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IMPROVEMENT ON STABIlITY OF ADAPTIVE NOISE CONTROl SYSTEM BY USE OF GRADIENT BACK-ADJUSTING FlMS AlGORITHM

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Chinese Journal of Mechanical Engineering 1997年第4期10卷 19-23页

作者： lü guangqing Chen Hualing Huang Xieqing Zhang Shengbi Xi’an Jiaotong University

GBFlMS algorithm is posed to improve the stability and performance on noise reduction of adaptive noise control (ANC) system. Theoretical analysis shows that stability and precision in convergence of FlMS algorithm can be improved by GBFlMS. By iterative calculation of back adjusting g radient, the calculating operation of GBFlMS can be nearly the same as that of FlMS. An ANC system with GBFlMS has good behavior for noise reduction of compressor chamber on refrigerator. At the port of heat dissipation, noise level has been reduced 20 dB, about double of that got by the system with FlMS.

关键词： Noise Control Adaptability Refrigerator

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机械装配耦合动刚度的逆子结构辨识方法

机械工程学报 2016年第9期52卷 86-95页

作者：吕广庆仪垂杰方科暨南大学教育部重大工程灾害与控制重点实验室广州510632 青岛理工大学机械工程学院青岛266033

为检测机械装配的动态质量,基于子结构法分析装配工艺对部件动态传递特性的影响作用,明确装配耦合动刚度是影响机械装配动态质量的唯一决定性关键因素。在阐述装配耦合动刚度的直接逆子结构辨识方法(直接法)并分析其在生产实践应用中存... 详细信息

为检测机械装配的动态质量,基于子结构法分析装配工艺对部件动态传递特性的影响作用,明确装配耦合动刚度是影响机械装配动态质量的唯一决定性关键因素。在阐述装配耦合动刚度的直接逆子结构辨识方法(直接法)并分析其在生产实践应用中存在的缺陷之后,建立五类装配耦合动刚度的基于频率响应函数(Frequency response function,FRF)谱的间接逆子结构辨识方法(间接法),并给出单点耦合和多点耦合计算公式及其工程适用条件。分析表明,五类间接法完全或部分避免直接法存在的测试操作困难,第一类间接法辨识精度受FRF谱测量误差影响最低且与直接法相近,可作为机械装配耦合动刚度辨识的最优间接法选项。逆子结构辨识方法的理论完备性和第一类间接法的应用有效性分别经机械装配二级子结构集总参数模型及其类比试验模型予以检验,为机械装配耦合动刚度辨识及其动态质量检测提供新的有效技术方法。

关键词：机械装配耦合动刚度逆子结构辨识频率响应函数

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机械装配动态质量的子结构分析与量化计算

机械科学与技术 2016年第6期35卷 840-845页

作者：吕广庆方科庞冬梅暨南大学重大工程灾害与控制教育部重点实验室广州510632

机械装配作为机电产品生产制造的重要工艺,直接影响产品整体动态质量。现有机械装配质量检测分析主要集中在"静态质量",如尺寸协调性与形位公差等,而机械装配本身还具有动态质量,机械装配检测评价只关注其静态质量有失全面。在诠释"机... 详细信息

机械装配作为机电产品生产制造的重要工艺,直接影响产品整体动态质量。现有机械装配质量检测分析主要集中在"静态质量",如尺寸协调性与形位公差等,而机械装配本身还具有动态质量,机械装配检测评价只关注其静态质量有失全面。在诠释"机械装配动态质量"的概念之后,基于子结构分析方法明确界定了机械装配动态传递特性函数关系,并采用本征值分析方法讨论了机械装配工艺对装配子结构部件和装配件系统的动态传递特性的影响作用。进而采用测量的频率响应函数(frequency response function,FRF)计算机械装配比率矩阵的本征值,并用其均值对机械装配动态质量进行量化计算。基于两部件机械装配的"二级子结构"集总参数模型和应用实例模型,检验了相关分析结论和所建立的量化计算方法。研究结果有助于完善现有机械装配质量检测评价技术理论。

