GM(1,1)模型的遗传算法优化及效果检验

对平稳的数据和非平稳数据两种数据序列建立的GM（1，1）模型，分别用加速遗传算法（AGA）和最小二乘法（LSM）对模型参数求解。结果表明：对平稳变化数据序列，两种方法建立的预测模型的拟合优度和预测精度无显著差异；对变化幅度较大的非平稳数据序列，基于AGA的GM（1，1）模型的拟合优度和预测精度高于基于LSM的GM（1，1）模型的拟合优度和预测精度。     

Hydraulic Effects of Shales in Fluvial-Deltaic Deposits: Ground-Penetrating Radar, Outcrop Observations, Geostatistics, and Three-Dimensional Flow Modeling for the Ferron Sandstone, Utah

Ground-penetrating radar (GPR) surveys, outcrop measurements, and cores provide a high-resolution 3D geologic model to investigate the hydraulic effects of shales in marine-influenced lower delta-plain distributary channel deposits within the Cretaceous-age Ferron Sandstone at Corbula Gulch in central Utah, USA. Shale statistics are computed from outcrop observations. Although slight anisotropy was observed in mean length and variogram ranges parallel and perpendicular to pale of low , the anisotropy is not statistically significant and the estimated mean length is 5.4 m. Truncated Gaussian simulation was used to create maps of shales that are placed on variably dipping stratigraphic surfaces interpreted from high-resolution 3D GPR surveys, outcrop interpretations, and boreholes. Sandstone permeability is estimated from radar responses calibrated to permeability measurements from core samples. Experimentally designed flow simulations examine the effects of variogram range, shale coverage fraction, and trends in shale coverage on predicted upscaled permeability, breakthrough time, and sweep efficiency. Approximately 1500 flow simulations examine three different geologic models, flow in the 3 coordinate directions, 16 geostatistical parameter combinations, and 10 realizations for each model. ANOVA and response models computed from the flow simulations demonstrate that shales decrease sweep, recovery, and permeability, especially in the vertical direction. The effect on horizontal flow is smaller. Flow predictions for ideal tracer displacements at Corbula Gulch are sensitive to shale-coverage fraction, but are relatively insensitive to twofold variations in variogram range or to vertical trends in shale coverage. Although the hydraulic effects of shale are statistically significant, the changes in flow responses rarely exceed 20%. As a result, it may be reasonable to use simple models when incorporating analogous shales into models of reservoirs or aquifers.     

基于Hough变换的建筑物半自动提取

提出了一种基于Hough变换的建筑物半自动提取方法.该方法针对由人工给定建筑物的初始角点并通过统计屋顶主方向对Hough变换的搜索范围和搜索角度进行限制,从而稳定快速地提取出屋顶的边缘.然后利用最小二乘的方法对提取出的屋顶边缘进行精确对中,实现了对平顶直角建筑物以及人字形建筑物的有效提取.     

论网格与网格地理信息系统

文中论述和分析了网格、空间信息网格和地图上的格网等概念。在分析目前WebGIS的主要关键技术及实际功能和效果的基础上,从软件和数据两个方面分析了目前WebGIS存在的问题及其原因。针对目前WebGIS对于网格技术的不适应性,提出了关于基于多智能代理的网格地理信息系统的思考,论述了代理、移动代理和智能代理及其优势,给出了系统的体系结构,并对系统客户端、服务器及其智能代理技术进行了说明,研究了系统中移动代理的设计、迁移机制、巡回路线规划和通信机制等。最后给出了初步的结论和讨论意见。     

