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Article
Publication date: 18 June 2024

Wenhuan Ai, Zheng Qing Lei, Li Danyang, Jingming Zeng and Dawei Liu

Highway traffic systems are complex and variable, and studying the bifurcation characteristics of traffic flow systems and designing control schemes for unstable bifurcation…

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Abstract

Purpose

Highway traffic systems are complex and variable, and studying the bifurcation characteristics of traffic flow systems and designing control schemes for unstable bifurcation points can alleviate traffic congestion from a new perspective. Bifurcation analysis is used to explain the changes in system stability, identify the unstable bifurcation points of the system, and design feedback controllers to realize the control of the unstable bifurcation points of the traffic system. It helps to control the sudden changes in the stable behavior of the traffic system and helps to alleviate traffic congestion, which is of great practical significance.

Design/methodology/approach

In this paper, we improve the macroscopic traffic flow model by integrating severe weather factors such as rainfall, snowfall, and dust. We use traveling wave transform to convert it into a traffic flow stability model suitable for branching analysis, thus converting the traffic flow problem into a system stability analysis problem. First, this paper derives the existence conditions of the model Hopf bifurcation and saddle-node bifurcation for the improved macroscopic model, and finds the stability mutation point of the system. Secondly, the connection between the stability mutation points and bifurcation points of the traffic system is analyzed. Finally, for the unstable bifurcation point, a nonlinear system feedback controller is designed using Chebyshev polynomial approximation and stochastic feedback control method.

Findings

The Hopf bifurcation is delayed and completely eliminated without changing the equilibrium point of the system, thus controlling the abrupt behavior of the traffic system.

Originality/value

Currently there are fewer studies to explain the changes in the stability of the transportation system through bifurcation analysis, in this paper; we design a feedback controller for the unstable bifurcation point of the system to realize the control of the transportation system. It is a new research method that helps to control the sudden change of the stable behavior of the traffic system and helps to alleviate traffic congestion, which is of great practical significance.

Details

Engineering Computations, vol. 41 no. 5
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 17 April 2020

Dawei Liu and Sajjad Zeinaly

The creation of partnerships among companies, governments and universities can improve innovation and the technological development of institutions. As innovation is a…

505

Abstract

Purpose

The creation of partnerships among companies, governments and universities can improve innovation and the technological development of institutions. As innovation is a multidimensional concept, more nuanced research is needed to identify, which dimensions of innovation firms should focus on them. This paper aims to investigate the influence of attitude to knowledge sharing (KS) factors, learning organization and creativity on the innovation in marketing biotechnology firms. So, the purpose of this paper is to examine the influence of learning organization, attitude to KS, creativity, information technology (IT) acceptance, KS culture and trust on the innovation by presenting a new framework and a model.

Design/methodology/approach

The structural equation modeling technique is used to examine the reliability and validity of the measurement of the provided model. Data were collected by questionnaires. A case study was carried out in 100 marketing biotechnology firms in the Tehran of Iran. In this paper, smart partial least squares 2.0 was used to evaluate the measurement.

Findings

The result showed that all hypotheses of this research are proved. Also, the results have shown that the attitude to KS, learning organization and creativity affect the innovation in marketing biotechnology firms. As an overall result, the managers should create an enhanced knowledge bank to increase and encourage the KS among employees, thus creating and enhancing innovation in organizations. Also, the results have shown that marketing shortages were mostly connected to access to human resources with related management and marketing experiences and were mainly felt by firms introducing discontinuous novelties.

Research limitations/implications

The main limitation of this paper is that the sample was retrieved from 384 employees in 100 marketing biotechnology institutions. The larger number of samples can yield better results. Next, even though the respondents’ profiles indicated a high probability of them being cognizant of their organization’s efforts in inter-firm KS, learning, creativity and innovation with three or four respondent from each organization answering all questions for such complicated issues always poses the risk of measurement bias and inaccuracy. An ideal situation for future studies would be to pool and compare multiple respondents from the same organization to obtain a more comprehensive firm-level measurement. In addition, this study only surveyed and sampled biotech marketing companies in Iran. Therefore, the model should be examined using samples from other countries because the varieties of culture could have an impact on employee apprehensions. So, future researchers can test the measurement instrument in different countries and/or conduct large multi-national comparisons.

