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1.
Sea level rise threatens coastal communities throughout the United States, and South Florida is on the front line. The iconic and built-up city of Miami Beach, Florida, has a well-developed, high-value property market, and the municipality has been lauded for proactively taking action to adapt to anticipated sea level rise. Moving beyond hyperbole and piecemeal evidence, we compile a comprehensive inventory of adaptation and mitigation measures implemented by various municipal agencies. We employ these data sets to measure exposure and readiness for the entire city and make a preliminary effort to develop a city vulnerability index. Our findings reveal that exposure throughout the city is high and that readiness is concentrated near stormwater drainage systems, leading to high vulnerability along the coast. When we compare the spatial patterns of the vulnerability index and the residential property values, we find a mismatch. The most vulnerable regions are characterized by high income, transiency, and an apparent unresponsiveness to sea level rise. No doubt our findings illustrate a lag effect, but if sea level rise increases, the real estate market could reach a tipping point unless state and federal agencies also fund more comprehensive adaptation.  相似文献   
2.
中国耕地土壤相对湿度时空分异   总被引:4,自引:1,他引:3  
以全国653个农业气象站1993-2013年耕地的土壤相对湿度数据为基础,运用地统计方法,分析中国耕地土壤相对湿度时空分异特征与规律。结果表明:自1993年以来全国耕地的土壤相对湿度呈现波动上升趋势。全国耕地的土壤相对湿度普遍大于60%,分布区域自4月中旬开始随夏季风推移不断向北向西扩大,自10月下旬开始向东、南方向缩小。耕地土壤相对湿度值随土壤深度的增加而增加。年际尺度上,耕地的土壤相对湿度在夏秋季上升速度最快,变化幅度随土层深度增加而变小。土壤相对湿度与降水量存在较强的正相关关系,与潜在蒸发量、气温普遍存在较强的负相关关系。土壤相对湿度与各气象要素的相关性随深度加深而减弱。春、夏、秋季气象因素对旱地土壤相对湿度影响较大,冬季气象因素对水田影响更大。  相似文献   
3.
文章采用2005—2015年我国沿海地区的面板数据,运用数据包络分析(DEA)和随机前沿分析(SFA)方法对海水养殖技术效率进行测度,并系统分析海水养殖技术效率的影响因素和意义。研究结果表明:我国海水养殖投入和产出水平较合理,但投入资源的优化配置仍有不足;海水养殖面积、海水养殖人员数量和中间物质消耗对海水养殖产量有显著的正相关影响,投入的鱼苗数对产量的影响不显著;运用DEA和SFA方法测度海水养殖技术效率存在显著相关性和差异性,在排序上存在显著一致性;海水养殖技术水平、海水养殖结构、机动渔船比例、海水养殖产值水平和海水养殖规模与海水养殖技术效率呈显著正相关,海产品加工水平呈正相关但不显著;研究海水养殖技术效率对海水养殖产业的发展具有重要意义。最后,基于海水养殖技术效率的影响因素提出相关建议。  相似文献   
4.
外业调查与核查是获取地理国情信息的重要手段,可帮助内业解译,更好地完成工作。本文介绍了北京市地理国情监测外业调查与核查工作的具体内容,从北京市实际需求出发,研究制定了一套面向北京市的地理国情监测外业调查与核查的技术方案,保证了北京市国家基础性监测和市情专题性监测的合理有效开展,为今后地理国情常态化监测外业工作的实施提供一定的技术参考。  相似文献   
5.
Cutting performance of diamond wire saw is a key factor influencing mine planning, production scheduling, and equipment selection for dimension stone quarries. It is normally measured in terms of cutting rate. Rock samples collected from various granite and marble quarries in India were tested in laboratory to determine their physico-mechanical properties. Cutting rate of diamond wire saw was measured in the field studies during the actual cutting process in quarries. Using these laboratory determined properties and the cutting rate, a multiple linear regression model has been developed to predict the cutting rate of diamond wire saw. Physico-mechanical properties of rocks determined in laboratory are used as independent variables and cutting rate as predictor variable in the regression model. The study indicates that the cutting rate increases with a decrease in most of the hardness and strength parameters of rock. The final model is tested for its goodness of fit indicating a significant linear relation between cutting rate and physico-mechanical properties, namely tensile strength, slake durability index, and Cerchar hardness index with regression coefficient of 94%. The resulting model can be used suitably for different types of hard to medium hard and soft dimension stones. The generalized model for estimating the cutting rate becomes a handy tool for mining engineers to work out operating efficiency, expenses, planning etc. of the dimension stone block cutting.  相似文献   
6.
