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Open Access
Article
Publication date: 13 November 2018

Bo Liu, Libin Shen, Huanling You, Yan Dong, Jianqiang Li and Yong Li

The influence of road surface temperature (RST) on vehicles is becoming more and more obvious. Accurate predication of RST is distinctly meaningful. At present, however…

Abstract

Purpose

The influence of road surface temperature (RST) on vehicles is becoming more and more obvious. Accurate predication of RST is distinctly meaningful. At present, however, the prediction accuracy of RST is not satisfied with physical methods or statistical learning methods. To find an effective prediction method, this paper selects five representative algorithms to predict the road surface temperature separately.

Design/methodology/approach

Multiple linear regressions, least absolute shrinkage and selection operator, random forest and gradient boosting regression tree (GBRT) and neural network are chosen to be representative predictors.

Findings

The experimental results show that for temperature data set of this experiment, the prediction effect of GBRT in the ensemble algorithm is the best compared with the other four algorithms.

Originality/value

This paper compares different kinds of machine learning algorithms, observes the road surface temperature data from different angles, and finds the most suitable prediction method.

Details

International Journal of Crowd Science, vol. 2 no. 3
Type: Research Article
ISSN: 2398-7294

Keywords

Article
Publication date: 3 August 2021

Yong-Hua Li, Yang Cao, Yong-Xin Wu, Xiao-Ning Bai and Jia-Wei Mao

This paper aims to establish the relationship between crosswind speed and pantograph-catenary lateral deviation, as well as quantify the influence of crosswind speed and…

Abstract

Purpose

This paper aims to establish the relationship between crosswind speed and pantograph-catenary lateral deviation, as well as quantify the influence of crosswind speed and rod size uncertainty on pantograph-catenary contact reliability.

Design/methodology/approach

The closed vector method is used to establish the pantograph-catenary kinematics formula. A new prediction model is proposed by using the bird swarm algorithm to optimize the grey model. The lateral deviation of the pantograph and catenary is predicted via the new model. Then the relationship between the effective length of the rod and operating mileage is inferred by combining the effective length theory with the Gamma process, as well as the pantograph-catenary contact reliability model is established according to reliability theory.

Findings

The results obtained show the impacts of uncertainty design parameters of pantograph rods on pantograph-catenary contact reliability index, and the results at crosswind speed of 0 ms−1 and 5 ms−1 are 5.0630 and 4.1442, respectively. The reliability decreases with the increasing crosswind speed, and can be greater than the reliability calculated for rod size degradation due to long-term use.

Originality/value

Most preceding works on pantograph-catenary contact reliability were based on principles of dynamics, without considering the pantograph-catenary relative motion. This research reveals the law of pantograph-catenary relative motion for uncertainty design parameters and crosswind, and quantifies the reliability from the angle of kinematics.

Details

International Journal of Structural Integrity, vol. 12 no. 4
Type: Research Article
ISSN: 1757-9864

Keywords

Open Access
Article
Publication date: 21 January 2022

Yong Li, Yingchun Zhang, Gongnan Xie and Bengt Ake Sunden

This paper aims to comprehensively clarify the research status of thermal transport of supercritical aviation kerosene, with particular interests in the effect of cracking…

Abstract

Purpose

This paper aims to comprehensively clarify the research status of thermal transport of supercritical aviation kerosene, with particular interests in the effect of cracking on heat transfer.

Design/methodology/approach

A brief review of current research on supercritical aviation kerosene is presented in views of the surrogate model of hydrocarbon fuels, chemical cracking mechanism of hydrocarbon fuels, thermo-physical properties of hydrocarbon fuels, turbulence models, flow characteristics and thermal performances, which indicates that more efforts need to be directed into these topics. Therefore, supercritical thermal transport of n-decane is then computationally investigated in the condition of thermal pyrolysis, while the ASPEN HYSYS gives the properties of n-decane and pyrolysis products. In addition, the one-step chemical cracking mechanism and SST k-ω turbulence model are applied with relatively high precision.

