Prediction of swelling pressures of expansive soils using artificial neural networks

Swelling behavior of expansive soil is a complicated phenomenon. In order to cope with the complications in describing the swelling behavior of expansive soil, researchers developed alternative approaches. In this paper, the prediction model of transmitted lateral swelling pressure, and vertical swelling pressures on a retaining structure was developed using artificial neural network (ANN) approach. In the first stage of this study, the lateral and vertical swelling pressures were measured with different thicknesses of expanded polystyrene (EPS) geofoam placed between one of the vertical walls of the steel testing box and the expansive soil. Then, artificial neural network was trained using these pressures for prediction transmitted lateral swelling pressure, and vertical swelling pressures on a retaining structure. Results obtained from this study showed that neural network-based prediction models could satisfactorily be used in obtaining the swelling pressures of the expansive soils.     

Approximating support vector machine with artificial neural network for fast prediction

Support vector machine (SVM) is a powerful algorithm for classification and regression problems and is widely applied to real-world applications. However, its high computational load in the test phase makes it difficult to use in practice. In this paper, we propose hybrid neural network (HNN), a method to accelerate an SVM in the test phase by approximating the SVM. The proposed method approximates the SVM using an artificial neural network (ANN). The resulting regression function of the ANN replaces the decision function or the regression function of the SVM. Since the prediction of the ANN requires significantly less computation than that of the SVM, the proposed method yields faster test speed. The proposed method is evaluated by experiments on real-world benchmark datasets. Experimental results show that the proposed method successfully accelerates SVM in the test phase with little or no prediction loss.     

基于Logistic回归、ANN、SVM的乳腺癌复发影响因素研究

为找出乳腺癌复发的影响因素,并比较人工神经网络（ANN）型、支持向量机型（SVM）和logistic回归型在乳腺癌复发中的预测效能.本文结合南斯拉夫卢布尔雅那大学医疗中心乳腺癌肿瘤研究所的277例数据,对乳腺癌复发的影响因素进行研究.分别采用了logistic回归、人工神经网络和支持向量机方法来建立乳腺癌复发的预测模型,并对这三种分析方法进行了理论方法和预测效能的比较.结果发现,肿瘤大小、有无结节冒、肿瘤恶性程度（P<0.05）是乳腺癌术后复发的主要影响因素,而在不同的预测方法中相对于logistic回归模型,支持向量机和人工神经网络具有更好的预测效能,其中支持向量机的预测效能最好.     

油田产量多变量预测模型的优化

油田开发是一个复杂的多变量非线性动力学系统,为有效地预测油田产量,确保油田生产过程高产稳产,该文提出采用多元线性回归与神经网络相结合的方法对油田产量多变量预测模型进行优化。首先基于回归分析的“后退法”对影响产量的变量进行优选,然后通过神经网络对优选后的变量进行训练得到最终的预测模型,从而实现神经网络与多元线性回归相结合建立多变量预测模型。实际应用结果表明,优化后的模型简洁实用,可以在一定程度上提高模型的预测精度,并减少建模预测所需数据量。     

A comparative study of artificial neural networks,and decision trees for digital game content stocks price prediction

Precise prediction of stock prices is difficult chiefly because of the many intervening factors. Unpredictability is particularly notable in the aftermath of the global financial crisis. Data mining may however be used to discover highly correlated estimation models. This study looks at artificial neural networks (ANN), decision trees and the hybrid model of ANN and decision trees (hybrid model), the three common algorithm methods used for numerical analysis, to forecast stock prices. The author compared the stock price forecasting models derived from the three methods, and applied the models on 10 different stocks in 320 data sets in an empirical forecast. Average accuracy of ANN is 15.31%, the highest, in terms of match with real market stock prices, followed by decision trees, at 14.06%; hybrid model is 13.75%. The study also discovers that compared to the other two methods, ANN is a more stable method for predicting stock prices in the volatile post-crisis stock market.     

The prediction of heating energy consumption in a model house by using artificial neural networks in Denizli–Turkey

Turkey does not have petrol and natural gas reserves on a large scale. National energy resources are lignite and hydropower. Together with increasing environmental problems and diminishing fossil resources, studies focusing on energy reduction as well as usage of renewable energy resources have accelerated. However, taking the technological and economical impossibilities into account, the most logical solution is energy saving by providing energy efficiency in households. In this study, an artificial neural network (ANN) model is developed in order to predict hourly heating energy consumption of a model house designed in Denizli which is located in Central Aegean Region of Turkey. Hourly heating energy consumption of the model house is calculated by degree-hour method. ANN model is trained with heating energy consumption values of years 2004–2007 and tested with heating energy consumption values of year 2008. The training and test figures were depicted for February month of these years. Best estimate is found with 29 neurons and a good coherence is observed between calculated and predicted values. According to the results obtained, root-mean-squared error (RMSE), absolute fraction (R²) and mean absolute percentage error (MAPE) values are 1.2575, 0.9907, and 0.2091 for training phase and 1.2125, 0.9880, and 0.2081 for testing phase respectively.     

