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Article
Publication date: 13 July 2021

Hailiang Chen, Chuan Ai, Bin Chen, Yong Zhao, Kaisheng Lai, Lingnan He and Zhihan Liu

The purpose of this paper is to achieve effective governance of online rumors through the proposed rumor propagation model and immunization strategy.

Abstract

Purpose

The purpose of this paper is to achieve effective governance of online rumors through the proposed rumor propagation model and immunization strategy.

Design/methodology/approach

The paper leverages the agent-based modeling (ABM) method to model individuals from two aspects, behavior and attitude. Based on the analysis and research of online data, we propose a rumor propagation model, namely the Untouched view transmit removed-Susceptible hesitate agree disagree (Unite-Shad), and devise an immunization strategy, namely the Gravity Immunization Strategy (GIS). A graph-based framework, namely Pregel, is used to carry out the rumor propagation simulation experiments. Through the experiments, the rationality of the Unite-Shad and the effectiveness of the GIS are verified.

Findings

The study discovers that the inconsistency between human behaviors and attitudes in rumor propagation can be explained by the Unite-shad model. Besides, the GIS, which shows better performance in small-world networks than in scale-free networks, can effectively suppress rumor propagation in the early stage.

Research limitations/implications

This paper provides an effective immunization strategy for rumor governance. Specifically, the Unite-Shad model reveals the mechanism of rumor propagation, and the GIS provides an effective governance method for selecting immune nodes.

Originality/value

The inconsistency of human behaviors and attitudes in real scenes is modeled in the Unite-Shad model. Combined with the model, the definition of diffusion domain is proposed and a novel immunization strategy, namely GIS, is designed, which is significant for the social governance of rumor propagation.

Details

Internet Research, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1066-2243

Keywords

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Article
Publication date: 24 August 2018

Bin Chen, Song Cen, Andrew R. Barron, D.R.J. Owen and Chenfeng Li

The purpose of this paper is to systematically investigate the fluid lag phenomena and its influence in the hydraulic fracturing process, including all stages of fluid-lag…

Abstract

Purpose

The purpose of this paper is to systematically investigate the fluid lag phenomena and its influence in the hydraulic fracturing process, including all stages of fluid-lag evolution, the transition between different stages and their coupling with dynamic fracture propagation under common conditions.

Design/methodology/approach

A plane 2D model is developed to simulate the complex evolution of fluid lag during the propagation of a hydraulic fracture driven by an impressible Newtonian fluid. Based on the finite element method, a fully implicit solution scheme is proposed to solve the strongly coupled rock deformation, fluid flow and fracture propagation. Using the proposed model, comprehensive parametric studies are performed to examine the evolution of fluid lag in various geological and operational conditions.

Findings

The numerical simulations predict that the lag ratio is around 5% or even lower at the beginning stage of hydraulic fracture under practical geological conditions. With the fracture propagation, the lag ratio keeps decreasing and can be ignored in the late stage of hydraulic fracturing for typical parameter combinations. On the numerical aspect, whether the fluid lag can be ignored depends not only on the lag ratio but also on the minimum mesh size used for fluid flow. In addition, an overall mixed-mode fracture propagation factor is proposed to describe the relationship between diverse parameters and fracture curvature.

Research limitations/implications

In this study, relatively simple physical models such as linear elasticity for solid, Newtonian model for fluid and linear elasticity fracture mechanics for fracture are used. The current model does not account for such effects like leak off, poroelasticity and softening of rock formations, which may also visibly affect the fluid lag depending on specific reservoir conditions.

Originality/value

This study helps to understand the effect of fluid lag during hydraulic fracturing processes and provides numerical experience in dealing with the fluid lag with finite element simulation.

Details

Engineering Computations, vol. 35 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

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Article
Publication date: 21 August 2017

Liang Liu, Bin Chen, Wangchun Jiang, Lingnan He and Xiaogang Qiu

WeChat is the largest acquaintance social networking platform in China, in which users can view and reshare web pages shared by friends. This paper aims to analyze the…

Abstract

Purpose

WeChat is the largest acquaintance social networking platform in China, in which users can view and reshare web pages shared by friends. This paper aims to analyze the spatio-temporal dynamics of web pages diffused in WeChat and advice on commercials.

