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Journal of Hydrodynamics 2021年第2期33卷 243-258页

作者： Feng Pan Li-zhong mu Ying He Chao-jie Wang Shi-xiong Zhou School of Energy and Power Engineering Dalian University of TechnologyDalian 116024China

A thermal-hydrodynamic coupling model is used to investigate the interplay between the wall temperature distribution and the bubble departure during the nucleate boiling *** boiling process is modeled as the combination of three subprocesses:the transient heat conduction process in the solid heater,the evaporation of the microlayer underneath the bubble,and the bubble dynamics in the two-phase bulk fluid *** moving bubble interface is captured by the volume of fluid method in the OpenFOAM *** proposed model is validated against the experimental results of the boiling process of the water on an Indium Tin Oxide *** predicted results agree well with related measurements in the *** the validation,the effects of the boiling heat flux on the bubble departure period are *** results show that the bubble departure period decreases with the increase of the applied heat *** heat flux will cause irregularity in the departure periods for successive bubbles due to the influence of the wake flow evoked by the rising ***,the influence of the bubble contact angle on the boiling heat-transfer performance is *** is confirmed that the bubble departure diameter increases with the increase of the contact angle,meanwhile,the average wall temperature decreases with the increase of the contact angle.

关键词： Nucleate boiling thermal-hydrodynamic coupling simulation microlayer evaporation contact angle wall temperature distribution

Electromagnetic form factors of Σ^(+) and Σ^(-) in the vector-meson dominance model

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Communications in Theoretical Physics 2021年第5期73卷 66-70页

作者： zhong-Yi Li Ju-jun Xie Institute of Modem Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 101408China School of Physics and Microelectronics Zhengzhou UniversityZhengzhouHenan 450001China

Based on the recent measurements of the e^(+)e^(-)→∑^(+)∑^(-)^(-)and e^(+)e^(-)→∑^(-)∑^(-)^(+)processes by the Beijing SpectrometerⅢ(BESⅢ)collaboration,the electromagnetic form factors of the hyperon Σ^(+) and Σ^(-) in the timelike region are investigated using the vector-meson dominance model,where the contributions of theρ,ω,and φ mesons are taken into *** model parameters are determined from the BESⅢexperimental data of the timelike effective form factors|G_(eff)|of the Σ^(+) and Σ^(-) baryons for center-of-mass energies from 2.3864 to 3.02 *** is found that we can provide quantitative descriptions of the available data using as few as one adjustable model *** then progress to an analysis of the electromagnetic form factors in the spacelike region and evaluate the spacelike form factors of the hyperons Σ^(+) and Σ^(-).The electromagnetic form factors obtained for the Σ^(+) and Σ^(-) baryons are comparable with those of other model calculations.

关键词： Electromagnetic form factors Vector-meson dominance Hyperon–antihyperon pair production

Bipolar transurethral enucleation of prostate versus photoselective vaporization for symptomatic benign prostatic hyperplasia （〉70 ml）

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Asian Journal of Andrology 2017年第5期19卷 608-612页

作者： Xiao-Nan mu Si-jun Wang Ji Chen Xun-Bo Jin zhong-Xian Huang Long-Yang Zhang Cadres Integrative Unit 1 Jinan Central Hospital Affiliated to Shandong University Jinan 250013 Shandong P. R. China Department of Urology Jinan Central Hospital Affiliated to Shandong University Jinan 250013 Shandong P. R. China Department of Minimally Invasive Urology Provincial Hospital affiliated to Shandong University Jinan 250021 Shandong P. R. China

We prospectively compared the safety and efficacy of bipolar transurethral enucleation of the prostate （TUEP） versus 160-W lithium triboride laser （LBO） photoselective vaporization of the prostate （PVP） for trea... 详细信息

关键词： benign prostatic hyperplasia

Ab Initio Studies on the Structure and Binding Interaction of M^+CO_2(M=Sc,Ti…Zn)

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Chemical Research in Chinese Universities 1998年第2期14卷 80-85页

作者： FAN Hong-jun zhong Shi-jun LIU Chun-Wan Fujian Institute of Research on the Structure of Matter Chinese Academy of SciencesState Key Laboratory of Structural ChemistryFuzhouFujian350002

The geometry and binding interaction of M+CO2 (M represents the firstrow transition metals) were studied using ab initio methods. In some cases the frequency calculations and basis set superposition error corrections were included. For all the complexes under the study, the linear structures were found to be the equilibrium structure. The distances of M+—O in R(M+—O) in which M has 4s electrons are obvious longer than those in which M has no 4s electrons, and from Sc to Zn the change trend is decreased, accompanied with some oscillation. The binding energy has an opposite change trend to that of the R(M+—O). Linear M+CO2 has the same spin as M+, while Tshape structures may have different spins. The static electronic interaction was found to be about 80% of the total binding energy.

