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Three-dimensional inversion of knot defects recognition in timber cutting

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Journal of Forestry Research 2023年第4期34卷 1145-1152页

作者： Yizhuo Zhang dapeng jiang Zebing Zhang Jinhao Chen College of Computer Science and Technology Changzhou UniversityChangzhou 213164People’s Republic of China College of Mechanical and Electrical Engineering Northeast Forestry UniversityHarbin 150040People’s Republic of China

The comprehensive utilization of wood is the main goal of log cutting,but knot defects increase the diffi-culty of rationally optimizing *** to the lack of real shape data of knot defects in logs,it is diffi cult for detection methods to establish a correlation between signal and defect *** image-processing method is proposed for knot inversion based on distance regularized level set segmentation(DRLSE)and spatial vertex clustering,and with the inversion of the defects existing relative board position in the log,an inversion model of the knot defect is ***,the defect edges of the top and bottom images of the boards are extracted by DRLSE and ellipse fi tting,and the major axes of the ellipses made coplanar by angle correction;second,the coordinate points of the top and bottom ellipse edges are extracted to form a spatial straight line;third,to solve the intersection dispersion of spatial straight lines and the major axis plane,K-medoids clustering is used to locate the ***,with the vertex and the large ellipse,a 3D cone model is constructed which can be used to invert the shape of knots in the *** experiment was conducted on ten defective larch boards,and the experimental results showed that this method can accurately invert the shapes of defects in solid wood boards with the advantages of low cost and easy operation.

关键词： Timber knot inversion Distance regularized level set segmentation(DRLSE) Ellipse fi tting K-medoids cluster

A novel NIRS modelling method with OPLS-SPA and MIX-PLS for timber evaluation

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Journal of Forestry Research 2022年第1期33卷 369-376页

作者： Jinhao Chen Huilig Yu dapeng jiang Yizhuo Zhang Keqi Wang College of Mechanical and Electrical Engineering Northeast Forestry UniversityHarbin 150040People’s Republic of China College of Information and Computer Engineering Northeast Forestry UniversityHarbin 150040People’s Republic of China

The identification of timber properties is important for safe *** Infrared Spectroscopy(NIRS)technology is widely-used because of its simplicity,efficiency,and positive environmental ***,in its application,weak signals are extracted from complex,overlapping and changing *** study focused on the stability of NIR *** Orthogonal Partial Least Squares(OPLS)and Successive Projections Algorithm(SPA)eliminates noise and extracts effective spectra,and an ensemble learning method MIX-PLS,is applied to establish the *** elastic modulus of timber is taken as an example,and 201 wood samples of three species,Xylosmacongesta(Lour.)Merr.,Acer pictum ***,and Betula pendula,samples were divided into three groups to investigate modelling *** results show that OPLS can preprocess the near-infrared spectroscopy information according to the target object in the face of the system error and reduce errors to *** finally selects 13 spectral bands,simplifies the NIR spectral data and improves model *** Pearson's correlation coefficient of Calibration(Rc)and the Pearson's correlation coefficient of Prediction(Rp)of Mix Partial Least Squares(MIX-PLS)were 0.95 and 0.90,and Root Mean Square Error of Calibration(RMSEC)and Root Mean Square Error of Prediction(RMSEP)are 2.075 and 6.001,respectively,which shows the model has good generalization abilities.

关键词： NIR prediction Orthogonal partial least squares(OPLS) Successive projections algorithm(SPA) Mix partial least squares(MIX-PLS)modulus of elasticity

Growth and optical properties of ytterbium and rare earth ions codoped CaF2-SrF2 eutectic solid-solution(RE=Y^(3+),Gd^(3+),La^(3+))

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Journal of Rare Earths 2021年第4期39卷 390-397页

作者： Binbin jiang Lihe Zheng dapeng jiang Handi Yin jiangang Zheng Qiuhong Yang Guofeng Cheng Liangbi Su School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 201899China School of Physics and Astronomy Yunnan UniversityKunming 650091China Laser Fusion Research Center China Academy of Engineering PhysicsMianyang 621900China Key Laboratory of Science and Technology on High Energy Laser China Academy of Engineering and PhysicsMianyang 621900China

