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Modeling and Rectification of Rolling shutter Effect in CMOS Aerial Cameras

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Journal of Harbin Institute of Technology(New Series) 2017年第4期24卷 71-77页

作者： Lei Wan Ye Zhang Ping Jia Jiajia Xu Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of Science Graduate School of the Chinese Academy of Science Key Laboratory of Airborne Optical Imaging and Measurement Chinese Academy of Science

Due to the electronic rolling shutter, high-speed Complementary Metal-Oxide Semiconductor( CMOS) aerial cameras are generally subject to geometric distortions,which cannot be perfectly corrected by conventional vision-based algorithms. In this paper we propose a novel approach to address the problem of rolling shutter distortion in aerial imaging. A mathematical model is established by the coordinate transformation method. It can directly calculate the pixel distortion when an aerial camera is imaging at arbitrary gesture *** all pixel distortions form a distortion map over the whole CMOS array and the map is exploited in the image rectification process incorporating reverse projection. The error analysis indicates that within the margin of measuring errors,the final calculation error of our model is less than 1/2 pixel. The experimental results show that our approach yields good rectification performance in a series of images with different distortions. We demonstrate that our method outperforms other vision-based algorithms in terms of the computational complexity,which makes it more suitable for aerial real-time imaging.

关键词： aerial camera CMOS sensor rolling shutter effect coordinate transformation image rectification

The Design and Experiment Studies of Optical Adapter with Integrated Dust Protection and shutter Design

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Optics and Photonics Journal 2011年第4期1卷 189-196页

作者： Samuel I-En Lin 不详

High power lasers (> +21dBm) have gradually become the common solution for signal transmitting systems including regional cable television, Fiber To The Home (FTTH), and gigabit passive optical networks (G- PONs) due to their ability to generate signals that can be transmitted over long distances. However, if protective design is not implemented in the facility at the client side, users may be exposed to health hazards such as eye damage from these high-power lasers. High-power optical adapters with laser shutter use metal masks to prevent eye exposure to direct laser beams. They have progressively replaced conventional optical adapters and entered the market mainstream. Our study uses the Elastic-Plastic theory together with parametric design to investigate the effect of geometry on the initial spring-back angle of a laser shutter. Once the force stabilizes, the angles of the initial spring back are found to be the same as the simulated results for several attempts. In our study, it is observed that factors including the thickness of the metal masking plate, the initial design angle, the stiffness of the material and the boundary conditions have significant influence on the spring back angle. These can be used as references in design control.

关键词： High Power Leaser Elastic-Plastic Theory Laser shutter Optical Adapter

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免费打电话快门shutter

电脑爱好者(普及版) 2008年第7期 67-68页

作者：牧野龙人

在电脑上利用快门打电话,可以为你节省不少数目可观的电话费。

关键词：邮箱 shutter 号码手机区号国家代码

Time amplifying techniques towards atomic time resolution

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Science China(Technological Sciences) 2009年第12期52卷 3425-3446页

作者： LI JingZhen Institute of Photonic Engineering,College of Electron Science&Technology,Shenzhen University,and Shenzhen Key Laboratory of Micro·Nano Photonic Information,Shenzhen 518060,China Institute of Photonic Engineering College of Electron Science & Technology Shenzhen University and Shenzhen Key Laboratory of Micro-Nano Photonic Information Shenzhen China

High speed imaging technology has opened applications in many fields,such as collision,detonating, high voltage discharge,disintegration and transfer of phonon and exciton in solid,photosynthesis primitive reaction,and electron dynamics inside atom *** principle,all of the transient processes need to be explained theoretically and,at the same time,the time amplifying technique is required for observations of these *** present review concerns the atomic time amplifying mechanism of optical information and the extremely-high speed imaging methods,which are expressed in terms of the short time amplifying *** is well-known that for extremely-high speed imaging with the converter tube,the temporal resolution is in the order of sub-picosecond of the streak imaging,and the imaging frequency is 6×10 8 ―5×10 9 fps(frame per second)of the frame *** the other hand,for the tubeless extremely-high speed imaging,the imaging frequency is 10 7 ―10 14 fps,and its mechanism of forming high speed and framing could involve a lot of factors of the light under investigation,for instance,light speed,light parallelism,the parameters of light wave such as amplitude,phase,polari- zation and wavelength,and even quantum properties of *** the cascaded system of electro- magnetic wave and particle wave,it is possible to simultaneously realize extremely-high resolution in time and space,which is higher than a kite *** it would be possible to break the limit of the Heisenberg uncertainty relation of the optical frequency band.

