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An Integrated Approach to Hypersonic Entry Attitude Control

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International Journal of Automation and computing 2014年第1期11卷 39-50页

作者： Zhi-Qiang Pu Ru-Yi Yuan Xiang-min tan Jian-Qiang Yi Institute of Automation Chinese Academy of Sciences

This paper presents an integrated approach based on dynamic inversion(DI)and active disturbance rejection control(ADRC)to the entry attitude control of a generic hypersonic vehicle(GHV).DI is frstly used to cancel the nonlinearities of the GHV entry model to construct a basic attitude *** enhance the control performance and system robustness to inevitable disturbances,ADRC techniques,including the arranged transient process(ATP),nonlinear feedback(NF),and most importantly the extended state observer(ESO),are integrated with the basic DI *** one primary task,the stability and estimation error of the second-order nonlinear ESO are analyzed from a brand new perspective:the nonlinear ESO is treated as a specifc form of forced Li′enard *** qualitative properties of the Li′enard system are utilized to yield comprehensive theorems on nonlinear ESO solution behaviors,such as the boundedness,convergence,and existence of periodic *** portraits of ESO estimation error dynamics are given to validate our *** last,three groups of simulations,including comparative simulations with modeling errors,Monte Carlo runs with parametric uncertainties,and a six degrees-of-freedom reference entry trajectory tracking are executed,which demonstrate the superiority of the proposed integrated controller over the basic DI controller.

关键词： Hypersonic vehicle attitude control dynamic inversion active disturbance rejection control stability analysis

A New Calibration Method for an Inertial and Visual Sensing System

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International Journal of Automation and computing 2012年第3期9卷 299-305页

作者： Xu, De Wang, Hua-Wei Li, You-Fu tan, min State Key Laboratory of Intelligent Control and Management of Complex Systems Institute of Automation Chinese Academy of Sciences Beijing 100190 China East China Research Institute of Electronic Engineering Hefei 230088 China Department of Manufacturing Engineering and Engineering Management City University of Hong Kong Hong Kong China

The relative pose between inertial and visual sensors equipped in autonomous robots is calibrated in two steps. In the first step, the sensing system is moved along a line, the orientations in the relative pose are computed from at least five corresponding points in the two images captured before and after the movement. In the second step, the translation parameters in the relative pose are obtained with at least two corresponding points in the two images captured before and after one step motion. Experiments are conducted to verify the effectiveness of the proposed method.

关键词： Inertial sensor visual sensor calibration motion estimation robot vision.

Synthesis and Properties of New Infrared Nonlinear Optical Li_2Ga_2GeS_6 Crystal

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Journal of Wuhan University of Technology(Materials Science) 2015年第3期30卷 509-511页

作者：宋满刘启明 tan min CHEN Ruiqi YANG Sanjun School of Physics and Technology Key Lab of Artifi cial Micro-and Nano-structures of Ministry of Education Wuhan University

IR Li2Ga2GeS6 nonlinear crystals were directly obtained with the composition of 40GeS2- 30Ga2Ss-30LieS, by the conventional melt-quenching method. The high depth digital image indicated that the obtained LizGa2GeS6 crystals showed a big size of 0.3 × 0.25 × 0.3 mm3. It was shown that the compound was very suscepfive to H20 with second harmonic observation. Besides, the glass-forming region of GeS2-Ga2S3- Li2S system was further studied by the conventional melt-quenching ***2-Ga2S3-Li2S glass-ceramics containing IR Li2Ga2GeS6 nonlinear nanocrystals were obtained at a more carefully controlled heating rate.

关键词： IR Li2Ga2GeS6 nonlinear crystals glass-forming region size

Necessary and Sufficient Conditions for Solving Leader-Following Problem of Multi-Agent Systems with Communication Noises

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Necessary and Sufficient Conditions for Solving Leader-Follo...

