China is one of the ancient civilization countries. Owing to the blind reclamation, the vegetation had been destroyed, causing soil erosion and desertification, and making the civilization center move to the Changjian...China is one of the ancient civilization countries. Owing to the blind reclamation, the vegetation had been destroyed, causing soil erosion and desertification, and making the civilization center move to the Changjiang (Yangtze) River valley from the Huanghe (Yellow) River. This movement began in the Qin and Han dynasties (221 B.C-220 A.D.) because at that time the large-scale reclamation was felled, the grassland was reclaimed into farmland, the vegetation was seriously destroyed in the loess and north of the Huanghe River, and the climate was getting colder; and the turn from north to south occurred in the Sui and Tang dynasties (581-907 A.D.) and completed in the Song Dynasty (960-1279 A.D.). However, at present the vegetation damage of the Changjiang River valley is very serious too and the silt carrying capacity of the Changjiang River is increasing sharply; thus the Changjiang River is in danger of becoming a second Huanghe River, so we must pay attention to the protection of ecological展开更多
The correction for antenna phase center is considered in processing Global Positioning System （GPS） data collected from a network of GPS ultra-short baselines. Compared with the leveling measurements, the GPS result...The correction for antenna phase center is considered in processing Global Positioning System （GPS） data collected from a network of GPS ultra-short baselines. Compared with the leveling measurements, the GPS results show that the relative vertical offsets for the pairs of GPS receiver antenna phase centers still exist, although absolute calibration of the antenna phase center variations （PCVs） has been considered. With respect to the TPS CR.G3 antenna, the relative vertical offset for the LEI AT504 antenna is 8.4 mm, the offset for the ASH701945C_M antenna is 5.5 mm, and those for the ASHY00936E_C and ASH701945B_M antennas are approximately between 2 mm and -3 mm. The relative offsets for the same type of antennas are approximately 1 mm. By correcting the absolute PCVs, the existing relative offset becomes negligible for horizontal positioning.展开更多
为研究不同道路监控补光灯对驾驶员眩光的影响程度,挑选10名视力正常受试者夜晚驾车经过城市、郊区、高速3种不同环境路段,使用照度计测量不同路段补光灯及补光灯环境照度,采用Tobii Pro Glasses 2眼动仪获取眼动特征数据,分析驾驶员瞳...为研究不同道路监控补光灯对驾驶员眩光的影响程度,挑选10名视力正常受试者夜晚驾车经过城市、郊区、高速3种不同环境路段,使用照度计测量不同路段补光灯及补光灯环境照度,采用Tobii Pro Glasses 2眼动仪获取眼动特征数据,分析驾驶员瞳孔直径变化程度及瞳孔中心位移变化。研究结果表明:驾驶员在不同道路监控补光灯照明刺激下,人眼运动会发生不同程度变化。郊区道路瞳孔直径变化最大可达32%左右,是城市道路及高速道路的3倍左右。郊区道路监控补光灯照度以及补光灯环境照度差距明显,增大驾驶员暗适应时间,在3 s内瞳孔直径未能恢复正常,造成视物不清。同时在郊区道路驾驶员瞳孔中心位置偏移至视角范围为5°~220°的边缘区域远离中央窝区,造成视野模糊。研究结果可为驾驶员夜间安全驾驶提供数据支撑及应对措施。展开更多
目的:观察垫对髁突运动中心位置的影响,并探讨下颌定位技术测定髁突运动中心电子位置(ele-ctronic position analysis,EPA)指导垫调磨的方法。方法:从3158例颞下颌关节紊乱病患者中,选择46例(92侧关节)有下颌绞锁运动症状的颞下颌...目的:观察垫对髁突运动中心位置的影响,并探讨下颌定位技术测定髁突运动中心电子位置(ele-ctronic position analysis,EPA)指导垫调磨的方法。方法:从3158例颞下颌关节紊乱病患者中,选择46例(92侧关节)有下颌绞锁运动症状的颞下颌关节紊乱病患者,接受下颌稳定垫治疗;常规调磨后,为患者戴入合垫,再用超声三维下颌定位仪(3D-ultrasonic navigator)进行髁突运动中心电子位置及下颌运动功能分析,观察常规方法调磨后垫治疗对髁突运动中心的影响;对引起双侧髁突运动中心不均衡位移的病例,则根据EPA的测试,对垫进行修正性调磨。结果:常规调磨后,67.4%(31/46)的患者双侧髁突运动中心在矢状位的位移距离明显不均衡;63%(29/46)的患者双侧髁突运动中心的位移方向不一致;而根据EPA检测修正性调磨后,91.3%(42/46)的患者双侧髁突运动中心的位移方向达到了一致。常规调磨与修正性调磨对垫引起髁突运动中心位移时双侧的均衡性与方向一致性上的差异均具有统计学意义。结论:稳定垫治疗颞下颌关节紊乱病过程中,超声三维下颌定位仪中的EPA检测指导下进行修正性调磨可以提高双侧髁突运动中心的位移距离和方向的一致性。展开更多
