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1 – 10 of 229Liping Wang, Pu Zhang, Pei Zhang, Rongbo Li, Yanke Zhang and Yueqiu Wu
Public–private partnership (PPP) projects are increasingly significant in many countries. The purpose of this paper is to assess the impact of critical success factors (CSFs) on…
Abstract
Purpose
Public–private partnership (PPP) projects are increasingly significant in many countries. The purpose of this paper is to assess the impact of critical success factors (CSFs) on PPP projects and comprehensively consider the interrelations and interaction among dimensions and factors to achieve a better understanding of PPP project management.
Design/methodology/approach
An evaluation index system for PPP projects such as the presented case study is proposed based on a literature review and a survey. Then, interpretative structural modeling is used to transform the CSFs dimension into a multi-level hierarchical model to reflect the driven-dependency relation of each dimension; the fuzzy analytic network process model optimized by moment estimation theory is used to investigate the impact of CSFs by considering their internal impact.
Findings
Regarding the project used as the case study, the driving force and dependence for driving layer and dependent layer are determined. Moreover, in driving layer, efficient and well-structured payment mechanism is the most important CSF if considering the internship and interaction among CSFs, and efficient and well-structured payment mechanism and good governance provide most positive interaction; in dependent layer, population of beneficiaries is the most important CSF if considering the internship and interaction among CSFs, and public client’s satisfaction provides most positive interaction.
Originality/value
This paper developed an evaluation model to explore the interrelationships of dimensions and factors and then determine the impact of CSFs. The model propose in this paper relaxes the independence assumptions of traditional methods and is more in line with reality; besides, weighting method is optimized to obtain more objective and reasonable evaluation results. Through an empirical study, the validity of the model has been verified; therefore, the study can help project stakeholders better understand the CSFs and further improve project performance.
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Yuzhe Liu, Jun Wu, Liping Wang, Jinsong Wang, Dong Wang and Guang Yu
The purpose of this study is to develop a modified parameter identification method and a novel measurement method to calibrate a 3 degrees-of-freedom (3-DOF) parallel tool head…
Abstract
Purpose
The purpose of this study is to develop a modified parameter identification method and a novel measurement method to calibrate a 3 degrees-of-freedom (3-DOF) parallel tool head. This parallel tool head is a parallel mechanism module in a five-axes hybrid machine tool. The proposed parameter identification method is named as the Modified Singular Value Decomposition (MSVD) method. It aims to overcome the difficulty of choosing the algorithm parameter in the regularization identification method. The novel measurement method is named as the vector projection (VP) method which is developed to expand the measurement range of self-made measurement implements.
Design/methodology/approach
Newton Iterative Algorithm based on Least Square Method is analyzed by using the Singular Value Decomposition method. Based on the analysis result, the MSVD method is proposed. The VP method transforms the angle measurement into the displacement measurement by taking full advantage of the ability that the 3-DOF parallel tool head can move in the X – Y plane.
Findings
The kinematic calibration approach is verified by calibration simulations, a Rotation Tool Center Point accuracy test and an experiment of machining an “S”-shaped test specimen.
Originality/value
The kinematic calibration approach with the MSVD method and VP method could be successfully applied to the 3-DOF parallel tool head and other 3-DOF parallel mechanisms.
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Dong Wang, Jun Wu, Liping Wang, Yuzhe Liu and Guang Yu
The purpose of this paper is to describe and evaluate the time-varying and coupling dynamic characteristics of a 3-DOF parallel tool head.
Abstract
Purpose
The purpose of this paper is to describe and evaluate the time-varying and coupling dynamic characteristics of a 3-DOF parallel tool head.
Design/methodology/approach
From the view of control, a new dynamic index of a 3-DOF parallel tool head is proposed based on the dynamic model in the joint space. This index can reflect the time-varying and coupling dynamic characteristics which are the main characteristics of the parallel mechanisms, and its distribution in the whole workspace is also given. Through comparison of the dynamic load (driving current) of each driving shaft, a series of experiments is designed and carried out on a prototype to validate the effectiveness of the dynamic analysis. The tracking error of each driving shaft has also been taken into consideration.
Findings
The simulations of the index have the same variation law with the experimental results. The dynamic load of the driving shaft becomes larger with the increase of the dynamic index, and the dynamic performance becomes worse at the same time.
Originality/value
The main dynamic characteristics of the 3-DOF parallel tool head can be described and evaluated through this work.
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Xingjun Wang, Zhuoran Yang, Feifei Xu and Liping Wang
The microcutting performance of the 10B/Al composite is significantly poor because of the existence of hard boron particles. The effects of cutting parameters, including uncut…
Abstract
Purpose
The microcutting performance of the 10B/Al composite is significantly poor because of the existence of hard boron particles. The effects of cutting parameters, including uncut chip thickness and cutting speed, on the material removal mechanism and surface generation are investigated to improve the surface quality.
Design/methodology/approach
The 2D finite element model, which includes a rigid cutting tool, a reinforced phase, a matrix and a dense layer, is established. The effects of uncut chip thickness on material removal mechanism and surface generation are analyzed from a probabilistic perspective. The relationship between the uncut chip thickness and the probability in which the machined surface will have a better surface quality is constructed. A Gaussian distribution formula is applied to describe the machined surface quality.
