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Recent active thermal management technologies for the development of energy-optimized aerospace vehicles in China

Chinese Journal of Aeronautics 2021年第2期34卷 1-27页

作者： Jixiang WANG Yunze LI xiangdong liu Chaoqun SHEN Hongsheng ZHANG Kai XIONG College of Electrical Energyand Power EngineeringYangzhou UniversityYangzhou 225009China School of Aeronautic Science and Engineering Beihang UniversityBeijing 100083China Institute of Engineering Thermophysics North China University of Water Conservancy and Electrical PowerZhengzhou 450045China HiWING General Aviation Equipment Corporation Limited Beijing 100074China School of Mechanical Engineering and Automation Harbin Institute of TechnologyShenzhen Graduate SchoolShenzhen 518117China

Recently, the development of modern vehicles has brought about aggressive integration and miniaturization of on-board electrical and electronic devices. It will lead to exponential growth in both the overall waste heat and heat flux to be dissipated to maintain the devices within a safe temperature range. However, both the total heat sinks aboard and the cooling capacity of currently utilized thermal control strategy are severely limited, which threatens the lifetime of the on-board equipment and even the entire flight system and shrink the vehicle’s flight time and range. Facing these thermal challenges, the USA proposed the program of "INVENT" to maximize utilities of the available heat sinks and enhance the cooling ability of thermal control strategies. Following the efforts done by the USA researchers, scientists in China fought their ways to develop thermal management technologies for Chinese advanced energy-optimized airplanes and spacecraft. This paper elaborates the available on-board heat sinks and aerospace thermal management systems using both active and passive technologies not confined to the technology in China. Subsequently, active thermal management technologies in China including fuel thermal management system, environment control system, non-fuel liquid cooling strategy are reviewed. At last, space thermal control technologies used in Chinese Space Station and Chang’e-3 and to be used in Chang’e-5 are *** issues to be solved are also identified, which could facilitate the development of aerospace thermal control techniques across the world.

关键词： Aerospace engineering Efficiency promotion Fluid dynamics Heat and mass transfer Thermal management

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Distributed vibration control of a large solar power satellite

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Astrodynamics 2019年第2期3卷 189-203页

作者： Enmei Wang Shunan Wu Yufei liu Zhigang Wu xiangdong liu School of Aeronautics and Astronautics Dalian University of TechnologyDalian 116024China Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijing 100094China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116024China School of Automation Bejing Institute of TechnologyBejing 100081China

To deal with the vibration problem of the solar power satellite(SPS),the distributed vibration control approach is investigated in this *** the Multi-Rotary joints SPS as the research objective,the control unit(CU)and the location relationship matrix are rstly de ned for distributed controller design according to the con guration of *** dynamic model of each CU is therefore established based on the nite element *** dynamic model of the whole SPS structure is then developed using the CU models,and is updated along with on-orbit *** distributed cooperative controller,using proportional and di erential feedback and the interaction feedback among adjacent CUs,is proposed to suppress *** close-loop distributed cooperative control system is then achieved by integrating all distributed controllers,and the asymptotic stability is proofed by the Lyapunov's stability *** verify the feasibility of the proposed control system,three numerical cases are nally *** results demonstrate that the distributed cooperative controllers can e ectively suppress vibration during on-orbit assembly and operation after assembly,and the closed-loop system has good fault tolerance.

关键词： solar power satellite vibration control distributed control on-orbit assembly

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A Class of Jump-Diffusion Stochastic Differential System Under Markovian Switching and Analytical Properties of Solutions

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Journal of Systems Science and Information 2020年第1期11卷 17-32页

作者： xiangdong liu Zeyu MI Huida CHEN Department of Statistics Jinan UniversityGuangzhou 510632China

Our article discusses a class of Jump-diffusion stochastic differential system under Markovian switching(JD-SDS-MS).This model is generated by introducing Poisson process and Markovian switching based on a normal stochastic differential *** work dedicates to analytical properties of solutions to this ***,we give some properties of the solution,including existence,uniqueness,non-negative and global ***,boundedness of first moment of the solution to this model is ***,properties about coefficients of JD-SDS-MS is proved by using a right continuous markov ***,we study the convergence of Euler-Maruyama numerical solutions and apply it to pricing bonds.

关键词： stachastic differential system Markovian switching jump-diffusion analytical properties numerical solutions

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A novel global sliding mode control strategy for attitude control of reusable launch vehicles in the reentry phase 36

A novel global sliding mode control strategy for attitude co...

