空间大地测量技术实测台站速度场精度分析

利用国际上3个著名的数据分析处理中心CSR、JPL和GSFC给出的3种空间大地测量技术实测的台站运动速度场数据,解算不同空间技术速度场之间的转换参数,即速度场之间的系统差。在扣除两两技术之间速度场的系统差后,用速度场残差计算了空间技术速度场之间的不符值加权中误差作为衡量不同空间技术实测台站速度场的外部检核指标,即外符精度。计算结果表明,VLBI和GPS实测台站地心速度已经达到1 mm/a的精度;SLR实测台站地心速度已经达到2 mm/a的精度。     

Estimating surface ice velocity on Chhota Shigri glacier from satellite data using Particle Image Velocimetry (PIV) technique

Information about the surface ice velocity is one of the important parameters for Mass balance and Glacier dynamics. This study estimates the surface ice velocity of Chhota Shigri glacier using Landsat (TM/ETM+) and ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) temporal data-sets from a period of 2009 to 2016 and 2006 to 2007, respectively. A correlation based Particle Image Velocimetry (PIV) technique has been used for the estimation of surface ice velocity. This technique uses multiple window sizes in the same data-set. Four window sizes (low, medium, high, very high) are used for each image pair. Estimated results have been compared with the published data. The outcomes attained from the medium window size closely matches with the published results. The estimated mean surface ice velocities of medium window size are 24 and 28.5 myr^?1 for 2009/2010 and 2006/2007 images pair. Highest velocity is observed in middle part of the glacier while lowest in the accumulation zone of the glacier.     

提高河口地区水下地形测量精度的方法

采用配备多元传感器的高精度的无验潮水下地形测量模式、根据测区温度和盐度变化采用声速仪对声速进行实时改正、对系统时延进行准确的改正、正确的测量数据处理等来提高河口地区水下地形测量精度。     

一定分布模式下的最优Lp估计

观测数据在一定的分布模式下,需从理论上解决究竟用多大的ｐ值进行Ｌｐ估计（最优ｐ值的确定）,本文基于渐近方差整体最小的原则,给出了最优Ｌｐ估计的定义。观测数据中含有粗差（异常值）的扰动,其误差分布可视为污染分布,作者分析了最优ｐ值的大小,结果表明,若观测数据中含有不同大小、数量的粗差,为使Ｌｐ估计差最小,则ｐ将取［１．２,１．５］中的某一定值,Ｌｐ估计结果最优,此结论对测量数据处理具有一定的参考价值     

Modeling the risk of spread and establishment for Asian longhorned beetle (Anoplophora glabripennis) in Massachusetts from 2008-2009

Land managers responsible for invasive species removal in the USA require tools to prevent the Asian longhorned beetle (Anoplophora glabripennis) (ALB) from decimating the maple-dominant hardwood forests of Massachusetts and New England. Species distribution models (SDMs) and spread models have been applied individually to predict the invasion distribution and rate of spread, but the combination of both models can increase the accuracy of predictions of species spread over time when habitat suitability is heterogeneous across landscapes. First, a SDM was fit to 2008 ALB presence-only locations. Then, a stratified spread model was generated to measure the probability of spread due to natural and human causes. Finally, the SDM and spread models were combined to evaluate the risk of ALB spread in Central Massachusetts in 2008–2009. The SDM predicted many urban locations in Central Massachusetts as having suitable environments for species establishment. The combined model shows the greatest risk of spread and establishment in suitable locations immediately surrounding the epicentre of the ALB outbreak in Northern Worcester with lower risk areas in suitable locations only accessible through long-range dispersal from access to human transportation networks. The risk map achieved an accuracy of 67% using 2009 ALB locations for model validation. This model framework can effectively provide risk managers with valuable information concerning the timing and spatial extent of spread/establishment risk of ALB and potential strategies needed for effective future risk management efforts.     

SOE技术在测绘成果网络分发服务系统中的应用研究

作为测绘信息化的重要组成部分,测绘成果网络分发服务系统的建设提升了测绘成果信息化管理水平,促进了测绘成果的推广应用。本文在总结福建省测绘成果网络分发服务系统建设成果的基础上,基于SOE技术解决其在推广应用过程中存在问题,提高了测绘成果的公共服务能力与水平。     

人工心肺机流量计的研制

本文介绍了如何应用单片微型计算机和光电传感器组成人工心肺机(或称体外循环机)流量计。该仪器对人工心肺机的泵的各种转速能够准确地采集,对不同的患者能够精确地计算出所需血液流量,从而定量地控制输送给病人的血液流量,以保证心脏手术顺利进行,改变了临床手术时手工计算的落后情况。流量计是一台新型的智能化仪表。     

干旱区地下水位降幅空间分布特性研究

基于GIS和地理统计学的理论、方法对所取观测井地下水位降幅数据进行空间分布特征分析。结果表明:数据服从正态分布,结构符合球状模型,空间数据存在东西方向和南北方向的二价函数趋势;地下水位降幅由北向南呈环状递减,最深降幅达30m,绿洲群大部分居于20～30m降幅之间,为地下水开采密集区,大于10m降幅的面积约69300hm2。利用Kriging最优内插法生成等值线图,可以更准确和直观地展示整个研究区的地下水资源状况、生态环境可能发生退化的区域及未来发展方向。     

Detecting patterns of climate change in long-term forecasts of marine environmental parameters

ABSTRACT

Forecasting environmental parameters in the distant future requires complex modelling and large computational resources. Due to the sensitivity and complexity of forecast models, long-term parameter forecasts (e.g. up to 2100) are uncommon and only produced by a few organisations, in heterogeneous formats and based on different assumptions of greenhouse gases emissions. However, data mining techniques can be used to coerce the data to a uniform time and spatial representation, which facilitates their use in many applications. In this paper, streams of big data coming from AquaMaps and NASA collections of 126 long-term forecasts of nine types of environmental parameters are processed through a cloud computing platform in order to (i) standardise and harmonise the data representations, (ii) produce intermediate scenarios and new informative parameters, and (iii) align all sets on a common time and spatial resolution. Time series cross-correlation applied to these aligned datasets reveals patterns of climate change and similarities between parameter trends in 10 marine areas. Our results highlight that (i) the Mediterranean Sea may have a standalone ‘response’ to climate change with respect to other areas, (ii) the Poles are most representative of global forecasted change, and (iii) the trends are generally alarming for most oceans.     

基于蓝牙定位的老年人室内跌倒监护系统设计

随着全球老龄化的加剧,老年人口的增多,老年人的健康监护已经成为了重要的社会问题。因身体机能的下降,老年人发生跌倒的概率非常高,而老年人一天中大约90%的时间是处于室内,针对老年人室内意外跌倒的医护救治,设计了一款基于蓝牙定位的老年人室内跌倒监护系统。该系统通过集成的传感器采集加速度、角速度、室内位置、人体生理信息等数据,并通过计算分析实现了跌倒监测报警功能。