Zhiyuan Liu, Yuwen Chen and Jin Qin
This paper aims to address a pollution-routing problem with one general period of congestion (PRP-1GPC), where the start and finish times of this period can be set freely.
Abstract
Purpose
This paper aims to address a pollution-routing problem with one general period of congestion (PRP-1GPC), where the start and finish times of this period can be set freely.
Design/methodology/approach
In this paper, three sets of decision variables are optimized, namely, travel speeds before and after congestion and departure times on given routes, aiming to minimize total cost including green-house gas emissions, fuel consumption and driver wages. A two-phase algorithm is introduced to solve this problem. First, an adaptive large neighborhood search heuristic is used where new removal and insertion operators are developed. Second, an analysis of optimal speed before congestion is presented, and a tailored speed-and-departure-time optimization algorithm considering congestion is proposed by obtaining the best node to be served first over the congested period.
Findings
The results show that the newly developed operator of congested service-time insertion with noise is generally used more than other insertion operators. Besides, compared to the baseline methods, the proposed algorithm equipped with the new operators provides better solutions in a short time both in PRP-1GPC instances and time-dependent pollution-routing problem instances.
Originality/value
This paper considers a more general situation of the pollution-routing problem that allows drivers to depart before the congestion. The PRP-1GPC is better solved by the proposed algorithm, which adds operators specifically designed from the new perspective of the traveling distance, traveling time and service time during the congestion period.
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This chapter investigates and explores the array of political and social factors which influence the Chinese system of environmental protection, shedding light on the Chinese…
Abstract
Purpose
This chapter investigates and explores the array of political and social factors which influence the Chinese system of environmental protection, shedding light on the Chinese political and juridical process in constructing a stricter and more incisive legal framework.
Methodology/approach
Starting by observing national macroeconomic data, this chapter explores how the Chinese governance system affects the implementation of the legal framework of environmental protection. In addition, it also traces a brief panorama of the most important laws framing environmental protection in China.
Findings
Over the years, the Chinese environmental protection system has been strongly affected by the national multilayered governance system. Nevertheless, the initiative launched by China (more intensively starting from the 11th five-year plan) to build a more virtuous environmental protection system now seems to be returning positive results, in both the renewed legal framework and – even more so – in the attempt (through addressing environmental issues) to reform the entire apparatus of national governance.
Practical implications
The multi-structured national system, which hides conflicting political and economic interests at central and local levels, represents one of the biggest problems for China. This chapter argues that only through a deep reform of the national management scheme can China really guarantee a better future for its environment.
Originality/value
Literature on Chinese environmental protection tends more often to investigate the legal aspect when edifying its environmental legal framework. Very few studies combine economic data and political analysis when studying the Chinese legal framework and its implementation.
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This study attempts to identify the determinant factors for Chinese users’ intention of continuous use of TikTok.
Abstract
Purpose
This study attempts to identify the determinant factors for Chinese users’ intention of continuous use of TikTok.
Design/methodology/approach
Drawing on the theoretical background and previous literature, this study proposes the research model followed by research hypotheses. For the purpose of empirical analysis of this study, we conducted a questionnaire survey on current Chinese TikTok platform users. Factor analysis was conducted to verify the reliability and validity of the measurement variables; Confirmatory factor analysis was conducted to ensure that the structural dimensions of the measurement are effective; the analysis results of the structural equation model for hypothesis test.
Findings
The result of the study indicates that the core service traits (entertainment, informativeness and convenience of use) of TikTok all have a positive effect on user engagement and perceived usefulness. In addition, the study found that both personalized recommendation services and filter bubble, which are features of TikTok's service recommendation system, have a positive effect on user engagement and perceived usefulness of TikTok. In addition, it was found that both user engagement and perceived usefulness have a significant positive effect on continuous use intention. Finally, users’ attitude toward big data indicating privacy concern only had a positive moderating effect on the personalized recommendation service but not on filter bubble.