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第36届中国控制会议

作者： Liang Wang Yunpeng liu xiangdong liu Beijing Aerospace Automatic Control Institute School of Automation Beijing Institute of Technology

ISBN: (纸本)9781538629185

The attitude control for reusable launch vehicles（RLV） is responsible for the robust operation to avoid the major deterioration from uncertainties of parameters and external disturbances in the reentry *** for these practical issues with the study of the feedback-linearized RLV rotational equations of motion,two global sliding mode control（SMC） strategies are proposed with modified PID-type sliding ***,this paper begins with a SMC method,which is applied with a modified fixed-gain PID-type sliding surface so that it achieves a global sliding mode and guarantees the global robustness of the controlled ***,in order to rationally deal with the contradictory relationship between faster response and smaller overshoot,an improved SMC method is derived with modified variable-gain PID-type sliding ***,the effectiveness of the proposed strategies is verified by the theoretical analysis and simulation results are presented for the attitude control problem of X-33 RLV in the reentry phase.

关键词： Attitude control Reusable launch vehicles Global robustness Sliding mode control PID-type sliding surface

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Tilted Angle Implantation of Xe Ions in potassium Titanyl Phosphate

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Chinese Physics Letters 1991年第5期8卷 244-247页

作者： WANG Keming SHI Borong WANG Zhonglie ZHAO Qingtai liu xiangdong liu Jitian liu Yaogang Department of Physics Shandong UniversityJinan 250100 Institute of Crystal Material Shandong UniversityJinan 250100

200keV Xe ions were implanted in potassium titanyl phosphate(KTP)at deferent angles:0°,45°and 60°.The lateral spread of Xe ions in KTP was studied by Rutherford backscattering of 2.1 MeV He *** result is compared w... 详细信息

关键词： prediction potassium KTP

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Practical Tracking Method based on Best Buddies Similarity

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Cyborg and Bionic Systems 2023年第1期4卷 136-148页

作者： Haiyu He Zhen Chen Haikuo liu xiangdong liu Youguang Guo Jian Li School of Automation Beijing Institute of TechnologyBeijingChina School of Mechatronical Engineering Beijing Institute of TechnologyBeijingChina School of Electrical and Data Engineering University of Technology SydneySydneyAustralia

Visual tracking is a crucial skill for bionic robots to perceive the environment and control their ***,visual tracking is challenging when the target undergoes nonrigid deformation because of the perspective change from the camera mounted on the *** this paper,a real-time and scale-adaptive visual tracking method based on best buddies similarity(BBS)is presented,which is a state-of-the-art template matching method that can handle nonrigid *** proposed method improves the original BBS in 4 aspects:(a)The caching scheme is optimized to reduce the computational overhead,(b)the effect of cluttered backgrounds on BBS is theoretically analyzed and a patch-based texture is introduced to enhance the robustness and accuracy,(c)the batch gradient descent algorithm is used to further speed up the method,and(d)a resample strategy is applied to enable the BBS to track the target in scale *** proposed method on challenging real-world datasets is evaluated and its promising performance is demonstrated.

关键词： handle template mounted

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Controlled preparation of PAMS hollow core microcapsules with high uniformity and its application in the production of GDP fuel capsules for ICF engineering

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Fundamental Research 2023年第4期3卷 602-610页

作者： Qiang Chen Meifang liu xiangdong liu Bo Li Yongping Chen Laser Fusion Research Center China Academy of Engineering PhysicsMianyang 621900China Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096China

Uniform poly-α-methylstyrene(PAMS)hollow core microcapsules(HCMs)are widely used as templates to fabricate glow discharge polymer(GDP)fuel capsules,which are fundamental devices for inertial confinement fusion(ICF)*** sphericity and surface finish uniformity of PAMS HCMs are critical for achieving highquality GDP fuel *** this work,millimeter-scale PAMS HCMs were fabricated by a microencapsulation *** sphericity and surface finish uniformity were concurrently improved using di-t-butyl peroxide(DTBP).The mechanisms of these effects were also experimentally and theoretically *** results show that DTBP distributes at the O-W2 interface of W1/O/W2 compound droplets,which resists the diffusion of molecules through the O-W2 interface *** resisted diffusion of H_(2)O molecules into the O phase eliminates PAMS HCM surface ***,the resistance of fluorobenzene(FB)molecules from diffusing from the O phase into the W2 phase can effectively extend the solidification of W1/O/W2 compound droplets and thus improve the spherical uniformity of the *** these improved PAMS HCMs,GDP fuel capsules meeting the stringent requirements for ICF engineering are prepared,and the quality of which is beyond the National Ignition Facility standard.

