Computation of the integral parameters of turbulent structures for the transient gas flows in pipes using wavelet transforms

Turbulent structures of simulated two-dimensional gas flows in a convergent-tube assembly of a complex pipe are analyzed by computing the morphometric parameters for the texture of two-dimensional energy fields using wavelet transforms. A new computer-aided procedure based on the decomposition of the original image of a gas flow into low-and high-frequency components using a discrete wavelet transform, calculation of the textural parameters for the high-frequency component, binary decomposition, and calculation of the morphometric parameters for the textured images is developed to analyze the flow pattern of the turbulence of transient gas flows in the assemblies of complex pipes. A new system of integral parameters computed on the basis of the binary decomposition of the textured images of gas-flow characteristics and the morphometric measurements of the parameters of flow objects in binarization sections is proposed to characterize the turbulent structure of transient gas flows in pipes.     

Wavelet morphometric neural network algorithm for analyzing nanomaterial porous texture

A wavelet morphometric neural network algorithm for analyzing the porous texture of a nanomaterial that differs from the use of the procedure for identifying the binary clusters for the morphometric analysis obtained as a result of the analysis of the neural network cluster of a micro photo image of a nanomaterial instead of the procedure for identifying binary objects on binary cross sections of the original micro photo image have been proposed. Using this algorithm, we calculated the quantitative morphometric estimations of the geometric parameters of the nanocluster texture of solid and porous components, which have been applied to predict the density distribution of pores inside of a nanomaterial.     

Computer-aided method of analysis of nanocomposite structure on the basis of calculations of isolines of fractal dimensionality

A computer-aided method of analysis of nanocomposite textures on the basis of calculation of the fractal dimensions of nanostructures using microphotographs of the nanocomposites is proposed. The computer-aided method of assessment of the fractal dimensions is notable for the use of an algorithm of calculation of the self-similarity indices of the power spectra of two-dimensional luminance fields of the nanostructure imaging on microphotographs and the use of the box-counting algorithm for measurement of the fractal dimensions. This method makes it possible to assess the rates and directions of cluster growth in the nanocomposite texture. On the basis of numerous computer experiments using the method proposed, we have ascertained that dark zones of two types are present on microphotographs of the texture of the nanocomposites obtained by sedimentation of tin oxides and formation of fine-particle silicon carbide: homogeneous zones, where there is no manifestation of the fine structure of the nanocomposites, and indistinctly contoured structured zones that hypothetically can correspond to the formation of new clusters or ensembles of nanoparticles.     

Polymer powders mixing part II: Multi-component mixing dynamics using RGB color analysis

In this work, the mixing quality of a multi-component blend of particles is determined using Multivariate Image Analysis of RGB images combined with the Grey Level Co-occurrence Matrix (GLCM) texture analysis. The mixing dynamics and flow behavior are studied in terms of mixing homogeneity and time to achieve equilibrium for binary, ternary and quaternary mixtures of equal size particles. The parameters studied are rotational speed, filling ratio, initial powder composition and particle sizes. Using the experimental data in the rolling regime, a second order model is proposed to predict the mixing curve as a function of time.     

基于复杂网络时空特性的泡沫图像动态纹理特征分析

基于机器视觉的浮选过程监控方法已经被广泛应用于浮选过程中,泡沫表面纹理特征是过程监控的关键视觉特征之一。当前静态纹理特征只能从空间维度描述图像特征,在时间维度上刻画图像序列的内在变化特性存在不足,不能准确反映浮选泡沫浮选过程动态特性。提出了基于复杂网络时空特性的泡沫图像序列动态纹理特征方法。通过将每帧图像的像素点映射到网络各节点,利用邻接矩阵建立复杂网络模型和网络权值动态演化反应不同时刻的图像特征,基于复杂网络时空特性提取泡沫图像序列的动态纹理特征。结合实际生产数据进行仿真验证,实验结果表明该方法可准确识别浮选动态状况,为浮选生产过程的实时调节提供重要的指导信息。     

基于图像动态纹理特征的气固流化床流型识别

准确识别流型是气固流化床二相流参数检测的重要内容,文中提出一种基于图像光流法和动态纹理特征相 结合的气固流化床流型识别的新方法.实验是在气固流化床二相流实验系统上利用高速摄影系统获取流型图像.流型图像分别为鼓泡床,节涌床,湍动床,快速流化床,稀相输送等5种典型流型.首先对获取的不同流型图像分别进行去噪和对比度拉伸...     