Synthesis and Crystal Structure of 1,4-Dimethyl-2,5-di{[2’-(3-pyridylmethylamino-formyl)phenoxyl]methyl}benzene Perchlorate

第25届中国控制与决策会议

作者： Yunpeng Wang Long Cheng Zeng-Guang Hou min tan Huiyang Liu min Wang State Key Laboratory of Management and Control for Complex Systems (SKLMCCS) Institute of Automation Chinese Academy of Sciences School of Information and Electrical Engineering Shandong Jianzhu University

ISBN: (纸本)9781467355339

The leader-following problem of first-order integral multi-agent systems with communication noises is investigated in this paper. To attenuate the noise’s effect, a positive time-varying gain a（t） is employed in the protocol. It is proved that the proposed protocol can solve the mean square leader-following problem if the following conditions hold: 1) the communication topology graph has a spanning tree;2) ∫∞0 a（t）dt = ∞;3) lim t→∞ a（t） = 0. The requirements on a（t） are different from most existing papers, where a（t） is required to satisfy that ∫∞0 a（t） = ∞ and ∫∞0 a2（t）＜ ∞. It turns out that ∫∞0 a2（t）＜ ∞ implies lim t→∞ a（t） = 0, if a（t） is uniformly continuous. Therefore this paper relaxes the requirements on a（t） to some extent. In addition, under the mild condition （a（t） is uniformly continuous） these three conditions are necessary as well. Furthermore, if ∫∞0 a2（t）＜∞, the employed protocol is proved to be able to solve the almost sure leader-following problem of first-order integral multi-agent system. Finally, a simulation example is provided to verify the effectiveness of the employed protocols.

关键词： Leader-following Consensus Multi-agent system Communication noise

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Chinese Journal of Structural Chemistry 2008年第4期27卷 451-454页

作者： tanG Kuan-Zhen tanG Yu LI Ya-Fei LIU Wei-Sheng tan min-Yu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University

The title compound, 1,4-dimethyl-2,5-di { [2′-（3-pyridylmethylaminoformyl）phenoxyl]- methyl}benzene perchlorate （C36H36Cl2N4O12, Mr = 787.59）, has been synthesized and structurally determined by single-crystal X-ray diffraction. The crystal crystallizes in the orthorhombic system, space group Pbca with a = 14.366（4）, b = 15.159（4）, c = 16.443（5）A, V = 3580.9（17）/A3 Z = 4, De = 1.461 g/cm^3, /t = 0.253 mm^-1, F（000） = 1640, R = 0.0618 and wR = 0.1525 for 1615 observed reflections （I 〉 2σ（I））. In the structure of the title compound, a two-dimensional supramolecular layer is formed via intermolecular hydrogen bonding interactions.

关键词： 2,5-dimethyl-l,4-di{ [2′-(3-pyridylmethylaminoformyl)phenoxyl]methyl)benzene,synthesis spectral characterization crystal structure

Two cases of small bowel obstruction due to a shiitake mushroom

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Gastroenterology Report 2019年第4期7卷 298-300,I0002页

作者： Jinfu tan Kaitao Yuan Jidong Zuo Weigang Dai Yujie Yuan Weidong Feng min tan Jinping Ma Unit 3 Center for Gastrointestinal SurgeryThe First Affiliated Hospital of Sun Yat-Sen University

The shiitake mushroom(Lentinula edodes),known as Xiang-gu in China,has been an important component of Asian cuisine for hundreds of *** not easily digestible,there are few reports of them causing bowel *** present two cases of small bowel obstruction due to a shiitake mushroomrequiring surgical *** patients who did not have any teeth and did not use dentures presented with intestinal bowel obstruction and were referred to the Emergency Department of our hospital after eating a meal including shiitake mushrooms without *** first patient underwent an emergency laparotomy and a semental small bowel resection and the other underwent laparoscopic small bowel incision for removal of a foreign *** causes of the small bowel obstruction for the two patients were uncut shiitake mushrooms in the small *** two patients recovered uneventfully post-operatively.

关键词： Shiitake mushroom small bowel obstruction

Development of Ce-based sintered magnets: review and prospect

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Journal of Iron and Steel Research International 2020年第1期27卷 1-11页

作者： An-hua Li Long-long Xi Hai-bo Feng Ning Zou min tan ming-gang Zhu Wei Li Division of Functional Material Central Iron&Steel Research InstituteBeijing 100081China Ningbo Funeng New Material Company Ningbo 315336ZhejiangChina

Ce-based magnets have attracted extensive attention in both academia and industry due to their excellent property-price ratio and distinctive phase ***,Ce-based sintered magnets have widely tunable magnetic properties with changing Ce ***,they can be used to meet many different application requirements from packaging market to driving motors,*** intrinsic magnetic properties,phase composition,and microstructures of the Ce-based sintered magnets with different Ce contents have been *** service performances such as temperature stability,corrosion resistance,mechanical properties and thermal expansion of commercial Ce-based sintered magnets are *** research and development trends of the Ce-based magnets in the future are pointed out.

