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Optical diagnosis of colorectal polyps using high-definition i-scan: An educational experience
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作者 Mariёlle WE Bouwens Rogier de Ridder +4 位作者 Ad AM Masclee Ann Driessen Robert G Riedl Bjorn Winkens Silvia Sanduleanu 《World Journal of Gastroenterology》 SCIE CAS 2013年第27期4334-4343,共10页
AIM:To examine performances regarding prediction of polyp histology using high-definition (HD) i-scan in a group of endoscopists with varying levels of experience. METHODS:We used a digital library of HD i-scan still ... AIM:To examine performances regarding prediction of polyp histology using high-definition (HD) i-scan in a group of endoscopists with varying levels of experience. METHODS:We used a digital library of HD i-scan still images, comprising twin pictures (surface enhancement and tone enhancement), collected at our university hospital. We defined endoscopic features of adenomatous and non-adenomatous polyps, according to the following parameters:color, surface pattern and vascular pattern. We familiarized the participating endoscopists on optical diagnosis of colorectal polyps using a 20-min didactic training session. All endoscopists were asked to evaluate an image set of 50 colorectal polyps with regard to polyp histology. We classified the diagnoses into high confidence (i.e., cases in which the endoscopist could assign a diagnosis with certainty) and low confidence diagnoses (i.e., cases in which the endoscopist preferred to send the polyp for formal histology). Mean sensitivity, specificity and accuracy per endoscopist/image were computed and differences between groups tested using independent-samples t tests. High vs low confidence diagnoses were compared using the pairedsamples t test. RESULTS:Eleven endoscopists without previous experience on optical diagnosis evaluated a total of 550 images (396 adenomatous, 154 non-adenomatous). Mean sensitivity, specificity and accuracy for diagnosing adenomas were 79.3%, 85.7% and 81.1%, respectively. No significant differences were found between gastroenterologists and trainees regarding performances of optical diagnosis (mean accuracy 78.0%vs 82.9%,P = 0.098). Diminutive lesions were predicted with a lower mean accuracy as compared to non-diminutive lesions (74.2% vs 93.1%, P = 0.008). A total of 446 (81.1%) diagnoses were made with high confidence. High confidence diagnoses corresponded to a significantly higher mean accuracy than low confidence diagnoses (84.0% vs 64.3%, P = 0.008). A total of 319 (58.0%) images were evaluated as having excellent quality. Considering excellent quality images in conjunction with high confidence diagnosis, overall accuracy increased to 92.8%. CONCLUSION:After a single training session, endoscopists with varying levels of experience can already provide optical diagnosis with an accuracy of 84.0%. 展开更多
关键词 COLONOSCOPY high-definition i-scan Optical diagnosis Colorectal POLYPS Training
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A Reliable Adaptive High-Definition Transmission System for Distance Learning
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作者 徐奇 李鹤廷 《Journal of Shanghai Jiaotong university(Science)》 EI 2007年第6期740-743,共4页
There is an increasing demand for supporting high-quality real-time audiovisual services for the next generation wired and wireless networks. However, due to variety of bandwidths of different networks, it is a great ... There is an increasing demand for supporting high-quality real-time audiovisual services for the next generation wired and wireless networks. However, due to variety of bandwidths of different networks, it is a great challenge for deployment. In this paper, a novel high-definition (HD) video transmission system was proposed which depends upon reliable compound multicast protocols and QoS control over the various kinds of networks. This system detects client's network condition and assigns it to a proper proxy. Each proxy is capable of detecting network parameters and adaptively tuning such transport parameters as bit rate, video resolution, frame rate and QoS mechanisms to this condition. It also provides FEC error recovery under consideration of characteristics of MPEG4 video codec. Our simulation demonstrates that different network clients such as ADSL, CERNET, and CERNET2 can receive more video reliability with less delay. 展开更多
关键词 ADAPTIVE high-definition(HD) transmission system distance learning RELIABLE compound MULTICAST protocol (RCMP)
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Wavelet Transform-Based High-Definition Map Construction From a Panoramic Camera 被引量:1
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作者 庄瀚洋 周学军 +1 位作者 王春香 钱宇晗 《Journal of Shanghai Jiaotong university(Science)》 EI 2021年第5期569-576,共8页
High-definition(HD)maps are key components that provide rich topologic and semantic information for decision-making in vehicle autonomous driving systems.A complete ground orthophoto is usually used as the base image ... High-definition(HD)maps are key components that provide rich topologic and semantic information for decision-making in vehicle autonomous driving systems.A complete ground orthophoto is usually used as the base image to construct the HD map.The ground orthophoto is obtained through inverse perspective transformation and image mosaicing.During the image mosaicing,multiple consecutive orthophotos are stitched together using pose information and image registration.In this study,wavelet transform is introduced to the image mosaicing process to alleviate the information loss caused by image overlapping.In the orthophoto wavelet transform,high-frequency and low-frequency components are fused using different strategies to form a complete base image with clearer local details.Experimental results show that the accuracy of the orthophotos generated using this method is improved. 展开更多
关键词 high-definition(HD)map wavelet transform image registration PANORAMA
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Precision in detecting colon lesions:A key to effective screening policy but will it improve overall outcomes?
