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Experimental study on shock interaction control of double wedge in high-enthalpy hypersonic flow subject to plasma synthetic jet

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Chinese Journal of Aeronautics 2024年第4期37卷 151-165页

作者： Xuzhen XIE Qiang LIU Yan ZHOU zhenbing LUO Wei XIE Guanghui BAI Kai LUO qiu WANG Jianjun WU College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China China Academy of Launch Vehicle Technology Beijing 100076China Institute of Mechanics Chinese Academy of SciencesBeijing 100190China

The hypersonic shock-shock interaction flow field at double-wedge geometries controlled by plasma synthetic jet actuator is experimentally studied in a Ma = 8 high-enthalpy shock tunnel with the purpose of exploring a novel technique for reducing surface heat flux in a real flight environment. The results demonstrate that increasing the discharge energy is advantageous in eliminating the shock wave, shifting the shock wave interaction point, and shortening the control response time. The oblique shock wave can be completely removed when the actuator's discharge energy grows from 0.4 J to 11.5 J, and the displacement of the shock wave interaction point increases by 124.56%, while the controlled response time is shortened by 30 μs. Besides, the reduction in diameter of the jet exit is firstly proved to have a negative impact on energy deposition in a working environment with incoming flow, which reduces the discharge energy and hence decreases the control effect. The shock wave control response time lengthens when the jet exits away from the second wedge. Along with comparing the change in wall heat flux at the second wedge over time, the control effect of plasma synthetic jet actuator with and without inflation is also analyzed. When plasma synthetic jet works in inflatable mode, both the ability to eliminate shock waves and the shifting effect of the shock wave interaction point are increased significantly, and the wall heat flux is also reduced.

关键词： Hypersonic flow High-enthalpy flow Plasma synthetic jet Shock wave Flow control

Iterated Unscented Kalman Filter for Spacecraft Attitude Estimation

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Iterated Unscented Kalman Filter for Spacecraft Attitude Est...

Precipitation of High Mg-Calcite and Protodolomite Using Dead Biomass of Aerobic Halophilic Bacteria

第37届中国控制会议

作者： Huaming Qian zhenbing qiu College of Automation Harbin Engineering University

In this paper, an iterated unscented quaternion estimator for spacecraft attitude estimation is proposed. A step length-varying iteration technique is incorporated into the unscented quaternion estimator and the corresponding termination condition is introduced to control the number of iterations and reduce the computational burden. The reference quaternion in the measurement update is redefined by the developed iteration technique. Simulation results demonstrate the superiority of the proposed new algorithm in comparison with the multiplicative extended Kalman filter, norm constraint Kalman filter and the unscented quaternion estimator under large initialization condition errors. It also shows that the proposed algorithm exhibits a faster convergence rate.

关键词： unscented quaternion estimator attitude estimation iteration technique reference quaternion

来源： cnki会议评论

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Journal of Earth Science 2023年第2期34卷 456-466页

作者： Qigao Fan Deng Liu Dominic Papineau Xuan qiu Hongmei Wang zhenbing She Linduo Zhao State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan 430078China School of Environmental Studies China University of GeosciencesWuhan 430078China London Centre for Nanotechnology University College London and Birkbeck College LondonLondon 17-19UK Department of Earth Sciences University College LondonLondon WC1E 6BTUK Center for Planetary Sciences University College LondonLondon WC1E 6BTUK Illinois Sustainable Technology Center Prairie Research InstituteUniversity of Illinois at Urbana-ChampaignChampaign 61820USA

The microbial dolomite model has been used to interpret the origin of sedimentary *** this model,the formation of low-temperature protodolomite,an important precursor to sedimentary dolomite,can be facilitated either by actively metabolizing cells of anaerobic microbes and aerobic halophilic archaea or by their inactive *** halophilic bacteria are widely distributed in(proto-)dolomite-depositing evaporitic environments and their biomass might serve as a template for the crystallization of *** test this hypothesis,carbonation experiments were conducted using dead biomass of an aerobic halophilic bacterium(Exiguobacterium *** JBHLT-3).Our results show that dead biomass of JBHLT-3 can accelerate Mg2+uptake in carbonate mineral *** addition,the amount of Mg incorporated into Ca-Mg carbonates is proportional to the concentration of *** Mg-calcite is produced with 0.25 or 0.5 g/L biomass,whereas protodolomite forms with 1 g/L *** is confirmed by the main Raman peak of Ca-Mg carbonates,which shifts towards higher wavenumbers with increased Mg *** cells and their imprints are preserved on the surface of high Mg-calcite and ***,this study furthers our understanding of the dolomitization within buried and dead microbial mats,which provides useful insights into the origin of ancient dolomite.

