To provide genetic information and materials for breeding hybrid japonica rice with wide adaptability and strong competitive advantage of yield, elite alleles and their carrier varieties of growth duration （GD） and ...To provide genetic information and materials for breeding hybrid japonica rice with wide adaptability and strong competitive advantage of yield, elite alleles and their carrier varieties of growth duration （GD） and productive panicle number per plant （PN） were detected. A natural population composed of 94 japonica varieties was phenotyped for the GD, PN and plant height （PH） in two environments. The conditional phenotypic data were transferred by the linear model method in software QGAStation 1.0, and association mapping based on the unconditional and conditional phenotype values of GD and PN was analyzed by using general linear model in software TASSEL. A total of 34 simple sequence repeat （SSR） marker loci associated with GD and PN were detected in the two environments. Among them, 15 were associated with GD, and 19 were associated with PN. Four elite alleles of RM8095-120bp, RM7102-176bp, RM72-170bp and RM72-178bp were associated with GD, and their carrier varieties were Hongmangshajing, Nipponbare, Hongmangshajing and Nannongjing 62401, respectively. These elite alleles from the carrier varieties can shorten GD by 2.03-9.93 d when they were introduced into improved materials. RM72-182bp associated with PN was an elite allele, and its carrier variety was Xiaoqingzhong. It can increase PN by three when introduced into improved materials. Moreover, these elite alleles can be used to improve target traits without influencing another two traits.展开更多
This paper presents an analysis of four open-source Global Digital Elevation Models (GDEMs) and compares them on two topographic profiles (nearly flat, and hills regions) for mapping and geomatics applications. The ch...This paper presents an analysis of four open-source Global Digital Elevation Models (GDEMs) and compares them on two topographic profiles (nearly flat, and hills regions) for mapping and geomatics applications. The chief intention is to investigate if GDEMs-based heights, contour intervals, slopes, and topographic profiles are valid for all map scales of topographic mapping, which constitutes a major issue in mapping activities. Two case studies, the Nile delta in Egypt and Makkah city in Saudi Arabia, have been utilized to represent flat and moderate-topography patterns. The investigated GDEMs include the most-recent released models: ASTER v.3, ACE 2, SRTMGL1 v.3, and NASADEM_HGT v.1 released in 2019 and 2020 with spatial resolutions of 1 and 3 arc seconds. Available accurate Ground Control Points (GCP) consist of 540 stations in the Nile delta and 175 stations in Makkah. Based on the available datasets in two study areas, it has been found that the accuracy of investigated GDEMs over known checkpoints ranges from ±2.5 and ±5.1 meters in the Nile delta region, while it varies between ±5.1 and ±8.0 meters in the Makkah area. That indicates that the utilization of GDEMs in topographic mapping differs significantly between flat and hilly spatial regions. Therefore, it is recommended to avoid using GDEMs for developing topographic maps of scale 1:25,000 or larger in flat regions and map scale 1:50,000 or larger in hilly regions. Additionally, the accomplished results showed that all GDEM-based slopes do not match with the actual slopes from known GCP over cross section’s length up to 30 kilometers. Thus, it is concluded that GDEMs are not the appropriate heights’ source for topographic mapping at medium and large map scales, and could not be utilized for topographic profiling in precise engineering and geomatics applications.展开更多
