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生命共同体、环境正义与可持续发展——欧阳黔森创作中生态意识的三个维度

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凯里学院学报 2024年第2期42卷 49-54页

作者：潘琴梁启俊凯里学院人文学院贵州凯里556011

在现代性语境中用“生态”理论来解读极具生态化的乡土文学,是以另一种姿态重新打开了人与自然之间关系的思考。欧阳黔森这位具有独特职业身份和满怀文化忧思的作家,在创作中充分体现出在现代性语境中具有强烈的生态意识情怀:一是作为... 详细信息

在现代性语境中用“生态”理论来解读极具生态化的乡土文学,是以另一种姿态重新打开了人与自然之间关系的思考。欧阳黔森这位具有独特职业身份和满怀文化忧思的作家,在创作中充分体现出在现代性语境中具有强烈的生态意识情怀:一是作为生命共同体的生态意识凸显;二是关于环境正义的生态意识审视;三是可持续发展的生态意识显露。

关键词：欧阳黔森生态意识生命共同体环境正义可持续发展

Reaction Products of MgO and Microsilica Cementitious Materials at Different Temperatures

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Journal of Wuhan University of Technology(Materials Science) 2011年第4期26卷 745-748页

作者：韦江雄 School of Materials Science and Engineering South China University of Technology

The paste was prepared by mixing MgO, microsilica and H2. in the presence of water reducer at different reaction ratios and temperatures, and characterized by XRD, DTA, TGA, IR, and solid-state 2.Si NMR. The experimental results showed that, besides Mg（OH）2. magnesium silicate hydrate （M-S-H） was formed at a low temperature such as 2. and 50 ℃. At a high temperature of 100 ℃, Mg（OH）2.can be further transformed into M-S-H completely, for instance, within ca. 1 month in an excess of microsilica. The average composition and structure of M-S-H was mainly related to the reaction mixture and curing temperature and was discussed in detail.

关键词： MgO microsilica magnesium silicate hydrate (M-S-H)

Crystal-Plasticity-Based Dynamic Constitutive Model of AZ31B Magnesium Alloy at Elevated Temperature and with Explicit Plastic-Strain-Rate Control

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Acta Mechanica Solida Sinica 2020年第1期33卷 31-50页

作者： qijun Xie Zhiwu Zhu Guozheng Kang Key Laboratory of Mountain Hazards and Earth Surface Processes Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China State Key Laboratory of Traction Power Southwest Jiaotong UniversityChengdu 610031China Applied Mechanics and Structure Safety Key Laboratory of Sichuan Province School of Mechanics and EngineeringSouthwest Jiaotong UniversityChengdu 610031China

In this study,a series of experiments were carried out on the AZ31B magnesium alloy,including both a macro-experiment(mechanical experiment)and a micro-experiment(dislocation observation).Next,based on the consideration of the deformation mechanism of magnesium alloys(dislocation slip and twinning),a dynamic constitutive model of the magnesium alloy was *** the developed model,the strain-rate-sensitivity control and the effect of temperature on the dynamic mechanical performance of the alloy were also *** model parameters were determined by fitting the macroscopic experimental ***,the evolution of the micro-deformation mechanism was calculated by the developed model,and the trend of macro-mechanical behavior was also discussed.

关键词： Magnesium alloy Constitutive model Microscopic mechanism Dynamic test Crystal plasticity

A Dynamic Micromechanical Constitutive Model for Frozen Soil under Impact Loading

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Acta Mechanica Solida Sinica 2016年第1期29卷 13-21页

作者： qijun Xie Zhiwu Zhu Guozheng Kang School of Mechanics and Engeering Southwest Jiaotong University State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academic Sciences State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology

By taking the frozen soil as a particle-reinforced composite material which consists of clay soil （i.e., the matrix） and ice particles, a micromechanical constitutive model is established to describe the dynamic compressive deformation of frozen soil. The proposed model is constructed by referring to the debonding damage theory of composite materials, and addresses the effects of strain rate and temperature on the dynamic compressive deformation of frozen soil. The proposed model is verified through comparison of the predictions with the corresponding dynamic experimental data of frozen soil obtained from the split Hopkinson pressure bar （SHPB） tests at different high strain rates and temperatures. It is shown that the predictions agree well with the experimental results.

