Integrating economy, ecology and uncertainty in an oil-spill DSS: The Prestige accident in Spain, 2002   总被引：1，自引：0，他引：1  

Kai W. Wirtz  Xin Liu 《Estuarine, Coastal and Shelf Science》2006,70(4):525

Major accidental oil spills still affect sensitive marine areas and shorelines around the world, constituting a challenge for operational as well as strategic contingency management. As a rationale basis for addressing both issues we here propose a Decision Support System (DSS) consisting of a combination of modelling and evaluation methods which in particular assesses various impacts on habitats and local economies. By integrating the state-of-the-art oil spill contingency simulation system OSCAR with wind and current forecasts, environmental GIS data and multi-criteria analysis techniques, the DSS is able to rank different response actions to a chemical or oil spill. In this study, the usefulness of the approach is tested by hindcasting the Prestige accident off the coast of Spain in 2002. In particular, the short- to mid-term economic and ecological consequences of different mitigation measures are estimated. We identified clearly one worst option matching the actual decision taken by the responsible parties and one or two almost equally well performing routes. Two procedures of including uncertainty at various stages of the DSS are tested. The first method averages ensembles of outcomes between each modelling/evaluation stage, while the second one preserves the entire degree of freedom till the final ranking procedure. Results in the Prestige case turned out to be rather insensitive against both ways to account for uncertainties. The robustness as well as clarity of the DSS has the potential to enhance the efficiency of decision making even in politically sensitive situations. Limitations as well as ongoing improvements of the system are highlighted, in particular emphasizing linkages to environmental economics.  相似文献   

Forced vibration analysis of an offshore tower carrying an eccentric tip mass with rotary inertia due to support excitation     

Jong-Shyong Wu  Chin-Tzu Chen 《Ocean Engineering》2007,34(8-9):1235-1244

Dynamic responses of structures due to earthquake excitation are the important problems in engineering, thus, the information concerned is plenty. However, most of the literature is relating to the discrete methods, particularly to the finite element method (FEM), and the one relating to the method combining both the “continuous” and “discrete” models is rare. The objective of this paper is to provide some information in this respect. First, the analytical solution for the natural frequencies and normal mode shapes of a “continuous” tower, without contacting water (or “dry” tower), carrying an eccentric tip mass possessing rotary inertia is determined. Next, the partial differential equation of motion for the forced vibration of the tower, contacting water (or “wet” tower), subjected to support excitation is transformed into a matrix equation by using the last natural frequencies and normal modes shape of the freely vibrating dry tower. Finally, the numerical integration method is used to solve the matrix equation to yield the seismic response of the wet tower. In theory, the mode superposition method is correct only if the total number of modes considered approaches infinity, however, numerical results of this paper reveal that superposition of only the lowest six modes will yield excellent results to be very close to the corresponding ones obtained from the conventional FEM. For this reason, the CPU time required by the presented approach is less than 5% of that required by the conventional FEM.  相似文献   

Reconstruction and prediction of the total solar irradiance: From the Medieval Warm Period to the 21st century     

《New Astronomy》2015

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基于超宽带雷达及支持向量机的灾后人体呼吸信号识别方法与试验研究     

樊哲宁  朱嘉健  王立新  杜鹏  张移  谢海珠 《震灾防御技术》2021,16(3):597-604

与常规雷达相比,超宽带雷达具有距离分辨力高、近距离盲区小、穿透性强、目标识别率高等特点,已被广泛应用于灾后搜寻、救援工作中,以对受困生命体征目标进行生命探测。为实现使用超宽带雷达对受困生命体征目标的识别定位,本研究提出基于信号多特征提取技术及支持向量机模型的人体呼吸信号识别方法。首先,使用经验模态分解、变分模态分解及希尔伯特变换提取雷达探测信号的微多普勒特征,使用傅里叶变换提取宏观频谱特征,使用相关分析获取相关性特征;然后,以提取的信号特征为输入,使用支持向量机模型对信号进行分类,进而对人体呼吸信号进行识别,对人体位置进行定位。不同障碍物场景下的试验结果表明,本方法可有效识别砖墙、建筑楼板等遮挡物下的受困生命体征目标,并提供其位置信息。  相似文献   

基于SVDD的变形监测数据可靠性分析研究     

彭磊  贾莹媛  杨富春  杨志文 《北京测绘》2012,(1):12-14,4

提出了一种基于支持向量数据描述的异常值检测方法,该方法在检测异常值方面具有快速形象、通用性强、可有效处理小样本数据等优点。实验结果证明当在训练样本中加入异常值时,训练得到的模型具有很高的正常数据识别率和异常数据识别率,因此,该方法用于异常值的检测是完全可行的。  相似文献   

Building Environmental Literacy through Participation in GIS and Multimedia Assisted Field Research     