关键词： Chargeinduced dipole interaction Binding energy Equilibrium structure Ab initio

A nonlocal Boussinesq equation:multiple-soliton solutions and symmetry analysis

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Chinese Physics B 2022年第5期31卷 83-87页

作者： Xi-zhong Liu jun Yu Institute of Nonlinear Science Shaoxing UniversityShaoxing 312000China

A nonlocal Boussinesq equation is deduced from the local one by using consistent correlated bang *** study various exact solutions of the nonlocal Boussinesq equation,it is converted into two local equations which contain the local Boussinesq *** the N-soliton solutions of the local Boussinesq equation,the N-soliton solutions of the nonlocal Boussinesq equation are obtained,among which the(N=2,3,4)-soliton solutions are analyzed with *** periodic and traveling solutions of the nonlocal Boussinesq equation are derived directly from the known solutions of the local Boussinesq *** reduction solutions of the nonlocal Boussinesq equation are also obtained by using the classical Lie symmetry method.

关键词： nonlocal Boussinesq equation N-soliton solution periodic waves symmetry reduction solutions

System Analysis on Supercritical CO_2 Power Cycle with Circulating Fluidized Bed Oxy-Coal Combustion

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Journal of Thermal Science 2019年第3期28卷 505-518页

作者： SHI Yan zhong Wenqi SHAO Yingjuan XIANG jun Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and Environment Southeast University State Key Laboratory of Coal Combustion School of Energy and Power Engineering Huazhong University of Science and Technology

Supercritical carbon dioxide(S-CO_2) Brayton power cycle is a competitive technology to achieve high efficiency in a variety of applications. However, in coal power applications, the CO_2 generated from coal combustion still discharges into the atmosphere causing a series of environment problems. In this work, an 300 MWe S-CO_2 power cycle with circulating fluidized bed(CFB) oxy-coal combustion was established including air separation unit(ASU), CFB boiler, recuperator system and carbon dioxide compression and purification unit(CPU). Based on the material and energy conservation, the cycle efficiency of S-CO_2(620°C, 25 MPa) Brayton power cycle with CFB oxy-coal combustion is evaluated compared to the oxy-coal combustion steam Rankine cycle and S-CO_2 Brayton power cycle with the 31.65 kg/s coal supply. After that, the influence of several factors, e.g., exhaust flue gas temperature, split ratio in recuperator system and the oxygen supply on the cycle efficiency was investigated and analyzed. The results show that the net efficiency of S-CO_2 power cycle with CFB oxy-coal combustion(32.67%) is much higher than the steam Rankine cycle utilizing CFB with 17.5 Mpa, 540°C steam(27.3%), and 25 Mpa, 620°C steam(30.15%) under the same exhaust flue gas temperature. In addition, lower exhaust flue gas temperature and higher split ratio are preferred to achieve higher cycle efficiency. Lower oxygen supply can reduce the energy consumption of ASU and CPU, further increasing the system net efficiency. However, the energy losses of ASU and CPU are still very large in oxy-coal combustion and need to be improved in further work.

