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Approximate Customized Proximal Point Algorithms for Separable Convex Optimization

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Journal of the Operations Research Society of China 2023年第2期11卷 383-408页

作者： hong-mei chen Xing-Ju Cai Ling-Ling Xu School of Mathematical Sciences Nanjing Normal UniversityNanjing 210023JiangsuChina Jiangsu Key Laboratory for NSLSCS Nanjing Normal UniversityNanjing 210023JiangsuChina

Proximal point algorithm(PPA)is a useful algorithm framework and has good convergence *** difficulty is that the subproblems usually only have iterative *** this paper,we propose an inexact customized PPA framework for twoblock separable convex optimization problem with linear *** design two types of inexact error criteria for the *** first one is absolutely summable error criterion,under which both subproblems can be solved *** one of the two subproblems is easily solved,we propose another novel error criterion which is easier to implement,namely relative error *** relative error criterion only involves one parameter,which is more *** establish the global convergence and sub-linear convergence rate in ergodic sense for the proposed *** numerical experiments on LASSO regression problems and total variation-based image denoising problem illustrate that our new algorithms outperform the corresponding exact algorithms.

关键词： Inexact criteria Proximal point algorithm Alternating direction method of multipliers Separable convex programming

Investigation of contemporary college students’mental health status and construction of a risk prediction model

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World Journal of Psychiatry 2023年第8期13卷 573-582页

作者： Xiao-Li Mao hong-mei chen School of Health and Nursing Wuchang University of TechnologyWuhan 430223Hubei ProvinceChina

BACKGROUND Due to academic pressure,social relations,and the change of adapting to independent life,college students are under high levels of ***,it is very important to study the mental health problems of college *** a predictive model that can detect early warning signals of college students’mental health risks can help support early intervention and improve overall *** To investigate college students’present psychological well-being,identify the contributing factors to its decline,and construct a predictive nomogram *** We analyzed the psychological health status of 40874 university students in selected universities in Hubei Province,China from March 1 to 15,2022,using online questionnaires and random *** influencing their mental health were also analyzed using the logistic regression approach,and R4.2.3 software was employed to develop a nomogram model for risk *** We randomly selected 918 valid data and found that 11.3%of college students had psychological *** results of the general data survey showed that the mental health problems of doctoral students were more prominent than those of junior college students,and the mental health of students from rural areas was more likely to be abnormal than that of urban *** addition,students who had experienced significant life events and divorced parents were more likely to have an abnormal *** abnormal group exhibited significantly higher Patient Health Questionnaire-9(PHQ-9)and Generalized Anxiety Disorder-7 scores than the healthy group,with these differences being statistically significant(P<0.05).The nomogram prediction model drawn by multivariate analysis includ-ed six predictors:The place of origin,whether they were single children,whether there were significant life events,parents’marital status,regular exercise,intimate friends,and the PHQ-9 *** training set demonstrated an area under the receiver operat

关键词： College Predictive models Psychological health Risk factors Logistic regression analysis Influencing factors

Improvement of Mechanical Properties of Magnesium Alloy ZK60 by Asymmetric Reduction Rolling

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Acta Metallurgica Sinica(English Letters) 2018年第1期31卷 63-70页

作者： Ling Wang Yi-Quan Zhao hong-mei chen Jing Zhang Yan-Dong Liu Yi-Nong Wang School of Materials Science and Engineering Northeastern University Shenyang 110819 China Yingkou Institute of Technology Yingkou 115014 China School of Materials Science and Engineering Dalian University of Technology Dalian 116024 China Provincial Key Lab of Advanced Welding Technology Jiangsu University of Science and Technology Zhenjiang 212003 China School of Metallurgy and Materials Engineering Jiangsu University of Science and Technology Zhangjiagang 215600 China

The improvement of mechanical properties of ZK60 processed by asymmetric reduction rolling （ARR） was investigated in this paper. The grain refinement and basal texture intensity decrease were attributed to the introduction of shear stress produced by ARR process. Compared to conventional symmetrical rolled （SR） ZK60 alloys, ARRed ZK60 exhibited finer, more homogeneous grains and higher mechanical properties. The intensity of basal texture of ARRed ZK60 after annealing was lower than that of SRed ZK60 after annealing. ZK60 sheet with good combination of strength and ductility could be obtained by ARR process. The yield strength （YS） and ultimate tensile strength （UTS） of the ARRed ZK60 sheet were increased 150% and 91.3%, compared to those of SRed ZK60 sheet, from 80 to 200 MPa and from 140 to 264 MPa, respectively. Simultaneously, the elongation to failure increased by 68.75% in the ARR sheet （27%） when compared to that of the SR sheet （16%）.

