关于下一代地震区划图编制原则与关键技术的初步探讨

本文在回顾我国四代地震区划编图原则的基础上,结合对未来我国社会经济发展状况和国家地震安全政策变化的分析,同时对国际上地震区划研究进展与编图工作的现状了解,探讨了下一代地震区划编图的基本原则,提出了与之相关的基本科学技术问题,对第五代地震区划图的编制提出了初步的建议。     

An exotic Cretaceous kimberlite linked to metasomatized lithospheric mantle beneath the southwestern margin of the Francisco Craton,Brazil

We present major and trace element compositions of mineral concentrates comprising garnet xenocrysts,ilmenite,phlogopite,spinel,zircon,and uncommon minerals (ti...     

Incorporation of GPS and IP camera for people tracking

Using the global positioning system (GPS) for people tracking continues to get easier. A person can transmit his/her GPS location from the carried mobile devices. The location is usually displayed as a dot on a digital map. However, a dot on the map is insufficient to reveal the person’s actual situation, e.g., an accident being happening. If the GPS is incorporated with an IP (Internet Protocol) camera, the camera image is critical in revealing the person’s actual situation and to improve the above-mentioned insufficient information. We present an approach to facilitate such incorporation. The approach consists of three phases: locating, tracking and monitoring collision. When the GPS coordinates of a person are within the field-of-view (FOV) of a camera, the approach enters the locating phase. The GPS coordinates are transformed to specify a candidate area (CA) in the image. The update of GPS coordinates is used to filter those moving objects within the CA until only one remains. After the person is located, he is being tracked using the shortest Euclidean distance method to find the most likely object in the next image. If the person collides with other objects while being tracked, a template matching technique, the sum of absolute difference (SAD), is used to locate the person in the collision area. The tracking is done after the person leaves the FOV of the camera. In the experimental studies, the tracking of one to three persons was performed using the implemented prototype. The average locating error of the tracking phase is only 5 pixels. The highest and average tracking success rates are 95.9% and 90.6%, respectively. These results show that the proposed approach is accurate and feasible for people tracking by incorporating GPS and IP cameras.     

深部开采保护煤柱的设计方法

为了减小或者完全避免地下开采对地表建筑物的有害影响,根据深部开采地表移动的实测数据,本文给出了地表移动和变形预计参数,利用概率积分法对地表任意点的下沉值进行计算,分析了建筑物受地下开采的影响程度,以此对矿区地表建筑物保护煤柱进行设计。研究表明,基于地表移动和变形预计理论的保护煤柱设计方法,对减少深部开采保护煤柱的压煤量、保护地表建筑物、实现地下煤炭开采的可持续发展具有一定的参考价值。     

海南国际旅游岛公众版地理信息公共平台设计与实现

简单介绍了海南国际旅游岛公众版地理信息公共平台的总体架构,再从数据集、管理服务软件系统和支撑环境三个方面分别详细介绍了平台数据内容、功能服务以及软硬件、网络部署等内容的设计与实现.     

南大洋海冰影像地图投影变换与瓦片切割应用研究

南大洋海冰分布是南极考察过程中影响破冰船航行的重要因素,也是南极研究的重要内容之一。目前国际上不同机构发布的南大洋海冰分布图,大多是球面投影,不能直接用于主流的瓦片地图发布。将极方位立体投影海冰图转换为目前主流的网络墨卡托投影地图,并利用合适的图像重采样方法,按照不同级别比例尺进行瓦片切割和编号存储,最终实现海冰影像地图的发布共享是本文的主要研究内容。笔者对不同的图像重采样方法进行了比较,分析了最邻近点采样方法、双线性内插和双三次卷积重采样方法的优劣,针对本文的研究优选双线性内插方法进行影像地图瓦片的切割,并最终叠加融合在Google地图上,实现了Google底图、准实时海冰影像图与破冰船走航位置的集成显示,为雪龙船的冰区航行提供了重要的数据支撑。     

