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Article
Publication date: 6 February 2018

Li Wang and Qingpu Zhang

Internet-based intangible network good (IING) has revolutionized multiple industries in recent years. This paper aims to reveal the laws of consumer’s decision-making on IING from…

Abstract

Purpose

Internet-based intangible network good (IING) has revolutionized multiple industries in recent years. This paper aims to reveal the laws of consumer’s decision-making on IING from a perspective of kinetic energy and potential energy.

Design/methodology/approach

In this paper, 4 aspects and 17 factors influencing IING adoption were generalized. Based on the theory of social physics, an agent-based simulation model, introducing physical energy theory to depict consumer’s decision-making, was built. An agent’s kinetic energy reflects the agent’s perceived effect of mass media on the agent’s decision-making on IING adoption. An agent’s potential energy reflects the agent’s perceived effect of social interactions on the agent’s decision-making on the adoption of IING. An agent’s final energy is the sum of the kinetic energy and potential energy, which reflects the agent’s final decision.

Findings

Some factors mainly influence the diffusion velocity, while other factors have a dramatic impact on both diffusion velocity and diffusion scale. The agent’s personality can make a difference at the early and middle stages of IING adoption, but a faint impact at the later stage because of the effects of network externalities and word of mouth. There is a critical value of the number of initial adopters which can dramatically speed up IING adoption.

Practical implications

This study provides new insights for firms on the effects of factors influencing consumers’ decision-making on IING adoption.

Originality/value

This paper defines a new kind of innovation, IING, and generalizes IING’s special characteristics. As a new application of social physics, the physical energy theory has been creatively introduced to depict consumer’s decision-making on IING adoption. A kinetic and potential energy model of IING adoption has been built. Based on simulation experiments, new insights of IING adoption have been gained.

Article
Publication date: 1 February 2006

C.M. Winkler and Sarma L. Rani

To evaluate the performance of different subgrid kinetic energy models across a range of Reynolds numbers while keeping the grid constant.

Abstract

Purpose

To evaluate the performance of different subgrid kinetic energy models across a range of Reynolds numbers while keeping the grid constant.

Design/methodology/approach

A dynamic subgrid kinetic energy model, a static coefficient kinetic energy model, and a “no‐model” method are compared with direct numerical simulation (DNS) data at two friction Reynolds numbers of 180 and 590 for turbulent channel flow.

Findings

Results indicate that, at lower Reynolds numbers, the dynamic model more closely matches DNS data. As the amount of energy in the unresolved scales increases, the performance of both kinetic energy models is seen to decrease.

Originality/value

This paper provides guidance to engineers who routinely use a single grid to study a wide range of flow conditions (i.e. Reynolds numbers), and what level of accuracy can be expected by using kinetic energy models for large eddy simulations.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 16 no. 2
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 19 May 2023

Zeliha Betül Kol and Dilek Duranoğlu

This study aims to model and investigate Basic Yellow 28 (BY28) adsorption onto activated carbon in batch and continuous process.

Abstract

Purpose

This study aims to model and investigate Basic Yellow 28 (BY28) adsorption onto activated carbon in batch and continuous process.

Design/methodology/approach

Batch adsorption experiments were carried out at 25 °C with 50 mg/L BY28 solution at pH 6 with different amounts of activated carbon. Freundlich and Langmuir adsorption isotherm models were used to model batch data. Pseudo-first-order and pseudo-second-order kinetic models were applied with linear regression. The changes of the breakthrough curve with the column height, flow rate, column diameter and adsorbent amount were examined in fixed bed column at room temperature. BY28 adsorption data were modelled by using different adsorption column models (Adams & Bohart, Thomas, Yoon & Nelson, Clark and modified dose–response) with non-linear regression.

Findings

Freundlich model and pseudo-second-order kinetic model expressed the experimental data with high compatibility. Modified dose-response model corresponded to the fixed bed column data very well.

Originality/value

Adsorption of Basic Yellow 28 on activated carbon in a fixed bed column was studied for the first time. Continuous adsorption process was modelled with theoretical adsorption models using non-linear regression.

Details

Pigment & Resin Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 10 December 2019

Akbar Eslami, Zahra Goodarzvand Chegini, Maryam Khashij, Mohammad Mehralian and Marjan Hashemi

A nanosilica adsorbent was prepared and characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and BET.

Abstract

Purpose

A nanosilica adsorbent was prepared and characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and BET.

Design/methodology/approach

The optimum conditions for the highest adsorption performance were determined by kinetic modeling. The adsorbent was used for the adsorption of acetaminophen (ACT), and the parameters affecting the adsorption were discussed like pH, initial concentration, contact time and adsorbent dosage. The adsorbent have been characterized by SEM, XRD and BET analysis. The kinetic models including pseudo-first-order and pseudo-second-order with Langmuir and Freundlich isotherm models were applied to investigate the kinetic and isotherms parameters.

Findings

The adsorption of ACT increased to around 95% with the increase of nanosilica concentration to 30 g/L. Moreover, the adsorption process of ACT follows the pseudo-second-order kinetics and the Langmuir isotherm with the maximum adsorption capacity of 609 mg/g.

