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Radiation dose detection using a high-power portable optically stimulated luminescence real-time reading system

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Nuclear Science and Techniques 2018年第10期29卷 245-253页

作者： Yi-Hang Wang Hua chen fei chen Yong-Gang yuan Tai-Ping Peng Institute of Nuclear Physics and Chemistry Chinese Academy of Engineering Physics

Optically stimulated luminescence(OSL) reading systems are becoming smaller and capable of real-time detection. To improve real-time and multipurpose radiation dosimetry readings, we built a real-time continuous-wave(RCW) OSL reading system. This system is both small and lightweight, and it employs powerful laser excitation(478 mW/cm^2) at the dosimetry probe location. We investigate the possibility of using the RCW mode to read the radiation luminescence(RL) or OSL by using a singlecrystal Al_2O_3:C dosimeter in a low-dose-rate137 Cs y *** results indicate that the RL/OSL follows a stable and uniform distribution. The minimum detected doses associated with the RL, OSL, and RL + OSL signals are2.1 9 10^(-2), 3.17 9 10^(-1), and 5.7 9 10^(-2) l Gy, respectively. This device provides a framework for the future development of applications for practical radiation dose measurements.

关键词： OSL Real-time reading Al2O3:C Radiation dose

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基于边缘引导与特征融合的分阶段图像去模糊

光电子·激光 2025年第1期36卷 17-26页

作者：陈清江邵菲王炫钧西安建筑科技大学理学院

针对现有方法去模糊后图像缺乏足够清晰边缘的问题，提出了一种基于边缘引导与特征融合的分阶段图像去模糊方法，分两个阶段逐步去除模糊。首先，第一阶段应用含双交叉集成注意力模块(dual cross integrated attention module, DCIAM)... 详细信息

针对现有方法去模糊后图像缺乏足够清晰边缘的问题，提出了一种基于边缘引导与特征融合的分阶段图像去模糊方法，分两个阶段逐步去除模糊。首先，第一阶段应用含双交叉集成注意力模块(dual cross integrated attention module, DCIAM)的编解码网络学习不同尺度下图像的内容特征，初步去除模糊信息。然后，构建边缘分支网络(edge branch network, EBN)提取图像边缘特征。再次，设计了边缘引导去模糊模块(edge-guided deblurring module, EGDM)以耦合不同分辨率下图像的内容与边缘特征。最后，第二阶段通过级联的残差块和DCIAM进一步去除图像模糊，并通过引入自校准注意融合模块(self-calibrating attention fusion module, SCAFM)增强特征表达效果。实验结果表明：所提方法去模糊后图像的峰值信噪比和结构相似度均值分别达到32.78 dB和0.964,均优于其他对比方法。所提方法可以显著提高去模糊性能且去模糊后图像边缘结构更加完整。

关键词：图像去模糊边缘引导特征融合多尺度框架注意力机制

Impact of Vocal Fold Dehydration on Vocal Function and Its Treatment

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Current Medical Science 2019年第2期39卷 310-316页

作者： Zhe-fei ZOU Wei chen Wei LI Kun yuan Department of Otolaryngology-Head and Neck Surgery The Central Hospital of WuhanTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430014China Hubei Cancer Hospital Wuhan 430014China

The change of vocal flinction after vocal fold dehydration due to dryness was discussed along with the treatment eHect of different atomizing ***-eight staffs from The Central Hospital of Wuhan were *** volunteers breathed dry air for vocal fold *** dry air inhalation,the subjects were randomly divided into four groups,with 12 cases *** groups were treatment groups,receiving 0.9%nonnal saline(IS),5%hypertonic saline(HS)and double-distilled water(SW)atomizing inhalation therapy,respectively,and the last group was the control group without *** data were collected for all subjects before and immediately after dry air inhalation using the Multi-Dimensional Voice Program(MDVP)*** inhalation therapy was given 10 min after dry air inhalation,and voice data were collected using MDVP system at the following time points after atomizing inhalation treatment:5 min,20 min,35 min,50 min,65 min,80 min,95 min,110 *** the control group,voice data were collected at the same time points and compared with those of treatment *** vocal function parameters collected before and after dry air inhalation as well as after treatment were subjected to test using SPSS 16.0 *** the four groups,jitter(fundamental frequency perturbation),shimmer(amplitude perturbation),and amplitude perturbation quotient(APQ)were significantly increased after dry air inhalation(P<0.05).In IS,HS and SW groups,after atomizing inhalation treatment,there was an obvious reduction in jitter,shimmer and APQ,showing significant differences as compared with those after dry air inhalation(P<0.05).Moreover,these parameters were significantly lower than those in the control group(P<0.05).The jitter,shimmer and APQ in the IS group were significantly lower than those in the HS and SW groups(P<0.05).We are led to a con elusion:Vocal fold dehydration induced by dryness can reduce the stability of voice;such decreased voice stability can be improved