Ytterbium and rare earth ions(RE=Y,Gd,La)codoped CaF_(2)-SrF_(2)single crystals(3 at%Yb,6 at%RE:CaF_(2)-SrF_(2))were fabricated by temperature gradient technology(TGT).All the space groups remain the same Fm3m as that of Yb:CaF_(2)-SrF_(2).The lattice parameter a,unit cell volume V,as well as bond length of Ca/Sr-F and F-F increase in the sequence of rare-earth ions radius Y^(3+)

关键词： Rare earth ions Optical materials Crystal growth Luminescence Raman spectroscopy

Analysis on electrical transport characteristic of 8-hydroquinoline aluminum film

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Chinese Science Bulletin 1998年第2期43卷 121-124页

作者： Ligong Zhang dapeng jiang Xinguang Ren Xueyan Liu Yajun Li Ande Lu Jinshan Yuan Chinese Acad Sci Changchun Inst Phys Changchun 130021 Peoples R China

The current_voltage and capacitance_voltage characteristic of the organic single_layered electroluminescent diode utilizing 8_hydroquinoline aluminum as active layer have been measured under bias ranging from -5 V to 28 V in this work. A simple model for charge transport process of 8_hydroquinoline aluminum layer is proposed to illuminate the conductivity characteristic of the diode.

关键词： hydroquinoline aluminum current-voltage characteristic capacitance-voltage characteristic.

Spectra properties of Yb^(3+),Er^(3+):Sc_2SiO_5 crystal

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Chinese Physics B 2019年第3期28卷 362-365页

作者： Yanyan Xue Lihe Zheng dapeng jiang Qinglin Sai Liangbi Su Jun Xu School of Physics Science and Engineering Institute for Advanced StudyTongji University Shanghai Institute of Ceramics Chinese Academy of Sciences Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai Engineering Research Center for Sapphire Crystals

The influence of Er3+ ions on the spectra of Yb^(3+),Er^(3+): Sc_2 SiO_5(SSO) single crystal, which was obtained by Czochralski(Cz) method, is discussed. The absorption coefficient at 980 nm was 13.36 cm^(-1) with a peak absorption cross-section of 1.46 × 10^(-20) cm2. The emission cross-sections at 1034 nm and 1062 nm were 5.5 × 10^(-21) cm^2 and4.9 × 10^(-21) cm^2, respectively. The fluorescence lifetime was estimated as 1.24 ms at 1061 nm. The mechanical properties of SSO single crystal were also presented.

关键词： Yb3+ Er3+: Sc2SiO5 spectra properties mechanical properties

Enhanced Thermal Conductivity and Bending Strength of Graphite Flakes/aluminum Composites Via Graphite Surface Modification

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Journal of Wuhan University of Technology(Materials Science) 2020年第1期35卷 9-15页

作者：蒋大鹏 ZHU Xiaomin YU Jiakang State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Xi’an Microelectronic Technology Institute Xi’an 710072China

The effect of graphite surface modification on the thermal conductivity(TC) and bending strength of graphite flakes/Al composites(Gf/Al) prepared by gas pressure infiltration were investigated. Al3 Ni and Al4C3 phase may form at the interface in Ni-coated Gf/Al and uncoated Gf/Al composites, respectively, while the Al-Cu compound cannot be observed in Cu-coated Gf/Al composites. The Cu and Ni coatings enhance TC and the bending strength of the composites in the meantime. TC of Cu-coated Gf/Al composites reach 515 Wm^-1·K^-1 with 75 vol% Gf, which are higher than that of Ni-coated Gf/Al. Meanwhile, due to Al3 Ni at the interface, the bending strength of Ni-coated Gf/Al composites are far more than those of the uncoated and Cu-coated Gf/Al with the same content of Gf. The results indicate that metal-coated Gf can effectively improve the interfacial bonding between Gf and Al.