Findings
Two representative particle-removal modes, namely, cutting-through and pulling-out modes, are observed. For cutting-through mode, when the relative cutting location is small, better surface quality is obtained. For pulling-out mode, the quality of the machined surface gradually improves because the further increase of the relative cutting location reduces the height of the generated pit and scratches. The microcutting at high cutting speed tends to suppress the scratch phenomenon. The best surface quality will be obtained at small uncut chip thickness and high cutting speed.
Originality/value
The surface quality generated in microcutting of the 10B/Al composite can be improved by optimizing the cutting parameters and controlling the particle-removal modes based on the proposed Gaussian distribution formula.
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XuJin Lang, Liping Wang, Xin Du, Lixia Li and Dongya Zhang
This paper aims to synthesize a novel alkanolamine borate and explore the performance of as a copper wire drawing oil.
Abstract
Purpose
This paper aims to synthesize a novel alkanolamine borate and explore the performance of as a copper wire drawing oil.
Design/methodology/approach
In this paper, a copper wire drawing oil (CU-KL) was formulated by using a novel alkanolamine borate, naphthenic base oil, fatty alcohol polyoxyethylene ether and palm oil. The tribological performance of CU-KL and commercial copper wire drawing oils (CU-DRB and CU-8010) was investigated
Findings
Under applied loads of 5 N-15 N, the average friction coefficient of CU-KL was 29.4%, 5.4% and 25.3% lower than that of CU-DRB, respectively. At sliding speed of 1000–5000 rpm, the average friction coefficient of CU-KL was reduced by 14.3%, 6% and 10.3% compared with CU-DRB, respectively. Through scanning electron microscope and energy dispersive spectrometry, CU-KL can form B-containing compound at the contact interface, which could synergistically enhance the lubrication effect and improve the wear resistance.
Originality/value
The properties of CU-KL under different test condition were studied, and the findings are of great significance for the application of alkanolamine borate in copper wire drawing oil.
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Dongya Zhang, Yanping Gao, Pengju Wu, Yanchao Zhang and Liping Wang
This paper aims to enhance lubrication performance of the pitcher plant–like textured surface with various parameters.
Abstract
Purpose
This paper aims to enhance lubrication performance of the pitcher plant–like textured surface with various parameters.
Design/methodology/approach
A pitcher plant–like structure surface is fabricated on the copper alloy, and the lubrication performance of the pitcher plant–like structure with various parameters is evaluated. In addition, the pressure distribution and oil film load capacity of the pitcher plant–like surface are simulated based on Navier–Stokes equations.
Findings
When the direction of motion aligns with the pitcher plant–like structure, the friction coefficient remains lower than that of the nontextured surface, and it exhibits a decreasing trend with the increasing of the texture width and spacing distance; the lowest friction coefficient (0.04) is achieved with B = 0.3 mm, L = 1.0 mm and θ = 45°, marking a 75% reduction compared to the nontextured surface. Simulation results demonstrate that with the increase in texture width and spacing distance, the oil film load-bearing capacity demonstrates an increasing trend.
Originality/value
Bionic pitcher plants are prepared on the copper alloy to improve the lubrication performance and wear resistance.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2024-0119/
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Saerom Wang, Liping A. Cai and Xinran Lehto
This chapter investigates the antecedents of individuals’ emotional outcomes from their dining-away-from-home experiences and conceptualizes how food and emotions are related and…
Abstract
This chapter investigates the antecedents of individuals’ emotional outcomes from their dining-away-from-home experiences and conceptualizes how food and emotions are related and how travel and emotions are associated. The study applies the stimulus-response theory to set up the premise that emotions that individuals experience while dining out comprise a pivotal part of their emotional well-being and their emotions can be triggered by stimuli encountered on trips and in other away-from-home situations. Cognitive appraisal, arousal, and other causes that are responsible for awakening affective responses are utilized in developing six propositions regarding individuals’ emotional outcomes in travel and dining contexts. Theoretical and practical implications are suggested following the discussions on these propositions.
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Lei Dong, Y. Ken Wang and Kai Du
This study examines whether the source from which nonprofessional investors obtain corporate social responsibility (CSR) disclosure influences their investment-related judgments…
Abstract
This study examines whether the source from which nonprofessional investors obtain corporate social responsibility (CSR) disclosure influences their investment-related judgments and decisions and whether that influence depends on the company's financial performance. In an experiment, we find an asymmetrical effect of information source that varies with financial performance. In particular, information source affects investors' management credibility judgments when the firm announces unfavorable earnings result but not when the announced result is favorable. The mediation analysis reveals that investors' management credibility judgments mediate the joint effect of information source and financial performance on investors' investment decisions. Our findings highlight that the effectiveness of CSR communication can be complicated and that investors are sensitive to other factors that exist in the communication setting, such as the context in which CSR is disclosed (contextual factor) and information source of CSR disclosures (attributional factor).
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