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Modeling and realization of real time electronic countermeasure simulation system based on SystemVue

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Defence Technology（防务技术） 2020年第2期16卷 470-486页

作者： xiao-rong tong College of Computer Weinan Normal UniversityWeinan 714099China

In this paper,we proposed a new design scheme of real time electronic countermeasure simulation *** paper mainly expounds the modeling and realization methods of each part of the whole simulation system,and the real-time property of system has been *** countermeasure simulation system is the key part of military training of individuals;it can also allow the realistic evaluation of the performance of modern equipments and *** a proof,we have drawn up a series of simulation scenarios,such as radar electronic reconnaissance simulation scenario,to explain the feasibility and the superiority of our modeling scheme in this paper.

关键词： Electronic countermeasure system Real-time property System modeling SystemVue Simulation Signal processing Transparent computing

Eccentricity modulation of a close-in planet by a companion:Application to GJ 436 system

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Science China(Physics,Mechanics & Astronomy) 2009年第4期52卷 640-648页

作者： tong xiao ZHOU JiLin Department of Astronomy Nanjing UniversityNanjing 210093China

GJ 436b is a Neptune-size planet with 23.2 Earth masses in an elliptical orbit of period 2.64 days and eccentricity 0.16. With a typical tidal dissipation factor(Q′～106) as that of a giant planet with convective envelope,its orbital circularization timescale under internal tidal dissipation is around 1 Ga,at least two times less than the stellar age(> 3 Ga). A plausible mechanism is that the eccentricity of GJ 436b is modulated by a planetary companion due to their mutual perturbation. Here we investigate this possibility from the dynamical viewpoint. A general method is given to predict the possible locations of the dynamically coupled companions,including nearby/distance non-resonant or mean motion resonance orbits with the first planet. Applying the method to GJ 436 system,we find it is very unlikely that the eccentricity of GJ 436b is maintained at the present location by a nearby/distance companion through secular perturbation or mean motion resonance. In fact,in all these simulated cases,GJ 436b will undergo eccentricity damp and orbital decay,leaving the present location within the stellar age. However,these results do not rule out the possible existence of planet companions in nearby/distance orbits,although they are not able to maintain the eccentricity of GJ 436b.

关键词： celestial mechanics methods:analytical methods:N-body simulations stars:individual(GJ 436) planetary systems:dynamics

Metal-containing covalent organic framework:a new type of photo/electrocatalyst

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Rare Metals 2022年第4期41卷 1160-1175页

作者： xiao-tong Wang xiao-Feng Lin Ding-Shan Yu Key Laboratory for Polymeric Composite and Functional Materials Ministry of EducationSun Yat-Sen UniversityGuangzhou 510275China Key Laboratory of High Performance Polymer-based Composites Guangdong ProvinceSchool of ChemistrySun Yat-Sen UniversityGuangzhou 510275China School of Chemical Engineering and Light Industry Guangdong University of TechnologyGuangzhou 510006China

Metal-containing covalent organic frameworks(MCOFs),as a class of crystalline organic polymers with abundant single-atom metal sites,can respond effectively to various vital reactions,including hydrogen evolution reaction(HER),CO_(2) reduction reaction(CO_(2)RR),oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).The advent of MCOFs provides a platform for the establishment of model catalysts with highly repetitive structure to facilitate theoretical calculations and high-throughput screening while designing flexibility in mono-mer construction to lay the foundation for the development of highly selective and active photo/*** this review,we summarize the recent progress in this field and highlight several important MCOFs photo/electrocatalysts for OER,ORR,HER,and CO_(2)***,various approaches are also mentioned to improve or optimize the catalysts and indicate the future research direction on enhancing the performance of MCOFs catalysts based on the current existing challenges.

