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31.
Because of the special topography and large tidal range in the South Yellow Sea,the dynamic process of tide and storm surge is very complicated.The shallow water circulation model Advanced Circulation(ADCIRC)was used to simulate the storm surge process during typhoon Winnie,Prapiroon,and Damrey,which represents three types of tracks attacking the South Yellow Sea,which are,moving northward after landing,no landing but active in offshore areas,and landing straightly to the coastline.Numerical experiments were carried out to investigate the effects of tidal phase on the tide-surge interaction as well as storm surge.The results show that the peak surge caused by Winnie and Prapiroon occurs 2-5 h before the high tide and its occurring time relative to high tide has little change with tidal phase variations.On the contrary,under the action of Damrey,the occurring time of the peak surge relative to high tide varies with tidal phase.The variation of tide-surge interaction is about 0.06-0.37 m,and the amplitude variations of interaction are smooth when tidal phase changes for Typhoon Winnie and Prapiroon.While the interaction is about 0.07-0.69 m,and great differences exists among the stations for Typhoon Damrey.It can be concluded that the tide-surge interaction of the former is dominated by the tidal phase modulation,and the time of surge peak is insensitive to the tidal phase variation.While the interaction of the latter is dominated by storm surge modulation due to the water depth varying with tide,the time of surge peak is significantly affected by tidal phase.Therefore,influence of tidal phase on storm surge is related to typhoon tracks which may provide very useful information at the design stage of coastal protection systems.  相似文献   
32.
次声:监测地震的新领域   总被引:1,自引:0,他引:1  
次声现已被广泛的应用于监测领域,如监测地震、火山爆发等。相对较低的声衰减率使得次声(1~20 Hz)能够在大气中传播很长的距离。此外,从蓬勃兴起的次声台站实时传送的数据有利于我们更好地了解次声产生机制及地震的远程效应。文中着重于不同震级的地震次声波的可能产生机制,简要介绍了次声阵列的优点,给出了几个大地震的震前次声波案例,也总结了现发现的中小型地震的次声波案例,据此提出了未来的发展方向。  相似文献   
33.
为了提高软土地基沉降模型的拟合精度,通过对实测数据的分析,研究了软土地基沉降发展规律。在前人研究的基础上将Logistic预测模型和Gompertz预测模型进行叠加,建立了地基沉降历时曲线的Logistic-Gompertz叠加曲线模型,并给出模型的求解方式。通过工程实例讨论了新模型的拟合效果,对比计算结果表明所建立的新模型拟合精度不仅比Logistic模型和Gompertz模型要高,而且可靠性也优于各个单一的模型。新模型具有一定的科学性和适用性,是一种分析地基沉降观测资料的有效方法。  相似文献   
34.
将日本从北至南划分为5个区, 分析1900—2011年3月共110 a期间发生的67个Ms=6.9~9.0大震事件, 与其后4 a在中国及邻区发生的Ms≥6.0(极个别为Ms=5.5~5.8)共569个中强地震的对应比较.得出结论: (1)日本大震和中国及邻区中强震二者有很好的遥相关关系; (2)分析了日本各区与中国及邻区地震相对应的特点; (3)中国地区地震的滞后时间多为0.5~2.0 a, 最长4 a; (4)用"遥相关法"预测2011—2013年期间, 中国及邻区的中强地震危险区.年度预测与实际发生地震检验结果显示: 预测的34个次地震危险区中, "报对"28个次, 约占总预测个次的82%, "虚报"6个次, 约占18%, 显示"遥相关法"对年度地震预测有一定效果; (5)提出"蜘蛛网"逆反应模型解释中国及邻区对日本大震的响应现象.   相似文献   
35.
交通运输是创新网络中人才流、资本流等知识与技术流动的物理空间承载,其对城市的创新能力影响已成为经济地理学的交叉前沿热点。论文基于2007—2018年中国城市尺度数据,以航空和高铁运输为例,构建交通运输对城市创新能力影响效应的理论框架,采用双向固定效应面板回归模型,实证检验航空和高铁对城市创新能力的多重异质性机制,并探讨了知识传播、资本积累、产业升级在交通运输与创新能力之间的中介效应。研究发现:① 航空和高铁建设均对城市创新能力有显著正向影响,高铁对城市的创新溢出效应约为航空的3倍。② 航空和高铁对不同类型城市的创新溢出效应存在显著异质性。城市等级异质性方面,航空和高铁对中心城市创新能力的正向影响强度高于非中心城市。人口规模异质性方面,航空对大、中城市创新能力提升有显著正向影响,对小城市有抑制作用;高铁运输则对不同人口规模城市的创新能力均有正向影响,呈现大城市>中等城市>小城市的态势。区域异质性方面,航空和高铁对东、中、西、东北地区的创新能力均有不同程度的提升作用,表现出显著的“马太效应”,东部地区优势地位凸显。③ 航空和高铁均可通过促进技术转移、风险资本配置、外商资本配置间接促使城市创新能力提升。此外,航空还能够通过促进产业升级间接促使城市创新能力提升。  相似文献   
36.
