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Analysis method and experimental study of ice accumulation detection signal based on Lamb waves

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Chinese Journal of Aeronautics 2024年第8期37卷 388-403页

作者： Yanxin ZHANG Hongjian ZHANG Xian YI Binrui WU Xianlei GUAN Jianjun XIONG Key Laboratory of Icing and Anti/De-icing China Aerodynamics Research and Development CenterMianyang 621000China State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000China

A quantitative identification method for in-flight icing has the capability to significantly enhance the safety of aircraft *** guided waves have the unique advantage of detecting icing in a relatively large area,but quantitative identification of ice layers is a *** this paper,a quantitative identification method of ice accumulation based on ultrasonic guided waves is ***,a simulation model for the wave dynamics of piezoelectric coupling in three dimensions is established to analyze the propagation characteristics of Lamb waves in a structure consisting of an aluminum plate and an ice *** wavelet transform method is utilized to extract the Time of Flight(ToF)or Time of Delay(ToD)of S_(0)/B_(1) mode waves,which serves as a characteristic parameter to precisely determine and assess the level of ice ***,an experimental system is developed to evaluate the feasibility of Lamb waves-based icing real-time detection in the presence of spray ***,a combination of the Hampel median filter and the moving average filter is developed to analyze ToF/ToD *** simulation results reveal a positive correlation between geometric dimensions(length,width,thickness)of the ice layer and ToF/ToD of B1 mode waves,indicating their potential as indicators for quantifying ice *** results of real-time icing detection indicate that ToF/ToD will reach greater peak values with the growth of the arbitrary-shaped ice layer until saturation to effectively predict the simulation *** study lays a foundation for the practical application of quantitative icing detection via ultrasonic guided waves.

关键词： Ice Ice accumulation Ultrasonic sensor Ultrasonic guided wave Lamb wave Wavelet transform

Active disturbance rejection distributed secondary control for DC microgrids

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High Voltage 2024年第1期9卷 241-251页

作者： Jianlin Li Honghao You Shuo Liu Xingchen Li Ziyang Ding Fei Zou National User-Side Energy Storage Innovation research and development center North China University of TechnologyBeijingChina

A novel control scheme is presented to eliminate the negative effects of communication disturbances,which introduces active disturbance rejection control(ADRC)in the control strategy design to achieve the objectives of the restoration of the bus voltage and the sharing of the power even in the presence of disturbances and delays in ***,its dynamic disturbance decoupling feature is used to realise the decoupling between power and voltage,so that the proposed controller only exchanges power information with its neighbours,reducing the communication burden and simplifying control *** control performance of the strategy is verified by employing steady-state *** impact of controller parameters is studied by establishing a small signal ***,both simulation cases and experimental tests prove the feasibility of this scheme.

关键词： Active disturbance establishing

Wireless semantic communication based on semantic matching multiple access and intent bias multiplexing

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The Journal of China Universities of Posts and Telecommunications 2024年第1期31卷 26-36页

作者： Ren Chao He Zongrui Sun Chen Li Haojin Zhang Haijun University of Science and Technology Beijing Beijing 100083China research and development center Sony(China)LimitedBeijing 100027China

This paper proposes a multi-access and multi-user semantic communication scheme based on semantic matching and intent deviation to address the increasing demand for wireless users and *** scheme enables flexible management of long frames,allowing each unit of bandwidth to support a higher number of *** leveraging semantic classification,different users can independently access the network through the transmission of long concatenated sequences without modifying the existing wireless communication *** overcome the potential disadvantage of incomplete semantic database matching leading to semantic intent misunderstanding,the scheme proposes using intent deviation as an *** allows different receivers to interpret the same semantic information differently,enabling multiplexing where one piece of information can serve multiple users with distinct *** results show that at a bit error rate(BER)of 0.1,it is possible to reduce the transmission by approximately 20 semantic basic units.

