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MATheMATICAL BACKGROUND AND PIVOTAL TECHNOLOGIES FOR REALIZATION OF RADAR PPI SIMULATION BY MEANS OF PERSONAL COMPUTER’S CRT DISPLAY

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MATHEMATICAL BACKGROUND AND PIVOTAL TECHNOLOGIES FOR REALIZA...

亚州仿真会议暨第五届系统仿真和科学计算国际会议

作者： Li jian gong jianhua he Hong Yin Quanliang Zhengzhou Air Defense Forces Academy Zhengzhou Post Code 450052 P.R.China

The present paper analyzes the mathematical background and pivotal technologies for realization of radar PPI simulation by means of personal computer’s CRT display based on the sound mastery of the

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基于仿人智能控制的四旋翼飞行控制器设计

计算机仿真 2017年第4期34卷 95-99,275页

作者：雷建和宫汝林刘明胡廷轩青岛理工大学自动化工程学院山东青岛266520 中国科学院合肥智能机械研究所安徽合肥230031

四旋翼飞行器的姿态控制是其稳定飞行的基础。传统PID控制算法在四旋翼飞行器的姿态控制中往往存在参数适应性差的缺点,仿人智能控制(HSIC)可以通过特征辨识对系统采取不同的控制模态,调整控制参数,很好地解决传统PID控制算法的缺点。... 详细信息

四旋翼飞行器的姿态控制是其稳定飞行的基础。传统PID控制算法在四旋翼飞行器的姿态控制中往往存在参数适应性差的缺点,仿人智能控制(HSIC)可以通过特征辨识对系统采取不同的控制模态,调整控制参数,很好地解决传统PID控制算法的缺点。依据仿人智能控制(HSIC)理论,设计一种四旋翼飞行器姿态控制器,并对相关参数进行简化,通过在MATLAB中对四旋翼飞行器进行建模仿真,并与传统的PID控制器进行比较,验证了上述控制器的稳定性、抗干扰性和鲁棒性,结果表明上述控制器的控制性能更好,结构简单且响应速度更快、抗干扰性和鲁棒性更强。

关键词：四旋翼飞行器仿人智能控制飞行控制参数简化

An Improved Result for Positive Measure Reducibility of Quasi-periodic Linear Systems

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Acta Mathematica Sinica,English Series 2006年第1期22卷 77-86页

作者： Hai Long he jian gong YOU Department of Mathcmatics Nanjing University Nanjing 210093 P. R. China

In this paper, by the KAM method, under weaker small denominator conditions and nondegeneracy conditions, we prove a positive measure reducibility for quasi-periodic linear systems close to constant： X = （A（λ）＋ F（ψ, λ））X, ψ=ωwhere the parameter λ∈ （a, b）, w is a fixed Diophantine vector, which is a generalization of jorba ＆ Simo＇s positive measure reducibility result.

关键词： Quasi-periodic Reducibility KAM Non-degeneracy

基于瞬态动力学的数控转塔冲床床身动力学研究

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机械工程与自动化 2017年第1期 74-76页

作者：高健翔高建和龚俊杰韦源源扬州大学广陵学院江苏扬州225127 扬州大学机械工程学院江苏扬州225127

为了研究数控转塔冲床床身的动力学特性,利用有限元分析软件ANSYS Workbench对床身进行瞬态动力学分析,并与实验数据进行分析对比,验证床身动力学模型。在得到准确动力学模型的基础上对床身进行振动控制研究,并引入阻尼结构进行床身振... 详细信息

为了研究数控转塔冲床床身的动力学特性,利用有限元分析软件ANSYS Workbench对床身进行瞬态动力学分析,并与实验数据进行分析对比,验证床身动力学模型。在得到准确动力学模型的基础上对床身进行振动控制研究,并引入阻尼结构进行床身振动吸收。

关键词：数控转塔冲床床身瞬态动力学分析阻尼结构

The Mechanism of heating Rate on the Secondary Recrystallization Evolution in Grain Oriented Silicon Steel

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期 275-282页

作者：高倩 LI Jun WANG Xianhui CAO Laifu gong jian LI Bo Central Iron and Steel Research Institute Group Shougang Zhixin Electromagnetic Material R&D (Beijing) Co. Ltd. Beijing Shougang Co. Ltd.

Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing, in which the evolution of magnetic properties, grain orientations and precipitates were studied. To illustrate the Zener factor, the diameter and number density of precipitates of interrupted testing samples were statistically calculated. The effect of precipitate ripening on the Goss texture and magnetic property was investigated. Data indicated that the trend of Zener factor was similar under different heating rates, first increasing and then decreasing, and that the precipitate maturing was greatly inhibited as the heating rate increased. Secondary recrystallization was developed at the temperature of 1 010 ℃ when a heating rate of 5 ℃/h was used, resulting in Goss, Brass and {110} oriented grains growing abnormally and a magnetic induction intensity of 1.90T. Furthermore, increasing the heating rate to 20 ℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss texture. However, when the heating rate was extremely fast, such as 40 ℃/h, poor secondary recrystallization was developed with many island grains, corresponding to a decrease in magnetic induction intensity to 1.87 T. At a suitable heating rate of 20 ℃/h, the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1 020 ℃ were found among the experimental variables in this study. The heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates, leading to the deviation and dispersion of Goss texture, thereby reducing the magnetic properties.

