河口地区遥感信息系统设计开发与应用

采用先进的3S、数据库管理、计算机等技术构建海河口等四河口遥感信息系统,实现地图上元素的水政专题、遥感、空间等信息的集成显示,对四河口地区信息的调用、浏览、查询等综合管理,动态变化情况的对比分析,以及分析成果的存储与输出等工作,准确地掌握河口地区岸线变化、项目建设进展情况,同时配合实地调查取证,为水政监察工作提供充分的执法依据,有效提高四河口水行政执法监管水平。     

咸潮入侵预警预报信息系统的设计与仿真

研究咸潮入侵实时、准确预警预报问题.目前咸潮入侵多为实测数据,没有相应的预警预报系统,无法实时、准确地预警咸情.为解决上述问题,提出可变河口盐度仿真迭代预警模型并给出实现算法.只要获取河口盐度和径流量等几个参数就能快速准确预警当地咸潮入侵盐度和入侵距离,解决了当地咸潮入侵预警预报实时性和准确性的技术难题.经过仿真证明.可变河口盐度模拟迭代预警算法误差较小,能快速、准确地监测预警咸潮入侵情况;基于算法开发设计的咸潮入侵预警预报信息系统在线预警形式直观,实现了珠三角地区成情的实时、准确预警,证明了预报系统的有效性.     

资源一号卫星IR—MSS数据在洪泽湖地区的应用研究评价

对资源一号卫星IR－MSS数据从空间分辨率、几何精度、噪声等方面做了分析评价。选取了典型的洪泽湖地区作为研究区,对经过几何精纠正的IR－MSS数据进行了不同地物在不同波段上的光谱采样分析。进行了湖泊信息提取实验,提取效果较好。最后对洪泽湖的形态特征、环境因素、动态变迁等方面做了分析研究,从图像上可清晰地看出洪泽湖河口淤积、岸边污染的情况。     

模糊信息优化处理技术应用简介

本文介绍了模糊信息优化处理技术在人工神经网络、大地测量数据处理、风险分析、评估体系等四个方面的应用情况,并对该领域在基础理论、实用方法、商业应用等三个方面的发展进行了简短的讨论.     

OICQ的攻击与预防

文章主要介绍了OICQ采用的UDP协议在网络安全性上缺陷,分析了轰炸他人帐号、信息保存不安全、密码破解及发送捆绑“木马”文件四种攻击方法,提出了安装个防火墙、使用QICQ防护工具、隐藏自身IP地址等预防措施。     

OICQ的攻击与预防

文章主要介绍了OICQ采用的UDP协议在网络安全性上的缺陷,分析了轰炸他人帐号、信息保存不安全、密码破解及发送捆绑"木马"文件四种攻击方法,提出了安装个人防火墙、使用OICQ防护工具、隐藏自身IP地址等预防措施.     

福建省专利信息服务平台体系设计

福建省专利信息服务平台是近几年福建省专利信息工作的重要成果,它包括了专利数据源、专利数据服务系统、专利信息中间件、专利信息应用平台等四个功能层,具备了专利检索、分析、预警、聚类等功能,智能化专利信息应用,并通过将常用的功能组件化、通用化,提高了平台的可扩展性,为福建省专利信息服务的开展打好了基础。     

四班三运转生产模式下自动换班程序的实现

我国企业现在有很多采用四班三运转的生产模式,探讨了在此模式下,集控数据采集中班次自动更换的一种实现方式。该方式以数据库和监控程序相结合,实现了换班时间自动提取下一班次信息。在正常班次轮转时,不需人为干预。在遇到企业停产歇班等情况时,只需上第一个班的班次确定一下基本信息即可保证换班程序的正常运转。     

军事信息发布系统安全防护体系研究

本文提出了军事信息发布系统六层安全防护体系,对安全操作系统层、数据库系统层、网络传输层和应用层等四个技术层面进行了详细地阐述,在应用层设计并实现了军事信息发布系统接入全军安全认证系统,从而完成了军事信息发布系统在多层面上的一体化安全防护。     

RMON的配置与应用研究

目前，支持RMON的网络设备一般都支持RMONMIB中的统计、历史、告警、事件等四个组，但在实际的网络管理中，一般很少有人去使用RMONMIB信息。通过网络设备对RMON的支持情况的调查，给出了在交换机上实现RMON中功能的配置方法，并在实际的网络管理中得到应用。     

Remote sensing monitoring of ocean colour in Pearl River estuary

The study attempts to provide additional understanding of the long-term evolution of water quality in the Pearl River estuary and Hong Kong coastal areas by monitoring the ocean colour from remote sensing images. The extensively inter-connected river network of Pearl River estuary has a large catchment area and its environmental deterioration due to rapid economic growth is significant. The data received by Landsat satellites, over a time period of more than 20 years, were used to evaluate the evolution of water clarity. The study shows the historical varying of sea colour in these areas and image processing methods for extracting the ocean colour features of Landsat images are suggested. The algorithm of 'Gradient Transition' was used to calibrate the result images and the comparing method was used to process and analyse remote sensing images of Case 2 water.     

