جستجوی مقالات مرتبط با کلیدواژه "artificial neural networks" در نشریات گروه "مهندسی شیمی، نفت و پلیمر"

Lozenge rug chaleshtor is in terms of artistic and aesthetic aspects, it is considered one of the consumer and capital goods that have international fame. From the past until now, this native art has been traditionally produced with the same design, pattern, and colour without paying attention to the tastes of its audience, which can be one of the reasons for the failure of this original art in the global rug markets shortly. Therefore, knowledge and awareness of consumers' taste, which is considered as one of the steps before production, and using modern science, can help to produce according to the taste of the audience and, accordingly, to be more successful in terms of sales and providing high export statistics. To achieve this, in this article, sub-branches of artificial intelligence were used to achieve the taste of Lozenge rug chaleshtor audiences. Three algorithms more related to the subject, 1. artificial neural networks, 2. decision tree learning and 3. support vector machine are compared and finally, the most suitable algorithm for this subject is the artificial neural networkss for receiving the taste of the audience of the Lozenge rug chaleshtor and providing suitable patterns in the field of design. , role, colour, dimensions, texture and price according to the audience's taste, and it was tried to answer the question of whether that artificial neural networkss can introduce the principles of the audience's taste of lozenge rug chaleshtor. in structural fields. For this purpose, primary data in the field of design and role, colour, raw materials, texture, dyeing, dimensions and price were collected through the contact questionnaire and then, using an artificial neural networkss, an algorithm was designed, the results showed that traditional lozenge designs with half motifs curved and quiet, with bright, limited, soft colours, natural dyeing, dimensions under 6 meters and preferably square with a price per meter of up to 10 million tomans is the final taste of the audience of this type of rugs.Keywords: Taste,Lozenge Rug, Chaleshtor, Artificial Neural Networks

Osmotic dehydration of fig fruits (cv. Sabz) in ternary solution of water, sucrose and sodium chloride at different solution concentrations, temperature and process durations were analyzed. A comparative approach was made between artificial neural network (ANN) and response surface methodology (RSM) to predict the mass transfer parameters. Results showed that all independent variables positively decreased the weight meaning that increasing each factor resulted in increasing weight loss and this relationship was linear. Osmo-dehydrated figs had better quality compared to samples without osmosis. All four independent variables explained 94% of the weight loss, 90% moisture content reduction and 89% of the solid gain. The determined optimum processing conditions were temperature of 60°C, sucrose concentration of 70%, sodium chloride concentration of 5% and immersion time of 5h. The results showed that properly trained ANN model is found to be more accurate in prediction as compared to RSM model.

Expandable Poly Styrene (EPS) has many applications. This polymer prepared by the radical polymerization. This material has many uses in packaging and insulation industries Some of the properties of this polymer like low mechanical strength caused its applications to be limited. By adding some materials, these properties can be improved. Styrene Butadiene Styrene (SBS) is from the materials that which by adding it to the EPS it can improve its quality.

In this research, EPS having different percentages of SBS (0, 0.01, 0.02, 0.03) in different conversion percentages (0.6, 0.63, 0.66, 0.69) has been prepared. Different tests like Impact Test, Modular Melt Flow test, Vicat Softening Temperature test, Tensile at Break test, K-value test, Rochwell Hardness test and Elongation at Break test are done on the prepared polymer. Laboratory gained data has been simulated by Multi-Layer Perceptron (MLP) method of artificial neural networks (ANN) and the simulated data covers the laboratory data perfectly.

Investigating the tests show that in constant percentages of SBS in EPS with increase in conversion percentage of EPS, the numerical amount of the tests increases except MFI test (low MFI number means better quality). Increase in SBS percentage in the EPS, increases the properties of polymer. In addition, the results of simulation show that the laboratory data covers the the simulated data perfectly. The data obtained from the results of this reasearch can be used for predicting the data for the points which has not been tested. Adding SBS in different weight percentages of poly styrene in different conversion percentages in order to increase the properties of poly styrene has been used for the first time in this research and the laboratory data results in points which has not been tested has been acquired by applications of ANN.

Dispersed water-in-oil as a stable emulsion causes numerous problems in extraction, transportation and refining of the crude oil. In the most desalting units, high voltage electrical field is utilized to separate water and ionic components from the crude oil. The efficiency of desalting units depends on operational conditions and hence in this study the result of several parameters on salt content of output crude oil in a desalting unit was considered for both theoretical and experimental studies. For this goal, optimized artificial neural network (ANN) using cuckoo optimization algorithm was applied to simulate the process. The optimum temperature, water  injection rate, retention time, differential pressure of mixing valves and injection rate of demulsifier were predicted by the consequences of simulation as the optimum value for each of the parameters was respectively equal to 79 ppm, 3.25%, 8.5 bar and 90 ppm. Then, because of the significant effect of the demulsifiers, the variation of each parameter was evaluated in the presence of four types of demulsifier separately. The results showed that an increase in the basic sediment and water content (BS&W) and specific gravity of crude oil has adverse effects on desalting process efficiency.

In recent years, the capabilities of rotating packed beds in dust removal from gases has attracted the attention in different industries. On the other hand, due to intricate complexities of such beds, employment of computational fluid dynamic techniques for design and modeling purposes would be difficult. Therefore, in this research the performance of artificial intelligence techniques in design of theses equipment was investigated. Accordingly, in the first step and by using 561 experimental data points, an artificial neural network system was developed. In the constructed model, dust removal efficiency was considered as the output and the working and design conditions of the bed were fed as the inputs. Performance of the developed system was analyzed both quantitatively and qualitatively and achieving value of 0.99 for correlation coefficient demonstrates its suitable accuracy in efficiency determination. Finally, employing the developed neural network system combined with genetic algorithms, a novel method for optimum design of beds with arbitrary characteristics was proposed. Performed analyses showed that the constructed system while being simple, offers flexibility and precision in design of rotating packed beds. Also, its low coast of development makes it an attractive idea to be employed in industry scale.

