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Journal of Hydrodynamics 2023年第2期35卷 314-329页

作者： Bo-jie Hong chang-li Hu Zhi-ying Wang Hao-jie Xing School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing210094China Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of MechanicsChinese Academy of SciencesBeijing100190China

The objective of this work is to reveal the effect of a passive control method called wedge-type cavitating-bubble generator(WCG)on the cloud cavitation dynamics of National Advisory Committee for Aeronautics(NACA)66 *** simulations are performed using the Partially-averaged Navier-Stokes(PANS)method coupled with the Zwart cavitation *** proper orthogonal decomposition(POD)method is applied to extract the dominant flow *** results show that the WCG can induce the attached cavity to occur just behind the WCG instead of the hydrofoil leading *** the periodical time-evolution process of the unsteady cavity,it is found that the attached cavity with a larger scale around the hydrofoil with WCG has a rougher surface,accompanied with more shedding behaviors of small *** is further illustrated by the POD modes,that is,the mode 1 and modes 2–4 present the large and small cavity vortex structures ***,the dominant frequencies of 50 Hz,47.5 Hz are given by the POD method respectively for the hydrofoils without and with WCG,which is in good agreement with that of FFT *** addition,the correlation distribution of POD modal coefficients shows that the WCG can strengthen the vortex energy as well as the turbulence intensity.

关键词： Cavitating-bubble generator proper orthogonal decomposition(POD) attached cavity vortex structures

A high-capacity cathode for rechargeable K-metal battery based on reversible superoxide-peroxide conversion

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National Science Review 2021年第10期8卷 33-41页

作者： Yu Qiao Han deng Zhi chang Xin Cao Huijun Yang Haoshen Zhou Energy Technology Research Institute National Institute of Advanced Industrial Science and Technology (AIST) Center of Energy Storage Materials &Technology College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional MaterialsNational Laboratory of Solid State Microstructures and Collaborative Innovation Center of Advanced MicrostructuresNanjing University

As a promising low-cost energy storage device, the development of a rechargeable potassium-ion battery(KIB) is severely hindered by the limited capacity of cathode candidates. Regarded as an attractive capacity-boosting strategy, triggering the O-related anionic redox activity has not been achieved within a sealed KIB system. Herein, in contrast to the typical gaseous open K-Obattery(O/KOredox), we originally realize the reversible superoxide/peroxide(KO/KO) interconversion on a KO-based cathode. Controlled within a sealed cell environment, the irreversible Oevolution and electrolyte decomposition(induced by superoxide anion(O~-) formation) are effectively restrained. Rationally controlling the reversible depth-of-charge at 300 m Ah/g(based on the mass of KO), no obvious cell degradation can be observed during 900 cycles. Moreover, benefitting from electrolyte modification, the KO-based cathode is coupled with a limited amount of K-metal anode(merely 2.5 times excess),harvesting a K-metal full-cell with high energy efficiency(～90%) and long-term cycling stability(over 300 cycles).

关键词： electrochemistry rechargeable battery beyond Li-ion battery long-term cycle life high capacity cathode

Machine learning enabled film pressure sensor to identify surface contacts:An application in surface transmission of infectious disease

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Building Simulation 2024年第6期17卷 1023-1036页

作者： Baotian chang Jianchao Zhang Yingying Geng Jiarui Li Doudou Miao Nan Zhang Beijing Key Laboratory of Green Built Environment and Energy Efficient Technology Beijing University of TechnologyBeijing100124China

The global prevalence of infectious diseases has emerged as a significant challenge in recent *** transmission is a potential transmission route of most gastrointestinal and respiratory infectious diseases,which is related to surface touch *** observation,the traditional method of surface touching data collection,is characterized by limited accuracy and high labor *** this work,we proposed a methodology based on machine learning technologies aimed at obtaining high-accuracy and low-labor-cost surface touch behavioral data by means of sensor-based contact *** touch sensing device,primarily utilizing a film pressure sensor and Arduino board,is designed to automatically detect and collect surface contact data,encompassing pressure,duration and *** make certain the surface touch behavior and to describe the behavioral data more accurately,six classification algorithms(*** Vector Machine and Random Forest)have been trained and tested on an experimentally available dataset containing more than 500 surface *** classification results reported the accuracy of above 85%for all the six classifiers and indicated that Random Forest performed best in identifying surface touch behaviors,with 91.8%accuracy,91.9%precision and 0.98 *** study conclusively demonstrated the feasibility of identifying surface touch behaviors through film pressure sensor-based data,offering robust support for the calculation of viral load and exposure risk associated with surface transmission.

