IAP's Solar-Powered Unmanned Surface Vehicle Actively Passes through the Center of typhoon Sinlaku(2020)     

Hongbin CHEN  Jun LI  Wenying HE  Shuqing MA  Yingzhi WEI  Jidong PAN  Yu ZHAO  Xuefen ZHANG  Shuzhen HU 《大气科学进展》2021,38(4):538-545

The solar-powered marine unmanned surface vehicle(USV) developed by the USV team of the Institute of Atmospheric Physics is a rugged, long-duration, and autonomous navigation vessel designed for the collection of longrange, continuous, real-time, meteorological and oceanographic measurements, especially under extreme sea conditions(sea state 6–7). These solar-powered USVs completed a long-term continuous navigation observation test over 26 days.During this time, they coordinated double-USV observations and actively navigated into the path of Typhoon Sinlaku(2020) before collecting data very close to its center during the 2020 USV South China Sea Typhoon Observation Experiment. Detailed high temporal resolution(1 min) real-time observations collected by the USV on the typhoon were used for operational typhoon forecasting and warning for the first time. As a mobile meteorological and oceanographic observation station capable of reliable, automated deployment, data collection, and transmission, such solar-powered USVs can replace traditional observation platforms to provide valuable real-time data for research, forecasting, and early warnings for potential marine meteorological disasters.  相似文献   

空间直线拟合的无迭代算法   总被引：2，自引：0，他引：2  

郭际明  向巍  尹洪斌 《测绘通报》2011,(2):24-25,34

在对核电工程中一些大型构件的实际测量的数据处理过程中,经常会遇到空间直线拟合的问题.结合ObjectARX技术,提出一种拟合空间直线的无迭代算法,并在实际运用中取得良好的效果.  相似文献   

Solutions for Non‐Darcian Flow to an Extended Well in Fractured Rock     

Zhang Wen  Guanhua Huang  Hongbin Zhan 《Ground water》2011,49(2):280-285

We have investigated non‐Darcian flow to a vertical fracture represented as an extended well using a linearization procedure and a finite difference method in this study. Approximate analytical solutions have been obtained with and without the consideration of fracture storage based on the linearization procedure. A numerical solution for such a non‐Darcian flow case has also been obtained with a finite difference method. We have compared the numerical solution with the approximate analytical solutions obtained by the linearization method and the Boltzmann transform. The results indicate that the linearized solution agrees generally well with the numerical solution at late times, and underestimates the dimensionless drawdown at early times, no matter if the fracture storage is considered or not. When the fracture storage is excluded, the Boltzmann transform solution overestimates the dimensionless drawdown during the entire pumping period. The dimensionless drawdowns in the fracture with fracture storage for different values of dimensionless non‐Darcian hydraulic conductivity β approach the same asymptotic value at early times. A larger β value results in a smaller dimensionless drawdown in both the fracture and the aquifer when the fracture storage is included. The dimensionless drawdown is approximately proportional to the square root of the dimensionless time at late times.  相似文献   

广州市排水管道检测结果分析及修复技术选择     

赵巨尧  周律  安关峰  段木子  刘添俊  张洪斌  李思敏 《岩土钻凿工程》2011,(2):106-110

为确定适合广州市地下排水管道的修复方法,对广州老城区近100kin2地区进行调查。调查采用管道潜望镜（Quick View,QV）、管道闭路电视（closed—Circuit Television,CCTV）、管道声纳（Sonar）进行综合探测,结果表明,调查区域内的地下排水管道存在的主要问题是破损断裂、错位、路基下沉、管道淤塞现象,其中小直径管道的损坏情况较为严重,尤其是300mm的管道将近报废。针对地下排水管道的调查情况,结合现有修复技术的特点,经过对修复成本及施工的难易性的研究讨论,得出适合多种管道和缺陷类型的翻转内衬法（Cured In Place Pipe,CIPP）和施工要求相对简单的U型折叠法（U-fold）满足要求,并能够产生较高经济社会效益。  相似文献   

Urban land-use effects on groundwater phosphate distribution in a shallow aquifer, Nanfei River basin, China   总被引：1，自引：0，他引：1  

Jiazhong Qian  Lulu Wang  Hongbin Zhan  Zhou Chen 《Hydrogeology Journal》2011,19(7):1431-1442

Groundwater, surface water, soil and river sediment samples, and information on land use in the Nanfei River basin (NRB) of China have been analyzed to study the geochemistry, distribution, and mobilization of phosphorus. The distribution of phosphate (PO ₄ ^3??/sup> ) and the relationships between PO ₄ ^3??/sup> and several constituents in groundwater were studied. Partial correlation analysis relating PO ₄ ^3??/sup> to types of land use was conducted using the data analyzing tool SPSS 15.0. The processes controlling the transport of PO ₄ ^3??/sup> are discussed. The conclusions from this study are: (1) urban land use has obvious impact on PO ₄ ^3??/sup> in groundwater, the average concentration of PO ₄ ^3??/sup> being 4.37?mg/L, greater than that resulting from farmland and mixed land use, which have average PO ₄ ^3??/sup> concentrations of 0.10 and 0.18?mg/L, respectively; (2) the partial correlation between PO ₄ ^3??/sup> and types of land use is significant with a coefficient of 0.760; (3) the PO ₄ ^3??/sup> concentrations in surface water are generally higher than those in groundwater, and the total phosphorus (TP) concentrations in river sediments are generally higher than those in soil samples; (4) groundwater is a carrier of PO ₄ ^3??/sup> and is likely responsible for the redistribution of PO ₄ ^3??/sup> in different regions of NRB.  相似文献   

