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Journal of Systems Engineering and Electronics 2008年第3期19卷 419-426页

作者： Bian hailong chen Guangju CAT Lab School of Automation Engineering Univ. of Electronic Science and Technology Chengdu 610054 P. R. China

To eliminate the aliasing that appeared during the measurement of multi-components nonstationary signals, a novel kind of anti-aliasing algorithm based on the short time Fourier transform （STFT） is brought forward. First the physical essence of aliasing that occurs is analyzed; second the interpolation algorithm model is setup based on the Hamming window; then the fast implementation of the algorithm using the Newton iteration method is given. Using the numerical simulation the feasibility of algorithm is validated. Finally, the electrical circuit experiment shows the practicality of the algorithm in the electrical engineering.

关键词： nonstationary signal interpolation anti-aliasing short time Fourier transform (STFT) iterative algorithm.

Layered metastructure containing freely-designed local resonators for wave attenuation

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Defence Technology（防务技术） 2024年第2期32卷 23-31页

作者： Yu Li Huguang He Jiang Feng hailong chen Fengnian Jin Hualin Fan State Key Laboratory for Disaster Prevention&Mitigation of Explosion&Impact Army Engineering University of PLANanjing 210007China Rocket Force University of Engineering Xi'an 710025China Henan International Joint Laboratory of Dynamics of Impact and Disaster of Engineering Structures Department of Civil EngineeringNanyang Institute of TechnologyNanyang 473004China Guangxi Key Laboratory of Disaster Prevention and Engineering Safety and Key Laboratory of Disaster Prevention and Structural Safety of Ministry of EducationCollege of Civil Engineering and ArchitectureGuangxi UniversityNanning 530004China Research Center of Lightweight Structures and Intelligent Manufacturing State Key Laboratory of Mechanics and Control of Mechanical StructuresNanjing University of Aeronautics and AstronauticsNanjing 210016China

Combining periodic layered structure with three-dimensional cylindrical local resonators,a hybrid metastructure with improved wave isolation ability was designed and investigated through theoretical and numerical *** metastructure is composed of periodic rubber layers and concrete layers embedded with three-dimensional resonators,which can be freely designed with multi local resonant frequencies to attenuate vibrations at required frequencies and widen the attenuation *** metastructure can also effectively attenuate seismic *** with layered rubber-based structures,the metastructure has more excellent wave attenuation effects with greater attenuation and wider bandgap.

关键词： Layered metastructure Local resonator Wave attenuation

Fuzzy Comprehensive Analysis of Static Mixers Used for Selective Catalytic Reduction in Diesel Engines

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Fluid Dynamics & Materials Processing 2024年第11期20卷 2459-2473页

作者： Xin Luan Guoqing Su hailong chen Min Kuang Department of Electrical and Mechanical Management China Coast Guard AcademyNingbo315801China Ningbo Key Laboratory of Green Shipping Technology Faculty of Maritime and TransportationNingbo UniversityNingbo315211China

The proper selection of a relevant mixer generally requires an effective assessment of several models against theapplication requirements. This is a complex task, as traditional evaluation methods generally focus only on a single aspect of performance, such as pressure loss, mixing characteristics, or heat transfer. This study assesses aurea-based selective catalytic reduction (SCR) system installed on a ship, where the installation space is limitedand the distance between the urea aqueous solution injection position and the reactor is low;therefore, the staticmixer installed in this pipeline has special performance requirements. In particular, four evaluation indices areused in this study: The B value, C value, pressure loss correction factor (Z′), and the ratio of the required distanceto the equivalent diameter of the pipe (LV/D) when the velocity field after the mixer attains uniformity. Six typesof static mixers were simulated with varying concentrations, flow speeds, and positions. A fuzzy comprehensiveevaluation method was introduced to evaluate and compare the related advantages and disadvantages. The resultsshowed that 1) mixing performance was related to the shape of the mixer and had no direct relationship with flowvelocity. 2) For the same mixer position, the lower the urea concentration, the greater the difficulty of evenly mixing the solution. 3) At a constant urea concentration, the mixing performance improved when the mixer was closer to the injection inlet. 4) The installation of a GK mixer in the SCR system of a 9L20C diesel engine was best.

关键词： Static mixer fuzzy comprehensive evaluation coefficient of variation mixing performance

Goal Programming for Stable Mode Transition in Tandem Turbo-ramjet Engines

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Chinese Journal of Aeronautics 2009年第5期22卷 486-492页

作者： chen Min Tang hailong Zhu Zhili School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100191 China

This article, in order to guarantee the stable mode transition in tandem turbo-ramjet engines, investigates the multi-objective and multi-variable goal programming algorithm. First, it introduces the structural features of the variable cycle turbo-ramjet engines, the principles of selecting the mode transition operation point and the design parameters, and the characteristics of the turbofan mode and the ramjet mode. Second, a component-based variable cycle turbo-ramjet engine model is developed to simulate the mode transition process. Third, the Newton-Raphson algorithm is used to solve the multi-variable and multi-objective optimization problem. The results show that with the maximum residua of only 0.06%, this algorithm has an acceptable convergence that meets the predetermined goals. Finally, the simulation shows that the stable turbo-ramjet mode transition could be realized with the mode transition control law developed by the algorithm.

