基于灰色预测理论的瓦斯传感器自校正技术

笔者提出了将灰色预测理论与单片机技术相结合 ,对瓦斯传感器的非线性进行自校正的新思路 ;采用了灰色预测理论中GM(1,1)模型和单片机技术相结合 ,将预测误差值对传感器的实测值进行分段补偿的方法 ,实现对瓦斯传感器的非线性自校正 ;该方法克服了灰色预测理论对波动较大的随机序列的预测精度低的缺陷。其研究结果表明 ,应用该方法得到的预测值与真值的拟合程度好 ,预测值与真值之间最大的差值为 0 .15 0 1% ,而该处校正前的差值为 0 .30 0 0 % ,提高了传感器的测量精度。     

Organizations in context: proposal for a new theoretical approach in prescriptive accident research

Lately, requests have been made to include the contexts of enterprises in models to prevent accidents at work. This paper presents different contextual theories in order to analyze whether this type of theory could be a way to elaborate our understanding of context. A differentiation is made between (a) theories of understanding relations between enterprises and regulatory agencies and (b) theories to perceive the relation between enterprise and the broader context. The last group of theories has its point of departure in an organizational understanding diverging from the classical, rational understanding of organizations and organizational processes. The conclusion is that contextual theories open for an elaborated understanding of the role of contextual relations in accident prevention, but also that an investigation of the potentials for making the theories action-orientated is needed.     

DEVELOPMENT AND APPLICATION OF A MODFLOW PREPROCESSOR USING PERCOLATION THEORY FOR FRACTURED MEDIA1

ABSTRACT: The discrete heterogeneity of fracture distribution and hydraulic discontinuity are the primary difficulties in the modeling of flow in fractured media. The equivalent porous medium (EPM) approach, however, which has been frequently applied to simulate flow in fractured media due to its ease of use, ignores this. This practice results in some severe limitations such as hydraulic head averaging and an inability to handle preferred fluid pathways. The PMF package (a Preprocessor to MODFLOW for Fractured media) was developed employing percolation theory to address these limitations and to utilize the simplicity of the EPM approach at the same time. This preprocessor was applied to a fractured rock aquifer around Cranberry Lake in northern New Jersey. The calibration using hydraulic head observations, validation using water balance, and evaluation using residuals show that the model generated by the PMF package can provide a superior simulation of ground water flow to the EPM approach.     

Development of a decision support system for Prioritization of multimedia dischargers

In 1990 the Environmental Protection Agency (EPA) began sponsoring several pilot projects in its regional offices to examine the potential benefits of adopting a multimedia approach to facility management. This approach differs from traditional practices at EPA in that facilities (dischargers regulated under permits issued by the agency) are managed based upon their cumulative impacts to all media: air, water, and land. Currently, facilities are managed by separate programs at EPA that evaluate environmental impacts from a single-media perspective. One aspect of discharger management is the necessity to allocate limited financial resources in a way that will minimize risk to human health and the environment. A careful, risk-based prioritization of facilities is one means of providing insight to the most effective strategy of allocating monitoring, inspection, and enforcement resources. Prioritization from a multimedia perspective is particularly difficult, however, since it requires translation and integration of medium-specific facility performances, management objectives, and perceptions of risk into a cumulative rating. A computerized decision support system (DSS) designed to guide management through the prioritization process from a multimedia perspective was identified as a potentially valuable tool for use in the pilot projects. This article describes the development of such a prototype, outlines the features of the completed system, and discusses its potential for use at EPA.     

The design and use of strategic planning arenas

This paper takes a close look at communication, process, power and institutional arrangements in the context of strategic planning. It introduces an eight step process for structuring strategic thinking and acting and develops the concept of “arenas” as a very influential — yet often very subtle — exercise of power over the course of a strategic planning process.     

EVALUATION OF CONSUMER NOTIFICATION UNDER THE SAFE DRINKING WATER ACT1

ABSTRACT: The Safe Drinking Water Act of 1974 as amended in 1986 requires that consumers be notified when maximum contaminant levels are exceeded in their community water supply and when prescribed testing and treatment procedures are not met. A review of communication theory indicates that for the message to be effective (1) it must be received by the intended audience, (2) it must be attended to by that audience, (3) it must be understood, and (4) it must be accepted and acted upon. A review and analysis of existing research evaluating notification programs administered under the Safe Drinking Water Act indicates (1) that receipt rates have been highly, variable, (2) that attention to the message has usually not been directly assessed, (3) that levels of understanding, while variable, have usually been minimal, and (4) that acceptance, though not often directly measured, seemed higher than expected. These results, while critical of past notification programs, indicate that understanding and acceptance can be increased if receipt and attention rates are increased. The paper concludes with a series of recommendations for improving receipt and attention rates, for increasing understanding, and, most importantly, for increasing acceptance and community action for upgrading local water treatment and quality.     

城市防洪堤坝适时适度维护的经济决策方法

本文应用最优控制理论，提出了城市防洪堤坝适时适度维护的经济决策模型。在一定条件下，给出堤坝最优反馈维护决策方法，并给出了一个简单的算例，说明了该法的应用和经济效益。     

海塘工程安全分析与防台抗潮决策支持技术

风暴潮期间海塘工程的安全是防汛工作的重要问题。本文对海塘工程安全的影响因素进行了分析，提出了海塘工程安全预警的思路，并将决策支持系统这一新技术引入防台抗潮的决策工作中，以提高决策人的决策能力。     

加油站定量和定性系统安全评价

论述加油站系统单元划分方法,研究加油站工艺过程,认为事故发生的原因一方面是由于系统各单元危险源的存在和控制措施的不完善,另一方面是由于工艺过程系统节点参数(流量、压力、温度等)发生有效偏差和偏差的传递造成的。针对上述两方面原因,首先从系统安全的角度,将加油站系统划分为5部分,并应用安全检查表方法对各子系统进行了定性安全评价;然后将工艺过程划分为6个节点,应用模糊危险与可操作性研究Fuzzy-HAZOP方法,对各个节点发生有效偏差的原因进行了定量的系统安全分析,并得到半定量化结果;最终从定性和定量两个方面完成了加油站系统安全评价。