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Preparation Process and Mechanical Properties of PLA/PCL Intravascular Stent

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Journal of Donghua University(English Edition) 2014年第5期31卷 640-642页

作者： wang cong-er Key Laboratory of Textile Science & Technology Ministry of Education Donghua University Shanghai 201620 China College of Textiles Donghua University Shanghai 201620 China

A hand-made biodegradable intravascular stent with zig- zag structure has been developed, which made from polylactic acid （ PLA ） braided thread and poly-eaprolactone （ PCL ） tube. This paper showed the preparation process of the PLA braded thread and stent, and discussed the heat setting process of the stents. The sixteen groups of stents were made for the heat setting experiments, discussing two factors on four levels. Radial compression behavior of stents was tested by plate compression method. The result showed that both the heat setting temperature and time had significant effects on stent compression strength. The compression recovery rate was mainly affected by heat setting temperature. The optimized heat setting condition should be 90-100℃ for 45 rain.

关键词： biodegradable intravascular stents polylactic acid(PLA) heat setting process compression properties

Deterministic learning of completely resonant nonlinear wave systems with Dirichlet boundary conditions

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控制理论与应用（英文版） 2012年第2期10卷 201-209页

作者： Tao Peng cong wang College of Automation Science and Engineering South China University of Technology Guangzhou Guangdong 510640 China

In this paper, we investigate the approximation of completely resonant nonlinear wave systems via deter- ministic learning. The plants are distributed parameter systems （DPS） describing homogeneous and isotropic elastic vibrat- ing strings with fixed endpoints. The purpose of the paper is to approximate the infinite-dimensional dynamics, rather than the parameters of the wave systems. To solve the problem, the wave systems are first transformed into finite-dimensional dynamical systems described by ordinary differential equation （ODE）. The properties of the finite-dimensional systems, including the convergence of the solution, as well as the dominance of partial system dynamics according to point-wise measurements, are analyzed. Based on the properties, second, by using the deterministic learning algorithm, an approxi- mately accurate neural network （NN） approximation of the the finite-dimensional system dynamics is achieved in a local region along the recurrent trajectories. Simulation studies are included to demonstrate the effectiveness of the proposed approach.

关键词： Deterministic learning Wave system Completely resonant Finite-dimensional approximation RBF neu-ral networks System dynamics

Probing microstructural evolution in weld metals subjected to varied CaF_(2)-TiO_(2) flux cored wires under high heat input electro-gas welding

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Journal of Iron and Steel Research International 2023年第1期30卷 150-157页

作者： Xu Xie Ming Zhong Tan Zhao cong wang Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819LiaoningChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina State Key Laboratory of Advanced Special Steel Shanghai UniversityShanghai 200444China State Key Laboratory of Metal Material for Marine Equipment and Application Ansteel Co.Ltd.Anshan 114021LiaoningChina

Fused CaF_(2)-TiO_(2) fluxes have been designed,prepared,and applied in the flux cored wires to join EH36 shipbuilding steels under high heat input electro-gas *** microstructural evolution in the weld metals subjected to varied CaF_(2)-TiO_(2) flux cored wires has been fully *** has been demonstrated that as the content of TiO2 in the fused fluxes increases,columnar grain size increases,and major constituents in the weld metal change from lath bainite,to granular bainite,and then to acicular *** phenomena are elucidated via salient chemical reactions involving oxygen pickup and concurrent titanium transfer.

关键词： Microstructural evolution Elemental variation Electro-gas welding High heat input Shipbuilding steel

Effect of Sm doping into CuInTe_(2) on cohesive energy before and after light absorption

维普期刊数据库评论

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维普期刊数据库

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Chinese Physics B 2021年第4期30卷 198-205页

作者： Tai wang Yong-Quan Guo cong wang School of Energy Power and Mechanical Engineering North China Electric Power UniversityBeijing 102206China

The effects of Sm doping into CuInTe_(2) chalcopyrite on the cohesive energy before and after light absorption are systematically investigated by the empirical electron theory(EET) of solids and *** results show that the static energy of CuIn_(1-x)Sm_(x)Te_(2) decreases with Sm content increasing due to the valence electronic structure modulated by doping Sm into CuIn_(1-x)Sm_(x)Te_(2).The calculated optical absorption transition energy from the static state to the excited energy level in CuIn_(1-x)Sm_(x)Te_(2) accords well with the experimental absorption bandgap of CuIn_(1-x)Sm_(x)Te_(2).Moreover,it is found that the energy bandgap of CuIn_(1-x)Sm_(x)Te_(2) is significantly widened with Sm content increasing due to its special valent electron structure,which is favorable for enhancing the light absorption in a wider range and also for the potential applications in solar cells.