关键词： surface transmission touch behavior film pressure sensor random forest infectious disease

Wind Tunnel Experiments and Numerical Study on Performance Characteristics of an H-type Vertical Axis Wind Turbine in the Spanwise Direction

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Journal of Thermal Science 2021年第3期30卷 758-771页

作者： ZHANG Yanfeng LI Qing’an ZHU Xinyu SONG Xiaowen CAI chang GUO Zhiping College of Science Inner Mongolia University of TechnologyHohhot 010051China Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China College of Mechanical Engineering Inner Mongolia University of TechnologyHohhot 010051China

The aerodynamic forces and vortex characteristics of an H-type Vertical Axis Wind Turbine(VAWT)become complicated because of dynamic stall,particularly in the three-dimensional impact on the blade spanwise *** study focused on the evaluation of the aerodynamic performance and vortex characteristics of an H-type VAWT in the spanwise direction by numerical simulations and wind tunnel *** acting on the blade surface was obtained from multiport pressure measurement devices by wind ***,the vortex field around different blade sections was investigated through numerical *** stall behavior was analysed by comparing the results of numerical simulations and *** a result,the tangential force of single blade was mainly contributed at the chordwise position of x/c≤0.4 c and the power of single blade was mainly contributed at the azimuthal angle range of 60°≤θ≤150°in the blade section position region of 0≤z/(H/2)≤*** the section position of z/(H/2)=0.5,the initial flow separation was found at the suction side and progressed forward to the leading *** the increase of the tip speed ratios,the decreasing position of the averaged local power coefficient of each section was closer to the middle section of z/(H/2)=0,and the attenuation speed became *** power coefficient reductions at the blade section position of z/(H/2)=0.9 were 38.29%,46.78%and 56.42%when the tip speed ratios were 1.38,2.19 and 2.58,*** results of this study provided a better understanding of the development of the performance characteristics and vortex characteristics of H-type VAWT.

关键词： VAWT wind tunnel experiments CFD spanwise direction pressure distribution power coefficient

H2FPEF评分对非射血分数降低型心力衰竭患者预后的预测价值

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中国心血管病研究 2025年第1期23卷 47-51页

作者：孙晶孟昌白莹郑山海应急总医院重症医学科北京市100028

目的探讨H2FPEF评分对非射血分数降低型心力衰竭(non-HFrEF)患者临床预后的预测价值。方法本研究为前瞻性、单中心、观察性研究,选取2021年2月至2022年2月在应急总医院治疗的non-HFrEF患者,根据H2FPEF评分分为低分组(0~1分)、中间组(... 详细信息

目的探讨H2FPEF评分对非射血分数降低型心力衰竭(non-HFrEF)患者临床预后的预测价值。方法本研究为前瞻性、单中心、观察性研究,选取2021年2月至2022年2月在应急总医院治疗的non-HFrEF患者,根据H2FPEF评分分为低分组(0~1分)、中间组(2~5分)和高分组(6~9分),随访2年,研究主要终点为全因死亡率,次要终点包括心源性死亡、再住院率、入住ICU等。结果共200例患者入组,低分组51例,中间组102例,高分组47例。全因死亡率、心源性死亡、入住ICU率、心力衰竭再住院率等在3组间比较差异均有统计学意义(P<0.01)。多因素Cox回归分析显示,高血压、心房颤动和H2FPEF评分(HR=2.251,95%CI 1.672~3.031,P<0.001)等是全因死亡的独立预测因素。受试者工作特征曲线分析显示,H2FPEF评分预测全因死亡和心力衰竭再住院发生能力较好,曲线下面积分别为0.890(P=0.001)和0.837(P=0.001),H2FPEF评分预测发生2年内全因死亡的最佳界值为4.5分,预测发生心力衰竭再住院事件的最佳界值为2.5分。结论 H2FPEF评分是预测non-HFrEF患者预后的良好工具。

关键词：非射血分数降低型心力衰竭 H2FPEF评分预后全因死亡

Coactive design of explainable agent-based task planning and deep reinforcement learning for human-UAVs teamwork

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Chinese Journal of Aeronautics 2020年第11期33卷 2930-2945页

