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Multi-digital Still Cameras with CCD
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作者 LIU Wen-jing LONG Zai-chuan +1 位作者 XIONG Ping HUAN Yao-xiong 《Semiconductor Photonics and Technology》 CAS 2006年第2期136-138,144,共4页
Digital still camera is a completely typical tool for capturing the digital images. With the development of IC technology and optimization-algorithm, the performance of digital still cameras(DSCs) will be more and mor... Digital still camera is a completely typical tool for capturing the digital images. With the development of IC technology and optimization-algorithm, the performance of digital still cameras(DSCs) will be more and more powerful in the world. But can we obtain the more and better info using the combined information from the multi-digital still camera? The answer is yes by some experiments. By using multi-DSC at different angles, the various 3-D informations of the object are obtained. 展开更多
关键词 INFORMATION digital-image Multi-digital camera ccd
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A Method to Improve Photographing Function of Common Digital Camera to Small Flowers and Fruits 被引量:1
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作者 洪亚平 张亚冰 《Agricultural Science & Technology》 CAS 2009年第6期105-107,共3页
[ Objective] The aim of this study was to solve the problem of photographing small flowers and fruits with a common digital camera in field. [Method] Firstly, the photographic mode of a common digital camera was set ... [ Objective] The aim of this study was to solve the problem of photographing small flowers and fruits with a common digital camera in field. [Method] Firstly, the photographic mode of a common digital camera was set as "macro" (or "soft snap" ) and "flash off". Secondly, the small flower or fruit was magnified with a magnifying glass, and then the magnified flower or fruit was automatically focused with the digital camera lens. After automatic focusing, the shutter button was pressed and the photograph finished. [Result] With this method, the clear inflo- rescence or floral photographs of Eragrostis pilosa ( Gramineae ) , Bidens biternata (Compositae) and Tribulus terrester (Zygophllaceae) were obtained in field. [ Conclusion] The optical system of a digital camera has been changed by the magnifying glass, which improves the photographic function of a common digital camera to small flowers and fruits, and also easily gets their clear photographs. 展开更多
关键词 digital camera Magnifying glass Photographing FLOWER FRUIT
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Estimation of Fractional Vegetation Cover Based on Digital Camera Survey Data and a Remote Sensing Model 被引量:6
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作者 HU Zhen-qi HE Fen-qin +4 位作者 YIN Jian-zhong LU Xia TANG Shi-lu WANG Lin-lin LI Xiao-jing 《Journal of China University of Mining and Technology》 EI 2007年第1期116-120,共5页
The objective of this paper is to improve the monitoring speed and precision of fractional vegetation cover (fc). It mainly focuses on fc estimation when fcmax and fcmin are not approximately equal to 100% and 0%, res... The objective of this paper is to improve the monitoring speed and precision of fractional vegetation cover (fc). It mainly focuses on fc estimation when fcmax and fcmin are not approximately equal to 100% and 0%, respectively due to using remote sensing image with medium or low spatial resolution. Meanwhile, we present a new method of fc estimation based on a random set of fc maximum and minimum values from digital camera (DC) survey data and a di- midiate pixel model. The results show that this is a convenient, efficient and accurate method for fc monitoring, with the maximum error -0.172 and correlation coefficient of 0.974 between DC survey data and the estimated value of the remote sensing model. The remaining DC survey data can be used as verification data for the precision of the fc estimation. In general, the estimation of fc based on DC survey data and a remote sensing model is a brand-new development trend and deserves further extensive utilization. 展开更多
关键词 fractional vegetation cover digital camera survey data dimidiate pixel model