Atmospheric Electrification in the Solar System

Atmospheric electrification is not a purely terrestrial phenomenon: all Solar System planetary atmospheres become slightly electrified by cosmic ray ionisation. There is evidence for lightning on Jupiter, Saturn, Uranus and Neptune, and it is possible on Mars, Venus and Titan. Controversy surrounds the role of atmospheric electricity in physical climate processes on Earth; here, a comparative approach is employed to review the role of electrification in the atmospheres of other planets and their moons. This paper reviews the theory, and, where available, measurements, of planetary atmospheric electricity which is taken to include ion production and ion–aerosol interactions. The conditions necessary for a planetary atmospheric electric circuit similar to Earth’s, and the likelihood of meeting these conditions in other planetary atmospheres, are briefly discussed. Atmospheric electrification could be important throughout the solar system, particularly at the outer planets which receive little solar radiation, increasing the relative significance of electrical forces. Nucleation onto atmospheric ions has been predicted to affect the evolution and lifetime of haze layers on Titan, Neptune and Triton. Atmospheric electrical processes on Titan, before the arrival of the Huygens probe, are summarised. For planets closer to Earth, heating from solar radiation dominates atmospheric circulations. However, Mars may have a global circuit analogous to the terrestrial model, but based on electrical discharges from dust storms. There is an increasing need for direct measurements of planetary atmospheric electrification, in particular on Mars, to assess the risk for future unmanned and manned missions. Theoretical understanding could be increased by cross-disciplinary work to modify and update models and parameterisations initially developed for a specific atmosphere, to make them more broadly applicable to other planetary atmospheres.     

浅议电法找水中的一个误区

在河北GY北部山前地带及河北TX西北部山区等环境条件下,采用电法找水,不应过分依赖于低阻岩带或灰岩溶隙选定井位,特别是电测深H型曲线,如低阻出现深度较浅,且未出现低阻平直段,曲线尾部又近于45°渐近线,则可能是浅层的亚粘土、砂质粘土形成的,不具备成井条件;而A型曲线如在深部(200～350m)出现高阻平直段,则可推测为基岩深部的脉状裂隙水反映。实践证明采用这种方法确定钻井点位是可行的,对于在我国北方寒武、奥陶系地层中寻找地下水资源,具有一定的参考价值。     

地震序列较强余震最小二乘拟合预测的方法研究

本研究给出了针对地震序列较强余震发生时间进行快速预测的一种方法,即最小二乘拟合预测方法.该方法包括:最小二乘拟合预测模型的建立、预测模型的各种可信性检验及模型预测等内容.震例研究表明,该方法在大(强)地震现场震情分析中可望发挥积极作用.     

综合物探解决黄土区煤田复杂地质问题

山西某矿位于构造堆积盆地，属黄土匠陵地貌，区内被第四系黄土覆盖，为解决该矿地质构造及水文地质问题，采用三维地震勘探与瞬变电磁法、直流电测深法相结合的勘探方案。利用三维地震勘探解决目的层赋存形态及其地质构造问题，再利用瞬变电磁法进行平面控制，以使平面及深度解释误差达到勘探要求；应用直流电测深法及瞬变电磁进行勘探，在正反演解释的基础上对其资料综合分析、对比，并结合三维地震资料，确定地质构造的富水及导水性。     

地面-坑道激电测深方法在山东玲珑断裂带深部找矿中的应用

在山东玲珑断裂带深部找矿中,考虑断裂带处在地电干扰和地形变化复杂地段,且深部地质体产状变化较大,仅依据半空间地面物探方法很难摸清地质体的展布形态,盲目布设钻孔会造成找矿成本的提高。为精确反演深部矿体的边界范围、走向及倾向,提高钻孔见矿率,降低找矿成本,在山东玲珑断裂带地面、坑道采用立体物探技术,试验通过布设多条方位不同的地-坑、坑-坑和地-地纵横激电中梯剖面和双向三极测深剖面,进行了二维电法剖面反演。在地面-坑道激电测深方法中,地面-坑道供电,坑道测量探测深度与坑道深度呈正相关,反映了深部巷道底板以下电阻率和极化率的分布状况,可以实现深地探测目的。由于地面-坑道供电,坑道测量装置处在半空间和全空间两个部分,需要采用"镜像法"和地下倾斜偶极源电流场特征对其装置系数k值重新推导,以反映坑道空间岩矿体真实电阻率的变化。坑道中梯剖面异常与单向三极剖面异常、双向三极电测深反演结果对应较好。经钻探验证,矿体分布与物探推断高极化体基本一致,为快速准确布设深部钻孔提供资料。     

电测深及水文测井在塔里木盆地寻找地下淡水体的研究

本文通过对多年来积累的水文物探资料的初步分析研究,发现含水层的电性特征与地下水矿化度之间存在着幂函数的变化规律,其相关关系式为Ｍｓ＝３３．９３５３ρｓ＾－１．１４１６和ＭＪ＝３３．５８９２ρｓ＾－１．０４９６,这在近年来寻找地下淡水体方面发挥了重要作用,并取得了良好的社会效益和经济效益。