地基多波段遥感大气可降水量研究

利用自动观测多波段CE 318太阳分光光度计，首先结合地面资料求出瑞利散射光学厚度，再用870 nm和1 020 nm非吸收通道内插出936 nm通道的气溶胶光学厚度。通过辐射传输模型MODTRAN模拟不同大气模式和观测角下的大气可降水量和透过率关系，利用改进的Langley 法计算出大气可降水量，分析了影响结果的误差源。     

用太阳光谱遥测大气污染气体NO_2的含量

利用地面可见光 (4 30— 45 0nm)波段的太阳光谱和大气上界的参考太阳光谱 ,反演出大气中NO2 的柱总含量 ,得到了该地区上空NO2 含量及其变化 ,其变化与当地环境监测站用常规法测量的NO2 浓度的变化基本一致。该文介绍了测量仪器、测量原理和部分测量结果     

叶绿素吸收的光合有效辐射比率的遥感估算模型研究

光合有效辐射比率（FPAR）是陆地生态系统碳循环研究的重要参数。根据FPAR的物理意义，本文提出了有效FPAR的概念：即叶绿素吸收的FPAR（FPARchl），利用模拟数据建立了有效FPAR信息模型。探讨了基于叶绿素含量估算有效FPAR的可行性，为进一步采用有效FPAR来估算NPP／GPP提供思路和途径。利用实测数据对有效FPAR模型进行验证表明：（1）叶片吸收的FPAR（FPARleaf）与有效FPAR（FPARchl）之间的差异较大。FPARchl通常不足FPARleaf的50％，两者之间虽存在一定的相关性，而这种相关性是非线性的；（2）叶绿素含量与FPARleaf的相关性较高，而与FPARchl的相关性更高，基于叶绿素含量可以以较高的精度估算FPARleaf和FPARchl经过验证，估算的平均相对误差分别为2．90％和6．6％；（3）应用模拟数据建立的FPARleaf及有效FPAR模型均在叶绿素含量大于20μg／cm。时估算的精度较高，而低于20μg／cm^2时估算的精度较低，本文中叶绿素含量大于20μg／cm^2的60个样本的FPARleaf及FPARchl的估算的平均相对误差，分别为1．79％和5．07％。     

太阳光度计反演大气水汽总量的方法与结果对比分析

详述了使用太阳光度计反演大气水汽柱总量的反演方法—单通道法和双通道法,其中双通道法又可采用不同 的非水汽通道来实现。考虑到气溶胶光学厚度及瑞利散射的影响,分析了不同方法反演所得水汽总量相对探空数据的 误差。结果表明,这些方法的反演结果非常接近。在实际应用中,可使用任一种方法来反演水汽。     

GPS数据解算对流层天顶总延迟探讨

运用GAMIT／GLOBK软件,对南极长城站与周边的各IGS跟踪站的GPS观测数据进行组网解算。在解算各站上空总天顶延迟的过程中,利用不同的星历进行解算,并对其解算结果进行了分析和探讨得出：实时预报。星历与精密星历在解算结果上差别不大,最小差值是0mm,最大差值仅为0．5mm。所以在计算各GPS站上空大气水汽含量时,可直接采用实时预报星历,对今后实时探测水汽及实时天气预报具有一定的实用意义。     

利用太阳直射光谱遥感大气柱水汽总量的研究

太阳光谱仪测得的直接辐射光谱含有大气水汽含量的信息。本文提出一种用太阳直射光谱反演大气柱水汽总量的方法。采用分子吸收的随机模式，而不是通常的Ｂｏｕｇｕｅｒ定理，处理水汽吸收，故更为合理。选取水汽的α，β和ρστ吸收带逐次扣除，联合订正，给出水汽含量。并与探空资料结果做了对比，有较好的一致性。     