Practical implications

Successful marketing strategies depend very much on an organization’s ability to implement them. This paper provides an excellent study about the future of pharmaceutical KS and shows that innovation paths are linked with local and temporary occasions. Also, the results of this study provide valuable information in formulating marketing biotechnology programs. It is essential to study both economics and innovation for students and academics. The results also suggested that policies to increase economic research will also increase innovation. They could contain the consolidation of the legal framework and institutional resources for public organizations to protect intellectual properties. In general, for successful implementation of strategies an organization has to integrate KS, processes and IT.

Social implications

The paper identifies the most critical factors in the innovation process of enterprizes in marketing biotechnology institutions. The implications derived from this study can shed new light upon policy-making both at the level of governance and in the management practice in Iran’s marketing biotechnology industry. Also, the paper increases understanding of the innovation process in Iran marketing biotechnology companies. This study contributes to innovating management research by offering a set of legal and dependable operational measures. These measures can help academics in theory analysis.

Originality/value

This is the first attempt examining the role of the learning organization, creativity and attitude to KS as a key contingency factor in innovation in Iran marketing biotechnology firms, an issue whose understanding is still developing in the literature. The paper adds to the body of knowledge by allowing better understanding the attitude toward KS and the influence of KS, learning and creativity on innovation. Previous studies did not investigate the KS in marketing biotechnology firms deeply, but, the present paper permits a more complete view on this topic. The guidelines are provided for the top directors to promote KS and innovation according to the research results. From a managerial point of view some critical elements, which are important for the success of KS and application of these elements for progressing institutional guidelines to develop KS, are considered. Theoretical foundations can be extracted from this study, and these foundations can be implemented to investigate connection in KS elements such as feasibilities processes and institution initiative abilities. So, the results could be suitable to managers when arranging an organization and shaping its culture to improve knowledge management.

Details

Kybernetes, vol. 50 no. 5
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 12 November 2013

Yancang Li, Chenguang Ban and Rouya Li

Ant colony algorithm is widely used in recent years as a heuristic algorithm. It provides a new way to solve complicated combinatorial optimization problems. Having been…

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Abstract

Ant colony algorithm is widely used in recent years as a heuristic algorithm. It provides a new way to solve complicated combinatorial optimization problems. Having been enlightened by the behavior of ant colony's searching for food, positive feedback construction and distributed computing combined with certain heuristics are adopted in the algorithm, which makes it easier to find better solution. This paper introduces a series of ant colony algorithm and its improved algorithm of the basic principle, and discusses the ant colony algorithm application situation. Finally, several problems existing in the research and the development prospect of ACO are reviewed.

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World Journal of Engineering, vol. 10 no. 5
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 30 September 2024

Zhanqi Tang, Hongxiang Mu, Yanni He, Dawei Gao and Tianxia Liu

Machinery operating in a sand-dust environment is more susceptible to sand particles. The purpose of this paper is to investigate the impact of sand particle deposition rate…

291

Abstract

Purpose

Machinery operating in a sand-dust environment is more susceptible to sand particles. The purpose of this paper is to investigate the impact of sand particle deposition rate, surface hardness and normal load on the tribological performance.

Design/methodology/approach

A predictive model to approximate the number of sand particles within the pin-on-disc contact surface is proposed. The efficacy of the model is validated through experimental method, which replicates a sand environment with two distinct particle deposition rates. Dry sliding friction experiments are also conducted using 45 carbon steel and H90 brass pins against GCr15 bearing steel discs.

Findings

When at high particle deposition rate [6.89 × 10–5 g/(s·mm2)], the contact surfaces are separated by particles, resulting in an indirect metal contact. While at low deposition rate [6.08 × 10–8 g/(s·mm2)], there is an alternating occurrence of direct and indirect metal contacts. In sand environment, the specific wear rate of 45 and H90 decreases by 50% and 33%, respectively, compared to non-sand environment when the applied load is 2.45 N. However, it is only 0.18% for 45 but remains significant at 25% for H90 at load of 9.8 N.

Originality/value

The predictive model and experimental method used in this paper are helpful for understanding the interaction between particles and sliding surfaces, thereby providing a solid foundation for material selection and load optimization of friction pairs influenced by sand-dust environments.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2024-0155/

Details

Industrial Lubrication and Tribology, vol. 76 no. 10
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 7 October 2014

Dawei Jin, Jianghui Liu, Liuling Liu and Desheng Yin

– The purpose of this paper is to investigate the quality of financial reporting by banks in China, and the profit hiding behavior of banks in particular.

