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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1485-1498页

作者： you zhao xing He Mingliang Zhou Tingwen Huang Chongqing Key Laboratory of Nonlinear Circuits and Intelligent Information Processing College of Electronic and Information EngineeringSouthwest UniversityChongqing 400715China School of Computer Science Chongqing UniversityChongqing 400044China Department of Mathematics Texas A&M University at QatarDoha 23874Qatar IEEE

The Nesterov accelerated dynamical approach serves as an essential tool for addressing convex optimization problems with accelerated convergence *** previous studies in this field have primarily concentrated on unconstrained smooth con-vex optimization *** this paper,on the basis of primal-dual dynamical approach,Nesterov accelerated dynamical approach,projection operator and directional gradient,we present two accelerated primal-dual projection neurodynamic approaches with time scaling to address convex optimization problems with smooth and nonsmooth objective functions subject to linear and set constraints,which consist of a second-order ODE(ordinary differential equation)or differential conclusion system for the primal variables and a first-order ODE for the dual *** satisfying specific conditions for time scaling,we demonstrate that the proposed approaches have a faster conver-gence *** only requires assuming convexity of the objective *** validate the effectiveness of our proposed two accel-erated primal-dual projection neurodynamic approaches through numerical experiments.

关键词： Accelerated projection neurodynamic approach lin-ear and set constraints projection operators smooth and nonsmooth convex optimization time scaling.

New Xanthones from Polygala crotalarioides

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Chemical Research in Chinese Universities 2006年第3期22卷 400-402页

作者： DENG Shi-ming YANG Xian-hui zhao you-xing ZHOU Jun State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 P. R. China Ocean College Hainan University Haikou 570228 P. R. China

Introduction Xanthones are secondary metabolites commonly occurring in a few higher plant families, fungi and lichen. Their high taxonomic value in such families and their pharmacological properties, including in vitro cytotoxicity, in vivo antitumour activity, antifungal, antibacterial, antiinflammatory properties and aldose reductase inhibitory activity have provoked great interest. The discovery of the antidiabetic activity of some axnthones＇ from Swertiaceae has prompted us to undertake a more broadly search for novel xanthones from plants of Polygalaceae. The phytochemical investigation has not been performed on this plant up to now. Herein we report the isolation and structure elucidation of two new xanthones （ compounds 1 and 2 ） and three known xanthones （compound 3, 4 and 5 ）.

关键词： Polygala crotalarfoides Polygalaceae Xanthones

A New Phenylpropanoid Glycoside from Dragon＇s Blood of Dracaena cambodiana

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Chemical Research in Chinese Universities 2013年第3期29卷 483-486页

作者： SHEN Hai-yan WANG Hui ZUO Wen-jian zhao you-xing LUO Ying MEI Wen-li DAI Hao-fu Key Laboratory of Biology and Genetic Resources of Tropical Crops Ministry of Agriculture Institute of Tropical Bioscience and Biotechnology Chinese Academy of Tropical Agricultural Sciences Haikou 571101 P R. China Hainan Key Laboratory for Research and Development of Natural Products from Li Folk Medicine Haikou 571101 P. R. China Horticultural and Garden College Hainan University Haikou 570228 P. R. China

A new phenylpropanoid glycoside, named cambodianin F（1）, together with three known compounds, 1-O-β-D-glucopyranosyl-2-hydroxy-4-allylbenzene（ 2 ）, 1-O-（ 6-O-a-L-rhamnopyranosyl-β-D-glucopyranosyl）-2-hydroxy- 4-allylbenzene（3） and 1,2-di-O-β-D-glucopyranosyl-4-allylbenzene（4） was isolated from the dragon＇s blood of Dracaena cambodiana. The new compound was elucidated by HR-ESI-MS and spectroscopic techniques（UV, IR, 1D and 2D NMR）.

关键词： Dragon's blood Dracaena cambodiana Cambodianin F

Analysis of main factors in partial mining subsidence

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中国有色金属学会会刊：英文版 2005年第S1期15卷 73-75页

作者： ZHANG Hua-xing, WANG Jian-xue, zhao you-xing (China Coal Research Institute, Beijing 100013, China)

The partial mining subsidence is a technical method widely used in the mining under buildings. How to calculate the subsidence caused by the partial mining is the key to use this method. By using the numerical calculation method, the main factors affecting the subsidence caused by the partial mining were analyzed, which include the recovery ratio of the partial mining, the width of the mined strip, the thickness and the depth of the mined seam, the conditions of the overburden. The relationship between the partial mining subsidence and the main factors was given according to the calculated results, which provides a theory basis for design and application of the partial mining.

