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961.
A method for the screening of multiple attribute decision-making problems is presented. The model assists the decision-maker in eliminating inferior alternatives and insignificant attributes prior to a detailed evaluation. A preliminary evaluation of the alternatives provides the information necessary for the reduction of the decision problem. The procedure calculates maximum preference factors on which the decision-maker can base his screening decisions. These factors assess the role of alternatives in the final ranking by estimating their potential to become superior to other alternatives. Since screening tasks are carried out early in decision-making, the information available is generally uncertain. Uncertainty is represented in the model using fuzzy sets. This framework permits the handling of both imprecise and precise (crisp) estimates of impacts and provides a possibil-istic assessment of the risk associated with screening decisions. 相似文献
962.
963.
P. Ebrahimi S. M. Razavi S. Ismaeili M. Azarpour 《Petroleum Science and Technology》2013,31(11):1188-1195
Recognition of hydrocarbon migration is so vital for petroleum exploration. Developing intelligent systems (artificial neural network) enable experts to achieve more details from seismic data. Although detection of migration direction using seismic data is difficult, Chimney-cube analysis overcomes this problem. The authors used several filters, seismic attributes, neural network (supervised and unsupervised), and interpreters' viewpoints. In supervised method artificial and human intelligence cover their limitations and in unsupervised method the authors eliminate the experts' views. Chimney recognizes the migration direction and locates the spill points, mud volcanoes, gas seepages, sealing, and nonsealing faults and finally the origin of hydrocarbon. 相似文献
964.
Eric Biehler Frédéric Mayer Lucien Hoffmann Elmar Krause Torsten Bohn 《Journal of food science》2010,75(1):C55-C61
ABSTRACT: Carotenoids are C-40 tetraterpenoid compounds with potential health beneficial effects. Major dietary sources include a variety of fruits and vegetables. Rapid screening methods are therefore desired, but their accuracy varies depending on the carotenoid profile and the matrix of the plant food. In the present study, 3 different methods were compared, all based on a rapid extraction protocol and spectrophotometric measurements to determine the total amount carotenoids present in fruits and vegetables (n = 28), either with or without chlorophyll. Published methods (a) Lichtenthaler and (b) Hornero-Méndez and Mínguez-Mosquera were compared with a newly developed method (method c) based on the average molar absorption coefficient (135310 Lcm−1mol−1) and wavelength (450 nm in acetone), for the 5 predominant carotenoid species (beta-carotene, zeaxanthin, lycopene, lutein, beta-cryptoxanthin) in the investigated foods. All results were compared to HPLC (method d). To avoid overestimating carotenoid concentrations due to chlorophyll A and B presence, the effect of saponification was studied for all methods. Overall, saponification led to significant carotenoid losses (12.6 ± 0.9%). Methods a, b, c, and d yielded 5.1 ± 0.4 mg/100 g, 4.6 ± 0.5 mg/100 g, 4.3 ± 0.5 mg/100 g, and 4.2 ± 0.5 mg/100 g total carotenoids, respectively, with method a leading to significant higher mean concentrations compared to all other methods (P < 0.001, Bonferroni) with methods b and c being not significantly different and highly correlated compared to HPLC (> r = 0.95). Similar results were found when stratifying for chlorophyll content and fruits compared with vegetables, however, accuracy varied for individual fruits, highlighting the limitation to use the same method for all plant foods. Practical Application: This study presents a comparison of various rapid spectrophotometric measurements to determine total carotenoid content in various fruits and vegetables and could aid in the selection of the appropriate method for individual plant foods with different carotenoid profile and matrices. 相似文献
965.
Prediction of overall glucose yield in hydrolysis of pretreated sugarcane bagasse using a single artificial neural network: good insight for process development 下载免费PDF全文
966.
967.
人工物设计的安全研究 总被引:2,自引:2,他引:0
从人的生物特征和生理意识分析了人工物中安全因素的内涵,从人类心理的角度剖析了设计师与使用者不同的概念模式及其成因,并从技术哲学的角度探析了人工物与人类安全的辩证关系,最后提出现代人工物安全设计的发展方向和原则. 相似文献
968.
969.
将有限元法同人工透射边界的处理方法结合起来,首次以一种图象清楚、过程简单、适应性强的计算方法对目标散射问题进行讨论,对简单散射问题与解析解对比,并讨论误差情况. 相似文献
970.
盐酸直接浸取钛铁矿制取人造金红石 总被引:1,自引:0,他引:1
研究了盐酸直接浸取钛铁矿制取金红石的方法,探讨了搅拌条件、盐酸浓度、浸取时间、温度、矿粉粒度对浸取效果的影响,利用X-粉末衍射证明所得产物实现了由锐钛型至金红石型的转型,得到了浸取过程的最佳工艺条件为盐酸浓度6.27mol/L;浸取温度110℃;液固比4:1(质量);颗粒粒径300目以下 相似文献