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Article
Publication date: 31 March 2020

Huimin Li, Wenmin Li, Lunyan Wang and Lelin Lv

The Public–Private Partnership (PPP) mode has been widely used in the urban water environment treatment project (UWETP). The public is the direct perceiver of urban water…

Abstract

Purpose

The Public–Private Partnership (PPP) mode has been widely used in the urban water environment treatment project (UWETP). The public is the direct perceiver of urban water environment treatment PPP project (UWETP-PPP), and their satisfaction with it can reflect the project's success to some extent. The purpose of this paper is to provide operational management strategies for special-purpose vehicle (SPV) company through public satisfaction evaluation of UWETP-PPP.

Design/methodology/approach

A questionnaire was designed through the literature review and experts' opinions that consisted of 33 indexes to investigate public satisfaction with UWETP-PPP. Then, the exploratory factor analysis (EFA) was used to confirm the evaluation index system of public satisfaction. Next, the weights of the indexes were calculated by the normalized mean method and fuzzy synthetic evaluation (FSE) was applied to evaluate public satisfaction with UWETP-PPP. Finally, the importance-performance analysis (IPA) was used to suggest improvement strategies of public satisfaction with UWETP-PPP.

Findings

The factors affecting public satisfaction with UWETP-PPP are preliminarily determined, and an evaluation model that provides a specific basis for evaluating public satisfaction with UWETP-PPP in the future is constructed. Furthermore, some strategies and suggestions to improve the performance level of UWETP-PPP are put forward.

Research limitations/implications

First, the factors influencing public satisfaction with UWETP-PPP are numerous and complex. The factors discussed in this study may be further refined to make the research more reliable and effective. Second, the sample from this study can be expanded to multiple projects, so as to make the study more general. Finally, given that the influencing factors in the paper were elicited by using scores obtained through a questionnaire survey, it would bring bias to the result to some extent. The evaluation method can be further improved, such as combining with interval intuitionistic fuzzy evaluation.

Practical implications

In the context of the characteristics of PPP projects in water environment treatment and the huge demand of the country to apply PPP model in the territory of water environment treatment, this study evaluated the public satisfaction with UWETP-PPP in Xuchang City, China. The result provided a beneficial reference for the private organizations to take appropriate actions to improve the public satisfaction level of UWETP-PPP, so as to improve the performance level of SPV. It also provided a system of public satisfaction evaluation with UWETP-PPP, which can be considered as the standard of public satisfaction survey, thus improving the comprehensiveness of the UWETP-PPP performance evaluation system and the government regulatory capacity, thus affecting the sustainable development of UWETP-PPP.

Social implications

In addition, the research results provide a useful reference for the public organizations to issue a UWETP-PPP regulation rule, review a UWETP-PPP design plan, and conduct new similar project decision-making. In summary, the study results not only serve as a good reference for the evaluation of public satisfaction of eco-environmental PPP projects, but also have essential application value for improving the service level, performance improvement and operational management of the SPV.

Originality/value

The research results of this paper have certain wide-spread value, and the research framework and research method can be applied to other infrastructure section, such as transportation, stadium et al.

Details

International Journal of Building Pathology and Adaptation, vol. 39 no. 2
Type: Research Article
ISSN: 2398-4708

Keywords

Article
Publication date: 8 April 2021

Wenmin Chu, Xiang Huang and Shuanggao Li

With the improvement of modern aircraft requirements for safety, long life and economy, higher quality aircraft assembly is needed. However, due to the manufacturing and assembly…

Abstract

Purpose

With the improvement of modern aircraft requirements for safety, long life and economy, higher quality aircraft assembly is needed. However, due to the manufacturing and assembly errors of the posture adjustment mechanism (PAM) used in the digital assembly of aircraft large component (ALC), the posture alignment accuracy of ALC is difficult to be guaranteed, and the posture adjustment stress is easy to be generated. Aiming at these problems, this paper aims to propose a calibration method of redundant actuated parallel mechanism (RAPM) for posture adjustment.

Design/methodology/approach

First, the kinematics model of the PAM is established, and the influence of the coupling relationship between the axes of the numerical control locators (NCL) is analyzed. Second, the calibration method based on force closed-loop feedback is used to calibrate each branch chain (BC) of the PAM, and the solution of kinematic parameters is optimized by Random Sample Consensus (RANSAC). Third, the uncertainty of kinematic calibration is analyzed by Monte Carlo method. Finally, a simulated posture adjustment system was built to calibrate the kinematics parameters of PAM, and the posture adjustment experiment was carried out according to the calibration results.