关键词： ZK60 ARR Microstructure Texture Mechanical properties

Effect of extrusion temperature on microstructure and tensile properties of Mg-Gd-Er-Zn-Zr alloy containing LPSO phase

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Journal of Iron and Steel Research International 2023年第8期30卷 1633-1641页

作者： Si-shu Wang Qian-hao Zang hong-mei chen Yu-hang Guo Feng-jian Shi Di Feng School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003JiangsuChina Foshan(Southern China)Institute for New Materials Foshan 528247GuangdongChina

The Mg-1Gd-0.75Er-0.5Zn-0.18Zr(at.%)alloy with long-period stacking ordered(LPSO)phase was prepared by metal mold casting and hot *** extruded samples had a typical bimodal *** different fractions of equiaxed grains were observed in annealed *** percentage of fine grains decreased in the extruded Mg alloys with and without annealing treatment when the extrusion temperature was *** LPSO phases promote recrystal-lization behavior in the samples through particle-stimulated nucleation(PSN)*** Mg alloys extruded at 300℃ with or without annealing treatment obtained the best tensile *** the low extrusion temperature,more finely equiaxed grains with random texture are formed through PSN,and more LPSO phase kink bands are formed,which could improve the mechanical properties of the extruded Mg alloys.

关键词： Mg alloy LPSO phase Recrystallization Texture Tensile property

Thermoelectric properties of Al substituted misfit cobaltite Ca_3(Co_(1-x)Al_x)_4O_9 at low temperature

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International Journal of Minerals,Metallurgy and Materials 2014年第7期21卷 720-725页

作者： Yi Liu hong-mei chen Jin-lian Hu Xu-bing Tang Hai-jin Li Wei Wang School of Mathematics and Physics Anhui University of Technology Institute of Optoelectronic Information Materials and Technologies Anhui University of Technology School of Materials Science & Engineering Anhui University of Technology

Thermoelectric properties of Al substituted compounds Ca3（Co1-xAlx）4O9 （x=0, 0.03, 0.05）, prepared by a sol-gel process, have been investigated in the temperature range 305-20 K. The results indicate that after Al substitution for Co in Ca3（Co1-xAlx）4O9, the direct current electrical resistivity and thermopower increase due to the reduction of carrier concentration. Experiments show that Al substitution results in decreased lattice thermal conductivity. The figure of merit of temperature behavior suggests that Ca3（Co0.97Al0.03）4O9 would be a promising candidate thermoelectric material for high-temperature thermoelectric application.

关键词： transition metal oxides sol-gel process thermoelectricity electrical properties substitution

Effect of solidification mode on microstructure evolution and properties of magnesium alloy with long-period stacking ordered phase

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Journal of Iron and Steel Research International 2024年第5期31卷 1127-1138页

作者： Hao Li hong-mei chen Xu Zhang Qian-hao Zang Jing Zhang Di Feng Yan-xin Qiao Yu-hang Guo School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang212100JiangsuChina School of Metallurgy and Materials Engineering Jiangsu University of Science and TechnologySuzhou215600JiangsuChina

The solidification methods of electromagnetic stirring(EMS)and non-electromagnetic stirring were employed to prepare Mg–6Gd–3Y–xZn–0.6Zr(x=1,1.5,2,3)*** evolution of alloy microstructures and the changes in properties were analyzed for different Zn *** has been observed that in alloys without electromagnetic stirring,as the Zn content increases,the alloy structure gradually *** primary second phase transitions from Mg5RE phase to long-period stacking ordered(LPSO)phase,resulting in improved hardness and *** alloys subjected to electromagnetic stirring,there is a relatively higher content of the second phase,primarily consisting of LPSO *** applying electromagnetic stirring,the quantity and the type of LPSO phase in the alloy *** alloy structure becomes more uniform with electromagnetic stirring,resulting in increased hardness and reduced hardness gradients within the *** mechanical properties of alloys with electromagnetic stirring are superior to those without electromagnetic stirring.

关键词： Rare earth magnesium alloy LPSO phase Electromagnetic stirring Casting Property

Microstructure and properties evolution of Al-17Si-2Fe alloys with addition of quasicrystal Al-Mn-Ti master alloy

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Rare Metals 2020年第10期39卷 1210-1221页

作者： Jing Zhang Zhou-Yi Pang Ling Wang Chi-Chi Sun Ning Liu hong-mei chen Zhao-Xia cheng Ke Li School of Metallurgy and Materials Engineering Jiangsu University of Science and TechnologyZhangjiagang 215600China Zhangjiagang Industrial Technology Research Institute Jiangsu University of Science and TechnologyZhangjiagang 215600China School of Materials Science and Engineering Yingkou Institute of TechnologyYingkou 115014China School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

The Fe-rich intermetallic compounds in Al-17Si-2 Fe were modified via Al-Mn-Ti quasicrystal master *** effect of master alloy content on the Fe-rich phase morphology was studied by scanning electron microscope(SEM)and thermodynamic *** show that the microstructure of the Al-Mn-Ti master alloy consists of binary quasicrystal matrix and ternary AlMnTi secondary *** evolutive tendency of Fe-rich intermetallic compounds with content of quasicrystal Al-Mn-Ti master alloy increasing can be described as follows:long needle-shapedβphase for Al-17 Si-2 Fe alloy,long plate-shaped ternaryδphase for 3 wt%master alloy addition,Chinese-script and polyhedralαphases for 4 wt%master alloy addition and finer plate-shaped quaternaryδphase with a phases for 5 wt%master alloy *** ultimate tensile strength of the Al-17 Si-2 Fe alloy with4 wt%master alloy addition(a mass ratio of w(Mn)/w(Fe)≈0.7)increases by 23.8%and the friction coefficient decreases from 0.45 to 0.35 compared with those of Mnfree alloy.α-Fe phases have less negative effect on the matrix compared with the long needle-shapedβphase and the plate-shapedδphase.

