在多波束测深系统的换能器安装与使用过程中,由于无法保证换能器坐标系统与船体坐标系统完全重合,因此必须进行横摇、纵倾以及航向偏差校准与改正,使两者坐标系统相一致。详细分析了多波束测深系统换能器安装校准的原理和方法,以"...在多波束测深系统的换能器安装与使用过程中,由于无法保证换能器坐标系统与船体坐标系统完全重合,因此必须进行横摇、纵倾以及航向偏差校准与改正,使两者坐标系统相一致。详细分析了多波束测深系统换能器安装校准的原理和方法,以"亚美通道"海底光缆路由调查中,挪威Simrad EM 3000多波束测深系统的安装与校准为例,阐述了其安装校准方法及在海底地形测量中的应用。展开更多
Data from the Beijing SAFIR 3000 lightning detection system and Doppler radar provided some insights into the three-dimensional lightning structure and evolution of a leading-line and trailing-stratiform （LLTS） meso...Data from the Beijing SAFIR 3000 lightning detection system and Doppler radar provided some insights into the three-dimensional lightning structure and evolution of a leading-line and trailing-stratiform （LLTS） mesoscale convective system （MCS） over Beijing on 31 July 2007. Most of the lightning in the LLTS-MCS was intracloud （IC） lightning, while the mean ratio of positive cloud-to-ground （＋CG） lightning to –CG lightning was 1：4, which was higher than the average value from previous studies. The majority of CG lightning occurred in the convective region of the radar echo, particularly at the leading edge of the front. Little IC lightning and little ＋CG lightning occurred in the stratiform region. The distribution of the CG lightning indicated that the storm had a tilted dipole structure given the wind shear or the tripole charge structure. During the storm’s development, most of the IC lightning occurred at an altitude of ～9.5 km; the lightning rate reached its maximum at 10.5 km, the altitude of IC lightning in the mature stage of the storm. When the thunderstorm began to dissipate, the altitude of the IC lightning decreased gradually. The spatial distribution of lightning was well correlated with the rainfall on the ground, although the peak value of rainfall appeared 75 min later than the peak lightning rate.展开更多
给出一种CENTU MC S3000集散控制系统中分离信号软件模块的分程控制方案。提出利用该模块的信号分配功能，可以产生一种新型分程控制模式，即不必调整阀门定位器的机电机构就能使送到两个控制阀的输入信号范围均为0％-100％。通过应用...给出一种CENTU MC S3000集散控制系统中分离信号软件模块的分程控制方案。提出利用该模块的信号分配功能，可以产生一种新型分程控制模式，即不必调整阀门定位器的机电机构就能使送到两个控制阀的输入信号范围均为0％-100％。通过应用软件组态能够实现分程控制。这种方法具有工程实施省时省力、节省资金，控制效果更加准确可靠等优点，克服了传统分程控制参数调整不方便且稳定性较差等缺点。在石油化工企业的釜式间歇反应器温度分程控制和精馏塔塔压分程控制等系统中，有着广泛的应用前景。展开更多
目的探讨提高GEM Premier 3000血气分析仪检测结果准确性的有效措施。方法按照分析前、分析中和分析后三个阶段,对1986例血气分析中检测失败或检测结果与临床不符者共141例进行总结分析,明确影响GEM Premier 3000血气分析仪检测准确性...目的探讨提高GEM Premier 3000血气分析仪检测结果准确性的有效措施。方法按照分析前、分析中和分析后三个阶段,对1986例血气分析中检测失败或检测结果与临床不符者共141例进行总结分析,明确影响GEM Premier 3000血气分析仪检测准确性的各因素构成。结果影响GEM Premier 3000血气分析仪检测准确性的分析前因素占74.5%、分析中因素占20.6%、分析后因素占2.8%,原因不明占2.1%。结论血气分析结果的准确测得需要临床医护人员和临床检验人员的密切协作。展开更多
文摘在多波束测深系统的换能器安装与使用过程中,由于无法保证换能器坐标系统与船体坐标系统完全重合,因此必须进行横摇、纵倾以及航向偏差校准与改正,使两者坐标系统相一致。详细分析了多波束测深系统换能器安装校准的原理和方法,以"亚美通道"海底光缆路由调查中,挪威Simrad EM 3000多波束测深系统的安装与校准为例,阐述了其安装校准方法及在海底地形测量中的应用。
基金supported by the National Natural Science Foundation of China(Grant No. 40930949)Key Subject Project of Beijing Atmospheric Physics and Environment,the One Hundred Person Project of the Chinese Academy of Sciences
文摘Data from the Beijing SAFIR 3000 lightning detection system and Doppler radar provided some insights into the three-dimensional lightning structure and evolution of a leading-line and trailing-stratiform （LLTS） mesoscale convective system （MCS） over Beijing on 31 July 2007. Most of the lightning in the LLTS-MCS was intracloud （IC） lightning, while the mean ratio of positive cloud-to-ground （＋CG） lightning to –CG lightning was 1：4, which was higher than the average value from previous studies. The majority of CG lightning occurred in the convective region of the radar echo, particularly at the leading edge of the front. Little IC lightning and little ＋CG lightning occurred in the stratiform region. The distribution of the CG lightning indicated that the storm had a tilted dipole structure given the wind shear or the tripole charge structure. During the storm’s development, most of the IC lightning occurred at an altitude of ～9.5 km; the lightning rate reached its maximum at 10.5 km, the altitude of IC lightning in the mature stage of the storm. When the thunderstorm began to dissipate, the altitude of the IC lightning decreased gradually. The spatial distribution of lightning was well correlated with the rainfall on the ground, although the peak value of rainfall appeared 75 min later than the peak lightning rate.
文摘给出一种CENTU MC S3000集散控制系统中分离信号软件模块的分程控制方案。提出利用该模块的信号分配功能，可以产生一种新型分程控制模式，即不必调整阀门定位器的机电机构就能使送到两个控制阀的输入信号范围均为0％-100％。通过应用软件组态能够实现分程控制。这种方法具有工程实施省时省力、节省资金，控制效果更加准确可靠等优点，克服了传统分程控制参数调整不方便且稳定性较差等缺点。在石油化工企业的釜式间歇反应器温度分程控制和精馏塔塔压分程控制等系统中，有着广泛的应用前景。
文摘目的探讨提高GEM Premier 3000血气分析仪检测结果准确性的有效措施。方法按照分析前、分析中和分析后三个阶段,对1986例血气分析中检测失败或检测结果与临床不符者共141例进行总结分析,明确影响GEM Premier 3000血气分析仪检测准确性的各因素构成。结果影响GEM Premier 3000血气分析仪检测准确性的分析前因素占74.5%、分析中因素占20.6%、分析后因素占2.8%,原因不明占2.1%。结论血气分析结果的准确测得需要临床医护人员和临床检验人员的密切协作。