关键词： partial mining main factor subsidence numerical calculation

Dynamic plugging regulating strategy of pipeline robot based on reinforcement learning

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Petroleum Science 2024年第1期21卷 597-608页

作者： xing-Yuan Miao Hong zhao College of Mechanical and Transportation Engineering China University of PetroleumBeijing102249China

Pipeline isolation plugging robot (PIPR) is an important tool in pipeline maintenance operation. During the plugging process, the violent vibration will occur by the flow field, which can cause serious damage to the pipeline and PIPR. In this paper, we propose a dynamic regulating strategy to reduce the plugging-induced vibration by regulating the spoiler angle and plugging velocity. Firstly, the dynamic plugging simulation and experiment are performed to study the flow field changes during dynamic plugging. And the pressure difference is proposed to evaluate the degree of flow field vibration. Secondly, the mathematical models of pressure difference with plugging states and spoiler angles are established based on the extreme learning machine (ELM) optimized by improved sparrow search algorithm (ISSA). Finally, a modified Q-learning algorithm based on simulated annealing is applied to determine the optimal strategy for the spoiler angle and plugging velocity in real time. The results show that the proposed method can reduce the plugging-induced vibration by 19.9% and 32.7% on average, compared with single-regulating methods. This study can effectively ensure the stability of the plugging process.

关键词： Pipeline isolation plugging robot Plugging-induced vibration Dynamic regulating strategy Extreme learning machine Improved sparrow search algorithm Modified Q-learning algorithm

A semantic vector map-based approach for aircraft positioning in GNSS/GPS denied large-scale environment

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Defence Technology（防务技术） 2024年第4期34卷 1-10页

作者： Chenguang Ouyang Suxing Hu Fengqi Long Shuai Shi Zhichao Yu Kaichun zhao Zheng you Junyin Pi Bowen xing State Key Laboratory of Precision Measurement Technology and Instruments Tsinghua UniversityBeijing 100084China School of Mechanical and Information Engineering China University of Mining and Technology(Beijing)Beijing 100083China

Accurate positioning is one of the essential requirements for numerous applications of remote sensing data,especially in the event of a noisy or unreliable satellite *** this end,we present a novel framework for aircraft geo-localization in a large range that only requires a downward-facing monocular camera,an altimeter,a compass,and an open-source Vector Map(VMAP).The algorithm combines the matching and particle filter *** vector and correlation between two building contour vectors are defined,and a coarse-to-fine building vector matching(CFBVM)method is proposed in the matching stage,for which the original matching results are described by the Gaussian mixture model(GMM).Subsequently,an improved resampling strategy is designed to reduce computing expenses with a huge number of initial particles,and a credibility indicator is designed to avoid location mistakes in the particle filter *** experimental evaluation of the approach based on flight data is *** a flight at a height of 0.2 km over a flight distance of 2 km,the aircraft is geo-localized in a reference map of 11,025 km~2using 0.09 km~2aerial images without any prior *** absolute localization error is less than 10 m.

关键词： Large-scale positioning Building vector matching Improved particle filter GPS-Denied Vector map

Design and synthesis of thiol-terminated imidothioether oligomer as thermally latent hardener and modifier for high-performance epoxy/thiol thermosets

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Science China Chemistry 2024年第2期67卷 632-641页

作者： xing Liu Jianjun Zhou Shumei Liu Jianqing zhao School of Materials Science and Engineering South China University of TechnologyGuangzhou510640China Key Lab Guangdong High Property&Functional Polymer Materials Key Laboratory of Polymer Processing EngineeringMinistry of EducationGuangzhou510640China

Conventional base-catalyzed epoxy/aliphatic thiol systems have a poor storage stability,and are impossible to be one-pot systems.A widely accepted solution is to use the latent catalysts,which are usually insoluble anionic initiators sensitive to impurities and moisture,and have many limitations in practical *** this work,a soluble thiol-terminated imidothioether oligomer(TPI) was synthesized and used as a latent hardener and modifier to prepare one-pot epoxy/thiol systems without the latent *** latent behavior and curing mechanism of epoxy systems(EP/TPI series),consisted of bisphenol A diglycidyl ether(DGEBA),pentaerythritol tetrakis(mercaptoacetate)(PETMP) and TPI,were *** thiol exchange reaction between TPI and PETMP preceded the curing reaction of DGEBA,and produced aromatic thiols,which were unreactive at ambient conditions and reacted with DGEBA to form the thermosets at temperatures above 130 ℃.At the loading of 24.4 wt%TPI,the epoxy system(EP/TPI-3) had a shelf life of 13 days and was completely cured within 20 min at 180 ℃.Meanwhile,the catalyst-free curing process of EP/TPI-3 system was insensitive to impurities and ***,the thermal and mechanical properties of EP/TPI-3 thermoset were simultaneously improved,thereinto,the glass transition temperature,young's modulus and ultimate tensile strength were increased by 16.7 ℃,12.9%,and 13.6%,respectively,compared with those of the commercial DGEBA/PETMP *** work shows that TPI has the potential to be a powerful alternative to commercial latent catalysts,and EP/TPI thermosets with high performance have broad application prospects.