作者： chang WANG Lizhen WU Chao YAN Zhichao WANG Han LONG Chao YU College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China College of Liberal Arts National University of Defense TechnologyChangsha 410073China School of Data and Computer Science Sun Yat-sen UniversityGuangzhou 510275China

Unmanned Aerial Vehicles(UAVs)are useful in dangerous and dynamic tasks such as search-and-rescue,forest surveillance,and anti-terrorist *** tasks can be solved better through the collaboration of multiple UAVs under human ***,it is still difficult for human to monitor,understand,predict and control the behaviors of the UAVs due to the task complexity as well as the black-box machine learning and planning algorithms being *** this paper,the coactive design method is adopted to analyze the cognitive capabilities required for the tasks and design the interdependencies among the heterogeneous teammates of UAVs or human for coherent ***,an agent-based task planner is proposed to automatically decompose a complex task into a sequence of explainable subtasks under constrains of resources,execution time,social rules and ***,a deep reinforcement learning approach is designed for the UAVs to learn optimal policies of a flocking behavior and a path planner that are easy for the human operator to understand and ***,a mixed-initiative action selection mechanism is used to evaluate the learned policies as well as the human’s *** results demonstrate the effectiveness of the proposed methods.

关键词： Coactive design deep reinforcement learning Human-robot teamwork Mixed-initiative Multi-agent system Task planning UAV

Efficient prediction of corrosion behavior in ternary Ni-based alloy systems:Theoretical calculations and experimental verification

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Journal of Materials Science & Technology 2023年第36期167卷 94-106页

作者： Xuelian Xiao Keke chang Kai Xu Ming Lou Liping Wang Qunji Xue Key Laboratory of Marine Materials and Related Technologies Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Pourbaix diagrams are calculated to describe electrochemical processes for alloys in aqueous *** the multi-component differentiation of alloy systems,the construction of Pourbaix diagrams is fac-ing challenges,especially for non-single-phase alloy *** this study,the simultaneous construction of phase diagrams and Pourbaix diagrams were implemented for predicting the evolution of the phases in the immune and passive *** CALPHAD(CALculation of PHAse Diagram)approach was used to quickly access the Gibbs free energies of various phases and the chemical potential of the elements in the phases from the thermodynamic database of the Ni-Si-Al-Y *** corrosion behavior of two typical Ni-Al-Si and Ni-Al-Y systems was *** and Y were added to Ni-based alloys to produce the solid solutions L12-Ni_(3)(Al,Si)and L12-Ni_(3)Al+Ni_(5)Y,*** showed that NiO and Al_(2)O_(3)make up the passive area of the Ni_(3)Al 1 *** introduction of SiO_(2)and Y(OH)3 in the passive region separately helped to minimize the alloys’susceptibility to ***,Si reduced the thermody-namical possibility of NiO for mation in the passive film,and the addition of Y caused extreme galvanic *** on Ni-based alloys validated the results through electrochemical *** was also discovered that the presence of Ni_(5)Y produced galvanic corrosion and that Si reduced the oxide in the passive film,causing pitting *** corrosion prediction of the quaternary alloys indicates that the solid solution of Si in Ni_(5)Y reduces the galvanic corrosion effect and the dissolution of passive *** current work demonstrates that phase diagrams and Pourbaix diagrams may be efficiently and accurately predicted using a well-constructed thermodynamic database,which has major implications for future studies on the corrosion behavior of multi-component alloys.

关键词： Pourbaix diagrams CALPHAD Ni-based alloys Passive film

Broadband absorption performance of 3D-printed polyetheretherketone-based electromagnetic wave-absorbing composites

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Chinese Journal of Aeronautics 2024年第8期37卷 547-558页

作者： Lin BAI Nan chang Meiying ZHAO Chi HOU Yi CAO Dichen LI School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Chengdu Aircraft design and Research Institute Chengdu 610091China Xi’an Key Laboratory of Advanced Structure design and Application of Aircraft Northwestern Polytechnical UniversityXi’an 710072China State Key Laboratory for Manufacturing System Engineering Xi’an Jiaotong UniversityXi’an 710054China

The rapid development of additive manufacturing technology has offered a new avenue for designing and fabricating high wave-absorbing meta *** this study,the mechanical properties and broadband absorption performance of Poly-Ether-Ether-Ketone(PEEK)–based electromagnetic wave–absorbing composite materials was *** high-performance polymer PEEK was used as the matrix,and the materials with electromagnetic wave loss,such as reduced graphene oxide,Carbonyl Iron(CI),and Flake CI(FCI),were used as *** on the theory of impedance matching,a wave-absorbing structure with a gradual impedance gradient was designed and *** test results showed that at the 2.0–18.0 GHz frequency band,the coverage rate of the effective absorption bandwidth was up to 72.0%,the average optimal reflectivity was–18.09 dB,and the wide-angle absorption range was 0°–30°.The advantages of additive manufacturing technology in designing and fabricating wave-absorbing structures are presented,demonstrating that the technology is an effective method for creating broadband absorbing structures.