多普勒雷达资料在台风探测中的应用   总被引:3,自引:0,他引:3  
苏卫东  杨维生 《台湾海峡》1998,17(4):376-383
多普勒雷达能探测到台风雨带强度图和多普勒科(台风和热带风暴,本文统称为台风)。强度的台风中心定位主要有对数螺旋垒套法和计算法;提取台风多普勒速度图的一些特征信息可对其进行定位。结合强度、多普勒速率模式定位方法可明显提高远近台风定位的准确性,文中还根据台风的气旋环流特征,利用探测到的台风中心位置和外围雨带的退模糊速度值,提出一种台风雨带风场反演方法,该方法具有一定精度。  相似文献   
37.
本文通过研究早阳金矿重点工作区构造变形现象,分析其构造变形几何学、运动学特征,区分构造活动期次,探讨与金成矿相关的构造期次。早阳金矿大地构造位置位于秦岭商丹缝合带与勉略缝合带之间,属南秦岭构造带,银杏坝-神河韧性滑脱逆冲推覆带。该金矿位于安康北部金成矿带内,为新发现的金矿床,且其控矿构造、赋矿层位、矿体围岩岩性等特征均与带内其它金矿不同。早阳金矿区构造变形复杂,经历多期构造事件叠加,发育区域性北西西向逆掩推覆、构造置换、韧性剪切带、掩卧褶皱等,与金成矿相关的构造活动为北西西向韧性剪切活动,近南北向挤压造成的北西西向脆性断裂为含金热液提供上侵通道。  相似文献   
38.
尼泊尔4·25地震震前冰湖制图与潜在危险性分析   总被引:5,自引:1,他引:4  
由于地震灾害的影响,冰湖上游的冰滑坡、冰崩、滑坡、泥石流会进入湖泊,通过冲击波或抬高水位,造成冰川坝或冰碛坝突然垮塌导致冰湖迅速排水而形成洪水或洪水泥石流.首先基于Landsat8遥感影像通过人工目视解译的方法构建尼泊尔2015年4月25日地震震前冰湖数据,为我国和尼泊尔的抗震救灾提供重要的数据支撑.然后利用历史遥感数据解译获取研究区2015年以前的历史冰湖数据,对历史冰湖数据和2015年的冰湖数据进行地理空间分析,计算其面积变化和长度变化.最后结合尼泊尔2015年4月25日地震峰值地面加速度数据通过空间分析识别地震影响区的潜在危险冰湖.研究表明:研究区面积0.02 km~2的冰湖有1 847个,面积263.18 km~2,其中快速变化冰湖87个,位于地震影响区的潜在危险冰湖49个,应重点关注潜在危险冰湖.  相似文献   
39.
Hou  Weisheng  Cui  Chanjie  Yang  Liang  Yang  Qiaochu  Clarke  Keith 《Mathematical Geosciences》2019,51(1):29-51

In each step of geological modeling, errors have an impact on measurements and workflow processes and, so, have consequences that challenge accurate three-dimensional geological modeling. In the context of classical error theory, for now, only spatial positional error is considered, acknowledging that temporal, attribute, and ontological errors—and many others—are part of the complete error budget. Existing methods usually assumed that a single error distribution (Gaussian) exists across all kinds of spatial data. Yet, across, and even within, different kinds of raw data (such as borehole logs, user-defined geological sections, and geological maps), different types of positional error distributions may exist. Most statistical methods make a priori assumptions about error distributions that impact their explanatory power. Consequently, analyzing errors in multi-source and conflated data for geological modeling remains a grand challenge in geological modeling. In this study, a novel approach is presented regarding the analysis of one-dimensional multiple errors in the raw data used for model geological structures. The analysis is based on the relationship between spatial error distributions and different geological attributes. By assuming that the contact points of a geological subsurface are decided by the geological attributes related to both sides of the subsurface, this assumption means that the spatial error of geological contacts can be transferred into specific probabilities of all the related geological attributes at each three-dimensional point, which is termed the “geological attribute probability”. Both a normal distribution and a continuous uniform distribution were transferred into geological attribute probabilities, allowing different kinds of spatial error distributions to be summed directly after the transformation. On cross-points with multiple raw data with errors that follow different kinds of distributions, an entropy-based weight was given to each type of data to calculate the final probabilities. The weighting value at each point in space is decided by the related geological attribute probabilities. In a test application that accounted for the best estimates of geological contacts, the experimental results showed the following: (1) for line segments, the band shape of geological attribute probabilities matched that of existing error models; and (2) the geological attribute probabilities directly show the error distribution and are an effective way of describing multiple error distributions among the input data.

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40.
The similarity between loess palaeo- environment and geographic distribution of modem bioclimatic zones is taken as a starting point; the relationship between the environmental aridization and soil water in loess ia discussed from the point view of the soil water energy status and their soil water physical characteristics of modem lcessial soils on the Loess Plateau. The soil water content becomes less and less from southeast to northwest, which not only provides favorable conditions for dust production by wind of loess origin, but also reveals that there is obviously a directional change in the environmental drought intensity of the Loess Plateau. Project supported by the key pmject (KZ951-B1-211) of ecological and environmental study of the Chinese Academy of Sciences  相似文献   
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