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Article
Publication date: 11 June 2024

Xiangbo He, Xiaosheng Liang, Ruirui Li, Kai Zhang, Wenchuan Chen and Yunfeng Peng

This study aims to explore the impact of multisource deformation errors on the oil film contact surface, which arise from manufacturing, assembly, oil pressure and thermal…

62

Abstract

Purpose

This study aims to explore the impact of multisource deformation errors on the oil film contact surface, which arise from manufacturing, assembly, oil pressure and thermal influences, on the motion accuracy of hydrostatic guideway.

Design/methodology/approach

Using thermal-structural coupling simulations, this research investigates the effects of assembly, oil pressure and thermal factors on deformation errors of the oil film contact surface. By integrating these with manufacturing errors, a profile error model for the oil film contact surface is developed, characterizing the cumulative effect of these errors. Using kinematic theory and progressive Mengen flow controller characteristics, the motion error at any position of the hydrostatic guideway is quantified, examining how surface error traits impact motion accuracy.

Findings

The error averaging effect is affected by the profile error of oil film contact surface. Meanwhile, the motion accuracy of hydrostatic guideway is highly sensitive to the oil film contact surface error amplitude.

Originality/value

This approach allows for precise prediction and analysis of motion accuracy in hydrostatic guideways during the design and manufacturing stages. It also provides guidance for planning process tolerances.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-03-2024-0063/

Details

Industrial Lubrication and Tribology, vol. 76 no. 5
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 14 January 2014

Yunfeng Liu, Wenqing Liao, Guangsheng Jin, Quanming Yang and Wei Peng

– The purpose is to realize precise apicoectomy with less surgical risk and improved quality and efficiency.

715

Abstract

Purpose

The purpose is to realize precise apicoectomy with less surgical risk and improved quality and efficiency.

Design/methodology/approach

First, the procedure of precise apicoectomy based on additive manufacturing (AM) and digital design is proposed. With CT images of the patient's oral, a 3D model of alveolar bone and teeth is reconstructed, and based on this model, the infected tissue and enclosed root tip can be determined. Thus, a surgical plan can be created based on clear anatomical relationships and minimal negative constraints, which will then determine the drill position, direction and depth, as well as the resection length of root tip. With this plan, a surgical guide design is performed via a composite model from reversed plaster models and hard tissue models from CT, and accessory tools including drill with stop plane and handle are also selected. With the surgical guide, the virtual plan in the computer can be realized in the clinic.

Findings

With this methodology, the dentist can perform root-end resection with greater accuracy, save more than 30 percent of operatory time, and the discomfort to the patient is reduced to a minimum.

Practical implications

The proposed methodology has been used in ten cases for root-end resections. In fact, this method of designing a computer-based treatment plan with a 3D model of a patient and applying it in the clinic through guiding tools can be used in other surgeries, such as orthognathic surgery or osteotomy.

Originality/value

This case report illustrates that with AM and digital design methods, optimal operational plans can be designed and realized for apicoectomy, and the quality and efficiency of clinical surgery are greatly improved compared with conventional methods.

Details

Rapid Prototyping Journal, vol. 20 no. 1
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 11 December 2024

Hongyue Wu, Yunfeng Chen, Robert F. Cox and Ruoyu Jin

Lack of trust in construction projects will lead to poor project performance or project failure, indicating the importance of trust-building. Existing studies have developed…

34

Abstract

Purpose

Lack of trust in construction projects will lead to poor project performance or project failure, indicating the importance of trust-building. Existing studies have developed various trust models, while most studies covered limited trust factors, failed to clarify their meanings and relationships or lacked qualitative or quantitative evidence. Thus, this study aims to develop a measurement model of trust in construction projects with theoretical justification as well as qualitative and quantitative data.

Design/methodology/approach

A literature review was conducted to identify conceptual types, factors and indicators of trust. Individual interviews and focus groups were performed to test the proposed framework with qualitative data. A survey and confirmatory factor analysis (CFA) method were utilized to build the measurement model of trust using quantitative data in BIM-assisted projects.

Findings

The proposed trust framework covered the four conceptual types, four factors (integrity, competency, benevolence and commitment) and 13 indicators, supported by the results of interviews and focus groups. The measurement model of trust from CFA results supported the significant, positive, and one-to-one relationships between 13 indicators and four factors of trust in BIM-assisted projects.

