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1 – 10 of 13Gengui Zhou, Hokey Min, Chao Xu and Zhenyu Cao
The purpose of this paper is to develop a benchmark of performance standards for Chinese third‐party logistics providers (3PLs) in the emerging market. It also intends to identify…
Abstract
Purpose
The purpose of this paper is to develop a benchmark of performance standards for Chinese third‐party logistics providers (3PLs) in the emerging market. It also intends to identify various factors that significantly affect the operational efficiency of the Chinese 3PLs and propose ways to improve the competitiveness of 3PLs.
Design/methodology/approach
This paper proposes data envelopment analysis (DEA) to measure the operational efficiency of ten leading 3PLs in China, relative to prior periods and their key competitors. In particular, this paper develops both the Charnes, Cooper and Rhodes model and the Banker, Charnes and Cooper model that are designed to derive weights without being fixed in advance. It also uses step‐wise regression analysis to identify factors influencing the performances of Chinese 3PLs.
Findings
First, the declining efficiency within some Chinese 3PLs coincides with a steep decline in domestic transportation activities due to the SARS outbreak and the slow adaptation of state‐owned enterprise into a more market‐based economy. Second, the sales opportunity and the level of technical expertise are directly correlated with the operational efficiency of 3PLs, whereas the size of 3PLs has no direct bearing on the 3PL's performance. Third, in contrast with the 3PL industry in the USA, the Chinese 3PLs tend to focus on traditional service offerings such as port management, transportation, and warehousing rather than playing the role as the integrator or the lead service provider.
Originality/value
This paper is the first attempt to utilize DEA to develop performance benchmarks for 3PLs in the emerging foreign market. The proposed DEA can be easily modified or extended to similar settings in other Asian countries such as India and East European countries.
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The purpose of this paper is to investigate how R&D originality functions in an open innovation process after the introduction of knowledge spillovers (KSs).
Abstract
Purpose
The purpose of this paper is to investigate how R&D originality functions in an open innovation process after the introduction of knowledge spillovers (KSs).
Design/methodology/approach
To examine the research framework, the authors use hierarchical regression based on questionnaire data from 211 emerging enterprises in China.
Findings
Consistent with the proposed framework, the authors find that the KS effect mediates the positive relationship between openness and innovation performance. In addition, R&D originality weakens the impact of the KS effect on innovation performance.
Research limitations/implications
One limitation is that the questionnaire survey the authors choose for data collection has some natural defects; furthermore, the testing method and research framework need to be improved.
Practical implications
Several implications of the findings for managerial practices are discussed.
Originality/value
First, the research expands the existing theoretical construct by introducing the KS effect into the open innovation process; second, the authors reveal the negative impact of R&D originality on the open innovation process.
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Jia-Nan He, De-wei Yang and Wu Zhenyu
For gravity dams built on foundations with directional joint sets, the seepage in the foundation possesses anisotropic characteristics and may have adverse effects on the…
Abstract
Purpose
For gravity dams built on foundations with directional joint sets, the seepage in the foundation possesses anisotropic characteristics and may have adverse effects on the foundation stability. A methodology for system reliability analysis of gravity dam foundations considering anisotropic seepage and multiple sliding surfaces is proposed in this paper.
Design/methodology/approach
Anisotropic seepages in dam foundations are simulated using finite element method (FEM) with the equivalent continuum model (ECM), and their effect on dam foundation stability is involved by uplift pressures acting on the potential sliding surfaces. The system failure probability of the dam foundation is efficiently estimated using Monte Carlo method (MCM) combined with response surface method (RSM).
Findings
The case study shows that it is necessary to consider the possibly adverse effect of anisotropic seepage on foundation stability of gravity dams and the deterministic analysis of the foundation stability may be misleading. The system reliability analysis of the dam foundation is justified, as the uncertainties in shear strength parameters of the foundation rocks and joint sets as well as aperture, connectivity and spacing of the joint sets are quantified and the system effect of the multiple potential sliding surfaces on the foundation reliability is reasonably considered.
Originality/value
(1) A methodology is proposed for efficient system reliability analysis of foundation stability of gravity dams considering anisotropic seepage and multiple sliding surfaces (2) The influence of anisotropic seepage on the stability of gravity dam foundation is revealed (3) The influence of estimation errors of RSMs on the system reliability assessment of dam foundation is investigated.