关键词： Covalent organic frameworks Hydrogen evolution reaction Carbon dioxide reduction reaction Oxygen reduction reaction Oxygen evolution reaction

Synthesis and Crystal Structure of a New Complex [CuL(Phen)]·NO_3

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1343-1346页

作者： QIU xiao-Hang ZHAO Jun tong xiao-Lan Department of Chemistry Nankai University Tianjin 300071 China

A new mononuclear copper（Ⅱ） complex [CuL（Phen）]-NO3 （L - 2-{2-[（3,5-dibro- mosalicylidene）amino]ethyl }- 1 H- 1,3-benzimidazole, Phen = 1,10-phenanthroline） has been synthesized and its crystal structure was determined by X-ray diffraction method. It crystallizes in monoclinic, space group C2/c with a = 24.966（7）, b = 15.673（4）, c = 16.600（5） A,β = 123.981（4）°, C28H20Br2CuN604, Mr = 727.86, V = 5386（2） A^3, Z = 8, Dc = 1.795 g/cm^3,μ（MoKα = 3.826 mm^-1, F（000） = 2888, the final R = 0.0508 and wR = 0.1024 for 5440 independent reflections with Rint = 0.1134. The title compound is composed of [CuL（Phen）]＋ cation and NO3^- anion. The coordination geometry around copper atom is a highly distorted trigonal bipyramid consisting of one benzimidazole nitrogen atom, one phenolato oxygen atom and one phenanthroline nitrogen atom on the equatorial plane together with one imine nitrogen atom and one phenanthroline nitrogen atom occupying the axial positions. The hydrogen bonding and π-π stacking interactions link the copper complex molecules into a 3-D supramolecular structure.

关键词： crystal structure copper complex 1,10-phenanthroline hydrogen bonds

Particle stratification and penetration of a linear vibrating screen by the discrete element method

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International Journal of Mining Science and Technology 2012年第3期22卷 357-362页

作者： xiao Jianzhang tong Xin School of Mechanical Engineering and Automation Huaqiao University Xiamen 361021 China

A simulation of stratification and penetration was performed over a range of structural parameters that included screen width, aperture size, inclination angle, and wire diameter. The discrete element method （DEM） was used for the simulations. The terms stratification and penetration are defined and the change in fine panicle concentration is discussed. Mathematical models relating fine particle ratio to time are established using the least squares method. The effect of structural parameters on fine panicle ratio is analyzed. Stratification and penetration rate are discussed by considering the time derivative of the fine panicle ratio. The conclusions are： an increase in inclination or wire diameter has a positive effect on par- ticle stratifying; The optimal screen width is 40 mm for panicle stratification; The inclination angle has a negative effect on the penetration; The effect of wire diameter and screen width on the penetration rate is negligible.

关键词： Fine particle ratioStratificationPenetrationStructural parameter

ITO thin films prepared by electron beam evaporation with End-Hall ion source assisted without heating to the substrate

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光学精密工程 2005年第4期13卷 397-402页

作者： GAO Jin-song XU Ying WANG xiao-yi WANG tong-tong Optical Technology and Research Center Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130022 China

ITO （indium oxide doped with tin） thin films were deposited on glass substrates by using ITO pellet with a composition of w（In2O3）=90% and w（SnO2）=10% by electron beam evaporated with End-Hall ion source assisted without extra heating. The rate of deposition and flow rate of oxygen were measured and changed to obtain the best properties of ITO thin films. Furthermore, the post annealing process was done in vacuum at different annealing temperatures for 2 h and at 400℃ for different keeping time, respectively. The relation between optical, electrical properties and structure was discussed in detail.

关键词： ITO 薄膜电子束离子源

Measurement and characterization of bulk nanobubbles by nanoparticle tracking analysis method

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Journal of Hydrodynamics 2022年第6期34卷 1121-1133页

作者： xiao-tong Ma Ming-bo Li Chao Sun Center for Combustion Energy Key Laboratory for Thermal Science and Power Engineering of Ministry of EducationDepartment of Energy and Power EngineeringTsinghua UniversityBeijing100084China

