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Surrogate-Assisted Particle Swarm Optimization Algorithm With Pareto Active Learning for Expensive Multi-Objective Optimization

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IEEE/CAA Journal of Automatica Sinica 2019年第3期6卷 838-849页

作者： Zhiming lv Linqing Wang Zhongyang Han jun Zhao wei Wang IEEE the Faculty of Electronics Information and Electrical Engineering Dalian University of Technology

For multi-objective optimization problems, particle swarm optimization(PSO) algorithm generally needs a large number of fitness evaluations to obtain the Pareto optimal solutions. However, it will become substantially time-consuming when handling computationally expensive fitness functions. In order to save the computational cost, a surrogate-assisted PSO with Pareto active learning is proposed. In real physical space(the objective functions are computationally expensive), PSO is used as an optimizer, and its optimization results are used to construct the surrogate models. In virtual space, objective functions are replaced by the cheaper surrogate models, PSO is viewed as a sampler to produce the candidate solutions. To enhance the quality of candidate solutions, a hybrid mutation sampling method based on the simulated evolution is proposed, which combines the advantage of fast convergence of PSO and implements mutation to increase diversity. Furthermore, ε-Pareto active learning(ε-PAL)method is employed to pre-select candidate solutions to guide PSO in the real physical space. However, little work has considered the method of determining parameter ε. Therefore, a greedy search method is presented to determine the value ofεwhere the number of active sampling is employed as the evaluation criteria of classification cost. Experimental studies involving application on a number of benchmark test problems and parameter determination for multi-input multi-output least squares support vector machines(MLSSVM) are given, in which the results demonstrate promising performance of the proposed algorithm compared with other representative multi-objective particle swarm optimization(MOPSO) algorithms.

关键词： Multiobjective optimization Pareto active learning particle swarm optimization (PSO) surrogate

Research Progress of Optical H2O Sensor With a DFB Diode Laser

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Photonic Sensors 2014年第2期4卷 113-119页

作者： Guangping lv jun CHANG Qingpu WANG Qiang WANG wei wei School of Information Science and Engineering and Shandong Provincial Key Laboratory of Laser Technology andApplication Shandong University Jinan 250100 China

In the field of near infrared H2O sensing, the acquisition of the absorption signal usually is from a noisy background, thus it is important to adopt an effective signal demodulation method. This study introduced the research progress in the field of trace water vapor detection, covering different individual gas detection techniques. On the basis of the conventional double-beam differential absorption, the division method in voltage and the dual-peak method based on the differential value of two adjacent absorption lines have been studied. Voltage division has an excellent stability to temperature variation, mechanical extrusion, and fiber bend loss. The dual-peak method proved a linear relation with the water vapor concentration, and this method provided a way to measure the concentration at high pressure. Furthermore, the so called balanced ratiometer detection （BRD） was introduced. It has an outstanding self-adjusting capability, and it can also avoid an excess phase difference caused by the current-to-voltage converting circuit, thus this method has a high sensitivity. In addition, the second harmonic technique applied to gas detection was introduced, and for the high-frequency modulation via driving current, l/f was suppressed apparently; as a result, this technique realized a better sensitive detection by one to two orders of magnitude.

关键词： Water vapor gas sensing DFB diode laser absorption spectrum

Persistent alterations in gray matter in COVID-19 patients experiencing sleep disturbances:a 3-month longitudinal study

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Neural Regeneration Research 2025年第10期20卷 3013-3024页

作者： Kaixuan Zhou Gaoxiong Duan Ying Liu Bei Peng Xiaoyan Zhou Lixia Qin Lingyan Liang Yichen wei Qingping Zhang Xiaocheng Li Haixia Qin Yinqi Lai Yian Lu Yan Zhang Jiazhu Huang Jinli Huang Yinfei Ouyang Bolin Bin Mingming Zhao jun Liu Jianrong Yang Demao Deng Guangxi Key Laboratory of Special Biomedicine School of MedicineGuangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology the People’s Hospital of Guangxi Zhuang Autonomous RegionGuangxi Academy of Medical SciencesNanningGuangxi Zhuang Autonomous RegionChina Department of Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Guangxi Clinical Research Center for Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina

Sleep disturbances are among the most prevalent neuropsychiatric symptoms in individuals who have recovered from severe acute respiratory syndrome coronavirus 2 *** studies have demonstrated abnormal brain structures in patients with sleep disturbances who have recovered from coronavirus disease 2019(COVID-19).However,neuroimaging studies on sleep disturbances caused by COVID-19 are scarce,and existing studies have primarily focused on the long-term effects of the virus,with minimal acute phase *** a result,little is known about the pathophysiology of sleep disturbances in the acute phase of *** address this issue,we designed a longitudinal study to investigate whether alterations in brain structure occur during the acute phase of infection,and verified the results using 3-month follow-up data.A total of 26 COVID-19 patients with sleep disturbances(aged 51.5±13.57 years,8 women and 18 men),27 COVID-19 patients without sleep disturbances(aged 47.33±15.98 years,9 women and 18 men),and 31 age-and gender-matched healthy controls(aged 49.19±17.51 years,9 women and 22 men)were included in this *** COVID-19 patients with sleep disturbances were included in a longitudinal *** found that COVID-19 patients with sleep disturbances exhibited brain structural changes in almost all brain *** cortical thicknesses of the left pars opercularis and left precuneus were significantly negatively correlated with Pittsburgh Sleep Quality Index ***,we observed changes in the volume of the hippocampus and its subfield regions in COVID-19 patients compared with the healthy *** 3-month follow-up data revealed indices of altered cerebral structure(cortical thickness,cortical grey matter volume,and cortical surface area)in the frontal-parietal cortex compared with the baseline in COVID-19 patients with sleep *** findings indicate that the sleep disturbances patients had altered morphology in the cortical an