Originality/value

Theoretically, the study provides new insights into the multi-dimensional nature of trust. In practice, the findings could facilitate trustors and trustees to better understand, build, measure and enhance trust in construction projects.

Details

Engineering, Construction and Architectural Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0969-9988

Keywords

Available. Open Access. Open Access
Article
Publication date: 25 October 2021

Cong Li, YunFeng Xie, Gang Wang, XianFeng Zeng and Hui Jing

This paper studies the lateral stability regulation of intelligent electric vehicle (EV) based on model predictive control (MPC) algorithm.

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Abstract

Purpose

This paper studies the lateral stability regulation of intelligent electric vehicle (EV) based on model predictive control (MPC) algorithm.

Design/methodology/approach

Firstly, the bicycle model is adopted in the system modelling process. To improve the accuracy, the lateral stiffness of front and rear tire is estimated using the real-time yaw rate acceleration and lateral acceleration of the vehicle based on the vehicle dynamics. Then the constraint of input and output in the model predictive controller is designed. Soft constraints on the lateral speed of the vehicle are designed to guarantee the solved persistent feasibility and enforce the vehicle’s sideslip angle within a safety range.

Findings

The simulation results show that the proposed lateral stability controller based on the MPC algorithm can improve the handling and stability performance of the vehicle under complex working conditions.

Originality/value

The MPC schema and the objective function are established. The integrated active front steering/direct yaw moments control strategy is simultaneously adopted in the model. The vehicle’s sideslip angle is chosen as the constraint and is controlled in stable range. The online estimation of tire stiffness is performed. The vehicle’s lateral acceleration and the yaw rate acceleration are modelled into the two-degree-of-freedom equation to solve the tire cornering stiffness in real time. This can ensure the accuracy of model.

Details

Journal of Intelligent and Connected Vehicles, vol. 4 no. 3
Type: Research Article
ISSN: 2399-9802

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Article
Publication date: 16 December 2024

Yunfeng Li, Ruoxuan Li, Ao Tian, Xinming Xu and Hang Zhang

This paper aims to study the influence of different seal structure parameters and working conditions on the air-oil two-phase flow characteristics and leakage characteristics of…

11

Abstract

Purpose

This paper aims to study the influence of different seal structure parameters and working conditions on the air-oil two-phase flow characteristics and leakage characteristics of the seal cavity in the bearing cavity of the aero-engine spindle bearing tester.

Design/methodology/approach

In this paper, the VOF method and RNG k-ε turbulence model are used to explore the flow characteristics and leakage characteristics of the labyrinth seal cavity of an aero-engine spindle bearing tester under the condition of air-oil two-phase flow.

Findings

The distribution of the lubricating oil is related to the sealing clearance and the air-oil ratio. The amount of oil leakage increases with increasing of sealing chamber clearance, air-oil ratio and inlet velocity and decreases with increasing curvature and speed. The amount of air leakage increases with sealing clearance and inlet velocity.

Originality/value

In comparison to the pure air-phase flow field, the air-oil two-phase flow field can more accurately simulate the lubricating oil flow in the sealing chamber.

Details

Multidiscipline Modeling in Materials and Structures, vol. 21 no. 2
Type: Research Article
ISSN: 1573-6105

Keywords

Available. Open Access. Open Access
Article
Publication date: 10 September 2024

Liang Ren, Zerong Zhou, Yaping Fu, Ao Liu and Yunfeng Ma

This study aims to examine the impact of the decision makers’ risk preference on logistics routing problem, contributing to logistics behavior analysis and route integration…

180

Abstract

Purpose

This study aims to examine the impact of the decision makers’ risk preference on logistics routing problem, contributing to logistics behavior analysis and route integration optimization under uncertain environment. Due to the unexpected events and complex environment in modern logistics operations, the logistics process is full of uncertainty. Based on the chance function of satisfying the transportation time and cost requirements, this paper focuses on the fourth party logistics routing integrated optimization problem considering the chance preference of decision makers from the perspective of satisfaction.