关键词： Fe-rich intermetallic compounds Al-Mn-Ti quasicrystal alloy Microstructure Mechanical properties Friction coefficient

Influences of Asymmetric Reduction Rolling on the Microstructure and Mechanical Properties of AZ91

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Acta Metallurgica Sinica(English Letters) 2018年第7期31卷 673-680页

作者： Yi-Quan Zhao hong-mei chen Jing Zhang Ru Ma Yan-Dong Liu Yi-Nong Wang Ling Wang Qun Zhang Wei-Gang Li School of Materials Science and Engineering Dalian University of TechnologyDalian 116024China Provincial Key Lab of Advanced Welding Technology Jiangsu University of Science and TechnologyZhenjiang 212003China School of Metallurgy and Materials Engineering Jiangsu University of Science and TechnologyZhangjiagang 215600China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Yingkou Institute of Technology Yingkou 115014China Bayuquan Entry-Exit Inspection and Quarantine Bureau Yingkou 115000China

The influence of asymmetric reduction rolling （ARR） on the microstructure, texture and mechanical properties of AZ91 was investigated. The microstructural characteristics of the AZ91 sheet processed by symmetric roiling （SR） were the twins, intersection of twins and dynamic recrystalization （DRX） grains around the coarse grains and within the twins. However, the amount of twins and DRX grains in ARRed AZ91 was much smaller than that in SRed AZ91. The SRed AZ91 after annealing exhibited fine DRX grains and some coarse grains with a size of ~ 100 pro. The grains in ARRed AZ91 after annealing were much finer and more homogeneous than those in SRed AZ91 after annealing. The intensity of basal texture of ARRed AZ91 after annealing was lower than that of SRed AZ91 rolling after annealing. The average Schmid factor of ARRed AZ91 is 0.34, which is higher than that of SRed AZ91. The yield strength and ultimate tensile strength of the ARRed AZ91 sheet were inCreased to 16.1% and 31.8% compared to SRed AZ91 sheet, from 155 to 180 MPa, and from 220 to 290 MPa, respectively. The improvement of mechanical properties in ARRed AZ91 after annealing was attributed to much finer, more homogeneous DRX grains and weaker basal texture.

关键词： AZ91 Asymmetric reduction rolling. Microstructure Texture Mechanical properties

Prediction of lymph node metastasis in early gastric signet-ring cell carcinoma:A real-world retrospective cohort study

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World Journal of Gastroenterology 2023年第24期29卷 3807-3824页

作者： Jia-Jia Yang Xiao-Yong Wang Rui Ma mei-hong chen Guo-Xin Zhang Xuan Li Department of Gastroenterology The First Affiliated Hospital of Nanjing Medical UniversityNanjing 210029Jiangsu ProvinceChina Department of Gastroenterology The Affiliated Changzhou No.2 People's Hospital of Nanjing Medical UniversityChangzhou 213000Jiangsu ProvinceChina Department of Nursing Jiangsu Health Vocational CollegeNanjing 211800Jiangsu ProvinceChina

BACKGROUND Signet-ring cell carcinoma(SRCC)was previously thought to have a worse prognosis than other differentiated gastric cancer(GC),however,recent studies have shown that the prognosis of SRCC is related to pathological *** hypothesize that patients with SRCC and with different SRCC pathological components have different probability of lymph node metastasis(LNM).AIM To establish models to predict LNM in early GC(EGC),including early gastric *** Clinical data from EGC patients who had undergone gastrectomy at the First Affiliated Hospital of Nanjing Medical University from January 2012 to March 2022 were *** patients were divided into three groups based on type:Pure SRCC,mixed SRCC,and non-signet ring cell carcinoma(NSRC).The risk factors were identified through statistical tests using SPSS 23.0,R,and EmpowerStats *** A total of 1922 subjects with EGC were enrolled in this study,and included 249 SRCC patients and 1673 NSRC patients,while 278 of the patients(14.46%)presented with *** analysis showed that gender,tumor size,depth of invasion,lymphovascular invasion,ulceration,and histological subtype were independent risk factors for LNM in *** and analysis using prediction models of EGC showed that the artificial neural network model was better than the logistic regression model in terms of sensitivity and accuracy(98.0%vs 58.1%,P=0.034;88.4%vs 86.8%,P2 cm(OR=5.422,P=0.038).CONCLUSION A validated prediction model was developed to recognize the risk of LNM in EGC a

关键词： Early gastric cancer Signet-ring cell carcinoma Lymph node metastasis Nomogram Prediction model