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Chinese Science Bulletin 2008年第12期53卷 1905-1912页

作者： XU HaiMing wang linwei HE JinHai Jiangsu Key Laboratory of Meteorological Disaster and College of Atmospheric Sciences Nanjing University of Information Scienceand Technology Nanjing 210044 China

High-resolution satellite measurements are used to study the air-sea interaction over the Kuroshio Extension (KE) region during spring time. There are two oceanic fronts in the KE region off the east coast of Japan. These fronts are generally associated with strong ocean currents, which may display unstable meander, resulting in remarkable warm sea surface temperature (SST) ridges and cold SST troughs. Analyses of these satellite observations reveal a significantly positive correlation between sea surface wind speed and its underlying SST along these fronts. This positive SST-wind correlation be-comes even more significant when strong meanders occur along the fronts. This positive SST-wind correlation indicates an ocean-to-atmosphere feedback over the KE region during spring time. A high-resolution regional atmospheric model is used to investigate the atmospheric response to SST changes along the two fronts.

关键词：大气圈黑潮海洋春季

Investigation of thermochemical process of coal particle packed bed reactions for the development of UCG

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International Journal of Coal Science & Technology 2020年第3期7卷 476-492页

作者： Tata Sutardi linwei wang Nader Karimi Manosh C.Paul Systems Power and Energy Research DivisionJames Watt School of EngineeringUniversity of GlasgowGlasgowG128QQUK The Agency for Assessment and Application of Technology(BPPT) JakartaRepublic of Indonesia Centre for Renewable Energy Systems Technologies(CREST) Wolfson School of MechanicalElectrical and Manufacturing EngineeringLoughborough UniversityLeicestershireLE113TUUK School of Engineering and Materials Science Queen Mary University of LondonLondon1E 4NSUK

In this study,a packed bed reactor was developed to investigate the gasification process of coal *** effects of coal particle size and heater temperature of reactor were examined to identify the thermochemical processes through the packed *** different coal samples with varying size,named as A,B,and C,are used,and the experimental results show that the packed bed with smaller coal size has higher temperature,reaching 624°C,582°C,and 569°C for coal A,B,and C,*** the case of CO formation,the smaller particle size has greater products in the unit of mole fraction over the area of ***,the variation in the porosity of the packed bed due to different coal particle sizes affects the reactions through the oxygen ***,the CO formation is least from the coal packed bed formed by the smallest particle size A.A second test with the temperature variations shows that the higher heater temperature promotes the chemical reactions,resulting in the increased gas *** findings indicate the important role of coal seam porosity in underground coal gasification application,as well as temperature to promote the syngas productions.

关键词： Thermochemical process Particle packed bed Coal particle gasification Gas products Underground coal gasification(UCG)

Novel modeling on numerical computing the geo-deformation information in coalmine based on the GIS-Excel

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High Technology Letters 2013年第2期19卷 156-161页

作者：杨可明 wang Libo Zhang Tao Qian Xiaoli wang linwei Liu Shiwen College of Geoscience and Surveying Engineering China University of Mining & Technology(Beijing)

Numerical simulation modeling is a hotspot in the geological engineering computing field. Tak- ing a fast Langrangian analysis of continua in 3 dimensions （FLAC3D） numerical modeling on com- puting the geo-deformation information caused by the mining subsidence in a coalmine for example, a new GIS-Excel modeling method is proposed to build geologic strata within the simulation range combined with the coal-seam dip angle of the underground mining working-planes. First of all, the coal-seam model of the numerical computing is built by using the geographic information system （GIS） according to the stripe-through principle and the calculating formula on the size of the model blocks in the paper defined, then the FLAC3D numerical computing model of all geologic strata with- in the simulation range is also built based on the calculating formula of thickness of each stratum and the Excel fast computing advantages. The GIS-Excel method is good at the higher modeling accuracy, seldom making mistakes and consuming less time. The reliability and validity of the method is veri- fied well by its practical applications in the coalmine area.

