中美两国全球6级以上地震目录对比分析

中国地震台网中心(CENC)和美国国家地震信息中心(NEIC)提供的全球地震目录经常出现较大偏差.CENC发震时刻较早,CENC震源深度较深.2001年至2010年全球6.0级以上地震约11.67％存在明显目录偏差,印度洋板块北侧集中约70％有各类偏差地震.印度洋板块北侧各项误差统计占全世界同类地震约70％,表现出较好的一致性.这种现象应与震源过程有关,与该地区S波走时异常问题耦合,而不是算法或随机误差造成的.     

信息技术时代的企业区位研究(英文)

The wide application of information and communication technologies(ICTs) has been argued to be critical to spatial transformation of firms.Recent advances in the studies along this line have challenged traditional location theory.The existing literature,however,focuses mainly on the impacts of ICTs on locational conditions and industrial spatial distribution.The dynamics behind such changes have not yet been given sufficient attention by geographers.Given this background,this paper investigates the impact of new ICTs on traditional location theory and the dynamics of industrial re-location that are enabled by new ICTs,based on data collected from an investigation of 178 firms.The paper argues that the application of new ICTs has been a key location factor in the information age,and that the time-cost is becoming critical to the spatial organization of firms,particularly as a result of a shorter product life and mass customization,among other dynamics.     

Research Paper. The predictive use of GIS to model property valuations

Abstract

GIS is a technology which is ideally suited to analysis of the market values of properties, since such values are based upon spatial comparisons as well as individual property attributes. Great Britain now has a new mechanism of local taxation, the council tax, which is based upon the capital values of properties. Central to the implementation of this tax has been the potentially controversial assignment of properties to valuation ‘bands’. This paper posits that a geographical model embedded within a GIS provides an alternative means of devising credible capital values, and anticipates some of the prospects for the use of GIS in local revenue-raising.     

The Seoul of Alonso: New Perspectives on Telecommuting and Residential Location from South Korea

Although theoretical studies have contended that telecommuting could cause residential relocation to peripheral areas, empirical evidence regarding this argument is scant and inconclusive. Moreover, previous studies have given little consideration to telecommuters' job locations. Using data from the 2006 Seoul Metropolitan Area Household Travel Survey, this study investigates the relationships between telecommuting and residential location, considering job location. Regression results suggest that telecommuter households are indeed more likely to reside in outlying areas, consistent with theory. However, this does not necessarily mean that telecommuting facilitates living in outlying areas, nor, conversely, that long commutes stimulate telecommuting: causality cannot be established with these data. But contrary to both hypotheses, the result partially arises from the fact that firms allowing telecommuting also tend to be located in peripheral areas, with telecommuters having shorter commute distances compared to office workers. Consequently, issues regarding telesprawl need to be discussed considering the distribution of telecommuting-conducive occupations.     

利用小震分布和区域应力场确定临潭—宕昌断裂断层面参数

首先结合Hypo2000单事件绝对定位方法和双差定位方法时临潭-宕昌断裂附近的小震进行精确定位;然后采用模拟退火全局搜索和高斯牛顿局部搜索相结合的方法分别估算了该断裂不同位置断层面的走向、倾角、位置及相应的误差,并基于局部应力场参数反演了各断层面上的滑动角。反演的断层面走向NW-NWW,倾向NE-NEE,倾角71°~86°,滑动角102°~132°。本文给出的断层面走向、倾向和倾角与已有研究结果相似,但断层错动类型与已有结果分别为右旋走滑和左旋走滑,存在区别。初步分析认为,小震震源机制解给区域应力场参数反演结果带来了误差,进而影响了断层面上滑动角的反演误差。     

An efficient method for single-facility location and path-connecting problems in a cell map

This article presents an efficient method for simultaneously finding both the Weber cell and optimal connective paths in a grid. As numerous barriers of arbitrary shape and weighted regions are distributed in the cell map of this research, the problem scenario is similar to working out a real-life facility location selection and path-routing problems in a geographical map. In this study, the Weber problem of finding a single-facility location from an accumulation cost table is generated by a grid wave propagation method (higher-geometry maze router). After finding the Weber point (cell), optimal connective paths with minimum total weighted cost are backtracked between the Weber location cell and the demand cells. This new computation algorithm with linear time and space complexity can be integrated as a spatial analytical function within GIS.     