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作者 Luis Ramon Rabago Maria Delgado Galan 《World Journal of Gastrointestinal Endoscopy》 2024年第3期102-107,共6页
Colonoscopy is the gold standard for the screening and diagnosis of colorectal cancer,resulting in a decrease in the incidence and mortality of colon cancer.However,it has a 21%rate of missed polyps.Several strategies... Colonoscopy is the gold standard for the screening and diagnosis of colorectal cancer,resulting in a decrease in the incidence and mortality of colon cancer.However,it has a 21%rate of missed polyps.Several strategies have been devised to increase polyp detection rates and improve their characterization and delimi-tation.These include chromoendoscopy(CE),the use of other devices such as Endo cuffs,and major advances in endoscopic equipment[high definition,magnification,narrow band imaging,i-scan,flexible spectral imaging color enhancement,texture and color enhancement imaging(TXI),etc.].In the retrospective study by Hiramatsu et al,they compared white-light imaging with CE,TXI,and CE+TXI to determine which of these strategies allows for better definition and delimitation of polyps.They concluded that employing CE associated with TXI stands out as the most effective method to utilize.It remains to be demonstrated whether these results are extrapolatable to other types of virtual CE.Additionally,further investigation is needed in order to ascertain whether this strategy could lead to a reduction in the recurrence of excised lesions and potentially lower the occurrence of interval cancer. 展开更多
关键词 Colonoscopy screening Interval colorectal cancer Post colonoscopy colorectal cancer CHROMOENDOSCOPY Virtual chromoendoscopy high-definition whitelight endoscopy Texture and color enhancement imaging Indigo carmine ADENOMA Sessile serrated lesion
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Automatic Lane-Level Intersection Map Generation using Low-Channel Roadside LiDAR
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作者 Hui Liu Ciyun Lin +1 位作者 Bowen Gong Dayong Wu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第5期1209-1222,共14页
A lane-level intersection map is a cornerstone in high-definition(HD) traffic network maps for autonomous driving and high-precision intelligent transportation systems applications such as traffic management and contr... A lane-level intersection map is a cornerstone in high-definition(HD) traffic network maps for autonomous driving and high-precision intelligent transportation systems applications such as traffic management and control, and traffic accident evaluation and prevention. Mapping an HD intersection is time-consuming, labor-intensive, and expensive with conventional methods. In this paper, we used a low-channel roadside light detection and range sensor(LiDAR) to automatically and dynamically generate a lane-level intersection, including the signal phases, geometry, layout, and lane directions. First, a mathematical model was proposed to describe the topology and detail of a lane-level intersection. Second, continuous and discontinuous traffic object trajectories were extracted to identify the signal phases and times. Third, the layout, geometry, and lane direction were identified using the convex hull detection algorithm for trajectories. Fourth, a sliding window algorithm was presented to detect the lane marking and extract the lane, and the virtual lane connecting the inbound and outbound of the intersection were generated using the vehicle trajectories within the intersection and considering the traffic rules. In the field experiment, the mean absolute estimation error is 2 s for signal phase and time identification. The lane marking identification Precision and Recall are96% and 94.12%, respectively. Compared with the satellite-based,MMS-based, and crowdsourcing-based lane mapping methods,the average lane location deviation is 0.2 m and the update period is less than one hour by the proposed method with low-channel roadside LiDAR. 展开更多
关键词 high-definition map lane-level intersection map roadside LiDAR sliding window traffic object trajectory
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Progress on CASEarth Satellite Development 被引量:3
