基于虚拟仪器技术的自动气象站数据采集与处理系统

在XYZ06型地面遥测气象仪的基础上,基于虚拟仪器技术研制了一套气象要素自动采集与处理系统,替代了该气象仪的数据采集器和数据预处理器的功能,可进行温度、湿度的采集、处理、显示、保存和发送.插入该气象仪终端计算机的数据采集卡ACL-8216能与气象仪的观测业务软件通讯,通讯命令字及其意义可实时显示于屏幕上.该虚拟气象数据采集器可方便地应用于自动气象站的教学实践,并可大大降低实验的设备费用.     

自动气象站地表温度测量方式的改进

针对目前各地自动气象站两种地表温度的测量方式,即：四支传感器组合模式和单支传感器测量模式共存的现状,从分析地温传感器的测量技术以及信号采集原理人手,探讨了一种可以将四支温度传感器化简成为单支温度传感器的方法。经过改进后的测量方式,符合中国气象局《地面气象观测规范》（2003）的要求,保证了各个自动气象站之间地温测量方式的一致性和可比性。同时,该方式能够有效地降低地温传感器的隐性故障概率,减少自动气象站的维护成本。     

STATISTIC CHARACTERISTICS OF MCSS OVER ASIA AND WESTERN PACIFIC REGION

Mesoscale convective systems (MCSs) are severe disaster-producing weather systems. Previous attempts of MCS census are made by examining infrared satellite imageries artificially, with subjectivity involved in the process unavoidably. This method is also inefficient and time-consuming. The disadvantages make it impossible to do MCS census over Asia and western Pacific region (AWPR) with an extended span of time, which is not favorable for gaining a deeper insight into these systems. In this paper, a fire-new automatic MCS identification (AMI) method is used to capture four categories of MCSs with different sizes and shapes from numerical satellite infrared data. 47,468 MCSs are identified over Asia and western Pacific region during the warm season (May to October) from 1995 to 2008. Based on this database, MCS characteristics such as shape, size, duration, velocity, geographical distribution, intermonthly variation, and lifecycle are studied. Results indicate that the number of linear MCSs is 2.5 times that of circular MCSs. The former is of a larger size while the latter is of a longer duration. The 500 hPa steering flow plays an important role in the MCS movement. MCSs tend to move faster after they reach the maximum extent. Four categories of MCS have similar characteristics of geographical distribution and intermonthly variation. Basically, MCSs are zonally distributed, with three zones weakening from south to north. The intermonthly variation of MCSs is related to the seasonal adjustment of the large-scale circulation. As to the MCSs over China, they have different lifecycle characteristics over different areas. MCSs over plateaus and hill areas, with only one peak in their lifecycle curves, tend to form in the afternoon, mature at nightfall, and dissipate at night. On the other hand, MCSs over plains, which have several peaks in their lifecycle curves, may form either in the afternoon or at night, whereas MCSs over the oceans tend to form at midnight. Affected by the sea-land breeze circulation, MCSs over coastal areas of Guangdong and Guangxi always come into being at about 1500 or 1600 (local time), while MCSs over the Sichuan Basin, affected by the mountain-valley breeze circulation, generally initiate nocturnally.     

基于空间特性的立交桥自动检测方法

针对城市复杂立交桥的空间特性,提出了集成激光雷达数据和遥感影像实施立交桥的快速自动检测的技术流程和关键技术,突破了利用传统遥感影像难以实现立交桥自动检测难题。实际数据验证了整个流程和关键技术的可行性和有效性。     

航空遥感影像阴影的自动检测与补偿

通过对阴影特性进行分析,选取能够有效检测阴影的特征组合,改进了Otsu阈值算法,可以自动获取各特征的合适阈值,实现阴影的自动检测;同时提出了改进的Wallis滤波阴影补偿策略,突出阴影区域的地物信息。实验结果表明,该检测算法阴影补偿效果明显,真实再现了被阴影遮蔽的地物细节。     

测角网间接平差中近似坐标自动概算算法设计

在对测角网进行平差计算时,网中未知点平面坐标的概算是一个关键问题。针对测角网的特点,设计了测角网近似坐标自动概算的算法,用实例验证了算法的正确性及可靠性,避免了繁琐的手工近似计算过程,提高了数据处理的效率。     

浮船坞标校的一种新方法

针对浮船坞标校的特点,提出了利用动态 GPS进行标校的新方法.该方法可连续获取被试设备位置信息,从中挑取与被试设备自身测量同历元的 GPS数据进行方位标数据解算,然后与设备测得的数据进行比对,可有效提高浮船坞标校精度.从而解决了动态标校的实时性、一致性和准确性问题,在实际应用中取得较好效果.     

基于多特征空间的遥感信息自动提取方法

根据目视判读的原理提出了基于多特征空间的遥感信息自动提取方法,将地物在地理空间和影像空间的多种特征空间要素分为光谱特征空间、形状特征空间、干扰特征空间和区域地学特征空间.通过对多特征空间的数学描述和计算机处理实现遥感信息的自动提取.基于多特征空间的遥感信息自动提取方法是一种对人脑判读的计算机模拟,可以提高专题信息的提取效率,是对影像空间符号化的一种尝试,如果实现了多特征空间的完全数学表示就能够实现遥感信息的自动提取.     

四分量钻孔应变观测的实地相对标定

提出钻孔应变观测的实地标定问题有相对标定和绝对标定两层涵义;讨论了四分量钻孔应变观测的相对标定的归一化新方法：将前人标定应力观测的方法用于应变观测。一方面大大简化了计算公式,另一方面提出轮流以每个元件为标准计算灵敏度而后取平均值的方法。在统计上更为合理;并以昌平台RZB-1型钻孔应变观测为例进行实际应用,取得了令人满意的结果。     

超宽与甚宽频带地震计阶跃标定的加权动态拟合法

阐述了由阶跃响应确定超宽频带与甚宽频带地震计二阶系统传递函数的特征参数的方法。首先分析了现有的曲线拟合法在测试精度、收敛速度、拟合方法的通用性等方面存在的不足,然后给出了一种更加完善的精确求取二阶系统传递函数特征参数的方法——加权动态拟合法,详细论述了加权动态拟合法的数学原理,并设计了拟合计算程序。