关键词： protodolomite high Mg-calcite Mg-hydration effect microbial dead biomass biosignature paleobiology

Monitoring the delicate operations of surgical robots via ultra-sensitive ionic electronic skin

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National Science Review 2022年第12期9卷 163-176页

作者： Danyang Wei Jiajie Guo Yuqi qiu Shaoyu Liu Jiangyan Mao Yutian Liu zhenbing Chen Hao Wu Zhouping Yin State Key Laboratory of Digital Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and Technology Department of Hand Surgery Union Hospital Tongji Medical CollegeHuazhong University of Science and Technology

The arrival of surgical robots in high-end medical equipment is a landmark,and the realization of tactile sensation a major challenge in this important cutting-edge research *** to address this issue,we present ultra-sensitive ionic electronic skin in the form of flexible capacitive pressure sensors,which incorporate multistage bionic microstructures in ion gels for the purpose of monitoring the delicate operations of surgical ***,the ionic skin exhibits an ultra-high sensitivity of 9484.3 kPa-1(<15 kPa),and the sensitivity remains higher than 235 kPa-1in the wide range of 15-155 *** device has also achieved a detection limit as low as 0.12 Pa or,equivalently,0.31 mg,fast response within 24 ms,and high robustness(loading/unloading for 5000 cycles without fatigue).The sensor facilitates the challenging task of tele-operated robotic threading,which exceeds the human tactile perception limit when threading a *** have also confirmed that ionic skin can be used in robot-assisted invasive surgery,such as incision/resection of tissues and suturing of wounds,providing tactile information to surgeons to improve operation success *** flexible ionic skin is capable of conforming to the various shapes of robotic manipulators,thus has great promise for applications in robotic dexterous manipulation,prosthetics and human-machine interfaces.

关键词： surgical robots delicate operations ultra-sensitive ionic electronic skin tactile sensing

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变电站电气设备双通道图像在线监测方法

电力系统自动化 2008年第10期32卷 76-79页

作者：赵振兵高强苑津莎闫龙邱巍巍华北电力大学电气与电子工程学院河北省保定市071003 厦门电业局福建省厦门市361004

为了实现对电气设备的远程、实时、在线的红外温度图像和可见光图像监测,设计并实现了双通道系统。给出了以红外传感器和可见光电荷耦合器件(CCD)为核心器件的系统总体方案,描述了变电站端监测系统的具体硬件组成和工作原理,采用面向对... 详细信息

为了实现对电气设备的远程、实时、在线的红外温度图像和可见光图像监测,设计并实现了双通道系统。给出了以红外传感器和可见光电荷耦合器件(CCD)为核心器件的系统总体方案,描述了变电站端监测系统的具体硬件组成和工作原理,采用面向对象的思想和模块化程序设计开发了系统的服务器端软件及客户端软件,研究了基于傅里叶变换的红外与可见光图像的自动匹配方法及工程上易实现的手动匹配方法。该系统实现了对电气设备的双通道图像的远程、实时、在线监测,可及时发现设备外部问题以及过热、环境问题。现场运行表明,该系统稳定可靠、效果良好。

关键词：电气设备变电站在线监测图像匹配

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沁水盆地寺河煤矿煤岩吸附甲烷规律实验研究

石油实验地质 2014年第5期36卷 656-658页

作者：张振兵邱小龙袁月琴李向峰郝琦王军贵州省地质矿产开发局一一三地质大队贵州六盘水553001

煤储层具有大量的裂隙和孔隙，使煤岩具有很大的比表面积，为煤中甲烷的吸附提供了必要条件。采用自主研发的煤层气吸附装置，通过对沁水盆地寺河煤矿不同粒径煤粉的吸附性模拟实验，总结了不同粒径煤粉在吸附甲烷12 h内的吸附规律，计... 详细信息

煤储层具有大量的裂隙和孔隙，使煤岩具有很大的比表面积，为煤中甲烷的吸附提供了必要条件。采用自主研发的煤层气吸附装置，通过对沁水盆地寺河煤矿不同粒径煤粉的吸附性模拟实验，总结了不同粒径煤粉在吸附甲烷12 h内的吸附规律，计算出其中吸附气量，研究了吸附速率、吸附量的变化规律。研究认为：吸附的前10 min，吸附量占总吸附量的40％～60％，煤粉粒径越小，所占的比例越大，吸附越快；不同粒径煤粉的吸附量为15．1～29．1 mL/g，煤粉粒径越小，单位质量煤粉吸附量越大。通过对煤岩吸附规律的深入研究，为沁水盆地煤层气的勘探开发提供技术支持。

关键词：吸附速率吸附量比表面积煤岩甲烷沁水盆地

窄带成像内镜下齿状线观察评价胃食管反流病的价值

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实用临床医药杂志 2017年第17期21卷 69-71页

作者：邱伟方晓华杨振斌殷鸿夏文娟江苏省扬州市中医院脾胃病科江苏扬州225002

目的探讨窄带成像放大内镜结合齿状线形态观察评价胃食管反流病的价值。方法选取GERD组200例和对照组160例,Gred-Q评分法记录症状,通过窄带成像放大内镜观察齿状线形态、食管微血管表现,探讨Gred-Q评分法、齿状线形态、食管微血管表现... 详细信息

目的探讨窄带成像放大内镜结合齿状线形态观察评价胃食管反流病的价值。方法选取GERD组200例和对照组160例,Gred-Q评分法记录症状,通过窄带成像放大内镜观察齿状线形态、食管微血管表现,探讨Gred-Q评分法、齿状线形态、食管微血管表现的相关性及与胃食管反流病的关系。结果 GRED组患者NBI微血管异常阳性率显著高于对照组(P<0.05)。GRED组患者齿状线形态异常率显著高于对照组(P<0.05)。NBI微血管表现与Gerd-Q评分、齿状线形态与Gerd-Q评分、窄带成像内镜下微血管表现与齿状线形态均呈正相关(r=0.780、0.803、0.586,P<0.01)。结论窄带成像放大内镜对胃食管反流病的诊断有重要临床价值。

关键词：窄带成像放大内镜齿状线形态食管微血管胃食管反流病