A fast local reference frame(LRF)construction method based on the signed surface variation is proposed,which can adapt to the real-time applications such as self-driving,face recognition,object detection.The z-axis of...A fast local reference frame(LRF)construction method based on the signed surface variation is proposed,which can adapt to the real-time applications such as self-driving,face recognition,object detection.The z-axis of the LRF is generated based on the concavity of the local surface of keypoint.The x-axis is constructed by the weighted vector sum of a set of projection vectors of the local neighborhoods around keypoint.The performance of the proposed LRF is evaluated on six standard datasets and compared with six state-of-the-art LRF construction methods(e.g.,BOARD,FLARE,SHOT,RoPS and TOLDI).Experimental results validate the high repeatability,robustness,universality and time efficiency of our method.展开更多
Wanshan area has been chosen to be the specified field to calibrate and validate(Cal/Val)the HY-2 altimeter and its follow-on satellites.In March 2018,an experiment has been conducted to determine the sea surface heig...Wanshan area has been chosen to be the specified field to calibrate and validate(Cal/Val)the HY-2 altimeter and its follow-on satellites.In March 2018,an experiment has been conducted to determine the sea surface height(SSH)under the HY-2 A ground track(Pass No.203).A GPS towing-body(GPS-TB)was designed to measure the SSH covering an area of about 6 km×28 km wide centered on the HY-2 A altimeter satellite ground track.Three GPS reference stations,one tide gauge and a GPS buoy were placed in the research area,in order to process and resolve the kinematic solution and check the precision of the GPS-TB respectively.All the GPS data were calculated by the GAMIT/GLOBK software and TRACK module.The sea surface was determined by the GPS-TB solution and the tide gauge placed on Zhiwan Island.Then the sea surface of this area was interpolated by Arc GIS10.2 with ordinary Kriging method.The results showed that the precision of the GPS-TB is about 1.10 cm compared with the tide gauge placed nearby,which has an equivalent precision with the GPS buoy.The interpolated sea surface has a bias of–1.5–4.0 cm with standard deviation of 0.2–2.4 cm compared with the checking line.The gradient of the measured sea surface is about 1.62 cm/km along the HY-2 orbit which shows a good agreement compared with the CLS11 mean sea surface(MSS).In the Cal/Val of satellites,the sea surface between the tide gauge/GPS buoy and the footprint of altimeter can be improved by this work.展开更多
Our study aims to determine diagnostic reference levels (DRL) for chest front examination in postero anterior (PA) for optimizing patient entrance surface dose (ESD) and dose-area product (DAP) of patients in west of ...Our study aims to determine diagnostic reference levels (DRL) for chest front examination in postero anterior (PA) for optimizing patient entrance surface dose (ESD) and dose-area product (DAP) of patients in west of Côte d’Ivoire. 90 patients from three hospitals undergoing conventional radiology were considered. The ESD and DAP for each patient were obtained during chest radiography (PA) examination. The measurements were performed with the device call Dose-Area Product-meter (DAP-meter) with brand Diamentor M4-KDK, type 11017. The DRL were obtained in applying the 75th percentile statistical method to the obtained ESD and DAP. The obtained DRL in ESD for chest radiography for all rooms is 0.40 mGy and in DAP is 54.85 cGy·cm2. Our DRL for ESD is higher than those obtained in Abidjan District and in other countries like UK and Cameroon. Our DRL for DAP is higher than those from Abidjan and all other countries for which a similar study was made. The comparison of these values to those from Abidjan and other countries, shows us that radiology technicians can make efforts to choose radiological parameters to reduce ESD. They must use convenable the X-rays tube to reduce DAP by reducing the patient exposure surface.展开更多
A globally accurate potential energy surface is reported for the electronic ground-state H2O＋. The ab initio energies utilized to map the potential energy surface are calculated at the multireference configuration in...A globally accurate potential energy surface is reported for the electronic ground-state H2O＋. The ab initio energies utilized to map the potential energy surface are calculated at the multireference configuration interaction method employing the aug-cc-pVQZ basis set and the full valence complete active space wave function as reference. In order to improve accu- racy of the resulting raw ab initio energies, they are then extrapolated to the complete basis set limit and most importantly to the full configuration-interaction limit by semiempirically correcting the dynamical correlation using the double many- body expansion-scaled external correlation method. The topographical features of the current potential energy surface were examined in detail, which agree nicely with those of other theoretical work.展开更多
基金Youth Program of National Natural Science Foundation of China(Nos.41901415,61801481)。
文摘A fast local reference frame(LRF)construction method based on the signed surface variation is proposed,which can adapt to the real-time applications such as self-driving,face recognition,object detection.The z-axis of the LRF is generated based on the concavity of the local surface of keypoint.The x-axis is constructed by the weighted vector sum of a set of projection vectors of the local neighborhoods around keypoint.The performance of the proposed LRF is evaluated on six standard datasets and compared with six state-of-the-art LRF construction methods(e.g.,BOARD,FLARE,SHOT,RoPS and TOLDI).Experimental results validate the high repeatability,robustness,universality and time efficiency of our method.