关键词：机械装配动态质量子结构分析量化计算装配比率矩阵

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天津市经济-生态-能源耦合协调关系研究

无锡商业职业技术学院学报 2020年第6期20卷 1-6页

作者：赵慧卿吕广庆天津商业大学经济学院天津300134

为考察天津市经济与生态、能源之间的协调关系,构建了包括3个一级指标、20个基础指标的评价指标体系,运用反熵法确定权数,对天津市2010—2018年经济-生态-能源系统进行综合评价。在此基础上,对天津市经济-生态-能源耦合协调度及相对发... 详细信息

为考察天津市经济与生态、能源之间的协调关系,构建了包括3个一级指标、20个基础指标的评价指标体系,运用反熵法确定权数,对天津市2010—2018年经济-生态-能源系统进行综合评价。在此基础上,对天津市经济-生态-能源耦合协调度及相对发展度进行分析。结果表明:研究期内,天津市生态、经济、能源综合发展水平持续提升;三者之间耦合度处于较高水平,但耦合协调度相对较差,一度处于濒临失调阶段;生态与经济、能源与经济相对发展度大致在“滞后”和“同步”间交替,总体来说呈上升趋势。未来天津市应该注重经济与生态、能源之间的协调发展,提升经济发展质量。

关键词：反熵法综合评价耦合协调度相对发展度

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包装工程专业本科教育中产学研的结合

包装学报 2014年第2期6卷 80-83页

作者：林勤保吕广庆暨南大学包装工程研究所广东珠海519070 暨南大学产品包装与物流广东省高校重点实验室广东珠海519070

包装工程本科教育中产学研相结合的问题,存在不同的层次,侧重点也不相同。包装工程本科教育与包装产业结合的主要方式有认识实习、生产实习、设计大赛、校企科研合作、课外导师制、开设与生产实践相关的选修课、生产实践人员进课堂、设... 详细信息

包装工程本科教育中产学研相结合的问题,存在不同的层次,侧重点也不相同。包装工程本科教育与包装产业结合的主要方式有认识实习、生产实习、设计大赛、校企科研合作、课外导师制、开设与生产实践相关的选修课、生产实践人员进课堂、设置专项奖助学金等;学校教育之间的合作也是产学研结合的重要组成部分,学生的思想素养以及教师的职业道德,对产学研结合的实践效果和可持续发展具有直接影响;包装工程本科教育还需与科学研究相结合,以培养学生的科学思维能力,包装工程专业教师也应不断提高科研水平,以满足持续发展的本科教育需求。

关键词：包装工程专业本科教育产学研结合

A finite-time 3D guidance law based on fixed-time convergence disturbance observer

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Chinese Journal of Aeronautics 2020年第4期33卷 1299-1310页

作者： Feng YANG guangqing XIA State Key laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116024China Key laboratory of Advanced Technology for Aerospace Vehicles of liaoning Province Dalian University of TechnologyDalian 116024China School of Aeronautics and Astronautics Dalian University of TechnologyDalian 116024China

In order to achieve accurate interception of high-speed maneuvering targets,this paper presents a relative line-of-Sight(lOS)velocity based finite-time three-dimensional guidance law design framework,and discusses the application of fixed-time convergence disturbance observer in this ***,a simple lyapunov function is provided to show that the coupled terms in the relative kinematics can be ignored in the proposed guidance law design ***,the realizations of several classical guidance laws are analyzed with the proposed framework,including TPN guidance law,finite-time Input-to-State Stability(ISS)guidance law,and sliding mode guidance ***,fixed-time convergence disturbance observers are introduced to design the composite finite-time 3D guidance law,and lyapunov method is employed to show the stability of the guidance *** simulations with different scenarios show that the proposed generalized guidance law performs high interception accuracy.