黑龙江省大气水汽含量及其影响因素分析

大气水汽含量对海陆水循环、气溶胶和云的形成等具有重要作用,对其时空变化特征及其影响因素的研究具有十分重要的意义,而下垫面因素对其影响还有待进一步研究。以黑龙江省为研究区,基于MODIS、数字高程模型和探空数据,利用两通道和三通道比值法反演出大气水汽含量并进行精度评价。在此基础上,分析大气水汽含量的时空分布特征及其与下垫面之间的关系。研究结果表明:①两通道比值法要稍优于三通道比值法(与实测数据相关系数分别为0. 795和0. 754);②在4—7月间,黑龙江省西北部和东南部水汽含量低,而东部、西部水汽含量较高;③全省平均水汽含量整体呈上升趋势;④不同土地覆盖和地貌类型上空的水汽含量有着明显的差异。     

线性回归模型估算水稻叶片叶绿素含量的适宜性分析

利用PROSPECT模型模拟水稻叶片叶绿素含量从20．0μg/cm^2变化到40．0μg／cm^2时的叶片光谱特性，利用FCR模型模拟叶面积指数(LAI)为1，2，…，7时，不同地面状态下，4个不同观测方向的水稻冠层反射率。利用LAI为1，3，5，7时的模拟值，采用多元逐步回归分析法，从不同观测方向建立叶片叶绿素含量与冠层反射率(见)及其变化式ln(1／Rλ)，R’λ的多元线性回归模型，并用复相关系数和均方根差评价拟合精度，认为ln(1／Rλ)以及从天顶方向的拟合效果最好。利用从天顶方向建立的回归模型，预测叶片叶绿素含量，认为将该回归模型应用于其它方向是不合适的，从天顶方向预测时，预测精度受地面状态的影响，但总的说来，预测精度呈现随LAI的增大而提高的趋势。     

用太阳光谱遥测大气污染气体NO2的含量

利用地面可见光（430－450m)波段的太阳光谱和大气上界的参考太际光谱，反演出大气中NO2的柱总含量，得到了该地区上空NO2含量及其变化，其变化与当地环境监测站用常规法测量的NO2浓度的变化基本一致，该文介绍了测量仪器，测量原理和部分测量结果。     

大气水汽的红外遥感

本文讨论了利用差分吸收法来遥感大气中的水汽。水汽透过率用辐射计测量，水汽含量由我们自行编制的红外辐射大气透过率计算程序计算。在此同时还观测了气象参数，以确定光路上的水汽含量。结果表明，水汽长度的计算值和测量值非常吻合，回归曲线的相关系数达０．９７，均方根偏差为０．０１５ｇ／ｃｍ２。文中最后讨论误差来源和改善精度的途径，并指出对其它气体分子的吸收和气溶胶的消光进行修正的必要性。     

阿克苏河-塔里木河水系水质污染遥感监测与评价

 采用Landsat TM数据分析了阿克苏河—塔里木河断面水质污染状况,通过波段的DN值和常规监测数据建立能反映水质状况的 污染物监测模型。结果发现,将2000年常规监测数据代入模型后,与遥感数据的结果基本吻合| 重建阿克苏河—塔里木河的连续水体 污染变化曲线,得出污染物浓度随着远离上游而增加。     

Monitoring drought dynamics in the Aravalli region (India) using different indices based on ground and remote sensing data

The hard-rock hilly Aravalli terrain of Rajasthan province of India suffers with frequent drought due to poor and delayed monsoon, abnormally high summer-temperature and insufficient water resources. In the present study, detailed analysis of meteorological and hydrological data of the Aravalli region has been carried out for the years 1984–2003. Standardised Precipitation Index (SPI) has been used to quantify the precipitation deficit. Standardised Water-Level Index (SWI) has been developed to assess ground-water recharge-deficit. Vegetative drought indices like Vegetation Condition Index (VCI) and Temperature Condition Index (TCI) and Vegetation Health Index (VHI) have been computed using NDVI values obtained from Global Vegetation Index (GVI) and thermal channel data of NOAA AVHRR satellite. Detailed analyses of spatial and temporal drought dynamics during monsoon and non-monsoon seasons have been carried out through drought index maps generated in Geographic Information Systems (GIS) environment. Analysis and interpretation of these maps reveal that negative SPI anomalies not always correspond to drought. In the Aravalli region, aquifer-stress shifts its position time to time, and in certain pockets it is more frequent. In comparison to hydrological stress, vegetative stress in the Aravalli region is found to be slower to begin but quicker to withdraw.     