Artificial neural network and wavelet neural network approaches for modelling of a solar air heater

This paper reports on a modelling study of new solar air heater (SAH) system by using artificial neural network (ANN) and wavelet neural network (WNN) models. In this study, a device for inserting an absorbing plate made of aluminium cans into the double-pass channel in a flat-plate SAH. A SAH system is a multi-variable system that is hard to model by conventional methods. As regards the ANN and WNN methods, it has a superior capability for generalization, and this capability is independent on the dimensionality of the input data’s. In this study, an ANN and WNN based methods were intended to adopt SAH system for efficient modelling. To evaluate prediction capabilities of different types of neural network models (ANN and WNN), their best architecture and effective training parameters should be found. The performance of the proposed methodology was evaluated by using several statistical validation parameters. Comparison between predicted and experimental results indicates that the proposed WNN model can be used for estimating the some parameters of SAHs with reasonable accuracy.     

Prediction of wind-induced pressures on a large gymnasium roof using artificial neural networks

The application of artificial neural networks (ANNs) to solve wind engineering problems has received increasing interests in recent years. This paper is concerned with developing two ANN approaches (a backpropagation neural network [BPNN] and a fuzzy neural network [FNN]) for the prediction of mean, root-mean-square (rms) pressure coefficients and time series of wind-induced pressures on a large gymnasium roof. In this study, simultaneous pressure measurements are made on a large gymnasium roof model in a boundary layer wind tunnel and parts of the model test data are used as the training sets for developing two ANN models to recognize the input–output patterns. Comparisons of the prediction results by the two ANN approaches and those from the wind tunnel test are made to examine the performance of the two ANN models, which demonstrates that the two ANN approaches can successfully predict the pressures on the entire surfaces of the large roof on the basis of wind tunnel pressure measurements from a certain number of pressure taps. Moreover, the FNN approach is found to be superior to the BPNN approach. It is shown through this study that the developed ANN approaches can be served as an effective tool for the design and analysis of wind effects on large roof structures.     

Study of corporate credit risk prediction based on integrating boosting and random subspace

With the rapid growth and increased competition in credit industry, the corporate credit risk prediction is becoming more important for credit-granting institutions. In this paper, we propose an integrated ensemble approach, called RS-Boosting, which is based on two popular ensemble strategies, i.e., boosting and random subspace, for corporate credit risk prediction. As there are two different factors encouraging diversity in RS-Boosting, it would be advantageous to get better performance. Two corporate credit datasets are selected to demonstrate the effectiveness and feasibility of the proposed method. Experimental results reveal that RS-Boosting gets the best performance among seven methods, i.e., logistic regression analysis (LRA), decision tree (DT), artificial neural network (ANN), bagging, boosting and random subspace. All these results illustrate that RS-Boosting can be used as an alternative method for corporate credit risk prediction.     

基于支持向量机回归的麻醉药毒性的QSPR研究

采用支持向量机回归(SVR)方法研究了39个麻醉药毒性的定量构效关系,基于留一法交叉验证的结果,模型的相关系数为0.970。结果表明,所建SVR模型的精度高于逆传播人工神经网络(BPANN)、多元线性回归(MLR)和偏最小二乘法(PLS)所得的结果。     

运用线性和非线性的方法预测烷基苯的沸点和摩尔体积(英文)

本文中建立了几个定量的模型预测80个烷基苯的沸点和79个烷基苯的摩尔体积.每个烷基苯的结构用其分子式得到的6个数字编码来描述.把这6个数字编码作为捕述符,运用多元线性回归,多元非线性回归和人工神经网络地方法来分别建立定量构效关系模犁.模型具有很好的预测性.沸点的3个预测模型,RMS偏差都小于9℃,摩尔体积的3个预测模型的RMS偏差都小于6 cm3·mol-1.     

双酚A型聚碳酸酯快速拉伸过程的分子动力学模拟

本文采用用分子动力学方法研究了双酚A型聚碳酸酯的快速拉伸过程.采用COMPASS力场和NPT系综研究了应力应/变关系、能量/应变关系等.应力-应变曲线的研究结果显示,前"屈服点"和后"屈服点"分别为0.14和0.17,应变≤0.05为"弹性区域".0.14<ε_(xx)<1.05的区域为"塑性区域",ε_(xx)>1.05属于"硬化"区.能量-应力关系的研究结果显示,在应力-应变呈线性关系的"弹性区域",体系的总势能及各势能分量随应变增大发生不规则的波动.为了从能量的角度解释PBC-PC在外部拉伸条件下的应变情况,本文还研究了体系总能量与各能量分项,与应变的关系,对链结构与能量分项的关系进行了讨论.     