关键词： brain structure cortical gray matter volume cortical surface area cortical thickness hippocampus magnetic resonance imaging Pittsburgh Sleep Quality Index severe acute respiratory syndrome coronavirus 2 infections sleep disturbances sub-cortical volume

Effects of Heat Treatment and Additive LiF on the Properties of Solid-State Electrolyte of Li_(1.5)Al_(0.5)Ge_(1.5)(PO_(4))_(3)

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Energy & Environmental Materials 2021年第2期4卷 208-212页

作者： Jinhang lv Ruilin Zheng Peng lv wei wei College of Electronic and Optical Engineering Nanjing University of Posts and Telecommunications9 Wenyuan RoadNanjing Jiangsu 210023China

A solid electrolyte of LAGP[Li_(1.5)Al_(0.5)Ge_(1.5)(PO_(4))_(3)]contained 0.5 wt%Li F was prepared by using low-volatile raw *** effects of different heat treatment conditions(750–900°C,4–10 h)and additive(Li F)on the ionic conductivity,structural morphology,and crystal transformation process were investigated in ***(electrochemical impedance spectroscopies)showed that the ionic conductivity of LAGP contained 0.5 wt%Li F had a highest value of 3.17×10^(-4)S cm^(-1)with low activation energy(0.31 e V)after treating 825°C for 6 h,more than LAGP of 2.45×10^(-4)S cm^(-1).DSC analysis and SEM images indicated that adding a small amount of Li F to LAGP not only can lower the glass transition temperature(from 513°C to507°C)and crystallization temperature(from 622°C to 605°C),but also can modify the grain boundary and increase the relative density of LAGP(from 95.8%to 97.7%).

关键词： glass ceramics grain boundary ionic conductivity LAGP solid-state electrolytes

Mesh Conditions of the Preserving-Maximum-Principle Linear Finite Volume Element Method for Anisotropic Diffusion-Convection-Reaction Equations

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Acta Mathematicae Applicatae Sinica 2023年第3期39卷 707-732页

作者： Lei LIN jun-liang lv Jing-yan YUE Guang-wei YUAN School of Mathematics Jilin UniversityChangchun 130012China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China

We develop mesh conditions for linear finite volume element approximations of anisotropic diffusionconvectionreaction problems to satisfy the discrete maximum *** obtain the sufficient conditions to gurantee the both upper and lower bounds of the numerical solution when each angle of arbitrary triangle is O(∥q∥_∞h+∥g∥_∞h~2)-acute and h is small enough,where h denotes the mesh size,q and g are coefficients of the convection and reaction terms,*** deal with the convection-dominated problems,we use the upwind triangle *** such scheme,the mesh condition can be sharper to O(∥g∥_∞h~2)-*** numerical examples are presented to demonstrate the theoretical results.

关键词： anisotropic diffusion-convection-reaction equation finite volume element method discrete maximum principle

Recent advances in platelet engineering for anti-cancer therapies

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Particuology 2022年第5期20卷 2-13页

作者： Yanlin lv wei wei Guanghui Ma State Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

Platelets contribute a major role in hemostasis by clumping and coagulation at the site of blood vessel *** light of recent findings of a close relationship between platelets and immunological response,as well as interactions between platelets and cancer cells,novel engineering strategies have emerged for the integration of platelets or platelet membrane(PM)with anti-cancer *** this review,we discuss several recent innovations that use platelets or their membranes to circumvent host immune responses and target tumor cells with high specificity to deliver a range of pharmacological,photothermal,or immunologic agents for eradication of recalcitrant tumor *** specifically,we compare the relative advantages of using whole platelets versus single or hybrid PM to coat nanoparticle *** cargoes range from well-established anti-tumor apoptosis-inducing agents,to relatively new photothermal agents that can induce a feedback cascade in which they induce vascular damage to the tumor which recruits more platelet-or membrane-encapsulated agents to induce further *** also discuss the use of engineered platelets to produce programmed cell death-inducing platelet derived *** review provides an overview and future directions for this promising platelet-based biomimetic approach to anti-cancer therapy.

