共查询到20条相似文献，搜索用时 93 毫秒
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地震目录数据动态可视化处理服务系统 总被引：1，自引：0，他引：1
为数据共享项目研制和构建了一个具有一定实用价值的动态地震数据处理及可视化服务的系统, 并简要介绍了该系统的网络编程模式选取, 且选择ISAPI模式作为实现服务平台的编程模式。 详细分析了Internet动态服务平台的设计及实现, 包括服务平台编程语言的选取、 系统的运行环境、 后台的数据库支撑及技术流程等。 通过SQL Server数据库存放和管理用于动态可视化服务的地震目录数据和地震序列目录数据。 在数据库中共存放中国强震目录4227条和中国小震目录188033条以及7个地震序列目录共计50072条。 最后, 着重介绍了该服务系统的主要功能, 包括地震目录服务功能和地震序列分析处理功能。 相似文献
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用ASP.NET和C#动态绘制WEB震中分布图的一种方法 总被引：1，自引：1，他引：0
李志雄 《地震地磁观测与研究》2004,25(1):83-87
简述了NET、ASP．NET的特性及绘制图形的基本原理,介绍在地震目录查询服务中采用ASP．NET与C#,实现通过网页动态绘制地震震中分布图的一种方法。 相似文献
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介绍一种B/S架构下测震实时波形可视化方法,能够自动侦测Jopens数据库中数据,并解压缩测震waveform数据表的连续波形数据,将数据以字符串形式进行存储。通过应用fusionchart实现动态实时展示。在实时地震波形的移植性上推进一步,为地震数据的展示与对外界的服务奠定了基础。 相似文献
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基于实时技术和3D WebGIS的地震信息发布系统 总被引：1，自引：1，他引：0
《地震地磁观测与研究》2016,(1)
随着社会对地震信息服务提出更高要求,现有地震信息系统(基于GIS)动态数据处理能力不足,地震信息表达与真实三维环境表达存在一定差距,结合实时技术和GIS,设计和实现基于三维Web GIS的地震综合发布信息系统。该系统改进GIS对动态地震信息的处理模式,利用三维可视化技术表征动态地震信息,为地震信息服务提供一种快速、直观形象表达地震综合信息的方法,在大地震震情分析应用中发挥了重要作用。 相似文献
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地震行业网域名服务系统采用BIND9软件,并利用该软件的最新视图功能,根据客户端源地址的不同,分别做出解析。本文简要介绍了域名系统的结构和工作原理,并以《中国地震信息服务系统技术规程》为依据,描述了地震行业网域名服务系统。同时以国家中心（中国地震台网中心）为例,对视图功能进行了介绍并给出了配置示例,指出了运行中应该注意的问题。 相似文献
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介绍了基于Internet/Intranet标准的爆破等特殊波形数据管理与服务系统(EMASS系统)的各个组成部分及各部分的实现。该实现方案采用Windows 2003 Server,IIS6.0平台,利用ASP.NET技术和脚本语言Java Script,Vb Script及HTML技术,响应浏览器端的动态请求,实现诸如数据管理、数据服务功能,并根据用户请求完成波形数据的下载。 相似文献
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Wm. Alexander Osborne Rebecca A. Hodge Gordon D. Love Peter Hawkin Ruth E. Hawkin 《地球表面变化过程与地形》2021,46(13):2656-2670
The passive, ambient sound above the water from a river has previously untapped potential for determining flow characteristics such as stage. Measuring sub-aerial sound could provide a new, efficient way to continuously monitor river stage, without the need for in-stream infrastructure. Previous published work has suggested that there might be a relationship between sound and river stage, but the analysis has been restricted to a narrow range of flow conditions and river morphologies. We present a method to determine site suitability and the process of how to record and analyse sound. Data collected along a 500 m length of the River Washburn during July 2019 is used to determine what makes a site suitable for sound monitoring. We found that sound is controlled by roughness elements in the channel, such as a boulder or weir, which influences the sound produced. On the basis of these findings, we collect audio recordings from six sites around the northeast of England, covering a range of flow conditions and different roughness elements, since 2019. We use data from those sites collected during storms Ciara and Dennis to produce a relationship between this sound and river stage. Our analysis has shown a positive relationship between an R2 of 0.73 and 0.99 in all rivers, but requires careful site selection and data processing to achieve the best results. We introduce a filter that is capable of isolating a river's sound from other environmental sound. Future work in examining the role of these roughness elements is required to understand the full extent of this technique. By demonstrating that sound can operate as a hydrometric tool, we suggest that sound monitoring could be used to provide cost-effective monitoring devices, either to detect relative change in a river or, after more research, a reliable stage measurement. 相似文献
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Maiclaire K. Bolton Dmitry A. Storchak James Harris 《Physics of the Earth and Planetary Interiors》2006,158(1):27-45
The International Seismological Centre (ISC) publishes the definitive global bulletin of earthquake locations. In the ISC bulletin, we aim to obtain a free depth, but often this is not possible. Subsequently, the first option is to obtain a depth derived from depth phases. If depth phases are not available, we then use the reported depth from a reputable local agency. Finally, as a last resort, we set a default depth.In the past, common depths of 10, 33, or multiples of 50 km have been assigned. Assigning a more meaningful default depth, specific to a seismic region will increase the consistency of earthquake locations within the ISC bulletin and allow the ISC to publish better positions and magnitude estimates. It will also improve the association of reported secondary arrivals to corresponding seismic events.We aim to produce a global set of default depths, based on a typical depth for each area, from well-constrained events in the ISC bulletin or where depth could be constrained using a consistent set of depth phase arrivals provided by a number of different reporters.In certain areas, we must resort to using other assumptions. For these cases, we use a global crustal model (Crust2.0) to set default depths to half the thickness of the crust. 相似文献
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T. V. Hromodka II R. J. Whitley 《Stochastic Environmental Research and Risk Assessment (SERRA)》1994,8(4):259-268