《The Journal of geography》2012,111(1):10-19

Abstract

A Learning Support System (LSS) that emphasizes experiential research in natural environments using the cutting-edge technologies of GIS and multimedia has been developed for teaching environmental literacy to undergraduate students at the University of Georgia. Computers are used as cognitive tools to create a context in which students become interns in an ecological research center. Students are instructed to conduct research in the form of two field laboratories (the stream and forest laboratories). They accomplish their tasks by collecting data in the field (the State Botanical Garden of Georgia near the campus). They enter the data in the Learning Support System (LSS), and are guided to formulate hypotheses relating to stream water quality and human impact on forest succession for testing. Students also interact with the Environmental Research Support Site (ERSS) within the LSS for explanations to their findings. A specially customized Arc View GIS program within the LSS provides a tool to students for spatial analysis in the case of the forest laboratory. Students and faculty evaluations as well as final examination results confirmed the receptiveness of students to the LSS approach and its effectiveness in the learning of environmental literacy.  相似文献   

秸秆焚烧导致湖北中东部一次严重霾天气过程的分析   总被引：1，自引：0，他引：1  

周悦  岳岩裕  李兰  刘敏  周婷 《气候与环境研究》2016,21(2):141-152

利用地面气象要素、火点信息及污染物资料,研究了2014年6月12~13日湖北省中东部地区一次重度霾天气的成因及污染特征。结果表明:导致此次霾天气的主要原因是安徽省北部大面积秸秆焚烧所形成污染气团受偏东北气流输送的影响,12日在湖北中东部形成了两条"带状"的能见度低值区,最低能见度仅为2.1 km。秸秆焚烧污染物输送气流由北向南影响湖北,主要作用于孝感—武汉—咸宁一带,3个地区细颗粒物(PM2.5)峰值浓度均超过了600μg/m3,且武汉和孝感的PM2.5与PM10质量浓度比值在12日增加到0.76和0.77,并出现了0.96和0.93的最大值,随着污染气团的传输,其中PM2.5所占比例会出现明显下降。SO2质量浓度的变化特征不显著,NO2质量浓度在污染物质量浓度达到峰值前1~3 h达到峰值,而CO是秸秆焚烧产生的主要污染气体,其质量浓度变化与PM2.5和PM10呈正相关关系,相关系数分别为0.66和0.67。风矢量和分析表明:6月12日湖北省中东部存在明显的东北来向气流输送,污染物的输送是该时段霾天气发生的主要影响因子,而6月13日湖北省东北边界处的输送气流已经明显减弱消失,东南部风矢量和异常偏小导致的污染物堆积是该地区污染持续的主要原因。  相似文献   

基坑土钉墙支护施工工艺探究     

于宁 《城市地质》2010,5(4):45-48

土钉墙作为一种比较实用的原位岩土加固技术,近年来在深基坑支护工程中得到了广泛的应用。本文简要阐述了基坑土钉墙支护施工的主要步骤及相关技术,分析了深基坑土钉墙支护主要施工工艺。  相似文献   

利用风廓线雷达资料分析大理机场飑线天气过程的风垂直变化特征     

王周鹤  赵建伟 《沙漠与绿洲气象(新疆气象)》2020,14(2):75-80

飑线天气现象是航空气象中危险和复杂的天气现象之一,2018年大理机场出现两次飑线天气过程,利用风廓线雷达资料和航空气象地面观测资料,分析两次飑线天气过程的风垂直变化特征。结果表明:(1)在飑线天气过程开始前2～4 h,从底层到高层均出现明显的上升运动,飑现象开始前后,上升运动和下沉运动同时存在,为大气中垂直热交换过程提供了有利条件;(2)飑线天气过程存在垂直风的水平切变及垂直切变,反映了强烈的对流发展,发展到离地高度5000 m以上;(3)飑线天气过程存在径向速度突变增大、谱宽变宽和单波束径向速度折叠现象,说明本场出现的是风雨交加的强对流天气;(4)高空到地面存在湍流运动,能量交换频繁,气流紊乱。  相似文献   

Evaluation of the parameters affecting the roughness coefficient of sewer pipes with rigid and loose boundary conditions via kernel based approaches     

《国际泥沙研究》2020,35(2):171-179

One of the important issues in water transport and sewer systems is determining the flow resistance and roughness coefficient.An accurate estimation of the roughness coefficient is a substantial issue in the design and operation of hydraulic structures such as sewer pipes,the calculation of water depth and flow velocity,and the accurate characterization of energy losses.The current study,applies two kernel based approaches [Support Vector Machine(SVM) and Gaussian Process Regression(GPR)] to develop roughness coefficient models for sewer pipes.In the modeling process,two types of sewer bed conditions were considered:loose bed and rigid bed.In order to develop the models,different input combinations were considered under three scenarios(Scenario 1:based on hydraulic characteristics,Scenarios2 and 3:based on hydraulic and sediment characteristics with and without considering sediment concentration as input).The results proved the capability of the kernel based approaches in prediction of the roughness coefficient and it was found that for prediction of this parameter in sewer pipes Scenario 3 performed better than Scenarios 1 and 2.Also,the sensitivity analysis results showed that Dgr(Dimensionless particle number) for a rigid bed and w_b/y(ratio of deposited bed width,w_b,to flow depth,y) for a loose bed had the most significant impact on the modeling process.  相似文献