关键词： dryness vocal fold dehydration vocal function Multi-Dimensional Voice Program atomizing inhalation

Exploiting a depth context model in visual tracking with correlation filter

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Frontiers of Information Technology & Electronic Engineering 2017年第5期18卷 667-679页

作者： Zhao-yun chen Lei LUO Da-fei HUANG Mei WEN Chun-yuan ZHANG College of Computer National University of Defense TechnologyChangsha 410073China National Key Laboratory of Parallel and Distributed Processing Changsha 410073China

Recently correlation filter based trackers have attracted considerable attention for their high computational efficiency. However, they cannot handle occlusion and scale variation well enough. This paper aims at preventing the tracker from failure in these two situations by integrating the depth information into a correlation filter based tracker. By using RGB-D data, we construct a depth context model to reveal the spatial correlation between the target and its surrounding regions. Furthermore, we adopt a region growing method to make our tracker robust to occlusion and scale variation. Additional optimizations such as a model updating scheme are applied to improve the performance for longer video sequences. Both qualitative and quantitative evaluations on challenging benchmark image sequences demonstrate that the proposed tracker performs favourably against state-of-the-art algorithms.

关键词： Visual tracking Depth context model Correlation filter Region growing

Analyzing the Effect of the Intra-Pixel Position of Small PSFs for Optimizing the PL of Optical Subpixel Localization

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Engineering 2023年第8期27卷 140-149页

作者： Haiyang Zhan fei Xing Jingyu Bao Ting Sun Zhenzhen chen Zheng You Li yuan Department of Precision Instrument Tsinghua UniversityBeijing 100084China State Key Laboratory of Precision Measurement Technology and Instruments Tsinghua UniversityBeijing 100084China Beijing Advanced Innovation Center for Integrated Circuits Tsinghua UniversityBeijing 100084China Joint International Research Laboratory of Advanced Photonics and Electronics Beijing Information Science and Technology UniversityBeijing 100192China Beijing Institute of Control Engineering Beijing 100190Chin

Subpixel localization techniques for estimating the positions of point-like images captured by pixelated image sensors have been widely used in diverse optical measurement *** unavoidable imaging noise,there is a precision limit(PL)when estimating the target positions on image sensors,which depends on the detected photon count,noise,point spread function(PSF)radius,and PSF’s intra-pixel *** studies have clearly reported the effects of the first three parameters on the PL but have neglected the intra-pixel position ***,we develop a localization PL analysis framework for revealing the effect of the intra-pixel position of small *** accurately estimate the PL in practical applications,we provide effective PSF(e PSF)modeling approaches and apply the Cramér–Rao lower *** on the characteristics of small PSFs,we first derive simplified equations for finding the best PL and the best intra-pixel region for an arbitrary small PSF;we then verify these equations on real ***,we use the typical Gaussian PSF to perform a further analysis and find that the final optimum of the PL is achieved at the pixel boundaries when the Gaussian radius is as small as possible,indicating that the optimum is ultimately limited by light ***,we apply the maximum likelihood *** combination with e PSF modeling allows us to successfully reach the PL in experiments,making the above theoretical analysis *** work provides a new perspective on combining image sensor position control with PSF engineering to make full use of information theory,thereby paving the way for thoroughly understanding and achieving the final optimum of the PL in optical localization.