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An Introduction to 2-CCD Digital Particle Image Velocimetry System and Its Application in Ocean Engineering 被引量:1
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作者 Daichin Timothy P.Dewhirst 《China Ocean Engineering》 SCIE EI 1997年第3期347-356,共10页
The basic principle of particle image velocinmetry (PIV) is described. When a PIV image is analyzed by the method of auto-correlation, there is a direction ambiguity of 180 degrees iii velocity measurement. The proble... The basic principle of particle image velocinmetry (PIV) is described. When a PIV image is analyzed by the method of auto-correlation, there is a direction ambiguity of 180 degrees iii velocity measurement. The problem can be solved by using 'Image Shifting Technique', but this makes devices much complicated and difficult to control. A new arrangement of 2-CCD (Charge Coupled Device) fully digitized PIV system, which can also solve the problem successfully, is introduced in the paper. As an example of application of the system, an experimental result of flow field around a horizontal cylinder in wave is presented. 展开更多
关键词 particle image velocimetry ccd camera CROSS-CORRELATION
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CCD signal acquisition and optimal digital denoise technology 被引量:1
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作者 Li Wencan Wen Yan +1 位作者 Wang Dong Yao Dalei 《High Technology Letters》 EI CAS 2021年第4期422-429,共8页
To reduce the charge-coupled device(CCD)readout noise and improve the detection ability under low illumination and dim targets,a new low-noise CCD signal processing technology-CCD digital denoiseis gradually being emp... To reduce the charge-coupled device(CCD)readout noise and improve the detection ability under low illumination and dim targets,a new low-noise CCD signal processing technology-CCD digital denoiseis gradually being employed in aerospace detection and other fields.In this study,the main readout noise of CCD detectors and its characteristics are analyzed.A CCD digital denoise system and an experimental platform are designed as well as established by using a PCIe data acquisition card.According to the characteristics of readout noise,some digital filters are analyzed and designed based on distributed kernel coefficient,and the optimal kernel coefficients are obtained through iteration.Then,CCD signal and filter model are established,and the optimal filter is designed to apply to the digital denoise system.Finally,according to the image data obtained from the system,the performance of the digital denoise system and digital filtering algorithm is evaluated and compared.At 500 kHz and 1 MHz CCD readout rates,the denoising performance of the optimal filter designed in the experiment is 16%-32%higher than that of the digital filter with kernel distribution coefficient,and 50%-60%higher than that of the traditional correlated double sampling technology. 展开更多
关键词 charge-coupled device(ccd) low noise reset noise digital correlated double sampling optimal filter
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Positioning of Screw Holes Group Based on Digital Camera and Digital Control Drilling
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作者 FENGWenhao LIJiansong YANLi SUGuozhong YUANXiuxiao ZHONGShengzhang JIHuiming 《Geo-Spatial Information Science》 2004年第4期235-242,共8页
Positioning of screw holes is an important production procedure for steel construction connecting with bolts. In this paper, a new production method is presented, in which the digital camera is used for taking picture... Positioning of screw holes is an important production procedure for steel construction connecting with bolts. In this paper, a new production method is presented, in which the digital camera is used for taking pictures of screw holes and other techniques are advanced. This paper also indicates that the pixels of CCD chip in photogrammetry should be chosen as all geometric units in an image, such as interior elements and all kinds of distortions. The measure can also simplify the camera calibration for determining the size of non-square pixel. 展开更多
关键词 digital camera screw hoies digital drilling machine PHOTOGRAMMETRY multi-station photo- grammetry SELF-CALIBRATION bundle adjustment
