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Establishment,simulation and verification of firepower safety control model

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Defence Technology（防务技术） 2022年第10期18卷 1922-1934页

作者： Ling-jun Hao Yu-jie xiao Bing fu xiao-dong Gu Yi Chen Chong-xiang Yang Hai-wen Sun rong Luo Yi He Naval University of Engineering WuhanHubei430033China Naval Research Academy Beijing100161China Nanjing University of Science and Technology NanjingJiangsu210094China

On a narrow warship platform,the coordinated use of shipborne weapon systems may cause firepower conflicts,which seriously endangers the ship ***,with directed-energy weapons mounted on ships,firepower conflicts between weapons become a“high probability event”.Aiming at the problem of firepower safety control,based on the research about the collision probability model of air crafts and space targets and according to the cone of fire model of conventional weapons and directed-energy weapons,this paper solved the firepower conflict probabilities between conventional weapons as well as between conventional weapons and directed-energy weapons respectively using the methods of probability theory,and established the firepower safety control *** the calculation of firepower conflict probability was carried out using the dimensionality reduction method based on the equivalent conversion of polar coordinates and the power series method based on Laplace *** simulation results revealed that the proposed model and calculation methods are effective and reliable,which can provide theoretical basis and technical support for resolution of firepower conflicts between weapons.

关键词： Firepower conflict Directed-energy weapons Firepower safety control Polar coordinates Laplace transform

Catalyst-free hydrochlorination protocol for terminal arylalkynes with hydrogen chloride

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Chinese Chemical Letters 2016年第11期27卷 1683-1685页

作者： Cai-Xia Xu Cun-Hua Ma fu-rong xiao Hong-Wei Chen Bin Dai School of Chemistry and Chemical Engineering Shihezi University/Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan

We present a simple and straightforward protocol for hydrochlorination of terminal arylalkynes to vinyl chlorides using hydrogen chloride under mild reaction conditions. This protocol does not involve any metal catalysts or additives. It is simple, inexpensive, and easy to prepare, and exhibits good reaction activity. The hydrochlorination proceeds smoothly to yield unique regioselective products via the Markovnikov addition rule.

关键词： Hydrochlorination Arylalkynes Vinyl chlorides Catalyst-free Markovnikov addition

A user requirements-oriented privacy policy self-adaption scheme in cloud computing

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Frontiers of Computer Science 2023年第2期17卷 33-44页

作者： Changbo KE fu xiao Zhiqiu HUANG Fangxiong xiao School of Computer Science Nanjing University of Posts and TelecommunicationsNanjing 210003China College of computer science and technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China School of Software Engineering Jinling Institute of TechnologyNanjing 210000China

In an ever-changing environment,Software as a Service(SaaS)can rarely protect users'*** able to manage and control the privacy is therefore an important goal for *** the participant of composite service is substituted,it is unclear whether the composite service satisfy user privacy requirement or *** this paper,we propose a privacy policies automatic update method to enhance user privacy when a service participant change in the composite ***,we model the privacy policies and service variation ***,according to the service variation rules,the privacy policies are automatically generated through the negotiation between user and service ***,we prove the feasibility and applicability of our method with the *** the service quantity is 50,ratio that the services variations are successfully checked by monitor is 81%.Moreover,ratio that the privacy policies are correctly updated is 93.6%.

关键词： cloud computing SaaS service privacy protec-tion privacy policies update

Hydrogen-bonded organic framework core–shell composite for synergistic antimicrobial therapy

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Aggregate 2024年第2期5卷 457-462页

作者： Jian xiao Acharya Ramachandra Mahammed Shaheer Chen Liu Tian-fu Liu rong Cao State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouChina School of Physical Science and Technology ShanghaiTech UniversityShanghaiChina University of Chinese Academy of Sciences BeijingChina

Hydrogen-bonded organic frameworks(HOFs)are crystalline porous materials with permanent voids formed via self-assembly of organic molecules through hydrogen bonding and intermolecular *** combination of HOFs with functional material would broaden their application horizon but were less explored in existing ***,a highly porous and photosensitive HOF was successfully coated onto upconversion nanoparticles(UCNPs)to construct a core-shell structure named UNCPs@*** enhance spectral overlap and maximize energy conversion efficiency,this study utilized the Er and Tm co-doped UCNPs,which can effectively convert infrared light into visible light emission thereby exciting the porphyrin *** investigation reveals that the composite exhibits significant photodynamic and photothermal effects under infrared *** by its noticeable photoactivity,UCNPs@PFC-73-Ni was evaluated as an antibacterial agent against Escherichia ***,significant antibacterial efficacy was observed,highlighting the potential of UCNPs@PFC-73-Ni as an effective antibacterial agent under infrared light irradiation.

关键词： hydrogen-bonded organic frameworks photodynamic therapy photothermal therapy upconversion nanoparticles

Dynamic properties analysis of a stay cable-damper system in consideration of design and construction factors

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Earthquake Engineering and Engineering Vibration 2014年第2期13卷 317-326页

作者： Dan Danhui Chen Yanyang xiao rong Department of Bridge Engineering Tongji University Henan Provincial Communications Planning Survey & Design Institute Co. Ltd

A numerical solution based on the Steffensen stable point iterative method is proposed to resolve the transcendental frequency equation of a stay cable-damper system. The frequency equation, which considers clamped supports and fl exural rigidity of the cable, is intended to investigate the infl uence of the parameters of the cable damper system on its dynamic characteristics. Two factors involved in the design and construction phases, the damping coeffi cient induced by external dampers and the cable tension, are the focus of this study. Their impact on modal frequencies and damping ratios in these two phases of cable-damper systems are investigated by resolving the equation with the proposed solution. It is shown that the damping coeffi cient and cable tension exert more noticeable effects on the modal damping ratios than on the modal frequencies of stay cable-damper systems, and the two factors can serve as design variables in the design phase and as adjustment factors in the construction phase. On the basis of the results, a roadmap for system-level optimal design of stay cable-damper systems that can achieve global optimal vibration suppression for the entire bridge is proposed and discussed.

