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Article
Publication date: 8 January 2018

Jin-Li Hu, Ming-Chung Chang and Hui-Wen Tsay

The purpose of this paper is to explore Taiwan’s regional energy efficiency trend and complement the work of the total-factor energy efficiency (TFEE) index proposed by Hu

Abstract

Purpose

The purpose of this paper is to explore Taiwan’s regional energy efficiency trend and complement the work of the total-factor energy efficiency (TFEE) index proposed by Hu and Wang (2006). It further extends panel data stochastic frontier analysis (SFA) modeling for estimating disaggregate energy efficiency.

Design/methodology/approach

This paper applies the panel data stochastic production frontier to estimate the TFEE scores for 20 administrative regions in Taiwan over the period 2004-2015. The SFA models include five inputs (employed population, amount of productive electricity power consumed, amount of electricity consumed for household and non-household electric lighting, amount of gasoline sales, and amount of diesel sales) and one output (total real income in the base year of 2011).

Findings

This research concludes with three main findings: the inefficient administrative regions of Taiwan include mostly large industrial parks and the petrochemical industry cluster; the top five administrative regions with inefficient diesel use are mostly metropolitan areas that the concern of air pollution caused by diesel system arouses the awareness to use less diesel fuel; and the average TFEE score on household and non-household electric lighting is higher than the usage efficiency of productive electricity power, gasoline, and diesel, but there is still room for efficiency improvement.

Originality/value

Most administrative regions in Taiwan are not efficient in almost all kinds of energy use. The results show that the efficiencies of using productive electricity power, gasoline, and diesel need to be improved a lot more.

Details

Management of Environmental Quality: An International Journal, vol. 29 no. 1
Type: Research Article
ISSN: 1477-7835

Keywords

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Book part
Publication date: 20 January 2021

Yao Lixia

Abstract

Details

Energy Security in Times of Economic Transition: Lessons from China
Type: Book
ISBN: 978-1-83982-465-4

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Article
Publication date: 23 April 2020

Duc Hai Nguyen, Hu Wang, Fan Ye and Wei Hu

The purpose of this paper is to investigate the mechanical properties’ behaviors of woven composite cut-out structures with specific parameters. Because of the complexity…

Abstract

Purpose

The purpose of this paper is to investigate the mechanical properties’ behaviors of woven composite cut-out structures with specific parameters. Because of the complexity of micro-scale and meso-scale structure, it is difficult to accurately predict the mechanical material behavior of woven composites. Numerical simulations are increasingly necessary for the design and optimization of test procedures for composite structures made by the woven composite. The results of the proposed method are well satisfied with the results obtained from the experiment and other studies. Moreover, parametric studies on different plates based on the stacking sequences are investigated.

Design/methodology/approach

A multi-scale modeling approach is suggested. Back-propagation neural networks (BPNN), radial basis function (RBF) and least square support vector regression are integrated with efficient global optimization (EGO) to reduce the weight of assigned structure. Optimization results are verified by finite element analysis.

Findings

Compared with other similar studies, the advantage of the suggested strategy uses homogenized properties behaviors with more complex analysis of woven composite structures. According to investigation results, it can be found that 450/−450 ply-orientation is the best buckling load value for all the cut-out shape requirements. According to the optimal results, the BPNN-EGO is the best candidate for the EGO to optimize the woven composite structures.

Originality/value

A multi-scale approach is used to investigate the mechanical properties of a complex woven composite material architecture. Buckling of different cut-out shapes with the same area is surveyed. According to investigation, 45°/−45° ply-orientation is the best for all cut-out shapes. Different surrogate models are integrated in EGO for optimization. The BPNN surrogate model is the best choice for EGO to optimization difficult problems of woven composite materials.

Details

Engineering Computations, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 7 May 2019

Zhaoqiang Wang, Jun Cheng, Hong Ji, Shan Hu and Hao Chen

The purpose of this paper is to study the effects of single parameters for temperature characteristics of oil film in port plate pair and the relationship of calculated…

Abstract

Purpose

The purpose of this paper is to study the effects of single parameters for temperature characteristics of oil film in port plate pair and the relationship of calculated results and experimental results under different viscosity.

Design/methodology/approach

The paper established the mathematical model of oil film of port plate pair, calculated the energy equation of port plate pair, simulated for the oil film and temperature distribution and selected different kinds of lubricants to analyze the calculated value and the experimental value.

Findings

The results show: temperature rise of port plate pair is reduced with the increase of oil viscosity; temperature rise of port plate pair is decreased with rise of initial oil film thickness; temperature rise of port plate pair is increased with the rise of cylinder body speed, inclination angle and sealing belt width; and through the comparison of calculated value and experimental value, under the same viscosity and cylinder speed, experimental results are bigger.

Originality/value

This paper used the methods that the temperature of port plate pair was calculated numerically, and the results were consistent with experimental results, so it can get high precision.