Findings

The experiment results show that the proposed calibration method can significantly improve the posture adjustment accuracy and greatly reduce the posture adjustment stress.

Originality/value

In this paper, a calibration method based on force feedback is proposed to avoid the deformation of NCL and bracket caused by redundant driving during the calibration process, and RANSAC method is used to reduce the influence of large random error on the calibration accuracy.

Details

Industrial Robot: the international journal of robotics research and application, vol. 48 no. 4
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 19 June 2023

Shuang-Gao Li, Wenmin Chu, Xiang Huang and Jinggang Xu

In the digital assembly system of large aircraft components (LAC), the docking trajectory of LAC is an important factor affecting the docking accuracy and stability of the LAC…

Abstract

Purpose

In the digital assembly system of large aircraft components (LAC), the docking trajectory of LAC is an important factor affecting the docking accuracy and stability of the LAC. The main content of docking trajectory planning is how to move the LAC from the initial posture and position to the target posture and position (TPP). This paper aims to propose a trajectory planning method of LAC based on measured data.

Design/methodology/approach

First, the posture and position error model of the wing is constructed according to the measured data of the measurement points (MPs) and the fork lug joints. Second, the particle swarm optimization algorithm based on the dynamic inertia factor is used to optimize the TPP of the wing. Third, to ensure the efficiency and stability of posture adjustment, the S-shaped curve is used as the motion trajectory of LAC, and the parameters of the trajectory are solved by the generalized multiplier method. Finally, a series of docking experiments are carried out.

Findings

During the process of posture adjustment, the motion of the numerical control locator (NCL) is stable, and the interaction force between the NCLs is always within a reasonable range. After the docking, the MPs are all within the tolerance range, and the coaxiality error of the fork lug hole is less than 0.2 mm.

Originality/value

In this paper, the measured data rather than the theoretical design model is used to solve the TPP, which improves the docking accuracy of LAC. Experiment results show that the proposed trajectory method can complete the LAC docking effectively and improve the docking accuracy.

Details

Robotic Intelligence and Automation, vol. 43 no. 3
Type: Research Article
ISSN: 2754-6969

Keywords

Article
Publication date: 21 April 2020

Wenmin Chu, Xiang Huang and Shuanggao Li

Posture adjustment plays an important role in spacecraft manufacturing. The traditional posture adjustment method, which has a large workload and is difficult to guarantee the…

Abstract

Purpose

Posture adjustment plays an important role in spacecraft manufacturing. The traditional posture adjustment method, which has a large workload and is difficult to guarantee the quality of posture adjustment, cannot meet the requirements of modern spacecraft manufacturing. This paper aims to optimize the trajectory of posture adjustment, reduce the internal force of the posture adjustment mechanism and improve the accuracy of the system.

Design/methodology/approach

First, the measuring point is measured by a laser tracker and the position and posture of the cabin is solved. Then, Newton–Euler method is used to construct the dynamic model of the posture adjustment system (PAS) without internal force. Finally, the adjustment time is optimized based on Fibonacci search method and the trajectory of the cabin is fitted by the fifth order polynomial.

Findings

The simulation results show that, compared with the other trajectory planning methods, this method can effectively avoid the internal force of posture adjustment caused by redundant driving, and the trajectory of velocity and acceleration obtained are continuous, meeting the engineering constraints.

Originality/value

In this paper, a dynamic model of PAS without internal force is constructed. The trajectory planning of posture adjustment based on this model can improve the quality of cabin assembly.

Details

Assembly Automation, vol. 40 no. 3
Type: Research Article
ISSN: 0144-5154

Keywords

Article
Publication date: 27 March 2020

Shuanggao Li, Wenmin Chu and Xiang Huang

The measurement of aircraft barycenter is a verification of theoretical barycenter and is an important step of aircraft development. In the traditional measurement method of…

Abstract

Purpose

The measurement of aircraft barycenter is a verification of theoretical barycenter and is an important step of aircraft development. In the traditional measurement method of aircraft barycenter, the posture of the aircraft needs to be adjusted manually and is measured by optical instruments. The efficiency of posture adjustment depends on the proficiency of workers, and the accuracy of measurement is not high. In view of these problems of the current barycenter measurement method, this paper aims to propose an aircraft barycenter measurement method based on multi-posture.