关键词： S-CO2 oxy-coal combustion CO2 capture CFB boiler process simulation

An anchor-based spectral clustering method

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Frontiers of Information Technology & Electronic Engineering 2018年第11期19卷 1385-1396页

作者： Qin ZHANG Guo-qiang zhong jun-yu DONG Department of Computer Science and Technology Ocean University of China Science and Information College Qingdao Agricultural University

Spectral clustering is one of the most popular and important clustering methods in pattern recognition,machine learning, and data mining. However, its high computational complexity limits it in applications involving truly large-scale datasets. For a clustering problem with n samples, it needs to compute the eigenvectors of the graph Laplacian with O(n^3) time complexity. To address this problem, we propose a novel method called anchor-based spectral clustering(ASC) by employing anchor points of data. Specifically, m(m≤n) anchor points are selected from the dataset, which can basically maintain the intrinsic(manifold) structure of the original data. Then a mapping matrix between the original data and the anchors is constructed. More importantly, it is proved that this data-anchor mapping matrix essentially preserves the clustering structure of the data. Based on this mapping matrix, it is easy to approximate the spectral embedding of the original data. The proposed method scales linearly relative to the size of the data but with low degradation of the clustering performance. The proposed method, ASC,is compared to the classical spectral clustering and two state-of-the-art accelerating methods, i.e., power iteration clustering and landmark-based spectral clustering, on 10 real-world applications under three evaluation *** results show that ASC is consistently faster than the classical spectral clustering with comparable clustering performance, and at least comparable with or better than the state-of-the-art methods on both effectiveness and efficiency.

关键词： Clustering Spectral clustering Graph Laplacian Anchors

A multi-phase Field Model for Static Recrystallization of Hot Deformed Austenite in a C–Mn Steel

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Acta Metallurgica Sinica(English Letters) 2018年第2期31卷 208-215页

作者： jun Zhang Cheng-Wu Zheng Dian-zhong Li School of Chemistry and Materials Science University of Science and Technology of China Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences

A multi-phase-field model has been developed to simulate the microstructure evolution and kinetics of the austenite static recrystallization（SRX） in a C–Mn steel. In this model, the bulk free energy that coupling the deformation stored energy with a special interpolation function is incorporated. Both the deformed grain topology and the deformation stored energy have been included in order to investigate the influence of pre-deformation on the subsequent austenite SRX at different hot deformation levels. Diverse scenarios of microstructure evolution show different deformation-dependent recrystallized grain sizes. The transformation kinetics is then discussed by analyzing the overall SRX fraction and the average interface velocity on the recrystallization front.

关键词： Phase-field Static recrystallization Microstructure evolution Hot deformation Mesoscopic modeling

Approach for earth observation satellite real-time and playback data transmission scheduling

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Journal of Systems Engineering and Electronics 2015年第5期26卷 982-992页

作者： Hao Chen Longmei Li Zhinong zhong jun Li School of Electronics Science and Engineering National University of Defense Technology

The scheduling of earth observation satellites(EOSs)data transmission is a complex combinatorial optimization problem. Current researches mainly deal with this problem on the assumption that the data transmission mode is fixed, either playback or real-time transmission. Considering the characteristic of the problem, a multi-satellite real-time and playback data transmission scheduling model is established and a novel algorithm based on quantum discrete particle swarm optimization(QDPSO)is proposed. Furthermore, we design the longest compatible transmission chain mutation operator to enhance the performance of the algorithm. Finally, some experiments are implemented to validate correctness and practicability of the proposed algorithm.

关键词： multi-satellite data transmission scheduling satellite data transmission mode decision particle swarm optimization mutation operator

Linear random search and engineering estimation of sinkage for launching carrier aircraft

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Science China(Technological Sciences) 2019年第6期62卷 996-1002页

作者： zhong Guo HUANG jun ZHOU ZeYang YI MingXu School of Aeronautic Science and Engineering Beijing University of Aeronautics and Astronautics

A linear random search algorithm(LRSA) is developed to determine the critical value of takeoff weight limited to the safe flight track sinkage and an engineering estimation method(EEM) is proposed to calculate the sinkage of carrier aircraft launch in real time. Based on the analysis of free flight after leaving the carrier, the equations are established to participate into engineering estimation of flight track sinkage. Thanks to the proposed search algorithm, the maximum takeoff weight of carrier aircraft with safe catapult launch flight track sinkage is generated in few steps. The results of sinkage estimation and the search algorithm are in good agreement with that of aircraft catapult launch simulation. The main contribution of this manuscript is the establishment of simple and accurate engineering estimation for carrier aircraft launch flight track sinkage and the development of robust and efficient search algorithm for the critical value with safe catapult criteria.

关键词： carrier aircraft launch flight track sinkage engineering estimation linear random search simulation