Details

Industrial Lubrication and Tribology, vol. 71 no. 4
Type: Research Article
ISSN: 0036-8792

Keywords

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Article
Publication date: 13 April 2020

Cu Xuan Le and Hu Wang

The purpose of this paper is to examine a proposed model of location-based advertising (LBA) effectiveness upon the influence of integrative perceived values on consumers'…

Abstract

Purpose

The purpose of this paper is to examine a proposed model of location-based advertising (LBA) effectiveness upon the influence of integrative perceived values on consumers' attitude and behavioral responses in the immaturity of LBA in Vietnam.

Design/methodology/approach

A survey research method was utilized to collect data from mobile users. A real sample of 459 respondents was deemed and the Structural Equation Modeling (SEM) was applied to analyze data.

Findings

The results unveil that contextual offers, social facilitation, and advertising values have significantly positive effects on attitude; in turn, attitude mediates between these factors and purchase intention, information seeking and recommendation behaviors. Moreover, social facilitation is a significant stimulator of purchase intention. Otherwise, perceived encroached risk negatively impacts attitude.

Practical implications

Marketers should capture considerable attention to mobile natives' conscious awareness about a mechanism of tailoring their enthusiasm and behavioral responses at the embryonic stage of LBA growth in emerging countries like Vietnam.

Originality/value

This study fills the gap in the current literature by simultaneously exploring the importance of integrative perceived values to construct a hypothetical framework of consumers' responses and performance based on the uses and gratifications theory, inclusive perceived behavioral control derived from theory of planned behavior, associated with contextual value from the nature of LBA.

Details

Asia Pacific Journal of Marketing and Logistics, vol. 33 no. 1
Type: Research Article
ISSN: 1355-5855

Keywords

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Article
Publication date: 31 July 2019

Enying Li, Zheng Zhou, Hu Wang and Kang Cai

This study aims to suggest and develops a global sensitivity analysis-assisted multi-level sequential optimization method for the heat transfer problem.

Abstract

Purpose

This study aims to suggest and develops a global sensitivity analysis-assisted multi-level sequential optimization method for the heat transfer problem.

Design/methodology/approach

Compared with other surrogate-assisted optimization methods, the distinctive characteristic of the suggested method is to decompose the original problem into several layers according to the global sensitivity index. The optimization starts with the several most important design variables by the support vector regression-based efficient global optimization method. Then, when the optimization process progresses, the filtered design variables should be involved in optimization one by one or the setting value. Therefore, in each layer, the design space should be reduced according to the previous optimization result. To improve the accuracy of the global sensitivity index, a novel global sensitivity analysis method based on the variance-based method incorporating a random sampling high-dimensional model representation is introduced.

Findings

The advantage of this method lies in its capability to solve complicated problems with a limited number of sample points. Moreover, to enhance the reliability of optimum, the support vector regression-based global efficient optimization is used to optimize in each layer.

Practical implications

The developed optimization tool is built by MATLAB and can be integrated by commercial software, such as ABAQUS and COMSOL. Lastly, this tool is integrated with COMSOL and applied to the plant-fin heat sink design. Compared with the initial temperature, the temperature after design is over 49°. Moreover, the relationships among all design variables are also disclosed clearly.

Originality/value

The D-MORPH-HDMR is integrated to obtain the coupling relativities among the design variables efficiently. The suggested method can be decomposed into multiplier layers according to the GSI. The SVR-EGO is used to optimize the sub-problem because of its robustness of modeling.

Details

Engineering Computations, vol. 37 no. 2
Type: Research Article
ISSN: 0264-4401

Keywords

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Article
Publication date: 7 August 2017

Enying Li, Fan Ye and Hu Wang

The purpose of study is to overcome the error estimation of standard deviation derived from Expected improvement (EI) criterion. Compared with other popular methods, a…

Abstract

Purpose

The purpose of study is to overcome the error estimation of standard deviation derived from Expected improvement (EI) criterion. Compared with other popular methods, a quantitative model assessment and analysis tool, termed high-dimensional model representation (HDMR), is suggested to be integrated with an EI-assisted sampling strategy.

Design/methodology/approach

To predict standard deviation directly, Kriging is imported. Furthermore, to compensate for the underestimation of error in the Kriging predictor, a Pareto frontier (PF)-EI (PFEI) criterion is also suggested. Compared with other surrogate-assisted optimization methods, the distinctive characteristic of HDMR is to disclose the correlations among component functions. If only low correlation terms are considered, the number of function evaluations for HDMR grows only polynomially with the number of input variables and correlative terms.

Findings

To validate the suggested method, various nonlinear and high-dimensional mathematical functions are tested. The results show the suggested method is potential for solving complicated real engineering problems.

Originality/value

In this study, the authors hope to integrate superiorities of PFEI and HDMR to improve optimization performance.