Design/methodology/approach

In this method, the numerical control locator is used as a supporting part to fix and adjust the aircraft, and the calculation model of aircraft barycenter is established according to the principle of rigid body rotation and the principle of moment balance. Then, the influence of the main error sources on the measurement accuracy of aircraft barycenter is analyzed by Monte Carlo simulation, and the measurement accuracy is compared with that of the barycenter measurement method based on horizontal posture. Finally, the experiment platform of barycenter measurement was built in the laboratory and the experiments were carried out.

Findings

The experimental results show that the barycenter measurement method proposed in this paper has obvious advantages in measurement accuracy and efficiency compared with the traditional method.

Originality/value

This method can be used to measure the barycenter of different types of aircraft quickly and automatically.

Details

Sensor Review, vol. 40 no. 2
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 23 March 2022

Wenmin Chu and Xiang Huang

Large gear components widely exist in the transmission system of helicopters, ships, etc. Due to the small assembly clearance of large gear components, using an automatic docking…

Abstract

Purpose

Large gear components widely exist in the transmission system of helicopters, ships, etc. Due to the small assembly clearance of large gear components, using an automatic docking system based on position control will lead to forced assembly. The purpose of this paper is to reduce the assembly stress of large gear components by an active compliant docking technology based on distributed force sensors.

Design/methodology/approach

Firstly, aiming at the noise interference in three-dimensional force sensor (TDFS), Kalman filter and Savitzky–Golay filter are used to process the sensor’s output signal. Secondly, the active compliant docking control model is constructed according to the principle of impedance control. Thirdly, the contact force is calculated based on the Euler equation, and the impedance control parameters are tuned by the particle swarm optimization algorithm. Finally, an active compliant docking system of a large gear structure based on distributed force sensor is built in the laboratory to verify the proposed method.

Findings

The experimental results show that the contact force and contact torque gradually decrease in all directions and are always in the safe range during the docking process. The feasibility of this method in practical application is preliminarily demonstrated.

Originality/value

The distributed TDFSs are used to replace the traditional six-dimensional force sensor in the active compliant docking system of gear components, which solves the problem of the small bearing capacity of the conventional active compliant docking system. This method can also be used for the docking of other large components.

Details

Sensor Review, vol. 42 no. 3
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 15 February 2022

Yu Zhu, Jun Yang, Hongwei Zhang, Wenmin Zhu, Jie Wang and Zelin Zhou

Marking and inspecting are key steps in hull structure construction. However, currently most marking and inspecting operations are still carried out manually, which leads to low…

Abstract

Purpose

Marking and inspecting are key steps in hull structure construction. However, currently most marking and inspecting operations are still carried out manually, which leads to low assembly efficiency and quality. This paper aims to solve these problems through the application of digital technology: the optical projection and machine vision.

Design/methodology/approach

First, the assembly process model of hull construction is established in 3D design environment. Second, the process information is presented to workers in a virtual form through optical projector, which provides accurate guidance for the manual operation. On this basis, the workers can complete welding and assembly operations readily. Finally, the machine vision method is used to check the assembly results, which can decrease the subjective errors.

Findings

A rapid and accurate assembly positioning for hull structure construction is realized based on optical projection, which can avoid the pollution caused by the marking machine and the error caused by human.

Originality/value

This paper combines the advantages of optical projection and machine vision to the field of shipbuilding. The shortcomings of the traditional marking and inspection methods is effectively solved, which may provide a new way for enhancing the assembly efficiency and quality.

Details

Assembly Automation, vol. 42 no. 2
Type: Research Article
ISSN: 0144-5154

Keywords

Article
Publication date: 29 January 2020

Wenmin Chu and Xiang Huang

Flexible tooling for adjusting the posture of large components of aircraft (LCA) is composed of several numerical control locators (NCLs). Because of the manufacture and…

Abstract

Purpose

Flexible tooling for adjusting the posture of large components of aircraft (LCA) is composed of several numerical control locators (NCLs). Because of the manufacture and installation errors of NCL, the traditional control method of NCL may cause great interaction force between NCLs and form the internal force of LCA during the process of posture adjustment. Aiming at this problem, the purpose of this paper is to propose a control method for posture adjustment system based on hybrid force-position control (HFPC) to reduce the internal force of posture adjustment.

Design/methodology/approach

First of all, the causes of internal force of posture adjustment were analyzed by using homogeneous transformation matrix and inverse kinematics. Then, axles of NCLs were divided into position control axle and force control axle based on the screw theory, and the dynamic characteristics of each axle were simulated by MATLAB. Finally, a simulated posture adjustment system was built in the laboratory to carry out HFPC experiment and was compared with the other two traditional control methods for posture adjustment.

