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Robust Adaptive Model Tracking for Distributed Parameter Control of Linear Infinite-dimensional Systems in Hilbert space

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IEEE/CAA Journal of Automatica Sinica 2014年第3期1卷 294-301页

作者： Mark J.Balas Susan A.Frost the Embry-Riddle aeronautical University the NASA Ames Research Center

This paper is focused on adaptively controlling a linear infinite-dimensional system to track a finite-dimensional reference *** a linear continuous-time infinite-dimensional plant on a Hilbert space with disturbances of known waveform but unknown amplitude and phase,we show that there exists a stabilizing direct model reference adaptive control law with the properties of certain disturbance rejection and *** plant is described by a closed,densely defined linear operator that generates a continuous semigroup of bounded operators on the Hilbert space of *** central result will show that all errors will converge to a prescribed neighborhood of zero in an infinitedimensional Hilbert *** result will not require the use of the standard Barbalat’s lemma which requires certain signals to be uniformly *** result is used to determine conditions under which a linear infinite-dimensional system can be directly adaptively controlled to follow a reference *** particular,we examine conditions for a set of ideal trajectories to exist for the tracking *** results are applied to adaptive control of general linear diffusion systems described by self-adjoint operators with compact resolvent.

关键词： Robustness Adaptation models Adaptive control Hilbert space Trajectory Learning (artificial intelligence)

Improving Joint Features and Mechanical Properties of Pinless Fiction Stir Welding of Alcald 2A12-T4 Aluminum Alloy

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Journal of Materials Science & Technology 2016年第12期32卷 1372-1377页

作者： Zhenlei Liu Hutao Cui Shude Ji Minqiang Xu Xiangchen Meng Harbin institute of Technology Deep Space Exploration Research Center Faculty of Aerospace Engineering Shenyang Aerospace University

As a new solid state welding,pinless friction stir welding（PFSW） can be used to join thin-wall *** this study,four new pinless tools with different groove distributions were designed and manufactured in order to enrich technological storage of PFSW and obtain sound joint with high quality of alclad 2A12-T4 *** results show that the small-obliquity tool is detrimental to the transfer of plasticized materials,resulting in the formation of kissing bond *** the through-groove tool or the large-curvature tool,bigger flashes form on the joint surface and alclad layer is observed in the nugget zone（NZ）,deteriorating mechanical *** with the above-mentioned three tools,using the six-groove tool with rational curvature and obliquity can not only yield sound joint with small flashes and thickness reduction,but also prevent alclad from flowing into NZ,which has potential to weld thin alclad aluminum ***,the tensile strength and elongation of joint using the six-groove tool reach the maximum values of 362 MPa and 8.3%,up to 85.1% and 64% of BM.

关键词： Pinless friction stir welding Groove distribution 2A12-T4 aluminum alloy Macrostructures Mechanical property

Effect of residual-stress on microyield behavior of Al alloy reinforced by SiC_p

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中国有色金属学会会刊：英文版 2005年第S3期15卷 7-11页

作者：李多生左敦稳周贤良华小珍陈同彩张建云 College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016ChinaCollege of Material Science and Engineering Nanchang Institute of Aeronautical Technology Nanchang 330034 China College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016China College of Material Science and Engineering Nanchang Institute of Aeronautical Technology Nanchang 330034 China

Because of the difference in the coefficient of thermal expansion of Al alloy and SiC_p, the residual-stress generates during the process of fabricating Al alloy reinforced by SiC_p. The analyzing residual-stress quantitatively by XRD shows that residual-stress is essential character of Al alloy reinforced by SiC_p, and the residual-stress in Al alloy matrix is tensile stress. The residual-stress decreases along with lessening of SiC_p size, which shows better microyield behavior. In annealing, the residual-stress of LY12+150#SiC_p is lower than that of ZL101+150#SiC, thus it has better microyield behavior. The residual-stress of solution-aging is bigger than that of annealing. The microyield behavior is also explained from the parameter change of microstructure to microyield behavior. space-group relative microdistortion of Al alloy reinforced decreases along with lessening of SiC_p size, which has good microyield behavior.

关键词： microyield SiC_p space-group relative microdistortion XRD residual-stress

Constant modulus semi-blind space-time equalizer based on structure risk minimum criterion

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Journal of Beijing institute of Technology 2013年第4期22卷 536-543页

作者：毛忠阳王红星宋恒李军 Department of Electronic Information Engineering Naval Aeronautical and Astronautical University

A new adaptive filtering principle based on capability control and semi-blind method is presented. A new semi-blind space-time equalizer based on constant modulus characteristic and structure risk minimum （SRM） criterion is also proposed. The equalizer sufficiently exploits the learning information of communication signals by using the structure information of filter itself through capability control technique. Namely, it maximizes the amount of learning information to im- prove filter tracking performance. Simulations are carried out and the result is compared with that of typical recursive least squares space-time equalizer （RLS-STE） and constant modulus semi-blind space-time equalizer （ CM-SB-STE ）. The results show that, even if with insufficient training data, the SRM constant modulus semi-blind space-time equalizer （SCM-SB-STE） keeps good tracking per- formance, showing promises in mobile wireless communications.