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Evaluation of the Anterior Chamber Angle Structures in Perinatal Infants Using a Wide-Field Digital Fundus Camera
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作者 Xian ZHANG Dan-lan LUO +2 位作者 Bo CHEN Qiong-lei ZHONG Hong YANG 《Current Medical Science》 SCIE CAS 2022年第6期1305-1309,共5页
Objective This study aimed to evaluate the ability of a digital fundus camera to observe the development of the anterior chamber angle(ACA)in premature infants.Methods Forty-eight eyes of preterm infants(n=48)were exa... Objective This study aimed to evaluate the ability of a digital fundus camera to observe the development of the anterior chamber angle(ACA)in premature infants.Methods Forty-eight eyes of preterm infants(n=48)were examined by a digital fundus camera to observe the development of the ACA.ACA grading was performed based on the visualization of the anterior chamber structures according to the Scheie Angle Depth Evaluating System.Results ACA images from all 48 infants were successfully acquired using RetCam3.The corrected gestational age ranged from 30 weeks to 49 weeks,which covered the period from 2 months preterm to>2 months post-term.As the corrected gestational age increased,the corrected gestational age grading was significantly decreased.The mean corrected gestational ages of the infants corresponding to the ACA classification from grade IV to grade 0 were 32.75±1.89,37.20±1.30,39.75±2.38,40.56±2.24,and 44.23±2.14 weeks,respectively,which were all significantly different(P<0.05).The regression analysis showed a linear correlation between the grading of the ACA and the corrected gestational age(R2=0.724,P=0.0001).Conclusion The ACA of a full-term newborn can be fully detected and evaluated by a digital fundus camera.For premature infants,part of the ACA is not visible physiologically;however,it should not be misdiagnosed as angle closure or a narrow angle. 展开更多
关键词 digital fundus camera anterior chamber angle GLAUCOMA INFANT
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Enhancement of Frame-rate Using Digital Camera
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作者 LIU Wen-jing HUANG Yao-xiong XIONG Ping 《Semiconductor Photonics and Technology》 CAS 2007年第1期80-82,88,共4页
Frame rate is corresponding to the temporal resolution and the number of the pixels of the picture is corresponding to the spatial resolution. They are both very important for the researchers. The ideal image analysis... Frame rate is corresponding to the temporal resolution and the number of the pixels of the picture is corresponding to the spatial resolution. They are both very important for the researchers. The ideal image analysis and processing system should have high spatiotemporal characteristics, which is much expensive in practical use. A new method to enhance dynamic frame rate using multi-digital camera(DC) is proposed and the result shows that it could increase the frame rate effectively and decreases the cost in practical use. 展开更多
关键词 frame rate temporal resolution digital camera
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Spectral Measurement of Atmospheric Pressure Plasma by Means of Digital Camera
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作者 葛袁静 张广秋 +1 位作者 刘益民 赵志发 《Plasma Science and Technology》 SCIE EI CAS CSCD 2002年第1期1107-1112,共6页
A digital camera measuring system has been used successfully to measure the space fluctuation behaviors of Induced Dielectric Barrier Discharge (IDBD) plasma at atmospheric pres- sure. The experimental results showed ... A digital camera measuring system has been used successfully to measure the space fluctuation behaviors of Induced Dielectric Barrier Discharge (IDBD) plasma at atmospheric pres- sure. The experimental results showed that: (1) The uniformity of electron temperature in space depends on discharge condition and structure of web electrode. For a certain web electrode the higher the discharge voltage is, the more uniform distribution of electron temperature in space will be. For a certain discharge the finer and denser the holes on web electrode are, the more uniform distribution of electron temperature in space will be (2). Digital camera is an available equipment to measure some behaviors of the plasma working at atmospheric pressure. 展开更多