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Chuanyuan Zhou, Zhenyu Liu, Chan Qiu and Jianrong Tan
The purpose of this paper is to propose a novel mathematical model to present the three-dimensional tolerance of a discrete surface and to carry out an approach to analyze the…
Abstract
Purpose
The purpose of this paper is to propose a novel mathematical model to present the three-dimensional tolerance of a discrete surface and to carry out an approach to analyze the tolerance of an assembly with a discrete surface structure. A discrete surface is a special structure of a large surface base with several discrete elements mounted on it, one, which is widely used in complex electromechanical products.
Design/methodology/approach
The geometric features of discrete surfaces are separated and characterized by small displacement torsors according to the spatial relationship of discrete elements. The torsor cluster model is established to characterize the integral feature variation of a discrete surface by integrating the torsor model. The influence and accumulation of the assembly tolerance of a discrete surface are determined by statistical tolerance analysis based on the unified Jacobian-Torsor method.
Findings
The effectiveness and superiority of the proposed model in comprehensive tolerance characterization of discrete surfaces are successfully demonstrated by a case study of a phased array antenna. The tolerance is evidently and intuitively computed and expressed based on the torsor cluster model.
Research limitations/implications
The tolerance analysis method proposed requires much time and high computing performance for the calculation of the statistical simulation.
Practical implications
The torsor cluster model achieves the three-dimensional tolerance representation of the discrete surface. The tolerance analysis method based on this model predicts the accumulation of the tolerance of components before their physical assembly.
Originality/value
This paper proposes the torsor cluster as a novel mathematical model to interpret the tolerance of a discrete surface.
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Chuanyuan Zhou, Zhenyu Liu, Chan Qiu and Jianrong Tan
The conventional statistical method of three-dimensional tolerance analysis requires numerous pseudo-random numbers and consumes enormous computations to increase the calculation…
Abstract
Purpose
The conventional statistical method of three-dimensional tolerance analysis requires numerous pseudo-random numbers and consumes enormous computations to increase the calculation accuracy, such as the Monte Carlo simulation. The purpose of this paper is to propose a novel method to overcome the problems.
Design/methodology/approach
With the combination of the quasi-Monte Carlo method and the unified Jacobian-torsor model, this paper proposes a three-dimensional tolerance analysis method based on edge sampling. By setting reasonable evaluation criteria, the sequence numbers representing relatively smaller deviations are excluded and the remaining numbers are selected and kept which represent deviations approximate to and still comply with the tolerance requirements.
Findings
The case study illustrates the effectiveness and superiority of the proposed method in that it can reduce the sample size, diminish the computations, predict wider tolerance ranges and improve the accuracy of three-dimensional tolerance of precision assembly simultaneously.
Research limitations/implications
The proposed method may be applied only when the dimensional and geometric tolerances are interpreted in the three-dimensional tolerance representation model.
Practical implications
The proposed tolerance analysis method can evaluate the impact of manufacturing errors on the product structure quantitatively and provide a theoretical basis for structural design, process planning and manufacture inspection.
Originality/value
The paper is original in proposing edge sampling as a sampling strategy to generating deviation numbers in tolerance analysis.
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Zhiping Hou, Jun Wan, Zhenyu Wang and Changgui Li
In confronting the challenge of climate change and progressing towards dual carbon goals, China is actively implementing low-carbon city pilot policy. This paper aims to focus on…
Abstract
Purpose
In confronting the challenge of climate change and progressing towards dual carbon goals, China is actively implementing low-carbon city pilot policy. This paper aims to focus on the potential impact of this policy on enterprise green governance, aiming to promote the reduction and balance of carbon emissions.
Design/methodology/approach
Based on the panel data of China's large-scale industrial enterprises from 2007 to 2013, this paper uses the Difference-in-differences (DID) method to study the impact and path mechanism of the implementation of low-carbon city pilot policy on enterprise green governance. Heterogeneity analysis is used to compare the effects of low-carbon city pilot policy in different regions, different enterprises and different industries.
Findings
The low-carbon pilot can indeed effectively enhance corporate green governance, a conclusion that still holds after a series of robustness tests. The low-carbon city pilot policy mainly enhances enterprise green governance through two paths: an industrial structure upgrade and enterprise energy consumption, and it improves green governance by reducing enterprise energy consumption through industrial structure upgrade. The impact of low-carbon city pilot policy on enterprise green governance shows significant differences across different regions, different enterprises and different industries.
