different odd-even parities, i.e.(even Z, even N),(even Z, odd N),(odd Z, even N), and(odd Z, odd N). They can be reduced by separately training RBF for the four groups of nuclei, and the resulting rms deviation decreases to 0.229 MeV. It is found that the RBF approach can describe the deformation effects neglected in the present RCHB mass calculations, and also improves the description of the shell effect and the pairing effect.

关键词： nuclear masses radial basis function approach relativistic continuum Hartree-Bogoliubov model

Advances of machining techniques for gradient structures in multi-principal-element alloys

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Rare Metals 2022年第12期41卷 4015-4026页

作者： Bo Li Chun-ming niu Tian-Long Zhang Gong-Yu Chen Gang Zhang Dong Wang Xiao-Ye Zhou Jia-ming Zhu School of Civil Engineering Shandong UniversityJinan 250061China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Department of Materials Science and Engineering College of Science and EngineeringHong Kong Institute for Advanced StudyCity University of Hong KongHong Kong 999077China School of Physics and Optoelectronics Technology Baoji University of Arts and SciencesBaoji 721016China Center of Microstructure Science Frontier Institute of Science and TechnologyXi'an Jiaotong UniversityXi’an 710049China Guangdong Province Key Laboratory of Durability for Marine Civil Engineering School of Civil and Transportation EngineeringShenzhen UniversityShenzhen 518060China

Multi-principal-element alloys(MPEAs)are attracting increasing attentions because of their high strength and ductility,high fracture toughness,excellent corrosion resistance,outstanding thermal-softening resistance and high oxidation ***,gradient structures(GSs)have been shown to be effective in alleviating the strength-ductility trade-off although strength and ductility are mutually exclusive properties for metals,which provides an opportunity for developing highperformance ***,we summarized four processing methods for creating GSs in MPEAs,including rotationally accelerated shot peening(RASP),ultra-precision machining technology(UPMT),cyclic dynamic torsion(CDT),and ultrasonic surface rolling processing(USRP).Principles,advantages,disadvantages,and typical applications of these methods are discussed in this work.

关键词： Gradient structures(GSs) Multi-principalelement alloys(MPEAs) Strength-ductility trade-off Advanced processing technology

Synthesis and Properties of Poly(aryl ether ketone) Copolymers Containing 2,7-Naphthalene Moieties

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Chemical Research in Chinese Universities 2006年第1期22卷 114-117页

作者： LIU Si-jie niu Ya-ming ZHU Xiao-liang WANG Gui-bin JIANG Zhen-hua Alan G. MacDiarmid Institute College of Chemistry Jilin University Changchun 130012 P.R. China

Poly（ aryl ether ketone） copolymers containing 2,7-naphthylene and hydroquinone（HQ） moieties with various compositions were prepared by the reaction of 4,4＇-difluorobenzophenone（DFB） 2,7-naphthylene and hydroquinone in the presence of sodium carbonate and potassium carbonate （ 19： 1, mass ratio） in diphenyl sulfone （DPS）. The thermal analysis results of the copolymers show that the glass transition temperatures（Tgs） increase, while the melting temperatures（Tra） and tile 5.0% weight loss temperatures （ Td ） decrease with the increase of the 2,7-naphthalene moieties. For the copolymers synthesized at a molar fraction of 2,7-naphthalene in the difluoro monomers being over 0.30, no peaks corresponding to the cold crystallization temperature and the melting temperature could be detected, indicating that these copolymers are almost amorphous. The crystal structures of the copolymers with a molar fraction of 2,7-naphthalene being less than 0. 30 are rhombic.

关键词： Poly( aryl ether ketone) Naphthalene derivatives Friedel-crafts acylation