Design/methodology/approach

This study used the quantitative method to investigate the relationship between route decision making and human behavior. The cumulative prospect theory is used to describe the loss, gain and utility function based on confidence levels. A mathematical model and an improved ant colony algorithm are employed to solve the problems. Numerical examples show the effectiveness of the proposed model and algorithm.

Findings

The study’s findings reveal that the dual-population improvement strategy enhances the algorithm’s global search capability and the improved algorithm can solve the risk model quickly, verifying the effectiveness of the improvement method. Moreover, the decision-maker is more sensitive to losses, and the utility obtained when considering decision-makers' risk attitudes is greater than that obtained when the decision-maker exhibits risk neutrality.

Practical implications

In an uncertain environment, the logistics decision maker’s risk preference directly affects decision making. Different parameter combinations in the proposed model could be set for decision-makers with different risk attitudes to fit their needs more accurately. This could help managers design effective transportation plans and improve service levels. In addition, the improved algorithm can solve the proposed problem quickly, stably and effectively, so as to help the decision maker to make the logistics path decision quickly according to the required confidence level.

Originality/value

Considering the uncertainty in logistics and the risk behavior of decision makers, this paper studies integrated routing problem from the perspective of opportunity preference. Based on the chance function of satisfying the transportation time and cost requirements, a fourth party logistics routing integrated optimization problem model considering the chance preference of decision makers is established. According to the characteristics of the problem, an improved dual-population ant colony algorithm is designed to solve the proposed model. Numerical examples show the effectiveness the proposed methods.

Details

Modern Supply Chain Research and Applications, vol. 6 no. 4
Type: Research Article
ISSN: 2631-3871

Keywords

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Article
Publication date: 10 August 2022

Weichao Yang, Yikang Liu, E. Deng, Youwu Wang, Xuhui He, Mingfeng Lei and Yunfeng Zou

The purpose of this paper is to understand the natural wind field characteristics of the tunnel entrance section and analyzing the aerodynamic performance of high-speed railway…

285

Abstract

Purpose

The purpose of this paper is to understand the natural wind field characteristics of the tunnel entrance section and analyzing the aerodynamic performance of high-speed railway trains (HSRTs) under natural winds.

Design/methodology/approach

Three typical tunnel entrance section sites, namely, tunnel–bridge in a dry canyon (TBDC), tunnel–bridge in a river canyon (TBRC) and tunnel–flat ground (TF), are selected to conduct a continuous wind field measurement. Based on the measured wind characteristics, the natural winds of the TBDC and TF sites are reconstituted and imported into the two corresponding full-scale computational fluid dynamics models. The aerodynamic loads of the HSRT running on TBDC and TF with reconstituted winds are simply analyzed.

Findings

The von Kármán spectrum can be used to describe the wind field at the tunnel entrance section. In the reconstituted natural wind condition, a time-varying feature of wind speed distribution and leeward side vortex around the HSRT caused by the wind speed fluctuation is found. The fluctuating amplitude of aerodynamic loads at the TBDC infrastructure is up to 97.9% larger than that at the TF infrastructure.

Originality/value

The natural wind characteristics at tunnel entrance sections on the high-speed railway are first measured and analyzed. A numerical reconstitution scheme considering the temporal and spatial variation of natural wind speed is proposed and verified based on field measurement results. The aerodynamic performance of an HSRT under reconstituted natural winds is first investigated.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 33 no. 2
Type: Research Article
ISSN: 0961-5539

Keywords

Available. Open Access. Open Access
Article
Publication date: 26 April 2024

Xue Xin, Yuepeng Jiao, Yunfeng Zhang, Ming Liang and Zhanyong Yao

This study aims to ensure reliable analysis of dynamic responses in asphalt pavement structures. It investigates noise reduction and data mining techniques for pavement dynamic…

203

Abstract

Purpose

This study aims to ensure reliable analysis of dynamic responses in asphalt pavement structures. It investigates noise reduction and data mining techniques for pavement dynamic response signals.

Design/methodology/approach

The paper conducts time-frequency analysis on signals of pavement dynamic response initially. It also uses two common noise reduction methods, namely, low-pass filtering and wavelet decomposition reconstruction, to evaluate their effectiveness in reducing noise in these signals. Furthermore, as these signals are generated in response to vehicle loading, they contain a substantial amount of data and are prone to environmental interference, potentially resulting in outliers. Hence, it becomes crucial to extract dynamic strain response features (e.g. peaks and peak intervals) in real-time and efficiently.

