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Calculation of microscopic nuclear level densities based on covariant density functional theory

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Nuclear Science and Techniques 2023年第9期34卷 118-127页

作者： Kun-peng Geng peng-xiang Du Jian Li Dong-Liang Fang College of Physics Jilin UniversityChangchun 130012China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China

In this study,a microscopic method for calculating the nuclear level density(NLD)based on the covariant density functional theory(CDFT)is *** particle-hole state density is calculated by a combinatorial method using single-particle level schemes obtained from the CDFT,and the level densities are then obtained by considering collective effects such as vibration and *** results are compared with those of other NLD models,including phenomenological,microstatisti-cal and nonrelativistic Hartree–Fock–Bogoliubov combinatorial *** comparison suggests that the general trends among these models are essentially the same,except for some deviations among the different NLD *** addition,the NLDs obtained using the CDFT combinatorial method with normalization are compared with experimental data,including the observed cumulative number of levels at low excitation energies and the measured *** CDFT combinatorial method yields results that are in reasonable agreement with the existing experimental data.

关键词： Nuclear level density Covariant density functional theory Combinatorial method

A Method to Construct the Nonlocal Symmetries of Nonlinear Evolution Equations

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Chinese Physics Letters 2013年第10期30卷 5-8页

作者： XIN xiang-peng CHEN Yong Shanghai Key Laboratory of Trustworthy Computing East China Normal UniversityShanghai 200062

A method is proposed to seek the nonlocal symmetries of nonlinear evolution *** validity and advantages of the proposed method are illustrated by the applications to the Boussinesq equation,the coupled Korteweg-de Vries system,the Kadomtsev–Petviashvili equation,the Ablowitz–Kaup–Newell–Segur equation and the potential Korteweg-de Vries *** facts show that this method can obtain not only the nonlocal symmetries but also the general Lie point symmetries of the given equations.

关键词： equations equation equation

Local multi-model integrated soft sensor based on just-in-time learning for mechanical properties of hot strip mill process

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Journal of Iron and Steel Research International 2021年第7期28卷 830-841页

作者： Jie Dong Ying-ze Tian Kai-xiang peng Key Laboratory of Knowledge Automation for Industrial Processes of Ministry of Education School of Automation and Electrical EngineeringUniversity of Science and Technology BeijingBeijing 100083China National Engineering Research Center for Advanced Rolling Technology University of Science and Technology BeijingBeijing 100083China

The mechanical properties of hot rolled strip are the key index of product quality,and the soft sensing of them is an important decision basis for the control and optimization of hot rolling *** solve the problem that it is difficult to measure the mechanical properties of hot rolled strip in time and accurately,a soft sensor based on ensemble local modeling was ***,outliers of process data are removed by local outlier *** standardization and transformation,normal data that can be used in the model are ***,in order to avoid redundant variables participating in modeling and reducing performance of models,feature selection was applied combing the mechanism of hot rolling process and mutual information among ***,features of samples were extracted by supervised local preserving projection,and a prediction model was constructed by Gaussian process regression based on just-in-time learning(JITL).Other JITL-based models,such as support vector regression and gradient boosting regression tree models,keep all variables and make up for the lost information during dimension ***,the soft sensor was developed by integrating individual models through stacking *** and reliability of proposed soft sensors were verified by actual process data from a real hot rolling process.

关键词： Soft sensor Just-in-time learning Multi-model Hot rolling

Strengthening-toughening methods and mechanisms of Mg-Li alloy:a review

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Rare Metals 2022年第4期41卷 1176-1188页

作者： xiang peng Wen-Cai Liu Guo-Hua Wu National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composite School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Magnesium-lithium(Mg-Li) alloy,as the lightest metal structure material,has unparalleled market prospects in aerospace,weapons and equipment,electronic technology,transportation,and many other ***,it is hard to balance the superlight and high strength of Mg-Li alloy,and the inferior high-temperature strength and poor high-temperature stability limit the wide application of Mg-Li *** present,the main methods to improve the mechanical properties of Mg-Li alloy are alloying,grain refinement,and compound *** domestic and overseas research progress in the strengthening and toughening methods and mechanisms of Mg-Li alloy are reviewed,and the future development of the high strength and high toughness Mg-Li alloy is prospected.

关键词： Mg-Li alloy Solution strengthening Precipitation strengthening Grain reflnement strengthening Compound strengthening

Precise Transceiver-Free Localization in Complex Indoor Environment

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China Communications 2016年第5期13卷 28-37页

作者： Rui Mao peng xiang Dian Zhang College of Computer Science and Software Shenzhen University

Transceiver-free object localization can localize target through using Radio Frequency(RF) technologies without carrying any device, which attracts many researchers' attentions. Most traditional technologies usually first deploy a number of reference nodes which are able to communicate with each other, then select only some wireless links, whose signals are affected the most by the transceiver-free target, to estimate the target position. However, such traditional technologies adopt an ideal model for the target, the other link information and environment interference behavior are not considered comprehensively. In order to overcome this drawback, we propose a method which is able to precisely estimate the transceiver-free target position. It not only can leverage more link information, but also take environmental interference into account. Two algorithms are proposed in our system, one is Best K-Nearest Neighbor(KNN) algorithm, the other is Support Vector Regression(SVR) algorithm. Our experiments are based on Telos B sensor nodes and performed in different complex lab areas which have many different furniture and equipment. The experiment results show that the average localization error is round 1.1m. Compared with traditional methods, the localization accuracy is increased nearly two times.

