用于热门路径查询的动态热度路网的构建方法

基于位置的服务在蓬勃发展的同时,产生出大量的用户位置轨迹数据,同时基于轨迹数据的热门路径问题也越来越受到人们的重视。对于求解点到点热门路径的问题,一张带有动态热度信息的热度路网是非常必要的。首先,提出了一个高效的交叉口生成算法,用于构建静态的热度路网,并在此基础上提出一种新的时间段分割算法来使得路网中对应热度边动态化。采用希腊雅典的一部分卡车的GPS轨迹数据集,通过大量充分的实验,印证了算法的合理性和高效性。     

基于RBF网络的地下水动态模拟与预测

准确地预测地下水位对人民生活、生产都有很重要的意义.针对地下水位是一个与多种因素相关的复杂的非线性问题,利用RBF(Radial Basis Function)神经网络自适应确定、输出与初始权值无关等优良特性,将该网络应用于某地下水动态模拟与预测,演示训练样本集与检测样本集的构建、原始数据的预处理、神经网络的构建训练和检测及结果评价的整个过程.并且通过仿真确定了最佳的径向基函数的分布spread,达到了很好的预测效果.     

岩溶区某铝土矿排泥库防渗漏综合治理概述

防渗漏治理是一项复杂的系统工程,是排泥库安全运行的关键,以桂西某堆积型铝土矿排泥库为例,参照类似工程中的防渗漏治理经验,针对其库址周边水力流向、断层性质及岩溶发育、分布情况,提出了一套完善的防渗漏治理方案,包括溶洞治理、断层处理及库区边坡处理、库底处理等,最后总结了排泥库防渗漏治理的几点基本原则,为排泥库建设提供了新思路、新方法。     

有限元离散模型在化工区地下水污染预测中的应用

随着我国经济的不断发展,工业生产对环境污染影响越来越严重,一些不正当的人类活动引起的水污染也日益严重,近年来我国频繁发生水资源污染事件,为了更好的进行环境保护处理,利用有限元离散模型对化工区地下水污染预测中的应用方法进行了研究.对水环境质量评价算法进行优化,实现对地下水污染进行精准预测,科学管理规划实施和水污染防治方法...     

TEMPORAL AND SPATIAL DISCRETIZATION ON QUASI-3-D GROUNDWATER FINITE ELEMENT MODELLING TO AVOID SPURIOUS OSCILLATION

In this article, the finite element solution of quasi-three-dimensional (quasi-3-D) groundwater flow was mathematically analyzed. The research shows that the spurious oscillation solution to the Finite Element Model (FEM) is the results choosing the small time step ?t or the large element size L and using the non-diagonal storage matrix. The mechanism for this phenomenon is explained by the negative weighting factor of implicit part in the discretized equations. To avoid spurious oscillation solution, the criteria on the selection of ?t and L for quasi-3-D groundwater flow simulations were identified. An application example of quasi-3-D groundwater flow simulation was presented to verify the criteria. The results indicate that temporal discretization scale has significant impact on the spurious oscillations in the finite-element solutions, and the spurious oscillations can be avoided in solving practical quasi-3-D groundwater flow problems if the criteria are satisfied.     

Influence of Seepage Face Obliquity on Discharge of Groundwater and its Pollutant into Lake from A Typical Unconfined Aquifer

Lab experiment and mathematical simulation Modular three dimensional finite difference groundwater (MODFLOW) were performed in a soil tank to simulate the hydrogeochemical interaction between lake and typical unconfined aquifer. Results show that the velocity decreases exponentially with the transect distance on seepage face. The maximal velocity occurs at the top point of seepage face. The obliquity of seepage face has a great influence on the maximum and distribution of seepage velocity. With the increase of the obliquity of seepage face, the maximal velocity decreases quickly and the velocity distribution becomes much more even. Most of groundwater flow and pollutant flux discharges through a narrow portion near the top of seepage face. The flow and mass concentrated in the narrow portion increase with the decrease of the obliquity of seepage face. These will benefit to design a reasonable and economical scenario to manage lakeshore and to control the pollution of lake water near lakeshore.     

基坑变形监测与事故原因分析

通过对沈阳万科首开一期基坑、沈阳万科四季花城基坑、中旅万科城四期基坑、沈阳阳光100基坑、美的基坑等的变形监测,根据变形监测数据,分析事故及险情发生的原因,进一步为设计和施工停供数据和建议支撑.     

喀什噶尔河流域地下水功能区划分研究

为对喀什噶尔河流域地下水资源进行合理开发利用和保护,基于现行的《全国地下水功能区划分技术大纲》内容,对流域内生态环境保护、地下水资源开发以及地下水系统特征等方面进行了全面分析,因水制宜地划分了各级功能区,同时密切结合流域内地下水超采问题对不同功能区分别提出了具体保护目标,对地下水保护和利用及超采区治理提供参考。     

粤东沿海韩江下游流域地下水分析

该文从地形地貌、地质构造、地下水特征、地下水化学等方面分析了粤东沿海韩江下游流域的地下水特性,并分析计算了该地区的地下水资源量,可为开采利用其地下水资源提供参考。