关键词： CuIn_(1-x)Sm_(x)Te_(2) empirical electron theory(EET) light absorption bandgap hybridization energy

Autonomous mission reconstruction during the ascending flight of launch vehicles under typical propulsion system failures

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Chinese Journal of Aeronautics 2022年第6期35卷 211-225页

作者： Zhengyu SONG Yin LIU Yong HE cong wang China Academy of Launch Vehicle Technology Beijing 100076China Beijing Institute of Astronautical Systems Engineering Beijing 100076China Beijing Aerospace Automatic Control Institute Beijing 100854China

In recent years, Chinese Long March(LM) launchers have experienced several launch failures, most of which occurred in their propulsion systems, and this paper studies Autonomous Mission Reconstruction(AMRC) technology to alleviate losses due to these failures. The status of the techniques related to AMRC, including trajectory and mission planning, guidance methods,and fault tolerant technologies, are reviewed, and their features are compared, which reflect the challenges faced by AMRC technology. After a brief introduction about the failure modes of engines that can occur during flight, and the fundamentals of trajectory planning and joint optimization of the target orbit and flight path, an AMRC algorithm is proposed for geostationary transfer orbit launch missions. The algorithm evaluates the residual performance onboard, and plans new objectives and corresponding flight path by iterative guidance mode or segmented state triggered optimization methods in real-time. Three failure scenarios that have occurred during previous LM missions are simulated to check the robustness of the algorithm: imminent explosion risk of the boosters’ engines, thrust drop during the first stage of flight, and being unable to start the engine during the second stage. The payloads would fall from space according to the current design under these conditions, but they were saved with the AMRC algorithm in the simulations, which allowed the rocket to get into the target orbit as intended or the payloads were deployed in other orbits without crashing. Although spaceflight can be very unforgiving, the AMRC algorithm has the potential to avoid the total loss of a launch mission when faced with these kinds of typical failures.

关键词： Autonomous mission reconstruction Closed-loop guidance State triggered indices Rescue orbits Launch vehicles

Camouflaged people detection based on a semi-supervised search identification network

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Defence Technology（防务技术） 2023年第3期21卷 176-183页

作者： Yang Liu cong-qing wang Yong-jun Zhou College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing211106China Science and Technology on Near-Surface Detection Laboratory Wuxi214000China

Automated detection of military people based on the images in different environments plays an important role in accurately completing military *** the equipment gradually moving towards intelligence,unmanned aerial vehicles(UAVs)will be widely used for integrated reconnaissance/attack in the *** lightweight and compact design of the small UAV allows it to travel through dense forests and other environments to capture images with its convenient ***,as the camouflage has been designed to blend in with surroundings,which greatly reduces the probability of the target being ***,the lack of training data on camouflaged people detection will inhibit the training of a deep *** address these problems,a novel semi-supervised camouflaged military people detection network is proposed to automatically detect the target from the *** this paper,the camouflaged object detection dataset(COD10K)is first supplemented according to our mission requirements,then the edge attention is utilized to enhance the boundaries based on search identification ***,a semi-supervised learning strategy is presented to take advantage of the unlabeled data which can alleviate insufficient data and improve the detection *** demonstrate that the proposed semi-supervised search identification network(Semi-SINet)performs well in camouflaged people detection compared with other object detection methods.

关键词： network environments utilized

Identification and Learning Control of Strict-Feedback Systems Using Adaptive Neural Dynamic Surface Control

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Identification and Learning Control of Strict-Feedback Syste...

