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341.
组织管理因素与煤矿安全生产密切相关。该文从人的管理、组织机构管理、企业环境管理、现场及技术管理四个方面详细分析了煤矿组织管理中的主要影响因素,提出一种基于核校准和支持向量机(SVM)的组织管理安全评价等级预测方法,构建了影响因素形成的输入空间到评价等级空间的非线性映射,并详尽分析了组织管理的安全评价等级与各影响因素的关联关系。在此基础上,本文深入研究煤矿安全中各组织管理因素的作用规律,并探讨了相应的预防措施与控制方法。实例分析结果表明,该方法能够合理地反映煤矿企业的组织管理安全评价状况,有助于煤矿企业采取相应措施预防或减少安全事故的发生,同时,也为企业提高本质安全管理水平提供了参考,有较强的实用性。 相似文献
342.
Abstract: Conservation of wildlife is especially challenging when the targeted species damage crops or livestock, attack humans, or take fish or game. Affected communities may retaliate and destroy wildlife or their habitats. We summarize recommendations from the literature for 13 distinct types of interventions to mitigate these human–wildlife conflicts. We classified eight types as direct (reducing the severity or frequency of encounters with wildlife) and five as indirect (raising human tolerance for encounters with wildlife) interventions. We analyzed general cause‐and‐effect relationships underlying human–wildlife conflicts to clarify the focal point of intervention for each type. To organize the recommendations on interventions we used three standard criteria for feasibility: cost‐effective design, wildlife specificity and selectivity, and sociopolitical acceptability. The literature review and the feasibility criteria were integrated as decision support tools in three multistakeholder workshops. The workshops validated and refined our criteria and helped the participants select interventions. Our approach to planning interventions is systematic, uses standard criteria, and optimizes the participation of experts, policy makers, and affected communities. We argue that conservation action generally will be more effective if the relative merits of alternative interventions are evaluated in an explicit, systematic, and participatory manner. 相似文献
343.
Abstract Based on the formation process of the Loess Plateau, the characteristics comparison between loess and ancient soil and the located materials of spore- pollen, ancient stone artifact, history, geography and soil erosion, the analysis reveals that the present state serious soil erosion in Loess Plateau, instead of being a natural geologic course, is a consequence of destruction of vegetation, irrational land utilization and the direct destruction of soil permeability and anti-erosion ability, esp. anti-scourability. The water and soil conservation measures, with the twenty-eight-word amelioration principle as the core, are the basis for exploiting and improving water and soil resources of the Loess Plateau so as to harness the Huanghe (the Yellow River). 相似文献
344.
湿天然气集输管道系统运行时间长,管道腐蚀严重,失效泄漏事故频发,其系统风险评价面临诸多问题,因而研究其腐蚀率预测有重要意义。基于灰色支持向量机(GSVM)方法,综合考虑管道材质及其各种影响因素,对其进行灰色相关分析,并根据结果选取有较高相关度的影响因子作为输入变量,将腐蚀率作为目标输出函数,建立湿天然气集输管道腐蚀预测模型。并通过实证分析比较,发现用该模型计算出的管道腐蚀率平均相对误差较小,其预测结果与实际值吻合程度较高,使预测精度得到提高。 相似文献
345.
Perceived organizational support (POS) theory specifies three mechanisms—felt obligation, group identification, and outcome expectancy—to explain the effects of organizational support on employee work outcomes. These mechanisms have usually been examined in isolation so that it is not possible to assess their relative explanatory power. The present study aims to remedy this problem by examining the three mechanisms simultaneously using structural equation modeling. On the basis of a sample of 206 bank employees in China, we focus on two types of employee performance—task performance and creativity—as dependent variables. Drawing on self‐determination theory and characteristics of the research context, we propose that task performance is more strongly predicted by felt obligation than by the other two mechanisms, whereas identification and expectancy more strongly predict creativity than felt obligation. We conclude by discussing our contribution to POS and creativity research, and highlight some important implications of our findings. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
346.