In this paper a very general rainfall-runoff model structure (described below) is shown to reduce to a unit hydrograph model structure. For the general model, a multi-linear unit hydrograph approach is used to develop subarea runoff, and is coupled to a multi-linear channel flow routing method to develop a link-node rainfall-runoff model network. The spatial and temporal rainfall distribution over the catchment is probabilistically related to a known rainfall data source located in the catchment in order to account for the stochastic nature of rainfall with respect to the rain gauge measured data. The resulting link node model structure is a series of stochastic integral equations, one equation for each subarea. A cumulative stochastic integral equation is developed as a sum of the above series, and includes the complete spatial and temporal variabilities of the rainfall over the catchment. The resulting stochastic integral equation is seen to be an extension of the well-known single area unit hydrograph method, except that the model output of a runoff hydrograph is a distribution of outcomes (or realizations) when applied to problems involving prediction of storm runoff; that is, the model output is a set of probable runoff hydrographs, each outcome being the results of calibration to a known storm event. 相似文献
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In this paper a very general rainfall-runoff model structure (described below) is shown to reduce to a unit hydrograph model structure. For the general model, a multi-linear unit hydrograph approach is used to develop subarea runoff, and is coupled to a multi-linear channel flow routing method to develop a link-node rainfall-runoff model network. The spatial and temporal rainfall distribution over the catchment is probabilistically related to a known rainfall data source located in the catchment in order to account for the stochastic nature of rainfall with respect to the rain gauge measured data. The resulting link node model structure is a series of stochastic integral equations, one equation for each subarea. A cumulative stochastic integral equation is developed as a sum of the above series, and includes the complete spatial and temporal variabilities of the rainfall over the catchment. The resulting stochastic integral equation is seen to be an extension of the well-known single area unit hydrograph method, except that the model output of a runoff hydrograph is a distribution of outcomes (or realizations) when applied to problems involving prediction of storm runoff; that is, the model output is a set of probable runoff hydrographs, each outcome being the results of calibration to a known storm event. 相似文献
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PETER HUTCHINSON 《水文科学杂志》2013,58(1):101-103
Synopsis In areas of accentuated relief, some of the basic assumptions made in the use of standard methods of assessing areal mean rainfall are often untenable. It is shown in this paper, that, not only does topography affect the actual rainfall distribution, but that the areal variability, measured as the correlation between any two points, is also dependent on the relief. Two methods are used to show this. Once method compares the areal variability of a flat area to one of accentuated relief, while the second method relates areal variability to topographic factors using a multiple regression technique. The conclusions reached are then used for three purposed. The first is to develop a method of ascribing objectively areas or points to a particular raingauge, taking into account the nature of the terrain. The second is to establish a procedure for estimating the rainfall at ungauged points, by taking into account the rainfall at a selected nearby rainguage and the topographic situation of the points, and the third purpose is to provide means of establishing a correction factor to be applied to a raingauge reading in order that the reading may more accurately represent the area ascribed to it. 相似文献
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H.F. Aristizábal 《水文科学杂志》2019,64(8):885-899
Wetlands are vulnerable to groundwater extraction, which has proven detrimental to aquatic ecosystems around the planet. As wetlands rank among the world’s most endangered ecosystems, versatile strategies are required to protect them. This paper provides a modelling-based method to delineate protection buffers in wetlands subject to groundwater extraction. The technique is sufficiently flexible to cater to a wide variety of conditions, and simple enough to underpin management decisions on a daily basis. A numerical model is used to obtain a map of the critical rate of groundwater abstraction, based on the distance between wetlands and suitable discharge thresholds. The outcomes determine the allowed pumping rate at any point under steady and transient-state conditions. A new iteration is developed every time a new pumping allowance is made. This procedure is demonstrated by means of hypothetical scenarios, as well as by a case study application in the Valle del Cauca region, Colombia. 相似文献
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Morphodynamic assessment of side channel systems using a simple one‐dimensional bifurcation model and a comparison with aerial images 