Design/methodology/approach

A large number of web pages diffused in WeChat are collected and exclusively divided into four categories according to their titles, including advertisements, news bulletins, holiday greetings and emotional essays. For each web page, an information cascade (tree structure) is constructed to describe the diffusion trace. Based on the categories, the spatio-temporal popularity is characterized; the topological, temporal and spatial properties are examined; and the spatio-temporal diffusion velocity is explored.

Findings

Through comparative analysis, different categories of pages show diversity. For spatio-temporal popularity, there is no significant difference in cascade size; holiday greetings usually last for a relatively short time on average; emotional essays are more likely to spread to more provinces. For topological, temporal and spatial characteristics, the diffusion process of advertisements is more likely to be broadcasting than other categories; news bulletins and holiday greetings have an obvious bursty; the number of viewing behavior decreases from east to west in general. For spatio-temporal diffusion velocity, emotional essays diffuse the fastest in topological and spatio-temporal dimensions.

Originality/value

These findings contribute to promoting products and providing support for data driven modeling of information diffusion and human activity in spatio-temporal dimensions.

Details

Information Discovery and Delivery, vol. 45 no. 3
Type: Research Article
ISSN: 2398-6247

Keywords

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Article
Publication date: 31 July 2019

Bin Chen, Yibo Zhao and Dong Li

This paper aims to understand the laser–tissue interaction mechanism during ophthalmic laser surgeries through numerical analysis. The influence of laser parameters and…

Abstract

Purpose

This paper aims to understand the laser–tissue interaction mechanism during ophthalmic laser surgeries through numerical analysis. The influence of laser parameters and the multipulse technique were investigated.

Design/methodology/approach

The ocular fundus was simplified as a multilayered homogenous medium model. Afterward, the multilayer Monte Carlo method was used to simulate the propagation and energy deposition of laser light, and a local thermal non-equilibrium two-temperature model was established to simulate the temperature variation of chromophores and surrounding tissue with different laser wavelength.

Findings

Through the model, the selective heating of chromophore (melanin and blood vessels) was clearly illustrated: 1) neglecting the laser energy absorbance by blood in the traditional model will cause significant errors in temperature calculation; 2) the non-thermal equilibrium heat transfer model was needed to obtain an accurate description of the thermal process when the dimensionless pulse width (tp*) is <105. For 532 nm Argon laser, the optimize tp* is around 105 and the appropriate energy density is 5 J/cm2; 3) multipulse technique makes the energy more concentrated within the melanin, thereby reducing the thermal damage in surrounding tissue, with most appropriate pulse number and duty cycle is 10 and 1/10.

Originality/value

Taking the blood absorption into account, the different temperature variations of melanin/vessels and surrounding tissue caused by the selective photo-thermolysis were simulated successfully. By understanding the mechanism of laser therapy, laser parameters and multipulse technique are suggested to improve the clinical results.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 12
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 24 September 2019

Yezhong Fang, Xiaotian Ji, Xingquan Zhang, Jun Wang, Bin Chen, Shiwei Duan, Jinyu Tong, Guangwu Fang and Shanbao Pei

The purpose of this paper is to investigate the dynamic forming process of the micro dent fabricated by laser shock processing on 2024-T3 aluminum alloy. The effect of…

Abstract

Purpose

The purpose of this paper is to investigate the dynamic forming process of the micro dent fabricated by laser shock processing on 2024-T3 aluminum alloy. The effect of laser pluse energy on the deformation of micro dent was also discussed in detail.

Design/methodology/approach

It uses finite element analysis method and the corresponding laser shocking experiment.

Findings

The results demonstrate that the dynamic formation process of micro dent lasts longer in comparison with the shock wave loading time, and the depths of micro dents increase with the increasing laser energy. In addition, laser shocking with higher energy can result in more obvious pileup occurred at the outer edge of micro dent.