Applications of Total Maximum Daily Load (TMDL) criteria for complex estuarine systems like Chesapeake Bay have been limited by difficulties in estimating precisely how changes in input loads will impact ambient water quality. A method to deal with this limitation combines the strengths of the Chesapeake Bay's Water Quality Sediment Transport Model (WQSTM), which simulates load response, and the Chesapeake Bay Program's robust historical monitoring dataset. The method uses linear regression to apply simulated relative load responses to historical observations of water quality at a given location and time. Steps to optimize the application of regression analysis were to: (1) determine the best temporal and spatial scale for applying the WQSTM scenarios, (2) determine whether the WQSTM method remained valid with significant perturbation from calibration conditions, and (3) evaluate the need for log transformation of both dissolved oxygen (DO) and chlorophyll a (CHL) datasets. The final method used simple linear regression at the single month, single WQSTM grid cell scale to quantify changes in DO and CHL resulting from simulated load reduction scenarios. The resulting linear equations were applied to historical monitoring data to produce a set of “scenario‐modified” DO or CHL concentration estimates. The utility of the regression method was validated by its ability to estimate progressively increasing attainment in support of the 2010 Chesapeake Bay TMDL. 相似文献
347.
William R. Michaud 《Journal of the American Water Resources Association》2013,49(3):693-699
Does collaborative modeling improve water resource management outcomes? How does collaborative modeling improve these outcomes? Does it always work? Under what conditions is collaborative modeling most appropriate? With support from the U.S. Army Corps of Engineers' Institute for Water Resources (IWR), researchers developed an evaluation framework to help address these questions. The framework links the effects of collaborative modeling on decision‐making processes with improvements in the extent to which resource management decisions, practices, and policies balance societal needs. Both practitioners' and participants' experiences suggest that under the right circumstances, collaborative modeling can generate these beneficial outcomes. Researchers developed performance measures and a survey to systematically capture these experiences and evaluate the outcomes of collaborative modeling processes. The survey can provide immediate feedback during a project to determine whether collaborative modeling is having the desired effect and whether course correction is warranted. Over the longer term, the systematic evaluation of collaborative modeling processes will help demonstrate in what ways and under what circumstances collaborative modeling is effective, inform and improve best practices, and raise awareness among water resource planners regarding the use of collaborative modeling for resource management decisions. 相似文献
348.
A. Michael S. Sheer Michael W. Nemeth Daniel P. Sheer Megan Van Ham Michael Kelly David Hill Samuel D. Lebherz 《Journal of the American Water Resources Association》2013,49(3):654-668
The Bow River Basin is a cornerstone of Alberta's development. In 2010, stakeholders representing interests from agriculture, municipalities, environment, and more formed the Bow River Project Research Consortium to help determine the potential for improving the operations in the basin. At present, upstream reservoirs are operated primarily for hydropower, whereas downstream reservoirs are operated for irrigation. Through Collaborative Modeling for Decision Support the stakeholders were able to develop a new method for operating the system that would dramatically improve environmental performance. The main components of the new operating strategy called for: purchase or setting aside of a small amount of storage volume in the power reservoirs; a set of rules for releases from that storage; an agreement by the major irrigation districts with the largest water licenses to utilize their ability to shift deliveries to and from their large offstream storage reservoirs to allow for increased instream flows, and to allow junior water license holders (mainly municipal and industrial supplies) an uninterrupted water supply; limitations of reservoir fluctuations to improve inreservoir habitat for fisheries; and increased minimum flows throughout the system leading to improved environmental outcomes. Costs of this strategy were minimal, impacts on power revenue were estimated at <US$2 million/yr on average. Compensatory arrangements should be possible. 相似文献
349.
350.
M. Karamouz B. Zahraie Sh. Araghi‐Nejhad M. Shahsavari S. Torabi 《Journal of the American Water Resources Association》2001,37(5):1301-1311
ABSTRACT: In this paper, a system approach to water resources development in Tehran Metropolitan Area, with its complex system of water supply and demands, is discussed. Water resources in this region include water storage in the Lar, Latyan, and Karaj reservoirs, the Tehran aquifer, as well as water discharge in local rivers and in drainage channels (mainly supplied by urban runoff and wastewater). This study consists of three phases of long‐term water resources planning and management in the Tehran metropolitan area. In each phase, a different level of details among different components of the system is considered. In the first phase, optimal operating policies for Tehran reservoirs and a decision support system are developed. In the second phase, interactions between surface and ground water resources as well as surface runoffs and wastewater disposal in different subareas are investigated. The water table fluctuations as a result of implementing sewerage collection project was also simulated. In the last phase, long‐term scenarios for water resources and agricultural development in the Southern part of Tehran are defined, and the effects of each scenario on the quality and quantity of surface and ground water resources are studied. 相似文献