Findings

The existing surrogate models of aviation kerosene are limited to a specific scope of application and their thermo-physical properties deviate from the experimental data. The turbulence models used to implement numerical simulation should be studied to further improve the prediction accuracy. The thermal-induced acceleration is driven by the drastic density change, which is caused by the production of small molecules. The wall temperature of the combustion chamber can be effectively reduced by this behavior, i.e. the phenomenon of heat transfer deterioration can be attenuated or suppressed by thermal pyrolysis.

Originality/value

The issues in numerical studies of supercritical aviation kerosene are clearly revealed, and the conjugation mechanism between thermal pyrolysis and convective heat transfer is initially presented.

Details

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

Keywords

Article
Publication date: 15 July 2019

Yong Li, Yanjun Huang and Xing Xu

Sensorless interior permanent magnet in-wheel motor (IPMIWM), as an exemplar of modular automation system, has attracted considerable interests in recent years. This paper…

113

Abstract

Purpose

Sensorless interior permanent magnet in-wheel motor (IPMIWM), as an exemplar of modular automation system, has attracted considerable interests in recent years. This paper aims to investigate a novel hybrid control approach for the sensorless IPMIWM from a cyber-physical systems (CPS) perspective.

Design/methodology/approach

The control approach is presented based on the hybrid dynamical theory. In the standstill-low (S-L) speed, the rotor position/speed signal is estimated by the method of the high frequency (HF) voltage signal injection. The least square support vector machine (LS-SVM) is used to acquire the rotor position/speed signal in medium-high (M-H) speed operation. Hybrid automata model of the IPMIWM is established due to its hybrid dynamic characteristics in wide speed range. A hybrid state observer (HSO), including a discrete state observer (DSO) and a continuous state observer (CSO), is designed for rotor position/speed estimation of the IPMIWM.

Findings

The hardware-in-the-loop testing based on dSPACE is carried out on the test bench. Experimental investigations demonstrate the hybrid control approach can not only identify the rotor position/speed signal with a certain load but also be able to reject the load disturbance. The reliability and the effectiveness of the proposed hybrid control approach were verified.

Originality/value

The proposed hybrid control approach for the sensorless IPMIWM promotes the deep combination and coordination of sensorless IPMIWM drive system. It also theoretically supports and extends the development of the hybrid control of the highly integrated modular automation system.

Article
Publication date: 19 February 2020

Yu-Ting L.V., Yong Li, De-Xing Yang, Zhenhua Bai, Jinlong Li and Rui Wang

Continuous annealing (CA) units usually lack a physical shapemeter; consequently, real-time display and closed-loop control of the strip shape are impossible to achieve.

Abstract

Purpose

Continuous annealing (CA) units usually lack a physical shapemeter; consequently, real-time display and closed-loop control of the strip shape are impossible to achieve.

Design/methodology/approach

A shape model for the CA process is established in this study. Specifically, a virtual shapemeter and closed-loop control system based on the advanced parameter acquisition system and information transmission of CA units are developed in C++ programming language. This system realises real-time dynamic shape display, closed-loop control and shape prediction by collecting raw data of steel coils and parameters during CA.

Findings

Field test results show that the shape predicted by the virtual shapemeter coincides with the measured shape by over 90 per cent, which fully meets the precision requirement of industrial applications.

Originality/value

Moreover, shape quality is effectively improved without increasing hardware investments.

Details

Engineering Computations, vol. 37 no. 6
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 28 July 2021

Yong-Hai Li, Jin Zheng, Shan-Tao Yue and Zhi-Ping Fan

In recent years, electronic word-of-mouth (e-WOM) concerning travel products reflected in online review information has become an important reference for tourists to make…

Abstract

Purpose

In recent years, electronic word-of-mouth (e-WOM) concerning travel products reflected in online review information has become an important reference for tourists to make their product purchase decisions, while for travel service providers (TSPs), monitoring and improving the e-WOM of their travel products is always an important task. Therefore, based on the online review information, how to capture e-WOM of travel products and find out specific ways to improve the e-WOM is a noteworthy research problem. The purpose of this paper is to develop a method for capturing and analyzing e-WOM toward travel products based on sentiment analysis and stochastic dominance.

