基于PMC方法分析北京及邻区地震监测能力

1 研究背景 北京及邻区(39 °—41.5 °N,115 °—118 °E)地震活动背景活跃,政治、经济、文化高度集中,是我国经济社会发展以及减轻地震灾害的重点监视区之一(徐锡伟等,2002;陈颙等,2006).随着北京及邻区地震台网组成的不断完善和台站变更频度的加快,亟待及时动态评估地震监测能力变化,为北京及邻区日常监测预报业务提供数据支撑.国内外应用广泛的"基于概率的完整性震级"(probability-based magnitude of completeness,简称PMC)方法(Schorlemmer and Woessner,2008;Schorlemmer et al,2010),基于地震台阵/地震台网实际产出的观测资料,可实时、客观、准确地评估地震台网监测能力.采用PMC方法,对北京及邻区地震监测能力进行动态评估,以便摸清该区监测能力,进而为防震减灾部署、监测预报相关业务开展等提供重要的参考资料.     

广东省惠东县地质灾害发育特征及形成条件

通过开展惠东县地质灾害调查与成灾规律研究,对惠东县地质灾害发育特征与分布规律进行总结,并详细分析惠东县地质灾害形成条件,结果表明：惠东县地质灾害类型多,且具有分布不均、局部集中的特点。地质灾害发生时间主要集中在5—9月,且8月份为地质灾害高发期。空间上,地质灾害主要分布在宝口镇、高潭镇、白盆珠镇。地质灾害点多沿断裂构造或褶皱构造大致呈线性分布,在区域性大断裂与其次生断裂的交汇处地质灾害点分布更为密集。在岩性组合上,地质灾害主要分布在层状较软-较硬碎屑岩组中,其次为块状较硬-坚硬侵入岩综合岩组。在地形地貌上,20°～50°坡度范围内的斜坡最易发生滑坡,40°～80°坡度范围内最易发生崩塌。人类工程活动、降雨为地质灾害最主要的诱发因素,地质灾害大多与城乡建设中的削坡建房有关,在强降雨期间或雨后一天,地质灾害较为易发。     

分布式地理数据库同步更新系统设计与实现

分散且分割的基础地理数据已越来越不能满足数字城市建设的需求,为提高基础地理数据的连续应用服务能力,需实现分布式地理数据的同步更新。研究分布式地理数据库的数据复制、同步技术和更新冲突处理算法等关键技术,设计分布式地理数据库同步更新系统,实现以宁波市市级数据库为主库、区级数据库为副库的分布式数据库的集中管理和分布更新的同步机制。     

GPS RTK结合测量机器人在高铁CPⅢ网建设中的应用

提出了一种GPS RTK技术与TCA2003测量机器人技术相结合实施CPIII控制网测量的技术方案。通过具体工程试验表明,在满足测量精度的前提下,可有效地提高外业测量的作业效率。     

甘孜州九龙县水土流失评价研究

本文以九龙县为研究区,根据沟壑密度、坡度、植被盖度、土地利用类型和高程5个因子,结合ARC-GIS空间分析功能和MATLAB数学建模编程的功能,应用GA-BP模型(遗传算法优化BP神经网络)对研究区的水土流失进行非线性智能定量评价,并与层次分析法的结果对比分析,阐述了GA-BP模型的优越性。本次研究可以为九龙县水土流失预防和治理提供有益的参考。     

我国农民收入时空差异的地域与因子结构双重解析

根据泰尔系数和基尼系数可按地域和收入来源进行分解的特性,对我国1997—2009年间各省份农民收入时空差异进行地域和因子结构双重解析。结果表明,省际间农民收入呈小幅波动增大态势;三大地带内差异是构成农民收入差异的主导部分,尤其是中部地带内省际间差异和贡献居首要地位;因子结构分解则显示工资性收入对总体非均衡程度的贡献最高。着力加快中、西部地区的工业化、城镇化进程,推进农业剩余劳动力向城镇转移或向非农产业转移,提升其工资性收入水平,并从政策、财政和科技等方面支持落后地区加快发展家庭经营是缓解农村地区省际收入差距并促进农村经济区域协调发展的有效途径。     

