A review of low‐cost space‐borne data for flood modelling: topography,flood extent and water level

During the last two decades, remote sensing data have led to tremendous progress in advancing flood inundation modelling. In particular, low‐cost space‐borne data can be invaluable for large‐scale flood studies in data‐scarce areas. Various satellite products yield valuable information such as land surface elevation, flood extent and water level, which could potentially contribute to various flood studies. An increasing number of research studies have been dedicated to exploring those low‐cost data towards building, calibration and evaluation, and remote‐sensed information assimilation into hydraulic models. This paper aims at reviewing these recent scientific efforts on the integration of low‐cost space‐borne remote sensing data with flood modelling. Potentials and limitations of those data in flood modelling are discussed. This paper also introduces the future satellite missions and anticipates their likely impacts in flood modelling. Copyright © 2015 John Wiley & Sons, Ltd.     

移动车载激光点云的道路标线自动识别与提取

对移动车载激光测量LandMark系统获取的路面激光点云数据进行研究,结合激光点云的回波反射率、扫描角,以及量测距离等特征信息与道路标线的属性信息,提出了一种基于车载激光点云的道路标线自动识别与提取算法。从点云中提取道路标线,采用最小二乘线性最优拟合算法对提取的标线点云进行拟合,生成道路标线的CAD轮廓线,实现道路标线的自动化识别。以移动车载LandMark系统的Sick激光扫描仪获取的路面激光点云为例进行实验,实验结果表明该方法的可行性和有效性。     

Development of BOATDSS high speed boat design database

Yachts and recreational boats have been growing in popularity throughout the world. In the United States alone they have a 2% annual growth rate. This growth has created the market for new boats built with improved hull materials and new hull forms, propulsion motors and fabrication techniques. With this growth in boat designs and technology developments, it is useful to examine the current trends in pleasure boat design. This paper addresses the development and utilization of a relational pleasure boat database BOATDSS–Boat Decision Support System. The BOATDSS database contains the data on 850 boat designs. The Decision Support System portion of the BOATDSS is organized to use this data for decision support such as a buyer shopping or a builder examining the potential of a new boat entering the present boat market. Several results from BOATDSS are presented to illustrate its use during the conception and preliminary design of recreational boats.     

艇载风压计测量平流层大气风场可行性分析

本文提出了一种基于搭载平流层飞行器对平流层大气风场进行原位探测的探测系统,并详细介绍了其工作原理、计算公式和风洞实验结果。实验室测试中,该探测系统的理论测量误差值≤2.5 m/s。在常温下的风洞试验中,该系统表现出了良好的工作性能、系统稳定性和测量准确度。在和实验室的风向、风速对比试验中的相关性均超过了0.99,风速的平均绝对偏差为0.67 m/s,风向的绝对平均偏差为2.4°。2022年,中国气象局气象探测中心利用平流层超压气球搭载该系统在海拔19 km的平流层大气中进行了原位探测试验,对所搭载平台周围的风速和风向进行了探测,并对探测结果进行了比对分析。与平台轨迹算法进行比对结果显示,该系统具有较好的一致性;与NCEP_FNL再分析数据进行比对,显示出东西向风速的相关性较好,达到了0.795,而南北风速的相关性较差,仅为0.33。试验结果表明,在平流层飞行器上搭载该探测系统可以有效地探测平流层大气风场,对于获得平流层大气环境数据集、提供大气环境预报服务、开发平流层浮空器、监测平流层飞行器周围的大气环境、规划飞行路线和区域停留等方面具有巨大的应用潜力。     