外资寿险公司在中国的区位分布与区位选择研究

中国的保险市场历来被国际保险业公认为是下一个最具开发潜力的市场。加入WTO以来,外资寿险公司在中国的投资进入快速扩张期,区位分布范围不断扩大。本文回顾了外资寿险公司在华发展历程,总结了其区位分布特点,并对其区位选择因子进行了实证分析。结果表明,外资寿险公司的保费收入与区域人均城镇收入水平正相关,而与区域第三产业发展水平和FDI呈负相关。未来外资寿险公司将向经济发展水平较高而市场发育程度相对较低的区域发展。     

地壳剪切波分裂研究及地震定位误差对剪切波分裂分析的影响

地壳介质的各向异性主要是由大量充满液体的微裂隙的定向排列引起的, 剪切波穿过这种含有微裂隙的介质时会产生分裂。 剪切波分裂参数与地壳介质的物理性质有关, 与区域应力场有关。 在地壳剪切波分裂研究中, 地震的定位误差对剪切波分裂参数有影响。 本文简单介绍了几种影响定位精度的因素; 并对定位误差特别是深度方向的误差所引起的时间延迟变化进行了讨论, 比较了不同大小的深度误差对归一化后的时间延迟的影响, 定量分析结果显示, 深度定位误差对慢剪切波时间延迟影响很大。 剪切波分裂分析方法有多种, 本文还对不同的剪切波分裂分析方法做了简介。     

位场垂向导数零值位置空间变化规律研究(英文)

本文推导了简单规则形体(单一边界、双边界和多边界)重力异常垂向一阶导数和重力异常垂向二阶导数零值位置的解析表达式,并研究了其空间变化规律;对难以得到其零值位置解析表达式的简单规则形体,利用其剖面图和断面图上的零值位置来研究其空间变化规律。研究结果表明,重力异常垂向二阶导数与重力异常垂向一阶导数零值位置的空间变化规律基本一致,只是重力异常垂向二阶导数零值位置比重力异常垂向一阶导数的零值位置更靠近地质体上顶面边缘位置,且其分辨能力更强。对于单边界模型,随着埋深的增加,重力异常垂向导数的零值位置均自形体上顶边缘位置向外侧偏移,但最终均能收敛于某一固定值;对于双边界模型,随着埋深的增加,重力异常垂向导数的零值位置自形体上顶边缘位置一直向外侧偏移;对于多边界模型,随着埋深的增加,重力异常垂向导数零值位置自形体上顶边缘位置向外侧收敛,部分边界的零值位置重合并消失。最后通过实际资料检验了方法的有效性和可靠性。     

隔震层位置与隔震支座选型

探讨隔震层的竖向设计位置,以期优化隔震设计,促进隔震技术的发展。隔震层设置在±0.00地板下和地下室板底相比:(1)在单层地下室部分不需设置隔震支座;(2)因减少地下室层的竖向荷载,竖向承载力的要求容易得到满足;(3)对于平面极不规则的结构,在±0.00板底隔震时,可以把上部结构分成几个平面相对比较规则的部分,因而隔震层扭转影响引起的位移可以减小;(4)对于文中算例,由于此3方面的原因,隔震支座选型后当隔震层处于±0.00地板下时可以降低隔震支座的费用达37.4%。对于平面尺寸大、平面极不规则的建筑结构把上部结构分割成若干规整的结构在首层地面以下进行隔震是一种经济可行的隔震方案。