Landslide risk analysis between Giri and Tons Rivers in Himachal Himalaya (India)

The area around Sataun in the Sirmur district of Himachal Pradesh, India (falling between the rivers Giri and Tons; both tributaries of the Yamuna River) was studied for landslide vulnerability on behalf of the inhabitants. The study was made using extensive remote sensing data (satellite and airborne). It is well supported by field evidence, demographic and infrastructural details and aided by Geographic Information System (GIS) based techniques. Field observations testify that slope, aspect, geology, tectonic planes, drainage, and land use all influence landslides in the region. These parameters were taken into consideration using the statistical approach of landslide hazard zonation. Using the census data of 1991, vulnerability of the populace to the landslide hazard was accessed. As most of the infrastructure in the region is concentrated around population centres, population data alone was used for vulnerability studies.     

Gravity Changes Before Large Earthquakes in China: 1998-2005

Although it is well known that coseismic gravity changes take place during an earthquake, previous research has not yielded convincing evidence demonstrating that significant gravity changes occur before large earthquakes. Furthermore, even if we suspect that gravity changes occur before large earthquakes, we have yet to demonstrate how to consistently observe these changes for useful earthquake forecast that would bring benefits to society. We analyzed ground gravity survey data obtained in 1998, 2000, 200...     

GNSS系统及其技术的发展研究

阐述了国际上卫星导航系统的总体发展,对美、俄、欧、中的四大全球系统,以及相关的区域系统和增强系统进行了简单的介绍,研究分析了GNSS系统及其技术的发展趋势,同时分析了我国Compass全球系统面临的机遇和挑战,并提出了我国未来工作的建议.     

“4D”技术及其应用

介绍“４Ｄ”（即数字地面模型、数字正射影像、数字栅格地图和数字线划地图）系列产品的生产流程、关键技术、及其在耕地保护、防灾减灾救灾和城市规划等方面的应用方法。     

Virtual Australia: its key elements – know,think, communicate

Abstract

Virtual Australia is not a well-defined or agreed concept. This discussion paper conceptualises Virtual Australia as a ‘virtual [digital] model containing and representing all non-trivial objects and their contextual environment – from blue sky to bedrock – in real world Australia’. It describes a scenario for Virtual Australia, one or two decades from now, in which the locations and conditions of non-trivial objects and their environment are updated automatically through a combination of remote sensing and wireless communication technologies in support of a ‘Supranet’. It then examines the concept of the ‘Supranet’ – a pervasive information network based largely on wireless technology linking the physical world to a virtual model in real time – and develops and discusses three principal characteristics of the Supranet: the ability to have or collect specific information (know); the ability to process information (think); and the ability to communicate that information. If, in the near future, any or all non-trivial devices are to some extent able to know, think and communicate, the potential for object autonomy will be realised.     

Toward seamless indoor-outdoor applications: Developing stakeholder-oriented location-based services

Location-Based Services (LBS),an emerging new business based on smartphone and mobile networks,are becoming more and more popular.Most of these LBSs,however,only offer non-seamless indoor/outdoor applications and simple applications without giving stakeholders the chance to play an active role.Our specific aim is to solve these issues.This paper presents concepts to solve these issues by expanding the Open Location Services Interface Standard (OpenLS) to allow seamless indoor/outdoor positioning and to extend the content of the services to include information recommended by stakeholders.     

地理数据库的关系模型及其实现

本文从以图论观点分析地理实体入手,系统阐述了地理数据库关系模型的设计法和过程。作者于1984年4～9月间在微型机上设计建立了关系型地理数据库的实方验系统(RGDB)。该系统采用了本文提出的关系模型,采用了可动态扩库的子库组合结构,这种结构具有灵活性和提高空间利用率的优点。RGDB含有多种功能的数据操作命令,除了具有一般检索功能外,还能进行“开窗”选取和十分“自由”的映象选取。本文对RGDB系统的主要性能和实现途径作了扼要介绍。     

GIS空间数据的采集误差及其分析

本文详细阐述了GIS数据采集过程中的误差来源，重点分析了通过地图、遥感和摄影测量等方式采集数据所产生的误差及其特性，分析了其对GIS数据的影响与消减方法。