关键词： semantic communication multiple access multiplexing multimodal communication

Influence of syngas components and ash particles on the radiative heat transfer in a radiant syngas cooler

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Chinese Journal of Chemical Engineering 2024年第4期68卷 203-215页

作者： Chen Han Youmin Situ Huaxing Zhu Jianliang Xu Zhenghua Dai Guangsuo Yu Haifeng Liu National Energy Coal Gasification Technology research and development center East China University of Science and TechnologyShanghai 200237China Shanghai Engineering research center of Coal Gasification East China University of Science and TechnologyShanghai 200237China

Radiant syngas cooler(RSC)is widely used as a waste heat recovery equipment in industrial *** this work,an RSC with radiation screens is established and the impact of gaseous radiative property models,gas components,and ash particles on heat transfer is investigated by the numerical simulation *** the syngas components and the pressure environment of the RSC,a modified weighted-sum-of-gray-gases model was *** modified model shows high accuracy in *** computational fluid dynamics simulation,the calculated steam production is only 0.63%in error with the industrial *** with Smith's model,the temperature decay along the axial direction calculated by the modified model is *** components are of great significance to heat recovery capacity,especially when the absorbing gas fraction is less than 10%.After considering the influence of particles,the outlet temperature and the proportion of radiative heat transfer are less affected,but the difference in steam output reaches 2.7 t·h^(-1).The particle deposition on the wall greatly reduces the heat recovery performance of an RSC.

关键词： Radiant syngas cooler Weighted-sum-of-gray-gases model Numerical simulation Particle radiation

Diagnosing ratio of electron density to collision frequency of plasma surrounding scaled model in a shock tube using low-frequency alternating magnetic field phase shift

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Chinese Physics B 2024年第5期33卷 519-530页

作者：吴明兴谢楷刘艳徐晗张宝田得阳 School of Aerospace Science and Technology Xidian UniversityXi'an 710071China Hypervelocity Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang 621000China

A non-contact low-frequency(LF)method of diagnosing the plasma surrounding a scaled model in a shock tube is *** method utilizes the phase shift occurring after the transmission of an LF alternating magnetic field through the plasma to directly measure the ratio of the plasma loop average electron density to collision *** equivalent circuit model is used to analyze the relationship of the phase shift of the magnetic field component of LF electromagnetic waves with the plasma electron density and collision *** applicable range of the LF method on a given plasma scale is *** upper diagnostic limit for the ratio of the electron density(unit:m^(-3))to collision frequency(unit:Hz)exceeds 1×10^(11),enabling an electron density to exceed 1×10^(20)m^(-3)and a collision frequency to be less than 1 *** this work,the feasibility of using the LF phase shift to implement the plasma diagnosis is also *** experiments on shock tube equipment are conducted by using both the electrostatic probe method and LF *** comparing the diagnostic results of the two methods,the inversion results are relatively consistent with each other,thereby preliminarily verifying the feasibility of the LF *** ratio of the electron density to the collision frequency has a relatively uniform distribution during the plasma *** LF diagnostic path is a loop around the model,which is suitable for diagnosing the plasma that surrounds the ***,the causes of diagnostic discrepancy between the two methods are *** proposed method provides a new avenue for diagnosing high-density enveloping plasma.

关键词： low-frequency alternating magnetic field phase shift shock-tube plasma diagnosis electron density collision frequency

Aerodynamic/stealth design of S-duct inlet based on discrete adjoint method

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 725-746页

作者： Jun DENG Ke ZHAO Lin ZHOU Wei ZHANG Bowen SHU Jiangtao HUANG Zhenghong GAO School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Aerospace Technology Institute of China Aerodynamic Research and Development CenterMianyang 621000Sichuan ProvinceChina

It is a major challenge for the airframe-inlet design of modern combat aircrafts,as the flow and electromagnetic wave propagation in the inlet of stealth aircraft are very *** this study,an aerodynamic/stealth optimization design method for an S-duct inlet is *** upwind scheme is introduced to the aerodynamic adjoint equation to resolve the shock wave and flow *** multilevel fast multipole algorithm(MLFMA)is utilized for the stealth adjoint equation.A dorsal S-duct inlet of flying wing layout is optimized to improve the aerodynamic and stealth *** the aerodynamic and stealth characteristics of the inlet are effectively ***,the optimization results are analyzed,and it shows that the main contradiction between aerodynamic characteristics and stealth characteristics is the centerline and crosssectional *** S-duct is smoothed,and the cross-sectional area is increased to improve the aerodynamic characteristics,while it is completely opposite for the stealth *** radar cross section(RCS)is reduced by phase cancelation for low frequency *** method is suitable for the aerodynamic/stealth design of the aircraft airframe-inlet system.