The application of remote sensing data in the study of effluent dispersal in the Tay estuary,Scotland

The results of a remote sensing study have been correlated with previous research on estuarine mixing processes and with ground sampling investigations to appraise the dispersal of effluent in the Tay estuary. The advantages of using remote sensing techniques to study the distribution of convergent fronts and their effect on the dispersal of effluent are demonstrated. The application of remote sensing data in the study of the near-shore dispersion from outfalls and the short-term dispersal behaviour of outfalls are discussed with reference to two particular sewer outfalls. The results of the remote sensing studies correlate highly with ground studies of the same areas. A modified simulation model of the flushing capacity of the Tay estuary has been developed incorporating the results of the remote sensing study. The results of the model are very similar to those calculated from a physical model. The preliminary results of a study to integrate urban hydrological and outfall dispersal models with remote sensing data are reviewed.     

The application of remotely sensed data in the study of frontal systems in the Tay Estuary,Scotland, U.K.

The results of a remote sensing study of tidal mixing processes in the Tay estuary are correlated with the results of mathematical and physical models and ground sampling data in an attempt to assess the nature, the spatial and temporal extent, and the variability in the formation of convergent fronts in the Tay estuary. The application of remote sensing methods to the study of estuarine mixing processes in the Tay Estuary, supported by ground measurements, reveal convergent front mechanisms which had not previously been recognized in the Tay estuary. This integrated approach enables the various features and mixing mechanisms found in the lower section of the estuary to be related. The limitations of using a two-dimensional mathematical and a physical model to predict the complex mixing processes affecting water quality in the Tay Estuary are discussed. The widespread occurrence of convergent systems in the estuarine environment suggests that to obtain an accurate estuarine water quality model, the effect of fronts should be included. The limitations of remote sensing data, the problems of geometrically rectifying airborne imagery in the coastal zone, and two methods of correcting for atmospheric effects in the thermal infrared waveband are also discussed.     

基于SPOT影像的水体信息提取以及在湿地分类中的应用研究

利用SPOT影像数据,对研究区进行遥感图像融合处理实验,探讨了基于SPOT影像的水体信息提取的方法,以及在湿地分类中的应用。     

Comparison of ANN approach with 2D and 3D hydrodynamic models for simulating estuary water stage

Accurately predicting tidal levels, including tidal and freshwater discharge effects, is important for human activities in estuaries. The traditional harmonic analysis method and numerical modeling are usually adopted to simulate and predict estuary water stages. This study applied artificial neural networks (ANNs) as an alternative modeling approach to simulate the water stage time-series of the Danshui River estuary in northern Taiwan. We compared this approach with vertical (laterally averaged) 2D and 3D hydrodynamic models. Five ANN models were constructed to simulate the water stage time-series at the Shizi Tou, Taipei Bridge, Rukuoyan, Xinhai Bridge, and Zhongzheng Bridge locations along the Danshui River estuary. ANN models can preserve nonlinear characteristics between input and output variables and are superior to physical-based hydrodynamic models during the training phase. The simulated results reveal that the vertical 2D and 3D hydrodynamic models could not capture the observed water stages during an input of high freshwater discharge from upstream boundaries, while the ANN could match the observed water stage. However, during the testing phase, the ANN approach was slightly inferior to the 2D and 3D models at the Xinhai Bridge, Zhongzheng Bridge, and Rukouyan locations. Our results show that the ANN was able to predict the water stage time-series with reasonable accuracy, suggesting that ANNs can be a valuable tool for estuarine management.     

Modelling of pH and inorganic carbon speciation in estuaries using the composition of the river and seawater end members

An equilibrium model based on the CO₂ system was developed to model pH throughout the estuarine salinity range using the composition of the river and seawater end members. In order to validate the model, a spectrophotometric method was used to measure pH in an estuary and laboratory mixing experiments. The model successfully represented the measured pH values (±0.1 pH units) for three different river water end member compositions. The pH decreased at low salinities (S ≈ 0–2), increased at intermediate salinities (S ≈ 2–15), and then stabilised for higher salinity values. Changes in the inorganic carbon speciation in the low salinity region of estuaries result in assimilation of river borne CO_2(aq).     

