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Visible characteristics of space-based targets based on bidirectional reflection distribution function

Science China(Technological Sciences) 2012年第4期55卷 982-989页

作者： wang hongyuan ZHANG Wei wang FuGang Research Center for Space Optical Engineering Harbin Institute of TechnologyHarbin 150001China

A precise modeling method of visible characteristics of the space-based target was presented based on bidirectional reflection distribution function (BRDF). The background characteristics of the space-based target were represented to build models of direct solar radiation and reflected radiation of the Earth based on blackbody radiation theory. The geometry characteristics of the target were analyzed to establish a surface equation of each surface based on its body coordinate system. The material characteristics of the target surface were described by introducing a BRDF model which considers the character of surface Gauss statistics and self-shadow and is obtained by measurement and modeling in advance. The relative positions of the space-based target, the background radiation sources and the observation platform were determined based on coordinate con- version to judge contributing surface of the target to observation system. Then a mathematical model on visible characteristics of the space target for the given optical system was built by summing reflection components of all the surfaces. Simulation of visible characteristics of the space-based target in orbit was achieved according to its given geometrical dimensions, physical parameters and orbital parameters. The results show that the method is effective for analysis on visible characteristics of the space-based target when single reflection is considered and its surface is regularly described in a surface equation, which provides a way to real-time calculation of visible characteristics of the space-based target.

关键词： space optics space-based target visible characteristics bidirectional reflection distribution function (BRDF)

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Filtering and regret network for spacecraft component segmentation based on gray images and depth maps

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Chinese Journal of Aeronautics 2024年第7期37卷 439-449页

作者： Xiang LIU hongyuan wang Zijian wang Xinlong CHEN Weichun CHEN Zhengyou XIE Institute of Aeronautics Harbin Institute of TechnologyHarbin 150001China Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijing 100080China

Identifying and segmenting spacecraft components is vital in many on-orbit space missions,such as on-orbit maintenance and component *** depth maps with visual images has been proven effective in improving segmentation ***,existing methods ignore the noise and fallacy in collected depth maps,which interfere with the network to extract representative features,decreasing the final segmentation *** this end,this paper proposes a Filtering and Regret Network(FRNet)for spacecraft component *** FRNet incorporates filtering and regret mechanisms to suppress the abnormal depth response in shallow layers and selectively reuses the filtered cues in deep layers,avoiding the detrimental effects of low-quality depth information while preserving the semantic context inherent in depth ***,a two-stage feature fusion module is proposed,which involves information interaction and *** module effectively explores the feature correlation and unifies the multimodal features into a comprehensive ***,a large-scale spacecraft component recognition dataset is constructed for training and evaluating spacecraft component segmentation *** results demonstrate that the FRNet achieves a state-of-the-art performance with a mean Intersection Over Union(mIOU)of 84.13%and an average inference time of 133.2 ms when tested on an NVIDIA RTX 2080 SUPER GPU.

关键词： Spacecraft component recognition Multi-modal feature fusion Satellite dataset Intelligent systems Deep learning

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Histological Architecture of the Nasal Region in Rana chensinensis

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Asian Herpetological Research 2013年第1期4卷 68-75页

作者： hongyuan wang Zhouxian SANG Gang LIANG College of Life Science Shaanxi Normal University

The nasal region of Rana chensinensis is divided into the nasal capsules and nasal cavities. In this study, we investigated the adult histological structure of the nasal capsules and nasal cavities in the frog R. chensinensis under the microscope. We found that an eminentia olfactoria is present in this frog and the presence of the eminentia olfactoria may be connected to a terrestrial life style. The double staining method using alcian blue and alizarin red showed that the septomaxilla, the most important bone associated with the olfactory capsules, is an intramembranous bone in R. chensinensis. The opening of the nasolacrimal duct showed a close proximity to the apertura nasalis externa. The presence of the nasolacrimal duct in the olfactory region may be an adaptation to a terrestrial environment. The function of the vomeronasal and olfactory organs is discussed in the paper.

关键词： frog Rana chensinensis olfactory organ vomeronasal organ skeletal morphology

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Discussion on Sustainable Urbanization in Tibet

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Chinese Geographical Science 2010年第3期20卷 258-268页

作者： FAN Jie wang hongyuan CHEN Dong ZHANG Wenzhong wang Chuansheng Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

After 1995, Tibet entered the stage of accelerated urbanization. The large floating population fi＇om outside Tibet has become the driving force for urban expansion and the rising of urbanization rate. After analyzing the changes of urban functions and spatial structure of urban system in Tibet, this paper argues that before 1995 the urbanization in Tibet was mainly driven by administrative function, resulting in certain population migration, whereas in the past decade economic function has become the key factor accelerating urban expansion with the market mechanism creating large-scale inflow of population. The floating population-based urbanization and high population growth in the agricultural and pastoral areas of Tibet has promoted the regional economic prosperity, but exerted resources and environmental pressure and brought some problems for Tibetan culture protection at the same time. The conflicts and contradictions between urbanization and the sustainability of natural resources, environment and social development have been intensified. Addressing these problems, this paper proposes some countermeasures for improving the sustainability of Tibetan urbanization.