关键词： time amplification image converter tube imaging tubeless imaging ultra-high speed imaging extremely-high speed imaging holog- raphic coherent shutter optical acceleration

The Suburethral Sling Transobturator Approach for Stress Urinary Incontinence Treatment in Women in the Maternity and Neonatology Center of Tunis (WTSC)

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Open Journal of Obstetrics and Gynecology 2017年第1期7卷 80-85页

作者： Moufalilou Aboubakar Veronique Tognifode Justin Denakpo Faouzia Zouari Centre Hospitalier Universitaire de la Mère et de l’Enfant (CHU-MEL) Cotonou Benin Faculté à Caractère Spécial de Formation Médicale Université de Porto Novo Porto Novo Benin Centre de Maternité et de Néonatologie de Tunis Service C Gynécologie-Obstétrique Tunis Tunisia

The authors, through a descriptive retrospective study have evaluated the results of surgical treatment, by Tension-Free Obturator tape (TOT) technique, of urinary incontinence in the first 68 patients operated in the Department “C” of Obstetrics and Gynecology of the Maternity and Neonatology Centre of Tunis (WTSC). The average age in those patients was 55.14 ± 8.47 years with extremes of 40 and 82 years. The majority of the patients (72%) were under the age of 60 years. In sixty-one patients (89%), no urine leak has been detected and they were healed. In three patients (4%) there was improvement with partial recovery. Three other (4%) did not notice any improvement after the surgery. No case of dysuria or rejection of the strip has been reported. It was concluded that the declared satisfaction rate is 93%.

关键词： Urinary Incontinence Stress shutter Sling TOT

Morphotectonic Study of Frontal Siwalik Hills, near Gandhiri, Kangra, Himachal Pradesh, India

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Open Journal of Geology 2020年第4期10卷 280-300页

作者： Yoginder Singh A. R. Chaudhri Department of Geology Kurukshetra University Kurukshetra India

The densely populated foothill zone of western Himalaya between the Beas river and the Chakki stream in and around Kangra is being critically examined by us considering the seismo-tectonic destructive potential of the 1905 (Mw 7.8) Kangra earthquake which has not been evaluated so far. We use Resourcesat 1: LISS III Ortho satellite imageries and field studies to qualitatively and quantitatively assess the active tectonic setup of the terrain. Quantitative morphotectonic analysis viz. hypsometric integral, drainage basin asymmetry, stream sinuosity index, ratio of valley floor width to valley height, stream length gradient index, basin shape index and mountain front sinuosity index are being evaluated on high resolution digital elevation model. The five sub-drainage basins of the Gandhiri stream, the Sukar stream and the Duhg stream of Kangra district of Himachal Pradesh, India are being morphotectonically analyzed. The value of hypsometric integral, drainage basin asymmetry, stream sinuosity index, ratio of valley floor width to valley height, stream length gradient index, basin shape index and mountain front sinuosity index reveal that the terrain is tectonically active. An active dextral strike slip fault with significant oblique slip component has been inferred and is being named as the Gandhiri Fault. This fault crosses all the five sub-drainage basins and results in multiple stream offsets. The Index of Relative Tectonic Activity (IRAT) has been established for different sub-drainage basins. The study reveals that the terrain near Gandhiri in Kangra district of Himachal Pradesh is seismo-tectonically active and proper building codes should be followed in construction activity.

关键词： Morphotectonic shutter Ridges Gandhiri Fault Index of Relative Tectonic Activity (IRAT)

Evaluation of Sample Taxicab Security Cameras

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Journal of Transportation Technologies 2017年第4期7卷 390-422页

作者： Shengke Zeng Harlan E. Amandus Alfred A. Amendola Richard S. Current Bradley H. Newbraugh Douglas M. Cantis Darlene Weaver Division of Safety Research National Institute for Occupational Safety and Health Morgantown WV USA

Background: Taxicab drivers have high homicide rates compared to all worker occupations. To help taxi fleets select effective taxicab security cameras, this project tested eight sample taxicab security cameras for determining their photographic quality which correlated to the effectiveness of in-taxicab facial identification. Methods: Five photographic quality metric thresholds: 1) resolution, 2) highlight dynamic range, 3) shadow dynamic range, 4) lens distortion, and 5) shutter speed, were employed to evaluate the photographic quality of the sample cameras. Waterproof tests and fire-resistive tests on recording memory cards were conducted to determine the memory card survivability in water and simulated fire. Results: The Full-HD (1920 × 1080 pixels), HD (1280 × 720 pixels) and dual-lens VGA (2 × 640 × 480 pixels with wide-angle and telephoto lenses) cameras performed well in resolution tests in daylight conditions. The resolution of a single-lens VGA (640 × 480 pixels) camera did not meet the resolution minimum requirements. All of the recording memory cards passed the five-meter/72-hour waterproof test. A fire resistant chamber made with one fire insulation material could protect a single memory card at 538°C/1000°F for a five-minute simulated fire test. Conclusions: Single-lens VGA-resolution (640 × 480 pixels) cameras are not suggested for use as security cameras in taxicabs with two or more rows of seats. The recording memory cards can survive 5-meter/72-hour waterproof tests. The memory card chamber built with an existing heat insulation material can protect an individual memory card during 538°C?(1000°F)/5-minute fire resistance oven-test.

关键词： Taxicab Homicide Facial Identification Taxicab Security Camera Tests Resolution Dynamic Range Lens Distortion shutter Speed Recording Media Protection

Abbott architect i2000SR故障检修

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医疗装备 2012年第6期25卷 85-86页

作者：丁其浪浙江省天台县人民医院设备科浙江天台317200

本文介绍了Architect i2000SR全自动免疫分析仪3例故障的处理方法及维修总结。

关键词：雅培 I2000SR Reader shutter 缓冲液温度传感器