Numerical simulation-aided MODIS capture of sediment transport for the Bohai Sea in China

Traditionally, the establishment of a remote-sensing retrieval model depends on in situ data acquired by expensive and considerably labour-intensive field surveys, but now we can benefit from numerical simulation. In this study, after considering the advantages of numerical simulation in extending the spatial and temporal suspended sediment concentration (SSC), we propose an approach to establish an SSC retrieval model from remotely sensed images with the aid of a numerical model for the Bohai Sea in China. First, significant correlation, between simulated SSC and atmosphere-corrected water-leaving reflectance derived from Moderate Resolution Imaging Spectroradiometer (MODIS) band-1 images, was investigated to demonstrate a novel SSC retrieval model. The synchronous data from remote sensing and numerical simulations enabled the removal of spatial and temporal differences between satellite and in situ measurements. Based on this retrieval model, the SSC distribution pattern was simulated in two scenarios to separate river sediment discharge from the overall process of resuspension. The results indicate that the distribution pattern of the simulated surface SSC without sediment discharge from the Yellow River in most study areas generally matched that derived from MODIS images, except for the estuarine area. The surface SSC 30–40 km away from the estuaries are dominated by sediment discharge from rivers. The proposed method, the numerical simulation-aided SSC retrieval MODIS model, can efficiently capture the sediment transport in the Bohai Sea, which is helpful for operational monitoring of the water environment in estuary and coastal waters.     

Modelling the effects of reservoir construction on tidal hydrodynamics and suspended sediment distribution in Danshuei River estuary

A vertical (laterally integrated) two-dimensional numerical model was implemented to study the hydrodynamics, saltwater intrusion, and suspended sediment in the Danshuei River–Tahan Stream due to the Shihmen Reservoir construction in the upriver reaches. The construction of the reservoir and water diversion in the upper reaches of the river system significantly reduces the freshwater inflow and drastically changes the river bathymetry. The model was calibrated and verified with the available hydrographic data measured in 1977, 1978, and 1999 as well as measured salinity and suspended sediment concentration in 1999. The overall performance of the model is in reasonable agreement with the field data. The validated model was then used to investigate the change in hydrodynamics, saltwater intrusion, suspended sediment distribution, and flushing time as a result of reservoir construction in upper river of Tahan Stream. The model simulations indicate that more tidal energy propagates into the estuarine system after reservoir construction because of the substantial increase in river cross-sections. The limits of saltwater intrusion after reservoir construction extended farther inland 2–3 km than those after reservoir construction. The modelling results also reveal that the suspended sediment concentration before reservoir construction was higher than that after reservoir construction along the river mouth to Kuan-Du due to the significant bathymetric change after the reservoir construction. The calculated estuary flushing time was strongly dependent on river flow and reduced 2.3–25 h under different river discharges after reservoir construction due to the change in river bathymetry.     

黄河下游河势遥感监测系统建设分析

为提高黄河下游河势遥感监测能力,提升河势遥感监测服务水平,深入探讨黄河下游河势遥感监测的现状和存在的问题,提出黄河下游河势遥感监测系统的建设目标及思路。通过充分整合卫星遥感、黄河水利对象等相关数据,最大程度地共享现有数据资料和软硬件资源,设计开发黄河下游河势遥感监测系统,包括卫星遥感数据传输通道建设、遥感数据处理软硬件和存储设施建设、河势信息解译和服务功能开发,以及河势信息数据库建设等。结果表明：黄河下游河势遥感监测系统的建设可强化黄河河势遥感监测的数据计算与存储服务能力,提升河势信息解译的自动化水平,实现河势遥感监测工作的数字化及河势信息服务的高效化,具有很好的推广应用前景。     

An integrated modelling system for management of the Patuxent River estuary and basin,Maryland, USA

The Patuxent River watershed is a heavily impacted basin (2290 km²) and estuarine tributary (120 km²) of the Chesapeake Bay, USA. To assist management of the basin, we are testing a coupled modelling system composed of a watershed model (HSPF), an estuarine circulation model (CH3D), and an estuarine water‐quality model (CE‐QUAL‐ICM). The modelling system is being tested to guide the development of Total Maximum Daily Loads (TMDLs), and therefore errors in the models must be carefully evaluated. A comparison of daily total nitrogen (TN) concentrations simulated in HSPF with observations indicated that there was no significant bias, with an rms error of 37%. In contrast, modelled total phosphorus (TP) and total suspended solids (TSS) had significant bias with larger rms errors (65% and 259%, respectively). In the estuary, CH3D accurately simulated tides, temperature, and salinity. CE‐QUAL‐ICM overestimated nitrogen (N) and phosphorus (P) in the upper estuary and underestimated in the lower estuary, primarily because intertidal marshes are not currently a model component. Model errors declined from short (1 day) to long (multi‐year) timescales as under‐ and overestimations cumulatively cancelled. Watershed model errors propagate into the estuarine models, interacting with each subsequent model's errors, which limits the effectiveness of this TMDL management tool at short timescales.