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On-line trajectory generation of midcourse cooperative guidance for multiple interceptors

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Journal of systems Engineering and Electronics 2022年第1期33卷 197-209页

作者： CHEN Wenyu sHAO lei lei Humin Air and Missile Defense College Air Force Engineering UniversityXi’an 710051China

The cooperative interception trajectories generation of multiple interceptors to hypersonic targets is ***,to solve the problem of on-line trajectory generation of the single interceptor,a generation method based on neighborhood optimal control is ***,when intercepting the strong maneuvering targets,the single interceptor is insufficient in maneuverability,therefore,an on-line multiple trajectories generation algorithm is proposed,which uses the multiple interceptors intercept area(IIA)to cover the target's predicted intercept area(PIA)*** optimizing the interceptors'zero control terminal location,the trajectories are generated on-line by using the neighborhood optimal control method,these trajectories could make the IIA maximally cover the *** simulation results show that the proposed method can greatly improve the interception probability,which provides a reference for the collaborative interception of multiple interceptors.

关键词： cooperative interception trajectories generation near space

Effect of deep cryogenic treatment on the microstructural,mechanical and ballistic properties of AA7075-T6 aluminum alloy

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Defence Technology（防务技术） 2023年第12期30卷 101-110页

作者： s.Dharani kumar u.Magarajan s.urabh s Kumar Rodríguez-Millan M Centre for Machining and Material Testing KPR Institute of Engineering and TechnologyCoimbatoreIndia Department of Mechanical Engineering Sri Venkateswara College of EngineeringChennaiIndia scientific Officer Ballistic Research Centre&Testing RangeNational Forensic Sciences UniversityGandhi NagarIndia Department of Mechanical Engineering University Carlos Ⅲ of MadridLeganesMadridSpain

The s.udy focused on investigating the effect of Deep Cryogenic Treatment(DCT)on the mechanical and ballistic properties of AA7075-T6 aluminum *** microstructure,microhardness,tensile strength,and impact strength of the Base Material(BM)and DCT-treated 7075 samples were analyzed through metallographic analysis and mechanical *** microstructure of the DCT-treated 7075 samples revealed fine grains and a distribution of secondary phase *** tensile strength,impact strength,and microhardness of DCT-treated samples increased by 7.41%,4%,and 9.68%,respectively,compared to the BM *** fractography analysis of the tensile samples showed cleavage facets,microvoids,and dimples in both the *** ballistic behavior of the BM and DCT target plates were s.udied by impacting hard steel core projectiles at a velocity of 750±10 m/*** target plates failed due to petaling and ductile hole enlargement,and the depth of penetration(DOP)of the DCT target was less than that of the BM target,indicating a higher ballistic *** post-ballistic microstructure examination of the target plates showed the formation of an Adiabatic shear Band(AsB)without any *** was concluded that the DCT treatment improved the mechanical and ballistic properties of the aluminum alloy due to grain refinement and high dislocation density.

关键词： Deep cryogenic treatment AA7075-T6 Mechanical properties Ballistic Adiabatic shear band

Trace-Rare-Gas Optical Emission spectroscopy of Nitrogen Plasma Generated at a Frequency of 13.56 MHz

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Plasma science and Technology 2011年第2期13卷 208-212页

作者： N.u.REHMAN F.u.KHAN s.NAsEER G.MuRTAZA s.s.HussAIN I.AHMAD M.ZAKAuLLAH Department of Physics COMSATS Institute of Information Technology Department of Physics Gomal University Department of Physics Peshawar University Department of Physics Quaid-i-Azam University

Optical emission spectroscopic measurement of trace rare gas is carried out to determine the density of nitrogen （N） atom, in a nitrogen plasma, as a function of filling pres.ure and RF power applied. 2% of argon, used as an actinometer, is mixed with nitrogen. In order to normalize the changes in the excitation cross section and electron energy distribution function at different operational conditions, the Ar-I emission line at 419.83 nm is.used, which is of nearly the same excitation efficiency coefficient as that of the nitrogen emission line at 493.51 nm. It is observed that the emission intensity of the selected argon and atomic nitrogen lines increases with both pres.ure and RF power, as does the nitrogen atomic density.

关键词： optical actinometry N atomic density EEDF RF plasma

Incorporation of a nanotechnology-based additive in cementitious products for clay stabilisation

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Journal of Rock Mechanics and Geotechnical Engineering 2020年第5期12卷 1056-1069页

作者： E.u.Eyo s.Ng’ambi s.J.Abbey school of Energy Construction and EnvironmentFaculty of EngineeringEnvironment and ComputingCoventry UniversityCoventryUK Faculty of Environment and Technology Department of Geography and Environmental ManagementCivil Engineering ClusterUniversity of the West of EnglandBristolUK

