Background To report quality control methods and baseline reproducibility data of the ultrasound measurements of carotid artery intima-media thickness in the project of Establishment of an Integrated System for Corona...Background To report quality control methods and baseline reproducibility data of the ultrasound measurements of carotid artery intima-media thickness in the project of Establishment of an Integrated System for Coronary Heart Disease Prevention and Treatment. Methods Standard ultrasound scanning and measuring protocols were established by the study group. All sonographers and readers were trained by the carotid ultrasound core lab and all digital ultrasound images were centrally read. Ten subjects were scanned twice （with 1 week interval） by 2 sonographers independently and images were read by a single reader to evaluate the sonographer variability. Twenty subjects＇ images were read twice （with 1 week interval） by a single reader to assess the reader variability and the reproducibility of IMT measured at different carotid segments. Results The intraclass correlation （ICC） of intra- and inter-sonographer and intra- reader for mean IMT measurements was 0.99, 0.98 and 0.97 respectively; while for max IMT, it was 0.97, 0.99 and 0.95 respectively. Among different carotid segments and sites, ICC for mean 1MT measurements of common carotid （CCA）, carotid artery bulb （Bulb）, internal carotid artery （ICA）, overall near wall and overall far wall was 0.97, 0.99, 0.89, 0.93 and 0.98 respectively. Conclusion The reproducibility of IMT measurements according to our protocol is acceptable, although better reproducibility is found when measuring the mean IMT than max IMT, CCA and Bulb IMT than ICA IMT, and far wall IMT than near wall IMT.展开更多
The conventional quality control method of core rocldill dam construction exhibit difficulty controlling compaction parameters accurately or ensuring construction quality. This is because it is easily influenced by hu...The conventional quality control method of core rocldill dam construction exhibit difficulty controlling compaction parameters accurately or ensuring construction quality. This is because it is easily influenced by human behavior or lack of adequate management. We therefore establish the timely monitoring indexes and control criteria of compaction processes by considering the characteristics and quality requirements of high core rockffll dam construction. Based on the established indexes and criteria, integrating GPS, GPRS and PDA technologies, a real-time compaction quality monitoring method is proposed. The relevant key techniques are proposed as well, including automatic collection of information and a graphic algorithm for rolling-process visualization. By the proposed method and techniques, a real-time monitoring system is provided to realize the precise automatic online entire-process monitoring of compaction parameters, including compaction pass, rolling trajectory, nmning speed of roller, vibration status and rolled pavement thickness. The application of the Nuozhadu project shows that the proposed system can control compaction parameters effectively and ensure better construction quality. Therefore, it might become a new way towards construction quality control of high core rockfill dam.展开更多
文摘Background To report quality control methods and baseline reproducibility data of the ultrasound measurements of carotid artery intima-media thickness in the project of Establishment of an Integrated System for Coronary Heart Disease Prevention and Treatment. Methods Standard ultrasound scanning and measuring protocols were established by the study group. All sonographers and readers were trained by the carotid ultrasound core lab and all digital ultrasound images were centrally read. Ten subjects were scanned twice （with 1 week interval） by 2 sonographers independently and images were read by a single reader to evaluate the sonographer variability. Twenty subjects＇ images were read twice （with 1 week interval） by a single reader to assess the reader variability and the reproducibility of IMT measured at different carotid segments. Results The intraclass correlation （ICC） of intra- and inter-sonographer and intra- reader for mean IMT measurements was 0.99, 0.98 and 0.97 respectively; while for max IMT, it was 0.97, 0.99 and 0.95 respectively. Among different carotid segments and sites, ICC for mean 1MT measurements of common carotid （CCA）, carotid artery bulb （Bulb）, internal carotid artery （ICA）, overall near wall and overall far wall was 0.97, 0.99, 0.89, 0.93 and 0.98 respectively. Conclusion The reproducibility of IMT measurements according to our protocol is acceptable, although better reproducibility is found when measuring the mean IMT than max IMT, CCA and Bulb IMT than ICA IMT, and far wall IMT than near wall IMT.
基金supported by the National Natural Science Foundation of China (Grant Nos. 51021004, 51079096)the Program for New Century Excellent Talents in University (Grant No. NCET-08-0391)
文摘The conventional quality control method of core rocldill dam construction exhibit difficulty controlling compaction parameters accurately or ensuring construction quality. This is because it is easily influenced by human behavior or lack of adequate management. We therefore establish the timely monitoring indexes and control criteria of compaction processes by considering the characteristics and quality requirements of high core rockffll dam construction. Based on the established indexes and criteria, integrating GPS, GPRS and PDA technologies, a real-time compaction quality monitoring method is proposed. The relevant key techniques are proposed as well, including automatic collection of information and a graphic algorithm for rolling-process visualization. By the proposed method and techniques, a real-time monitoring system is provided to realize the precise automatic online entire-process monitoring of compaction parameters, including compaction pass, rolling trajectory, nmning speed of roller, vibration status and rolled pavement thickness. The application of the Nuozhadu project shows that the proposed system can control compaction parameters effectively and ensure better construction quality. Therefore, it might become a new way towards construction quality control of high core rockfill dam.