关键词： Ce-based sintered magnet Ce content Phase structure Magnetic property Service performance

Evaluation of a Regional Ensemble Data Assimilation System for Typhoon Prediction

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Advances in Atmospheric Sciences 2022年第11期39卷 1816-1832页

作者： Lili LEI Yangjinxi GE Zhe-min tan Yi ZHANG Kekuan CHU Xin QIU Qifeng QIAN Key Laboratory of Mesoscale Severe Weather/ministry of Education School of Atmospheric SciencesNanjing UniversityNanjing 210063China National Meteorological Center China Meteorological AdministrationBeijing 100081China

An ensemble Kalman filter(EnKF) combined with the Advanced Research Weather Research and Forecasting model(WRF) is cycled and evaluated for western North Pacific(WNP) typhoons of year 2016. Conventional in situ data, radiance observations, and tropical cyclone(TC) minimum sea level pressure(SLP) are assimilated every 6 h using an 80-member ensemble. For all TC categories, the 6-h ensemble priors from the WRF/EnKF system have an appropriate amount of variance for TC tracks but have insufficient variance for TC intensity. The 6-h ensemble priors from the WRF/EnKF system tend to overestimate the intensity for weak storms but underestimate the intensity for strong storms. The 5-d deterministic forecasts launched from the ensemble mean analyses of WRF/EnKF are compared to the NCEP and ECMWF operational control forecasts. Results show that the WRF/EnKF forecasts generally have larger track errors than the NCEP and ECMWF forecasts for all TC categories because the regional simulation cannot represent the large-scale environment better than the global simulation. The WRF/EnKF forecasts produce smaller intensity errors and biases than the NCEP and ECMWF forecasts for typhoons, but the opposite is true for tropical storms and severe tropical storms. The 5-d ensemble forecasts from the WRF/EnKF system for seven typhoon cases show appropriate variance for TC track and intensity with short forecast lead times but have insufficient spread with long forecast lead times. The WRF/EnKF system provides better ensemble forecasts and higher predictability for TC intensity than the NCEP and ECMWF ensemble forecasts.

关键词： ensemble Kalman filter typhoon prediction ensemble forecast

Solar Flare Forecast Model Based on Resampling and Fusion Method

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Research in Astronomy and Astrophysics 2022年第8期22卷 238-248页

作者： Jie Wan Jun-Feng Fu Dai-min tan Ke Han Meng-Yao Yu Peng E Laboratory for Space Environment and Physical Sciences Harbin Institute of TechnologyHarbin 150001China School of Electrical Engineering and Automation Harbin Institute of TechnologyHarbin 150001China School of Computer and Information Engineering Harbin University of CommerceHarbin 150028China

Predicting the activity of solar flares is of great significance for studying its physical mechanism and the impact on human production and *** such as class imbalance,high time-series sensitivity,and over-localization of important features exist in the sample data used for flare *** design a solar flare fusion method based on resampling and the CNN-GRU algorithm to try to solve the above *** order to verify the effectiveness of this fusion method,first,we compared the forecast performance of different resampling methods by keeping the forecast model ***,we used the resampling algorithm with high performance to combine some single forecast models and fusion forecast models *** use the 2010-2017 sunspot data set to train and test the performance of the flare model in predicting flare events in the next 48 *** the conclusion of the above steps,we prove that the resampling method SMOTE and its variant SMOTE-ENN are more advantageous in class imbalance problem of flare *** addition,after the fusion of one-dimensional convolution and recurrent network with"forget-gate",combined with the SMOTE-ENN to achieve TSS=61%,HSS=61%,TP_(Rate)=77%and TN_(Rate)=83%.This proves that the fusion model based on resampling and the CNN-GRU algorithm is more suitable for solar flare forecasting.

关键词： (Sun:)sunspots Sun:flares Sun:X-rays gamma-rays Sun:magnetic fields Sun:corona