Research limitations/implications
This paper examines the impact of low-carbon city pilot policy on enterprise green governance. However, due to availability of data, there are still some limitations to be further tackled. The parallel trend test in this paper shows that the pilot policy has a significant positive effect on the green governance of enterprises. However, due to serious lack of data in some years, the authors only selected the enterprise data of a shorter period as our experimental data, which leads the results to still have certain deficiencies. For the verification of the impact mechanism, the conclusions obtained in this paper are relatively limited. Although all the mechanism tests are passed, the reliability of the results still needs to be further tested through future data samples. In addition, as the pilot policy of low-carbon cities is still in progress, the policy can be tracked and analysed in the future as more data are disclosed, and further research can be carried out through dimensional expansion.
Practical implications
Low-carbon city pilot policy plays an important role in inducing the green governance of enterprises. Therefore, policy makers can continue to strengthen the construction of low-carbon city pilots by refining pilot experience, building typical cases, actively promoting pilot policy experience, expanding pilot scope and enhancing the implementation efficiency of pilot policy nationwide, which will contribute to the optimization and upgrading of the regional industrial structure at the urban level and will provide experience and reference for the synergistic implementation plan of pollution reduction and carbon reduction.
Social implications
The impact of the low-carbon city pilot policy on enterprise green governance not only exists in two separate paths of urban industrial upgrading and enterprise energy consumption but also exists in a chain transmission path from macro to micro. The authors find that the effect value of each influence path is different, and there is an obvious leading influence path for the role of enterprise green governance. Therefore, in the process of implementing a low-carbon city pilot policy, policies should be designed specifically for different mechanisms. Moreover, complementing and coordinating several paths should be advocated to give full play to the green governance effect of enterprises brought by different paths and to further expand the scope of industries and enterprises where policies play a role.
Originality/value
To the best of the authors’ knowledge, for the first time, this paper connects macro mechanisms with micro mechanisms, discovering a macro-to-micro transmission mechanism in the process of low-carbon city pilot policy affecting enterprise green governance. That is, the low-carbon city pilot policy can facilitate industrial structure upgrading, resulting in reduced enterprise energy consumption, ultimately enhancing enterprise green governance.
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Gan Zhan, Zhenyu Zhang, Zhihua Chen, Tianzhen Li, Dong Wang, Jigang Zhan and Zhengang Yan
This paper aims to focus on the spatial docking task of unmanned vehicles under ground conditions. The docking task of military unmanned vehicle application scenarios has strict…
Abstract
Purpose
This paper aims to focus on the spatial docking task of unmanned vehicles under ground conditions. The docking task of military unmanned vehicle application scenarios has strict requirements. Therefore, how to design a docking robot mechanism to achieve accurate docking between vehicles has become a challenge.
Design/methodology/approach
In this paper, first, the docking mechanism system is described, and the inverse kinematics model of the docking robot based on Stewart is established. Second, the genetic algorithm-based optimization method for multiobjective parameters of parallel mechanisms including workspace volume and mechanism flexibility is proposed to solve the problem of multiparameter optimization of parallel mechanism and realize the docking of unmanned vehicle space flexibility. The optimization results verify that the structural parameters meet the design requirements. Besides, the static and dynamic finite element analysis are carried out to verify the structural strength and dynamic performance of the docking robot according to the stiffness, strength, dead load and dynamic performance of the docking robot. Finally, taking the docking robot as the experimental platform, experiments are carried out under different working conditions, and the experimental results verify that the docking robot can achieve accurate docking tasks.
Findings
Experiments on the docking robot that the proposed design and optimization method has a good effect on structural strength and control accuracy. The experimental results verify that the docking robot mechanism can achieve accurate docking tasks, which is expected to provide technical guidance and reference for unmanned vehicles docking technology.
Originality/value
This research can provide technical guidance and reference for spatial docking task of unmanned vehicles under the ground conditions. It can also provide ideas for space docking missions, such as space simulator docking.
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The purpose of this paper is to examine the relationship between IPO lockups and founder-CEOs’ compensation and incentives in newly public firms. The paper argues that existence…
Abstract
Purpose
The purpose of this paper is to examine the relationship between IPO lockups and founder-CEOs’ compensation and incentives in newly public firms. The paper argues that existence and length of lockup agreements are affected by bargaining power of founders, which will consequently influence the determination of their compensation contracts.