关键词： frozen soil dynamic micromechanical model debonding damage theory SHPB

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基于MEMS陀螺的高温随钻定向测斜仪研究

地球物理学报 2024年第4期67卷 1669-1677页

作者：杨永友底青云谢棋军马良令王京京张露任春华中国科学院深地资源装备技术工程实验室中国科学院地质与地球物理研究所北京100029 重庆大学光电工程学院重庆400044

针对油气井测量时所面临的小孔径、超深井、温度范围广、温度变化率高、工作时间长等挑战,研究了基于MEMS陀螺仪的定向测斜仪,设计了MEMS陀螺定向测斜仪软硬件系统.为确保该环境下的测量精度提出了一种动态温度补偿方案,并采用基于小波... 详细信息

针对油气井测量时所面临的小孔径、超深井、温度范围广、温度变化率高、工作时间长等挑战,研究了基于MEMS陀螺仪的定向测斜仪,设计了MEMS陀螺定向测斜仪软硬件系统.为确保该环境下的测量精度提出了一种动态温度补偿方案,并采用基于小波滤波多尺度分析的方法对动态温变环境下陀螺输出信号进行去噪滤波处理,以实现定向测斜仪系统的测量精度.论文给出了定向测斜仪硬件系统方案、定向测斜算法、小波多尺度滤波算法.测试结果表明:该系统在常温和动态温变环境下井斜方位角精度优于±2.,井斜角精度优于±0.1°,工作温度最高150℃,可适应我国深层油气井勘探开发的应用场景需求.

关键词：定向测斜仪动态温变环境 MEMS陀螺零偏补偿

基于深层动态特征双流网络的高效行为识别算法

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计算机应用与软件 2024年第9期41卷 175-181,189页

作者：高庆吉徐达罗其俊邢志伟中国民航大学机器人研究所天津300300

为了更高效地获得视频中的行为信息,提出一种结合时域卷积与双流卷积网络的人体行为识别算法。利用多层时域卷积从视频获取动态信息,得到二维的深层动态特征;构建双流卷积网络并采用深层动态特征代替光流特征作为运动信息流的输入;加权... 详细信息

为了更高效地获得视频中的行为信息,提出一种结合时域卷积与双流卷积网络的人体行为识别算法。利用多层时域卷积从视频获取动态信息,得到二维的深层动态特征;构建双流卷积网络并采用深层动态特征代替光流特征作为运动信息流的输入;加权融合双流结果,获得对行为的判定。在公开数据集UCF101、HMDB51与NTU-RGBD-60测试,最高准确率为94.2.、70.9%与89.1%(跨对象实验)。当与经典算法ECO(Efficient Convolutional Network)和TSM(Temporal Shift Module)准确率相近时,平均并行速度分别提高2.1倍和3.6倍。所研究算法提高了计算效率,更具有实用性。

关键词：计算机视觉行为识别双流卷积网络三维卷积

An adaptive integration surface for predicting transonic rotor noise in hovering and forward flights

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Chinese Journal of Aeronautics 2019年第9期32卷 2047-2058页

作者： Siyu CHEN qijun ZHAO Yiyang MA National Key Laboratory of Rotorcraft Aeromechanics Nanjing University of Aeronautics and Astronautics

In this paper, a new permeable adaptive integration surface is developed in order to evaluate transonic rotor noise in accordance with FW-H_pds equations(Ffowcs Williams-Hawkings equations with penetrable data surface). Firstly, a nonlinear near-field solution is computed on the basis of Navier-Stokes equations, which is developed on moving-embedded grid *** solution calculated through the present CFD method is used as the input for acoustic calculations by FW-H_pds equations. Then, two criteria for constructing integration surfaces are established based on the analysis of the quadrupole source strength and the nonlinear characteristic.A new surface is determined adaptively by the pressure gradient or density in a given flowfield,eschewing the uncertainties associated with determining cylinder-shaped integration surfaces. For varying hover cases, transonic noises are simulated with new integration surfaces for a UH-1 model rotor. Furthermore, numerical results of the new integration surface derived from the density perturbation value conform better to experimental data than results derived from the pressure ***, the integration surface given by jrqj being 0.1, which is an applicable criterion obtained from hover cases, is used to predict transonic rotor noise in forward flight. The computational accuracy of the new integration surface method has been validated in predicting transonic rotor noise of an AH-1 model rotor at different advance ratios.

