地震活动多标度分形特征及预报应用

探讨了多标度分形在刻划复杂系统方面的优越性,研究了江苏及邻区1970年以来的5.5级以上地震的多标度分形特征,着重研究了地震前后多标度分形的广义维数谱和奇异性谱.研究结果表明:所有震例的广义维数谱和奇异性谱均经历了远离地震时、异常出现时和异常消失时的三个特征变化阶段;异常出现的时间在震前半年至一年半内;多数震例异常在震前几个月内回返恢复,少数在震后数个月内恢复.上述结果说明利用地震时序的多标度分形特征对于该地区的半年至一年尺度的中强地震预报是有意义的.     

Dynamic soil–structure interaction effects on the seismic response of asymmetric buildings

An approach is formulated for the linear analysis of three-dimensional dynamic soil–structure interaction of asymmetric buildings in the time domain, in order to evaluate the seismic response behaviour of torsionally coupled buildings. The asymmetric building is idealized as a single-storey three-dimensional system resting on different soil conditions. The soil beneath the superstructure is modeled as linear elastic solid elements. The contact surface between foundation mat and solid elements of soil is discretised by linear plane interface elements with zero thickness. An interface element is further developed to function between the rigid foundation and soil. As an example, the response of soil–structure interaction of torsionally coupled system under two simultaneous lateral components of El Centro 1940 earthquake records has been evaluated and the effects of base flexibility on the response behaviour of the system are verified.     

The murky waters of the second wave of neoliberalism: corporatization as a service delivery model in Cape Town

This article reviews how the process of corporatization transforms public sector management by adopting private sector principles. It argues that corporatization, as an institutional form emerging from a second wave of neoliberalism, threatens to undermine the democratic accountability of local authorities by virtue of restructuring the state in ways that are invisible to the public yet with highly negative outcomes for low-income communities. The article provides a case study on the water sector in Cape Town, South Africa by tracing the local authority's adoption of three cost-recovery policies and their impacts on low-income households over a five year period (1997-2001). Engineers are the key agents in the promotion of cost-recovery policies in the efforts to deliver services more `efficiently'. While these officials are highly skilled professionals in dealing with the technical side of the production process, they lack the social training necessary to deal with the politics of distribution. The prominence of the neoliberal agenda in urban management can be in part be attributed to the power of the technical over the political as engineers displace politicians in the deliberations over how to deliver services to poor areas of the city.     

国际服务贸易──国际贸易地理研究的新领域

国际服务贸易是战后国际贸易中发展最快的贸易形式，现已成为推动国际贸易继续向前发展的重要支柱。本文在阐明国际服务贸易的地位、构成及其地区格局的基础上，提出了国际服务贸易研究的四个基本内容。     

LMU－3型激光微量铀分析仪

ＬＭＵ－３型激光微量铀分析仪是利用激光－时间分辨技术对微量铀进行分析的一种最新型仪器。本文主要介绍该仪器的性能指标，分析方法原理和仪器整体设计原理。     

滑坡破坏时间预报新理论探讨

本文概述了当前滑坡破坏时间预报的研究水平和现状。为了完善滑坡预报方法和提高滑坡预报水平,作者从滑坡破坏的基本概念入手,提出了一种滑坡破坏时间预报的新理论,推导和确定了预报标准,比较科学地建立了预报参数,并具体地探讨了各阶段预报的预报策略及其分析处理方法。同时,还展望了滑坡动力反应及其应用研究的广阔前景。     

波速异常的进一步研究和问题讨论(三)——水库诱发地震前的Vp/Vs异常

本文研究了一些水库诱发地震前的波速比变化。结果表明:(1)在水库诱发地震(M=2-6)前均可观测到波速比异常;(2)前兆异常时间△T和震级M的关系为log△T=aM+b,其斜率明显小于天然构造地震;(3)在震级相同的情况下,水库诱发地震的波速比异常区比天然构造地震小得多。所得结果可用来区分水库诱发地震与天然构造地震,本文给出了一个具体应用实例。     

灰色系统方法在地震预报中的应用

本文利用灰色系统理论中的ＧＭ（１，１）建模法，以南北地震带不同内地域不同震级层次地震的发生时间为样本，建立了１３个预测模型，用于对未来地震的发生时间进行预报。利用其中关于５．０≤Ｍ≤５．９地震的模型较为准确地预报了１９８９年１１月宁夏固原５．０级地震的发生时间。     

时间场法在折射波资料解释应用中的研究

本文介绍的方法,对时间场法求取等时线方法进行了改进。经过理论推导,建立了便于数值计算的计算模型,并根据这一计算模型编制了FORTRAN—77计算程序。该程序不仅适用于均匀介质的情况,对地震波速度随深度变化的纵向不均匀介质等情况均适用。