Trends In U.S. Hazardous Materials Transportation Spills

This paper examines historical and spatial trends in hazardous materials transportation spills from 1971 to 1991. While the number of spills Inc.reased steadily during the 1970s, peaking in 1978–1979, there has been a decline in frequency sInc.e then largely due to modifications in reporting. Monetary damages have the opposite temporal pattern, with major Inc.reases recorded from 1982 onward. Death and injury statistics are more variable. Spatially, accidents are more prevalent in the Rust Belt extending from the Northeast corridor westward to the Great Lakes states, as well as in the Southeast. The greatest potential risk to the public is found in smaller, more densely populated industrial states such as New Jersey, Delaware, and Maryland. The spatial distribution, however, has not changed. Potential risk sources (e.g., chemical industry, number of hazardous waste facilities, number of railroad miles) are the best predictors of hazmat Inc.ident frequency. Mitigation efforts (statewide regulatory and/or management policies) also help explain the variability in hazmat Inc.idents.     

FARMING THE FOREST EDGE: VULNERABLE PLACES AND PEOPLE AROUND KIBALE NATIONAL PARK,UGANDA

ABSTRACT. Subsistence farmers near Kibale National Park, Uganda, fear and resent many wildlife species. In this article I compare records of crop damage by wildlife and livestock with local complaints about the worst animals and the most vulnerable crops. I discuss the concordance and discrepancies in complaints versus actual damage in light of physical parameters of risk and of social factors that shape perceptions and vulnerabilities. Crop losses were greatest at the edge of the forest, where immigrants are disproportionately represented. State proprietorship of wildlife amplifies local vulnerability and constrains traditional coping strategies, such as hunting.     

Unsiting Nuclear Power Plants: Decommissioning Risks and Their Land Use Context*

Nuclear power plant siting provided the first significant public opportunity to examine nuclear safety and to affect nuclear policy. These discussions were prompted and fueled by perceptions of nuclear risk. Now, as we begin the process of nuclear decommissioning, we are finding that power plant removal—unsiting–is also likely to attract public interest. This paper presents a preliminary survey of how we are likely to react to this emerging theme, applying these findings within a land use context to see if it is likely to produce issues salient to the public. In so doing it also examines how these issues could affect decommissioning timing and type. It suggests that the most likely prospect is that power plants will remain on the landscape long after they are closed.     

全国地质灾害趋势预测及预测图编制

区域地质灾害预测是地质灾害研究的难题。本文运用基于地理信息系统的风险评价方法对这一问题进行了探讨。将全国剖分为２７００个单元，对地质灾害进行现状评价，并与已数字化的地质灾害图件进行单要素叠加，编制了全国地质现状等值线图，在现状评价基础上，对地质灾害进行趋势预测，将降雨条件、区域地震活动、区域地壳稳定程度、区域岩组条件和人类工程活动等作为区域地质灾害演变的因素，运用模糊综合评判模型进行综合评判，编制了１：６００万中国地质灾害趋势预测图。     

A variance-ratio test for supporting a variable mean in kriging

This article discusses the issue of whether to use a variable mean and describes a test that can be used to evaluate whether it is justified to add terms to the drift (deterministic part) of a geostatistical model. The basic model could be the intrinsic one, where the deterministic part is a constant, and the alternate model could be any model that includes a constant term in the expression for the drift. Also, differences between constant- and variable-mean models are discussed.     

Grade estimation using fuzzy- set algorithms

This paper presents a new approach for estimating unknown ore grades within a mining deposit in a fuzzy environment using fuzzy c- means clustering and a fuzzy inference system. Based on a collection of cluster centers obtained from fuzzy c- means, a fuzzy rule base and fuzzy search domains are established to compute grades at these cluster centers. These cluter center- grade pairs act as control information in the fuzzy space- grade system in order to infer unknown grades on the basis of fuzzy interpolation, fuzzy extrapolation, and a defuzzification process of fuzzy control.     

地球物理反问题中的随机反演理论

本文从最大后验概率密度观点出发，在数据噪音向量和待求模型向量为具有零均值的独立高斯随机过程的假设前提下，建立起了随机反演的非线性系统方程；给出了模型方差估计的函数表达式，并在文章最后，证明了反演解的稀疏性，即解释了随机反演的输出解的高分辨率特征。文章在最小二乘反演方法的基础上，发展并完善了随机反演方法的理论基础；揭示了随机反演方法与最小二乘反演方法之间的本质区别；阐述了随机反演方法的优越性，并指出了其广阔的应用前景。     

Prediction of volumes and risk in hydrocarbon exploration: a quantification of geology

 The prediction of the hydrocarbon potential of a specific trap or of a number of specific traps (venture), referred to herein as prospect appraisal, concerns a probabilistic exercise based on the quantification of geology in terms of structural closure, reservoir quality, hydrocarbon charge, and the retention potential of the seal. Its objectives include: (a) prediction of the hydrocarbon volumes that could be present in the trap from an analysis of its geologic attributes; (b) the amount of uncertainty introduced in the volumetric prediction by the uncertainties in the subsurface geology; (c) the risk that one or more of the essential attributes of the prospect are underdeveloped and recoverable reserves are absent. The uncertainty of the geologic input requires a probabilistic approach, for which the Monte Carlo procedure is well suited. Prospect appraisal forms the basis for decision-making in oil exploration and development and, therefore, should be reliable, consistent, and auditable. This requires the use of a consistent methodology, the development of reliable models to quantify the geologic processes involved, and the collection of comprehensive and relational databases for the many geologic variables. As a result of data availability, uncertainty and risk tend to increase strongly from mature, producing basins to areas of frontier exploration. This may complicate management of exploration portfolios. Received: 1 July 1996/Accepted: 25 November 1996     

Early Estimation of Strong Aftershock Duration Time

In order to solve the problem of early estimation of moderately strong aftershock duration time in an earthquake sequence,this study has been conducted.First,the definition of the strong aftershock has been given.It is pointed out that there is a difference in the strong aftershock duration time between the main shock type sequence and the strong earthquake swarm sequence.After dividing the three cases,i.e.,a strong aftershock duration time larger than 1 day,smaller than 1 day,and no strong aftershock occurred in a main shock type sequence by using the pattern recognition method,we gave the rough correlation relation between strong aftershock duration time and first large shock magnitude for two types of sequences.Finally,the judgment index and method of estimating strong aftershock duration times for different sequence types have been given.     

Regionalization of unit hydrograph Parameters: 2. Uncertainty analysis

Hydrologic model parameters obtained from regional regression equations are subject to uncertainty. Consequently, hydrologic model outputs based on the stochastic parameters are random. This paper presents a systematic analysis of uncertainty associated with the two parameters, N and K, in Nash's IUH model from different regional regression equations. The uncertainty features associated with N and K are further incorporated to assess the uncertainty of the resulting IUH. Numerical results indicate that uncertainty of N and K from the regional regression equations are too significant to be ignored.