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Sliding Mode Guidance Law Considering Missile Dynamic Characteristics and Impact Angle Constraints

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International Journal of Automation and computing 2018年第2期15卷 218-227页

作者： Hui-Bo Zhou Jun-Hong song Shen-min song School of Mathematical Sciences Harbin Normal University Center for Control Theory and Guidance Technology Harbin Institute of Technology

In order to improve the precision of guidance for the missile intercepting maneuvering targets, this paper proposes a sliding mode guidance law with impact angle constraints based on the equation of the relative motion of the missile and the target in a 2D plane. Two finite-time convergent guidance laws are proposed based on the nonsingular terminal sliding mode, while, two exponential convergent guidance laws involving dynamic delay are developed through applying the higher-order nonsingular terminal sliding mode. The simulations denote that, in all the four scenarios of the target＇s maneuvering, the guidance laws are able to inhibit the chattering phenomenon of the sliding modes effectively; and from an expected aspect angle, the missiles could attack the targets with high precision and fast speed.

关键词： Autopilot impact angle nonsingular terminal sliding mode finite-time convergent guidance

Effects of temperature and alloying content on the phase transformation and{10■1}twinning in Zr during rolling

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Journal of Materials Science & Technology 2020年第6期41卷 76-80页

作者： Xinglong An Hao Zhang song Ni Xiaoqin Ou Xiaozhou Liao min song State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China School of Aerospace Mechanical and Mechatronic EngineeringThe University of SydneySydneyNSW 2006Australia

The effects of temperature and Ti content on the deformation mechanisms of pure Zr and Zr-Ti alloys were investigated by transmission electron *** results indicate the existence of a relation between deformation-induced phase transformation from a hexagonal close-packed structure to a facecentered cubic structure and{10■1}deformation *** is,when one is suppressed,the other will be *** phase transformation was suppressed while the{10■1}compressive twinning was promoted with increasing the rolling temperature and/or Ti *** can be attributed to the activation of basaldislocations at high temperature and the increased stacking fault energy with Ti content.

关键词： Zr Zr-Ti alloy Twinning Phase transformation Stacking fault energy

Casimir Force at a Finite Cut-Off

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Communications in Theoretical Physics 2008年第12期50卷 1317-1322页

作者： XIONG Ai-min CHEN Xiao-song Institute of Theoretical Physics Chinese Academy of Sciences P.O. Box 2735 Beijing 100080 China

We calculate the Casimir force at a finite cut-off A by summing the forces induced by the all fluctuation modes. We show that the Casimir force is independent of the cut-off function in the limit L∧ → ∞. There is a correction in the order of （L∧）^-2, when L∧ is finite and large. This correction becomes remarkable when L is comparable with the microscopic length scale ∧^-1. It has been demonstrated that the Casimir force at a finite cut-off should be defined by summing forces of all fluctuation modes, instead of the derivative of Casimir energy with respect to L where an additional derivative of the cut-off function has been introduced.

关键词： vacuum fluctuation Casimir force finite cut-off

Liposomes co-loaded with metformin and chlorin e6 modulate tumor hypoxia during enhanced photodynamic therapy

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Nano Research 2017年第4期10卷 1200-1212页

作者： Xuejiao song Liangzhu Feng Chao Liang min Gao Guosheng song Zhuang Liu Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices Soochow University Suzhou 215123 China

Though photodynamic therapy （PDT） has been widely used in the non-invasive destruction of solid tumors, the therapeutic efficacy of PDT is often limited by the hypoxic tumor environment. Herein, we report the innovative use of metformin, an oral hypoglycemic agent commonly used in the treatment of type II diabetes, to improve tumor oxygenation, and overcome tumor hypoxia-associated resistance to PDT. In our design, hydrophilic metformin and modified hydrophobic chlorin e6 （HCe6） are co-encapsulated within the inner cavity and outer membrane of liposomes, respectively. Due to the high uptake of liposome nanoparticles by tumors, and the sustained release of metformin, the intravenous administration of metformin （Met）-HCe6-Liposome nanoparticles greatly improves tumor oxygena- tion in several different tumor models, as revealed by in vivo photoacoustic imaging and ex vivo immunofluorescence staining. Systemic administration of Met-HCe6-Liposomes followed by in vivo PDT achieved significantly improved therapeutic effects compared to that of PDT without metformin. Hence, our study represents a new strategy for the improvement of PDT efficacy through the modulation of tumor oxygenation by clinically approved agents.

关键词： photodynamic therapy liposomes metforrnin tumor hypoxia

Recovery of the Solitons Using a Lattice Boltzmann Model

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Chinese Physics Letters 1999年第2期16卷 109-110页

作者： YAN Guang-wu song min Laboratory for Nonlinear Mechanics of Continuous Media Institute of MechanicsChinese Academy of SciencesBeijing 100080 Department of Mathematics Jilin UniversityChangchun 130023 Division of Foundation Jilin Province Architect CollegeChangchun 130053

We formulate a lattice Boltzmann model which simulates Korteweg-de Vries equation by using a method of higher moments of lattice Boltzmann *** a series of lattice Boltzmann equations in different time scales and the conservation law in time scale t0,we obtain equilibrium distribution *** numerical examples show that the method can be used to simulate soliton.