关键词： cable damper damping coeffi cient cable tension dynamic property optimal design

Magnetic Actuated Shape-memory Helical Microswimmers with Programmable Recovery Behaviors

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Journal of Bionic Engineering 2021年第4期18卷 799-811页

作者： fu Zhao Weibin rong Lefeng Wang Lining Sun State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin150080China

Inspired by bacterial flagella in nature,magnetic helical microswimmer is an ideal model to perform complex task in a low Reynolds number *** Memory Polymers(SMPs)with desirable properties are considered as one of the most preferred options for the development of small-scale ***,fabricating and programming strategies are still ***,we report an approach to fabricate helical microswimmers based on thermoplastic SMP(polylactic acid).Melt-spun polylactic acid fibers containing magnetic particles were enwound to form helical *** shape recovery behaviors were programmed by annealing and *** forms of helical microswimmers(constant-helix-angle conical helix,constant-pitch conical helix,and straight helix)with controlled morphological parameters were *** obtained microswimmers showed 3D locomotion capability under rotating magnetic *** maximum swimming velocity of microswimmers was nearly six body lengths per second,and the near-wall swimming of conical helixes along their sharp end exhibited a smaller ***,we demonstrated programmed shape-switching processes(spring-like contraction and elongation,coiling and uncoiling)and self-repairing of the *** demonstrations of potential applications,tasks of mobile microstent,cargo delivery,and minimally invasive injection were carried *** multifunctional shape-memory microswimmers have immense potential in a variety of applications.

关键词： helical microrobot magnetic actuation Shape Memory Polymer(SMP) polylactic acid magnetic particles

Non-abelian Collective Excitations in Nonlinear Quark-Gluon Plasma Media

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Chinese Physics Letters 2000年第9期17卷 643-645页

作者： ZHENG xiao-Ping HOU De-fu LIU Liang-Gang LI Jia-rong Institute of Particle Physics Huazhong Normal UniversityWuhan 430079 Department of Physics Zhongshan UniversityGuangzhou 510275

We have studied the effect of the third-order density fluctuations in the medium on the collective excitations in quark-gluon *** show that the nonlinear response of a quark-gluon plasma medium leads to non-Abelian collective *** present two kinds of non-Abelian oscillation solutions which respectively correspond to weakly and strongly nonlinear coupling of field components in the color *** also show that the weakly nonlinear solution is similar to the Abelian-like one but has a frequency shift,which is of order g^(2)T,from the eigenfrequency.

关键词： space. weakly collective

The microstructure of a single crystal superalloy after different aging heat treatments

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Rare Metals 2018年第3期37卷 210-216页

作者： xiao-Dai Yue Jia-rong Li xiao-Guang Wang Science and Technology on Advanced High Temperature Structural Materials Laboratory Beijing Institute of Aeronautical Materials

To study the influence of aging heat treatments on the microstructure of single crystal superalloys with high content of refractory elements and optimal the aging heat treatment regimes, a single crystal superalloy containing 22 wt% refractory elements was *** show that for the experimental alloy, even the homogenization-solution heat treatment for 25 h cannot homogenize the alloying elements completely. During primary aging heat treatment, γ＇ phase grows larger and turns to regular cubes. Higher aging temperature induces larger γ＇ cubes. For specimens with primary aging heat treated at 1120 ℃,γ＇ morphology does not change apparently during secondary aging heat treatment. For specimens with primary aging heat treatment at 1150 ℃,γ＇phase in interdendrite grows obviously comparing with that in dendrites. By analyzing the precipitating kinetics of γ＇phase, it is found that owning to the dendrite segregation and different aging heat treatment temperatures, γ＇ phase at different regions grows under the control of different factors at different aging heat treatment stages. The two controlling factors that are driving forces of phase transformation and element diffusion rate induce obviously different growth rates of γ＇ phase. As a result, the γ＇-precipitating behaviors are variable based on different solute concentrations and aging temperatures. For advanced single crystal superalloys that are supposed to be used at relatively high temperatures, the final γ＇ size after aging heat treatment is suggested to be close to the crossing point of diffusion controlling curve and driving force controlling curve corresponding to the serving temperature. And then,high-temperature properties can be improved.

关键词： Single crystal superalloy Aging heat treatment γ' precipitation Kinetics

Measuring accessibility of bus system based on multi-source traffic data

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Geo-Spatial Information Science 2020年第3期23卷 248-257,I0005页

作者： Yufan Zuo Zhiyuan Liu xiao fu School of Transportation Southeast UniversityNanjingChina Jiangsu Key Laboratory of Urban ITS Jiangsu Province Collaborative Innovation Center of Modern Urban Traffic TechnologiesSoutheast UniversityNanjingChina

Accessibility is a representative indicator for evaluating the supply of bus *** studies have evaluated the accessibility from different *** the interaction among land use,bus timetable arrangement and individual factors,a more holistic accessibility measurement is proposed to combine static and dynamic characteristics from multisource traffic *** rationale of the proposed model is verified by a case study of bus system in Shenzhen,China,which is carried out to find the spatial and temporal discrepancy of service of bus *** is found that the adjustment of bus schedule to time-varying travel demand can affect accessibility of bus system and that Land-use development,average bus speed and bus facilities all have positive effects on accessibility of bus *** findings provide sig-nificant reference for transport planning and *** proposed model is not limited to accessibility measuring of bus system,but also applicable to other travel modes.

关键词： Accessibility bus system multi-source traffic data spatial-temporal distribution