关键词： graphite flakes/Al composites metal coating thermal conductivity bending strength

Development of an Inexpensive Decentralized Autonomous Aquatic Craft Swarm System for Ocean Exploration

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Journal of Marine Science and Application 2019年第3期18卷 343-352页

作者： Runlong Miao Shuo Pang dapeng jiang National Key Laboratory of Autonomous Underwater Vehicle College of Shipbuilding Engineering Harbin Engineering University

Swarm robotics in maritime engineering is a promising approach characterized by large numbers of relatively small and inexpensive autonomous aquatic crafts (AACs) to monitor marine environments. Compared with a single, large aquatic manned or unmanned surface vehicle, a highly distributed aquatic swarm system with several AACs features advantages in numerous real-world maritime missions, and its natural potential is qualified for new classes of tasks that uniformly feature low cost and high efficiency through time. This article develops an inexpensive AAC based on an embedded-systemcompanion computer and open-source autopilot, providing a verification platform for education and research on swarm algorithm on water surfaces. A topology communication network, including an inner communication network to exchange information among AACs and an external communication network for monitoring the state of the AAC Swarm System (AACSS), was designed based on the topology built into the Xbee units for the AACSS. In the emergence control network, the transmitter and receiver were coupled to distribute or recover the AAC. The swarm motion behaviors in AAC were resolved into the capabilities of go-to-waypoint and path following, which can be accomplished by two uncoupled controllers: speed controller and heading controller. The good performance of velocity and heading controllers in go-to-waypoint was proven in a series of simulations. Path following was achieved by tracking a set of ordered waypoints in the go-to-waypoint. Finally, a sea trial conducted at the China National Deep Sea Center successfully demonstrated the motion capability of the AAC. The sea trial results showed that the AAC is suited to carry out environmental monitoring tasks by efficiently covering the desired path, allowing for redundancy in the data collection process and tolerating the individual AACs’ path-following offset caused by winds and waves.

关键词： Marine environment monitoring Swarm robotics Autonomous aquatic craft Unmanned surface vehicles Autonomous aquatic craft swarmsystem Decentralized control

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我国战略性新兴产业的现状分析

科技进步与对策 2010年第17期27卷 65-70页

作者：姜大鹏顾新四川大学工商管理学院四川成都610064

分析了战略性新兴产业与其它产业间的区别和联系,介绍了我国战略性新兴产业的发展现状,指出了发展过程中存在的问题,并提出了解决问题的对策。

关键词：战略性新兴产业发展现状高技术产业

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泌尿系统不同部位来源特络细胞的研究进展

中华小儿外科杂志 2020年第4期41卷 382-384,F0003页

作者：王琪姜大朋上海交通大学医学院附属儿童医学中心小儿泌尿外科 200120

特络细胞(Telocytes,TCs)是一种特殊类型的间质细胞,其有小胞体和1~5个(2~3个常见)极长而薄的细胞突起(Telopodes,Tps)。TCs存在于多种器官与组织中,其特殊的形态结构和组织分布特征与器官或组织的生理功能和病理改变有关。迄今为止,在... 详细信息

特络细胞(Telocytes,TCs)是一种特殊类型的间质细胞,其有小胞体和1~5个(2~3个常见)极长而薄的细胞突起(Telopodes,Tps)。TCs存在于多种器官与组织中,其特殊的形态结构和组织分布特征与器官或组织的生理功能和病理改变有关。迄今为止,在肾、膀胱、输尿管、尿道等组织中也发现TCs,其可通过Tps在间质空间形成错综复杂的3D网络,使TCs与其他细胞相联系,并可通过释放信号分子,向邻近细胞传递化学信号;TCs还可能具有干细胞潜能,或为干细胞的支持细胞。TCs可能在维持泌尿系统生理稳态和促进器官再生方面有巨大潜能。

关键词：再生医学特络细胞泌尿系统细胞外囊泡