关于智能体环境下空间数据集成方法研究          下载免费PDF全文

杨仕勇 《山东国土资源》2011,27(9):48-52

在分析总结空间数据集成研究的发展历程及其存在的问题基础上,充分考虑空间数据海量、数据源异构性的特点,引入智能体概念和结构,提出了基于多智能体系统的空间数据集成模式,并对该模式的体系结构与功能实现进行了设计。  相似文献   

加强实验室管理以促进实验室建设的思考     

谢麟 《福建地理》2011,(4):85-89

以湿润亚热带山地生态国家重点实验室培育基地为例,介绍了实验室平台、人才队伍、及管理现状．从团队创新、实验室文化、知识管理等方面入手,探讨了加强实验室管理促进实验室建设的思路和方法．  相似文献   

中亚热带植物排放甲烷研究初报   总被引：1，自引：0，他引：1  

易黎明  谢锦升  杨燕华  高玉春  杨玉盛 《福建地理》2011,(1):26-31

甲烷(CH4)是大气中第二大温室气体,近年有研究发现在有氧条件下陆生植物也能排放CH4.本研究对中亚热带51种树木离体叶片在有氧环境下进行室内培养,发现21种植物能排放CH4,CH4排放速率范围为0.11～1.37 ngCH4.g-1 DW.h-1,平均排放速率为0.59ngCH4.g-1DW.h-1.植物是否排放CH4及其排放速率与观测条件密切相关.观测的51种植物中包括40种乔木树种和11种灌木树种,分别有15种和6种植物可排放CH4,CH4平均排放速率分别为0.69 CH4.g-1DW.h-1和0.30 ngCH4.g-1DW.h-1,且乔木和灌木之间存在极显著差异(P<0.05).  相似文献   

应用于非开挖中减小扭矩的二糖有机物的室内研究          下载免费PDF全文

童红梅  明磊 《探矿工程》2011,38(4):61-63

非开挖工程常会遇到的淤泥质高粘土土层,施工中往往需要较大的剪切力才可以破坏土体,因此常常会导致钻杆扭矩过大,导向和扩孔难以进行,造成施工困难,延误工期等后果。针对此类地层,通过室内试验研究和对分子结构的作用机理的分析,介绍了一种应用到钻井液中能有效地解决该类地层中的高扭矩问题的常见二糖有机物,并在实际工程中得到有效应用。  相似文献   

Geometric characteristics and evolution of a tidal channel network in experimental setting   总被引：3，自引：0，他引：3  

Brigitte M. Vlaswinkel  Alessandro Cantelli 《地球表面变化过程与地形》2011,36(6):739-752

This paper reports on a laboratory study that aims to reproduce a tidal channel network, in order to enhance the understanding of the morphodynamic evolution of the channel characteristics as the network expands and finally reaches equilibrium. A high‐resolution laser system scanned the bed topography at different time steps creating multiple digital elevation models of the channel network. Two hundred and seventy individual channel segments are analyzed and cross‐correlated in terms of their width, depth and length. The laboratory results show positive linear correlations between depth and width as well as between length and width of channel segments of the network configuration at final equilibrium. In a downstream direction, channels appear to widen more than they deepen, indirectly a sign that discharge has a stronger control on channel width than on depth. In contrast to fluvial drainage networks that commonly display fractal and scale‐invariant behavior, the geometric properties of the experimental tidal creek network shows scale dependence. Channel attributes exhibit consistent patterns of exponentially decreasing abundance, with increasing creek length, depth and width. The nature of the observed exponential distributions within creek attributes (width, depth, length) allows for statistical predictability of relative creek attribute dimensions downstream and through time. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

Impact of subsurface rock fragments on runoff and interrill soil loss from cultivated soils   总被引：1，自引：0，他引：1  