基于图像的皮肤纹理评价算法研究

皮肤表面纹理或微轮廓的量化评价对抗皱宣称的化妆品功效评价有重要意义。基于皮肤美容领域的应用需求和日常生活的实际需要,结合图像处理领域的相关算法,对皮肤的基础纹理特征展开了研究。首先,将实验实测的皮肤图像转为灰度图像,再通过对比度受限的自适应直方图均衡化对图像进行增强,之后通过高斯滤波去除图像的噪声,再采用维纳滤波对纹理的细节信息进行增强,得到纹理清晰的皮肤图像。通过实验确定适合于皮肤纹理评价的灰度共生矩阵的灰度级数和距离,基于灰度共生矩阵算法对皮肤纹理进行统计分析,提出了基于4个纹理特征参数的综合指标数学模型,并应用该模型对全部皮肤图像进行了纹理特征定量评价,同时也由专家对这些皮肤图像进行视觉盲评,2种评价方法一致性良好。     

Determination of steel quality based on discriminating textural feature selection

Image data can be acquired from a product surface in real time by image sensor systems in chemical plants. For quality determination based on these image datasets, effective texture classification methodology is essential to handle highly dimensional images and to extract quality-related information from these product surface images.Wavelet texture analysis is useful for reducing the dimension and extracting textural information from images. Although wavelet texture analysis extracts only textural characteristics from images, the extracted features still contain unnecessary information for classification. The texture analysis method can be improved by retaining only class-dependent features and removing common features. In previous works, best basis and local discriminant basis are the most popular techniques for selecting an important basis from the wavelet packet basis. However, feature selection based on wavelet texture analysis has been studied for texture classification. Because previous methods are designed for wavelet coefficients with features for analysis, their performance is poor with wavelet texture analysis.We propose a novel texture classification methodology for quality determination based on feature selection using wavelet texture analysis. The proposed methodology applies the sequential forward floating selection (SFFS) algorithm as a feature selection strategy to select discriminating wavelet signatures using wavelet texture analysis. The proposed methodology is validated through quality determination for industrial steel surfaces. The results show that the proposed method has fewer classification errors with fewer number of features than previous methods.     

基于知识本体的HAZOP信息标准化框架

大量的危险与可操作性分析（hazard and operability analysis,HAZOP）报告以纸质文档形式保存,难于复用、共享,同时基于计算机软件的分析结果也只有对应的分析软件才能识别,同样存在难于复用、共享的问题。针对此问题,本文提出了基于知识本体的HAZOP信息标准化框架。该框架以知识本体和HAZOP分析国际标准IEC 61882为基础,抽提归纳了HAZOP的标准化信息模型,给出了模型的整体结构、模型中各元素的定义与关系。并在此基础上,提出了HAZOP信息标准化方法,采用BiLSTM神经网络对每一条HAZOP分析的记录进行标注、训练与识别,实现了人工HAZOP分析结果的自动识别与标准化。以某油品合成装置为例,对HAZOP信息标准化方法进行了验证,结果表明基于知识本体的HAZOP信息标准化框架可以自动实现分析结果的标准化,便于分析知识的共享与复用。     

Texture and fractal analysis of silica-alumina glass ceramics

Using electron-microscopy micrographs, texture and fractal characteristics of the microstructure of silica-alumina glass ceramics are calculated at different temperatures. The relationship between the numerical characteristics of the intensity of liquation and crystallization processes of aluminosilicate glass ceramic samples and their thermal coefficients of linear expansion with the values of the fractal dimension and its derivatives is established for photomicrographs of the studied heat-treated samples.     

非电解质液体混合物表面张力的统计热力学模型

运用Davis模型导出一个统计热力学的表面张力模型．对22个双组分体系的表面张力作了推算和关联,总平均相对偏差分别为5.45％和1.95％.并利用关联双组分体系得到的参数值,直接推测了三组分体系的表面张力,平均相对偏差为2.21％.结果令人满意.表明该方法简单、精确,便于工程应用．     

A simple thermo-physical model for vapor–liquid equilibrium of the reactive HIx (HI–H2O–I2–H2) system

Thermodynamic phase equilibrium of the reactive HIx system encountered in the sulfur-iodine (SI) cycle has been identified as a basic research need for the hydrogen economy. In this communication, a simple NRTL (nonrandom two-liquid)-based vapor–liquid equilibrium (VLE) model is devised for the HIx system considering the HI decomposition reaction in the gas phase only. We propose a new set of NRTL binary interaction parameters as well as a new expression for the HI decomposition chemical equilibrium constant as a function of temperature. This simple VLE model with the use of only one set of NRTL binary parameters is capable of reproducing the Larousse et al. (Int. J. Hydrogen Energy 34 (2009) 3258–3266) experimental data for a wide range of pressures (1–24 bar) and HI concentrations beyond the azeotrope.     

Modeling of diffusion-controlled free-radical polymerization reactions

The present paper introduces a new fundamental approach to the modeling of diffusion-controlled free-radical polymerization reactions. Our analysis follows the original work of Chiu, Carratt, and Soong (CCS), according to which the termination and propagation rate constants are expressed in terms of both a purely reaction-limited term and a diffusion-limited one. The contribution of the latter term to the apparent rate constants is described in terms of the polymer and monomer effective diffusion coefficients and an effective reaction radius. It is shown that all parameters appearing in the original CCS model can be calculated from first principles using available data on the physical and transport properties of a particular monomer–polymer binary system. The generalized free volume theory of Vrentas and Duda and the theory of excess chain end mobility are invoked for the calculation of the effective diffusion coefficients and the reaction radius, respectively. The approach followed in this study is general and needs only the specification of one unknown parameter with a clear physical meaning. All other parameters can be readily calculated from available data. The ability of the new model to predict molecular weight developments and monomer conversion in diffusion-controlled reactions is demonstrated by application of the proposed model equations to the bulk polymerization of MMA.     

