日本海域9.0级地震的深刻启示与防灾减灾对策   总被引：1，自引：0，他引：1  

彭忠伟 《高原地震》2011,23(3):63-66

从日本成功的防震减灾经验中受到启示,通过详细分析日本的救灾体系、防灾减灾教育、抗震标准、灾区人口密度和应对福岛核电站问题的相关措施,提出目前我国在这些方面存在的主要问题及应对策略。  相似文献   

基于马尔科夫链的北斗行驶记录仪数据存储算法研究     

陈石平  马利滨  徐伟强 《全球定位系统》2015,(3)

介绍了北斗行驶记录仪的组成和功能,对定时1 s和定时60 s报送或存储进行了对比和优劣分析,根据道路匹配特性,给出了一种基于马尔科夫链的北斗行驶记录仪数据存储算法,将马尔科夫链上的节点（拐点）作为记录仪存储或传输的位置点,通过采集车辆状态信息和定位模块输出信息对“拐点”计算方法进行分析和推导,并通过多次实际跑车测试,测试结果表明：与定时1 s报送或存储相比,节省率可达到90％以上,大大节省了存储空间或者通信费用,具有较好的使用效果。  相似文献   

中国省域离婚率的时空格局及趋同演变研究   总被引：1，自引：0，他引：1  

白彩全  陈昶  丁一帆  吴启焰 《测绘科学》2015,(11):48-53

针对现有离婚率研究时间、空间割裂,整体性探讨不足及实证研究缺乏的问题,该文运用空间自相关、空间马尔可夫链等空间统计方法对中国大陆各省域1979—2012年离婚率数据的时空分布及趋同演变进行了研究,结果发现:除东北、西北地区离婚率一直居高不下之外,中国大陆高离婚率地区逐步向中部延伸并聚集,离婚率存在着较强的空间自相关且空间聚集现象明显;省域离婚率的"两极分化"现象和"俱乐部趋同"现象均经历了由弱到强再减弱的波动变化趋势。  相似文献   

气候变化对中国农业旱灾损失率的影响及其南北区域差异性   总被引：4，自引：1，他引：3  

张强  韩兰英  郝小翠  韩涛  贾建英  林婧婧 《气象学报》2015,73(6):1092-1103

在全球变暖背景下,干旱灾害对中国农业生产的影响日益严重,然而由于旱灾损失的复杂性及其显著的区域差异,至今对中国农业旱灾损失规律及其影响机制的认识十分有限。文中利用1961年以来中国农业干旱灾害的灾情资料和常规气象资料,系统分析了近50年来中国农业干旱灾害不同受灾强度分布比率和综合损失率等指标的变化趋势及其在北方和南方的区域差异,研究了20世纪90年代的气温突变对农业旱灾损失率的影响特征,探讨了农业旱灾综合损失率对气温和降水等气候要素变化的依赖关系及其在气候空间的分布特征。结果发现,在气候变化背景下,近50年来中国农业旱灾综合损失率平均每10 a约增加0.5%,风险明显增大。而且,北方综合损失率每10 a约增加0.6%,高出南方1倍,风险增大的速度明显比南方快;北方农业旱灾几乎在很宽松的气温条件下就可以发生,而南方更多发生在气温较高的年份。并且,在气温突变后,变化趋势明显加剧,全中国综合损失率约增加了0.9%,风险明显增高;而且北方综合损失率的增值高达1.8%,是南方的4倍还多,气候突变对北方农业旱灾风险的影响明显比南方更凸出。综合损失率在北方对降水变化的响应要更敏感,而在南方对气温变化的响应更敏感。同时,关键影响期降水对综合损失率的影响比全年降水影响更显著;北方的关键影响期作用比南方更凸出。这些新的科学认识对中国农业旱灾防御具有重要意义。  相似文献   

台风“苏力”灾害风险与防御行为效益评估     

杨林  曹春荣  林秋  明章  林文华  赵珊珊 《气象与环境学报》2015,31(1):106-112

利用2013年台风“苏力”的监测资料、台风灾情资料、2000年后福建省台风灾害数据库资料和台风“苏力”灾害防御行为效益评估网络问卷调查资料,采用相似分析法的上下限区间估算法,预评估台风“苏力”造成的受灾人口和直接经济损失,并利用台风灾害风险区划方法,对台风“苏力”进行灾害风险区划。结果表明：台风“苏力”预评估结果与实际灾情相符,台风“苏力”灾害风险分布与实际灾情分布大部分一致,风险等级高的县市,实际灾情重,高风险区的大部县市直接经济损失均为1000万元以上。应用台风灾害防御行为效益评估三级指标体系,通过调查统计分析可知,指标体系中的各级各项指数均能较好地反映和评估政府主导、部门联动和公众参与的防御行为效益,政府主导在各类减灾行为中作用最大。  相似文献   