关键词： Absorption performance Additive manufacturing Electromagnetic absorption PEEK composite materials Gradual structure Broadband absorption

Visualization and Analysis of the Volume Dataset for Time-Varing Electromagnetic Simulation

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Chinese Journal of Electronics 2020年第5期29卷 973-981页

作者： SHAO Jingxuan TIAN Ge HAN Jing chang Liang CAO Yi LUO Yanlin College of Artificial Intelligence Beijing Normal University Institute of Applied Physics and Computational Mathematics

The three Dimensional(3D) visualization of time-varying Electromagnetic(EM) data in antenna devices can be used to evaluate various parameters, such as the quality of beams and the power performance of antennas, for optimizing the antenna design. Compared with the single volume data, the time-varying data has characteristics of strong continuity, large scale and multi-variable. It is challenging. We proposed a real-time dynamic rendering method using Compute unified device architecture(CUDA)-based volume rendering *** designed the opacity transfer function as multiple trapezoid, which represents each energy band, and provided a fusion strategy for a horn-like surface and a EM volume model that considers the contribution of both intersection points of surface with viewing ray and sample points of the volume. We also proposed a framework for time-varying 3D EM datasets. Two assessment tests were conducted by both experts and students. Results showed that our 3D visualization method were effective.

关键词： Fusion for volume visualization 3D visualization method time-varing electromagnetic simulation transfer functions parallel architectures antennas time-varying electromagnetic data time-varying 3D EM datasets opacity transfer function strong continuity antenna design three dimensional visualization opacity electrical engineering computing compute unified device architecture-based volume CUDA Electromagnetic real-time dynamic rendering method single volume data Time-varying EM volume model time-varying data rendering (computer graphics) antenna devices 3D EM datasets data visualisation volume dataset Transfer function

老年子宫内膜癌患者miR-135a、XPO4、hTERT表达水平及临床意义

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中国老年学杂志 2025年第3期45卷 554-558页

作者：杨长香韩自旺张欣萍后爽赵正滢南阳市第一人民医院妇一科河南南阳473000 南阳市第一人民医院全科医学科河南南阳473000

目的探讨老年子宫内膜癌患者miR-135a、输出蛋白(XPO)4、人类端粒酶逆转录酶(hTERT)表达水平及临床意义。方法选取老年子宫内膜癌患者96例、子宫内膜增生患者48例,分别为子宫内膜癌组、对照组。采集空腹肘正中静脉血,逆转录法检测血清mi... 详细信息

目的探讨老年子宫内膜癌患者miR-135a、输出蛋白(XPO)4、人类端粒酶逆转录酶(hTERT)表达水平及临床意义。方法选取老年子宫内膜癌患者96例、子宫内膜增生患者48例,分别为子宫内膜癌组、对照组。采集空腹肘正中静脉血,逆转录法检测血清miR-135a、XPO4、hTERT表达水平;收集患者肿瘤浸润深度、病理分级、淋巴结转移、FIGO分期、病理类型。结果子宫内膜癌组miR-135a表达水平低于对照组,XPO4 mRNA、hTERT mRNA表达水平高于对照组,差异有统计学意义(P1/2肌层、有淋巴结转移、FIGO分期Ⅱ、Ⅲ期的老年子宫内膜癌患者miR-135a表达水平明显降低,XPO4 mRNA、hTERT mRNA表达水平明显升高(P0.7,均有一定的预测价值,且联合预测价值(AUC=0.936)高于单独预测(P<0.05)。结论老年子宫内膜癌患者miR-135a低表达,XPO4、hTERT高表达,且与病理指标和预后相关,联用对患者预后具有较高的预测价值。

关键词：子宫内膜癌 miR-135a 输出蛋白4 人类端粒酶逆转录酶