关键词： FW-H_pds equations Integration surface Navier–Stokes equations Rotor Transonic rotor noise

长三角地区医疗卫生资源供给的时空演化特征及其影响因素

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浙江大学学报（理学版） 2024年第1期51卷 76-89页

作者：陈玉娟王志斌周启俊瞿建平陈加正浙江工业大学设计与建筑学院浙江杭州310014 浙江工业大学工程设计集团有限公司浙江杭州310014

在健康中国与长三角区域一体化发展国家战略的目标驱使下,医疗卫生资源供给能力日渐成为区域公共设施均等化发展的重要指标,新型冠状病毒肺炎疫情等突发公共卫生事件对地区医疗卫生资源供给能力提出了更高的要求。为辨明长三角地区医疗... 详细信息

在健康中国与长三角区域一体化发展国家战略的目标驱使下,医疗卫生资源供给能力日渐成为区域公共设施均等化发展的重要指标,新型冠状病毒肺炎疫情等突发公共卫生事件对地区医疗卫生资源供给能力提出了更高的要求。为辨明长三角地区医疗卫生资源供给的发展特征与影响因素,构建了以时间演变、空间分异与因子探究为主的分析结构,采用泰尔指数、空间自相关、多尺度地理加权回归等方法,研究了2.01—2.19年长三角地区41个城市医疗卫生资源供给的区域差异与影响因素。结果表明,研究期内长三角地区医疗卫生资源增长迅速,区域均衡性提高;总体格局与长三角“Z”字形空间结构相吻合;医疗卫生资源供给的影响因素涵盖社会、经济与政治3个维度,且作用强度存在空间异质性。在此基础上,提出了促进长三角地区医疗服务一体化发展的对策及建议。

关键词：医疗卫生资源区域差异多尺度地理加权回归长三角地区

Parametric analyses on dynamic stall control of rotor airfoil via synthetic jet

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Chinese Journal of Aeronautics 2017年第6期30卷 1818-1834页

作者： qijun ZHAO Yiyang MA Guoqing ZHAO National Key Laboratory of Science and Technology on Rotorcraft Aeromechanics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

The effects of synthetic jet control on unsteady dynamic stall over rotor airfoil are investigated numerically. A moving-embedded grid method and an Unsteady Reynolds Averaged Navier-Stokes（URANS） solver coupled with k-x Shear Stress Transport（SST） turbulence model are established for predicting the complex flowfields of oscillatory airfoil under jet control. Additionally, a velocity boundary condition modeled by sinusoidal function has been developed to fulfill the perturbation effect of periodic jet. The validity of present CFD method is evaluated by comparisons of the calculated results of baseline dynamic stall case for rotor airfoil and jet control case for VR-7 B airfoil with experimental data. Then, parametric analyses are conducted emphatically for an OA2.2.rotor airfoil to investigate the effects of jet control parameters（jet location, dimensionless frequency, momentum coefficient, jet angle, jet type and dual-jet） on dynamic stall characteristics of rotor airfoil. It is demonstrated by the calculated results that efficiency of jet control could be improved with specific momentum coefficient and jet angle when the jet is located near separation point of rotor airfoil. Furthermore, the dual-jet could improve control efficiency more obviously on dynamic stall of rotor airfoil with respect to the unique jet, and the influence laws of dual-jet＇s angles and momentum coefficients on control effects are similar to those of the unique jet. Finally,unsteady aerodynamic characteristics of rotor via synthetic jet which is located on the upper surface of rotor blade in forward flight are calculated, and as a result, the aerodynamic characteristics of rotor are improved compared with the baseline. The results indicate that synthetic jet has the capability in improving aerodynamic characteristics of rotor.

关键词： Airfoil Dynamic stall characteristics:Flow control Moving-embedded gridmethodology Navier-Stokes equations Parametric analyses Rotor Synthetic jet