According to the characteristic of global positioning system（GPS） reflection signals,a GPS delay mapping receiver system scheme is put forward,which not only satisfies the unmanned aerial vehicle（UAV） guidance loc...According to the characteristic of global positioning system（GPS） reflection signals,a GPS delay mapping receiver system scheme is put forward,which not only satisfies the unmanned aerial vehicle（UAV） guidance localization but also realizes height measurement.A code delay algorithm is put forward,which processes the direct and land reflected signal and outputs the navigation data and specular point.The GPS terrain reflected echo signal mathematical equation is inferred.The reflecting signal area,when the GPS signal passes the land,is analyzed.The height survey model reflected land surface characteristic is established.A simulation system which carries guidance localization of the UAV and the height measuring control through the GPS direct signal and the land reflected signal is designed,taken the GPS satellite as the illumination source,the receiver is put on the UAV.Then the UAV guidance signal,the GPS reflection signal and receiver＇s parallel processing are realized.The parallel processing reduces UAV＇s payload and raises system＇s operating efficiency.The simulation results confirms the validity of the model and also provides the basis for the UAV＇s optimization design.展开更多
针对同步定位与建图(simultaneous localization and mapping,SLAM)在户外环境中定位与建图鲁棒性、准确性不足的问题,提出了一种基于半直接法的高度激光里程计(height laser odometer based on semi-direct method,SLO)。与现有的激光...针对同步定位与建图(simultaneous localization and mapping,SLAM)在户外环境中定位与建图鲁棒性、准确性不足的问题,提出了一种基于半直接法的高度激光里程计(height laser odometer based on semi-direct method,SLO)。与现有的激光里程计算法相比,该方法避免了三维点云的显式计算,主动对三维点进行降维处理生成图片,避免了三角测量误差和单目视觉SLAM中的尺度不确定性和尺度漂移问题。在高度图的基础上结合了直接方法和间接方法,使得系统在使用迭代最近点算法(iterative closest point,ICP)进行帧间匹配时更稳定、更轻便并且计算量小。高度图的使用弥补了直接方法的灰度不变性假设的缺点,并减少了照明的影响。在KITTI数据集和井下作业自动导向车(automated guided vehicle,AGV)平台上的实验结果表明,本文提出的方法有较高的鲁棒性与准确性。展开更多
基金supported by the grants from the Chinese Natural Science Foundation(Grant No.31071398)the National Program on Super Rice Breeding,the Ministry of Agriculture(Grant No.2010-3)+1 种基金National High Technology Research and Development Program of China(Grant No.2006AA10Z1E8)the Provincial Program of ‘8812’,Zhejiang Province,China(Grant No.8812-1)
基金supported by the Program of National High Technology Research and Development, Ministry of Science and Technology, China (Grant No. 2010AA101301)the Program of Introducing Talents of Discipline to University in China (Grant No. B08025)+1 种基金the Program of Introducing International Advanced Agricultural Science and Technology in China (Grant No. 2006-G8 [4]-31-1) the Program of Science-Technology Basis and Conditional Platform in China (Grant No. 505005)
基金supported by the Program of National High Technology Research and Development,Ministry of Science and Technology,China(Grant No.2010AA101301)the Program of Introducing Talents of Discipline to University in China(Grant No.B08025)+1 种基金the Program of Introducing International Advanced Agricultural Science and Technology in China(Grant No.2006-G8[4]-31-1)the Program of Science-Technology Basis and Conditional Platform in China(Grant No.505005)
文摘To provide genetic information and materials for breeding hybrid japonica rice with wide adaptability and strong competitive advantage of yield, elite alleles and their carrier varieties of growth duration （GD） and productive panicle number per plant （PN） were detected. A natural population composed of 94 japonica varieties was phenotyped for the GD, PN and plant height （PH） in two environments. The conditional phenotypic data were transferred by the linear model method in software QGAStation 1.0, and association mapping based on the unconditional and conditional phenotype values of GD and PN was analyzed by using general linear model in software TASSEL. A total of 34 simple sequence repeat （SSR） marker loci associated with GD and PN were detected in the two environments. Among them, 15 were associated with GD, and 19 were associated with PN. Four elite alleles of RM8095-120bp, RM7102-176bp, RM72-170bp and RM72-178bp were associated with GD, and their carrier varieties were Hongmangshajing, Nipponbare, Hongmangshajing and Nannongjing 62401, respectively. These elite alleles from the carrier varieties can shorten GD by 2.03-9.93 d when they were introduced into improved materials. RM72-182bp associated with PN was an elite allele, and its carrier variety was Xiaoqingzhong. It can increase PN by three when introduced into improved materials. Moreover, these elite alleles can be used to improve target traits without influencing another two traits.