文摘China is one of the ancient civilization countries. Owing to the blind reclamation, the vegetation had been destroyed, causing soil erosion and desertification, and making the civilization center move to the Changjiang (Yangtze) River valley from the Huanghe (Yellow) River. This movement began in the Qin and Han dynasties (221 B.C-220 A.D.) because at that time the large-scale reclamation was felled, the grassland was reclaimed into farmland, the vegetation was seriously destroyed in the loess and north of the Huanghe River, and the climate was getting colder; and the turn from north to south occurred in the Sui and Tang dynasties (581-907 A.D.) and completed in the Song Dynasty (960-1279 A.D.). However, at present the vegetation damage of the Changjiang River valley is very serious too and the silt carrying capacity of the Changjiang River is increasing sharply; thus the Changjiang River is in danger of becoming a second Huanghe River, so we must pay attention to the protection of ecological
基金supported by the Science for Earthquake Resilience(XH14070Y,XH15064Y)the China NationalSpecial Fund for Earthquake Scientific Research in Public Interest(201208009)
文摘The correction for antenna phase center is considered in processing Global Positioning System （GPS） data collected from a network of GPS ultra-short baselines. Compared with the leveling measurements, the GPS results show that the relative vertical offsets for the pairs of GPS receiver antenna phase centers still exist, although absolute calibration of the antenna phase center variations （PCVs） has been considered. With respect to the TPS CR.G3 antenna, the relative vertical offset for the LEI AT504 antenna is 8.4 mm, the offset for the ASH701945C_M antenna is 5.5 mm, and those for the ASHY00936E_C and ASH701945B_M antennas are approximately between 2 mm and -3 mm. The relative offsets for the same type of antennas are approximately 1 mm. By correcting the absolute PCVs, the existing relative offset becomes negligible for horizontal positioning.
文摘为研究不同道路监控补光灯对驾驶员眩光的影响程度,挑选10名视力正常受试者夜晚驾车经过城市、郊区、高速3种不同环境路段,使用照度计测量不同路段补光灯及补光灯环境照度,采用Tobii Pro Glasses 2眼动仪获取眼动特征数据,分析驾驶员瞳孔直径变化程度及瞳孔中心位移变化。研究结果表明:驾驶员在不同道路监控补光灯照明刺激下,人眼运动会发生不同程度变化。郊区道路瞳孔直径变化最大可达32%左右,是城市道路及高速道路的3倍左右。郊区道路监控补光灯照度以及补光灯环境照度差距明显,增大驾驶员暗适应时间,在3 s内瞳孔直径未能恢复正常,造成视物不清。同时在郊区道路驾驶员瞳孔中心位置偏移至视角范围为5°~220°的边缘区域远离中央窝区,造成视野模糊。研究结果可为驾驶员夜间安全驾驶提供数据支撑及应对措施。
文摘目的:观察垫对髁突运动中心位置的影响,并探讨下颌定位技术测定髁突运动中心电子位置(ele-ctronic position analysis,EPA)指导垫调磨的方法。方法:从3158例颞下颌关节紊乱病患者中,选择46例(92侧关节)有下颌绞锁运动症状的颞下颌关节紊乱病患者,接受下颌稳定垫治疗;常规调磨后,为患者戴入合垫,再用超声三维下颌定位仪(3D-ultrasonic navigator)进行髁突运动中心电子位置及下颌运动功能分析,观察常规方法调磨后垫治疗对髁突运动中心的影响;对引起双侧髁突运动中心不均衡位移的病例,则根据EPA的测试,对垫进行修正性调磨。结果:常规调磨后,67.4%(31/46)的患者双侧髁突运动中心在矢状位的位移距离明显不均衡;63%(29/46)的患者双侧髁突运动中心的位移方向不一致;而根据EPA检测修正性调磨后,91.3%(42/46)的患者双侧髁突运动中心的位移方向达到了一致。常规调磨与修正性调磨对垫引起髁突运动中心位移时双侧的均衡性与方向一致性上的差异均具有统计学意义。结论:稳定垫治疗颞下颌关节紊乱病过程中,超声三维下颌定位仪中的EPA检测指导下进行修正性调磨可以提高双侧髁突运动中心的位移距离和方向的一致性。
