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Joint Design of ISAC Waveform Under PAPR Constraints

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China Communications 2024年第7期21卷 186-211页

作者： Chen Yating Wen Cai huang yan Liang Le Li Jie Zhang Hui hong Wei State Key Lab of Millimeter Waves Southeast UniversityNanjing 211100China School of Information Science and Technology Northwest UniversityXi’an 710127China National Mobile Communications Research Laboratory Nanjing 211100China College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211100China

In this paper,we formulate the precoding problem of integrated sensing and communication(ISAC)waveform as a non-convex quadratically constrained quadratic programming(QCQP),in which the weighted sum of communication multi-user interference(MUI)and the gap between dual-use waveform and ideal radar waveform is minimized with peak-toaverage power ratio(PAPR)*** propose an efficient algorithm based on alternating direction method of multipliers(ADMM),which is able to decouple multiple variables and provide a closed-form solution for each *** addition,to improve the sensing performance in both spatial and temporal domains,we propose a new criteria to design the ideal radar waveform,in which the beam pattern is made similar to the ideal one and the integrated sidelobe level of the ambiguity function in each target direction is minimized in the region of *** limited memory Broyden-Fletcher-Goldfarb-Shanno(LBFGS)algorithm is applied to the design of the ideal radar waveform which works as a reference in the design of the dual-function *** results indicate that the designed dual-function waveform is capable of offering good communication quality of service(QoS)and sensing performance.

关键词： ambiguity function integrated sensing and communication MIMO OFDM PAPR waveform design

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轴对称喷管内外流场与结构温度场耦合计算

推进技术 2008年第2期29卷 194-198,229页

作者：黄宏艳王强北京航空航天大学能源与动力工程学院北京100083

利用有限体积的对流项二次迎风插值格式和重整化群(RNG)k-ε湍流模型,二层增强型壁面函数,同时利用球形谐波法考虑热辐射的影响,以灰气体加权模型(WSGGM)确定气体介质的辐射性质,求解N-S方程、热传导方程、考虑吸收-发射性气体介质的辐... 详细信息

利用有限体积的对流项二次迎风插值格式和重整化群(RNG)k-ε湍流模型,二层增强型壁面函数,同时利用球形谐波法考虑热辐射的影响,以灰气体加权模型(WSGGM)确定气体介质的辐射性质,求解N-S方程、热传导方程、考虑吸收-发射性气体介质的辐射传输方程。采用流固耦合的流动与换热模型,流场与结构温度场互为边界条件交换数据,实现了流场解算与温度场解算的耦合数值分析。采用此计算模型对静止的轴对称收-扩喷管进行了数值模拟,计算得到的喷管壁温与试验数据吻合良好。在此基础上,进一步开展了巡航状态下轴对称收-扩喷管内外流场与结构温度场的耦合数值研究。

关键词：流动特性温度场流固耦合耦合传热数值仿真

Tuning the membrane rejection behavior by surface wettability engineering for an effective water-in-oil emulsion separation

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Chinese Chemical Letters 2024年第6期35卷 480-485页

作者： yan Zou Yin-Shuang Hu Deng-Hui Tian hong Wu Xiaoshu Lv Guangming Jiang Yu-Xi huang Engineering Research Center for Waste Oil Recovery Technology and Equipment Ministry of EducationChongqing Technology and Business UniversityChongqing 400067China School of Environmental Science and Engineering Sun Yat-sen UniversityGuangzhou 510275China Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology(Sun Yat-sen University) Guangzhou 510275China

Membrane-based separation is a promising technology to eliminate water impurities from the oil ***,it remains a great challenge to separate water from highly emulsified viscous oil owing to the high stability of the water droplets in *** we report a surface wettability engineering on an alumina ceramic membrane to achieve an efficient separation of a water-in-oil(W/O)*** with different carbon chain lengths and fluorinated status were introduced to endow the alumina membrane with different surface *** all the modified membranes exhibited excellent separation of the W/O without Span 80(surfactant),the one with amphiphobic wettability and lowest surface energy failed to separate the Span 80 stabilized W/*** presence of Span 80 reduced the interfacial tension of water droplets,making them easier to deform and penetrate the modified membrane with the lowest surface *** reveals that engineering proper surface wettability is the key to separating the oil and water ***,the modified membranes maintained decent separation performance and stability under long-term run separation of the emulsified W/O.