关键词： propulsion transition goal programming algorithm turbine-based combine cycle engine turbofan engine ramjetengine hypersonic

Bi_2Se_3/C Nanocomposite as a New Sodium-Ion Battery Anode Material

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Nano-Micro Letters 2018年第3期10卷 135-143页

作者： Lixin Xie Ze Yang Jingying Sun Haiqing Zhou Xiaowei Chi hailong chen ANDy X.Li Yan Yao Shuo chen Department of Physics and TcSUH University of Houston Department of Electrical and Computer Engineering and Materials Science and Engineering Program University of Houston The Woodruff School of Mechanical Engineering Georgia Institute of Technology Clements High School

Bi_2Se_3 was studied as a novel sodium-ion battery anode material because of its high theoretical capacity and high intrinsic conductivity. Integrated with carbon,Bi_2Se_3/C composite shows excellent cyclic performance and rate capability. For instance, the Bi_2Se_3/C anode delivers an initial capacity of 527 mAh g^(-10) at 0.1 A g^(-1) and maintains 89% of this capacity over 100 cycles. The phase change and sodium storage mechanism are also carefully investigated.

关键词： Bi2Se3 Sodium-ion battery High-energy ball milling Sodium storage mechanism

Spatial and temporal variations in cyanobacteria and microcystins in Aha Reservoir,Southwest China

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Journal of Oceanology and Limnology 2018年第4期36卷 1126-1131页

作者： HAN Mengshu LI Qiuhua chen hailong XIAO Jing JIANG Fan Key Laboratory for Information System of Mountainous Area and Protection of Ecological Environment of Guizhou Province Guizhou Normal University Guiyang 550001China

Toxic cyanobacteria(TCB) are well-known worldwide for their adverse impacts on humans. Species compositions and seasonal variations of TCB in reservoirs depend on interactions between physical and chemical factors. This study was conducted to evaluate the water quality in the Aha Reservoir, Southwest China, focusing on cyanobacteria and cyanotoxins. Water samples were collected weekly or biweekly from May to September of 2015 and used to delineate temporal variations in density and distribution of toxic cyanobacteria and cyanotoxins in the reservoir. Toxic cyanobacteria identified consisted of Aphanizomenon flos-aquae, Pseudanabaena limnetica, Cylindrospermopsis sp., and Microcystis sp., with Aphanizomenon flos-aquae and Pseudanabaena limnetica being the most common and significant toxic genera. The total biomass of cyanobacteria was 17.0 mg/L. Identification and quantification of microcystin variants were conducted by high performance liquid chromatography(HPLC) using a system equipped with a photodiode array detector. Microcystin levels were between 0–3.0 μg/L, MC-RR was around 0–3.0 μg/L and MC-LR was approximately 0–0.9 μg/L. Overall, the results of this study indicate that the investigated reservoirs should be monitored regularly to minimize potential health risks to the human population.

关键词： Cyanobacteria Aphanizomenonflos-aquae Microcystin-LR Microcystin-RR Aha Reservoir

Mild Breakthrough Infection in a Healthcare Professional Working in the Isolation Area of a Hospital Designated for Treating COVID-19 Patients—Shaanxi Province,China,March,2021

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China CDC weekly 2021年第19期3卷 397-400页

作者： Chaofeng Ma Songtao Xu Yecheng Yao Pengbo Yu You Xu Rui Wu hailong chen Xiaoping Dong Xi’an Center for Diseases Control and Prevention Xi’anShaanxiChina State Key Laboratory for Infectious Disease Prevention and Control Collaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesNational Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina National Institute for Nutrition and Health Chinese Center for Disease Control and PreventionBeijingChina Shaanxi Center for Diseases Control and Prevention Xi’anShaanxiChina Xi’an No.8 Hospital Xi’anShaanxiChina Center for Global Public Health Chinese Center for Disease Control and PreventionBeijingChina Center for Biosafety Mega-Science Chinese Academy of SciencesWuhanHubeiChina China Academy of Chinese Medical Sciences BeijingChina.

Summary What is already known about this topic?Healthcare workers are at high risk of acquiring COVID-19 from occupational exposure to COVID-19 virus during their daily medical service *** infection prevention and control measures and adequate personal protective equipment(PPE)are essential to reduce the risk of hospital-acquired COVID-19.

