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《化学工业与工程技术》2022,(1):30-37
人工神经元网络(ANN)是一种通过模拟大脑处理信息的方式发展起来的数据处理技术,在石油和天然气领域中被广泛用于产量预测、甲烷物性计算、甲烷吸附与分离以及甲烷催化转化等领域。针对甲烷催化转化领域,综述了近年来ANN技术在甲烷干重整、蒸汽重整、联合重整和氧化偶联反应中的应用进展,结果表明:ANN在预测甲烷转化率、产物收率等方面具有准确性好、泛化能力强、鲁棒性好的优点,在催化工艺优化、催化剂组成优化等方面也有很好的应用,对该领域存在的问题以及未来的研究方向进行了总结和展望。 相似文献
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大部分复杂的塑料制品均采用注射成型生产。注塑制品质量的预测和制品质量的优化是注射成型过程中的重要步骤。人工神经网络(ANN)作为人工智能最常用的方法已经被应用到注射成型中,但是,仍存在训练成本较高、构建模型复杂等缺陷。ANN预测模型可以拟合注塑过程,并且,优化注塑制品质量。以工艺参数和过程参数作为输入数据的ANN预测模型不仅可以预测注塑制品质量,还可以结合智能优化算法优化注塑工艺参数。并且,对减少ANN预测模型训练成本的方法进行了综述。最后,总结了ANN预测模型在注塑制品优化中的进展和发展方向。 相似文献
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Drying rate data were generated for training of an ANN model using a liquid diffusion model for potato slices of different thicknesses using air at different velocities, humidities and temperatures. Moisture content and temperature dependence of the liquid diffusivity as well as the heat of wetting for bound moisture were included in the diffusion model making it a highly nonlinear system. An ANN model was developed for rapid prediction of the drying rates using the Page equation fitted to the drying rate curves. The ANN model is verified to provide accurate interpolation of the drying rates and times within the ranges of parameters investigated. 相似文献
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《Drying Technology》2013,31(9):1867-1884
Abstract Drying rate data were generated for training of an ANN model using a liquid diffusion model for potato slices of different thicknesses using air at different velocities, humidities and temperatures. Moisture content and temperature dependence of the liquid diffusivity as well as the heat of wetting for bound moisture were included in the diffusion model making it a highly nonlinear system. An ANN model was developed for rapid prediction of the drying rates using the Page equation fitted to the drying rate curves. The ANN model is verified to provide accurate interpolation of the drying rates and times within the ranges of parameters investigated. 相似文献
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Sayyed Mahdi Hejazi Sayyed Mahdi Abtahi Mohammad Sheikhzadeh Dariush Semnani 《应用聚合物科学杂志》2008,109(5):2872-2881
Scientists and engineers are constantly trying to improve the performance of asphalt pavements. Modification of the asphalt binder is one approach taken to improve pavement performance. The idea of using fibers to improve the behavior of materials is an old suggestion, so different researchers reported the results of adding a large variety of fibers to asphalt concrete (AC) as fiber‐reinforced asphalt concrete (FRAC). However, there are few comments about the mechanism of reinforcement and fiber performance in the inner structure of AC and/or exposing some models to predict fiber recital as a modifier in FRAC. So this article is going to introduce two simple models for predicting FRAC behavior during longitudinal loads. The former is called “Slippage Theory” and the latter is “Equal Cross‐Section.” Finally, four types of fibers (glass, nylon 6.6, polypropylene, and polyester) were used in AC to evaluate the two theories. “Marshall Test,” as stability and flow outcomes, and “Specific Gravity” were carried out on specimens in the next stages followed by an artificial neural network (ANN), which was developed in the system to recognize important fiber parameters effective in the FRAC specifications. In the end, the two theories predicted each fiber performance in FRAC as well as ANN. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
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Mayke Werner Niels Rothermel Hergen Breitzke Torsten Gutmann Gerd Buntkowsky 《Israel journal of chemistry》2014,54(1-2):60-73
In the past years, porous media have become a major focus of materials science, due to their versatile properties, such as high surface area, low specific weight, high surface functionality, and the ability to customize their surface properties. Applications of porous media range from catalysis to separation media to gas storage. All of the mentioned applications involve the introduction of guest molecules into the pores. For efficient application of the materials, it is essential to know the behavior of these introduced molecules in the confined state. Solid state (ss) NMR gives a unique insight into the dynamics, the guest-host interactions, and the binding sites of porous materials and is probably the most powerful characterization method for probing a huge variety of real-life systems. Recent results in research of microporous zeolites and periodically mesoporous silica (PMS) materials using NMR will be highlighted. 相似文献
