期刊文献+
共找到4篇文章
< 1 >
每页显示 20 50 100
Clinical application of improved 2D computer-assisted fluoroscopic navigation through simulating a 3D vertebrae image to guide pedicle screw internal fixation
1
作者 刘恩志 《外科研究与新技术》 2011年第2期94-94,共1页
Objective To study the effect of using improved 2D computer-assisted fluoroscopic navigation through simulating 3D vertebrae image to guide pedicle screw internal fixation.Methods Posterior pedicle screw internal fixa... Objective To study the effect of using improved 2D computer-assisted fluoroscopic navigation through simulating 3D vertebrae image to guide pedicle screw internal fixation.Methods Posterior pedicle screw internal fixation,distraction 展开更多
关键词 Clinical application of improved 2D computer-assisted fluoroscopic navigation through simulating a 3D vertebrae image to guide pedicle screw internal fixation
下载PDF
Photoacoustic-enabled automatic vascular navigation:accurate and naked-eye real-time visualization of deep-seated vessels
2
作者 Shu Pan Li Wang +8 位作者 Yuanzheng Ma Guangyu Zhang Rui Liu Tao Zhang Kedi Xiong Siyu Chen Jian Zhang Wende Li Sihua Yang 《Advanced Photonics Nexus》 2023年第4期31-43,共13页
Accurate localization of blood vessels with image navigation is a key element in vascular-related medical research and vascular surgery.However,current vascular navigation techniques cannot provide naked-eye visualiza... Accurate localization of blood vessels with image navigation is a key element in vascular-related medical research and vascular surgery.However,current vascular navigation techniques cannot provide naked-eye visualization of deep vascular information noninvasively and with high resolution,resulting in inaccurate vascular anatomy and diminished surgical success rates.Here,we introduce a photoacousticenabled automatic vascular navigation method combining photoacoustic computed tomography with augmented and mixed reality,for the first time,to our knowledge,enabling accurate and noninvasive visualization of the deep microvascular network within the tissues in real time on a real surgical surface.This approach achieves precise vascular localization accuracy(<0.89 mm)and tiny vascular relocation latency(<1 s)through a zero-mean normalization idea-based visual tracking algorithm and a curved surfacefitting algorithm.Further,the subcutaneous vessels of minimum diameter(∼0.15 mm)in rabbit thigh and the maximum depth(∼7 mm)in human arm can be vividly projected on the skin surface with a computer visionbased projection tracking system to simulate preoperative and intraoperative vascular localization.Thereby,this strategy provides a way to visualize deep vessels without damage on the surgical surface and with precise image navigation,opening an avenue for the application of photoacoustic imaging in surgical operations. 展开更多
关键词 photoacoustic imaging image navigation augmented reality mixed reality vascular localization
下载PDF
FY-4 Meteorological Satellite 被引量:1
3
作者 DONG Yaohai CHEN Xiaojie +4 位作者 CHEN Qiang LYU Wang SHEN Junfeng CHE Lamei JIANG Feng 《Aerospace China》 2017年第2期31-39,共9页
FY-4 is the second generation of Chinese geostationary satellite for quantitative remote sensing meteorological application. The detection efficiency, spectral bands, spatial and time resolution have been greatly impr... FY-4 is the second generation of Chinese geostationary satellite for quantitative remote sensing meteorological application. The detection efficiency, spectral bands, spatial and time resolution have been greatly improved with respect to those of first generation, as well as the radiometric calibration and sensitivity. The combination of multichannel detection and vertical sounding was first realized on FY-4, because both the Advanced Geostationary Radiation Imager(AGRI) and Geostationary Interferometric Infrared Sounder(GIIRS) are on the same spacecraft. The main performance of the payloads including AGRI, GIIRS and Lightning Mapping Imager, and the spacecraft bus are presented, the performance being equivalent to the level of the third generation meteorological satellites in Europe and USA. The acquiring methods of remote sensing data including multichannel and high precision quantitative observing, imaging collection of the ground and cloud, vertical observation of atmospheric temperature and moisture, lightning imaging observation and space environment detection are shown. Several innovative technologies including high accuracy rotation angle detection and scanning control, high precision calibration, micro vibration suppression, unified reference of platform and payload and on-orbit measurement, real-time image navigation and registration on-orbit were applied in FY-4. 展开更多
关键词 FY-4 GEO meteorological satellite three-axis stabilization quantitative remote sensing vertical highspectrum sounding real-time on-board image navigation and registration
下载PDF
Innovations in the Data Processing Algorithm for Chinese FY Meteorological Satellites
4
作者 许健民 郭强 +2 位作者 陆其峰 陆风 张晓虎 《Journal of Meteorological Research》 SCIE 2014年第5期948-964,共17页
This study introduces some innovations in the data processing algorithm for Chinese FY meteorological satellites. Issues about satellite image navigation, radiation calibration, and data assimilation are discussed. A... This study introduces some innovations in the data processing algorithm for Chinese FY meteorological satellites. Issues about satellite image navigation, radiation calibration, and data assimilation are discussed. A time series of the earth's disk center-line count provides information on the orientation of the satellite spin axis. With this information, the altitude parameters of the satellite and then the earth disk location in the south-north direction may be solved. In each spin cycle, the satellite views the sun and the earth. Given the satellite position and altitude, the angle (β) subtended at the satellite by the sun and the earth can be calculated and predicted. Thus, the earth's disk location in the east-west direction is fixed. Based on this principle, we derived an automatic image navigation algorithm for FY2 geosynchronous meteorological satellites with an accuracy approaching pixel level. The FY2 meteorological satellite traveling in a geostationary orbit suffers a large amount of radiation from the sun. The radiation varies on both diurnal and annual scales, which causes radiation responses in the thermal infrared (IR) bands wherein the wavelengths greater than 3.5 μm vibrate periodically on scales of hours to years. These vibrations must be precisely calibrated. First, based on the accurate estimation of the radiant contribution from the front-optics, the variation characteristics of the calibration parameters are obtained on a temporal scale of hours from the space-borne inner-blackbody (IBB) measurement results. Second, the in-orbit measured radiation of the lunar surface is referenced and utilized to correct the sys- tematic bias of the IBB calibration from daily to annual scales. By using such algorithms, we achieved a calibration accuracy of the FY2 satellite's IR imagery of less than 1 K. The on-orbit satellite instrument parameters play an important role in data quality; however, they may be mis-measured due to limitations in the measurement conditions or may be changed due to the space environment after launch. A satellite instrument parameters on-orbit optimizer (SIPOn-Opt) for a polar orbit meteorological satellite was developed to optimize the true state of the instrument parameters on-orbit with regard to the observation constraints. When applying the SIPOn-Opt to FY3 sounding instruments, the FY3 data quality was much improved, compared to its European and the U.S. polar orbit meteorological satellite counterparts, leading to improved forecast skill of numerical weather prediction. 展开更多
关键词 meteorological satellite data processing algorithm image navigation radiation calibration data assimilation
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部