人工神经网络在基桩低应变完整性检测中的应用   总被引：2，自引：0，他引：2  

冯劲  高广运 《岩土工程技术》2005,19(1):5-8

目前基桩低应变完整性检测数据的后期处理有很多方法 ,但分析中人为干预较多。利用人工神经网络强大的非线性映射能力和学习训练功能 ,提出了基于BP网络的基桩完整性检测模型。该模型基于现场实测资料 ,避免了数据处理过程中各种人为干预。应用该模型对工程实例进行了分析 ,训练和测试网络结果说明该方法能够快速、方便地对基桩质量进行模式识别  相似文献   

CM桩复合地基承载力试验结果分析     

石启斌 《岩土工程技术》2005,19(2):106-108,F003

通过对“CM桩复合地基”(以下简称CM地基 )承载力试验结果的分析 ,获得了一些有益的结论 ,对其在徐州地区的推广和应用提供参考。  相似文献   

Electrokinetic remediation of an electroplating site: design and scale-up for an in-situ application in the unsaturated zone   总被引：1，自引：0，他引：1  

S. Wieczorek  H. Weigand  M. Schmid  C. Marb   《Engineering Geology》2005,77(3-4):203-215

In-situ electrokinetic remediation of contaminated soils requires integrated approaches and adequately engineered setups to control relevant mass fluxes. Based on laboratory findings, this study presents the design of a pilot-scale remediation at an operating electroplating site. The fine-textured soil developed from Jurassic limestone exhibits a chromium, copper, nickel, and zinc contamination down to depths of more than 4 m. The feasibility of an electrokinetic remediation in the unsaturated zone was tested in a lab-scale experiment with subsoil material sampled at the site. The electrodes were placed in water-impermeable, ion-selective membrane wells. This construction allows the necessary watering of the electrodes, maintains unsaturated conditions in the soil compartment, and enables the transfer of contaminant ions into the wells. In addition, the soil is protected from pH changes caused by water electrolysis at the electrodes. The setup includes a watering and drainage system to compensate the electroosmotic water flux and impede desiccation of the anodic region. With a direct current of 70 V and an electric field strength of 2.2 V cm⁻¹, contaminant removal rates amounted up to 27% and 66% (w/w) of the initial zinc/copper and chromium/nickel concentrations. Copper, nickel, and zinc accumulated in the cathode well, while chromate species were enriched in the anode well. Given the successful lab-scale remediation, the pilot plant was designed for the in-situ treatment of a soil volume of 12 m³ below a production hall. A power of 500 V DC at a maximum current of 30 A is supplied by a transformer rectifier. This yields an electric field strength comparable to the lab-scale experiment and thereby similar contaminant transport velocities. A vacuum distillation unit is employed for process water reuse and to control electrolyte conductivity. To cope with chlorine gas generation at the anodes a gas absorber unit is employed. According to the lab-scale results, about 2, 9, 9, and 15 kg zinc, chromium, copper, and nickel, respectively, are expected to be removed from the field plot during an operation time of 10 months.  相似文献   

PHYSICAL STRUCTURE OF GEOGRAPHICAL ENVIRONMENT-INTEGRITY AND DISPARITY,GENERALITY AND INDIVIDUALITY   总被引：1，自引：0，他引：1  

李春芬 《中国地理科学(英文版)》1993,(4)

Integrity and disparity are two of the basic characteristics implied in the scientific connotation of the physical environment as a material system. From a dialectical materialistic point of view the physical character of geographical environment of the earth surface is the unity in diversity. It is on such grounds that the two basic characteristics were put forth by the author in his monograph "Physical Structure of South American Geographical Environment" as the underlying theme. This holds true for the hierarchy of physical regions. For instance, the physical environment of the earth surface in unity behaves as a huge whole, yet, in differentiation into continents, it displays disparity; each continent differs from others and becomes an integrity in its own right. The same is true of regions of lower levels. In the case of generality and individuality of regional types and their constituent distributive areas in different continents, the same relationship exists among them. Owing to similar origin ea  相似文献   

GIS应用数据库设计二阶分析模式   总被引：5，自引：0，他引：5  

赵秀怡  熊庆文  涂建光 《武汉大学学报(信息科学版)》2003,28(1):100-104

提出了数据库设计二阶分析模式，将二者分别应用于空间数据建模和数据库结构设计中，并以国土资源与房地产管理综合管理系统数据库设计中房地关联部分为例对二阶分析模式的应用进行了说明，对模式的可行性进行了论证。  相似文献   

超声波透射法在检测大直径灌注桩完整性中的应用   总被引：2，自引：0，他引：2  

肖春喜 《岩土力学》2003,(Z1)

介绍了超声波透射法检测大直径灌注桩桩身完整性的原理、方法和现场检测技术。通过现场检测实例,给出了基桩存在缺陷时声参量的几种特征。检测结果表明:超声波透射法能够相当准确的判别长桩的多处缺陷。  相似文献   

分布式WADGPS完备性监测技术研究     

秘金钟  李毓麟 《全球定位系统》2002,27(4):2-8

介绍了分布式WADGPS系统中监测站和用户站的监测方法，讨论了监测站和用户站的粗差探测与分离，最后应用分布式WADGPS99‘陆基长距离试验和南海海上试验进行了数据处理和分析。  相似文献   

基于星基导航完好性监测及其海上应用系统的探讨     

李科  李胜全  沈明 《全球定位系统》2008,33(5):65-68

由于卫星导航信号强度弱易被干扰,可以通过人为手段（如GPS的SA）播发欺骗信息,使海上船只的导航信号容易被干扰、蒙蔽和控制。通过对星基导航完好性监测方法的探讨,介绍了通过建立一个卫星导航系统信息源完好性监测数据库,并利用地球同步卫星,将监测结果实时地传输到监控中心,来建立一套可靠性高、实时性强的海上卫星导航信息源完好性监测系统,解决我国海上特殊用户星基导航可靠性保障的问题。  相似文献   

Spatial Relations between Classes as Integrity Constraints     

Francesco Tarquini  Eliseo Clementini 《Transactions in GIS》2008,12(Z1):45-57

The quality and integrity of spatial data is very important to support interoperability among different systems. To reach this aim integrity rules defined by the application play an important role (for example, constraints between object classes). In this article, we propose a methodology to define integrity constraints using user level spatial relations between classes of individuals. We will also provide mapping rules from user level relations to geometric level operators to allow the computation of relations. As a case study, we will define the constraints for the class of rivers and some of its specializations.  相似文献   

非对称天然沸石陶瓷膜的制备及其性能表征   总被引：1，自引：0，他引：1  

张学斌  胡晓翠  陈小丽  刘杏芹 《矿物学报》2007,27(1):6-10

利用天然沸石为主要原料,制备出具有过滤功能和重金属离子吸附功能的天然沸石非对称陶瓷膜。非对称膜中支撑体、中间层膜和顶层膜的平均孔径分别为6.6μm、0.6μm和0.1μm。非对称膜单位压力降(1 MPa)下的氮气通量和水通量分别为:24.69×103m3/(m2h)和1.87×103m3/(m2h);对重金属离子(铅离子)吸附交换能力为7.13 mg/g。  相似文献