Originality/value

Surface micro dents can serve as fluid reservoirs and traps of the wear debris, which can decrease the effects of the wear and friction in rolling and sliding interfaces. The investigations can not only be propitious to comprehensively understand the forming mechanism of laser-shocked dent, but also be beneficial to get sight into the residual stress field induced by laser shocking.

Details

Multidiscipline Modeling in Materials and Structures, vol. 16 no. 1
Type: Research Article
ISSN: 1573-6105

Keywords

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Article
Publication date: 28 April 2020

Jiang-Tao Wang, Shufen Zhang, Chia-Huei Wu, Jian-Jun Yu, Chang-Bin Chen and Sang-Bing Tsai

This study aims to provide a time- and price-sensitive market strategy for merchants to handle the markdown price strategy. The market demand for perishable products is…

Abstract

Purpose

This study aims to provide a time- and price-sensitive market strategy for merchants to handle the markdown price strategy. The market demand for perishable products is usually price – and quality (freshness) – sensitive. The proper handling of markdown-price strategies can help merchants enhance competitiveness and maximize operational performance.

Design/methodology/approach

A markdown strategy consisting of price and markdown time was developed to explore the properties of market strategies based on the dynamic quality evaluation. The strategy considers multiple price discounts and multiple markdown times. The optimal price decisions in each stage and the optimal markdown times were derived during the selling season.

Findings

The results showed the following. A retailer always raises the initial price if it wants to adopt multiple price-markdown strategies. A high initial price may lead to a high inventory at the early stage and bring the next price reduction in advance. Large price discounts can be used to reduce the inventory later. The higher the previous price, the shorter the interval between the next price reduction. The markdown strategies showed that the regular discount as a new business model is not the best pricing model for perishable products. A time- and price-sensitive strategy, however, can increase operational performance and provide new insights for perishable products.

Originality/value

The results showed the following. A retailer always raises the initial price if it wants to adopt multiple price-markdown strategies. A high initial price may lead to a high inventory at the early stage and bring the next price reduction in advance. Large price discounts can be used to reduce the inventory later. The higher the previous price, the shorter the interval between the next price reduction. The markdown strategies showed that the regular discount as a new business model is not the best pricing model for perishable products. A time- and price-sensitive strategy, however, can increase operational performance and provide new insights for perishable products.

Details

Kybernetes, vol. 50 no. 1
Type: Research Article
ISSN: 0368-492X

Keywords

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Article
Publication date: 26 July 2019

Ameen Bin Mohanna and Ali Alqahtany

The purpose of this study is to identify the preferred characteristics of buyers of single-family homes in Saudi Arabia with an emphasis on the city of Dammam.

Abstract

Purpose

The purpose of this study is to identify the preferred characteristics of buyers of single-family homes in Saudi Arabia with an emphasis on the city of Dammam.

Design/methodology/approach

Data were collected using face-to-face structured interviews conducted from November 2016 to May 2017 with 177 owners of single-family homes that were purchased between 2010 and the first quarter of 2017.

Findings

The findings indicate that homes can be divided into three types: villas, detached duplexes and semi-detached duplexes. Also, more than three-quarters of the respondents purchased their homes through mortgages from either lenders or the government. It seems we find that the advantages of the detached duplex, particularly its privacy level, over other types of single-family homes induce homebuyers to choose this home type.

Originality/value

In this study, the authors analyze housing preferences among various segments of the Saudi society, in the city of Dammam, to understand the housing supply in Saudi Arabia. Only a few studies have investigated the preferences of homebuyers in Saudi Arabia. Below the authors provide a literature review, discuss data and methods and results, as well as provide concluding remarks.

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Article
Publication date: 6 February 2017

Daniel Perez Liston

The purpose of this paper is to quantify beta for an online gambling portfolio in the UK and investigates whether it is time-varying. It also examines the dynamic…

Abstract

Purpose

The purpose of this paper is to quantify beta for an online gambling portfolio in the UK and investigates whether it is time-varying. It also examines the dynamic correlations of the online gambling portfolio with both the market and socially responsible portfolios. In addition, this paper documents the effect of important UK gambling legislation on the betas and correlations of the online gambling portfolio.