An algorithm for the optimization of kubelka-munk absorption and scattering coefficients

A new approach to the calculation of Kubelka-Munk absorption and scattering coefficients based on linear-leastsquares techniques is proposed. This algorithm characterizes colorants by determining the coefficients from typical mixtures. Several advantages are gained over traditional methods: Absorption and scattering can be determined without use of primary binary mixtures by using production-mixture history; colorants are characterized in the same manner in which they are used; and the approach is quite flexible in terms of manipulating the calculation.     

A Quantitative Analysis of the Ensemble of Bubbles in a Silicate Melt Layer Using an Image Analyzer

A method is proposed for an automatic determination of the quantitative parameters of an ensemble of gas bubbles in a viscous melt. This method is implemented in an image analysis software–hardware complex. For implementation of this method, a special algorithm for recognizing gas bubbles in images of the viscous melt is developed. The quantitative characteristics of gas bubbles in the viscous melt are determined, and the reliability of the obtained data is evaluated using the proposed method.     

基于多项式趋势面分析的油井初期产量预测

油井初期产量是编制油田开发方案的重要参数,而油气储层的物性特征是油井初期产量的主控因素。根据已知油井初期产量、油气储层孔隙度和渗透率,通过最优拟合原则建立油井初期产量与油气储层孔隙度和渗透率最佳预测数学模型,基于预测数学模型对未知油井初期产量进行预测分析。结果表明,基于趋势面分析的油井初期产量预测方法是可行,其结果可靠,可以为油田编制开发方案提供参考依据。     

On the thermodynamics of concentrated strong electrolytes aqueous solutions the system NaNO3—NaCl—H2O

A simple analytical function is proposed for the calculation of molar excess Gibbs energy of binary solutions of strong electrolytes in water. Empirical parameters can be easily determined from experimental data reported in the literature. The treatment is extended to ternary solutions and to solid liquid equilibria using an empirical equation. Absence of solid solutions is assumed. The correlations are applied to the common ion ternary system NaNO₃-NaCl-H₂O in the temperature range from 0 to 100°C. Predictions of activity coefficients of the binary systems and saturation curves of the ternary system are in good agreement with experimental data.     

ON THE COMPOSITION-DEPENDENT INTERACTION PARAMETERS IN EQUATIONS OF STATE

Composition-dependent interaction parameters have been applied to the calculation of vapor-liquid equilibria (VLE) in mixtures containing components of different chemical nature. Binary VLE have been correlated and ternary VLE have been predicted from binary data using five different mixing rules. Binary data can be accurately correlated for systems with moderate deviations from ideality using mixing rules with two binary parameters. For very strongly nonideal mixtures three binary parameters are needed. For the prediction of ternary VLE from binary information only the mixing rules of Panagiotopoulos and Reid (1986) and Schwartzentruber et al. (1987) are reliable. For most systems the quality of predicting ternary data is comparable to the quality of correlating binary data. Significant deviations are noted only for strongly nonideal systems close to phase separation. In these cases it is recommended to use models incorporating association in an explicit form. KEYWORDS Equations of state Mixing rules Multicomponent Vapor-liquid equilibria.     

Algorithm for solving problems related to the natural vibrations of electro-viscoelastic structures with shunt circuits using ANSYS data

ABSTRACT

An algorithm for numerical realisation of a mathematical statement of the natural vibrations problem for electro-viscoelastic bodies with passive external electric circuits (i.e. shunting circuits) with an arbitrary configuration using the finite element method is proposed in the present paper. The proposed algorithm allows considering the viscoelastic properties of materials using the model of linear hereditary viscoelasticity with complex dynamic moduli and is used to solve 3D solid structure problems that are compatible for ANSYS package element types. This technique implies the usage of the global assembled matrices of stiffness and mass, formed in the ANSYS package. The basis of the algorithm is a novel approach that allows performing decomposition of the global assembled stiffness matrix formed in the ANSYS software package into constituents that are needed for calculation of the natural vibration frequencies of the objects under study. These matrix components are used in the program that was written in FORTRAN (Formula Translation) language. This problem could be efficiently applied for analysis of the dynamic processes in smart systems based on piezoelectric materials and could also form a basis for the development of numerical finite element algorithms for optimization of the dissipative characteristics of electromechanical systems with shunted piezoelectric elements.     

城市燃气中长期负荷的灰色预测

针对中长期城市燃气预测中时间跨度大、燃气需求增长不稳定的特性,提出了利用序列缓冲算子对原始数据进行弱化处理,再建模型的方法。通过仿真计算结果验证了该方法的正确性和有效性。