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21.
Shilong Ma 《Computers & Industrial Engineering》1995,29(1-4):187-191
This paper presents an interactive framework for constructing models from high-level specifications of real physical systems, deriving low-level simulations from the constructed models and then generating explanations of the simulated behavior to help engineers interpret and control the real physical systems. To demonstrate our method, we show an example of modeling river networks, which are eco-environmental engineering systems, to provide a computer-based solution to problems of simulating and controlling concentrations of water quality constituents in river networks[1]. 相似文献
22.
铁在盐酸中的缓蚀剂的两种作用类型的研究 总被引:6,自引:0,他引:6
通过腐蚀电位、极化曲线与交流阻抗测量研究了3种伯胺和丙炔醇对铁在盐酸中的缓蚀作用类型。结果表明,3种伯胺的缓蚀作用是几何覆盖效应,而丙炔醇的缓蚀作用则来自负催化效应。还证明,在强阳极极化的Tafel 直线区间,十二烷胺吸附在电极表面的覆盖率θ不随电位改变,十四烷胺的θ随电位的升高而增大。丙炔醇使铁阳极溶解反应活化能位垒增高的量.fa(θ)随电位升高而减小,其数值为df_a(θ)/dE=-73J·mol_-1.mV-1。 相似文献
23.
24.
聚苯胺盐的合成及导电性能研究 总被引:3,自引:0,他引:3
用对甲苯磺酸作为掺杂剂对聚苯胺(PANI)进行掺杂,合成了导电聚苯胺盐(ES)。研究了掺杂剂用量、模压压力、模压温度、氧化剂用量对聚苯胺盐电导率的影响。结果表明:随着掺杂剂用量的增加,PANI的电导率也在不断的增大;当ES所受压力较高时,电导率提高;高温使PANI电导率上升;氧化剂与苯胺的最佳配比为1:1。 相似文献
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26.
《Expert systems with applications》2014,41(7):3223-3236
Clustering is the process of organizing objects into groups whose members are similar in some way. Most of the clustering methods involve numeric data only. However, this representation may not be adequate to model complex information which may be: histogram, distributions, intervals. To deal with these types of data, Symbolic Data Analysis (SDA) was developed. In multivariate data analysis, it is common some variables be more or less relevant than others and less relevant variables can mask the cluster structure. This work proposes a clustering method based on fuzzy approach that produces weighted multivariate memberships for interval-valued data. These memberships can change at each iteration of the algorithm and they are different from one variable to another and from one cluster to another. Furthermore, there is a different relevance weight associated to each variable that may also be different from one cluster to another. The advantage of this method is that it is robust to ambiguous cluster membership assignment since weights represent how important the different variables are to the clusters. Experiments are performed with synthetic data sets to compare the performance of the proposed method against other methods already established by the clustering literature. Also, an application with interval-valued scientific production data is presented in this work. Clustering quality results have shown that the proposed method offers higher accuracy when variables have different variabilities. 相似文献
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29.
Y. B. Che Man L. S. Wei A. I. Nelson N. Yamashita 《Journal of the American Oil Chemists' Society》1991,68(7):471-473
Soaking soybeans in dilute acids affected activities of lipoxygenase, trypsin inhibitor and urease. Effects of soaking time,
acid concentration and soaking temperature were investigated. Lipoxygenase activity was completely eliminated by soaking in
0.3 M HC1 at either 23°C or 40°C for 8 hr. Less than 50% trypsin inhibitor remained and urease was inactivated to an acceptable
level (0.04 ΔpH). 相似文献
30.
Nasirullah K. N. Ankaiah M. N. Krishnamurthy K. V. Nagaraja 《Journal of the American Oil Chemists' Society》1991,68(6):446-447
Two edible oil blends, namely groundnut oil:rice-bran oil and mustard oil:rice-bran oil, were prepared in different proportions
and stored for a period of three years. Their physicochemical characteristics were determined. The results agreed with expected
values except for free fatty acid percents and butyrorefrac-tometer readings, presumably due to rancidity. Fatty acid compositions
of the blends were determined and ratios of characteristic fatty acids, like lignoceric to palmitic for groundnut oil:rice-bran
oil blends, and erucic to palmitic for mustard oil:rice-bran oil blends, were calculated to identify individual oils in the
blend. 相似文献