曹妃甸深水港址开发研究

论述曹妃甸港址开发的比较优势和建设前景,分析该港址具有天然的深水优势和突出的地理区位优势,蕴育着巨大的开发潜力。港口建设和临港产业带开发,将对环渤海以及北方地区经济发展产生极大的带动作用。     

港珠澳大桥主体工程初勘工作介绍

港珠澳大桥包含海中主体工程及两岸接线工程。主体工程初勘结合桥型、隧道和人工岛等不同结构形式,针对工程区基岩埋深变化大,地质地层复杂,构筑物多样等特点,提出专门勘察技术要求。结合设计和地层特征,钻孔终孔采取双控原则。根据人工岛筑岛工程需要,开展了两组海上抽水试验。勘察结果表明:虽然港珠澳大桥桥址区存在软土、风化岩、震陷及砂土液化等不良地质条件,但其影响程度有限,中-微风化花岗岩岩体坚硬结构完整,为良好的基础持力层。勘察成果为该阶段设计方案提供了地质支持。     

青皇岛市青龙县城工程场地地震危险性分析

本文以秦皇岛市青龙县城工程场地为例，采用Ａ·Ｄｅｒ·Ｋｉｕｒｅｇｈｉａｎ和Ａ·Ｈ－ＳＡｎｇ断层－破裂模型，通过潜在震源识别及震源区划分、地震动参数确定、地震动衰减公式计算模型建立及不确定性校正、场地地震危险性评定等思路和方法，对该场地进行了地震危险性分析和评定。结果认为，该场地建筑物按５０年使用期，地震烈度为６．７２度，其地面峰值加速度为０．１０３ｇ；一般建筑物按Ⅵ度烈度设防，重要建筑则按Ⅶ度烈度设防；可能产生的Ⅷ度烈度主要来自西南方向的唐山地震区。     

地脉动在泉州市区地基土层场地评价中的应用

根据实际观测资料研究了泉州市区的地脉动特征以及脉动频谱特性与场地有关参数之间的关系。结果表明,地面脉动卓越周期的变化与场地土层构造有关,与场地工程地质条件的变化相对应。测试结果反映了地基土刚度(剪切波速)的变化与场地覆盖层厚度的大小有关。认为覆盖层厚度是影响地脉动卓越周期的重要原因。     

Prioritizing conservation potential of arid-land montane natural springs and associated riparian areas

Using inventory data and input from natural resource professionals, we developed a classification system that categorizes conservation potential for montane natural springs. This system contains 18 classes based on the presence of a riparian patch, wetland species, surface water, and evidence of human activity. We measured physical and biological components of 276 montane springs in the Oscura Mountains above 1450 m and the San Andres Mountains above 1300 m in southern New Mexico. Two of the 18 classes were not represented during the inventory, indicating the system applies to conditions beyond the montane springs in our study area. The class type observed most often (73 springs) had a riparian patch, perennial surface water, and human evidence. We assessed our system in relation to 13 other wetland and riparian classification systems regarding approach, area of applicability, intended users, validation, ease of use, and examination of system response. Our classification can be used to rapidly assess priority of conservation potential for isolated riparian sites, especially springs, in arid landscapes. We recommend (1) including this classification in conservation planning, (2) removing deleterious structures from high-priority sites, and (3) assessing efficiency and use of this classification scheme elsewhere.     

县市级义务教育学校区位配置优化设计与实验

 合理规划学校布局是实现义务教育均衡发展和落实就近入学政策的一个重要途径。为满足县市级中小学校空间布局规划需求,本文以区位配置优化方法解决学校区位选址问题。以平均入学距离为目标,以学校总数、学校学额为约束条件,分别构建P中值指派规划和整型规划数学模型。根据学校与居民地之间的空间分布特征进行模型简化,使模型计算效率大幅度提升。因指派规划模型约束矩阵每列非零元素不超过2个,分枝切割算法能获得近似最优解(与最优目标之差小于0.01%);整型规划模型约束矩阵近似于完全单位模矩阵,分枝切割算法通常能获得最优解。在ArcGIS 10 Geoprocessing框架中,整合ArcGIS网络分析、Coin-or Python线性规划建模工具PuLP 1.4.7和线性规划软件Cplex 12,实现模型建模、模型解算和优化结果可视化。在配置Intel 酷睿2双核2.44GHz CPU和2GB内存的计算机环境中,对于有1276个居民点和50所学校的县域进行网络分析、模型建模、模型结算和结果输出。优化结果表明:学校布局调整后学生平均入学距离明显降低,本文构建的优化模型在县市级较大规模的学校选址规划中具有实用价值。     

High-altitude wind velocity at Oukaimeden observatory

This paper aims at studying the wind at 200 mbar over the Moroccan observatory Oukaimeden, as high-altitude winds have been adopted as a useful parameter for site characterization in terms of the suitability of a site for the development of some adaptive optics techniques. The data used come from the National Center for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis data base, which is widely acknowledged as being reliable. Statistical analyses of 200-mbar wind speed since 1983 are performed. Comparison with some of the main observatory sites worldwide qualifies Oukaimeden as one of the best observatory sites in terms of 200-mbar wind statistics. Our analysis of a record of seeing measurements during the years 2003 and 2004 concludes that while 200-mbar wind speed can be used as a parameter for ranking astronomical sites in term of their suitability for adaptive optics, it cannot be used for the whole atmospheric seeing prediction. A comparison of monthly values of the seeing parameter at Oukaimeden, La Silla and Paranal demonstrates the high seeing quality of Oukaimeden, as the seeing values measured were lower than those of La Silla and Paranal for most of the time during the comparison period. Furthermore, a statistical analysis of atmospheric stratified seeing, wavefront coherence time and isoplanatic angle measured with a Multi-Aperture Scintillation Sensor instrument over Paranal from 2004 to 2007 have been performed. We found good correlations between 200-mbar wind velocity and levels 4, 5 and 6 seeing, wavefront coherence time and isoplanatic angle, with corresponding correlation coefficients of 0.74, 0.79, 0.70, 0.97 and 0.78.     

基于数值模拟的射电望远镜台址测风塔位置优选方法研究

射电望远镜天线结构设计和观测任务的正常进行都需要台址风场信息.随着望远镜性能要求的提高,天线结构设计越来越复杂,风载荷对天线观测时造成的指向影响也越发明显,如何在设计时保证结构刚度和强度,在观测时提高有效观测时间,都需要准确的风场数据.由于传统台址测风塔布置方法无法对测风塔拟设点的可靠性做出定量化评估,因此提出一种基于数值模拟优化测风塔位置的方法.数值模拟基于规范参数设置边界条件,与实测数据比较,整体趋势吻合,满足精度需求.对试验台址设置了4个测风塔位置,经分析P2点与天线位置的风速均方根误差值(root-mean-square error, RMSE)最小,测得的数据更能表征天线区域的风场特性.