The mechanical performances and water retention characteristics of clays,stabilised by partial substitution of cement with by-products and inclusion of a nanotechnology-based additive called RoadCem(RC),are s.udied in this *** unconfined compression tests and one-dimensional oedometer swelling were performed after 7 d of curing to understand the influence of addition of 1%of RC material in the stabilised soils with the cement partially replaced by 49%,59%and 69%of ground granulated blast furnace slag(GBBs)or pulverised fuel ash(PFA).The mois.ure retention capacity of the stabilised clays was also explored using the soil-water retention curve(sWRC)from the measured *** confirmed an obvious effect of the use of RC with the obtained strength and swell properties of the stabilised clays suitable for road application at 50%replacement of *** outcome is associated with the in-depth and penetrating hydration of the cementitious materials by the RC and water which results in the production of needle-like matrix with interlocking filaments e a phenomenon referred to as the‘wrapping’*** the other hand,the sWRC used to describe the water holding capacity and corresponding swell mechanism of clays stabilised by a proportion of RC showed a satisfactory *** mois.ure retention of the RC-modified clays was initially higher but reduced subsequently as the saturation level increased with decreasing *** phenomenon confirmed that clays stabilised by including the RC are water-proof in nature,thus ensuring reduced porosity and suction even at reduced water ***,the stabilised clays with the combination of cement,GGBs and RC showed a better performance compared to those with the PFA included.

关键词： Cement Ground granulated blast furnace slag(GBBs) Fly ash RoadCem(RC) swell stabilisation unconfined compressive strength soil-water retention curve(sWRC)

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引线键合的动力相图和等效受载模型

电子学报 2010年第11期38卷 2697-2703页

作者：韩雷吕雷中南大学机电工程学院湖南长沙410083

使用常规、微观电镜、动力相图和统计时频分析等方法,进行了引线键合机理的实验研究.通过对换能系统和劈刀振速的高频分量、键合压力的测试,以及键合界面微观结构的观察,建立了键合区域宏观受载等效模型,和对键合机理的框架认识.可作为... 详细信息

使用常规、微观电镜、动力相图和统计时频分析等方法,进行了引线键合机理的实验研究.通过对换能系统和劈刀振速的高频分量、键合压力的测试,以及键合界面微观结构的观察,建立了键合区域宏观受载等效模型,和对键合机理的框架认识.可作为键合过程优化的指导,和键合动力学建模的依据.

关键词：引线键合非线性动力学多普勒测速小波时频分解动力相图

A carbuncle cure for the Harten-Lax-van Leer contact(HLLC)scheme using a novel velocity-based sensor

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Applied Mathematics and Mechanics(English Edition) 2021年第9期42卷 1259-1278页

作者： u.s.VEVEK B.ZANG T.H.NEW Department of Mechanical Materials and Aerospace EngineeringUniversity of LiverpoolLiverpool L693BXUnited Kingdom Department of Aerospace Engineering University of BristolBristol BS81TRUnited Kindgdom school of Mechanical and Aerospace Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore

A hybrid numerical flux scheme is proposed by adapting the carbunclefree modified Harten-Lax-van Leer contact(HLLCM) scheme to smoothly revert to the Harten-Lax-van Leer contact(HLLC) scheme in regions of shear. This hybrid scheme, referred to as the HLLCT scheme, employs a novel, velocity-based shear sensor. In contrast to the non-local pres.ure-based shock sensors often used in carbuncle cures, the proposed shear sensor can be computed in a localized manner meaning that the HLLCT scheme can be easily introduced into existing codes without having to implement additional data structures. Through numerical experiments, it is shown that the HLLCT scheme is able to resolve shear layers accurately without succumbing to the shock instability.

关键词： carbuncle shock instability Euler equation numerical flux Harten-Laxvan Leer contact(HLLC)scheme

Proteins moonlighting in tumor metabolism and epigenetics

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Frontiers of Medicine 2021年第3期15卷 383-403页

作者： lei Lv Qunying lei MOE Key Laboratory of Metabolism and Molecular Medicine Department of Biochemistry and Molecular BiologySchool of Basic Medical SciencesFudan UniversityShanghai 200032China Fudan university shanghai Cancer Center&Institutes of Biomedical sciences Cancer InstitutesKey Laboratory of Breast Cancer in ShanghaiThe Shanghai Key Laboratory of Medical EpigeneticsShanghai Medical CollegeFudan UniversityShanghai 200032China Department of Oncology Shanghai Medical CollegeFudan UniversityShanghai 200032China state Key Laboratory of Medical Neurobiology Fudan UniversityShanghai 200032China

Cancer development is a complicated process controlled by the interplay of multiple signaling pathways and restrained by oxygen and nutrient accessibility in the tumor *** plasticity in using diverse nutrients to adapt to metabolic stress is one of the hallmarks of cancer *** respond to nutrient stress and to meet the requirements for rapid cell proliferation,cancer cells reprogram metabolic pathways to take up more glucose and coordinate the production of energy and intermediates for *** actions involve gene expression and activity regulation by the moonlighting function of oncoproteins and metabolic *** signal−moonlighting protein−metabolism axis facilitates the adaptation of tumor cells.under varying environment conditions and can be therapeutically targeted for cancer treatment.