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Numerical simulation of 3D electromagnetic–thermal phenomena in an induction heated slab

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Journal of Iron and Steel Research International 2020年第4期27卷 420-432页

作者： he-ping Liu Xian-hui Wang Liang-ying Si jian gong Central Iron and Steel Research Institute Beijing 100081China Shougang Zhixin Qian’an Electromagnetic Material Co. Ltd.Qian’an 064404HebeiChina

A mathematical model was developed to get an insight into 3D electromagnetic–thermal phenomena in an induction heated steel slab with a large width/thickness ratio by solving a fully coupled Maxwell equations and energy conservation *** spatial heat radiation between the slab surface and the refractory wall in an induction furnace was *** electromagnetic induction and temperature distribution features inside the slab with time evolution were *** effects of electromagnetic induction parameters,thermal conductivity of the material and process parameters on the induction heating process were theoretically *** results show that the spatial distribution of induction heat generation inside the slab is *** high work frequency and the low heat conductivity of slab increase the non-uniformity of slab induction heating *** radiative heat loss and heat transfer between the slab and the metal parts used for holding the slab have an important effect on the slab surface *** is necessary to separately control the current input in the multi-layer coil windings along the height direction of furnace and adopt the multi-step heating strategies with time evolution to improve the homogenization of the slab temperature.

关键词： Slab Electromagnetic feld Induction heating Numerical simulation

ON ACOUSTIC PERFORMANCE OF MEASURING STRUCTURE FOR CAVITATION NOISE

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Journal of Hydrodynamics 1991年第2期3卷 42-50页

作者： Wu, jian-hua Chai, gong-chun Wang, he-sheng Nanjing Hydraulic Research Inst Nanjing China

The acoustic performance of the structure for measuring cavitation noise is theoretically analysed, and two judging criteria of the acoustic performance of STW (sound transmission window) are presented in this paper. One is of impedance matching between working liquid and STW:ρ1C1 = ρ2C2. The other is of maximum frequency (or minimum wave length) of cavitation noise spectrum: fmax&le c/60D (or λmin/D ≥ 60). If either of the criteria is met reliable measured results of cavitation noise will be obtained. The theoretical results are verified through experiments. According to the criteria, the paper analyses the acoustic performance of routinely used plexiglass STW. The results show that in the research of clear water cavitation the impedance ratio, 2. 18, does not satisfy ρ1C1 = ρ2C2, and fmax&le C/60D hardly holds for actual cavitation noise spectrum. Therefore, plexiglass STW is not good enough for sound transmission. From this point of view, polyethylene is better sound transmission material than plexiglass.

关键词： Acoustic Waves Transmission Glass Acoustic Properties Hydrodynamics Fluid Structure Interaction Polyethylenes Acoustic Properties Water Waves

Artificial Sun synchronous frozen orbit control scheme design based on J_2 perturbation

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Acta Mechanica Sinica 2011年第5期27卷 809-816页

作者： gong-Bo Wang Yun-he Meng Wei Zheng Guo-jian Tang College of Aerospace and Material Engineering National University of Defense Technology410073 Changsha China

Sun synchronous orbit and frozen orbit formed due to J 2 perturbation have very strict constraints on orbital parameters,which have restricted the application a *** this paper,several control strategies were illustrated to realize Sun synchronous frozen orbit with arbitrary orbital elements using continuous ***,according to mean element method,the averaged rate of change of the orbital elements,originating from disturbing constant accelerations over one orbital period,was derived from Gauss＇ variation of parameters ***,we proposed that binormal acceleration could be used to realize Sun synchronous orbit,and radial or transverse acceleration could be adopted to eliminate the rotation of the argument of the ***,amending methods on the control strategies mentioned above were presented to eliminate the residual secular *** results showed that the control strategies illustrated in this paper could realize Sun synchronous frozen orbit with arbitrary orbital elements,and can save much more energy than the schemes presented in previous studies,and have no side effect on other orbital parameters＇ secular motion.

关键词： Continuous low-thrust Artificial Sun synchronous orbit Artificial frozen orbit Gauss' variation of parameters equations Mean element method

Central nervous system injury meets nanoceria:opportunities and challenges

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Regenerative Biomaterials 2022年第1期9卷 1001-1017页

作者： Wang Yang Maoting Zhang jian he Mingfu gong jian Sun Xiaochao Yang School of Biomedical Engineering and Medical Imaging Army Medical UniversityChongqing 400038China Army health Service Training Base Army Medical UniversityChongqing 400038China Xinqiao Hospital Army Medical UniversityChongqing 400038China

Central nervous system(CNS)injury,induced by ischemic/hemorrhagic or traumatic damage,is one of the most common causes of death and long-term disability *** oxygen and nitrogen species(RONS)resulting in oxidative/nitrosative stress play a critical role in the pathological cascade of molecular events after CNS ***,by targeting RONS,antioxidant therapies have been intensively explored in previous ***,traditional antioxidants have achieved limited success thus far,and the development of new antioxidants to achieve highly effective RONS modulation in CNS injury still remains a great *** the rapid development of nanotechnology,novel nanomaterials provided promising opportunities to address this *** these,nanoceria has gained much attention due to its regenerative and excellent RONS elimination *** promote its practical application,it is important to know what has been done and what has yet to be *** review aims to present the opportunities and challenges of nanoceria in treating CNS *** physicochemical properties of nanoceria and its interaction with RONS are *** applications of nanoceria for stroke and neurotrauma treatment are *** possible directions for future application of nanoceria in CNS injury treatment are proposed.

关键词： nanoceria reactive oxygen species central nervous system injury stroke neurotrauma