Residual-driven Fuzzy C-Means Clustering for Image Segmentation

第25届中国控制与决策会议

作者： Min wang cong wang College of Automation Science and Engineering South China University of Technology

ISBN: (纸本)9781467355339

This paper focuses on identification and learning from adaptive neural dynamic surface control （DSC） for a class of nth-order strict-feedback systems. In the previous neural learning control proposed using backstepping, intermediate variables are often used as neural network （NN） inputs to keep the dimension of NN inputs minimal. However, the number and complexity of intermediate variables increase as the increasing order of the system. This makes it difficult to achieve learning for the high-order strict-feedback systems due to "the explosion of complexity". To overcome the difficulty, a stable adaptive neural DSC is proposed with auxiliary first-order filters. Due to the use of DSC, the derivative of the filter output variable is used as the NN input instead of the previous intermediate variables. This reduces greatly the dimension of NN inputs, especially for high-order systems. After the stable DSC design, we decompose the stable closed-loop system into a series of linear time-varying （LTV） perturbed subsystems. Using a recursive design, the recurrent property of the NN input variables is easily proven since the complexity is overcome using DSC. Subsequently, the partial persistent excitation （PE） condition of the radial basis function （RBF） NN is satisfied. By combining a state transformation, accurate approximations of the closed-loop system dynamics are recursively achieved in a local region along recurrent orbits. Consequently, a neural learning control method with the learned knowledge is proposed to achieve the closed-loop stability and the better control performance with the faster tracking convergence rate and the smaller tracking error. Simulation studies are performed to demonstrate the effectiveness of the proposed scheme.

关键词： Deterministic learning Dynamic surface control Persistent excitation Strict-feedback systems

来源： cnki会议评论

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cnki会议

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IEEE/CAA Journal of Automatica Sinica 2021年第4期8卷 876-889页

作者： cong wang Witold Pedrycz ZhiWu Li MengChu Zhou Department of Electrical and Computer Engineering University of AlbertaEdmontonAB T6R 2V4Canada School of Electro-Mechanical Engineering Xidian UniversityXi’an 710071China the Faculty of Engineering King Abdulaziz UniversityJeddah 21589Saudi Arabia School of Electro-Mechanical Engineering Xidian UniversityXi’an 710071and also with the Institute of Systems EngineeringMacao University of Science and TechnologyMacaoChina Institute of Systems Engineering Macao University of Science and TechnologyMacao 999078China the Helen and John C.Hartmann Department of Electrical and Computer Engineering New Jersey Institute of TechnologyNewarkNJ 07102 USA

In this paper,we elaborate on residual-driven Fuzzy C-Means(FCM)for image segmentation,which is the first approach that realizes accurate residual(noise/outliers)estimation and enables noise-free image to participate in *** propose a residual-driven FCM framework by integrating into FCM a residual-related regularization term derived from the distribution characteristic of different types of *** on this framework,a weighted?2-norm regularization term is presented by weighting mixed noise distribution,thus resulting in a universal residual-driven FCM algorithm in presence of mixed or unknown ***,with the constraint of spatial information,the residual estimation becomes more reliable than that only considering an observed image *** experiments on synthetic,medical,and real-world images are *** results demonstrate the superior effectiveness and efficiency of the proposed algorithm over its peers.

关键词： Fuzzy C-Means image segmentation mixed or unknown noise residual-driven weighted regularization

Profiling interfacial reaction features between diamond and Cu-Sn-Ti active filler metal brazed at 1223 K

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Journal of Materials Science & Technology 2022年第36期131卷 100-105页

作者： Yonggang Fan Kenan Li Haodong Li cong wang Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) School of MetallurgyNortheastern UniversityShenyang 110819China State Key Laboratory of Superabrasives Zhengzhou Research Institute for Abrasives&Grinding Co.Ltd.Zhengzhou 450001China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Diamond/Cu-Sn-Ti composites have been successfully prepared by cold-press forming in conjunction with high-temperature vacuum active brazing at 1223 *** wetting behaviors between diamond and filler metal,interfacial characteristics of the reaction layer,and wear resistance of the bulky composite have been fully *** is revealed that all diamond particles can only be fully coated when the TiH_(2)content exceeds 5 wt%,below which sharp edges on diamond can still be *** interfacial reaction layer is found to be composed of TiC,the thickness of which is demonstrated to increase as a function of TiH_(2)content,arriving at the peak value of 1.70μm and remaining almost constant *** is further shown that the maximum wear resistance occurs approaching 5 wt%TiH_(2)*** mechanisms responsible for such interesting phenomena have been postulated.

关键词： Diamond Cu-Sn-Ti Brazing Interfacial layer Powder metallurgy