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911.
鉴于医疗建筑在防灾救灾中的重要地位和作用,本科考小组对雅安地区医疗建筑在芦山地震中的震害进行了调查,调查包括不同烈度区、不同结构类型和建筑年代、不同级别的医疗卫生机构,对结构构件、非结构构件、医疗设备的震害特征,以及其他影响医疗秩序和使用功能的因素做了阐述和分析,并总结了汶川灾后新建及重建项目的抗震效果.调查表明,雅安地区医疗建筑在建筑结构的抗震安全性及救灾功能的实现方面仍存在很多问题,反映了我国医疗建筑的普遍问题.因此,对医疗建筑的抗震设防,需要作进一步系统的研究.  相似文献   
912.
A mesocosm experiment was conducted to quantify the relationships between the presence and body size of two burrowing heart urchins (Brissopsis lyrifera and Echinocardium cordatum) and rates of sediment nutrient flux. Furthermore, the impact of seawater acidification on these relationships was determined during this 40-day exposure experiment. Using carbon dioxide (CO2) gas, seawater was acidified to pHNBS 7.6, 7.2 or 6.8. Control treatments were maintained in natural seawater (pH ≈ 8.0). Under normocapnic conditions, burrowing urchins were seen to reduce the sediment uptake of nitrite or nitrate whilst enhancing the release of silicate and phosphate. In acidified (hypercapnic) treatments, the biological control of biogeochemical cycles by urchins was significantly affected, probably through the combined impacts of high CO2 on nitrifying bacteria, benthic algae and urchin behaviour. This study highlights the importance of considering biological interactions when predicting the consequences of seawater acidification on ecosystem function.  相似文献   
913.
Abstract

The design of an alluvial channel affected by seepage requires information about five basic parameters: particle size, water depth, energy slope, seepage velocity, and average velocity. The conventional approach to predicting the incipient motion in an alluvial channel cannot be applied in the case of a channel affected by seepage. Metamodelling techniques are nowadays widely used in engineering design to simulate a complex system. Here, a metamodel is described which employs the radial-basis function (RBF) network to predict the seepage velocity and energy slope based on experimental data under incipient motion conditions. It was found that the model fits experimental data very well and provides predictions for the design. With the help of the metamodel generated by the RBF network, design curves based on the RBF metamodel are presented for use in designing an alluvial channel when it is affected by seepage.

Citation Kumar, B., Sreenivasulu, G. & Ramakrishna Rao, A. (2010) Metamodel-based design of alluvial channels at incipient motion subjected to seepage. Hydrol. Sci. J. 55(3), 459–466.  相似文献   
914.
Enhanced coagulation treatment of bacteria‐containing raw water was studied by using three series of composite coagulants, that were prepared by combining polydiallyldimethylammonium chloride (PDADMAC) with different intrinsic viscosity values (0.55–2.47 dL/g) and mass percentages (5–20%) with polyaluminum chloride (PAC), aluminum sulfate (AS), and the composite of aluminum sulfate and ferric chloride (A‐F), respectively. The coagulants were tested by jar tests for the efficiencies to remove bacteria in raw water and to kill bacteria in settled sludge. It was found that when the residual turbidity of supernatant after sedimentation reached the control standard of 2 NTU in drinking water plant, the bacteria‐removing rates of PAC, AS, and A‐F were 92.22, 92.60, and 94.99%, respectively, and the bactericidal rates were 2.52, 1.22, and 2.94%, respectively. Contrastively, the bacteria‐removing rates of PAC/PDADMAC, AS/PDADMAC, and A‐F/PDADMAC could reach 95.45, 96.90, and 98.89%, respectively, and the bactericidal rates could reach 86.60, 91.81, and 96.98%, respectively. It could be deduced from the results that the bactericidal efficiencies of composite coagulants stemmed from the bactericidal action of PDADMAC, and the inorganic coagulants had little bactericidal function.  相似文献   
915.
何书镜 《地理空间信息》2013,11(2):122-124,129
探讨了GNSS接收机天线多路径效应的计算和分析方法,分别运用由多路径计算原理编制的数据分析软件和TEQC软件处理整体式GNSS接收机获取的数据,并进行对比分析,其结果说明多路径效应的大小与高度角存在线性关系。在实际数据预处理中,可通过分析软件代替TEQC,简单方便地获得站点的多路径信息,对站点的数据评定提供有效的质量信息。  相似文献   
916.
王卫民 《地理空间信息》2013,11(1):150-152,16
要实现测绘强国,一要有先进发达的测绘科技,二要有规范繁荣的测绘市场,而二者平衡发展的关键就在于人才。测绘师在测绘行业中起着至关重要的作用。测绘师的能力通常可以反映测绘事业的整体水平。作为一个合格的注册测绘师必须具有测绘职业道德、素质修养和专业技能,才能胜任功能社会的需要。注册测绘师的成长需要经历学校培养、见习锻炼和执业发展3个阶段,从而逐步形成测绘师自身和测绘行业的社会地位和专业魅力。  相似文献   
917.
为了满足多卫星系统完好性监测的需要,本文通过对比不同卫星系统定位结果的方法来监测各个卫星系统的可用性。利用上述方法对实测的三模(GPS、GLONASS和COMPASS)数据进行了处理,结果表明该方法具有可行性,可为多模GNSS接收机的自主完好性监测提供参考信息。  相似文献   
918.
当前国家以及各地区主体功能区区域规划已经完成,如何对规划后的主体功能区进行监测,是当今主体功能区监测面临的重大课题。资源三号卫星数据为主体功能区监测提供新的数据源。本文以资源三号卫星数据为数据源,开展主体功能区监测应用,并建立主体功能区监测平台,用于主体功能区监测与地物提取。  相似文献   
919.
沈旭章 《地球物理学报》2013,56(6):1895-1903
地壳和岩石圈变形特征研究对于深入了解中强地震的深部孕震环境具有重要科学意义.本文联合P和S波远震接收函数偏移成像结果,对发生过芦山7.0地震和汶川8.0地震的龙门山断裂带及附近区域地壳和岩石圈结构进行分析.结果揭示出在青藏高原向四川盆地过渡的龙门山断裂带,Moho面和岩石圈底界面(LAB)呈现出强烈变形,特别是芦山地震和汶川地震震源区下方地壳出现了错断、下凹,岩石圈也呈现下凹变形特征.这种地壳及岩石圈变形所代表的高应力的积累可能是汶川和芦山地震发生的重要深部地球动力学背景.  相似文献   
920.
Many sensors have their bands overlapped and therefore do not set a normal space. If a spectral distance is measured, as in first-order statistical classifiers, the direct consequence is that the result will not be the most accurate. Image classification processes are independent of the spectral response function of the sensor, so this overlap is usually ignored during image processing. This paper presents a methodology that introduces the spectral response function of sensors into the classification process to increase its accuracy. This process takes place in two steps: first, incident energy values of the sensors are reconstructed; second, the energy of the bands is set in an orthonormal space using a matrix singular value decomposition. Sensors with and without overlapping spectral bands were simulated to evaluate the reconstruction of energy values. The whole process was implemented on three types of images with medium, high and very high spatial resolution obtained with the sensors ASTER, IKONOS and DMC camera, respectively. These images were classified by ISODATA and minimum distance algorithms. The ISODATA classifier showed well-defined features in the processed images, while the results were less clear in the original images. At the same time, the minimum distance classifier showed that overall accuracy of the processed images increased as the maximum tolerance distance decreased compared to the original images.  相似文献   
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