山东半岛漂浮铜藻和底栖铜藻气囊及生殖托的形态学比较分析

铜藻(Sargassum horneri)是主要分布于北太平洋西部的暖温带性海藻,是我国海藻场的重要组成物种之一,对于海洋环境、渔业资源具有重要支撑作用。除底栖生活外,铜藻可营漂浮生活。气囊和生殖托是铜藻适应漂浮生活的重要结构,但是二者与漂浮生活相适应的结构特点尚研究有限。本文对漂浮铜藻和底栖铜藻气囊、生殖托的数量以及主要形态学特征进行了统计学分析,结果显示:漂浮铜藻气囊体积显著小于底栖铜藻(P0.01),漂浮铜藻生殖托个数远少于底栖铜藻(P0.01),推测铜藻为了适应漂浮生境,其漂浮能力和有性生殖能力已经发生改变。     

Galileo广播星历评估及其对定位精度的影响

分析现阶段伽利略空间信号的精度,并评估伽利略广播星历及其对单点定位的影响。统计30 d健康卫星广播星历,结果表明,FOC和IOV两种类型的广播星历卫星轨道误差优于0.8 m,并且径向误差最小,法向误差次之,切向误差最大;伽利略卫星的钟差误差精度达到1.0 ns;从空间信号测距误差对伽利略卫星进行整体分析,广播星历精度优于1.0 m,FOC与IOV卫星精度相当;用广播星历进行事后单点定位的精度可以达到dm级。     

Probabilistic Approach of Coastal Defense Against Typhoon Attacks for Nuclear Power Plant

With the global wanning and sea level rising, it is widely recognized that there is an increasing tendency of typhoon occurrence frequency and intensity. The defenses code against typhoon attacks for nuclear power plant should be calibrated because of the increasing threat of typhoon disaster and severe consequences. This paper discusses the probabilistic approach of definitions about "probable maximum typhoon" and "probable maximum storm surge" in nuclear safety regulations of China and has made some design code calibrations by use of a newly proposed Double Layer Nested Multi-objective Probability Model (DLNMPM).     

龙须菜微卫星DNA的初步研究

为从龙须菜中分离含微卫星DNA的片段采用了2种方法,总共筛选了1 100个克隆。其中应用地高辛标记探针,通过菌落原位杂交方法,筛选得到13个克隆,测序结果显示仅有1个克隆含有微卫星DNA;PCR方法筛选出28个克隆,测序显示有23个克隆含有微卫星DNA。在总共测序的24个克隆中共有77个微卫星序列,每个克隆中含有的微卫星DNA在1～7个不等。核心序列重复次数在10次(含10次)以上的微卫星有38个,重复次数在10～38不等,重复次数在7～9次之间的微卫星有39个。在获得的微卫星序列中GA重复占97%,CA重复仅占3%。完全型微卫星55个,占71.4%;不完全型微卫星21个,占27.3%;复合型微卫星1个,仅占1.3%。龙须菜微卫星DNA的含量较低。     

单向流作用下沉底物体对水流结构和地形变化的影响

A one-phase model is established by using CFD(Computational Fluid Dynamics) software,which includes a hydrodynamic sub-model,an erosion-deposition and a moving boundary method.in the model,the velocity field surrounding obstacles on the seabed is computed by a three dimensional k-εturbulence closure sub-model.Erosion and deposition caused by the transportation of suspended load and bed load are also calculated.The evolution of bedform is simulated in a mobile grid technipue.The three-dimensional flow pattems and evolution of bedform around three different obstacles are simulated using the one-phase model.The hydrodynamic process and sediment transportation process surrounding the obstacles are reproduced in detail. The simuated results of bedform evolution are in good agreement with laboratory measurement results in 2005.     