关键词： thiol-terminated imidothioether oligomer epoxy systems thiol exchange reaction thermal latency high performance

Annexin A1 in the nervous and ocular systems

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Neural Regeneration Research 2024年第3期19卷 591-597页

作者： Aijia Wang Hong Zhang xing Li Yin zhao Department of Ophthalmology 2Department of AnesthesiologyTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

The therapeutic potential of Annexin A1,an important member of the Annexin superfamily,has become evident in results of experiments with multiple human systems and animal *** anti-inflammatory and pro-resolving effects of Annexin A1 are characteristic of pathologies involving the nervous *** this review,we initially describe the expression sites of Annexin A1,then outline the mechanisms by which Annexin A1 maintains the neurological homeostasis through either formyl peptide receptor 2 or other molecular approaches;and,finally,we discuss the neuroregenerative potential qualities of Annexin *** eye and the nervous system are anatomically and functionally connected,but the association between visual system pathogenesis,especially in the retina,and Annexin A1 alterations has not been well ***,we explain the beneficial effects of Annexin A1 for ocular diseases,especially for retinal diseases and glaucoma on the basis of published findings,and we explore present and future delivery strategies for Annexin A1 to the retina.

关键词： Annexin A1(ANXA1) glaucoma nervous system neuroprotection neuroregeneration ocular disease retina

Impact of Mo/Ni alloying on microstructural modulation and low-temperature toughness of high-strength low-alloy steel

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Journal of Iron and Steel Research International 2024年第7期31卷 1746-1762页

作者： Wei Liu Hong-li zhao Bing-xing Wang Yong Tian State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina

The high-strength low-alloy steel plates with varying Ni/Mo contents were manufactured using the thermos-mechanical control *** investigation was conducted to explore the effect of Ni/Mo microalloying on microstructure evolution and mechanical properties of the *** results revealed that the increase in Ni content from 1 to 2 wt.%reduced the transition temperature of ferrite and the growth range of ferritic grain was narrowed,which promoted grain *** optimized combination of grain size,high-angle grain boundaries(HAGBs),and martensite-austenite(M-A)islands parameter contributed to the excellent impact toughness of S1 steel at-100℃(impact absorbed energy of 218.2 J at-100℃).As the Mo increases from 0 to 2 wt.%,the matrix structure changes from multiphase structure to granular bainite,which increases the average effective grain size to~4.62 pm and reduces HAGBs proportion to~36.22%.With these changes,the low-temperature impact toughness of S3 steel is *** addition,based on the analysis of the characteristics of crack propagation path,it was found that M-A islands with low content(~2.21%)and small size(~1.76 pm)significantly retarded crack propagation,and the fracture model of M-A islands with different morphologies was further ***,correlation between behaviour of delamination and toughness was further analysed by observing delamination size and impact energy parameters.

关键词： High-strength low-alloy steel Microstructural regulation Ni addition Mo addition Crack propagation Low-temperature toughness

Fabrication of Biomimetic Surface for Hydrophobic and Anti-icing Purposes via the Capillary Force Lithography

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Journal of Bionic Engineering 2024年第1期21卷 74-83页

作者： Wenqiang xing Yiping Tang Fengzhou zhao Lichun Zhang Dengying Zhang School of Physics and Optoelectronic Engineering Ludong UniversityYantai 264025China

In this paper,inspired by lotus leaf surfaces,we fabricated biomimetic multi-scale micro-nano-structures by Two-Step Capillary Force Lithography(TS-CFL)and UV-assisted Capillary Force Lithography(UV-CFL).The experimental results indicated that TS-CFL was unfitted to fabricate large-area multi-scale ***,UV-CFL can fabricate large-area multi-scale *** discussed the hydrophobic and anti-icing properties of the biomimetic surfaces fabricated by these two *** found that small structures are significant for improving the hydrophobic anti-icing properties of single-structured or structureless *** believe that these results can complement the experimental details of both technologies and enable the development of more interesting micro-nano-structures biomimetic surfaces by both technologies in the future.

关键词： Capllary force lithography Biomimetic lotus leaf Multi-scale structures Hydrophobic Anti-icing