基于旅行费用法的九寨沟旅游资源游憩价值评估

采用旅行费用法(TCM)对九寨沟世界自然遗产地的游憩价值进行评估,并对评估过程中可能存在的偏差进行分析和讨论.研究发现:九寨沟2009年的游憩价值为48.90亿元;旅行费用与旅游需求之间存在显著的负相关,而旅游需求函数的形式则以半对数模型为宜;采用工资率的1/3来计算时间的机会成本,具有一定的主观任意性,可能会导致评估结果出现偏差;用市场观测数据对旅行费用在多个目的地之间进行合理分配,可能是处理多目的地问题的所有方法中“最不坏”的一种选择;TCM与条件价值法(CVM)2种方法的评估结果相差较大,不具有良好的收敛效度,TCM的评估结果需要与更多的研究相互印证.     

Seasonally frozen soil effects on the dynamic behavior of highway bridges

Frozen ground is significantly stiffer than unfrozen ground. For bridges supported on deep foundations, bridge stiffness is also measurably higher in winter months. Significant changes due to seasonal freezing in bridge pier boundary conditions require additional detailing in order to ensure a ductile performance of the bridge during a design earthquake event. This paper reports the latest results obtained from a project that systematically investigated the effects of seasonally frozen soil on the seismic behavior of highway bridges in cold regions. A bridge was chosen and was monitored to study its seismic performance and assess the impact of seasonally frozen soil on its dynamic properties. A Finite Element (FE) model was created for this bridge to analyze the impact of seasonal frost. It was found that when frost depth reaches 1.2 m, the first transverse modal frequency increases about 200% when compared with the no-frost case. The results show that seasonal frost has a significant impact on the overall dynamic behavior of bridges supported by pile foundations in cold regions, and that these effects should be accounted for in seismic design.     

1—3月北极涛动对北半球热带太平洋和大西洋对流活动的可能影响

利用1979—2008年日分辨率的向外长波辐射资料以及NCEP再分析资料,去除ENSO影响后,分析了1—3月北极涛动对热带太平洋和热带大西洋对流活动及降水的可能影响。结果表明北极涛动偏强(弱)时,热带太平洋和大西洋对流活动显著偏强(弱)。北半球热带大洋冬季平均向外长波辐射与北极涛动指数的相关系数存在两个显著负相关区:一个位于中太平洋区,大致包括13°—20°N、160°E—170°W;另外一个位于热带大西洋,显著区覆盖的范围大体包括5°—20°N、15°—70°W。这些区域的降水量也表现出显著的正相关。向外长波辐射、强对流面积指数、强对流强度指数、平均降水量等指标与北极涛动指数的相关均以冬季同期最高,随时间滞后相关迅速减弱。与此对应的对流层低层大气环流也有显著变化,850hPa风场的变化表现为热带太平洋有异常的气旋性环流,气旋中心区与显著强对流和降水异常区一致。而热带大西洋有显著的经向环流辐合和风切变,与异常对流和降水区吻合。海洋模式的模拟结果表明,与北极涛动有关联的海温分布,很大程度上与大气强迫有关,说明热带1—3月降水和对流活动与海温的关联较弱。北极涛动与热带太平洋、大西洋对流和降水活动之间主要是通过大气环流的变动产生联系的。     

盛夏渤海湾大气边界层辐合线触发对流风暴对比分析

本文对渤海湾2008—2009年,由大气边界层辐合线引起的对流风暴进行了分析。结果表明,在高温、高湿不稳定大气层结环境条件下：（1）单一的海风锋在其端点可产生对流性降水。（2）海风锋与弱冷锋相遇,或者两条海风锋相交,或者雷暴单体的出流边界与海风锋相遇均会产生强对流风暴。（3）渤海湾边界层辐合线触发对流风暴大多发生在每年7 8月,且在副热带高压控制渤海湾后东退的过程中,此时大气层结处在高温、高湿不稳定状态。辐合线触发的对流风暴是沿辐合线移动,移动方向取决于辐合线两侧的主导风向。（4）边界层辐合线触发对流风暴,具有突发性强,持续时间短等特点,分析渤海湾边界层辐合线的移动与演变能提高强对流风暴的临近预报、预警,减少突发性天气引起的灾害。