Practical implications

This study provided a simple and effective way to prepare of nanoadsorbents. This way was conductive to protect environmental and subsequent application for removal of emerging pollutants from aqueous solutions.

Originality/value

The novelty of the study is synthesizing the morphological and structural properties of nanosilica-based adsorbent (specific surface area, pore volume and size, shape and capability) and improving its removal rate through optimizing the synthesis method; and studying the capability of synthesis of nanosilica-based adsorbent for removal of ACT as a main emerging pharmaceutical water contaminant.

Details

Pigment & Resin Technology, vol. 49 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 July 2004

A. Mitter, J.P. Malhotra and H.T. Jadeja

A modelling approach of gas solid flow, considering different physical phenomenon such as fluid turbulence, particle turbulence and interparticle collision effects are presented…

Abstract

A modelling approach of gas solid flow, considering different physical phenomenon such as fluid turbulence, particle turbulence and interparticle collision effects are presented. The approach is based on the two‐fluid model formulation where both phases are treated as continuum. This implies that the gas phase as well as the particle phase are weighted by their separate volumetric fractions. According to the experimental results and numerical simulations, the inter‐particle collision possesses a significant influence of turbulence level on particle transport properties in gas solid turbulent flow even for dispersed phase volume fraction (α<0.01). Comparisons in predictions have been depicted with inclusion of interparticle collision effect in the equation of particle turbulent kinetic energy and with exclusion of this effect. Experimental research has been conducted in a thermal power plant depicting higher erosion resistance of noncircular square sectioned coal pipe bends in comparison with those with circular cross section, the salient features of the experimental work are presented in this paper. Experiments have been conducted to determine, pressure drop in straight and curved portions of conduits conveying air coal mixtures in a thermal power plant. Validation of this experimental data with numerical predictions have been presented.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 14 no. 5
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 February 1995

Shuichi Torii and Wen‐Jei Yang

A numerical study is performed to investigate turbulent flowcharacteristics in a pipe rotating around the axis. Emphasis is placed on theeffect of pipe rotation on the friction…

Abstract

A numerical study is performed to investigate turbulent flow characteristics in a pipe rotating around the axis. Emphasis is placed on the effect of pipe rotation on the friction coefficient and velocity distribution in the hydrodynamically, fully‐developed flow region. The k—ε turbulence model is modified by taking the swirling effect into account, in which the model function including the Richardson number is introduced to the ε equation. The governing boundary‐layer equations are discretized by means of a control volume finite‐difference technique for numerical computation. Results obtained from the modified model agree well with experiment data in the existing literature. It is found from the study that (i) an axial rotation of the pipe induces an attenuation in the turbulent kinetic energy, resulting in a reduction in the friction coefficient, the turbulent and (ii) an increase in the velocity ratio causes substantial decreases in the friction coefficient, the turbulent kinetic energy and the streamwise velocity gradient near the wall.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 5 no. 2
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 January 2008

A. Touati, S. Corbel and J.P. Corriou

Photolithography allows the fabrication of a solid polymer object through polymerization of a monomer resin by means of a laser source guided according to the data of computer…

Abstract

Photolithography allows the fabrication of a solid polymer object through polymerization of a monomer resin by means of a laser source guided according to the data of computer aided design. However, one drawback of this method is the inaccuracy of the dimensions of the objects related to the shrinkage phenomenon which depends on the polymerization, on the laser flux and on the used sweeping procedure. In this paper, the deformation of an isolated voxel (elementary volume) or a voxel interacting with its neighbor is described. This simulation is based on a kinetic model that takes into account the gel effect and a model of volumetric variation due to the difference of the length of the bonds between the monomer and polymer molecules.

Details

Multidiscipline Modeling in Materials and Structures, vol. 4 no. 1
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 17 October 2019

Mohammad Mehralian, Zahra Goodarzvand Chegini and Maryam Khashij

This study aims to activated carbon prepared from pistachio waste by using phosphoric acid as chemical activator agent. Activated carbon adsorbents were prepared from pistachio…

Abstract

Purpose

This study aims to activated carbon prepared from pistachio waste by using phosphoric acid as chemical activator agent. Activated carbon adsorbents were prepared from pistachio waste by using phosphoric acid as chemical activator agent.

Design/methodology/approach

The optimum conditions for the highest adsorption performance were determined by central composite design (CCD). The adsorbent was used for the adsorption of dye reactive black 5 (RB5), and the parameters affecting the adsorption were discussed like pH, initial concentration, contact time and adsorbent dosage. The adsorbent synthesized has been characterized by FTIR spectroscopy and scanning electron microscopy. The kinetic models including pseudo-first-order, pseudo-second-order and intraparticle diffusion with Langmuir and Freundlich isotherm models were applied to investigate the kinetic and isotherms parameters.

Findings

When the dye concentration is 10 mg/L, RB5 dye removal rates reach 87.5 per cent. Moreover, the adsorption process of RB5 follows the pseudo-second-order kinetics and the Freundlich adsorption isotherm.