紫色土坡面水流跌坑形态特征及其成因

跌坑的形成是坡面侵蚀过程中的重要一环,是细沟开始出现的临界形态,跌坑的贯穿标志着细沟的形成。本研究采用模拟降雨与微地形测量相结合的方法,调查了不同雨强下紫色土坡面跌坑的发育过程及其形态分布。试验结果表明,降雨初期紫色土坡面水流跌坑边界模糊,横断面上跌坑基本在相同水平线上,与紫色土颗粒组成较粗有关;1.83～2.33 mm/min的雨强下,顺坡跌坑平均间距变化于8.2～9.4 mm之间,跌坑深度顺坡分布呈现较大的波动性,平均深度介于1.4～1.8 cm,总体上随雨强呈增大趋势;横断面上跌坑宽度变化相对较大,平均宽度介于9.4～16.3 cm,随雨强变化趋势不明显;跌坑水平间距除边界外相对稳定,地势低洼处优先形成跌坑,但也并非尽然;基于运动波理论分析认为,紫色土坡面跌坑的连续分布是坡面流运动波的能量周期性波动作用形成。     

MRICES:一个新的减排方案评价模型及其应用(英文)

Many global emission reduction strategies have been proposed, but few have been assessed quantitatively from the view of equality, efficiency and effectiveness. Integrated assessment models (IAM) is one of the effective ways to make climate policy modeling. So in this paper we developed the MRICES (Multi-regional integrated model of climate and economy with GDP spillovers) model, which is an IAM but extends to include GDP spillover mechanism, to make assessment on several strategies for global emission reduction, including the egalitarianism strategy, the UNDP strategy and the Copenhagen Accord. Using 1990 as a baseline for historical emission levels, the egalitarian strategy argues that developed countries should implement urgent emission reductions, whereas developing countries are allowed relatively higher future emission quotas. The UNDP strategy addresses the issue of substantial changes in global temperature but acknowledges that developing countries are not able to afford more costs for mitigation measures, which is inequitable from the perspective of a country’s right to develop. We also simulated the Copenhagen Accord to determine the consequences by the year 2100 if each country continues their current emission mitigation actions, and results indicated that the increase in global temperature will be 2.8 ℃by 2100; consequently, much stronger emission reduction efforts must be implemented after 2020. Based on analysis on mitigation strategies, it is recognized that the common but differentiated responsibility principle must be insisted when making global mitigation strategy. To comply with this principle, the emission reduction baseline of developed and developing countries should be discriminated, so 1990 and 2005 can be taken as the base year for developed and developing countries respectively.     

ANALYSIS OF THE WESTWARD EXTENSION OFWESTERN PACIFIC SUBTROPICAL HIGH DURING A HEAVY RAIN PERIOD OVERSOUTHERN CHINA IN JUNE 2005

The NCEP/NCAR II daily mean reanalysis data and observed precipitation data are employed to investigate the westward extension of the western Pacific subtropical high (WPSH) during the heavy rain period over the southern China in June 2005. Results show that there may exist a relationship between the east-west shift of the WPSH and the process of a southern China heavy rain. The analysis indicates that the vertical motion in the WPSH area is mainly caused by the latent heat release of monsoon rain belts on its northern and southern sides. The vertical motion could cause the accumulation of air mass in the center and west of the WPSH, which leads to its strengthening. The appearance of the northern and southern monsoon rain belts could not only enhance the WPSH by strengthening the descending draft, but also excite the development of positive vorticity and restrict the WPSH’s movement in the north–south direction. Moreover, the Indian monsoon rainfall to the west of the WPSH may excite the development of anticyclonic vorticity on its eastern side, which leads to the westward extension of the WPSH.     

VARIATION FEATURES OF SOMALI CROSS-EQUATORIAL FLOW AND ITS IMPACT ON THE LOCATION OF THE SUBTROPICAL HIGH RIDGE FROM JULY TO SEPTEMBER

The variation features of the cross-equatorial flow and its impact on the ridge position of the subtropical high have been analyzed in this paper. It is shown as follows. (1) The intensity of the Somalicross-equatorial flow is increasing in winter and summer in the past 44 years and the airflow of Northem Hemisphere exchanges more and more intensively with that of Southern Hemisphere. (2) The Somalicross-equatorial flow in May has the most impact on the ridge position of the subtropical high in the typhoon season, presenting a positive correlation. (3) The diagnosis is consistent with the real situation in 2005.