关键词： numerical simulation mining subsidence fast Langrangian analysis of continua in 3dimensions ( FLAC3D) modeling geo-deformation information geographic information system (GIS)

Segmentation of Hematoxylin-Eosin stained breast cancer histopathological images based on pixel-wise SVM classifier

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Science China(Information Sciences) 2015年第9期58卷 56-68页

作者： QU AiPing CHEN JiaMei wang linwei YUAN JingPing YANG Fang XIANG QingMing MASKEY Ninu YANG GuiFang LIU Juan LI Yan State Key Laboratory of Software Engineering School of Computer Wuhan University Center of High Performance Computing Huaihua University Department of Oncology Zhongnan Hospital of Wuhan University Hubei Key Laboratory of Tumor Biological Behaviors & Hubei Cancer Clinical Study Center Department of Pathology Zhongnan Hospital of Wuhan University

Hematoxylin-Eosin(HE) staining is the routine diagnostic method for breast cancer(BC), and large amounts of HE stained histopathological images are available for analysis. It is emergent to develop computational methods to efficiently and objectively analyze these images, with the aim of providing potentially better diagnostic and prognostic information for BC. This work focuses on analyzing our in-house HE stained histopathological images of breast cancer tissues. Since tumor nests(TNs) and stroma morphological characteristics can reflect the biological behaviors of breast invasive ductal carcinoma(IDC), accurate segmentation of TNs and the stroma is the first step towards the subsequent quantitative analysis. We first propose a method based on the pixel-wise support vector machine(SVM) classifier for segmenting TNs and the stroma, then extract four morphological characters related to the TNs from the images and investigate their relationships with the patients’ 8-year disease free survival(8-DFS). The evaluation result shows that the classification based segmentation method is able to distinguish between TNs and stroma with 87.1% accuracy and 80.2% precision,suggesting that the proposed method is promising in segmenting HE stained IDC histopathological images. The Kaplan-Meier survival curves show that three morphological characters(number of TNs, total perimeter, and average area of TNs) in the images have statistical correlations with 8-DFS of the patients, illustrating that the segmented images can help to identify new morphological factors in IDC TNs for the prediction of BC prognosis.

关键词： breast cancer histopathology images segmentation image analysis support vector machine survival analysis

Three-dimensional cellular automata based particle flow simulations of mechanical properties of talus deposit

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Journal of Rock Mechanics and Geotechnical Engineering 2012年第4期4卷 375-384页

作者： linwei wang Weiya Xu Anquan Xu Geotechnical Research Institute Hohai University College of Hydraulic and Environment Engineering China Three Gorges University Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai University

Based on three-dimensional cellular automata （CA）, a new stochastic simulation model to simulate the microstructures and particle flow of talus deposit is proposed. Ill addition, an auto-modeling program CARS is developed, with which nunaerical simulations can be conducted conveniently. For the problem of simulating mechanical behaviors of talus deposit, spatial anangement or sphere shapes should be considered. In the new modeling method, four sphere anangement models are developed for the particle flow simulation of talus deposit. Numerical results show that the talus deposit has the mechanical characteristics of typical stress-strain curves, as other rock-like materials. The cohesion of talus deposit decreases with increasing rock content, while the internal friction angle increases with increasing rock contents. Finally, numerical simulation is verified with the results of field test.

关键词： soil mechanics talus deposit: three-dimensional cellular automata (CA) particle flow mechanical properties

Contribution of high risk groups’unmet needs may be underestimated in epidemic models without risk turnover:A mechanistic modelling analysis

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Infectious Disease Modelling 2020年第1期5卷 549-562页

作者： Jesse Knight Stefan D.Baral Sheree Schwartz linwei wang Huiting Ma Katherine Young Harry Hausler Sharmistha Mishra MAP Centre for Urban Health Solutions Unity Health TorontoCanada Deptartment of Epidemiology Johns Hopkins Bloomberg School of Public HealthUSA TB HIV Care South Africa Division of Infectious Disease Department of MedicineUniversity of TorontoCanada Institute of Health Policy Management and EvaluationDalla Lana School of Public HealthUniversity of TorontoCanada Institute of Medical Sciences University of TorontoCanada