关键词： Optical measurement Subpixel localization Precision limit optimization Small point spread functions Centroiding Star sensors

GNSS autonomous navigation method for HEO spacecraft

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High Technology Letters 2020年第2期26卷 188-195页

作者： yuan Dehu Sun Jun Han fei chen Yang chen Yun Shanghai Aerospace Control Technology Institute Shanghai 201109P.R.China Shanghai Key Laboratory of Space Intelligent Control Technology Shanghai 201109P.R.China

For global navigation satellite system(GNSS)in the application of high earth orbit(HEO)determination,there are problems such as small number of visible satellites and weak signal *** transmitting and receiving errors of GNSS signal in the environment of HEO space are analyzed,and related compensating scheme is also *** of GNSS signal is implemented by using weak signal acquisition technology based on *** tracking of weak GNSS signal is also realized by adopting dynamic detection and compensation technology based on Duffing chaotic *** results show that,certain acquisition sensitivity and navigation precision can be reached,and the acquisition and tracking of weak GNSS signal can be realized by using the proposed technology,which provides good technology support for autonomous navigation of HEO and large elliptical spacecrafts.

关键词： global navigation satellite system(GNSS) high earth orbit(HEO) chaotic oscillator autonomous navigation

Enhancing thermal stability and photoluminescence of red-emitting Sr_(2)Si_(5)N_(8):Eu phosphors via boron doping

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Journal of Materials Science & Technology 2021年第35期94卷 130-135页

作者： Hailong yuan Zhifeng Huang Jianwen Zhang Ziqian Yin Xiangyu Lu fei chen Qiang Shen State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Department of Materials Science and Engineering Monash UniversityMelbourneVIC 3800Australia

Surface passivation is a common method to improve the resistance of thermal degradation of nitride ***,such a surface passivation generally needs extra processes and decreases the photoluminescence property of the *** this work,both the thermal stability and photoluminescence property of a red phosphor Sr_(2)Si_(5)N_(8):Eu are improved through the addition of *** influence of B on the crystal structure and the valence state of active ions was analyzed by experimental ***-principles calculations were applied to analyze the formation energy of N vacancies,which influence the resistance of thermal ***,combining with experimental characterization and calculations,the enhancing mechanism of thermal stability and photoluminescence by B was studied.

关键词： Nitride phosphors Thermal degradation Red-emitting First-principles calculations Photoluminescence

Challenges of the Sensor Web for disaster management

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International Journal of Digital Earth 2010年第3期3卷 260-279页

作者： fei Wang Hongyong yuan Center for Public Safety Research Department of Engineering PhysicsTsinghua UniversityBeijing 100084P.R.China

Sensor Web has been widely promoted and its application has evolved from original military usages to current ubiquitous civil and commercial *** emergence has become a great strength to facilitate the Digital Earth *** many Sensor Web applications and methods have been proposed to assist disaster management,they are not well suited to the unique features and application requirements of disaster *** researches focus on how to use the Sensor Web to monitor a certain phenomenon before a disaster happens and to provide early ***,there is a lack of study on the negative effects that a disaster may bring to the Sensor *** example,severe weather conditions,damaged infrastructure,and spatial isolation may directly make the Sensor Web ***,disaster management is a complex subject and its domain knowledge needs to be *** this paper,the domain of the disaster management is explored and its unique features are *** the Sensor Web concept and its role in disaster management are ***,the challenges of the Sensor Web for disaster management and the possible solutions are *** on the above,we introduce a high-mobility emergency system to demonstrate a good solution of the Sensor Web for multipurpose disaster management.

关键词： Digital Earth disaster management Sensor Web GIS Internet of Things

Entry of severe fever with thrombocytopenia syndrome virus

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Virologica Sinica 2017年第1期32卷 44-50页

作者： fei yuan Aihua Zheng CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of Microbiology Chinese Academy of Sciences State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of Sciences

Severe fever with thrombocytopenia syndrome virus （SFTSV） is a globe-shaped virus covered by a dense icosahedral array of glycoproteins Gn/Gc that mediate the attachment of the virus to host cells and the fusion of viral and cellular membranes. Several membrane factors are involved in virus entry, including C-type lectins and nonmuscle myosin heavy chain IIA. The post-fusion crystal structure of the Gc protein suggests that it is a class II membrane fusion protein, similar to the E/E1 protein of flaviviruses and alphaviruses. The virus particles are internalized into host cell endosomes through the clathrin-dependent pathway, where the low pH activates the fusion of the virus with the cell membrane. With information from studies on other bunyaviruses, herein we will review our knowledge of the entry process of SFTSV.

关键词： severe fever with thrombocytopenia syndrome virus (SFTSV) bunyavirus entry fusion receptor