Findings

The experiment results show that HFPC method for redundant actuated parallel mechanism (RAPM) can significantly reduce the interaction force between NCLs.

Originality/value

In this paper, HFPC is applied to the control of the posture adjustment system, which reduces the internal force of LCA and improves the assembly quality of aircraft parts.

Details

Industrial Robot: the international journal of robotics research and application, vol. 47 no. 3
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 14 September 2021

Ncamsile Ashley Nkambule, Wei-Kang Wang, Irene Wei Kiong Ting and Wen-Min Lu

The main purpose of this study is to empirically investigate the impact of intellectual capital efficiency on US multinational software companies' performance from 2012 to 2016 by…

Abstract

Purpose

The main purpose of this study is to empirically investigate the impact of intellectual capital efficiency on US multinational software companies' performance from 2012 to 2016 by applying data envelopment analysis (DEA).

Design/methodology/approach

It adopts a new slacks-based measure (SBM) to obtain a more accurate performance estimation and rank between companies. Regression analysis is used to test the overall IC and each of its elements (Human Capital, Innovation Capital, Process Capital and Customer Capital).

Findings

The univariate result shows that multinational companies are more efficient than non-multinational companies. However, the regression result shows that multinationality can hardly explain the firm efficiency of software firms. Another interesting finding is that intellectual capital has a positive and significant impact on software firm performance in the US human capital influences firm efficiency directly. However, when human capital is combined with the other elements of IC, the contribution of human capital becomes less significant. This is because people may think that innovation capital, process capital and customer capital can replace human capital, but it is not. In short, human capital may affect firm efficiency through other elements of IC (innovation capital, process capital and customer capital) as it is the base of other elements.

Research limitations/implications

The results show that multinational companies have higher efficiency scores than non-multinational companies. In addition, Intellectual capital has a positive and significant impact on software firm performance in the US human capital influences firm efficiency directly. However, when human capital is combined with the other elements of IC, the contribution of human capital becomes less significant. This is because people may think that innovation capital, process capital and customer capital can replace human capital, but it is not. In short, human capital may affect firm efficiency through other elements of IC (innovation capital, process capital and customer capital) as it is the base of other elements.

Practical implications

Overall, the study highlights the needs of having intellectual capital and its elements (Human Capital, Innovation Capital, Process Capital and Customer Capital) to increase firm efficiency.

Originality/value

First, the authors use a more comprehensive elements of IC, which are human capital, innovation capital, process capital and customer capital for a better IC measurement. Second, this study makes the first attempt using the DSBM model via DEA to examine the operating efficiency of US multinational software firms.

Details

Journal of Intellectual Capital, vol. 23 no. 6
Type: Research Article
ISSN: 1469-1930

Keywords

Article
Publication date: 16 October 2018

Xuyue Yin, Xiumin Fan, Wenmin Zhu and Rui Liu

Aiming at presenting an interaction-free assembly assistance tool, the purpose of this paper is to propose a synchronous augmented reality (AR) assembly assistance and monitoring…

Abstract

Purpose

Aiming at presenting an interaction-free assembly assistance tool, the purpose of this paper is to propose a synchronous augmented reality (AR) assembly assistance and monitoring system. The system monitors operator’s hands activity and process completeness to recognize the assembly state, then display the AR contents contextually.

Design/methodology/approach

An assembly behavior recognition method is proposed based on gesture recognition. An assembly completeness inspection method is proposed based on SURF feature matching. Assembly state and AR display state are solved by a novel sequential hybrid AR display control strategy. A synchronous multi-channel AR view output strategy is proposed based on QR matrix decomposition.

Findings

A prototype system has been developed, and case study is performed on an industrial product. Experiments are performed to verify the feasibility, efficiency and recognition accuracy of the proposed methods.

Research limitations/implications

The proposed system assists users to perform assembly tasks with automatic visual guidance and vision monitoring, avoiding distractions caused by redundant human–computer interactions.

Practical implications

All methods are integrated to work on only one head-worn device, making the proposed system portable and cheaper. The vision processing pipelines and the view output channels are reconfigurable for customization.

Originality/value

This paper proposes an interaction-free AR assembly assistance and monitoring system. Assembly behavior recognition and assembly completeness inspection methods are integrated to monitor the assembly state. A sequential hybrid AR display control strategy is proposed to contextually update the AR contents. A synchronous multi-channel AR view output strategy is proposed to fulfill different visualization needs.

Details

Assembly Automation, vol. 39 no. 1
Type: Research Article
ISSN: 0144-5154

Keywords

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