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下载免费PDF全文 R. Pepijn van Denderen Ralph M. J. Schielen Astrid Blom Suzanne J. M. H. Hulscher Maarten G. Kleinhans 《地球表面变化过程与地形》2018,43(6):1169-1182
Side channel construction is a common intervention applied to increase a river's conveyance capacity and to increase its ecological value. Past modelling efforts suggest two mechanisms affecting the morphodynamic change of a side channel: (1) a difference in channel slope between the side channel and the main channel and (2) bend flow just upstream of the bifurcation. The objective of this paper was to assess the conditions under which side channels generally aggrade or degrade and to assess the characteristic timescales of the associated morphological change. We use a one‐dimensional bifurcation model to predict the development of side channel systems and the characteristic timescale for a wide range of conditions. We then compare these results to multitemporal aerial images of four side channel systems. We consider the following mechanisms at the bifurcation to be important for side channel development: sediment diversion due to the bifurcation angle, sediment diversion due to the transverse bed slope, partitioning of suspended load, mixed sediment processes such as sorting at the bifurcation, bank erosion, deposition due to vegetation, and floodplain sedimentation. There are limitations to using a one‐dimensional numerical model as it can only account for these mechanisms in a parametrized manner, but the model reproduces general behaviour of the natural side channels until floodplain‐forming processes become important. The main result is a set of stability diagrams with key model parameters that can be used to assess the development of a side channel system and the associated timescale, which will aid in the future design and maintenance of side channel systems. © 2017 The Authors. Earth Surface Processes and Landforms published by John Wiley & Sons Ltd. 相似文献
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This paper gives a synthesis on a series of studies demonstrating the possibility to have a direct access to in situ soil damping, exploiting the thermal dissipation due to irreversible mechanical phenomena under severe seismic conditions. The introduction provides a background to the three steps of such a study: instrumentation, modelling and inverse identification problem. Section 2 recalls the principle of the Seismic Harmonic System, equipment able to generate powerful in situ soil accelerations in the vicinity of a well. Evidence of a significant in situ soil temperature elevation is given under such seismic conditions. Section 3 reviews the mechanical and related thermal simulations for the prediction by a direct problem procedure of the mean temperature elevation in the vicinity of the borehole, using a two- or three-parameter behaviour model depending on the intensity of the actions. Section 4 is a synthesis of the possibilities offered by thermal in situ measurements to contribute, in parallel with mechanical measurements, to the identification and/or the validation of the damping characteristics of an in situ soil. 相似文献
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The rheology of debris flows is difficult to characterize owing to the varied composition and to the uneven distribution of the components that may range from clay to large boulders, in addition to water. Few studies have addressed debris flow rheology from observational, experimental, and theoretical viewpoints in conjunction. We present a coupled rheological‐numerical model to characterize the debris flows in which cohesive and frictional materials are both present. As a first step, we consider small‐scale artificial debris flows in a flume with variable percentages of clay versus sand, and measure separately the rheological properties of sand–clay mixtures. A comparison with the predictions of a modified version of the numerical model BING shows a reasonable agreement between measurements and simulations. As application to a field case, we analyse a recent debris flow that occurred in Fjærland (Western Norway) for which much information is now available. The event was caused by a glacial lake outburst flood (GLOF) originating from the failure of a moraine ridge. In a previous contribution (Breien et al., Landslides, 2008 , 5: 271–280) we focused on the hydrological and geomorphological aspects. In particular we documented the marked erosion and reported the change in sediment transport during the event. In contrast to the laboratory debris flows, the presence of large boulders and the higher normal pressure inside the natural debris flow requires the introduction of a novel rheological model that distinguishes between mud‐to–clast supported material. We present simulations with a modified BING model with the new cohesive‐frictional rheology. To account for the severe erosion operated by the debris flow on the colluvial deposits of Fjærland, we also suggest a simple model for erosion and bulking along the slope path. Numerical simulations suggest that a self‐sustaining mechanism could partly explain the extreme growth of debris flows running on a soft terrain. 相似文献