Analysis of bedload transport characteristics of Idaho streams and rivers

Field data are essential in evaluating the adequacy of predictive equations for sediment transport. Each dataset based on the sediment transport rates and other relevant information gives an increased understanding and improved quantification of different factors influencing the sediment transport regime in the specific environment. Data collected for 33 sites on 31 mountain streams and rivers in Central Idaho have enabled the analysis of sediment transport characteristics in streams and rivers with different geological, topographic, morphological, hydrological, hydraulic, and sedimentological characteristics. All of these streams and rivers have armored, poorly sorted bed material with the median particle size of surface layer coarser than the subsurface layer. The fact that the largest particles in the bedload samples did not exceed the median particle size of the bed surface material indicates that the armor layer is stable for the observed flow discharges (generally bankfull or less, and in some cases two times higher than bankfull discharge). The bedload transport is size‐selective. The transport rates are generally low, since sediment supply is less than the ability of flow to move the sediment for one range of flow discharges, or, the hydraulic ability of the stream is insufficient for entrainment of the coarse bed material. Detailed analyses of bedload transport rates, bedload and bed material characteristics were performed for each site. The obtained results and conclusions are used to identify different influences on bedload transport rates in analyzed gravel‐bed rivers. Copyright © 2008 John Wiley & Sons, Ltd.     

The new worldwide collapse caldera database (CCDB): A tool for studying and understanding caldera processes

Collapse calderas are one of the most important volcanic structures not only because of their hazard implications, but also because of their high geothermal energy potential and their association with mineral deposits of economic interest. The objective of this work is to describe a new general worldwide Collapse Caldera DataBase (CCDB), in order to provide a useful and accessible tool for studying and understanding caldera collapse processes. The principal aim of the CCDB is to update the current field based knowledge on calderas, merging together the existing databases and complementing them with new examples found in the bibliography, and leaving it open for the incorporation of new data from future studies. This database does not include all the calderas of the world, but it tries to be representative enough to promote further studies and analyses. We have performed a comprehensive compilation of published field studies of collapse calderas including more than 200 references, and their information has been summarized in a database linked to a Geographical Information System (GIS) application. Thus, it is possible to visualize the selected calderas on a world map and to filter them according to different features recorded in the database (e.g. age, structure). The information recorded in the CCDB can be grouped in seven main information classes: caldera features, properties of the caldera-forming deposits, magmatic system, geodynamic setting, pre-caldera volcanism, caldera-forming eruption sequence and post-caldera activity. Additionally, we have added two extra classes. The first records the references consulted for each caldera. The second allows users to introduce comments on the caldera sample such as possible controversies concerning the caldera origin. A further purpose of this work is to construct the CCDB web page. In this web page where registered users can acquire the current database version, as well as to propose corrections or updates and to exchange information with other registered members also involved in the study of caldera collapse processes. Additionally, the CCDB includes a formulary that will facilitate the incorporation of new calderas into the database.     

辽宁省地震应急基础数据库建设

本文介绍了地震应急基础数据库的总体功能,数据资料的收集与处理过程,各类属性图的建立、地图的制作等。最后给出了基础数据库在地震应急响应系统中的使用结果。     

<省级航磁数据库>航磁模拟资料数字化方法

建立“省级航磁数据库”是地调局下达的项目,为保证提供合格的建库数据,针对大量存在的航磁模拟资料,航空物探遥感中心通过试验总结,提出了在航磁ΔＴ剖面厘米底图上,采用数字化仪进行数字化的方法、流程和质量检查要求,完成了航空物探遥感中心拥有的１３８个测区的航磁模拟资料数字化工作,取得了全国绝大多数地区的入库航磁数据。同时该方法已向有关地勘单位推广使用。     

模糊关系数据库中数据的特点和完整性研究

从模糊集合的基本理论出发,分析了模糊关系数据库的数据特点,给出了模糊关系的形式化描述,对由于模糊关系将传统关系的范围由二值逻辑论扩展到模糊集合论而引起的问题进行了探讨,特别对模糊数据库数据的完整性作了较深入的研究。     

一种气候分析服务系统的研制与开发

简要介绍一种采用ＦｏｘＰｒｏ Ｆｏｒ Ｗｉｎｄｏｗｓ语言设计的适用于省级气候中心的“气候分析服务系统”。该系统将数据库管理、气候诊断与评价、气候预警和灾情分析有机结合为一个系统,既可提供各种分析结果的数据,又可自动生成各种分析结果的图形、报表和文字公报。界面美观,使用方便,库管理和图形处理功能较强,系统具有开放性,灵活性和可扩充性,与国内同类系统的设计相比有一定的特色和先进性。     

地质数据仓库设计中的几个问题

提出并讨论了地质数据仓库系统设计中的几个问题：操作数据存储作 和数据仓库间的数据接口,借用地理信息系统来存储和表示空间数据,级联式更新、主题间复杂交系的表达,以及专用的数据抽取模型的设计。     

Automatic searching of control point in NOAA AVHRR image

This paper discusses the approaches for automatical searching of control points in the NOAA AVHRR image on the basis of data rearrangement in the form of latitude and longitude grid. The vegetation index transformation and multi-level matching strategies have been proven effective and successful as the experiments show while the control point database is established.     

GPS与路线CAD数据的交换及应用

ＧＰＳ全球定位系统在公路勘测设计中已得到较为广泛的应用, 特别是实时动态ＲＴＫ 技术在测设中线方面的成功应用, 突破了常规红外测距仪或全站仪测设中线的方法。本文作者论述运用路线ＣＡＤ 程序和Ｗｏｒｋ Ｂｅｎｃｈ 软件相结合, 实现ＧＰＳ数据与路线ＣＡＤ 数据之间的传输交换, 并在周口至界首高速公路测量中得到成功地应用。     

铀矿三维可视化技术与实现

针对广东省已建成的铀矿钻孔数据库系统在工程地质分析、解释全过程方面未能实现数字化可视化分析的空间管理问题,该文提出以地理信息系统平台为基础,根据铀矿成矿、勘探、储量估算的特点,建设三维铀矿建模地理信息系统平台。实现了铀矿勘查数据库建库、矿区地质成图、矿体圈定、矿床地质建模、品位估计和储量估算等全过程的数字化、可视化的查询与分析;结合地表建模及可叠加遥感技术,实现了地上地下全方位矿区立体建模。实践表明,利用该系统重构的地质矿体真实可靠,与传统解释方法基本一致,符合铀矿成矿原理。