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Abstract

Purpose

The purpose of this paper is to investigate the quality of financial reporting by banks in China, and the profit hiding behavior of banks in particular.

Design/methodology/approach

Reported profit is compared with actual profit using multiple regression analysis. The identification strategy allows the authors to quantify the degree of profit hiding in banking institutions.

Findings

Profit hiding exists in the whole banking sector in China regardless of the ownership structure of individual banks, though joint-stock banks have higher degree of profit hiding. Banks that are more financially constrained hide more profit than those less constrained ones. The competition in the banking industry competition impacts the extent of profit hiding, with higher competition being associated with lower degree of profit hiding.

Research limitations/implications

This paper documents the prevailing behavior of profit hiding in Chinese banks. It raises issues regarding the conventional methods of measuring bank efficiencies using accounting information reported by banking institutions.

Originality/value

This paper empirically examines the profit hiding behavior of banks in a transitional country.

Details

Managerial Finance, vol. 40 no. 10
Type: Research Article
ISSN: 0307-4358

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Article
Publication date: 4 September 2017

Dawei Yi, Zhiyun Zhang, Jin Chen, Libin Niu and Jianhong Peng

The directional solidification Fe-B alloy was prepared. The microstructures and three-body abrasive wear behaviors of directional solidification alloy were investigated.

132

Abstract

Purpose

The directional solidification Fe-B alloy was prepared. The microstructures and three-body abrasive wear behaviors of directional solidification alloy were investigated.

Design/methodology/approach

Fe-B alloy was melted in medium frequency induction furnace. The hardness was measured on HRS-150 Rockwell-hardness tester and HXD-1000TMC tester. The wear characteristic of the alloy was examined with a block-on-ring geometry. The worn surface of the alloy was investigated by scanning electron microscopy and laser scanning microscopy.

Findings

The wear weight loss and worn surface roughness increase with the increasing contact load in wear tests. When the worn surface is perpendicular to the boride growth direction, the highest hardness plane of the boride can resist abrasive effectively under the surrounding and supporting of the martensite matrix.

Originality/value

The relation between boride growth direction and wear direction will cause different boride breaking tendency and wear weight loss.

Details

Industrial Lubrication and Tribology, vol. 69 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Available. Open Access. Open Access
Article
Publication date: 3 June 2022

Shuanbao Yao, Dawei Chen and Sansan Ding

The nose length is the key design parameter affecting the aerodynamic performance of high-speed maglev train, and the horizontal profile has a significant impact on the…

1311

Abstract

Purpose

The nose length is the key design parameter affecting the aerodynamic performance of high-speed maglev train, and the horizontal profile has a significant impact on the aerodynamic lift of the leading and trailing cars Hence, the study analyzes aerodynamic parameters with multi-objective optimization design.

Design/methodology/approach

The nose of normal temperature and normal conduction high-speed maglev train is divided into streamlined part and equipment cabin according to its geometric characteristics. Then the modified vehicle modeling function (VMF) parameterization method and surface discretization method are adopted for the parametric design of the nose. For the 12 key design parameters extracted, combined with computational fluid dynamics (CFD), support vector machine (SVR) model and multi-objective particle swarm optimization (MPSO) algorithm, the multi-objective aerodynamic optimization design of high-speed maglev train nose and the sensitivity analysis of design parameters are carried out with aerodynamic drag coefficient of the whole vehicle and the aerodynamic lift coefficient of the trailing car as the optimization objectives and the aerodynamic lift coefficient of the leading car as the constraint. The engineering improvement and wind tunnel test verification of the optimized shape are done.

Findings

Results show that the parametric design method can use less design parameters to describe the nose shape of high-speed maglev train. The prediction accuracy of the SVR model with the reduced amount of calculation and improved optimization efficiency meets the design requirements.

Originality/value

Compared with the original shape, the aerodynamic drag coefficient of the whole vehicle is reduced by 19.2%, and the aerodynamic lift coefficients of the leading and trailing cars are reduced by 24.8 and 51.3%, respectively, after adopting the optimized shape modified according to engineering design requirements.