Findings

The study introduces an improved density-based spatial clustering of applications with Noise (DBSCAN) algorithm for identifying outliers in denoised data. The results demonstrate that low-pass filtering is highly effective in reducing noise in pavement dynamic response signals within specified frequency ranges. The improved DBSCAN algorithm effectively identifies outliers in these signals through testing. Furthermore, the peak detection process, using the enhanced findpeaks function, consistently achieves excellent performance in identifying peak values, even when complex multi-axle heavy-duty truck strain signals are present.

Originality/value

The authors identified a suitable frequency domain range for low-pass filtering in asphalt road dynamic response signals, revealing minimal amplitude loss and effective strain information reflection between road layers. Furthermore, the authors introduced the DBSCAN-based anomaly data detection method and enhancements to the Matlab findpeaks function, enabling the detection of anomalies in road sensor data and automated peak identification.

Details

Smart and Resilient Transportation, vol. 6 no. 2
Type: Research Article
ISSN: 2632-0487

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Article
Publication date: 17 October 2008

Yunfeng Zhou and Feng Wan

The purpose of this paper is to present a neural network approach to control performance assessment.

452

Abstract

Purpose

The purpose of this paper is to present a neural network approach to control performance assessment.

Design/methodology/approach

The performance index under study is based on the minimum variance control benchmark, a radial basis function network (RBFN) is used as the pre‐whitening filter to estimate the white noise sequence, and a stable filtering and correlation analysis method is adopted to calculate the performance index by estimating innovations sequence using the RBFN pre‐whitening filter. The new approach is compared with the auto‐regressive moving average model and the Laguerre model methods, for both linear and nonlinear cases.

Findings

Simulation results show that the RBFN approach works satisfactorily for both linear and nonlinear examples. In particular, the proposed scheme shows merits in assessing controller performance for nonlinear systems and surpasses the Laguerre model method in parameter selection.

Originality/value

A RBFN approach is proposed for control performance assessment. This new approach, in comparison with some well‐known methods, provides satisfactory performance and potentials for both linear and nonlinear cases.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 1 no. 4
Type: Research Article
ISSN: 1756-378X

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Article
Publication date: 3 January 2017

Xiaochao Xian, Chenglong Nai, Lixin Li and Shuo Zhao

Immersion is one of the key steps during the preparation of silane-based hybrid films, which has important effects on the performance of films after curing. In this paper, the…

179

Abstract

Purpose

Immersion is one of the key steps during the preparation of silane-based hybrid films, which has important effects on the performance of films after curing. In this paper, the formation process of Zr-doped silane film (i.e. the adsorption of silane and deposition of zirconium compounds) on carbon steel immersed in Zr(NO3)4/silane mixed solutions was investigated.

Design/methodology/approach

The method of in situ monitoring the open circuit potential of a two-electrode system, consisting of carbon steel and saturated calomel electrode, was used. The effects of immersion conditions (i.e. the concentration of Zr(NO3)4 and pH of Zr(NO3)4/silane mixed solution) on the open circuit potential were investigated in detail. Furthermore, the surface coverage rate of different cured films (i.e. Zr cured film, silane cured film and Zr/silane composite cured film) after curing on carbon steel was calculated according to the results of polarization curves. Electrochemical impedance spectroscopy (EIS) was used to study the self-healing property of Zr-doped silane cured film.

Findings

The results indicate that in Zr(NO3)4/silane mixed solutions, most zirconium compounds deposit on the surface of carbon steel at the initial immersing stage, then the adsorption of silane on the residual surface of carbon steel dominates the following immersing stage. EIS results show that the Zr-doped cured film has improved self-healing property.

Originality/value

First, the method of in situ monitoring the open-circuit potential of two-electrode system was applied to investigate the deposition of Zr and the adsorption of silane on carbon steel immersed in Zr(NO3)4/silane mixed solutions. Second, the formation process of Zr-doped silane film was proposed.

Details

Anti-Corrosion Methods and Materials, vol. 64 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

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