冬季黄渤海大风天气与渔船风损统计分析

选用1987-2006年NECP 500hPa高度场及海平面气压场日平均再分析资料及沿海岸基、石油平台、海岛及船舶实时观测资料,统计分析了冬季造成黄渤海海域8级和10级以上大风天气过程;选用中国渔船安全分析报告1999-2005年风灾船损事故资料,分析了大风和船损灾害的关系.结果显示:(1)冬季影响黄渤海的冷空气过程主要是来自西北路径,占全部冷空气过程的50.4%.(2)造成海上8级以上大风的冷空气过程的天气类型主要是小槽发展型112次,占全部冷空气过程的50.0%;其次是横槽转竖型61次,占全部冷空气过程的27.2%.(3)近20年冬季冷空气大风过程次数呈下降趋势;(4)风灾事故占渔船全损事故的51.85%,冬半年突发性的冷空气大风是导致木质渔船出现风灾事故的主要原因.     

2022年“龙舟水”期间华南地区降水对公路交通的影响

利用公路交通气象监测网资料、国家级公路融合降水实况分析产品及公路阻断信息,分析了2022年“龙舟水”期间华南地区的公路交通降水特点及影响特征,并对此次过程的公路交通气象服务情况进行复盘。结果表明：1）“龙舟水”期间,降水对广东、广西主要高速公路运行均产生一定影响,其中广西受严重影响的公路里程在全省路网占比高于广东。2）降水引发的公路阻断事件总体呈现出广西多于广东,北部多于南部,国省干线公路多于高速公路的特征。其中,降水对广东道路交通的影响以降雨（积水）为主,对广西的影响则以崩塌、滑坡、泥石流等次生地质灾害为主。3）华南地区公路交通降水预报落区与实况较为一致,公路气象预报预警起到了较好的预报服务效果。同时,公路交通暴雨灾害风险预估产品对于公路阻断灾情的预判体现出较好的指示意义。     

Recreational boat noise level evaluation

Recreational boats are constantly undergoing modifications and improvements in design, construction materials, and equipment. The boat builder mission is supply customers with a product with better quality, safety and onboard comfort. Onboard comfort should be evaluated along several points. Seakeeping is especially critical on long trips or operations in regions where harsh sea conditions occur. Over the years much attention has been given to boat behavior underway at sea. Recently onboard noise level has become a significant element of comfort and navigation safety. With high onboard noise a boater is unable to detect other boat whistles, horns and calls for help. This becomes a critical problem when sailing in fog and at night. Maintaining the internal noise level within limits is important. In order to address this noise problem, the paper presents a review of existing guidelines and the authors' proposal for Boat Noise Evaluation (BNE) procedure for recreational powerboats. This procedure has been used in a number of boat trials. The use of this procedure is discussed along with representative boat noise level results and a comparison with the acceptable values for passenger comfort and safety.     

面向对象的船载激光扫描数据船舶目标检测方法

提出了一种基于对象的船载激光扫描数据内河船舶目标检测方法。该方法基于船舶目标的高程信息和几何特征,利用投影和图像形态学运算方法快速确定包含船舶目标的兴趣区域;然后针对船舶目标数据的空间分布特征,对兴趣区域点云数据进行欧式距离分割和优化处理,生成实体对象,并构建高差、外包围盒和局部密度等特征构成的向量,采用支持向量机进行二元分类,提取出船舶目标。该方法成功地检测出船载激光扫描数据中的船舶目标,船舶目标检测的准确率较高。     

适用于浅海油田的高速交通艇设计

研究设计了一艘适用于浅海油田的高速交通艇，该艇采用深V线型和在侧斜螺旋浆，设有主动式减摇鳍。实船航行表明该艇具有优良的耐波性。     

20马力玻璃钢渔船的总体设计

作者为开发新型渔船并改善其性能和节约木材,设计了20马力玻璃钢渔船。船体总长Loa=13.65米,船宽B=3.40米,型深D=1.15米,平均吃水T_m=0.82米,航速V=6.5节,满载排水量为17.19吨,自持力为10天。全船采用玻璃钢材料,并设计成折角线形横剖面、延伸甲板和收缩形舭龙骨。本船稳性满足规范要求。横摇性能及适航性能良好。