关键词： Disturbance Finite-time stability Fixed-time stability Guidance law Observer

Investigation into the transient flow characteristics of noble gas propellants using the pulsed inductive discharge in electric propulsion

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Chinese Journal of Aeronautics 2020年第9期33卷 2329-2341页

作者： Yuguo CHENG guangqing XIA PlA 91550 Element 41 Dalian 116023China State Key laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116024China Key laboratory of Advanced Technology for Aerospace Vehicles of liaoning Province Dalian University of TechnologyDalian 116024China

The Pulsed Inductive Thruster(PIT)has the advantages of repeatable startup,no corruption and in-situ propellant *** study the flow expansion and circuit characteristics of PITs,the circuit-fluid model is developed,and the high temperature thermodynamic and transport models are combined with the circuit-fluid model to predict the critical plasma *** flow fields of initial mass of 2–8 mg and charge voltages of 10–14 k V are *** of the flow fields of argon and helium propellants suggests that,the flow field structures are *** differences exist on the magnitude of the density and magnetic field,caused by larger velocity in lighter atom case and difference on the ionization gap between adjacent ionization *** of the circuit characteristics by the two-dimensional results indicates that the ratio of coil inductance to circuit inductance affects both the rise rate and phase of the plasma current,the larger the ratio,the greater the rise rate and the better the following *** calculations show that the magnetic energy obtained within the decoupling distance determines the overall performance the thruster can be obtained;self-induced field maintained by the thermal motion after the main pulse leads to the long attenuation process and difference on the total impulse when the angle of conical pylon is varied under constant coil dimension.

关键词： Argon and helium propellants Circuit characteristics Circuit-fluid model Flow properties Pulsed inductive thruster

Simulation of plasma behavior for medium propellant mass and pulsed energy of small scale pulsed inductive thruster

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Chinese Journal of Aeronautics 2020年第1期33卷 176-190页

The pulsed inductive thruster is characterized of no electrode corruption and wide propellant *** give insight into the propulsion mechanism of small scale thruster at different propellant mass(m)and energy(E)levels,the transient Magneto Hydro Dynamics(MHD)method,completed by high temperature thermodynamic and transport,and plasma electrical models,is developed to study argon plasma response under the excitation of current of high rise *** calculating the two-dimensional expansion properties of the thruster with conical pylon,the simulations find that the main energy deposition occurs during the initial pulse rise stage,and the energy density of Joule heat is two magnitudes higher than the deposition in the down *** propellant mass of 2 mg,average axial velocity of the current sheet increases from about 15 km/s at 750 J to about 21 km/s at 1470 J within the decoupling *** velocity variation synchronizes with the pulsed rise in the *** monotonically decrease of the temperature along axis results in the growth of low ionization level ions and reducing of high *** current sheet maintains the structure formed during the initial pulse rise when moving beyond the decoupling *** the change in forward velocity,the main difference is the dimension compared with that in the first half period,caused by thermal conduction and particle *** variations of total impulse It in the range of m from 2 mg to8 mg and E from 750 J to 1470 J show that It is proportional to m1/2 when E is determined.

关键词： Expansion properties Flow field Magneto Hydro Dynamics(MHD)method Pulsed inductive plasma Total impulse

Monocyte subsets and their differentiation tendency after burn injury

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Frontiers of Medicine 2013年第4期7卷 397-400页

作者： guangqing Wang Zhaofan Xia Burn Surgery Changhai HospitalSecond Military Medical UniversityShanghai 200433China

Monocytes are critical effectors and regulators of immune *** the nomenclature of monocyte subsets may be beneficial for understanding the complex function of monocytes in steady and inflammatory states.A monocyte has the potential to differentiate into dendritic cells or macrophages,and this behavior significantly changes in severely burned patients and *** findings in the present study may help enhance understanding on the perturbation of the immune system after severe burn injury.

关键词： monocyte differentiation burn