Three-Dimensional Modeling of Storm Surge and Inundation Including the Effects of Coastal Vegetation

Two-dimensional (2D) and three-dimensional (3D) hydrodynamic models are used to simulate the hurricane-induced storm surge and coastal inundation in regions with vegetation. Typically, 2D storm surge models use an enhanced Manning coefficient while 3D storm surge models use a roughness height to represent the effects of coastal vegetation on flow. This paper presents a 3D storm surge model which accurately resolves the effects of vegetation on the flow and turbulence. First, a vegetation-resolving 1DV Turbulent Kinetic Energy model (TKEM) is introduced and validated with laboratory data. This model is both robust enough to accurately model flows in complex canopies, while compact and efficient enough for incorporation into a 3D storm surge-wave modeling system: Curvilinear Hydrodynamics in 3D-Surface WAves Nearshore (CH3D-SWAN). Using the 3D vegetation-resolving model, three numerical experiments are conducted. In the first experiment, comparisons are made between the 2D Manning coefficient approach and the 3D vegetation-resolving approach for simple wind-driven flow. In a second experiment, 2D and 3D representations of vegetation produce similar inundations from the same hurricane forcing, but differences in momentum are found. In a final experiment, varying inundation between seemingly analogous 2D and 3D representations of vegetation are demonstrated, pointing to a significant scientific need for data within wetlands during storm surge events. This study shows that the complex flow structures within vegetation canopies can be accurately simulated using a vegetation-resolving 3D storm surge model, which can be used to assess the feasibility for future wetland restoration projects.     

Modelling of hydraulic fracturing process by coupled discrete element and fluid dynamic methods

A three-dimensional model is presented and used to reproduce the laboratory hydraulic fracturing test performed on a thick-walled hollow cylinder limestone sample. This work aims to investigate the implications of the fluid flow on the behaviour of the micro-structure of the rock sample, including the material strength, its elastic constants and the initialisation and propagation of fractures. The replication of the laboratory test conditions has been performed based on the coupled Discrete Element Method (DEM) and Computational Fluid Dynamics scheme. The numerical results are in good agreement with the experimental data, both qualitatively and quantitatively. The developed model closely validates the overall behaviour of the laboratory sample, providing a realistic overview of the cracking propagation towards total collapse as well as complying with Lame’s theory for thick-walled cylinders. This research aims to provide some insight into designing an accurate DEM model of a fracturing rock that can be used to predict its geo-mechanical behaviour during Enhanced Oil Recovery applications.     

沂水县王家庄子矿区金矿床地质特征

沂水县王家庄子金矿处于沂水汤头断裂带中段东侧,矿体赋存于其次级EW向和近SN向断裂构造中,赋矿围岩为紫苏花岗闪长岩和二长花岗岩。矿床成因类型为中低温重熔岩浆热液型金矿。     

宣郎地区基底构造特征

本文以宣城-郎溪地区的盆地为重点研究区,综合分析区域性重力、磁法资料,通过地面重力测量技术、高精度地面磁测,大地电磁测深等综合地球物理剖面,建立了宣城-郎溪地区基底构造格架,并探讨了其构造演化史。研究结果显示,宣城-郎溪地区基底构造格架主要呈北东向展布,研究区西部被江南深大断裂带所分割,断裂带北侧为北东向的古生界隆起,断裂带南侧为呈北东向展布的深厚断陷盆地,江南断裂带被一系列北西向断裂所切割,研究区南部主要受周王断裂带控制。此外,本次研究还认为,江南断裂带的北侧与北西断裂带的交汇处是找矿远景区。     

面向Z-5无人直升机航测的测绘质量检查体系及实证

基于无人直升机开展应急测绘具有重要意义,但目前缺乏针对无人直升机航摄系统的测绘质量检查体系及量化指标。本文提出基于Z-5无人直升机及配套航摄系统的测绘质量检查体系,包含数字航空摄影成果检查、空三加密成果检查和数字正射影像成果检查,并明确重要指标的量化数据。通过实际飞行验证,结果表明,Z-5无人直升机航摄系统能够满足应急测绘精度要求,其中4项内容可以进一步提高量化指标阈值,满足更为精准的无人机测绘要求。     