关键词： prevention protective COV

卡维地洛联合沙库巴曲缬沙坦治疗慢性心力衰竭的临床观察

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锦州医科大学学报 2019年第1期40卷 22-24页

作者：陈海龙惠州市第一人民医院评审评价办公室广东惠州516008

目的探讨卡维地洛联合沙库巴曲缬沙坦治疗慢性心力衰竭的临床效果。方法选取2016年1月至2018年6月在我院接受治疗的慢性心力衰竭患者80例作为研究对象,随机分为对照组和观察组,每组各40例。对照组采用卡维地洛联合缬沙坦治疗,观察组采... 详细信息

目的探讨卡维地洛联合沙库巴曲缬沙坦治疗慢性心力衰竭的临床效果。方法选取2016年1月至2018年6月在我院接受治疗的慢性心力衰竭患者80例作为研究对象,随机分为对照组和观察组,每组各40例。对照组采用卡维地洛联合缬沙坦治疗,观察组采用卡维地洛联合沙库巴曲缬沙坦治疗,比较两组的临床治疗效果和治疗前后的指标情况。结果在临床治疗总有效率方面,对照组和观察组分别为80. 0%、95. 0%,观察组要明显高于对照组,差异有统计学意义(P<0. 05);在LVEF、心率等治疗指标方面,观察组治疗前后差异明显大于对照组,差异有统计学意义(P<0. 05);在LVEDD、LVESD等治疗指标方面,观察组治疗前后差值明显大于对照组(P<0. 05)。结论慢性心力衰竭的治疗中,将卡维地洛和沙库巴曲缬沙坦联合用药治疗效果明显,可以促进患者症状的改善和健康的恢复。

关键词：卡维地洛沙库巴曲缬沙坦慢性心力衰竭效果

Effects of Thirty Days Isolation on Attention Networks: A Behavioral and Event-related Potential Study

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Neuroscience Bulletin 2024年第1期40卷 127-132页

作者： Jingda Feng Bin Wu Ziqing Cao hailong chen Tianjun Lan Haibo Qin Yusheng Shi Weifen Huang Yinghui Li Department of Aerospace Science and Technology Space Engineering UniversityBeijing 101400China China Astronaut Research and Training Center Beijing 100094China State Key Laboratory of Space Medicine Fundamentals and Application China Astronaut Research and Training CenterBeijing 100094China School of Psychology Shaanxi Normal UniversityXi'an 710000China

Kear Editor,Individuals in isolated,confined,and extreme environments,such as astronauts,researchers wintering over Antarctica,submarine soldiers,and participants in simulated isolation environment experiments,commonly report difficulty in focusing their attention[1,2].However,current experimental findings from studies conducted in such environments are insufficient to fully support these self-reports of reduced *** attention-demanding tasks such as simple reaction time(RT)tasks and dual tasks,including primary pursuit tracking and secondary RT,were not affected in space flight experiments[2,3].

关键词： environments submarine winter

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集束型玻璃纤维混凝土轴拉、弯曲和断裂性能

哈尔滨工程大学学报 2019年第5期40卷 993-999页

作者：邓宗才陈海龙北京工业大学城市与工程防灾减灾省部共建教育部重点实验室北京100124

为掌握不同掺率耐碱集束型玻璃纤维混凝土的力学韧性,本文对不同体积掺率的耐碱集束型玻璃纤维混凝土和钢纤维及粗聚烯烃纤维混凝土进行了轴拉、四点弯曲韧性和三点切口梁断裂试验。分析了纤维掺率对耐碱集束型玻璃纤维混凝土力学性能... 详细信息

为掌握不同掺率耐碱集束型玻璃纤维混凝土的力学韧性,本文对不同体积掺率的耐碱集束型玻璃纤维混凝土和钢纤维及粗聚烯烃纤维混凝土进行了轴拉、四点弯曲韧性和三点切口梁断裂试验。分析了纤维掺率对耐碱集束型玻璃纤维混凝土力学性能的影响规律,并和同体积掺率的钢纤维和粗聚烯烃纤维混凝土进行了比较。试验表明:耐碱集束型玻璃纤维混凝土轴拉性能优于同体积掺率的粗聚烯烃纤维混凝土,轴拉强度和极限拉应变均略高于同体积掺率的钢纤维混凝土;耐碱集束型玻璃纤维体积掺率为0. 75%时,弯曲韧性值和峰值强度比素混凝土分别提高了191. 73%和11. 47%,断裂韧度和断裂能比素混凝土分别提高了28. 16%和268. 69%,该掺率下耐碱集束型玻璃纤维混凝土弯曲韧性指标和断裂力学指标增幅较大。

关键词：耐碱集束型玻璃纤维轴拉性能弯曲韧性断裂性能体积掺率钢纤维聚烯烃纤维纤维混凝土