关键词： moonlighting function tumor metabolism epigenetics

Detection of Perfect stealthy Attacks on Cyber-Physical systems subject to Measurement Quantizations: A Watermark-Based strategy

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IEEE/CAA Journal of Automatica sinica 2025年第1期 114-125页

作者： Yu-Ang Wang Zidong Wang lei Zou Bo shen Hongli Dong the College of Information science and Technology Donghua University the Engineering Research Center of Digitalized Textile and Fashion Technology Ministry of Education IEEE the College of Electrical Engineering and Automation Shandong University of Science and Technology the Department of Computer science Brunel University London Uxbridge the sanya Offshore Oil and Gas Research Institute Northeast Petroleum University the Artificial Intelligence Energy Research Institute Northeast Petroleum University Heilongjiang Provincial Key Laboratory of Networking and Intelligent Control Northeast Petroleum University

In this paper, the attack detection problem is investigated for a class of closed-loop systems subjected to unknownbutbounded noises in the presence of stealthy attacks. The measurement outputs from the sensors are quantized before transmission.A specific type of perfect stealthy attack, which meets certain rather stringent conditions, is taken into account. such attacks could be injected by adversaries into both the sensor-toestimator and controller-to-actuator channels, with the aim of dis.upting the normal data flow. For the purpose of defending against these perfect stealthy attacks, a novel scheme based on watermarks is developed. This scheme includes the injection of watermarks(applied to data prior to quantization) and the recovery of data(implemented before the data reaches the estimator).The watermark-based scheme is designed to be both timevarying and hidden from adversaries through incorporating a time-varying and bounded watermark signal. subsequently, a watermark-based attack detection strategy is proposed which thoroughly considers the characteristics of perfect stealthy attacks,thereby ensuring that an alarm is activated upon the occurrence of such attacks. An example is provided to demonstrate the efficacy of the proposed mechanism for detecting attacks.

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非静水压环境对u_(3)O_(8)高压拉曼声子行为的影响

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光谱学与光谱分析 2025年第1期45卷 59-65页

作者：王艺佳吴彬彬刘静仪房雷鸣刘本琼雷力四川大学原子与分子物理研究所四川成都610065 中国工程物理研究院核物理与化学研究所四川绵阳621022

八氧化三铀(u_(3)O_(8))是动力学和热力学最稳定的铀氧化物。研究u_(3)O_(8)的高压相稳定性和高压声子行为对其在核工业、催化剂等领域的应用具有重要参考价值。由于铀原子([Rn]5f^(3)6d^(1)7s^(2))和氧原子([He]2s^(2)2p^(4))核外电子... 详细信息

八氧化三铀(u_(3)O_(8))是动力学和热力学最稳定的铀氧化物。研究u_(3)O_(8)的高压相稳定性和高压声子行为对其在核工业、催化剂等领域的应用具有重要参考价值。由于铀原子([Rn]5f^(3)6d^(1)7s^(2))和氧原子([He]2s^(2)2p^(4))核外电子结构存在显著差异,因此很难通过同步辐射X射线衍射技术探测高压下铀氧化合物中u-O键合的细微变化。然而拉曼光谱对高压下u-O键合变化非常敏感,它能揭示物质在高压下包括键合或者化学计量等方面的重要信息。目前对u_(3)O_(8)高压结构相变的研究通常聚焦于静水压环境,而非静水压环境对u_(3)O_(8)高压相变的影响尚未得到深入研究。该研究基于金刚石对顶砧的高压拉曼散射技术探究了静水压和非静水压环境对正交α-u_(3)O_(8)高压相变与声子行为的影响。研究表明,静水压(8.1 GPa)和非静水压(8.2 GPa)条件下α-u_(3)O_(8)高压相变起始压力很接近。但由于非静水压环境中样品内的微区偏应力较大,因此非静水压环境中u_(3)O_(8)高压相变结束压力(16.4 GPa)比静水压环境中相应压力(18.5 GPa)约低2~3个GPa。同时本文给出了两对比实验中主拉曼模的一阶压力系数与Mode-Grüneisen参数γ。对比分析可知,高压相变前静水压条件下各主模零压下的一阶压力系数绝对值|dω/d P|几乎均大于非静水压条件下的相应值,这表明相变前非静水压环境中各拉曼模对压力响应不明显;一旦高压相变开始,由于较大微区偏应力的存在极大程度增强了铀氧原子外层电子的耦合作用,故相变后非静水压下压力系数绝对值显著增大。零压下B(6)2模的γ值最小,因此对外部扰动有更积极的响应。此外室温加压时A(3)2和A(4)2模(代表沿a轴氧原子的振动)的一阶压力系数通常小于B(4)2和B(6)2模(代表bc面内氧原子的位移),这表明α-u_(3)O_(8)高压相变前a轴比b、c轴更难被压缩。该工作深入探究了静水压和非静水压环境对α-u_(3)O_(8)高压相变的影响,为了解α-u_(3)O_(8)高压相稳定性和晶格动力学行为提供了重要参考。

关键词： u_(3)O_(8) 高压拉曼光谱高压相变非静水压