Artificial Neural Networks (ANNs) are powerful modeling techniques that work in brief with arrays of neurons in memory and biological learning. In this research, the classification of dynamic and quasi-static loading type (broad and thin edge) was investigated using input data of phenol, antioxidant, vitamin C content and stiffness with artificial neural network. In this experiment for the classification of two Radial basic function and Multilayer perceptron networks were used with two hyperbolic tangent and sigmoid activation functions in one layer. According to the obtained results, the best value for R and Percent Correct for dynamic loading was (Percent Correct = 100 - R = 9999997), loading the thin edge (Percent Correct = 100 - R = 9999993) and loading the wide edge (Percent Correct = 100 - R = 9999992), which was created in the RBF network with a sigmoid function activation and 8 neurons in the one hidden layer. Also, the most accurate data found for the dynamic loading type, the wide edge and the thin edge was observed in the networks created for the RBF network, and this network has been able to 100% accurately classify the data rate for all loads. In sum, the neural network with the input of general data has the desirable capability in the stacking of dynamic loading and quasi-static data.

In this research, general performance of Radial basis function (RBF) Artificial neural networks in experimental data on effect of the NiO, WO3, TiO2,ZnO and Fe2O3 nanoparticles in different temperatures and mass fractions on the viscosity of crude oil has been studied. The morphology and stability of the nanoparticles has been analyzed by DLS and TEM analysis, the results showed that the average diameter of the nanoparticles is from 10 to 30 nm which defers for different oxide nanoparticles. The general method for calculating the optimum span of the Isotropic Gaussian function with special algorithm for learning RBF networks, has been presented. This study's results declared that the RBF artificial neural networks, because of having strong academic basis and having the ability to filter the noises, has a good performance. With increase in temperature, the ratio of the viscosity of the nanofluids decreases compering to the viscosity of the basefluid. Also with increase in nanoparticles mass fraction the related viscosity increases boldly. For temperatures higher than 50°C, the related viscosity is less than the viscosity of the basefluid.

Production-injection optimization has been the subject of various researches due to its complicated and expensive computations. The main reason for this complexity is number of reservoir simulation runs is needed to predict reservoir performance. These numerical reservoir simulations are computationally expensive and time consuming. Therefore, finding a way to reduce the computational burden of reservoir simulation will facilitate the optimization process. One of the methods for reducing the complexity of reservoir simulation is Reduced Order Modeling (ROM) which has been recently introduced for improving efficiency of open source reservoir simulators. In this paper, an ROM method based on Artificial Neural Networks (ANN) and Discrete Empirical Interpolation Method (DEIM) is proposed to resolve the curse of dimensionality while simulating reservoir dynamics with acceptable accuracy. This method is also applicable to black box reservoir simulators. The performance of the suggested ANN-DEIM algorithm has been investigated on a case study on Brugge field. The reduced model well represent the reservoir dynamic behavior while reducing run time by a factor of eight comparing with that of a full order reservoir simulator. ANN-DEIM also has been applied in production-injection optimization of Brugge filed using a Pattern Search optimization algorithm. The proposed method can reduce optimization time by 7 times while leading to %11 improvement in Net Present Value (NPV) over the initial solution used in the optimization process.

Gas viscosity is one of the most important parameters in petroleum engineering affecting fluid flow in porous media, well, and pipelines. Therefore, it is important to use an accurate value in any ranges of operational pressure and temperature. Gas viscosity is measurable in laboratories but it is costly and time consuming. Also, in Iran, there is no apparatus to measure gas viscosity accurately in laboratories; thus engineers rely on empirical correlations to estimate gas viscosity. In this study, a novel method is used to predict hydrocarbon gas viscosity. This new gas viscosity correlation is developed using artificial neural network, statistical techniques, and a non-linear optimization. Moreover, the validation of this correlation has been approved. The results show that this model has more accuracy compared to other ones for a massive data set.

An electrofacies in defined by a similar set of log responses that characterize a specific bed and allow it to be distinguished from other beds. Electrofacies characterization is a simple and cost-effective approach to obtaining permeability estimates in heterogeneous carbonate reservoirs using commonly available well logs. Formation permeability is often measured directly from core samples in the laboratory or evaluated from the well test data. The first method is very expensive. Moreover, the well test data or core data are not available in every well in a field; however, the majority of wells are logged. We propose a two-step approach to permeability prediction from well logs that uses nonparametric regression in conjunction with multivariate statistical analysis. First, we classify the well-log data into electrofacies types. This classification does not require any artificial subdivision of the data population and it follows naturally based on the unique characteristics of well-log measurements reflecting minerals and lithofacies within the logged interval. A combination of principal components analysis (PCA), model-based cluster analysis (MCA), and discriminant analysis is used to characterize and identify electrofacies types. Second, we apply nonparametric regression techniques to predict permeability using well logs within each electrofacies. Three nonparametric approaches are examined, namely alternating conditional expectations (ACE), support vector machine (SVM), and artificial neural networks (ANN), and the relative advantages and disadvantages are explored. For permeability predictions, the ACE model appears to outperform the other nonparametric approaches. We applied the proposed technique to a highly heterogeneous carbonate reservoir in the southwest of Iran.

The widespread and daily increasing application of heterogeneous catalysts in the industry has caused to using new techniques in catalysts design for reducing costs and accelerating research, development and commercialization. The application of combinatorial catalysis methods as new techniques in catalysts design are under development. At this paper, combinatorial catalysis methods including of experimental design, genetic algorithm and meta-modeling has been reviewed.