Design/methodology/approach

Specifically, online review information of travel products is first crawled and preprocessed. Second, sentiment strengths of online review information toward travel products concerning each feature are judged. Then, the matrix of structured online review information toward travel products is formed. Further, the matrix of e-WOM comparisons between any two travel products is constructed, and e-WOM ranking concerning each travel product is determined. Finally, trade-off chart models are constructed to conduct the e-WOM improvement analyses concerning the travel products.

Findings

An empirical study based on the online review information toward six travel products crawled from the Tuniu.com website is given to illustrate the use of the proposed method.

Originality/value

The proposed method can not only realize the real-time e-WOM monitoring to travel products but also be useful for TSPs to improve the e-WOM of their travel products.

Details

Kybernetes, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 19 August 2021

Yong Li, Feifei Han, Xinzhe Zhang, Kai Peng and Li Dang

In this paper, with the goal of reducing the fuel consumption of UAV, the engine performance optimization is studied and on the basis of aircraft/engine integrated…

Abstract

Purpose

In this paper, with the goal of reducing the fuel consumption of UAV, the engine performance optimization is studied and on the basis of aircraft/engine integrated control, the minimum fuel consumption optimization method of engine given thrust is proposed. In the case of keeping the given thrust of the engine unchanged, the main fuel flow of the engine without being connected to the afterburner is optimally controlled so as to minimize the fuel consumption.

Design/methodology/approach

In this study, the reference model real-time optimization control method is adopted. The engine reference model uses a nonlinear real-time mathematical model of a certain engine component method. The quasi-Newton method is adopted in the optimization algorithm. According to the optimization variable nozzle area, the turbine drop-pressure ratio corresponding to the optimized nozzle area is calculated, which is superimposed with the difference of the drop-pressure ratio of the conventional control plan and output to the conventional nozzle controller of the engine. The nozzle area is controlled by the conventional nozzle controller.

Findings

The engine real-time minimum fuel consumption optimization control method studied in this study can significantly reduce the engine fuel consumption rate under a given thrust. At the work point, this is a low-altitude large Mach work point, which is relatively close to the edge of the flight envelope. Before turning on the optimization controller, the fuel consumption is 0.8124 kg/s. After turning on the optimization controller, you can see that the fuel supply has decreased by about 4%. At this time, the speed of the high-pressure rotor is about 94% and the temperature after the turbine can remain stable all the time.

Practical implications

The optimal control method of minimum fuel consumption for the given thrust of UAV is proposed in this paper and the optimal control is carried out for the nozzle area of the engine. At the same time, a method is proposed to indirectly control the nozzle area by changing the turbine pressure ratio. The relevant UAV and its power plant designers and developers may consider the results of this study to reach a feasible solution to reduce the fuel consumption of UAV.

Originality/value

Fuel consumption optimization can save fuel consumption during aircraft cruising, increase the economy of commercial aircraft and improve the combat radius of military aircraft. With the increasingly wide application of UAVs in military and civilian fields, the demand for energy-saving and emission reduction will promote the UAV industry to improve the awareness of environmental protection and reduce the cost of UAV use and operation.

Details

Aircraft Engineering and Aerospace Technology, vol. 93 no. 7
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 3 July 2020

Yong Li, Gongnan Xie and Bengt Ake Sunden

The purpose of this paper is to numerically study the influence of wall conduction on the heat transfer of supercritical n-decane in the active regenerative cooling channels.

Abstract

Purpose

The purpose of this paper is to numerically study the influence of wall conduction on the heat transfer of supercritical n-decane in the active regenerative cooling channels.

Design/methodology/approach

A horizontally placed rectangular pipe with a solid zone and another one without a solid zone were used. A drastic variation of thermo-physical properties was emphatically addressed. After the verification of mesh and turbulence models comparing with the experimental results, a mesh number of 4.5 M and the low Reynolds number SST k-ω turbulence model were chosen. The solution of the governing equations and the acquisition of the numerical results were executed by the commercial software FLUENT 2020 R1.