基金The National Key R&D Program of China under contract No.2018YFB0504900the National Natural Science Foundation of China under contract Nos 41406204 and 41501417Operational Support Service System For Natural Resources Satellite Remote Sensing。
文摘Wanshan area has been chosen to be the specified field to calibrate and validate(Cal/Val)the HY-2 altimeter and its follow-on satellites.In March 2018,an experiment has been conducted to determine the sea surface height(SSH)under the HY-2 A ground track(Pass No.203).A GPS towing-body(GPS-TB)was designed to measure the SSH covering an area of about 6 km×28 km wide centered on the HY-2 A altimeter satellite ground track.Three GPS reference stations,one tide gauge and a GPS buoy were placed in the research area,in order to process and resolve the kinematic solution and check the precision of the GPS-TB respectively.All the GPS data were calculated by the GAMIT/GLOBK software and TRACK module.The sea surface was determined by the GPS-TB solution and the tide gauge placed on Zhiwan Island.Then the sea surface of this area was interpolated by Arc GIS10.2 with ordinary Kriging method.The results showed that the precision of the GPS-TB is about 1.10 cm compared with the tide gauge placed nearby,which has an equivalent precision with the GPS buoy.The interpolated sea surface has a bias of–1.5–4.0 cm with standard deviation of 0.2–2.4 cm compared with the checking line.The gradient of the measured sea surface is about 1.62 cm/km along the HY-2 orbit which shows a good agreement compared with the CLS11 mean sea surface(MSS).In the Cal/Val of satellites,the sea surface between the tide gauge/GPS buoy and the footprint of altimeter can be improved by this work.
文摘Our study aims to determine diagnostic reference levels (DRL) for chest front examination in postero anterior (PA) for optimizing patient entrance surface dose (ESD) and dose-area product (DAP) of patients in west of Côte d’Ivoire. 90 patients from three hospitals undergoing conventional radiology were considered. The ESD and DAP for each patient were obtained during chest radiography (PA) examination. The measurements were performed with the device call Dose-Area Product-meter (DAP-meter) with brand Diamentor M4-KDK, type 11017. The DRL were obtained in applying the 75th percentile statistical method to the obtained ESD and DAP. The obtained DRL in ESD for chest radiography for all rooms is 0.40 mGy and in DAP is 54.85 cGy·cm2. Our DRL for ESD is higher than those obtained in Abidjan District and in other countries like UK and Cameroon. Our DRL for DAP is higher than those from Abidjan and all other countries for which a similar study was made. The comparison of these values to those from Abidjan and other countries, shows us that radiology technicians can make efforts to choose radiological parameters to reduce ESD. They must use convenable the X-rays tube to reduce DAP by reducing the patient exposure surface.
基金V. ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China （No.20725312 and No.20533060） and the Ministry of Science and Technology （No.2007CB815201）.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11304185 and 11074151)China Postdoctoral Science Foundation(Grant No.2014M561957)+1 种基金the Postdoctoral Innovation Project of Shandong Province,China(Grant No.201402013)the Shandong Provincial Natural Science Foundation,China(Grant No.ZR2014AM022)
文摘A globally accurate potential energy surface is reported for the electronic ground-state H2O＋. The ab initio energies utilized to map the potential energy surface are calculated at the multireference configuration interaction method employing the aug-cc-pVQZ basis set and the full valence complete active space wave function as reference. In order to improve accu- racy of the resulting raw ab initio energies, they are then extrapolated to the complete basis set limit and most importantly to the full configuration-interaction limit by semiempirically correcting the dynamical correlation using the double many- body expansion-scaled external correlation method. The topographical features of the current potential energy surface were examined in detail, which agree nicely with those of other theoretical work.