A tool for ROV-based seabed friction measurement     

《Applied Ocean Research》2015

This paper describes a new device for measuring seabed sliding resistance in situ, and provides an associated interpretation procedure. The device is designed to use a work class ROV as a testing platform to allow measurements to be obtained without use of a specialized geotechnical survey platform. The measurements are to assist pipeline design or analysis of the sliding resistance of other on-bottom infrastructure such as anchor chains. The device has been trialled using three tools: a flat plate, a cylindrical pipe section and a length of chain. The tools are dragged axially along the seabed using the ROV thrusters or a separate hydraulic actuator. An interpretation technique has been developed to estimate the passive resistance mobilized by the faces of the tools to eliminate end effects and to account for shape effects such as wedging. Onshore-trial tests were performed in a bed of dry sand. The individual tools exhibited different overall coefficients of friction, but the back-analysis method yielded equal interface friction angles acting on all three devices, indicating internal consistency. The interface friction angle also matched shear box test results. These outcomes confirm the correct operation of the device in drained seabed conditions, and yield useful information on the sliding resistance of pipes and chains. In addition, the back-analysis method allows measurements from one shape of tool to be used to estimate the response of other objects.  相似文献   

应用实时定量PCR技术检测秦皇岛近岸海域褐潮原因种——抑食金球藻(Aureococcus anophagefferens)     

GUO Hao  LIU Yongjian  ZHANG Qi  YUAN Xiutang  ZHANG Weiwei  ZHANG Zhifeng 《海洋学报(英文版)》2015,34(2):132-136

Aureococcus anophagefferens, a small pelagophyte algae, has caused brown tide blooms in coastal waters of Qinhuangdao in recent years, presenting significant negative impacts on the shellfish mariculture industry. Under standard light microscopy, it is visually indistinguishable from other small algae in field samples due to its extremely small size. In this study, quantitative polymerase chain reaction(q PCR) based on 18 S r DNA sequences was developed and used to detect and enumerate A. anophagefferens. A linear regression(R2 = 0.91) was generated based on cycle thresholds value(Ct) versus known concentrations of A. anophagefferens. Twenty-two field samples collected in coastal waters of Qinhuangdao were subjected to DNA extraction and then analyzed using q PCR. Results showed that A. anophagefferens had a wide distribution in coastal waters along Qinhuangdao. Elevated A. anophagefferens abundance, category 3 brown tide blooms(200 000 cells/m L) occurred at Dongshan Beach and Tiger-stone Beach in August in 2013. In shellfish mariculture areas along coastal waters of Qinhuangdao, 4 stations had category 3 blooms, and 6 stations had category 2 blooms(35 000–200 000 cells/m L) in August and all stations had category 1 blooms(0 to ≤35 000 cells/m L) in October. Quantitative PCR allows for detection of A. anophagefferens cells at low levels in filed samples, which is essential to effective management and prediction of brown tide blooms.  相似文献   

Precious corals become more precious in the northwestern pacific: Urgent need for integrated policy     

《Marine Policy》2015

The limited precious coral (Coralliidae) resources in the Northwestern Pacific have been managed by Taiwan with a comprehensive management plan, by Japan with a strengthened set of management measures, and by China through the listing of such coral as a Category I national treasures. However, continuous increases in coral consumption and coral prices have stimulated overexploitation and poaching of the resource, and hence have undermined the effectiveness of these management schemes. This article discusses the current precious corals supply chain and suggests that the rise of China in purchasing substantial amounts of coral products was the underlying cause for overexploitation and poaching. Several gaps in the management schemes are also identified and discussed. The article finally concludes that there is an urgent need for establishing a cross-disciplinary integrated conservation policy and a regional management platform consisting of the three participating states to address all the relevant social and ecological issues.  相似文献   

空间分类在连锁超市选址中的应用研究     

杨莉  周志富 《测绘与空间地理信息》2011,34(5):148-151,155

空间数据挖掘是一种知识决策支持技术,本文以大型综合连锁超市为例,研究了空间分类挖掘方法在连锁超市选址预测中的应用问题。结合连锁超市定位理论,对实验数据进行了选择和处理。同时进行了基于关联的分类实验,得到指导和预测选址的知识,并对预测知识的准确性和可信度进行了检验,结果显示预测准确率和可信度较高。本文制定的挖掘方案可为连...  相似文献   

A Comparison of Four Precipitation Distribution Models Used in Daily Stochastic Models     

LIU Yonghe  ZHANG Wanchang  SHAO Yuehong  ZHANG Kexin 《大气科学进展》2011,28(4):809-820

Stochastic weather generators are statistical models that produce random numbers that resemble the observed weather data on which they have been fitted; they are widely used in meteorological and hydrologi- cal simulations. For modeling daily precipitation in weather generators, first-order Markov chain-dependent exponential, gamma, mixed-exponential, and lognormal distributions can be used. To examine the perfor- mance of these four distributions for precipitation simulation, they were fitted to observed data collected at 10 stations in the watershed of Yishu River. The parameters of these models were estimated using a maximum-likelihood technique performed using genetic algorithms. Parameters for each calendar month and the Fourier series describing parameters for the whole year were estimated separately. Bayesian infor- mation criterion, simulated monthly mean, maximum daily value, and variance were tested and compared to evaluate the fitness and performance of these models. The results indicate that the lognormal and mixed-exponential distributions give smaller BICs, but their stochastic simulations have overestimation and underestimation respectively, while the gamma and exponential distributions give larger BICs, but their stochastic simulations produced monthly mean precipitation very well. When these distributions were fitted using Fourier series, they all underestimated the above statistics for the months of June, July and August.  相似文献