关键词： Inertial confinement fusion engineering Mass transfer regulation PAMS HCMs Spherical uniformity Surface finish

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Experimental study on the electrohydrodynamic deformation of droplets in a combined DC electric field and shear flow field: 收藏
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引用; Fundamental Research 2023年第2期3卷 274-287页; 作者： xiangdong liu Guanqiu Hao Bo Li Yongping Chen Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096China School of Electrical Energy and Power EngineeringYangzhou UniversityYangzhou 225009China Laser Fusion Research Center China Academy of Engineering PhysicsMianyang 621900China; A visualization experiment was conducted to investigate the electrohydrodynamic deformation of droplets in a combined DC electric field and shear flow *** experimental data on both the transient and steady droplet def... 详细信息; A visualization experiment was conducted to investigate the electrohydrodynamic deformation of droplets in a combined DC electric field and shear flow *** experimental data on both the transient and steady droplet deformation parameters(D)and orientations(ϕ_(d))are provided at R>S and RS and RS and RS and higher under R; 关键词： Droplet deformation Electrohydrodynamics Electric field Shear flow Prediction model; 来源：维普期刊数据库评论; 学校读者我要写书评

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A New Method Based on Polytopic Linear Inclusion for Nonlinear filter with Non-Gaussian Noise

A New Method Based on Polytopic Linear Inclusion for Nonline...

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第25届中国控制与决策会议

作者： Bing liu Zhen Chen xiangdong liu Fan Yang School of Automation Beijing Institute of Technology Key Laboratory for Intelligent Control & Decision of Complex Systems Beijing Institute of Technology

This paper presents a new method based on the polytopic linear differential inclusion and the robust mixed H2/∞ filtering for the design of the nonlinear filter with non-Gaussian noises. The main goal is to solve the... 详细信息

ISBN: (纸本)9781467355322

This paper presents a new method based on the polytopic linear differential inclusion and the robust mixed H2/∞ filtering for the design of the nonlinear filter with non-Gaussian noises. The main goal is to solve the problems of the complexity and large calculation number in the general nonlinear filter and the filtering design problem for systems with the non-Gaussian noises. The noises considered in the paper involve two different kinds of noises: white noises and energy bounded noises. Differing from the linearization in most nonlinear filters, the estimation error system for the nonlinear system is represented by an uncertain polytopic linear model, based on which, the rectification equations for the predicted errors are designed following the robust mixed H2/∞ filtering. The state estimates for the nonlinear system are given through updating the predictions by the rectified quantities, where, the state predicted quantities of the nonlinear system are gained by the prediction equation of the EKF. The evident advantage of the new filter is the filter coefficients of the rectification equation are constant, without the need to evaluate the Jacobian matrixes. As a result, the calculation number for the new filter is decreased much and the real-time performance of the new filter is much better than the EKF, though the accuracy is a little decline. Its effectiveness is demonstrated by using an example and the statistics result of the calculation number for the filters in the example.

关键词： nonlinear filter polytopic linear inclusion non-Gaussian noise

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Omni-Channel Retailing and Firm Performance from a Customer Lifetime Value Perspective

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China Economist 2024年第3期19卷 89-103页

作者： liu xiangdong Mi Zhuang He Mingqin Business School Renmin University of ChinaBeijing

In the digital era,retailers are keen to find out whether omni-channel retailing helps improve long-term firm *** this paper,we employ machine learning techniques on a large consumption data set in order to measure cu... 详细信息

In the digital era,retailers are keen to find out whether omni-channel retailing helps improve long-term firm *** this paper,we employ machine learning techniques on a large consumption data set in order to measure customer lifetime value(CLV)as the basis for determining long-term firm performance,and we provide an empirical analysis of the relationship between omni-channel retailing and *** results suggest that omni-channel retailing may effectively enhance *** analysis reveals that this process is influenced by heterogeneous consumer requirements and that significant differences exist in the extent to which the omni-channel transition may influence CLV depending on consumer preferences for diversity of commodities,sensitivity to the cost of contract performance,and sensitivity to warehousing ***,retailers should provide consumers with a complete portfolio of goods and services based on target consumers’heterogeneous requirements in order to increase omni-channel efficiency.

关键词： Omni-channel retailing customer lifetime value machine learning heterogeneous consumer requirements

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