Details

Engineering Computations, vol. 34 no. 6
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 16 December 2019

Mohammad Zahedul Alam, Wang Hu, Md Rakibul Hoque and Md Abdul Kaium

The purpose of this paper was to explore the comparative influential factors affecting the behavioral intention and actual usage of mHealth services in two distinct…

Abstract

Purpose

The purpose of this paper was to explore the comparative influential factors affecting the behavioral intention and actual usage of mHealth services in two distinct national environments, i.e. China and Bangladesh, in relation to the international expansion of mHealth services.

Design/methodology/approach

In this study, widely accepted Unified Theory of Acceptance and Use of Technology (UTAUT) with two additional variables, i.e. Perceived Reliability and Price Value have been selected as a theoretical framework. Primary data were collected from existing mHealth users among generation Y in both China and Bangladesh. A total of 296 and 250 questionnaires were deemed as usable for data analysis for Bangladesh and China, respectively.

Findings

Performance expectancy and social influence had significant impact on the adoption intention of mHealth services for both countries. Effort expectancy and price value were insignificant factors for Bangladesh, whereas facilitating condition and perceived reliability were insignificant for China.

Practical implications

The insights from this study could benefit mHealth services providers and those policymakers who seek to enter the Chinese and the Bangladeshi healthcare market. The dimensions identified in the study are based on a full assessment of mHealth usages experiences. Global service providers can use the dimensions identified by the paper to better assess their service performance on an international level.

Originality/value

The paper is unique in that it is one of the first cross-country examinations of influential factors affecting the adoption of mHealth services in two different countries. This study confirms the applicability of extended UTAUT model in the context of mHealth services among the generation Y in developing countries such as China and Bangladesh.

Details

International Journal of Pharmaceutical and Healthcare Marketing, vol. 14 no. 1
Type: Research Article
ISSN: 1750-6123

Keywords

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Article
Publication date: 4 April 2016

Liming Chen, Enying Li and Hu Wang

Reflow soldering process is an important step of the surface mount technology. The purpose of this paper is to minimize the maximum warpage of shielding frame by…

Abstract

Purpose

Reflow soldering process is an important step of the surface mount technology. The purpose of this paper is to minimize the maximum warpage of shielding frame by controlling reflow soldering control parameters.

Design/methodology/approach

Compared with other reflow-related design methods, both time and temperate of each extracted time region are considered. Therefore, the number of design variable is increased. To solve the high-dimensional problem, a surrogate-assisted optimization (SAO) called adaptive Kriging high-dimensional representation model (HDMR) is used.

Findings

Therefore, the number of design variable is increased. To solve the high-dimensional problem, a surrogate-assisted optimization (SAO) called HDMR is used. The warpage of shield frame is significantly reduced. Moreover, the correlations of design variables are also disclosed.

Originality/value

Compared with the original Kriging HDMR, the expected improvement (EI) criterion is used and a new projection strategy is suggested to improve the efficiency of optimization method. The application suggests that the adaptive Kriging HDMR has potential capability to solve such complicated engineering problems.

Details

Soldering & Surface Mount Technology, vol. 28 no. 2
Type: Research Article
ISSN: 0954-0911

Keywords

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Article
Publication date: 9 September 2019

Jun Sun, Xiao Zhang, Jianxiong Zhu, Yaming Gao, Hu Wang, Xiaoyong Zhao, Qin Teng, Yanping Ren and Guixiang Zhu

Currently, lubrication analysis of piston ring is generally done under engine rated operating condition. However, the engine (such as the vehicle engine) does not always…

Abstract

Purpose

Currently, lubrication analysis of piston ring is generally done under engine rated operating condition. However, the engine (such as the vehicle engine) does not always operate in rated operating condition, and its operating condition changes frequently in actual use. In addition, the lubrication status of piston ring is generally assumed as the flooded lubrication or a certain form of poor lubrication in most of the lubrication analysis.

Design/methodology/approach

In this paper, based on the equations about the flow rate of lubricating oil and the variation of control volume, the flow model of lubricating oil in the piston ring-cylinder liner conjunction is established. The lubrication analysis of piston ring for a four-stroke engine under different engine operating conditions is done, in which the lubricating oil at the inlet of piston ring is considered as the lubricating oil attached on the relevant location of cylinder wall after the piston ring moves over at the previous stroke.

Findings

There is remarkable difference for the lubrication characteristics of the piston ring under different engine operating conditions. The worst lubrication status of piston ring may not take place under engine rated operating condition.

Originality/value

In this paper, based on the measured engine cylinder pressure, the lubrication analysis of piston ring for a four-stroke engine under different engine operating conditions is done in which the lubricating oil supply condition at the inlet of piston ring is considered. The results of this paper are helpful for the design and research of engine piston ring-cylinder liner conjunction.

Details

Industrial Lubrication and Tribology, vol. 72 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

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