关键词 Spectral Measurement of Atmospheric Pressure Plasma by Means of digital camera
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1分钟,给你的相片做美容——Digital Camera Tools合家欢
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作者 周晶 《数字世界》 2002年第12期70-71,共2页
用数码相机拍得的相片,在保存和网络传输方面有不容置疑的优越性,因此越来越多的人开始使用数码相机。但是我们不得不承认,它在成像质量方面还不能完全替代传统的相机。在你的数码像册里有没有一些太亮、太暗或者有杂点的问题照片呢?不... 用数码相机拍得的相片,在保存和网络传输方面有不容置疑的优越性,因此越来越多的人开始使用数码相机。但是我们不得不承认,它在成像质量方面还不能完全替代传统的相机。在你的数码像册里有没有一些太亮、太暗或者有杂点的问题照片呢?不要以为它们没救了哦,看了今天介绍的方法你就会知道,其实要给它们做美容一点都不难,只要一分钟就可以让你的相片白净又明亮! 咱们要用的这一系列美容工具叫做:Digital camera Tools(本文介绍的软件都可在http://www.mediachance.com/digicam/下载),这些简单又实用的小工具基本上可以解决数码相片中存在的大部分常见问题,比如:偏色、亮度不正常、有杂点等,对传统相片中的类似问题也有一定的作用。每一种工具都有它的适用范围,如果你的照片不在其适用范围之内,或者原本就拍得不错的话,那你可能就看不到太大的差别哦! 展开更多
关键词 相片 digital camera TOOLS 数码相机 调色 去斑
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非常好色 明基BENQ Digital Camera 300mini
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《新潮电子》 2002年第1期20-20,共1页
关键词 明基BENQ digital camera 300mini 数码相机 内存 外形设计
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特工装备 007Digital Camera
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《电脑应用文萃》 2004年第2期25-25,共1页
关键词 数码相机 007 digital camera 光学变焦 数码变焦
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Digital Camera影像视觉牵手搜狐举办中国首届无人机摄影大赛获奖作品选登
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《影像视觉》 2015年第12期12-19,共8页
ANDERS ANDERSSON_海外组一等奖我想一直想用无人机拍这样的自拍照片,于是邀请了我的邻居朋友Tobias在瑞典Ljungby的一个社区摆出这样的姿势。我们在泳池开放时间提前一个小时到达,大概半个小时后完成了拍摄。我也很想在泳池里人多的时... ANDERS ANDERSSON_海外组一等奖我想一直想用无人机拍这样的自拍照片,于是邀请了我的邻居朋友Tobias在瑞典Ljungby的一个社区摆出这样的姿势。我们在泳池开放时间提前一个小时到达,大概半个小时后完成了拍摄。我也很想在泳池里人多的时候拍,但是考虑到会有一定的危险就没有实行。" 展开更多
关键词 digital camera 获奖作品选 影像视觉 里人 摄影大赛 广东省梅州市 繁星点点 花萼楼 大东 大埔县
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高速科学CCD CAMERA系统设计 被引量:20
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作者 张大海 姚大志 +1 位作者 刘伟 吴建文 《光电工程》 EI CAS CSCD 北大核心 2005年第11期87-92,共6页
在实验结果的基础上,介绍了一种高速科学CCD相机系统设计。测试选用了柯达CCD芯片KAF-0401LE和KAF-1001E,用MAXII系列CPLD芯片实现了CCD驱动时序和数据采集时序控制;采用片内集成CDS的CCD信号A/D转换器AD9824进行相关双采样和高速模数转... 在实验结果的基础上,介绍了一种高速科学CCD相机系统设计。测试选用了柯达CCD芯片KAF-0401LE和KAF-1001E,用MAXII系列CPLD芯片实现了CCD驱动时序和数据采集时序控制;采用片内集成CDS的CCD信号A/D转换器AD9824进行相关双采样和高速模数转换;内置8051的CypressUSB2.0控制芯片CY7C68013A完成了高速同步数据传输及与上位机通讯,接收和发送上位机指令等;结合USB采集系统使用VisualC++编写了系统控制界面。实现了采集速率选择(最高10MHzPixelRate对应于20Mbyte/sUSB传输速度)、复合模式选择、单帧/连续采集、制冷温度采集和控制等,适用于同类型CCD相机的系统设计。 展开更多
关键词 ccd相机 CPLD 系统设计 数据采集
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Night Vision Characteristics and Application of MTV 2821CB CCD Camera
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作者 林家明 魏建中 +2 位作者 陈静 郝群 张祥 《Journal of Beijing Institute of Technology》 EI CAS 1999年第4期403-409,共7页
Aim To describe accumulating frames characteristics of CCD camera as a night vision detector. Methods Utilizing CCD external trigger, computer video capture card and image processing software, the image accumul... Aim To describe accumulating frames characteristics of CCD camera as a night vision detector. Methods Utilizing CCD external trigger, computer video capture card and image processing software, the image accumulation was made. Results The detection of the static object image whose illuminance on the CCD FPA(focal plane array) was less than 3 7×10 -5 lx was realized and the image's resolution of 300?TV lines was achieved. Conclusion This experimental system can provide a kind of night vision device capable of detecting the static object at low light level and with low cost compared to an image intensifier. 展开更多
关键词 night vision ccd camera accumulating frames S/N illuminance of ccd FPA
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基于Camera Link总线的CCD高速图像采集技术 被引量:3
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作者 程祖桥 邓辉 +4 位作者 王锋 梁波 季凯帆 王传军 许骏 《天文研究与技术》 CSCD 2011年第4期363-368,共6页
现代天文学研究越来越依赖于高质量的天文观测结果。针对天文实测的需要,对基于Camera Link总线的CCD高速图像采集技术进行了系统调研,分析对比了Camera Link总线技术及其优缺点,对基于Camera link接口的高速CCD采集技术进行了深入的研... 现代天文学研究越来越依赖于高质量的天文观测结果。针对天文实测的需要,对基于Camera Link总线的CCD高速图像采集技术进行了系统调研,分析对比了Camera Link总线技术及其优缺点,对基于Camera link接口的高速CCD采集技术进行了深入的研究,着重讨论了单缓存与双缓存高速采集技术和实现机制。经实际测试,所实现的技术稳定、可靠,CPU负载低,采集速度达到了厂家给出的CCD相机的最高采集速度,可以满足天文大数据量采集与准实时观测的需要。 展开更多
关键词 camera Link总线 ccd 高速图像采集
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基于Camera Link的线阵CCD外同步控制设计与实现 被引量:1
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作者 白士贤 石美红 +1 位作者 姜寿山 宁长胜 《电子测量技术》 2010年第11期77-80,93,共5页