T. Smets  M. López‐Vicente  J. Poesen 《地球表面变化过程与地形》2011,36(14):1929-1937

Field and laboratory studies have indicated that rock fragments in the topsoil may have a large impact on soil properties, soil quality, hydraulic, hydrological and erosion processes. In most studies, the rock fragments investigated still remain visible at the soil surface and only properties of these visible rock fragments are used for predicting runoff and soil loss. However, there are indications that rock fragments completely incorporated in the topsoil could also significantly influence the percolation and water distribution in stony soils and therefore, also infiltration, runoff and soil loss rates. Therefore, in this study interrill laboratory experiments with simulated rainfall for 60 min were conducted to assess the influence of subsurface rock fragments incorporated in a disturbed silt loam soil at different depths below the soil surface (i.e. 0.001, 0.01, 0.05 and 0.10 m), on infiltration, surface runoff and interrill erosion processes for small and large rock fragment sizes (i.e. mean diameter 0.04 and 0.20 m, respectively). Although only small differences in infiltration rate and runoff volume are observed between the soil without rock fragments (control) and the one with subsurface rock fragments, considerable differences in total interrill soil loss are observed between the control treatment and both contrasting rock fragments sizes. This is explained by a rapid increase in soil moisture in the areas above the rock fragments and therefore a decrease in topsoil cohesion compared with the control soil profile. The observed differences in runoff volume and interrill soil loss between the control plots and those with subsurface rock fragments is largest after a cumulative rainfall (P_cum) of 11 mm and progressively decreases with increasing P_cum. The results highlight the impacts and complexity of subsurface rock fragments on the production of runoff volume and soil loss and requires their inclusion in process‐based runoff and erosion models. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

室内定轨移动摄影测量控制系统设计与实现     

李国玉  石波  吴玮  李峰  高乐 《测绘科学》2011,36(3):197-198,206

在室内定轨移动摄影测量系统中,自动化、智能化的控制系统是其稳定可靠工作的重要保障.该摄影测量系统需要对轨道上的移动平台和摄影测量机构进行远程操作,为了实现稳定、可靠的控制,设计研发以单片机为控制核心的遥控系统;摄影测量机构是由五台非量测数码相机拼接而成,为了实现五台相机同步摄影,设计完成相机同步曝光装置.实验表明该系统...  相似文献   

移动曲面拟合用于高程控制测量的探讨     

孟冰 《现代测绘》2011,34(4):38-39

多项式曲线拟合、三次样条曲线拟合、多项式曲面拟合、多面函数曲面拟合、移动法曲面拟合是全球定位测量水准拟合常用方法,本文结合实例,分析多种方法获得数据的精度,并通过工程实例比较和分析,认为移动法曲面拟合拟合法精度更高且稳定,具有较高的可靠性和实用价值。  相似文献   

基于互联网的移动GIS及其在测量标志信息管理中的应用   总被引：1，自引：0，他引：1  

徐琳 《现代测绘》2011,34(4):46-48

移动GIS是地球信息科学发展的一个热点方向,它综合了地理信息系统、遥感、全球定位系统、互联网、移动数据通信等多种技术,具有广阔的应用前景。本文在阐述基于互联网的移动GIS的特点、架构、接入方式、工作原理等技术路线的基础上,详细论述了采用移动GIS技术后建立的测量标志管理信息系统能够实现的主要功能、优缺点等,探讨使用移动GIS管理测量标志普查信息的可行性。  相似文献   

DLT方法在遥感相机几何定标中的应用     

郑逢杰  余涛  陈兴峰  谢东海  袁国体  兰进京 《测绘与空间地理信息》2011,34(2):26-29

为建立适用于遥感相机定标的实验室,需要有几何标定的算法和软件对摄影图像进行计算.使用近景摄影测量中基于3维控制场的定标方法,对单CCD四波段遥感相机进行了几何定标,研究并自主编程实现了直接线性变换DLT(Direct Linear Transformation)算法,与基于空间后方交会算法的定标结果进行了精度对比.结论...  相似文献