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301.
改进的RSA方法在参数全局灵敏度分析中的应用 总被引:1,自引:0,他引:1
灵敏度分析是模型参数识别的重要方法. 参照一维情形,采用统计分布特征值,对传统意义上的参数灵敏度分析进行了扩展,将参数灵敏度定义从一维扩展到多维,为在多维情形下分析参数的灵敏度提供思路. RSA方法是全局灵敏度分析的重要方法,但其对参数的二元划分具有一定的局限性,因此对其进行一定的改进:①将RSA方法对参数集的二元划分扩展为多元划分.②分析对象不局限于对模型参数值的分布,也包括模型目标函数的分布,即研究在函数各取值区间,参数的分布是否具有明显的变化;研究在参数各取值区间,函数的响应是否具有明显的变化. 以n2的Rosenbrock函数作测试函数,对改进的RSA方法进行了检验. 以模型参数为基础的分析结果和以模型目标函数为基础的分析结果均表明,模型的2个参数的全局灵敏度都非常高,二者的分析结论一致. 相似文献
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Managing Aquatic Species of Conservation Concern in the Face of Climate Change and Invasive Species 总被引:2,自引:0,他引:2
Abstract: The difficult task of managing species of conservation concern is likely to become even more challenging due to the interaction of climate change and invasive species. In addition to direct effects on habitat quality, climate change will foster the expansion of invasive species into new areas and magnify the effects of invasive species already present by altering competitive dominance, increasing predation rates, and enhancing the virulence of diseases. In some cases parapatric species may expand into new habitats and have detrimental effects that are similar to those of invading non-native species. The traditional strategy of isolating imperiled species in reserves may not be adequate if habitat conditions change beyond historic ranges or in ways that favor invasive species. The consequences of climate change will require a more active management paradigm that includes implementing habitat improvements that reduce the effects of climate change and creating migration barriers that prevent an influx of invasive species. Other management actions that should be considered include providing dispersal corridors that allow species to track environmental changes, translocating species to newly suitable habitats where migration is not possible, and developing action plans for the early detection and eradication of new invasive species. 相似文献
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尿素添加剂湿法烟气同时脱硫脱氮工艺实验研究(Ⅱ) 总被引:2,自引:0,他引:2
对EA和PA两种添加剂,工艺条件变化对NOx脱除率影响有相同的规律:NOx脱除率不受烟气的浓度变化影响;随烟气的氧化度和吸收反应塔有效高度的增加而迅速增加。对吸收反应温度、尿素和添加剂质量分数、吸收塔有效高度进行正交实验得出最佳工艺条件为:吸收反应温度70℃;吸收塔有效高度1.8m;尿素和添加剂质量分数分别为10%和0.01%。在最佳工艺条件作验证实验得出结果与正交实验得出的结果基本符合,此时SO2脱除率为100%,NOx脱除率大于75%。 相似文献
307.
活性污泥法处理味精厂废水的工艺优化 总被引:1,自引:0,他引:1
经过总结与改进武汉味全食品有限公司近 5年污水处理工艺、设备 ,结果表明 ,经过增加三级曝气池、罗茨鼓风机等工艺改进 ,SS由 132mg/L降为 112mg/L ;NH3 N由 119mg/L降为 37 6mg/L ;Ar OH由 0 0 1mg/L降为 0 0 0 9mg/L ;BOD5由 5年前的 34 6mg/L降为现在的 2 1 2mg/L ;COD由 5年前的 117mg/L降为现在的 6 2 6mg/L ;运行成本由 85 0万降到 4 5 0万 ,通过此工艺的改进及优化 ,基本达到国家污水排放标准 ,完全达到行业排放标准 相似文献
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OCI Nitrogen wants to gain knowledge of (leading) indicators regarding the process safety performance of their ammonia production process. This paper answers the question whether indicators can be derived from the barrier system status to provide information about the development and likelihood of the major accident processes in the ammonia production process.The accident processes are visualized as scenarios in bowties. This research focuses on the status of the preventive barriers on the left-hand side of the bowtie. Both the quality – expressed in reliability/availability and effectiveness – and the activation of the barrier system give an indication of the development of the accident scenarios and the likelihood of the central event. This likelihood is calculated as a loss of risk reduction compared to the original design. The calculation results in an indicator called “preventive barrier indicator”, which should initiate further action. Based on an example, it is demonstrated which actions should be taken and what their urgency is. 相似文献
309.
Accidents involving contractors continue to occur with regular frequency. By using the standard set within the PSM 29 CFR 1910.119(h) regulations, it has been identified that certain aspects of the way contractors do work are not up to the stipulated regulatory requirements especially regarding matters like not providing mandatory personal protective equipment (PPE) to the workers, not discussing hazards related to handling procedures with the workforce and improper control of non-routine activities during changes in shifts. The PSM 29 CFR 1910.119(h) regulations promulgated in 1992 provides standards that covered processes to obtain and evaluate data regarding contractors' health and safety programs as well as the contractors' performance evaluation. Many of the accidents involving contractors are direct result of poor training of contractors and/or poor control of the contracted work. Even though most organizations have their own contractor management systems, there are issues in meeting the requirements of PSM. The PSM standard only state “what to do” not “how to do it”. This is known as self-regulatory policy which depends on the industries understanding to interpret the standard that also contribute to this problem. This paper presents a structured and easy technique to plan and implement a practical and comprehensive contractors' management system in process industries that will comply with OSHA CFR 1910.119. A model has been developed based on this technique and its application has been tested in a pilot plant for compliance to PSM regulation. The model is beneficial to the process industries as any deficiencies in the PSM contractors' management program will be highlighted by the model which will then easily correct the identified deficiency so as to minimize and prevent catastrophic accidents. 相似文献
310.
Risk Communication is increasingly important to the chemical and manufacturing industries in the wake of a wave of major incidents in recent years. However, risk communication strategies as they are currently implemented tend to place the chemical industry on the defensive. Renewed attempts should be made to place the life-saving benefits of the chemical industry back in the public eye and counter-balance the popular political view that the chemical industry is often responsible for loss of life. In truth, while the chemical industry suffers on the job fatalities like many industries, the frequency is much less than many common industries and the chemical industry provides benefits to society that ultimately save far more lives. 相似文献