关键词： equation. function. lattice

Pollution levels and characteristics of phthalate esters in indoor air of offices

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Journal of Environmental Sciences 2015年第2期27卷 157-162页

作者： min song Chenchen Chi min Guo Xueqing Wang Lingxiao Cheng Xueyou Shen College of Environmental & Resource Sciences Zhejiang University Chinese Research Academy of Environmental Sciences The Xinhua Hospital of Zhejiang Province Zhejiang Provincial Key Laboratory of Organic Pollution and Control

The pollution status and characteristics of PAEs（phthalate esters） were investigated in indoor air of offices, and PAEs of both gas-phase and particulate-phase were detected in all the samples. The concentration（sum of the gas phase and the particulate phase） was4748.24 ng/m3, ranging between 3070.09 and 6700.14 ng/m3. Diethyl phthalate, dibutyl phthalate, and di（2-ethylhexyl） phthalate were the most abundant compounds, together accounting for 70% of the ∑ 6PAEs. Dividing the particulate-phase PAEs into four size ranges（〈 2.5, 2.5–5, 5–10, 〉 10 μm）, the result indicated that PAEs in PM2.5were the most abundant,with the proportion of 72.64%. In addition, the PAE concentration in PM2.5correlated significantly with the total particulate-phase PAEs（R2= 0.85）. Thus, the amount of PAEs in PM2.5can be estimated from the total amount of particulate-phase PAEs using this proportion. In a comparison between the offices and a newly decorated study room, it was found that pollution characteristics were similar between these two places. Thus, it is implied that the PAE concentration decreased by 50% 2 yr after decorating.

关键词： Phthalate esters Pollution status Particle size distribution Indoor air Office

Pollution levels and characteristics of phthalate esters in indoor air in hospitals

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Journal of Environmental Sciences 2015年第11期27卷 67-74页

作者： Xueqing Wang min song min Guo Chenchen Chi Feifei Mo Xueyou Shen College of Environmental & Resource Sciences Zhejiang University Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Chinese Research Academy of Environmental Sciences Zhejiang Provincial Key Laboratory of Organic Pollution and Control

The concentrations of phthalate esters（PAEs） in Chinese hospitals were investigated by simultaneously determining concentrations of gas- and particle-phase PAEs. PAEs were detected in two third-class first-grade hospitals, two second-class first-grade hospitals, and a community health service center. Hospital drugstores had the highest concentration（24.19 μg/m3）, which was 1.54 times that of newly decorated houses. The second highest concentration was found in the transfusion rooms, averaging 21.89 μg/m3; this was followed by the concentrations of PAEs in the nurse＇s workstations, the wards, and the doctor＇s offices, with mean concentrations of 20.66, 20.0, and 16.92 μg/m3, respectively. The lowest concentrations were found in the hallways（16.30 μg/m3）. Of the six different kinds of PAEs found, major pollutants included diethyl phthalates, dibutyl phthalates, butylbenzyl phthalates and di（2-ethylhexyl） phthalates, comprising more than 80% of all PAEs ***, a comparison between different wards showed that PAE concentrations in the maternity wards were 1.63 times higher than in the main wards. Based on known health hazards, our results suggest that the PAEs seriously influence the health of the pregnant women and babies; therefore, it is of great importance to take the phthalate concentrations in hospitals into consideration. In addition, hospital indoor air was more seriously contaminated than the air of newly decorated houses.

关键词： Air pollution Hospital Indoor air Phthalate concentrations

Electron beam irradiation induced metastable phase in a Mg-9.8 wt%Sn alloy

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Journal of Materials Science & Technology 2021年第25期84卷 133-138页

作者： Chaoqiang Liu Houwen Chen min song Jian-Feng Nie State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083China College of Materials Science and Engineering Chongqing UniversityChongqing400044China Electron Microscopy Center Chongqing UniversityChongqing400044China Department of Materials Science and Engineering Monash UniversityVictoria3800Australia

Aberration-corrected scanning transmission electron microscopy has been used to study a novel metastable phase,designated asβ’’phase,induced to form by electron beam irradiation in a Mg-9.8 wt.%Sn *** phase is spherical in three dimensions,having a D019 structure with the lattice parameters of a=0.642 nm,c=0.521 nm and space group of P63/*** chemical formula is Mg_(3)Sn,like theβ’metastable precipitate *** orientation relationship between theβ’’phase and theα-Mg matrix is such that■_(β)’’//■_(α)and(0001)_(β)’’//(0001)_(α).Its formation involves solely the ordering of Sn atoms in the solid solution magnesium ***-principles calculations indicate that the formation of theβ’’phase is energetically favored.

关键词： Mg-Sn alloys Metastable phase Irradiation HAADF-STEM Density functional theory

A real-time detection and positioning method for small and weak targets using a 1D morphology-based approach in 2D images

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Light(Science & Applications) 2018年第1期7卷 1063-1071页

作者： min-song Wei Fei Xing Zheng You Department of Precision Instrument Tsinghua UniversityBeijing 100084China State Key Laboratory of Precision Measurement Technology and Instruments Tsinghua UniversityBeijing 100084China Department of Mechanical Engineering University of CaliforniaBerkeleyCA 94720USA

A small and weak target detection method is proposed in this work that outperforms all other methods in terms of real-time *** is the first time that two-dimensional(2D)images are processed using only one-dimensional1D structuring elements in a morphology-based approach,enabling the real-time hardware implementation of the whole image processing method.A parallel image readout and processing structure is introduced to achieve an ultra-low latency time on the order of nanoseconds,and a hyper-frame resolution in the time domain can be achieved by combining the row-by-row structure and the electrical rolling shutter *** results suggest that the expected target can be successfully detected under various interferences with an accuracy of 0.1 pixels(1σ)under the worst sky night test condition and that a centroiding precision of better than 0.03 pixels(1σ)can be reached for static *** real-time detection method with high robustness and accuracy is attractive for application to all types of real-time small target detection systems,such as medical imaging,infrared surveillance,and target measurement and tracking,where an ultra-high processing speed is required.

关键词： high robustness and accuracy 1D morphology-based approach row-by-row structure real-time detection method small and weak target detection and positioning