关键词： Water-in-oil emulsion Ceramic membrane Membrane separation Surface wettability

过膨胀状态下轴对称收-扩喷管内外流场计算及分析

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航空动力学报 2007年第7期22卷 1069-1073页

作者：黄宏艳王强北京航空航天大学能源与动力工程学院北京100083

轴对称收-扩喷管在过膨胀状态下工作时,喷管内部将产生强烈的激波以及附面层分离,流态非常复杂.计算实践表明,应用广泛采用的重整化群(RNG)k-ε湍流模型,并结合标准壁面函数对其进行数值模拟时,误差较大.针对标准壁面函数的不足,采用增... 详细信息

轴对称收-扩喷管在过膨胀状态下工作时,喷管内部将产生强烈的激波以及附面层分离,流态非常复杂.计算实践表明,应用广泛采用的重整化群(RNG)k-ε湍流模型,并结合标准壁面函数对其进行数值模拟时,误差较大.针对标准壁面函数的不足,采用增强型壁面函数处理固体壁面附近的流动,对轴对称收-扩喷管的内外流场进行了数值模拟,并与试验数据进行了分析比较.结果表明:增强型壁面函数更加适合处理此类存在强逆压梯度导致附面层分离的问题.

关键词：航空航天推进系统壁面函数流动特性数值模拟过膨胀附面层分离

Coupling analysis method of grouting construction with deformation response of adjacent existing tunnel

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Underground Space 2024年第2期15卷 312-330页

作者： Ping-wei Jiang Zhi-hong Zhang hong Zheng Jin-kun huang Key Laboratory of Urban Security and Disaster Engineering of China Ministry of Education Beijing University of TechnologyBeijing 100124China China MCC17 Group Co.LTD MaanshanAnhui 243000China School of Naval Architecture Ocean and Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China

In the new tunnel under close distance through the existing tunnel risk source,the grouting scheme developed to compensate for stratum losses is still based on empirical methods,relying on the overburden thickness of existing *** can potentially lead to an excessively high or low probability of uplift of existing *** a coupled deformation analysis method between the grouting construction and adjacent existing tunnels is of great theoretical significance for developing grouting *** order to reasonably limit the design parameters of grouting construction,based on the theory of fluid–solid coupling elastic pore-column expansion and the theory of random media,the calculation method of stratum displacement which simultaneously considers the coexistence of grout compaction expansion and permeability diffusion mode is derived,and the accuracy of the calculation method is verified by engineering *** accuracy of this calculation method was verified through engineering *** with the deformation coordination condition,the existing tunnel is regarded as an elastic Euler-Bernoulli continuous beam,and the finite element coupling balance equation of the interaction between the existing tunnel and the surrounding soil is *** on this,a coupling calculation model of the grouting construction and the deformation response of the adjacent existing tunnel is *** with three times of grouting construction examples in the shield tunneling project of Beijing Metro Line 12 under the existing airport line,the reliability of the coupling calculation model to determine the grouting construction parameters is *** calculation parameters in the coupling calculation model have clear physical meanings,which can provide a theoretical basis for the grouting design of similar risk source projects.

关键词： Grouting Close-range underpass Tunnel Random medium theory Euler-Bernoulli continuous beam

Review on synergistic damage effect of irradiation and corrosion on reactor structural alloys

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Nuclear Science and Techniques 2024年第3期35卷 109-141页

作者： Hui Liu Guan-hong Lei He-Fei huang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

The synergistic damage effect of irradiation and corrosion of reactor structural materials has been a prominent research *** paper provides a comprehensive review of the synergistic effects on the third-and fourth-generation fission nuclear energy structural materials used in pressurized water reactors and molten salt *** competitive mechanisms of multiple influencing factors,such as the irradiation dose,corrosion type,and environmental temperature,are summarized in this *** approaches are proposed to alleviate the synergistic damage caused by irradiation and corrosion,thereby promoting in-depth research in the future and solving this key challenge for the structural materials used in reactors.

关键词： Irradiation and corrosion Synergistic effect Austenitic stainless steels Nickel-based alloys Reactors

Synergistic Tuning of Nickel Cobalt Selenide@Nickel Telluride Core-Shell Heteroarchitectures for Boosting Overall Urea Electrooxidation and Electrochemical Supercapattery

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Energy & Environmental Materials 2024年第1期7卷 301-312页

作者： Diab Khalafallah Weibo huang Mingjia Zhi Zhanglian hong State Key Laboratory of Silicon Material School of Materials Science and EngineeringZhejiang University38 Zheda RoadHangzhou 310027China Mechanical Design and Materials Department Faculty of Energy EngineeringAswan UniversityP.O.Box 81521AswanEgypt

