侧扫声纳在水下坡脚线位置探测中的精度分析

根据国家海洋局印发的《海籍调查规范》,填海工程用海范围算至填海边坡水下坡脚线。在填海工程竣工验收中,水下坡脚线主要使用侧扫声纳获取。通过对侧扫声纳探测水下坡脚线位置的误差来源进行分析,提出了一系列提高侧扫声纳水下坡脚线位置探测精度的措施,并将其应用到实际工作中,对侧扫声纳水下坡脚线位置探测精度进行了验证。结果表明,侧扫声纳在填海工程水下坡脚线探测中的位置精度满足《海籍调查规范》中水下坡脚线平面位置精度要求。     

不确定度在多波束测深数据质量评估中的应用

在海道测量中,由于无法对测量数据进行多余和重复观测,因而不能精确测定各种误差,同时也几乎没有测量成果质量的控制指标,这正是多波束测深数据质量评估所面临的现实且急需解决的难题。基于国际海道测量规范S-44(5th)的要求,研究了不确定度在多波束数测深数据质量评估中的应用。通过实例分析可知,测量结果的可用性在很大程度上取决于其不确定度的大小,不确定度越小,说明测量结果质量越高,越具有可靠性。因此,将不确定度充分合理地应用于多波束测深数据处理和评估是一种最为理想的途径。     

基于CryoSat-2雷达高度计数据的南极内陆冰盖高程变化与物质平衡

南极冰盖对海平面影响巨大,高程变化测量是南极物质平衡监测的重要手段。采用欧空局CryoSat-2雷达高度计数据,通过提取卫星升降轨的地面交叉点,监测了南极内陆冰盖的高程变化（物质平衡）。结果表明,后向散射能量对Ku波段的CryoSat-2雷达高度计的高程数据具有一定的影响,经后向散射能量校正后,时间序列上的高程变化变得平缓,高程变化与已有的降雪数据相比,更加符合实际情况。2010年11月至2017年11月南极内陆冰盖高程变化趋势为（-1.1±0.2）cm·a^-1。西南极的Kamb冰流高程变化率为（38.7±1.1）cm·a^-1,Moeller冰流高程变化率为（-10.3±1.2）cm·a^-1,部分Thwaites冰川区域高程变化率为（-13.4±1.8）cm·a^-1,东南极的Wilkes Land出现高下降区,最高达-20 cm·a^-1。Dronning Maud Land虽然出现变化异常的点,但整体并没有显著的高程变化。南极内陆冰盖质量变化为（-10.6±6.2）Gt·a^-1,整体上南极内陆冰盖质量变化平缓,部分区域变化较大,Kamb冰流达到（17.9±0.5）Gt·a^-1,Moeller冰流达到（-3.4±0.4）Gt·a^-1,部分Thwaites冰川区达到（-3.7±0.5）Gt·a^-1。     

Contributory Factors and Distribution Characteristics of Asymmetric Deformation in Deep Tunnel

Aiming at the asymmetric deformation of the surrounding rock in deep tunnels, from the perspective of the mechanical environment of the rock layer, the physical characteristics of the surrounding rock and the geometric characteristics of the tunnel, five kinds of influencing factors for the asymmetric deformation of the tunnel surrounding rock were selected, and the change levels of various factors were established. Through orthogonal test methods, 25 sets of orthogonal test simulation schemes were designed to study the asymmetric deformation law of the surrounding rock of deep roadway under the combined action of various factors. Three surface displacements of the surrounding rock are used as indicators to weigh the influence of various factors on the asymmetric deformation of the surrounding rock. Through the Extreme Difference analysis and F Statistics comparison of the indicators, the dominant influencing factors affect the deformation of the surrounding rock are obtained. By studying the distribution of the maximum deformation position of the surrounding rock, we have obtained the asymmetry characteristics of the surrounding rock deformation. In addition, the simplified mechanical analysis of the key influencing factors of the deformation of the surrounding rock is given, and the distribution law of the asymmetric characteristics of the surrounding rock deformation is summarized. The above research can provide a certain theoretical reference for the asymmetric deformation control and supporting scheme design of the surrounding rock in deep roadway.