基于随机森林的光子计数激光雷达点云滤波

新一代星载激光雷达卫星ICESat-2首次采用了微脉冲光子计数激光雷达技术,由于单光子探测的灵敏性导致数据在大气和地表下层产生了大量噪声,因此对光子计数激光雷达点云数据实现信号和噪声的分离是开展进一步应用研究的前提和基础。本文选择美国俄勒冈州和弗吉尼亚州2个研究区,采用MATLAS数据,根据光子点云数据的特点构造了12个光子点云特征,对所构造的特征利用随机森林进行变量筛选,用机器学习方法对光子点云进行分类,并将建立好的模型推广到整个研究区。研究结果表明,本文构建的分类器分类总精度达到了96.79%,Kappa系数为0.94,平均生产者精度和用户精度分别为97.1%和96.8%。在相对弱噪声、平坦地形区域和强噪声、复杂地形区域都取得较好的分类结果。本文结果显示了基于少量样本通过机器学习的方法构建模型,可以推广到较大范围区域的光子点云分类应用中。     

台风作用下淤泥质海岸动力地貌响应

基于200509号麦莎台风(近似百年一遇)作用前后杭州湾北岸龙泉-南竹港实测的海岸地形和水文资料,利用分形技术、冲刷深度和闭合水深等相关概念分析淤泥质海岸的剖面变化、岸线进退以及地形冲淤,进而探讨海岸响应台风作用的动力地貌行为.结果表明:1)台风作用前后的海岸动力地貌过程表现为水下类似沙坝的堆积体削平、凹处填洼,水下平台发育锯齿或较小的坝--槽,海岸剖面的分维数降低,剖面坡度处于平缓;2)麦莎台风对海床的整体冲淤幅度不大,这可能是由于研究区大潮讯的增水致使波浪对海床的塑造能力减弱以及码头的遮蔽作用造成;3)台风作用对海岸的冲刷深度约为0.8 m,闭合水深为9.5 m,近岸-1 m邻近区成为海岸响应台风作用最敏感的地带;泥沙主要在0 m到闭合水深区间的海床发生纵、横向运移.     

Characteristics and evolution of lacustrine turbidite of Chang-7 Member of Yanchang Formation in northern Shaanxi

Lacustrine turbidite of Chang-7 Member in the studied area consists of sihstone and fine sandstone with respect to grain size, which is feldspathic lithie sandstone, syrosem arkose and arkose with respect to mineral constitution affected by provenance. There are such apparent signatures as lithology, sedimentary structure, sedimentary sequence and well logs, to recognize turbidite. During the paleogeographic evolution of Chang-7 Member, lake basin and deep lake are both at their maximum extent during Chang-73 stage, resulting in the deposition of Zhangjiatan shale with widespread extent and of turbidite with fragmental-like. Deep lake line is gradually moving toward lake center and turbidite sand bodies are gradually turning better with better lateral continuity, connectivity and more thickness, from stages of Chang-73, Chang-72 and Chang-7t, which can be favorable reservoir in deep-water.     

改进的DisTrad模型在地形起伏区地表温度空间分辨率提升的应用

DisTrad（Disaggregation procedure for radiometric surface temperature）模型是常用于遥感地表温度空间分辨率提升的主要模型之一。DisTrad模型常面向空间范围有限、地形相对平坦的研究区域,且常选用植被参数（如植被指数或植被覆盖度等）作为关键参数。然而在空间范围较大、地形起伏地区,地表温度的空间变异可能无法完全通过植被参数解释。本研究选取四川盆地及毗邻地区为研究区,通过模拟数据研究DisTrad模型在地形起伏区地表温度空间分辨率提升中的适用性。数字高程模型（Digital Elevation Model,DEM）、归一化差值植被指数（Normalized Difference Vegetation Index,NDVI）等参数,采用滑动窗口逐步回归,将空间分辨率为6km的地表温度提升至空间分辨率为1km。研究结果表明,改进的模型在平原及海拔较低的高原地区提升获得的地表温度空间分辨率具有较高精度,均方根误差（Root Mean Square Error,RMSE）为0.5K左右;在地形起伏较大的地区,RMSE为4K,验证了改进的模型提升的可行性。