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781.
Ben Beardmore 《Journal of the American Water Resources Association》2015,51(2):537-549
Understanding public perceptions of the importance of environmental issues is crucial for gauging support for management activities. I present a novel methodological approach to assess the importance boaters placed on 16 water issues in a lake‐rich region of northern Wisconsin. A latent class maximum difference conjoint model was used to examine the relationships between environmental concern and engagement with lake resources. Boaters were grouped to maximize observed heterogeneity in prioritizing issues of concern. Socio‐demographic characteristics, recreation specialization, place attachment, and attitudes concerning aquatic stewardship and invasive species management were then used to predict class membership. This modeling approach identified five groups whose perceptions of issues pertaining to lakes are influenced by their interactions with the lake environment. While anglers were most concerned about fishing quality, sightseers identified lakeshore development and loss of natural habitat. Groups also differed in their socio‐demographic and attitudinal characteristics. The priorities of each group were substantially different from those of the overall sample. Accounting for differences in stakeholders' environmental concerns may improve public involvement in water management initiatives by allowing managers to identify common concerns and prioritize important issues among multiple groups. 相似文献
782.
783.
Failure of Leak Detection System (LDS) to detect pipeline leakages or ruptures may result in drastic consequences that could lead to excessive financial losses. To minimize the occurrence of such failure, the functionality of the LDS and the integrity of the pipeline should be assessed on a priority basis. This paper presents an integrated risk-based assessment scheme to predict the failure and the failure consequences of offshore crude oil pipelines. To estimate risk, two important quantities have to be determined, the joint probability of failure of the pipeline and its LDS and the consequences of failure. Consequences incorporate the financial losses associated with environmental damage, oil spill cleanup and lost production. The assessment provides an estimate of the risk in monetary value and determines whether the estimated risk exceeds a predefined target risk. Moreover, the critical year for the asset can be determined. In essence, the outcome of the assessment facilitates an informed decision-making about the future of the asset. 相似文献
784.
Conveyor belt fires in an underground mine pose a serious life threat to miners. Water sprinkler systems are usually used to extinguish underground conveyor belt fires, but because of the complex interaction between conveyor belt fires and mine ventilation airflow, more effective engineering designs are needed for the installation of water sprinkler systems. A computational fluid dynamics (CFD) model was developed to simulate the interaction between the ventilation airflow, the belt flame spread, and the water spray system in a mine entry. The CFD model was calibrated using test results from a large-scale conveyor belt fire suppression experiment. Simulations were conducted using the calibrated CFD model to investigate the effects of sprinkler location, water flow rate, and sprinkler activation temperature on the suppression of conveyor belt fires. The sprinkler location and the activation temperature were found to have a major effect on the suppression of the belt fire, while the water flow rate had a minor effect. 相似文献
785.
The arrangement of components plays a key role in the performance of complex Safety Instrumented Systems (SIS), in which a SIS logic solver is interlocked with other logic solvers, to share a final element, for instance. The position of the components and the way they are utilized affects the reliability characteristics, such as the Probability of Failure on Demand (PFD), Spurious Trip Rate (STR), architectural sensitivity and model uncertainty. This case study uses quantitative and qualitative approaches to elaborate on various aspects of component arrangement in complex SIS. Numerous simplified models are analyzed; new classification is introduced for SIS components based on their response to demand; a set of guidelines are developed for SIS architecture design, with a focus on component arrangement; and the use of these guidelines is demonstrated in a real-life example, where an existing turbine SIS is modified to incorporate a new over-speed protection system. The simplified models and the turbine upgrade project are also used to explain the issue of unknowns and uncertainties in reliability analysis and how these issues can be addressed in SIS architecture by optimizing component arrangement. 相似文献
786.
787.
Yun Zhu Yanwen Lao Carey Jang Chen-Jen Lin Jia Xing Shuxiao Wang Joshua S. Fu Shuang Deng Junping Xie Shicheng Long 《环境科学学报(英文版)》2015
This article describes the development and implementations of a novel software platform that supports real-time, science-based policy making on air quality through a user-friendly interface. The software, RSM-VAT, uses a response surface modeling (RSM) methodology and serves as a visualization and analysis tool (VAT) for three-dimensional air quality data obtained by atmospheric models. The software features a number of powerful and intuitive data visualization functions for illustrating the complex nonlinear relationship between emission reductions and air quality benefits. The case study of contiguous U.S. demonstrates that the enhanced RSM-VAT is capable of reproducing the air quality model results with Normalized Mean Bias < 2% and assisting in air quality policy making in near real time. 相似文献
788.
789.
为推进农村环境综合整治工作,针对环办[2010]136号规定评估指标体系应用过程中遇到的问题,采取定义与计算、定性与定量结合的方法,对规定评估指标进行定义、明确赋分依据,确定不同完成程度下的赋分标准和计算方法,为环境成效评估提供科学、准确、可行、实用的赋分依据和办法。 相似文献
790.
煤矸石是我国排放量最大的工业固体废物之一,其长期存放,不仅占用大量土地,而且还会污染大气、土壤和水体。本文介绍了我国煤矸石综合利用技术政策和控制目标,分析了我国煤矸石综合利用现状,在此基础上展望煤矸石综合利用的发展前景。 相似文献