Design/methodology/approach
Multivariate tests are constructed to examine the relationship between IPO lockups and executive compensation. OLS, fixed-effect panel data model, and the Heckman two-stage model are all utilized to conduct the tests.
Findings
The study finds that lockup existence and lockup length are negatively related to founder-CEOs’ total compensation and positively related to founder-CEOs’ equity incentives. The results hold after controlling for the endogenous decision to sign a lockup agreement at the IPO.
Research limitation/implications
The paper's results suggest that the power of founders and other insiders is a crucial factor in the lockup determination process besides economic factors identified in previous studies. The paper's results also echo the political power theory in the management literature which suggests that an organization's decision making is heavily influenced by relative power of organizational members and reflects their preference.
Originality/value
The paper raises a new explanation for the determinant of IPO lockups that supplements the extant theories. The paper argues that existence and length of lockup agreements could be affected by bargaining power of insiders.
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Feifei Zhong, Guoping Liu, Zhenyu Lu, Lingyan Hu, Yangyang Han, Yusong Xiao and Xinrui Zhang
Robotic arms’ interactions with the external environment are growing more intricate, demanding higher control precision. This study aims to enhance control precision by…
Abstract
Purpose
Robotic arms’ interactions with the external environment are growing more intricate, demanding higher control precision. This study aims to enhance control precision by establishing a dynamic model through the identification of the dynamic parameters of a self-designed robotic arm.
Design/methodology/approach
This study proposes an improved particle swarm optimization (IPSO) method for parameter identification, which comprehensively improves particle initialization diversity, dynamic adjustment of inertia weight, dynamic adjustment of local and global learning factors and global search capabilities. To reduce the number of particles and improve identification accuracy, a step-by-step dynamic parameter identification method was also proposed. Simultaneously, to fully unleash the dynamic characteristics of a robotic arm, and satisfy boundary conditions, a combination of high-order differentiable natural exponential functions and traditional Fourier series is used to develop an excitation trajectory. Finally, an arbitrary verification trajectory was planned using the IPSO to verify the accuracy of the dynamical parameter identification.
Findings
Experiments conducted on a self-designed robotic arm validate the proposed parameter identification method. By comparing it with IPSO1, IPSO2, IPSOd and least-square algorithms using the criteria of torque error and root mean square for each joint, the superiority of the IPSO algorithm in parameter identification becomes evident. In this case, the dynamic parameter results of each link are significantly improved.
Originality/value
A new parameter identification model was proposed and validated. Based on the experimental results, the stability of the identification results was improved, providing more accurate parameter identification for further applications.
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Guodong Sa, Haodong Bai, Zhenyu Liu, Xiaojian Liu and Jianrong Tan
The assembly simulation in tolerance analysis is one of the most important steps for the tolerance design of mechanical products. However, most assembly simulation methods are…
Abstract
Purpose
The assembly simulation in tolerance analysis is one of the most important steps for the tolerance design of mechanical products. However, most assembly simulation methods are based on the rigid body assumption, and those assembly simulation methods considering deformation have a poor efficiency. This paper aims to propose a novel efficient and precise tolerance analysis method based on stable contact to improve the efficiency and reliability of assembly deformation simulation.
Design/methodology/approach
The proposed method comprehensively considers the initial rigid assembly state, the assembly deformation and the stability examination of assembly simulation to improve the reliability of tolerance analysis results. The assembly deformation of mating surfaces was first calculated based on the boundary element method with optimal initial assembly state, then the stability of assembly simulation results was assessed by the density-based spatial clustering of applications with noise algorithm to improve the reliability of tolerance analysis. Finally, combining the small displacement torsor theory, the tolerance scheme was statistically analyzed based on sufficient samples.
Findings
A case study of a guide rail model demonstrated the efficiency and effectiveness of the proposed method.
Research limitations/implications
The present study only considered the form error when generating the skin model shape, and the waviness and the roughness of the matching surface were not considered.
Originality/value
To the best of the authors’ knowledge, the proposed method is original in the assembly simulation considering stable contact, which can effectively ensure the reliability of the assembly simulation while taking into account the computational efficiency.
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