在纺织布匹疵点检测系统中,获取平稳清晰图像对后续布匹图像疵点的精确检测和类别正确识别至关重要。由于布匹疵点检测系统外部事件的不可预测性,如何控制线阵CCD以获取平稳清晰的图像。针对这一问题提出了一种线阵CCD相机外同步控制方... 在纺织布匹疵点检测系统中,获取平稳清晰图像对后续布匹图像疵点的精确检测和类别正确识别至关重要。由于布匹疵点检测系统外部事件的不可预测性,如何控制线阵CCD以获取平稳清晰的图像。针对这一问题提出了一种线阵CCD相机外同步控制方法。该方法采用VHDL语言在Xilinx公司Virtex-II PRO FPGA架构上设计实现。重点介绍了相机自适应的外同步控制设计方案和实现方法,通过ModelSim仿真和布匹疵点检测系统的在线测试,验证了该方法的有效性和可行性。 展开更多
关键词 camera LINK协议 线阵ccd 自适应 现场可编程门阵列 外同步
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基于CCD的激光熔覆熔池平滑度在线监测系统研究
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作者 敖良忠 丁坚 +2 位作者 魏永超 贾文彬 畅浩天 《山西冶金》 CAS 2024年第3期89-92,143,共5页
由于激光熔覆过程高温高亮,无法实时准确判断熔覆效果。使用CCD相机结合平滑度监测算法,对不同功率下的熔池形貌进行监测,验证算法性能,判断熔覆效果,同时尝试叶片修复。结果表明:激光功率过大或者扫描速度过慢,均会导致熔池边缘平滑度... 由于激光熔覆过程高温高亮,无法实时准确判断熔覆效果。使用CCD相机结合平滑度监测算法,对不同功率下的熔池形貌进行监测,验证算法性能,判断熔覆效果,同时尝试叶片修复。结果表明:激光功率过大或者扫描速度过慢,均会导致熔池边缘平滑度较差,进而认为熔覆参数不合适;为防止熔坏基材,可根据监测效果及时停机;发现激光功率与熔池边缘平滑度呈负相关。 展开更多
关键词 激光熔覆 平滑度监测 压气机叶片 ccd相机 熔池
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Improved plasma position detection method in EAST Tokamak using fast CCD camera 被引量:5
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作者 Shuang-Bao Shu Chuan-Mu Yu +3 位作者 Chao Liu Mei-Wen Chen Yu-Zhong Zhang Xin Li 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第2期71-80,共10页
To control the steady-state operation of Tokamak plasma, it is crucial to accurately obtain its shape and position. This paper presents a method for use in rapidly detecting plasma configuration during discharge of th... To control the steady-state operation of Tokamak plasma, it is crucial to accurately obtain its shape and position. This paper presents a method for use in rapidly detecting plasma configuration during discharge of the Experimental Advanced Superconducting Tokamak device. First, a visible/infrared integrated endoscopy diagnostic system with a large field of view is introduced,and the PCO.edge5.5 camera in this system is used to acquire a plasma discharge image. Based on the analysis of various traditional edge detection algorithms, an improved wavelet edge detection algorithm is then introduced to identify the edge of the plasma. In this method, the local maximum of the modulus of wavelet transform is searched along four gradient directions, and the adaptive threshold is adopted. Finally, the detected boundary is fitted using the least square iterative method to accurately obtain the position of the plasma. Experimental results obtained using the EAST device show that the method presented in this paper can realize expected goals and produce ideal effects;this method thus has significant potential for application in further feedback control of plasma. 展开更多
关键词 Experimental Advanced SUPERCONDUCTING TOKAMAK (EAST) Plasma ccd camera EDGE detection
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A Model for Estimating Total Forest Coverage with Ground-Based Digital Photography 被引量:5
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作者 GU Zhu-Jun ZENG Zhi-Yuan +5 位作者 SHI Xue-Zheng LI Lin D. C. WEINDORF ZHA Yong YU Dong-Sheng LIU YongoMei 《Pedosphere》 SCIE CAS CSCD 2010年第3期318-325,共8页
Vegetation fractional coverage (VFC) is one of the key indicators of vegetation distribution. In the work a measurement-based model was developed to derive total forest VFC (TG) as well as the VFC of trees (T) and shr... Vegetation fractional coverage (VFC) is one of the key indicators of vegetation distribution. In the work a measurement-based model was developed to derive total forest VFC (TG) as well as the VFC of trees (T) and shrub-grasses (G) separately in a subtropical forest area in Nanjing, China. Both upward and downward photographs were taken with a digital camera in 72 quadrats (10 m × 10 m each). Fifteen models were established and validated. Models jointly using both T and G performed better than those using the T and G separately. The best model, TG = T + G- 1.134 × T × G- 0.025 (R2 = 0.9115, P < 0.01, root mean squared error = 0.0789), is recommended for application. This model provides a good way to obtain total forest VFC values through taking tree and shrub-grass photos on ground below tree canopy rather than above tree canopy. 展开更多
关键词 digital camera 2-layer photography shrub-grasses trees
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