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991.
Nanotechnology is a broad and complex discipline that holds great promise for innovations that can benefit mankind. Yet, one must not overlook the wide array of factors involved in managing nanomaterial development, ranging from the technical specifications of the material to possible adverse effects in humans. Other opportunities to evaluate benefits and risks are inherent in environmental health and safety (EHS) issues related to nanotechnology. However, there is currently no structured approach for making justifiable and transparent decisions with explicit trade-offs between the many factors that need to be taken into account. While many possible decision-making approaches exist, we believe that multi-criteria decision analysis (MCDA) is a powerful and scientifically sound decision analytical framework for nanomaterial risk assessment and management. This paper combines state-of-the-art research in MCDA methods applicable to nanotechnology with a hypothetical case study for nanomaterial management. The example shows how MCDA application can balance societal benefits against unintended side effects and risks, and how it can also bring together multiple lines of evidence to estimate the likely toxicity and risk of nanomaterials given limited information on physical and chemical properties. The essential contribution of MCDA is to link this performance information with decision criteria and weightings elicited from scientists and managers, allowing visualization and quantification of the trade-offs involved in the decision-making process.  相似文献   
992.
本文通过理论分析及实验测试,研究燃气机热泵系统启动过程和大范围变容量调节过程中系统流量特性,提出了适合于燃气机热泵系统的电子膨胀阀流量控制策略.结果表明文中所提出的模糊自适应PID控制方法和模糊PID控制方法的控制性能要优于常规的PID控制方法.  相似文献   
993.
介绍了模板匹配和特征识别两种识别方案,采用数字图像处理技术和模式识别技术,实现了细胞显微图像中的细胞自动识别与分类.实验结果表明,特征识别具有直接性、运算量小等特点,为细胞显微图像的模式识别提供了可靠有效的方法.  相似文献   
994.
图像融合效果评价方法研究   总被引:2,自引:1,他引:2  
以IKONOS影像为数据源,对IHS、PC,Gram—Schmidt和基于亮度调节的平滑滤波(SFIM)四种融合算法进行融合处理,对其结果进行了评价.结果表明,定性比较主观性较强,定量比较方法虽多,但大都有一定的局限性,不同谱段的计算结果总有些差异.因此,定量评价时应该多选一些波段与评价方法才能获得比较客观的评价结果.光谱曲线的比较不失为一种比较好的方法,在对光谱曲线进行比较时本文引入了光谱角度和几何距离两种方法进行定量的比较.  相似文献   
995.
Objective image quality mcasure, which is a fundamental and challenging job in image processing, evaluates the image quality consistently with human perception automatically. On the assumption that any image distortion could be modeled as the difference between the directional projection-based maps of reference and distortion images, wc propose a new objective quality assessment method based on directional projection for full reference model. Experimental results show that the proposed metrics are well consistent with the subjective quality score.  相似文献   
996.
To solve a mathematical model for American put option with uncertainty, we utilize two essentials, i.e., a λ-weighting function and a mean value of fuzzy random variables simultaneously. Estimation of randomness and fuzziness as uncertainty should be important when we deal with a reasonable and natural model extended from the original optimization/decision making. Three kinds of mean values by fuzzy measures, which are based on Possibility, Necessity and Credibility, are demonstrated particularly. We consider the optimal expected price of the American put option by dynamic programming under a reasonable assumption. A numerical example is given to illustrate our idea.  相似文献   
997.
In this study we first present the preference structures in decision making as a generalized non-linear function. Then, we incorporate it into a fuzzy linear inequality of which the progressive and conservative manners are described by the concept of target hyperplanes. Thus, ones preference domain is said to be bounded by such soft constraint. When facing different situations, a membership function is defined as an evaluation function for incorporating ones optimistic or pessimistic attitude into this soft constraint. Once a goal is pursued, the problem is transformed into a symmetric fuzzy linear program. Based on max–min principle, an auxiliary crisp model in the form of a generalized fractional program is derived. Then, Dinkelbach-type-2 and the bisection algorithms are adopted for solution. Finally their simulation results of an uncertain production scheduling problem are reported.  相似文献   
998.
In this paper, we study some of properties of the min-max compositions of fuzzy matrices and give out a dual theorem (to Theorem 3 of [4]) about the convergence of the power sequence of min-max compositions of fuzzy matrices.AMS Subject Classification (2000) 15A45 06A06 04A72  相似文献   
999.
本讨论二阶微分方程的第二边值问题具有模糊不确定性时,运用模糊仿真原理和差分方法,求其边值问题的数值解法。  相似文献   
1000.
模糊层次分析法及在军校学员综合素质评估中的应用   总被引:3,自引:0,他引:3  
通过定义模糊数的限位系数 ,得到由限位系数确定模糊数排序的新方法 ,并将其运用于层次分析排序 ,改进了层次分析法的理论及方法 .最后介绍了模糊层次分析法在军校学员综合素质评估体系中的应用实例 .  相似文献   
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