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作者 GUO Huadong CHEN Hongyu +1 位作者 CHEN Liangfu FU Bihong 《空间科学学报》 CAS CSCD 北大核心 2020年第5期707-717,共11页
CASEarth satellite is the first space Earth science satellite produced by the Chinese Academy of Sciences.The satellite has three payloads:high-definition Thermal Infrared Spectrometer(TIS),highdefinition Glimmer Imag... CASEarth satellite is the first space Earth science satellite produced by the Chinese Academy of Sciences.The satellite has three payloads:high-definition Thermal Infrared Spectrometer(TIS),highdefinition Glimmer Imager for Urbanization(GIU),and high-definition Multispectral Imager for Inshore(MII).These payloads are used to explore the urbanization level and residential layout,the coastal ecosystem,and new methods and approaches of environmental detection during night-time and even under conditions of polar aurora and provide scientific evidence for the refined depiction of human traces.The CASEarth satellite can provide space observation data for A Project on Big Earth Data Science Engineering as well as scientific and application studies inside and outside China. 展开更多
关键词 CASEarth satellite Human traces Thermal infrared spectrometer high-definition glimmer imager for urbanization Multispectral imager for inshore
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Dimension-Enhanced Ultra-High Performance Liquid Chromatography/Ion Mobility-Quadrupole Time-of-Flight Mass Spectrometry Combined with Intelligent Peak Annotation for the Rapid Characterization of the Multiple Components from Seeds of Descurainia sophia 被引量:1
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作者 Simiao Wang Xue Li +7 位作者 Boxue Chen Shitong Li Jiali Wang Jing Wang Mingshuo Yang Xiaoyan Xu Hongda Wang Wenzhi Yang 《Phyton-International Journal of Experimental Botany》 SCIE 2022年第3期541-567,共27页
The complex composition of herbal metabolites necessitates the development of powerful analytical techniques aimed to identify the bioactive components.The seeds of Descurainia sophia(SDS)are utilized in China as a co... The complex composition of herbal metabolites necessitates the development of powerful analytical techniques aimed to identify the bioactive components.The seeds of Descurainia sophia(SDS)are utilized in China as a cough and asthma relieving agent.Herein,a dimension-enhanced integral approach,by combining ultra-high performance liquid chromatography/ion mobility-quadrupole time-of-flight mass spectrometry(UHPLC/IMQTOF-MS)and intelligent peak annotation,was developed to rapidly characterize the multicomponents from SDS.Good chromatographic separation was achieved within 38 min on a UPLC CSH C18(2.1×100 mm,1.7μm)column which was eluted by 0.1%formic acid in water(water phase)and acetonitrile(organic phase).Collision-induced dissociation-MS^(2)data were acquired by the data-independent high-definition MS^(E)(HDMS^(E))in both the negative and positive electrospray ionization modes.A major components knockout strategy was applied to improve the characterization of those minor ingredients by enhancing the injection volume.Moreover,a self-built chemistry library was established,which could be matched by the UNIFI software enabling automatic peak annotation of the obtained HDMS^(E)data.As a result of applying the intelligent peak annotation workflows and further confirmation process,a total of 53 compounds were identified or tentatively characterized from the SDS,including 29 flavonoids,one uridine derivative,four glucosides,one lignin,one phenolic compound,and 17 others.Notably,four-dimensional information related to the structure(e.g.,retention time,collision cross section,MS^(1)and MS^(2)data)was obtained for each component by the developed integral approach,and the results would greatly benefit the quality control of SDS. 展开更多
关键词 Descurainia sophia multicomponent characterization ultra-high performance liquid chromatography ion mobility/quadrupole time-of-flight mass spectrometry high-definition MS^(E) flavonoid
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Feasibility of Transabdominal Real-time CDFI and HDFI Techniques for Fetal Pulmonary Vein Display in the First Trimester