关键词： urbanization population resources environment sustainability Tibet

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Simultaneous optical and electrochemical recording of single nanoparticle electrochemistry

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Nano Research 2017年第5期10卷 1740-1748页

作者： Linlin Sun Yimin Fang Zhimin Li Wei wang hongyuan Chen State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical Engineering Nanjing UniversityNanjing 210093 China

Single nanoparticle collisions have become popular for studying the electro- chemical activity of single nanoparticles by determining the transient current during stochastic collisions with the electrode surface. However, if only the electrochemical current is measured, it remains challenging to identify and characterize the individual particle that is responsible for a specific current peak in a collision event; this hampers the understanding of the structure-activity relationship. Herein, we report simultaneous optical and electrochemical recording of a single nanoparticle collision; the electrochemical signal corresponds with the activity of a single nanoparticle, and the optical signal reveals the size and location of the same nanoparticle. Consequently, the structure （optical signal）- activity （electrochemical signal） relationship can be elucidated at the single nanoparticle level; this has implications for various applications including batteries, electrocatalysts, and electrochemical sensors. In addition, our previous studies have suggested an optical-to-electrochemical conversion model to independently calculate the electron transfer rate of single nanopartides from the optical signal. The simultaneous optical and electrochemical recording achieved in the present work enables direct and quantitative validation of the optical-to-electrochemical conversion model.

关键词： single nanoparticlecollision surface plasmonresonance microscopy plasmonics-basedelectrochemicalmicroscopy Ag nanoparticles

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Spatial and seasonal variations in bacterial communities of the Yellow Sea by T-RFLP analysis

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Frontiers of Environmental Science & Engineering 2009年第2期3卷 194-199页

作者： hongyuan wang Xiaolu JIANG Ya HE Huashi GUAN School of Medicine and Pharmacy Ocean University of ChinaQingdao 266003China Institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural ScienceBeijing 100081China School of Environment Beijing Normal UniversityBeijing 100875China

Four typical coastal sites(rocky shore,sandy shore,mud flat shore,and artificial harbor)at the Yellow Sea were chosen to investigate the spatial and seasonal variations in bacterial *** was accomplished by using terminal restriction fragment length polymorphism(T-RFLP)analysis of PCR amplified 16S rDNA *** kinds of tetrameric restriction enzymes,HhaI and MspI,were used in the experiment to depict the bacterial community diversity in different marine *** was found that the community compositions digested by the two enzymes separately were ***,the results of bacterial community diversity derived from them were *** MDA analysis results of T-RFLP profiles coming from HhaI and MspI both exhibited a significant seasonal community shift for bacteria and a relatively low spatial variation among the four *** HhaI as the sample,the pair wise Ttests also revealed that variations were minor between each pair of marine environments,with R ranging from 0.198 to ***,the bacterial community structure in the mud flat site depicted a larger difference than each of the other three sites(R ranging from 0.282 to 0.349).

关键词： terminal restriction fragment length polymorphism(T-RFLP) bacterial community structure marine microbial diversity HhaI MspI

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A precision-drive hysteresis model with an equal-density weight function for GMA feedforward compensation

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Nanotechnology and Precision Engineering 2023年第2期6卷 13-24页

作者： Kun Xiao Zhiwen wang hongyuan wang Jie Sun Yelong Zheng Yinguo Huang State Key Laboratory of Precision Measuring Technology and Instruments Tianjin UniversityTianjin 300072China