Details

Railway Sciences, vol. 1 no. 2
Type: Research Article
ISSN: 2755-0907

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Article
Publication date: 30 April 2019

Yuanjie Zhi, Dongmei Fu, Tao Yang, Dawei Zhang, Xiaogang Li and Zibo Pei

This study aims to achieve long-term prediction on a specific monotonic data series of atmospheric corrosion rate vs time.

273

Abstract

Purpose

This study aims to achieve long-term prediction on a specific monotonic data series of atmospheric corrosion rate vs time.

Design/methodology/approach

This paper presents a new method, used to the collected corrosion data of carbon steel provided by the China Gateway to Corrosion and Protection, that combines non-linear gray Bernoulli model (NGBM(1,1) with genetic algorithm to attain the purpose of this study.

Findings

Results of the experiments showed that the present study’s method is more accurate than other algorithms. In particular, the mean absolute percentage error (MAPE) and the root mean square error (RMSE) of the proposed method in data sets are 9.15 per cent and 1.23 µm/a, respectively. Furthermore, this study illustrates that model parameter can be used to evaluate the similarity of curve tendency between two carbon steel data sets.

Originality/value

Corrosion data are part of a typical small-sample data set, and these also belong to a gray system because corrosion has a clear outcome and an uncertainly occurrence mechanism. In this work, a new gray forecast model was proposed to achieve the goal of long-term prediction of carbon steel in China.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 4
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 6 November 2018

Dawei Lu, Sobhan Asian, Gurdal Ertek and Mete Sevinc

A perception gap refers to the differences in perception among the stakeholders regarding any aspect of the supply chain relationship. The purpose of this paper is to investigate…

1498

Abstract

Purpose

A perception gap refers to the differences in perception among the stakeholders regarding any aspect of the supply chain relationship. The purpose of this paper is to investigate the perception gap among service supply chain partners relating to the relative importance of key performance indicators (KPIs) and the association of this gap with service performance.

Design/methodology/approach

This paper presents an integrative framework that combines statistical methods and data envelopment analysis for computing perception and performance gaps, and for identifying the association between the gaps. The study follows a middle-range theorizing research approach where general inferences are induced from instances, and a theory can be developed from the observation of empirical reality.

Findings

Analysis of data from a leading global insurance service supply chain suggests that perception gap exists and can be recognised as a factor associated with performance gaps. The results suggest that the perception gap not only affects performance but can also be tracked as a meta-KPI to improve performance throughout the service supply chain.

Practical implications

The key implication of the presented research is that service companies can identify and resolve the differences in perceptions regarding the importance of the KPIs, by methodologically computing the gaps and tracking them as meta-KPIs.

Originality/value

The study extends the theoretical boundary of supply chain performance management by introducing the perception and performance gaps as novel meta-KPIs. These meta-KPIs can be computed through the integrative framework developed in the study.

Details

International Journal of Physical Distribution & Logistics Management, vol. 49 no. 1
Type: Research Article
ISSN: 0960-0035

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Article
Publication date: 27 August 2024

Guocheng Lv, Dawei Jia, Changyou Li, Chunyu Zhao, Xiulu Zhang, Feng Yan, Hongzhuang Zhang and Bing Li

This study aims to investigate the effect of countersunk rivet head dimensions on the fatigue performance of the riveted specimens of 2024-T3 alloy.

47

Abstract

Purpose

This study aims to investigate the effect of countersunk rivet head dimensions on the fatigue performance of the riveted specimens of 2024-T3 alloy.

Design/methodology/approach

The relationship between rivet head dimensions and fatigue behavior was investigated by finite element method and fatigue test. The fatigue fracture of the specimens was analyzed by scanning electron microscopy.

Findings

A change of the rivet head dimensions will cause a change in the stress concentration and residual normal stress, the stress concentration near the rivet hole causes the fatigue crack source to be located on the straight section of the countersunk rivet hole and the residual normal stress can effectively restrain the initiation and expansion of fatigue cracks. The fatigue cycle will cause the rivet holes to produce different degrees of surface wear.

Originality/value

The fatigue life of the specimens with the height of the rivet head of 2.28 mm and 2.00 mm are similar, but the specimens with the height of the rivet head of 1.72 mm were far higher than the other specimens.

Details

Aircraft Engineering and Aerospace Technology, vol. 96 no. 9
Type: Research Article
ISSN: 1748-8842

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