关键词： Engineering platelets Platelet-mimicking Drug delivery Anti-cancer therapy

Effect of strain-induced precipitation on microstructure and properties of titanium micro-alloyed steels

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Journal of Iron and Steel Research International 2022年第6期29卷 983-993页

作者： Xiang-dong Huo Zhi-wei lv Chen Ao Lie-jun Li Ji-nian Xia Song-jun Chen School of Material Science and Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510640GuangdongChina Iron and Steel Research Institute Shandong Iron and Steel Group Rizhao Co.Ltd.Rizhao 276826ShandongChina

The strain-induced precipitation behavior of titanium micro-alloyed steel was examined through the stress relaxation *** addition,the relationship between strain-induced precipitation and isothermal precipitation was *** findings revealed that the strain-induced precipitation and recrystallization processes of titanium micro-alloyed steel coexist and compete at the same *** results also showed that the recrystallization process was inhibited with straininduced ***,a large amount of nano-sized TiC particles precipitated in Ti micro-alloyed ***,the strain-induced precipitated TiC had a size of 10 nm and isothermally precipitated TiC had a size of 3–6 ***,there was a clear competitive relationship between strain-induced precipitation and isothermal *** findings also showed that strain-induced precipitation had an obvious effect on the refinement of austenite although the effect was not obvious on the increase in the yield ***,isothermal treatment was shown to be more advantageous than strain-induced ***,the major increase in the yield strength was mainly attributed to the precipitation strengthening of nano-sized TiC during isothermal precipitation.

关键词： Ti micro-alloyed steel Stress relaxation Nanometer-carbide Strain-induced precipitation Isothermal precipitation

Static and dynamic evolution of CO adsorption onγ-U(100)surface with different levels of Mo doping using DFT and AIMD calculations

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Nuclear Science and Techniques 2023年第9期34卷 142-154页

作者： jun-wei Li wei-Min Jia Chong Liu Sha-Sha lv Jin-Tao Wang Zheng-Cao Li Key Lab of Advanced Materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Xi’an Research Institute of High-Technology Xi’an 710025China Key Laboratory of Beam Technology(MOE) College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China

Alloys of uranium and molybdenum are considered as the future of nuclear fuel and defense ***,surface corrosion is a fundamental problem in practical applications and *** this study,the static and dynamic evolution of carbon monoxide(CO)adsorption and dissociation onγ-U(100)surface with different Mo doping levels was investigated based on density functional theory and ab initio molecular *** the static calculation phase,parameters,such as adsorption energy,configuration,and Bader charge,were evaluated at all adsorption ***,the time-dependent behavior of CO molecule adsorption were investigated at the most favorable *** minimum energy paths for CO molecu-lar dissociation and atom migration were investigated using the transition state search *** results demonstrated that the CO on the uranium surface mainly manifests as chemical adsorption before dissociation of the CO *** CO molecule exhibited a tendency to rotate and tilt upright ***,it is difficult for CO adsorption on the surface in one of the configurations with CO molecule in vertical direction but oxygen(O)is closer to the *** charge illustrates that the charge transfers from slab atoms to the 2π*antibonding orbital of CO molecule and particularly occurs in carbon(C)*** time is less than 100 fs for the adsorptions that forms embryos with tilt upright in dynamics *** density of states elucidates that the overlapping hybridization of C and O 2p orbitals is mainly formed via the d orbitals of uranium and molybdenum(Mo)atoms in the dissociation and re-adsorption of CO *** conclusion,Mo doping of the surface can decelerate the adsorption and dissociation of CO molecules.A Mo-doped surface,created through ion injection,enhanced the resistance to uranium-induced surface corrosion.

关键词： Adsorption and dissociation Uranium CO molecule Density functional theory Ab initio molecular dynamics

Effects of Na_(2)CO_(3)on reduction mechanism and kinetics of iron during deep reduction of ilmenite concentrate

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Journal of Iron and Steel Research International 2023年第3期30卷 419-428页

作者： Xiao-dong lv You-ling Hou Yun-tao Xin wei lv Xue-wei lv Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

High-quality upgraded titanium slag obtained through semi-molten reduction with the addition of Na_(2)CO_(3)is important for the fluidizing chlorination process to produce TiO_(2)*** key is the effect of Na_(2)CO_(3)on the reduction behavior of ***,the effects of Na_(2)CO_(3)on reduction mechanism and kinetics of iron during deep reduction of ilmenite concentrate were *** results indicated that the metallization ratio of the reduced sample increased with increasing temperature,time,and dose of Na_(2)CO_(3).The addition of Na_(2)CO_(3)significantly accelerated the reduction of iron in the ilmenite concentrate and promoted the growth of iron ***,the addition of Na_(2)CO_(3)produced sodium iron titanates;thus,the metallization ratio of the sample decreased with an increase in the temperature and time when the temperature was above 1200℃and the time was more than 30 *** the doses of Na_(2)CO_(3)were 0,3,and 6 wt.%,the reduction of iron was controlled by the interfacial chemical reaction,both the interfacial chemical reaction and diffusion,and diffusion,respectively,and the apparent activation energies were 134.91,64.89,and 120.82 kJ/mol,respectively.

关键词： Ilmenite concentrate Sodium carbonate Metallization ratio Reduction mechanism Kinetics