关键词： indoor localization transceiver-free radio map support vector regression

Personalized image-based templates for precise acetabular prosthesis placement in total hip arthroplasty:a pilot study

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第9期11卷 673-680页

作者： Bin CHEN Sheng-xiang XIAO peng-cheng GU xiang-jin LIN Department of Orthopaedics the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective：In order to achieve accurate implantation of the acetabular prosthesis in total hip arthroplasty（THA）,we designed individual templates based on a three-dimensional（3D） model generated from computed tomography（CT） ***：Individual templates were designed for 12 patients who underwent THA.A physical template was designed to conform to the contours of the patient＇s acetabulum and to confirm the rotation of the acetabular *** guided the acetabular component ***：The preoperative and postoperative X-ray and CT scans were obtained to assess the location with respect to the accuracy of the acetabular *** all patients,the abduction angle of the acetabular component was 46.7°to 54.3°and the anteversion angle was 11.3°to 18.5°Conclusions：The assessment of postoperative CT scans demonstrated higher accuracy of the acetabular component bore when used with the individual ***,the individual template can be an alternative to the computer-assisted navigation systems,with a good cost-performance ratio.

关键词： Total hip arthroplasty Templates Acetabular prosthesis

Saturation throughput analysis of RTS/CTS scheme in an error-prone WLAN channel

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第12期10卷 1714-1719页

作者： xiang-yu peng Le-tian JIANG Guo-zhi XU Department of Electronic Engineering Shanghai Jiao Tong University Shanghai 200240 China

In this paper, a new three-dimensional Markov model is proposed for the estimation of saturation throughput of RTS/CTS (request to send/clear to send) scheme in an error-prone wireless local area network (WLAN) channel. The model takes account of the effect of bit error on all the frames, and station short and long retry limits. Saturation throughput was re-analyzed using the new Markov model and numerical results closely matched those from simulation, confirming the accuracy of the new model. Evaluation of the influence of different parameters on throughput showed that the saturation throughput is sensitive to channel bit error rates and packet length, especially in high bit error conditions.

关键词： Saturation throughput RTS/CTS Error-prone WLAN channel Markov model _ _

On the comparison of particle regeneration technique and volume adaptive scheme in the compressible flow based on smoothed particle hydrodynamics

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Journal of Hydrodynamics 2022年第3期34卷 408-421页

作者： Ming-Kang Li Shuai Zhang Yu-xiang peng A-Man Zhang College of Shipbuilding Engineering Harbin Engineering UniversityHarbin150001China Nanhai Institute of Harbin Engineering University Sanya572024China School of Marine Engineering and Technology Sun Yat-sen UniversityZhuhai519082China

The collapse of a cavitation bubble is an interesting topic and it has many applications in the engineering *** to its compressible nature,the modelling of a cavitation bubble is not easy by the Lagrangian method,like the smoothed particle hydrodynamics(SPH),as there is large variation of particle ***,there are two kinds of method that have been proposed to deal with this problem:the particle regeneration technique(PRT)and the volume adaptive scheme(VAS).They have all been validated via several numerical tests of compressible flow in the past *** is based on totally different concept,the ultimate simulation results and properties may ***,we intend to compare these two methods based on the Riemann-based SPH solver with monotone upwind-centered scheme for conservation laws(MUSCL)reconstruction via several numerical *** characteristics of these two methods are discussed and the applicable scope for them are also commented for further usage.

关键词： Compressible flow smoothed particle hydrodynamics(SPH) particle regeneration technique(PRT) volume adaptive scheme(VAS)

Pseudo-dynamic tests on masonry residential buildings seismically retrofitted by precast steel reinforced concrete walls

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Earthquake Engineering and Engineering Vibration 2017年第3期16卷 587-597页

作者： Li Wenfeng Wang Tao Chen Xi Zhong xiang Pan peng Beijing Institute of Architectural Design Beijing 100045 China Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake Administration Sanhe 065201 China Department of Civil Engineering Tsinghua University Beijing 100084 China

A retrofitting technology using precast steel reinforced concrete（PSRC） panels is developed to improve the seismic performance of old masonry buildings. The PSRC panels are built up as an external PSRC wall system surrounding the existing masonry building. The PSRC walls are well connected to the existing masonry building, which provides enough confinement to effectively improve the ductility, strength, and stiffenss of old masonry structures. The PSRC panels are prefabricated in a factory, significantly reducing the situ work and associated construction time. To demonstrate the feasibility and mechanical effectivenss of the proposed retrofitting system, a full-scale five-story specimen was constructed. The retrofitting process was completed within five weeks with very limited indoor operation. The specimen was then tested in the lateral direction, which could potentially suffer sigifnicant damage in a large earthquake. The technical feasibility, construction workability, and seismic performance were thoroughly demonstrated by a full-scale specimen construction and pseudo-dynamic tests.

关键词： masonry buildings precast SRC panel seismic retrofit pseudo-dynamic test seismic performance