钻探作为获取深部地质信息的最直接手段,可查明第四纪地层序列,确定基岩顶面埋深与起伏、验证推测模型、研究地质构造、圈定地质体间的重要接触关系,服务于覆盖区填图。物探测井是一种科学有效的井内探测手段,利用特定的岩性或岩性组合对应着特定的测井参数组合的特点,利用测井参数组合可识别地层的岩性、确定地层的深度与厚度,可进行地层划分对比等。钻探-物探测井技术的综合利用,将提高覆盖区勘探效率,降低勘探成本,为下一步开展的覆盖区填图工作提供技术方法支撑。  相似文献   
7.
This paper focuses on the suitability of spring water for drinking and irrigation purposes in a part of eastern Himalaya, south Sikkim. There are many anthropogenic and geogenic factors contributing as a source of major cations and anions in the spring water. The spring water chemistry show a variation in EC, pH, TDS, Temperature, Na+, K+, Mg2+, Ca2+, Fe2+, Pb, Mn, Cu, HCO3-, Cl-, PO43-, NO3-, F- and SO42-. Mainly two types of water quality indexing has been used, one for suitability of spring water for drinking purposes and the other for irrigation purposes. For drinking purposes, Piper diagram used for determination of water type, water quality index (WQI) for quality monitoring and saturation index for mineral dissolution in water. % Na, RSC (Residual Sodium Carbon) and SAR (sodium absorption ratio) have been used for irrigation suitability. Piper diagram shows that CaHCO3 type of water was dominant in the study area. The WQI depicted excellent category and SAR, percent sodium and RSC (Residual Sodium Carbon) depict excellent, good and permissible category for irrigation purposes. Principle component analysis (PCA) was used to determine the major influencing factor responsible for the variability in the parameters analysed of spring water.  相似文献   
8.
Scattered data interpolation schemes using kriging and radial basis functions (RBFs) have the advantage of being meshless and dimensional independent; however, for the datasets having insufficient observations, RBFs have the advantage over geostatistical methods as the latter requires variogram study and statistical expertise. Moreover, RBFs can be used for scattered data interpolation with very good convergence, which makes them desirable for shape function interpolation in meshless methods for numerical solution of partial differential equations. For interpolation of large datasets, however, RBFs in their usual form, lead to solving an ill-conditioned system of equations, for which, a small error in the data can cause a significantly large error in the interpolated solution. In order to reduce this limitation, we propose a hybrid kernel by using the conventional Gaussian and a shape parameter independent cubic kernel. Global particle swarm optimization method has been used to analyze the optimal values of the shape parameter as well as the weight coefficients controlling the Gaussian and the cubic part in the hybridization. Through a series of numerical tests, we demonstrate that such hybridization stabilizes the interpolation scheme by yielding a far superior implementation compared to those obtained by using only the Gaussian or cubic kernels. The proposed kernel maintains the accuracy and stability at small shape parameter as well as relatively large degrees of freedom, which exhibit its potential for scattered data interpolation and intrigues its application in global as well as local meshless methods for numerical solution of PDEs.  相似文献   
9.
张森  石蕾  鞠楠  苏建伟 《地质与资源》2018,27(3):257-262
以"油铀兼探"的找矿思路,带动松辽盆地中南部开展砂岩型铀矿调查选区及钻探验证工作.将异常强度250 API和450 API确定为划分潜在铀矿孔、潜在铀矿化孔和正常孔的关键技术指标,对中央拗陷区南部1572个钻孔进行异常筛查工作.排查发现潜在铀矿孔362个,潜在铀矿化孔223个.对191号钻孔和36号钻孔进行钻探验证,发现1个工业孔、1个异常孔.认为区内寻找砂岩型铀矿的有利地段为油田区反转构造形成的隆起区边部四方台组河流相砂体,并总结了中央拗陷区南部6种主要控矿因素.  相似文献   
10.
Hamideh  Sara  Sen  Payel  Fischer  Erica 《Natural Hazards》2022,111(1):353-387
Natural Hazards - The 2018 Camp Fire caused significant damages to the education and healthcare systems in the town of Paradise, CA. This paper presents the findings of a qualitative case study...  相似文献   
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