Background:Epidemic models of sexually transmitted infections(STIs)are often used to characterize the contribution of risk groups to overall transmission by projecting the transmission population attributable fraction(tPAF)of unmet prevention and treatment needs within risk ***,evidence suggests that STI risk is dynamic over an individual’s sexual life course,which manifests as turnover between risk *** sought to examine the mechanisms by which turnover influences modelled projections of the tPAF of high risk ***:We developed a unifying,data-guided framework to simulate risk group turnover in deterministic,compartmental transmission *** applied the framework to an illustrative model of an STI and examined the mechanisms by which risk group turnover influenced equilibrium prevalence across risk *** then fit a model with and without turnover to the same risk-stratified STI prevalence targets and compared the inferred level of risk heterogeneity and tPAF of the highest risk group projected by the two ***:The influence of turnover on group-specific prevalence was mediated by three main phenomena:movement of previously high risk individuals with the infection into lower risk groups;changes to herd effect in the highest risk group;and changes in the number of partnerships where transmission can *** turnover led to a smaller ratio of STI prevalence between the highest and lowest risk *** to the fitted model without turnover,the fitted model with turnover inferred greater risk heterogeneity and consistently projected a larger tPAF of the highest risk group over ***:If turnover is not captured in epidemic models,the projected contribution of high risk groups,and thus,the potential impact of prioritizing interventions to address their needs,could be *** aid the next generation of tPAF models,data collection efforts to parameterize risk group turnover should be prioritized.

关键词： Mathematical modelling Transmission Risk heterogeneity Turnover Sexually transmitted infection Population attributable fraction

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功果桥水电站主要工程地质问题及对策

水力发电 2011年第10期37卷 25-27页

作者：王林维王蕾中国水电顾问集团西北勘测设计研究院工程勘察研究分院甘肃兰州730050

功果桥水电站工程枢纽区地质条件较为复杂,地层呈单斜构造,横河展布,岩层陡倾上游偏右岸;岩体风化、卸荷作用强烈,陡倾角结构面发育,缓倾结构面轻度发育;地下洞室深埋于微风化～新鲜岩体中,围岩为陡倾层状岩体。针对工程开挖中存在的主... 详细信息

功果桥水电站工程枢纽区地质条件较为复杂,地层呈单斜构造,横河展布,岩层陡倾上游偏右岸;岩体风化、卸荷作用强烈,陡倾角结构面发育,缓倾结构面轻度发育;地下洞室深埋于微风化～新鲜岩体中,围岩为陡倾层状岩体。针对工程开挖中存在的主要工程地质问题,提出相应的处理措施,为工程的顺利进行奠定了坚实的基础。

关键词：工程地质问题预测分析处理措施功果桥水电站

Mg共掺杂Gd_(3)(Al,Ga)_(5)O_(12):Ce晶体快发光的作用机理

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无机材料学报 2022年第10期37卷 1123-1128页

作者：李铭清王林伟丁栋舟冯鹤上海大学材料科学与工程学院上海200444 中国科学院上海硅酸盐研究所上海201899

Gd_(3)(Al,Ga)_(5)O_(12):Ce(GAGG:Ce)闪烁体综合性能优异,应用前景广阔。为加快GAGG的发光衰减速度,本研究通过提拉法生长了Mg共掺的Gd_(3)(Al,Ga)_(5)O_(12):Ce单晶。测试结果显示,随着Mg^(2+)掺杂浓度增加,晶体的闪烁衰减速度加快,... 详细信息

Gd_(3)(Al,Ga)_(5)O_(12):Ce(GAGG:Ce)闪烁体综合性能优异,应用前景广阔。为加快GAGG的发光衰减速度,本研究通过提拉法生长了Mg共掺的Gd_(3)(Al,Ga)_(5)O_(12):Ce单晶。测试结果显示,随着Mg^(2+)掺杂浓度增加,晶体的闪烁衰减速度加快,光输出降低。传统解释认为,Mg^(2+)通过电荷补偿作用将部分Ce^(3+)转换成Ce^(4+),后者的发光速度更快。本研究尝试从缺陷的形成与抑制的角度来讨论Mg改善GAGG:Ce晶体闪烁性能的作用机理。由于Ce的离子半径比Gd大,Ce离子掺入将导致发光中心Ce_(Gd)附近的晶格发生畸变。畸变结果为近邻的八面体格位空间变大,反位缺陷将更容易在这些变大的八面体格位形成。最终每个发光中心Ce_(Gd)被四个反位缺陷Gd_(Al)包裹,后者捕获载流子,延缓从基体到发光中心的能量传递,导致发光速度变慢。由于Mg的离子半径介于Gd和Al之间,Mg_(Al)将更容易在上述畸变的八面体格位形成,这会抑制反位缺陷Gd_(Al)在发光中心Ce_(Gd)附近形成(或富集),最终降低(甚至消除)反位缺陷对发光中心的不良影响。XEL测试结果显示,随着Mg掺杂量增大,与反位缺陷相关的发射峰强度变弱,这可以证明Mg对反位缺陷有抑制作用。