Giant magnetostrictive actuators(GMAs) are a widely used type of micro-nano actuator, and they are greatly significant in the field of precision engineering. The accuracy of a GMA often depends on its hysteresis model. However, existing models have some limitations,including the difficulty of identifying their parameters and the tradeoff between the quantity of modeling data required and the level of precision achieved. To solve these problems, in this paper, we propose a Preisach inverse model based on equal-density segmentation of the weight function(E-Preisach). The weight function used to calculate the displacement is first discretized. Then, to obtain a finer weight distribution, the discretized geometric units are uniformly divided by area. This can further minimize the output displacement span, and it produces a higher-precision hysteresis model. The process of parameter identification is made easier by this approach, which also resolves the difficulty of obtaining high precision using a small amount of modeling data. The Preisach and the E-Preisach inverse models were investigated and compared using experiments. At frequencies of 1 and 5 Hz, it was found that the E-Preisach inverse model decreases the maximum error of the feedforward compensation open-loop control to within 1 μm and decreases the root-mean-square error in displacement to within0.5 μm without the need to increase the number of measured hysteresis loops. As a result, the E-Preisach inverse model streamlines the structure of the model and requires fewer parameters for modeling. This provides a high-precision modeling method using a small amount of modeling data;it will have applications in precision engineering fields such as active vibration damping and ultra-precision machining.

关键词： Micro-nano actuator GMA Hysteresis model Preisach model

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Study on Model of Ash Fouling Monitoring in Rotary Air Preheater of Coal-fired Power Plant Boiler 36

Study on Model of Ash Fouling Monitoring in Rotary Air Prehe...

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第36届中国控制会议

作者： Ziyang Wei Jingcheng wang hongyuan wang Department of Automation Shanghai Jiao Tong Universityand Key Laboratory of System Control and Information ProcessingMinistry of Education of China Autonomous Systems and Intelligent Control International Joint Research Center Xi'an Technological University

ISBN: (纸本)9781538629185

As an important equipment to preheat air and to improve coal-fired power plant boiler efficiency with the heat of boiler tail flue gas,the air preheater’s safe and economic operation influences unit efficiency *** present,above 80%utility-type unit in domestic uses tri-sectional rotary air ***,the rotary air preheater has become an indispensable auxiliary machinery in modern large ***,a kind of air preheater heat transfer model of inverse flue gas flow is proposed in this paper,the ash fouling situation of air preheater is showed with the cleanliness factors based on heat transfer model and flue gas pressure drop model ***,the cleanliness factor of air preheater is calculated and gained through thermodynamics indirectly with energy balance *** to the verification results of the actual operation data of a 600 MW coal-fired unit,both of these two kinds of mode can reflect the dynamic change of ash fouling situation of air preheater in real time,and among which,the cleanliness factor based on flue gas pressure drop mode has a better online monitoring result on ash fouling situation of heat transfer surface.

关键词： Coal-fired Power Plant Boiler Tri-sectional Rotary Air Preheater Reverse Flue Gas Flow Ash Fouling Cleanliness Factor

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Temporal Spreading Effect of Oceanic Lidar System

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Wuhan University Journal of Natural Sciences 2007年第3期12卷 501-505页

作者： ZHAN Enqi wang hongyuan Department of Electronic and Information Engineering Huazhong University of Science and Technology Wuhan 430074 Hubei China School of Information Engineering Wuhan University of Technology Wuhan 430070 Hubei China

In this paper, multipath temporal spreading distributions of laser pulses are calculated when they travel through the seawater. Individual photon is followed in Monte Carlo calculation A modified Henyey-Greenstein （HG） function is applied to represent the scattering phase function of seawater. This paper proposes a new scaling method, which uses the effective scattering thickness τd to replace the optical thickness used in the traditional scaling technique. This paper compares the temporal spreading distributions of photons on conditions of different attenuation coefficients and target depths. The experiments reveal that these mutual deviations are changing in the range from 0.5% to 5%, so long as the corresponding effective scattering thicknesses τd remains the same. Therefore, a conclusion can be obtained, that the temporal spreading distribution is only dependent on the effective diffusion thickness τd .

关键词： multipath temporal spreading scattering phase function effective diffusion thickness Monte Carlo calculation

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Efficient tracker based on sparse coding with Euclidean local structure-based constraint

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智能系统学报 2016年第1期11卷 136-147页

作者： wang hongyuan ZHANG Ji CHEN Fuhua School of Information Science and Engineering Changzhou University Department of Natural Science and Mathematics West Liberty University

Abstract:Sparse coding(SC)based visual tracking(l1-tracker)is gaining increasing attention,and many related algorithms are *** these algorithms,each candidate region is sparsely represented as a set of target ***,the structure connecting these candidate regions is usually *** proposed an NLSSC-tracker with non-local self-similarity sparse coding to address this issue,which has a high computational *** this study,we propose an Euclidean local-structure constraint based sparse coding tracker with a smoothed Euclidean local *** this tracker,the optimization procedure is transformed to a small-scale l1-optimization problem,significantly reducing the computational *** experimental results on visual tracking demonstrate the eectiveness and efficiency of the proposed algorithm.

关键词： euclidean local-structure constraint l1-tracker sparse coding target tracking

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