电力负荷短期预测的支持向量回归参数自动赋值研究

电力系统负荷预测是当前国内外的研究热点,支持向量回归算法是一种解决电力系统负荷预测问题非常有效的方法,如何根据特定数据集选择合适的模型参数,以保证建立好的模型有很好的推广性能,成为设计支持向量回归机的关键一步。本文采用了1-范数、2-范数以及v-支持向量回归算法来解决支持向量机参数的自动复制问题。在真实数据集上的实验结果表明,新模型在预测能力上较之一些广泛使用的软件可靠性预测模型有明显的提高。     

Multiple regression,ANN and ANFIS models for prediction of backbreak in the open pit blasting

Backbreak is one of the undesirable effects of blasting operations causing instability in mine walls, falling down the machinery, improper fragmentation and reduction in efficiency of drilling. Backbreak can be affected by various parameters such as the rock mass properties, blasting geometry and explosive properties. In this study, the application of the artificial neural network (ANN), an adaptive neuro-fuzzy inference system (ANFIS) for prediction of backbreak, was described and compared with the traditional statistical model of multiple regression. The performance of these models was assessed through the root mean square error, correlation coefficient (R ²) and mean absolute percentage error. As a result, it was found that the constructed ANFIS exhibited a higher performance than the ANN and multiple regression for backbreak prediction.     

人工神经网络在煤氧化性预测方面的研究

提出了利用人工神经网络技术进行煤氧化速率定量预测的新方法．根据对煤自燃的实际特点和基本规律的综合考虑，研究了影响因素的选取、煤氧化速率预测模型的建立等问题。采用BP神经网络算法对煤氧化速率进行了建模。结果表明，用神经网络模型对煤氧化速率进行模拟预测，具有理论上的可行性和现实意义，说明人工神经网络技术在煤氧化速率预计领域中具有实用价值。     

Neural network-based failure rate prediction for De Havilland Dash-8 tires

An artificial neural network (ANN) model for predicting the failure rate of De Havilland Dash-8 airplane tires utilizing the two-layered feed-forward back-propagation algorithm as a learning rule is developed. The inputs to the neural network are independent variables and the output is the failure rate of the tires. Six years of data are used for model building and validation. Model validation, which reflects the suitability of the model for future prediction is performed by comparing the predictions of the model with that of Weibull regression model. The results show that the failure rate predicted by the ANN is closer in agreement with the actual data than the failure rate predicted by the Weibull model.     

人工神经网络方法研究含硫芳香衍生物毒性与结构的关系

结合逐步线性回归方法与人工神经网络方法，研究了含硫芳香衍生物对发光细菌毒性的构效关系，充分表明了两个方法的互补，回归方法为网络方法提供变量的物理解释，网络方法建立精确的构效关系模型，人工神经网络方法在非线民生较强的构效关系研究中起到重要的作用，基于交叉检验，本文还提出了防止人工神经网络方法过拟合现象发生的ｒ判据，对于建立较好的预报模型，具有一定的普遍意义。     

Applications of artificial neural networks to the nonlinear combination of forecasts

Abstract: This paper proposes artificial neural networks (ANN) as a tool for nonlinear combination of forecasts. In this study, three forecasting models are used for individual forecasts, and then two linear combining methods are used to compare with the ANN combining method. The comparative experiment using real-world data shows that the prediction by the ANN method outperforms those by linear combining methods. The paper suggests that the ANN method can be used as an alternative to conventional linear combining methods to achieve greater forecasting accuracy.     

A comparison of neural networks and adaptive neuro-fuzzy inference systems for the prediction of water diffusion through carbon nanotubes

Given the fact that artificial intelligence tools such as neural network and fuzzy logic are capable of learning and inferencing from the past to capture the patterns that exist in the data, this study presents an intelligent method for the forecasting of water diffusion through carbon nanotubes where predictions are generated from neuro-fuzzy structures using molecular dynamics data. Therefore, this research was mainly focused on combining molecular dynamics with artificial intelligence methods in order to reduce the computational time of biomolecular and nanofluidic simulations. Two different artificial intelligence methods are applied for the time-dependent water diffusion forecasting: artificial neural network (ANN) and adaptive neuro-fuzzy inference systems (ANFISs). The effects of different sizes of training sample sets on forecasting performance of ANN and ANFIS are investigated as well. Four different evaluation methods are used to measure the performance and forecasting accuracy of these two methods. As a result, ANFIS presents the higher accuracy than neural network method based on the comparison of these different evaluation methods adopted in this research. The results reported in this research demonstrate that combining of molecular dynamics with artificial intelligence methods can be one of the most powerful and beneficial tools for prediction of important nanofluidic parameters.     

Application of wrapper approach and composite classifier to the stock trend prediction

The research on the stock market prediction has been more popular in recent years. Numerous researchers tried to predict the immediate future stock prices or indices based on technical indices with various mathematical models and machine learning techniques such as artificial neural networks (ANN), support vector machines (SVM) and ARIMA models. Although some researches in the literature exhibit satisfactory prediction achievement when the average percentage error and root mean square error are used as the performance metrics, the prediction accuracy of whether stock market goes or down is seldom analyzed. This paper employs wrapper approach to select the optimal feature subset from original feature set composed of 23 technical indices and then uses voting scheme that combines different classification algorithms to predict the trend in Korea and Taiwan stock markets. Experimental result shows that wrapper approach can achieve better performance than the commonly used feature filters, such as χ²-Statistic, Information gain, ReliefF, Symmetrical uncertainty and CFS. Moreover, the proposed voting scheme outperforms single classifier such as SVM, kth nearest neighbor, back-propagation neural network, decision tree, and logistic regression.