Practical implications

This study provided a simple and effective way to prepare activated carbon adsorbents from pistachio wastes. This way was conductive to protect environmental from a huge amount of agricultural waste produced and subsequent application for removal of pollutants from aqueous solutions.

Originality/value

The activated carbon adsorbents are prepared via chemical activation, which is prepared with pistachio wastes. There are two main innovations: one is that the novel adsorbents are prepared successfully by waste and the other is that the optimized conditions are designed by CCD.

Details

Pigment & Resin Technology, vol. 49 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 2 October 2019

Yue Li, Xiaoquan Chu, Zetian Fu, Jianying Feng and Weisong Mu

The purpose of this paper is to develop a common remaining shelf life prediction model that is generally applicable for postharvest table grape using an optimized radial basis…

Abstract

Purpose

The purpose of this paper is to develop a common remaining shelf life prediction model that is generally applicable for postharvest table grape using an optimized radial basis function (RBF) neural network to achieve more accurate prediction than the current shelf life (SL) prediction methods.

Design/methodology/approach

First, the final indicators (storage temperature, relative humidity, sensory average score, peel hardness, soluble solids content, weight loss rate, rotting rate, fragmentation rate and color difference) affecting SL were determined by the correlation and significance analysis. Then using the analytic hierarchy process (AHP) to calculate the weight of each indicator and determine the end of SL under different storage conditions. Subsequently, the structure of the RBF network redesigned was 9-11-1. Ultimately, the membership degree of Fuzzy clustering (fuzzy c-means) was adopted to optimize the center and width of the RBF network by using the training data.

Findings

The results show that this method has the highest prediction accuracy compared to the current the kinetic–Arrhenius model, back propagation (BP) network and RBF network. The maximum absolute error is 1.877, the maximum relative error (RE) is 0.184, and the adjusted R2 is 0.911. The prediction accuracy of the kinetic–Arrhenius model is the worst. The RBF network has a better prediction accuracy than the BP network. For robustness, the adjusted R2 are 0.853 and 0.886 of Italian grape and Red Globe grape, respectively, and the fitting degree are the highest among all methods, which proves that the optimized method is applicable for accurate SL prediction of different table grape varieties.

Originality/value

This study not only provides a new way for the prediction of SL of different grape varieties, but also provides a reference for the quality and safety management of table grape during storage. Maybe it has a further research significance for the application of RBF neural network in the SL prediction of other fresh foods.

Details

British Food Journal, vol. 121 no. 11
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 21 December 2020

Mohamed Ibrahim N.H., M. Udayakumar, Sivan Suresh, Suvanjan Bhattacharyya and Mohsen Sharifpur

This study aims to investigate the insights of soot formation such as rate of soot coagulation, rate of soot nucleation, rate of soot surface growth and soot surface oxidation in…

Abstract

Purpose

This study aims to investigate the insights of soot formation such as rate of soot coagulation, rate of soot nucleation, rate of soot surface growth and soot surface oxidation in ethylene/hydrogen/nitrogen diffusion jet flame at standard atmospheric conditions, which is very challenging to capture even with highly sophisticated measuring systems such as Laser Induced Incandescence and Planar laser-induced fluorescence. The study also aims to investigate the volume of soot in the flame using soot volume fraction and to understand the global correlation effect in the formation of soot in ethylene/hydrogen/nitrogen diffusion jet flame.

Design/methodology/approach

A large eddy simulation (LES) was performed using box filtered subgrid-scale tensor. A filtered and residual component of the governing equations such as continuity, momentum, energy and species are resolved and modeled, respectively. All the filtered and residual components are numerically solved using the ILU method by considering PISO pressure–velocity solver. All the hyperbolic flux uses the QUICK algorithm, and an elliptic flux uses SOU to evaluate face values. In all the cases, Courant–Friedrichs–Lewy (CFL) conditions are maintained unity.

Findings

The findings are as follows: soot volume fraction (SVF) as a function of a flame-normalized length for three different Reynolds number configurations (Re = 15,000, Re = 8,000 and Re = 5,000) using LES; soot gas phase and particulate phase insights such as rate of soot nucleation, rate of soot coagulation, rate of soot surface growth and soot surface oxidation for three different Reynolds number configurations (Re = 15,000, Re = 8,000 and Re = 5,000); and soot global correction using total soot volume in the flame volume as a function of Reynolds number and Froude number.

Originality/value

The originality of this study includes the following: coupling LES turbulent model with chemical equilibrium diffusion combustion conjunction with semi-empirical Brookes Moss Hall (BMH) soot model by choosing C6H6 as a soot precursor kinetic pathway; insights of soot formations such as rate of soot nucleation, soot coagulation rate, soot surface growth rate and soot oxidation rate for ethylene/hydrogen/nitrogen co-flow flame; and SVF and its insights study for three inlet fuel port configurations having the three different Reynolds number (Re = 15,000, Re = 8,000 and Re = 5,000).

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 31 no. 7
Type: Research Article
ISSN: 0961-5539

Keywords

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