The size of the bulk nanobubbles(typically 100 nm-200 nm in diameter)is below the optical resolution of the typical microscopes,which makes it difficult to make a direct observation of them and differentiate between the nanoparticles and the *** this work,a nanoparticle tracking analysis(NTA)system is developed for tracking and sizing the bulk nanobubbles,and more broadly,the Brownian diffusing *** demonstrate the capabilities of the NTA in characterizing the nanoparticles through systematic validation of accuracy and *** particularly exhibit its unique advantages in detecting the polydisperse nanoparticle *** the nucleation and the thermodynamic stability of the bulk nanobubbles are systematically studied by the NTA *** bulk nanobubbles smaller than 600 nm in size are generated via the ultrasonication *** is shown that both the ultrasonic cavitation treatment time and amplitude,essentially,the energy input,favor the nucleation of the bulk nanobubbles with a more concentrated size distribution,a higher concentration,and a smaller hydrodynamic *** temperature dependence of the bulk nanobubbles over a wide range from 25°C to 70°C is *** is found that the nanobubble first shrinks in size significantly and then the size keeps approximately constant with the increasing temperature,showing a narrow size *** transition temperature is around 45°***,as an open system,the NTA is a potential tool in the study of the dynamic behavior of the bulk nanobubbles in situ,such as the coalescence and the collapse.

关键词： Nanoparticle tracking analysis bulk nanobubble light scattering hydrodynamic size number concentration

Worst-Case Finish Time Analysis for DAG-Based Applications in the Presence of Transient Faults

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Journal of Computer Science & Technology 2016年第2期31卷 267-283页

作者： xiao-tong Cui Kai-Jie Wu tong-Quan Wei Hsing-Mean Sha Key Laboratory of Dependable Service Computing in Cyber Physical Society Chongqing University Chongqing 400014 China College of Computer Science Chongqing University Chongqing 400044 China Department of Computer Science and Technology East China Normal University Shanghai 200241 China

Tasks in hard real-time systems are required to meet preset deadlines, even in the presence of transient faults and hence the analysis of worst-case finish time （WCFT） must consider the extra time incurred by re-executing tasks that were faulty. Existing solutions can only estimate WCFT and usually result in significant under- or over-estimation. In this work, we conclude that a sufficient and necessary condition of a task set experiencing its WCFT is that its critical task incurs all expected transient faults. A method is presented to identify the critical task and WCFT in O（IVI ＋ IEI） where IVI and IEI are the number of tasks and dependencies between tasks, respectively. This method finds its application in testing the feasibility of directed acyclic graph （DAG） based task sets scheduled in a wide variety of fault-prone multi-processor systems, where the processors could be either homogeneous or heterogeneous, DVS-capable or DVS-incapable, etc. The common practices, which require the same time complexity as the proposed critical-task method, could either underestimate the worst case by up to 25%, or overestimate by 13%. Based on the proposed critical-task method, a simulated-annealing scheduling algorithm is developed to find the energy efficient fault-tolerant schedule for a given DAG task set. Experimental results show that the proposed critical-task method wins over a common practice by up to 40% in terms of energy saving.

关键词： fault tolerance worst-case analysis simulated annealing energy conservation dynamic voltage scaling (DVS)

Squeezing Transformation of Three-Mode Entangled State

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Communications in Theoretical Physics 2005年第5X期44卷 911-916页

作者： QIAN xiao-Qing SONG tong-Qiang Department of Physics Ningbo University Ningbo 315211 China

We introduce the three-mode entangled state and set up an experiment to generate it. Then we discuss the three-mode squeezing operator squeezed ｜p, X2, X3〉→μ^-3/2｜p/μ, X2/μ, X3/μ） and the optical implement to realize such a squeezed state. We also reveal that c-number .asymmetric shrink transform in the three-mode entangled state, i.e. ｜p, X2,X3）→μ^-1/2｜p/μ, X2,X3）, maps onto a kind of one-sided three-mode squeezing operator {iλ （∑i^3=1 Pi）（∑i^3=1 Qi） -λ/2}. Using the technique of integration within an ordered product （IWOP） of operators, we derive their normally ordered forms and construct the corresponding squeezed states.

关键词： three-mode entangled state c-number asymmetric shrink transform one-sided three-mode squeezing operator