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作者 Dong-mei LIN Yun-xiao ZHU +4 位作者 Ying TAN Yu-jun HUANG Kun YUAN Wen-fen LIU Zuo-feng XU 《Current Medical Science》 SCIE CAS 2022年第3期635-641,共7页
Objective This study aimed to assess the feasibility and usefulness of transabdominal color Doppler flow imaging(CDFI)technology and the high-definition flow imaging(HDFI)technique in detecting fetal pulmonary veins(P... Objective This study aimed to assess the feasibility and usefulness of transabdominal color Doppler flow imaging(CDFI)technology and the high-definition flow imaging(HDFI)technique in detecting fetal pulmonary veins(PVs)in the first trimester(11–13^(+6)weeks).Methods From December 2018 to October 2019,328 pregnant women with 328 normal singleton fetuses(crown-rump length:45–84 mm)who had undergone CDFI and HDFI scans for fetal heart and vessel examination were enrolled in this study.The cases were divided into three groups according to the gestational age:group A,11^(+0)−11^(+6)weeks;group B,12^(+0)−12^(+6)weeks;and group C,13^(+0)−13^(+6)weeks.Baseline sonograms and CDFI and HDFI images were analyzed by two senior radiologists independently and blindly.The abilities of CDFI and HDFI to display PVs were compared.Results Successful PV display rates via CDFI and HDFI were 2.3%and 68.2%(P<0.01),22.4%and 82.4%(P<0.01),41.5%and 91.2%(P<0.01)for group A,group B,and group C,respectively.The total successful display rates for the two methods were 28.9%(CDFI)and 84.8%(HDFI)(P<0.01).Conclusions The HDFI technique is more valuable than CDFI for detecting PVs in early pregnancy(11–13^(+6)weeks).HDFI can detect at least one PV in all cases and may be used to detect pulmonary venous anomalies early. 展开更多
关键词 pulmonary vein first trimester prenatal sonography high-definition flow imaging color Doppler flow imaging
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A320系列飞机新型娱乐系统的维护和故障处理
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作者 杨欢 《科学技术创新》 2020年第30期108-109,共2页
飞机的娱乐系统主要功能是向旅客提供重要信息提醒和娱乐影视服务,如果出现故障,则需要乘务员进行信息提醒并降低旅客的乘机娱乐体验。新型娱乐系统由于维修手册中的信息较少,因而对维护和故障不能及时有效的处理。
关键词 飞机娱乐系统 HDMS(high-definition Media Server) 故障处理
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Lane Detection:A Survey with New Results 被引量:2
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作者 Dun Liang Yuan-Chen Guo +2 位作者 Shao-Kui Zhang Tai-Jiang Mu Xiaolei Huang 《Journal of Computer Science & Technology》 SCIE EI CSCD 2020年第3期493-505,共13页
Lane detection is essential for many aspects of autonomous driving,such as lane-based navigation and high-definition(HD)map modeling.Although lane detection is challenging especially with complex road conditions,consi... Lane detection is essential for many aspects of autonomous driving,such as lane-based navigation and high-definition(HD)map modeling.Although lane detection is challenging especially with complex road conditions,considerable progress has been witnessed in this area in the past several years.In this survey,we review recent visual-based lane detection datasets and methods.For datasets,we categorize them by annotations,provide detailed descriptions for each category,and show comparisons among them.For methods,we focus on methods based on deep learning and organize them in terms of their detection targets.Moreover,we introduce a new dataset with more detailed annotations for HD map modeling,a new direction for lane detection that is applicable to autonomous driving in complex road conditions,a deep neural network LineNet for lane detection,and show its application to HD map modeling. 展开更多
关键词 convolutional neural network(CNN) DATASET deep learning high-definition(HD)map lane detection
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Analysis of Phytochemical Constituents of Zuogui Wan in Rat Serum and its Effects on Early Embryonic Development of Mice 被引量:1
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作者 Ya-Fei Guo Kai-Xia Xu +4 位作者 Jie-Wei Hong Shuang Yin Xin Niu Qian-Jin Feng Ying-Li Wang 《World Journal of Traditional Chinese Medicine》 2020年第3期324-330,共7页