关键词： equalization space-time filter capability control semi-blind constant modulus

Numerical Study of φ^4 Model by Potential Importance Sampling Method

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Communications in Theoretical Physics 2006年第5期45卷 873-876页

我们调查自发的对称为 4 由使用潜在的重要性采样方法在参数空格在一个方形的格子上建模的φ ~ 碎的现象，它被 Milchev， Heermann，和文件夹建议[J。Stat。Phys。44 (1986 ) 749 ] 。参数的批评价值允许我们决定模型的阶段图。同时，... 详细信息

我们调查自发的对称为 4 由使用潜在的重要性采样方法在参数空格在一个方形的格子上建模的φ ~ 碎的现象，它被 Milchev， Heermann，和文件夹建议[J。Stat。Phys。44 (1986 ) 749 ] 。参数的批评价值允许我们决定模型的阶段图。同时，象危险性那样的一些相关数量和特定的热也被获得。

关键词：对称性阻断潜在重要性抽样法 φ4模型参量空间

A New Three-dimensional Cd Metal-organic Framework Based on a C-centered Tripodal Flexible Carboxylate and 1,2-Bis(4-pyridyl)ethane Mixed Ligands

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Chinese Journal of Structural Chemistry 2015年第12期34卷 1915-1921页

作者：崔节虎杜秀红 College of Civil Engineering and Architecture Zhengzhou Institute of Aeronautical Industry Management State Key Laboratory of Coordination Chemistry Nanjing University Clinical Laboratory Medicine Henan Medical College

A new MOF {[Cd3（TCOPM）2bpe]·7（H2O）·2DMF}n based on a C-centered tripodal flexible carboxylate ligand and 1,2-bis（4-pyridyl）ethane ligand （HaTCOPM = tris（p-carboxy- phenyl）methane, bpe = 1,2-bis（4-pyridyl） ethane） has been synthesized by the hydrothermal reaction in mixed DMF/H2O solution under 95 ℃. The structure has been determined by single-crystal X-ray diffraction analysis and elemental analysis, IR spectroscopy, and thermogravimetric analysis. Crystal data for the title complex are as follows： triclinic system, space group P/with a = 9.2637（14）, b = 13.273（2）, c = 14.160（2） A, a = 9.2637（14）, β = 13.273（2）, γ, = 105.585（2）°, V= 1487.6（4） A3, Mr= 1268.11, Z = 1, F（000） = 628, Dc = 1.416 g/cm3,μ（MoKa） = 1.110 mm^-1, R = 0.0482 and wR = 0.1444 for 5207 observed reflections with I 〉 2σ（I）. MOF 1 consists of an infinite 3D network using TCOPM^3- and bpe as mixed bridge ligands. Fluorescence spectrum measurement indicates that MOF 1 shows strong fluorescence emission at 437 nm （λmax） in the solid state at room temperature and realizes tunable emission spectrum through tuning from single to mixed ligand.

关键词： TCOPM bpe fluorescence MOF

Newly established autonomous adaptive low-power instrument platform(AAL-PIP) chain on East Antarctic Plateau and operation

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Advances in Polar Science 2019年第4期30卷 362-374页

作者： Zhonghua XU Michael DHARTINGER Robert CLAUER Daniel WEIMER Kshitija DESHPANDE Hyomin KIM Stephen MUSKO Anna WILLER Thomas EDWARDS Shane COYLE Yuxiang PENG Dong LIN John BOWMAN Bradley Department of Electrical and Computer Engineering Virginia TechBlacksburgVA 24061USA Center for space Plasma Physics Space Science InstituteBoulderCO 80301USA Department of Physical Sciences Embry-Riddle Aeronautical UniversityDaytona BeachFL 32114USA Center for Solar-Terrestrial Research New Jersey Institute of TechnologyNewarkNJ 07102USA space Physics Research Laboratory College of EngineeringUniversity of MichiganAnn ArborMI48109USA DTU space National Space InstituteTechnical University of DenmarkKongens LyngbyDenmark

An autonomous adaptive low-power instrument platform(AAL-PIP)chain of six stations has been newly established on East Antarctic Plateau along the 40°geomagnetic meridian,to investigate interhemispheric geomagnetically conjugate current systems,waves,and other space weather phenomena in Polar *** six stations,PG0 to PG5,which host low-power magnetometers(Fluxgate and Searchcoil),dual frequency GPS receivers,HF radio experiment,and run autonomously with solar power and two-way satellite communication,are designated at the geomagnetically conjugate(based on the International Geomagnetic Reference Field)locations of the West Greenland geomagnetic chain covering magnetic latitudes from 70°to 80°.We present the development,deployment,and operation of this chain,as well as the data collected by the chain and some preliminary scientific results showing evidence of interhemispheric asymmetries,which are important to better understand Solar Wind–Magnetosphere–Ionosphere(SWMI)coupling in Polar *** investigations focus on magnetic impulse(MI)events,traveling convection vortices(TCVs),and ultra-low frequency(ULF)waves in the coupled southern and northern hemispheres.