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Thiago Gonçalves das Neves Wagner Brandão Ramos Gilvan Wanderley de Farias Neto Romildo Pereira Brito 《Korean Journal of Chemical Engineering》2018,35(4):826-834
We developed and implemented an intelligent control system to be used in an extractive distillation column that produces anhydrous ethanol using ethylene glycol as solvent. The concept of artificial neural networks (ANN) was used to predict new setpoints after disturbances, and proved to be a fast and feasible solution. The developed control system receives data from temperature, flowrate and composition measurements of the azeotrope feed, and the ANN estimates the new set-points of the controllers to maintain 99.5 mol% of ethanol at the top and less than 0.1mol% at the bottom; feed composition was also estimated using an ANN. All ANN were trained to provide output data corresponding to an optimized operating condition. The results showed that the intelligent control system can predict a new operating condition for any disturbance in the column feed and presented superior performance when compared with the control system without ANN. 相似文献
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Istvan Hargittai 《Israel journal of chemistry》2011,51(11-12):1144-1152
Dan Shechtman’s discovery of quasicrystals brought about a paradigm change in chemistry, physics, materials science, and other areas of science and engineering. Although superficially it could be looked at as a serendipitous event, Shechtman’s curiosity and drive played equal parts with serendipity in this discovery. Shechtman was a lonely discoverer, again, seemingly detached from the main stream of generalized crystallography for which his contribution was a milestone. Generalized crystallography is the science of structures without restrictions — “structures beyond crystals.” 1 The discovery of quasicrystals can be seen as written into the history of ideas that have much extended our views about the tools of our scientific inquiry and the materials we aim at producing and utilizing. This review augments a recent Editorial in the August 2011 issue of Structural Chemistry about the lessons of the quasicrystal discovery 2 and a book chapter about Dan Shechtman’s traits as a discoverer and about his road to the discovery. 3 相似文献
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由于催化裂化系统的变量众多,每个故障的发生都可能涉及众多操作变量,这给故障的准确判断带来困难.人工神经网具有很强的自适应能力,非线性映射能力和泛化能力也很强,对数据进行高度并行处理,可自然处理多输入信号.用于催化裂化的故障诊断,取得较好的效果.将改进的LM算法用于人工神经网的训练,提高了网络的收敛速度. 相似文献
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发酵过程生物量软测量技术的研究进展 总被引:4,自引:0,他引:4
生物量是发酵过程中的关键过程参数之一,它直接影响着发酵过程的优化和控制。综述了近年来发酵过程生物量软测量技术的研究现状,讨论了基于过程机理分析、回归分析、状态估计和神经网络等的软测量建模方法,对基于神经网络和改进的神经网络建模方法进行了分析。指出基于多尺度建立软测量混合模型,是实现发酵过程生物量在线测量的有效方法,并给出了建立混合模型需要解决的关键问题。 相似文献
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Hong Jiang Yiyong Tan Junfeng Lei Libo Zeng Zelan Zhang Jiming Hu 《Journal of Automated Methods and Management in Chemistry》2003,25(4):87-92
The current method to classify graphite morphology types of grey cast iron is based on traditional subjective observation, and it cannot be used for quantitative analysis. Since microstructures have a great effect on the mechanical properties of grey cast iron and different types have totally different characters, six types of grey cast iron are discussed and an image-processing software subsystem that performs the classification and quantitative analysis automatically based on a kind of composed feature vector and artificial neural network (ANN) is described. There are three kinds of texture features: fractal dimension, roughness and two-dimension autoregression, which are used as an extracted feature input vector of ANN classifier. Compared with using only one, the checkout correct precision increased greatly. On the other hand, to achieve the quantitative analysis and show the different types clearly, the region segmentation idea was applied to the system. The percentages of the regions with different type are reported correctly. Furthermore, this paper tentatively introduces a new empirical method to decide the number of ANN hidden nodes, which are usually considered as a difficulty in ANN structure decision. It was found that the optimum hidden node number of the experimental data was the same as that obtained using the new method. 相似文献