激光测高卫星波形饱和识别与测高误差改正初步研究

激光测高仪回波波形饱和现象客观存在,为增加可用激光点数目、提高饱和波形测高精度,本文提出了一种波形饱和识别与测高误差改正方法,首先,利用回波波形峰度系数对饱和波形进行识别,然后,针对饱和现象对波形高斯拟合的影响,计算高斯拟合波形与原始波形相交区域的形心位置,以形心位置差异确定因波形饱和导致的测高误差并改正。最后,采用ICESat/GLAS（Ice,Cloud and land Elevation Satellite/Geo-science Laser Altimeter System）在青海湖、纳木错、色林错采集的波形数据进行实验。结果表明,经本文算法改正后数据误差均值为0.03 m,大型湖泊区域可实现约0.05 m的测高精度,结合峰度的饱和识别方法可以对波形进行有效筛选,可发现GLAS遗漏的饱和波形,饱和改正算法可以有效改正波形饱和引起的测高误差,改正后精度明显优于GLAS提供的饱和改正结果,相关结论对高分七号卫星激光波形处理有一定参考价值。     

缢蛏糖原磷酸化酶基因多态性与糖原含量的关联分析

为探究缢蛏糖原磷酸化酶基因(Sc-GPH)与糖原含量的关系,本研究克隆获得Sc-GPH cDNA全长,检测其在不同组织、不同月份的表达模式,并在Sc-GPH基因编码区筛选与糖原含量关联的SNP位点.结果表明,Sc-GPH cDNA全长为3963 bp,开放阅读框为2541 bp,编码846个氨基酸;氨基酸序列多重比对和系统发育树显示,缢蛏与欧洲大扇贝、虾夷扇贝、长牡蛎等贝类亲缘关系较近,而与哺乳类、甲壳类、昆虫类亲缘关系较远.实时荧光定量PCR结果显示,Sc-GPH在8个组织中均有表达,其中在外套膜和足中表达量最高(p<0.01),推测与其糖原存储能力有关;不同月份的缢蛏外套膜和足中,Sc-GPH在8月表达量最高,而此时糖原含量较低,说明Sc-GPH的表达可能受缢蛏生殖周期的影响.以缢蛏"甬乐1号"群体为实验材料,在Sc-GPH基因编码区筛选到4个与糖原含量相关SNP位点,其中c.930T>C位点在台州野生群体中得到进一步验证,该位点为高糖原缢蛏分子标记辅助选育提供了候选标记.     

1956—2018年青海省黄河流域降水变化特征分析及预测

本研究基于1956—2018年31个气象站月值降水数据,采用M-K检验、Pettitt检验、Morlet小波分析、ARIMA模型等方法,分析青海省黄河流域近63年包括趋势、突变、周期在内的降水量特性以及验证未来5年降水趋势预测变化的合理性。结果表明:(1)近63年青海省黄河流域降水具有集中程度高、年内分配不均、丰枯季明显的特点;不同年代的月均降水量均集中在4—10月,且未来月均降水量有上升的变化趋势。(2)年降水量呈显著增长趋势,增长率为(9.07 mm/10 a),春季和冬季降水增长趋势显著,夏季和秋季降水无显著的增长趋势,2004年为该流域大的降水转折年。(3)年降水时间序列存在23~32 a,15~20 a,9~13 a以及4~6 a的周期变化规律,四级降水主周期分别对应30、15、11和6 a时间尺度。(4)ARIMA(2,1,4)模型能够较好地拟合1956—2018年降水序列并对2019—2023年降水数据合理预测;线性回归及M-K检验分析结果显示1956—2023年降水序列呈显著增长趋势,增长率为(9.22 mm/10 a),与趋势预测结果相一致;ARIMA(2,1,4)模型可以对青海省黄河流域进行短期年降水量预测,为当地水资源合理规划和管理提供参考。     

中国城市间金融网络的空间演化及其影响因素

基于中国金融业企业网络数据和链锁网络模型建立城市网络,在解析金融网络空间格局的基础上,定量识别与测度了金融网络的影响因素,并探讨了关键因素的作用机理。研究发现：中国城市间金融网络的中心性体系呈现空间指向和路径依赖的特征,链接关系呈现纵深关联和层级分化的特征,核心―边缘结构呈现逐渐深化和有序分布的特征;关键资源、空间距离、区位条件和历史基础是影响金融网络空间格局的关键因素;择优链接、地理邻近和空间集聚是金融网络生长发育的动力机制。在网络发展环境下,中国城市化政策需要做出相应调整,支持城市在金融网络中选择差异化的发展路径,充分发挥金融网络对城市经济增长的供给引导功能,同时在更大空间尺度上推动城市之间的网络协作。