     

基于升降轨Sentinel-1A SBAS InSAR的西南山区滑坡隐患早期识别研究

以贵州省水城县为研究区,使用SBAS InSAR分别对2018-07~2019-07鸡场镇滑坡发生前31期升轨和30期降轨Sentinel-1A数据进行处理,提取地表形变场。结果表明：1）鸡场镇滑坡发生前SBAS InSAR形变场并未出现明显形变,已超出12 d重访周期SAR的形变监测能力;2）研究区存在5个明显形变区,推断与斜坡失稳、地下/露天采矿和矿物加工的抽排水有关;3）升降轨数据的SBAS InSAR形变场相互补充、验证,可显著提升卫星雷达对山区滑坡隐患早期识别和形变监测能力。研究方法可为贵州省以及中国西南山区滑坡隐患调查与早期识别提供技术参考。     

Planning hierarchical hospital service areas for maternal care using a network optimization approach: A case study in Hubei,China

Improving maternal health is one of the Sustainable Development Goals. Hospital service areas (HSAs), which contain most hospitalization behaviors at the local scale, are crucial for health care planning. However, little attention has been given to HSAs for maternal care and the hierarchy structure. Considering Hubei, central China, as a case study, this study aims to fill these gaps by developing a method for delineating hierarchical HSAs for maternal care using a network optimization approach. The approach is driven by actual patient flow data and has an explicit objective to maximize the modularity. It also establishes the hierarchical structure of maternal care HSAs, which is fundamental for the planning of hierarchical maternal care and referral systems. In our case study, 45 secondary HSAs and 22 tertiary HSAs are delineated to achieve maximal modularity. The HSAs perform well in terms of indices such as the Localization Index and Market Share Index. Furthermore, there is a complementary relationship between secondary and tertiary hospitals, which suggests the need for referral system planning. This study can provide evidence for the validity of the HSA and the planning of maternal care HSAs in China. It also provides transferable methods for planning hierarchical HSAs in other developing countries.     

基于三角网构建海底DEM的抽稀算法

为压缩海量水深数据,实现在高分辨率下快速、完整和准确地表示海底地形,提出了一种基于三角网拓扑结构的数据抽稀方法。该方法利用Delaunay三角网的模型优势,快速寻找与水深点相关的区域。根据水深点对区域贡献度大小决定取舍。实验表明,该方法充分顾及海底地形变化趋势,能有效识别海底地形特征点,并且抽稀速度快、失真小、精度高。     

基性-超基性侵入岩中-大比例尺专题地质填图实践——以塔里木板块东北部坡北岩体为例

目前,1∶5万地质填图规范中缺少对基性-超基性侵入岩填图方法的系统总结。以塔里木东北部坡北基性-超基性岩体为例,开展专题地质填图实践,在岩体地质、地球物理、遥感和地球化学综合调查的基础上,建立了科学问题、地质填图、矿床预测相结合的填图方法。将坡北基性-超基性岩体作为一个岩浆序列,根据岩浆性质与含矿性特征划分为2个岩浆亚序列,5个岩浆单元,分别对应不同的岩性组合。与岩浆亚序列相对应存在2类岩浆矿床,其中赋存铜镍矿化的岩相主要为橄榄岩相,含磁铁矿、钛铁矿的岩相主要与辉长岩、辉长苏长岩、辉石岩相有关。从野外踏勘、实测剖面等多个角度探讨了基性-超基性侵入岩1∶5万专题地质填图的方法,为此类工作提供了有益探索。     

南秦岭石泉北部将军河地区中酸性岩脉锆石U-Pb 年代学及其构造意义

南秦岭石泉北部中酸性岩脉发育,大部分岩脉与地层之间为构造接触关系,其形成时代及与区域金矿化的关系一直存在疑问。本研究采集石泉北部将军河地区中酸性岩脉13件,通过详细野外观察与室内鉴定,确定岩脉的岩性主要为闪长岩类。主量元素分析数据表明闪长岩的SiO_2含量为53.19%~68.48%,铝饱和指数A/CNK值为0.67~1.28,里特曼指数σ值介于1.4~2.93之间;微量元素分析数据表明中酸性闪长岩脉的稀土总量较低(ΣREE=44.54×10~(-6)~253.23×10~(-6)),REE球粒陨石标准化图呈轻、重稀土高度分馏的右倾型(HREE/LREE=6.15~14.87,(La/Yb)_N=5.97~38.67),具有弱负Eu异常(δEu=0.68~0.88);微量元素蛛网图显示富集大离子亲石元素(Ba、K、Sr)与高场强元素(Zr、Hf),相对亏损高场强元素(HREE、Ti、P、Th),岩脉可能来自于与消减作用有关的下地壳物质重熔。闪长岩脉的单颗粒锆石U-Pb年龄为771.9±3.4Ma,与汉南杂岩、安康北部的凤凰山内新元古代的岩浆活动具有同步性,指示区域伸展裂解的构造背景。根据野外填图推测南秦岭石泉北部将军河地区新元古代的岩脉对金矿的形成没有直接关系。