Herein,we demonstrate the synthesis of bifunctional nickel cobalt selenide@nickel telluride(Ni_(x)Co_(12-x)Se@NiTe)core-shell heterostructures via an electrodeposition approach for overall urea electrolysis and *** 3D vertically orientated NiTe dendritic frameworks induce the homogeneous nucleation of 2D Ni_(x)Co_(12-x)Se nanosheet arrays along similar crystal directions and bring a strong interfacial binding between the integrated active *** particular,the optimized Ni_(6)Co_(6)Se@NiTe with an interface coupling effect works in concert to tune the intrinsic *** only needs a low overpotential of 1.33 V to yield a current density of 10 mA cm^(-2)for alkaline urea ***,the full urea catalysis driven only by Ni_(6)Co_(6)Se@NiTe achieves 10 mA cm^(-2)at a potential of 1.38 V and can approach a constant level of the current response for 40 ***,the integrated Ni_(6)Co_(6)Se@NiTe electrode delivers an enhanced specific capacity(223 mA h g^(-1)at 1 A g^(-1))with a high cycling ***,a hybrid asymmetric supercapacitor(HASC)device based on Ni_(6)Co_(6)Se@NiTe exhibits a favorable rate capability and reaches a high energy density of 67.7 Wh kg^(-1)and a power density of 724.8 W kg^(-1)with an exceptional capacity retention of 92.4%after sequential 12000 cycles at 5 A g^(-1).

关键词： bifunctional Ni_(x)Co_(12-x)Se@NiTe core-shell electrodeposition heterointerfaces supercapacitors UOR

Energy absorption behaviors of a novel buffer lander-leg with Yoshimura core

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Chinese Journal of Aeronautics 2024年第4期37卷 333-342页

作者： yan XU He huang Chao ZHANG Rongji FU School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310027China School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical UniversityXi’an 710072China

In the current soft-landing system,the lander-leg and the buffer are two independent parts which may cause weight *** traditional mechanical buffers also have their own shortcomings such as small buffer stroke and being non-reusable.A Novel Buffer Lander-leg with Yoshimura core (NBLY) is proposed in this paper,inspired by the Buckling Restrained Brace(BRB).The design details of NBLY and parameter definitions of the core are *** finite element analysis modes have been employed to analyze the nonlinear mechanical behaviors of NBLY subjected to the cyclic *** with four different core styles of hexagon,octagon,dodecagon and hexadecagon are analyzed and *** restraining ratio and cumulative dissipation energy ratio have been obtained to evaluate the energy absorption *** results show that the origami pattern has significant influences on the deformation ductility,plastic energy absorbing and axial load transferring to the *** NBLY with octagon core has outstanding properties,especially the hysteretic energy dissipation and enhancement of compression *** interaction mechanism between the core and encasing member constrains the deformation extensions and contributes to the frictional energy dissipation of the *** paper provides a new conceptual design of buffer lander-leg for soft-landing *** can realize the reuse function as a buffer lander-leg with better loading-bearing and energy absorption behaviors.

关键词： Lander-leg structure Origami Energy absorption Cyclic loading Finite element analysis

Prevalence and Influencing Factor Analysis of Typhoid/Paratyphoid Fever—China,2011-2020

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China CDC weekly 2024年第21期6卷 493-498页

作者： Shumei huang Meiying yan Biao Kan School of Public Health Shandong UniversityJinan CityShandong ProvinceChina National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases National Institute for Communicable Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina

Introduction:Over the last 12 years,there has been a consistent decline in the cases of typhoid/paratyphoid fever in *** the epidemiological patterns of these diseases in various provincial-level administrative divisions(PLADs)and examining potential influencing factors can provide crucial information for implementing successful control ***:In this study,we analyzed the cases and incidence rates of typhoid/paratyphoid fever reported in various PLADs of China from 2011 to 2022,along with exploring potential influencing *** initially studied spatial shifts in the incidence rates through centroid shift *** variations in typhoid/paratyphoid fever onset were examined using *** autocorrelation analysis was utilized to understand the spatial correlations among different *** assess potential factors,we utilized a generalized estimating equations model that integrated spatial lag effects and sequence comparison ***:The study identified significant geographical clustering of typhoid/paratyphoid fever cases in southwestern China.A decrease in incidence rates in the west resulted in a movement of the disease center towards the *** incidence occurred during warmer seasons,highlighting the seasonal pattern of the *** such as meteorological conditions and socioeconomic status were probable influencers of typhoid/paratyphoid ***:The geographical and temporal spread of typhoid/paratyphoid fever can be impacted by meteorological and socioeconomic *** economic conditions,particularly in regions with high disease prevalence,could aid in the prevention and management of these fevers.

关键词： prevention utilized meteorological