Design/methodology/approach

This study uses static and time-varying models (e.g. rolling regressions, multivariate GARCH models) to estimate betas and correlations for a portfolio of UK online gambling stocks.

Findings

This study finds that beta for the online gambling portfolio is less than 1, indicative of defensiveness toward the market, a result that is consistent with prior literature for sin stocks. In addition, the conditional correlation between the market and online gambling portfolio is small when compared to the correlation of the market and socially responsible portfolios. Findings suggest that the adoption of the Gambling Act 2005 increases the conditional correlation between the market and online gambling portfolio and it also increases the conditional betas for the online gambling portfolio.

Research limitations/implications

This paper serves as a starting point for future research on online gambling stocks. Going forward, studies can focus on the financial performance or accounting performance of online gambling stocks.

Originality/value

This empirical investigation provides insight into the risk characteristics of publicly listed online gambling companies in the UK.

Details

International Journal of Managerial Finance, vol. 13 no. 1
Type: Research Article
ISSN: 1743-9132

Keywords

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Article
Publication date: 14 June 2011

Duan Chuan‐bin and Chen Peng

The purpose of this paper is to study the relationship of broad‐spectrum analysis and pansystems methodology from the fundamental questions of the study of broad‐spectrum analysis.

Abstract

Purpose

The purpose of this paper is to study the relationship of broad‐spectrum analysis and pansystems methodology from the fundamental questions of the study of broad‐spectrum analysis.

Design/methodology/approach

By means of structure analysis and comparison method, the paper gives an introduction to the inner features and connections of broad‐spectrum analysis and pansystems methodology, respectively.

Findings

The opinion that pansystems methodology applies in the two features of broad‐spectrum analysis is put forward, and three aspects in the application of broad‐spectrum analysis in pansystems methodology are analyzed.

Research limitations/implications

The details of the structural models in this paper have to be worked out.

Practical implications

The paper contributes to understanding the features of broad‐spectrum analysis and pansystems methodology.

Originality/value

The paper reveals the original relationship between broad‐spectrum analysis and pansystems methodology, which embodies the value of pansystems methodology to broad‐spectrum analysis.

Details

Kybernetes, vol. 40 no. 5/6
Type: Research Article
ISSN: 0368-492X

Keywords

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Article
Publication date: 5 May 2015

Guangtao Duan and Bin Chen

The purpose of this paper is to find the best solver for parallelizing particle methods based on solving Pressure Poisson Equation (PPE) by taking Moving Particle…

Abstract

Purpose

The purpose of this paper is to find the best solver for parallelizing particle methods based on solving Pressure Poisson Equation (PPE) by taking Moving Particle Semi-Implicit (MPS) method as an example because the solution for PPE is usually the most time-consuming part difficult to parallelize.

Design/methodology/approach

To find the best solver, the authors compare six Krylov solvers, namely, Conjugate Gradient method (CG), Scaled Conjugate Gradient method (SCG), Bi-Conjugate Gradient Stabilized (BiCGStab) method, Conjugate Gradient Squared (CGS) method with Symmetric Lanczos Algorithm (SLA) method and Incomplete Cholesky Conjugate Gradient method (ICCG) in terms of convergence, time consumption, parallel efficiency and memory consumption for the semi-implicit particle method. The MPS method is parallelized by the hybrid Open Multi-Processing (OpenMP)/Message Passing Interface (MPI) model. The dam-break flow and channel flow simulations are used to evaluate the performance of different solvers.

Findings

It is found that CG converges stably, runs fastest in the serial way, uses the least memory and has highest OpenMP parallel efficiency, but its MPI parallel efficiency is lower than SLA because SLA requires less synchronization than CG.

Originality/value

With all these criteria considered and weighed, the recommended parallel solver for the MPS method is CG.

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