关键词： S-duct inlet aerodynamic/stealth optimization design discrete adjoint upwind scheme multilevel fast multipole algorithm(MLFMA)

The Burden of Hypertension-Related Chronic Kidney Disease—China,2010–2019

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China CDC weekly 2024年第14期6卷 282-288页

作者： Youyuan Bu Yueru Liu Maigeng Zhou Peng Yin Kejun Liu Yamin Bai Xuancheng Lu Chinese center for Disease Control and Prevention BeijingChina National center for Chronic and Non-Communicable Disease Control and Prevention Chinese Center For Disease Control and PreventionBeijingChina China National Health development research center BeijingChina

What is already known about this topic?The global burden of chronic kidney disease(CKD)is on the *** is added by this report?In 2019,5.58 million individuals in China were affected by CKD related to hypertension,leading to 70,260 fatalities and 1.69 million disability-adjusted life years(DALYs).The most affected groups were men,older individuals,and residents of western *** the period from 2010–2019,the age-standardized prevalence rate(ASPR)remained constant,and the agestandardized mortality rate(ASMR)and agestandardized DALY rate(ASDR)showed a decreasing ***,there was an increase in the number of cases,deaths,and DALYs associated with this *** are the implications for public health practice?Hypertension significantly contributes to the burden of CKD;therefore,raising awareness and implementing early screening measures are essential.

关键词： Kidney mortality burden

An anti-icing scaling method for wind tunnel tests of aircraft thermal ice protection system

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Chinese Journal of Aeronautics 2024年第6期37卷 1-6页

作者： Yu LIU Qiang WANG Xian YI Ningli CHEN Jinghao REN Weihao LI Key Laboratory of Icing and Anti/de-icing China Aerodynamics Research and Development CenterMianyang 621000China State Key Laboratory of Aerodynamics Mianyang 621000China

The efficiency of the aircraft Ice Protection Systems(IPSs)needs to be verified through icing wind tunnel ***,the scaling method for testing the IPSs has not been systematically established yet,and further research is *** the present study,a scaling method specifically designed for thermal IPSs was derived from the governing equation of thin water *** scaling parameters were adopted to address the heat and mass transfer involved in the thermal anti-icing *** method validation,icing wind tunnel tests were conducted using a jet engine nacelle model equipped with a bleed air *** non-dimensional surface temperature and runback ice closely matched for both the reference and scaled *** validation confirms that the scaling method is capable of achieving the similarity of surface temperature and the runback ice *** anti-icing scaling method can serve as an important supplement to the existing icing similarity theory.

关键词： Scaling method Ice protection system Water film Anti-icing test Icing wind tunnel

Neuropeptide Y receptor Y8b(npy8br)regulates feeding and digestion in Japanese medaka(Oryzias latipes)larvae:evidence from gene knockout

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第7期25卷 605-616页

作者： Xiaodan JIA Ke LU Xufang LIANG College of Fisheries Chinese Perch Research CenterHuazhong Agricultural UniversityWuhan 430070China Engineering research center of Green development for Conventional Aquatic Biological Industry in the Yangtze River Economic Belt Ministry of EducationWuhan 430070China

Neuropeptide Y receptor Y8(NPY8R)is a fish-specific receptor with two subtypes,NPY8AR and *** in expression levels during physiological processes or in vivo regulation after ventricular injection suggest that NPY8BR plays an important role in feeding regulation;this has been found in only a few fish,at *** order to better understand the physiological function of npy8br,especially in digestion,we used clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)technology to generate npy8br-/-japanese medaka(Oryzias latipes).We found that the deletion of npy8br in medaka larvae affected their feeding and digestion ability,ultimately affecting their ***,npy8br deficiency in medaka larvae resulted in decreased feed intake and decreased expression levels of orexigenic genes(npy and agrp).npy8br-/-medaka larvae fed for 10 d(10th day of feeding)still had incompletely digested brine shrimp(Artemia nauplii)in the digestive tract 8 h after feeding,the messenger RNA(mRNA)expression levels of digestion-related genes(amy,lpl,ctra,and ctrb)were significantly decreased,and the activity of amylase,trypsin,and lipase also significantly *** deletion of npy8br in medaka larvae inhibited the growth and significantly decreased the expression of growth-related genes(gh and igf1).Hematoxylin and eosin(H&E)sections of intestinal tissue showed that npy8br-/-medaka larvae had damaged intestine,thinned intestinal wall,and shortened intestinal *** far,this is the first npy8br gene knockout model established in fish and the first demonstration that npy8br plays an important role in digestion.

关键词： Neuropeptide Y receptor Y8b(npy8br) Japanese medaka(Oryzias latipes) Knockout Feeding Digestion