Findings

The numerical results indicate that there is a heat transfer deterioration (HTD) potential for the upper wall, lower wall and sidewall with the decrease of mass flux. Due to wall conduction, the distribution of the fluid temperature at spanwise-normal planes becomes uniform and this feature also takes advantage of the relatively uniform transverse velocity. For the streamwise-normal planes, the low fluid temperature appears close to the upper wall at the region near the sidewall and vice versa for the region near the centre. Undoubtedly, the secondary flow at the cross-section plays a crucial role in this process and the relatively cool mainstream is affected by the vortices.

Originality/value

This study warns that the wall conduction must be considered in the practical design and thermal optimization due to the sensibility of thermo-physical properties to the heat flux. The secondary flow caused by the buoyancy force (gravity) plays a significant role in the supercritical heat transfer and mixed convection heat transfer should be further studied.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 31 no. 3
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 5 June 2019

Gangling Hou, Meng Li, Sun Hai, Tianshu Song, Lingshu Wu, Yong Li, Gang Zheng, Feng Shen and Yaodong Chen

Seismic isolation, as an effective risk mitigation strategy of building/bridge structures, is incorporated into AP1000 nuclear power plants (NPPs) to alleviate the seismic…

Abstract

Purpose

Seismic isolation, as an effective risk mitigation strategy of building/bridge structures, is incorporated into AP1000 nuclear power plants (NPPs) to alleviate the seismic damage that may occur to traditional structures of NPPs during their service. This is to promote the passive safety concept in the structural design of AP1000 NPPs against earthquakes.

Design/methodology/approach

In conjunction with seismic isolation, tuned-mass-damping (TMD) is integrated into the seismic resistance system of AP1000 NPPs to satisfy the multi-functional purposes. The proposed base-isolation-tuned-mass-damper (BIS-TMD) is studied by comparing the seismic performance of NPPs with four different design configurations (i.e. without BIS, BIS, BIS-TMD and TMD) with the design parameters of the TMD subsystem optimized.

Findings

Such a new seismic protection system (BIS-TMD) is proved to be promising because the advantages of BIS and TMD can be fully used. The benefits of the new structure include effective energy dissipation (i.e. wide vibration absorption band and a stable damping effect), which results in the high performance of NPPs subject to earthquakes with various intensity levels and spectra features.

Originality/value

Parametric studies are performed to demonstrate the seismic robustness (e.g. consistent performance against the changing mass of the water in the gravity liquid tank and mechanical properties) which further ensures that seismic safety requirements of NPPs can be satisfied through the use of BIS-TMD.

Details

Engineering Computations, vol. 36 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 24 August 2021

Yong-Hua Li, Chi Zhang, Hao Yin, Yang Cao and Xiaoning Bai

This paper proposes an improved fatigue life analysis method for optimal design of electric multiple units (EMU) gear, which aims at defects of traditional Miner fatigue…

77

Abstract

Purpose

This paper proposes an improved fatigue life analysis method for optimal design of electric multiple units (EMU) gear, which aims at defects of traditional Miner fatigue cumulative damage theory.

Design/methodology/approach

A fatigue life analysis method by modifying SN curve and considering material difference is presented, which improves the fatigue life of EMU gear based on shape modification optimization. A corrected method for stress amplitude, average stress and SN curve is proposed, which considers low stress cycle, material difference and other factors. The fatigue life prediction of EMU gear is carried out by corrected SN curve and transient dynamic analysis. Moreover, the gear modification technology combined with intelligent optimization method is adopted to investigate the approach of fatigue life analysis and improvement.

Findings

The results show that it is more corresponded to engineering practice by using the improved fatigue life analysis method than the traditional method. The function of stress and modification amount established by response surface method meets the requirement of precision. The fatigue life of EMU gear based on the intelligent algorithm for seeking the optimal modification amount is significantly improved compared with that before the modification.

Originality/value

The traditional fatigue life analysis method does not consider the influence of working condition and material. The life prediction results by using the method proposed in this paper are more accurate and ensure the safety of the people in the EMU. At the same time, the combination of intelligent algorithm and gear modification can improve the fatigue life of gear on the basis of accurate prediction, which is of great significance to the portability of EMU maintenance.

Details

International Journal of Structural Integrity, vol. 12 no. 5
Type: Research Article
ISSN: 1757-9864

Keywords

1 – 10 of over 1000