Objective:Zuogui Wan(ZGW)has been used as a typical prescription for tonifying kidney essence in traditional Chinese medicine.The objective of this study is to elucidate the phytochemical constituents of ZGW-treated r... Objective:Zuogui Wan(ZGW)has been used as a typical prescription for tonifying kidney essence in traditional Chinese medicine.The objective of this study is to elucidate the phytochemical constituents of ZGW-treated rat serum(ZGWRS)using ultra-performance liquid chromatography-electrospray ionization/quadrupole-time-of-flight high-definition mass spectrometry(UPLC-ESI-Q-TOF-MS).Methods:ZGW was administered to rats,and the phytochemical constituents in rat serum were determined using UPLC-ESI-Q-TOF-MS.MetaboLynx analysis in negative ion mode was adopted to characterize the chemical constituents of ZGWRS.Orthogonal partial least squares discriminant analysis was applied for the discovery of constituents of ZGW that entered the serum of rats.The fertilized eggs collected from the same experiment were randomly divided into four groups,including the normal,40 mmol/L glucose,40 mmol/L glucose 5%control rat serum,and 40 mmol/L glucose 5%ZGWRS groups.They were cultivated at 37°C and 5%CO2 in a saturated humidity CO2 incubator.The blastocyst rate and two-cell rate were used to evaluate the effects of ZGWRS on embryonic development.Results:Thirteen constituents were identified in the ZGWRS,among which sweroside,loganin,morroniside,loganic acid,and 8-epiloganic acid were from Fructus Corni(Shan Zhu Yu).5-Hydroxymethyl-2-furfural-glucuronide,2-H-5-hydroxymethyl-2-furfural-glucuronide,3-hydroxy-2,6,6-trimethyl-1-cyclohexene-1-carboxylic acid,andβ-D-ribofuranuronic acid methyl ester triacetate were from Radix Rehmanniae Preparata(Shu Di Huang).Coumaric acid was from Fructus Lycii(Gou Qi Zi).Kaempferol-3-beta-O-glucuronide and cuscutamine were from Semen Cuscutae(Tu Si Zi).The embryonic development was significantly inhibited using 40 mmol/L glucose.Compared with the normal group,the blastocyst rate of the glucose group was decreased.The blastocyst rate of the 40 mmol/L glucose 5%ZGWRS group was significantly higher than that of the glucose group,indicating that ZGWRS negates the effect of glucose on mouse embryonic development.Conclusion:The results verified that a rapid and robust UPLC-ESI-Q-TOF-MS-based platform had been successful for identifying multiple constituents of ZGW.ZGWRS is rich in active constituents of iridoid glycosides.The results of this study also showed that ZGWRS could negate the effect of glucose on mouse embryonic development. 展开更多
关键词 Orthogonal partial least squared discriminant analysis ultra-performance liquid chromatograph-electrospray ionization/quadrupole-time-of-flight high-definition mass spectrometry Zuogui Wan
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An efficient hardware design for HDTV H.264/AVC encoder
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作者 Liang WEI 《Journal of Zhejiang University-Science C(Computers and Electronics)》 SCIE EI 2011年第6期499-506,共8页
This paper presents a hardware efficient high definition television (HDTV) encoder for H.264/AVC. We use a two-level mode decision (MD) mechanism to reduce the complexity and maintain the performance, and design a sha... This paper presents a hardware efficient high definition television (HDTV) encoder for H.264/AVC. We use a two-level mode decision (MD) mechanism to reduce the complexity and maintain the performance, and design a sharable architecture for normal mode fractional motion estimation (NFME), special mode fractional motion estimation (SFME), and luma motion compensation (LMC), to decrease the hardware cost. Based on these technologies, we adopt a four-stage macro-block pipeline scheme using an efficient memory management strategy for the system, which greatly reduces on-chip memory and bandwidth requirements. The proposed encoder uses about 1126k gates with an average Bjontegaard-Delta peak signal-to-noise ratio (BD-PSNR) decrease of 0.5 dB, compared with JM15.0. It can fully satisfy the real-time video encoding for 1080p@30 frames/s of H.264/AVC high profile. 展开更多
关键词 H.264/AVC high-definition television (HDTV) HARDWARE ARCHITECTURE ENCODER
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