关键词：闪烁体 GAGG:Ce 反位缺陷衰减时间

襟翼控制的欠驱动飞行器自抗扰/鲁棒控制系统设计

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兵工学报 2023年第5期44卷 1251-1266页

作者：马悦萌王琳玮邵春涛周荻王永海哈尔滨工业大学航天学院黑龙江哈尔滨150001 哈尔滨工业大学(威海)信息科学与工程学院山东威海264200 北京航天长征飞行器研究所北京100076

针对含不稳定内动态的襟翼控制欠驱动高超声速飞行器现有控制策略普遍存在的机动性能不足、工程应用困难等问题,设计欠驱动飞行器的自抗扰/鲁棒控制系统。提出一种基于通道级联的欠驱动控制策略,令偏航通道作为滚转通道的内回路,利用±... 详细信息

针对含不稳定内动态的襟翼控制欠驱动高超声速飞行器现有控制策略普遍存在的机动性能不足、工程应用困难等问题,设计欠驱动飞行器的自抗扰/鲁棒控制系统。提出一种基于通道级联的欠驱动控制策略,令偏航通道作为滚转通道的内回路,利用±1.5°的侧滑角合法波动范围,提升滚转角的指令跟踪速度。结合自抗扰与鲁棒控制理论设计自动驾驶仪,该自动驾驶仪不仅适用于过载反馈/欠驱动的非最小相位对象,还在摆脱自抗扰系统对关键模型参数依赖的同时减小了鲁棒控制器的降阶难度,有广阔的工程应用前景。为验证方案有效性,以参数存在±20%随机摄动的欠驱动高超声速飞行器模型为对象进行了1000次蒙特卡洛仿真,结果表明新的欠驱动策略能够在保证侧滑角不越界的同时提高滚转通道的响应速度,自抗扰/鲁棒控制系统在面对模型摄动与复合干扰时均有较好的鲁棒性。

关键词：高超声速飞行器襟翼欠驱动控制自抗扰控制鲁棒控制非最小相位

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非农职业经历、土地流转对家庭农场主农业生产生态自觉性的影响效应

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西北农林科技大学学报（社会科学版） 2024年第2期24卷 115-126页

作者：王林蔚霍学喜孔荣西北农林科技大学经济管理学院陕西杨凌712100

基于陕西省564户种植业家庭农场微观调研数据,在考虑样本选择偏差和家庭农场异质性基础上,采用倾向匹配得分(PSM)模型探究非农职业经历对家庭农场主农业生产生态自觉性的净效应,并运用中介效应模型分析土地流转视角下非农职业经历影响... 详细信息

基于陕西省564户种植业家庭农场微观调研数据,在考虑样本选择偏差和家庭农场异质性基础上,采用倾向匹配得分(PSM)模型探究非农职业经历对家庭农场主农业生产生态自觉性的净效应,并运用中介效应模型分析土地流转视角下非农职业经历影响家庭农场主农业生产生态自觉性的作用机理。研究发现:非农职业经历对家庭农场主农业生产生态自觉性具有显著正向影响,具有高中及以上学历、高龄农场主非农职业经历对农业生产生态自觉性的影响效应较为显著;非农职业经历通过扩大土地流转规模和延长土地流转期限提高家庭农场主农业生产生态自觉性,且土地流转规模的中介效应影响更大。因此,政府应完善具备非农职业经历群体返乡创业激励机制,加大对家庭农场等新型经营主体农业生态生产政策支持力度,并适度推进土地流转规模扩张及土地流转期限长期化,推动农业生产可持续发展。

关键词：家庭农场主非农职业经历生态自觉性农业生产土地流转