文摘This paper presents an analysis of four open-source Global Digital Elevation Models (GDEMs) and compares them on two topographic profiles (nearly flat, and hills regions) for mapping and geomatics applications. The chief intention is to investigate if GDEMs-based heights, contour intervals, slopes, and topographic profiles are valid for all map scales of topographic mapping, which constitutes a major issue in mapping activities. Two case studies, the Nile delta in Egypt and Makkah city in Saudi Arabia, have been utilized to represent flat and moderate-topography patterns. The investigated GDEMs include the most-recent released models: ASTER v.3, ACE 2, SRTMGL1 v.3, and NASADEM_HGT v.1 released in 2019 and 2020 with spatial resolutions of 1 and 3 arc seconds. Available accurate Ground Control Points (GCP) consist of 540 stations in the Nile delta and 175 stations in Makkah. Based on the available datasets in two study areas, it has been found that the accuracy of investigated GDEMs over known checkpoints ranges from ±2.5 and ±5.1 meters in the Nile delta region, while it varies between ±5.1 and ±8.0 meters in the Makkah area. That indicates that the utilization of GDEMs in topographic mapping differs significantly between flat and hilly spatial regions. Therefore, it is recommended to avoid using GDEMs for developing topographic maps of scale 1:25,000 or larger in flat regions and map scale 1:50,000 or larger in hilly regions. Additionally, the accomplished results showed that all GDEM-based slopes do not match with the actual slopes from known GCP over cross section’s length up to 30 kilometers. Thus, it is concluded that GDEMs are not the appropriate heights’ source for topographic mapping at medium and large map scales, and could not be utilized for topographic profiling in precise engineering and geomatics applications.
基金supported by the National High Technology Researchand Development Program of China(863 Program)(2008AA12A216)
文摘According to the characteristic of global positioning system（GPS） reflection signals,a GPS delay mapping receiver system scheme is put forward,which not only satisfies the unmanned aerial vehicle（UAV） guidance localization but also realizes height measurement.A code delay algorithm is put forward,which processes the direct and land reflected signal and outputs the navigation data and specular point.The GPS terrain reflected echo signal mathematical equation is inferred.The reflecting signal area,when the GPS signal passes the land,is analyzed.The height survey model reflected land surface characteristic is established.A simulation system which carries guidance localization of the UAV and the height measuring control through the GPS direct signal and the land reflected signal is designed,taken the GPS satellite as the illumination source,the receiver is put on the UAV.Then the UAV guidance signal,the GPS reflection signal and receiver＇s parallel processing are realized.The parallel processing reduces UAV＇s payload and raises system＇s operating efficiency.The simulation results confirms the validity of the model and also provides the basis for the UAV＇s optimization design.
文摘针对同步定位与建图(simultaneous localization and mapping,SLAM)在户外环境中定位与建图鲁棒性、准确性不足的问题,提出了一种基于半直接法的高度激光里程计(height laser odometer based on semi-direct method,SLO)。与现有的激光里程计算法相比,该方法避免了三维点云的显式计算,主动对三维点进行降维处理生成图片,避免了三角测量误差和单目视觉SLAM中的尺度不确定性和尺度漂移问题。在高度图的基础上结合了直接方法和间接方法,使得系统在使用迭代最近点算法(iterative closest point,ICP)进行帧间匹配时更稳定、更轻便并且计算量小。高度图的使用弥补了直接方法的灰度不变性假设的缺点,并减少了照明的影响。在KITTI数据集和井下作业自动导向车(automated guided vehicle,AGV)平台上的实验结果表明,本文提出的方法有较高的鲁棒性与准确性。