关键词： magnetometers magnetic perturbation magnetic conjugate

Science Missions Using CubeSats

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空间科学学报 2020年第4期40卷 443-461页

作者： SEYEDABADI M E FALANGA M AZAM M BARESI N FLÉRON R JANTARACHOTE V JUAREZ ORTIZ V A JULCA YAYA J J LANGER M MANUTHASNA S MARTINOD N MUGHAL M R NOMAN M PARK J PIMNOO A PRAKS J REYNERI L SANNA A ŞIŞMAN TÇ SOME J ULAMBAYAR T YU Xiaozhou DONG Xiaolong BALDIS L Asia-Pacific space Cooperation Organization 100070 BeijingChina International space Science institute-Beijing 100190 BeijingChina International space Science institute 3012 BernSwitzerland Bangladesh space Research and Remote Sensing Organization 1207 DhakaBangladesh Japan Aerospace Exploration Agency Institute of Space Astronautical Science252-5210 TokyoJapan Technical University of Denmark 2800 LyngbyDenmark Department of Electrical Engineering Faculty of EngineeringPrince of Songkla University90112 SongkhlaThailand National Commission of Aerospace Research and Development 15046 San IsidroPeru Technical University of Munich 80333 MunichGermany Mahanakorn University of Technology 10530 BangkokThailand Swiss Federal institute of Technology Lausanne 1015 LausanneSwitzerland institute of space Technology 44000 IslamabadPakistan Korea Astronomy and space Science institute 34055 DaejeonSouth Korea Geo-Informatics and space Technology Development Agency 10210 BangkokThailand Department of Electronics and Nanoengineering Aalto University02150 EspooFinland Department of Electronics and Telecommunications Polytechnic of Turin10129 TurinItaly Department of Physics University of Cagliari09042 MonserratoItaly Department of Astronautical Engineering University of Turkish Aeronautical Association06790 AnkaraTurkey Nanosatellite Development Laboratory National University of Mongolia210646 UlaanbaatarMongolia Dalian University of Technology 116024 DalianChina National space Science Center 100190 BeijingChina

As the role of missions and experiments carried out in outer space becomes more and more essential in our understanding of many earthly problems,such as resource management,environmental problems,and disaster management,as well as space science questions,thanks to their lower cost and faster development process CubeSats can benefit humanity and therefore,young scientists and engineers have been motivated to research and develop new CubeSat *** very long after their inception,CubeSats have evolved to become accepted platforms for scientific and commercial *** last couple of years showed that they are a feasible tool for conducting scientific experiments,not only in the Earth orbit but also in the interplanetary *** many countries,a CubeSat mission could prompt the community and young teams around the world to build the national capacity to launch and operate national space *** paper presents an overview of the key scientific and engineering gateways opened up to the younger scientific community by the advent and adaptation of new technology into CubeSat *** role of cooperation and the opportunities for capacity-building and education are also ***,the present article also aims to provide useful recommendations to scientists,early-career researchers,engineers,students,and anyone who intends to explore the potential and opportunities offered by CubeSats and CubeSats-based missions.

关键词： CubeSat space science Small satellites for space science Education Earth observation

Survey and technological analysis of laser and its defense applications

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Defence Technology（防务技术） 2021年第2期17卷 583-592页

作者： Syed Affan Ahmed Mujahid Mohsin Syed Muhammad Zubair Ali Department of Avionics Engineering-College of aeronautical Engineering(CAE) National University of Sciences and Technology(NUST)RisalpurKPKPakistan

The laser technology has made remarkable progress over the past couple of *** is being widely employed in diverse domains,such as holography,space sciences,spectroscopy,medical sciences,micro and power electronics,industrial engineering,and most distinctively,as directed energy military *** to their active transmissions,laser systems are similar to microwave radars to some extent;however,unlike conventional radars,the laser operates at very high frequencies thus making it a potent enabler of narrow-beam and high energy aerial deployments,both in offensive and defensive *** modern avionics systems,laser target indicators and beam riders are the most common devices that are used to direct the Laser Guided Weapons(LGW)accurately to the ground ***,compact size and outstanding angular resolution of laser-based systems motivate their use for drones and unmanned aerial ***,the narrow-beam divergence of laser emissions offers a low probability of intercept,making it a suitable contender for secure transmissions and safety-critical ***,the developments in space sciences and laser technology have given synergistic potential outcomes to use laser systems in space *** paper comprehensively reviews laser applications and projects for strategic defense actions on the ground or in ***,a detailed analysis has been done on recent advancements of the laser technology for target indicators and *** also reviews the advancements in the field of laser communications for surveillance,its earlier state of the art,and ongoing scientific research and advancements in the domain of high energy directed laser weapons that have revolutionized the evolving military *** offering a comprehensive taxonomy,the paper also critically analyzes some of the recent contributions in the associated domains.

关键词： Laser systems Laser military applications Directed energy weapons Non-lethal weapons Laser military projects Survey Taxonomy