青海治多公元1374年以来树轮记录的青藏高原地面加热场强度变化     

时兴合  秦宁生  刘洪滨  汪青春  冯蜀青  刘义花 《第四纪研究》2013,33(1)

根据青海省南部玉树藏族自治州治多县629a树木年轮年表序列,依据相关等方法,分析了该年表与树木生长时气温、降水、地面加热场强度的关系.结果表明:该年表对高原年地面加热场强度反映敏感,由其重建了该区域地面加热场强度的历史序列,并应用交叉检验方法对校准方程进行了检验,证明重建方程稳定,所重建的年地面加热场强度变化比较可靠,具有一定的区域代表性.通过对重建序列的进一步分析得出,重建序列在一定程度上反映了青藏高原年地面加热场强度年际的历史变化.1374年以来在年代际尺度上,持续时间较长的年地面加热场强度特强时段有4个,即1396～1416年、1684 ～1699年、1816 ～1826年和1875 ～1889年;持续时间较长的年地面加热场强度特弱时段有4个,即1374～1384年、1417～1436年、1802～1812年和1897 ～1909年.在629a中共出现22个极端强年和8个极端弱年,15世纪出现7个极端强年和5个极端弱年.15 ～ 17世纪是年地面加热场强度的多变时期,18～20世纪是年地面加热场强度的相对稳定时段.  相似文献   

汶川地震高烈度区城镇房屋震害简介   总被引：26，自引：7，他引：19  

孙景江  马强  石宏彬  孙忠贤 《地震工程与工程振动》2008,28(3):7-15

汶川8.0级大地震宏观震中地震烈度高达X I度,造成大量房屋结构破坏和倒塌,本文介绍了极震区以及周边高烈度区内部分城镇房屋的典型震害,并给出这些城镇中砖混和底框架多层结构主要破坏等级的比例,同时对某些震害特征和相应的抗震问题进行了简要讨论。  相似文献   

A finite element solution for the fractional advection–dispersion equation     

Quanzhong Huang  Guanhua Huang  Hongbin Zhan 《Advances in water resources》2008,31(12):1578-1589

The fractional advection–dispersion equation (FADE) known as its non-local dispersion, has been proven to be a promising tool to simulate anomalous solute transport in groundwater. We present an unconditionally stable finite element (FEM) approach to solve the one-dimensional FADE based on the Caputo definition of the fractional derivative with considering its singularity at the boundaries. The stability and accuracy of the FEM solution is verified against the analytical solution, and the sensitivity of the FEM solution to the fractional order α and the skewness parameter β is analyzed. We find that the proposed numerical approach converge to the numerical solution of the advection–dispersion equation (ADE) as the fractional order α equals 2. The problem caused by using the first- or third-kind boundary with an integral-order derivative at the inlet is remedied by using the third-kind boundary with a fractional-order derivative there. The problems for concentration estimation at boundaries caused by the singularity of the fractional derivative can be solved by using the concept of transition probability conservation. The FEM solution of this study has smaller numerical dispersion than that of the FD solution by Meerschaert and Tadjeran (J Comput Appl Math 2004). For a given α, the spatial distribution of concentration exhibits a symmetric non-Fickian behavior when β = 0. The spatial distribution of concentration shows a Fickian behavior on the left-hand side of the spatial domain and a notable non-Fickian behavior on the right-hand side of the spatial domain when β = 1, whereas when β = −1 the spatial distribution of concentration is the opposite of that of β = 1. Finally, the numerical approach is applied to simulate the atrazine transport in a saturated soil column and the results indicat that the FEM solution of the FADE could better simulate the atrazine transport process than that of the ADE, especially at the tail of the breakthrough curves.  相似文献   

2008年3月30日肃南Ms5．0地震前兆异常特征研究     

朱宗德  刘鸿斌  朱振家  田洁  丁宏 《地震地磁观测与研究》2009,30(1)

对张掖中心地震台近期的前兆资料进行全面论证,并结合祁连山地震带地震活动性特征,对2008年3月30日肃南5.0级地震前兆异常特征进行研究.结果认为:此次地震的发生基本符合祁连山地震带地震活动的周期性特征,部分前兆资料有明显的短临异常显示.  相似文献   

A numerical solution for non-Darcian flow to a well in a confined aquifer using the power law function     

Zhang Wen  Guanhua Huang  Hongbin Zhan 《Journal of Hydrology》2009,364(1-2):99-106

  相似文献