Originality/value
As consumers’ demand for services tailored to their needs and preferences fast increased, it calls for growing concern over the safety of personal data being used by the platforms. Although this paradox over increased user convenience versus privacy protection issue has been persistently recognized, no previous research empirically addressed this issue in the context of social media platforms.
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Chuanli Qin, Jin Zheng, Jiang Haijian, Tan Qiang and Bai Xuduo
The aim of the paper is to develop a method to block hydroxyl groups of epoxy acrylate (AAEP) in vinyl ester resin (VER) and to study the influence of modified VER on…
Abstract
Purpose
The aim of the paper is to develop a method to block hydroxyl groups of epoxy acrylate (AAEP) in vinyl ester resin (VER) and to study the influence of modified VER on polyurethane/(VER) interpenetrating polymer network (PU/VER IPN).
Design/methodology/approach
The hydroxyl groups of AAEP in VER were blocked via different methods. Infra‐red spectroscopy was adopted to study the influence of the reagents, reaction temperature and feed molar ratio on the blocking effect of hydroxyl groups and the optimised technological parameters were determined. The PU/VER IPN and PU/modified VER IPN were prepared by simultaneous interpenetrating of VER (mixture of AAEP and butyl methacrylate with the mass ratio of 2/1) or modified VER and synthesised PU in their laboratory. The microstructure, dynamic mechanical properties and mechanical properties of PU/VER IPN and PU/modified VER IPN were compared.
Findings
The results showed that compared to unmodified IPN, because the hydroxyl groups in VER were blocked and no chemical cross‐linked structure existed between the two networks, the modified IPN showed dual‐continuous microsturcture with larger phase domain sizes between 20 and 50 nm. The effect damping temperature range of modified IPN was broadened and its damping performance was improved. The mechanical strength of modified IPNs decreased and their break elongation increased evidently.
Practical implications
The PU/modified VER IPN with excellent damping properties can be used in the applications where reduction of vibration and noise is desired.
Originality/value
The PU/modified VER IPN, in which no chemical cross‐linked structure existed between the two networks, was novel and its damping performance was improved and excellent.
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Fanshu Zhao, Jin Cui, Mei Yuan and Juanru Zhao
The purpose of this paper is to present a weakly supervised learning method to perform health evaluation and predict the remaining useful life (RUL) of rolling bearings.
Abstract
Purpose
The purpose of this paper is to present a weakly supervised learning method to perform health evaluation and predict the remaining useful life (RUL) of rolling bearings.
Design/methodology/approach
Based on the principle that bearing health degrades with the increase of service time, a weak label qualitative pairing comparison dataset for bearing health is extracted from the original time series monitoring data of bearing. A bearing health indicator (HI) quantitative evaluation model is obtained by training the delicately designed neural network structure with bearing qualitative comparison data between different health statuses. The remaining useful life is then predicted using the bearing health evaluation model and the degradation tolerance threshold. To validate the feasibility, efficiency and superiority of the proposed method, comparison experiments are designed and carried out on a widely used bearing dataset.
Findings
The method achieves the transformation of bearing health from qualitative comparison to quantitative evaluation via a learning algorithm, which is promising in industrial equipment health evaluation and prediction.
Originality/value
The method achieves the transformation of bearing health from qualitative comparison to quantitative evaluation via a learning algorithm, which is promising in industrial equipment health evaluation and prediction.
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Helena Kantanen and Merja Koskela
The purpose of this chapter is to explore the challenges of health emergency communication as presented in the COVID-19-related research articles in the fields of organisational…
Abstract
The purpose of this chapter is to explore the challenges of health emergency communication as presented in the COVID-19-related research articles in the fields of organisational communication, strategic communication and public relations published between 2020 and mid-2022. A qualitative literature review consisting of two rounds of data selection and ATLAS.ti-assisted content analysis was conducted. The data include 67 articles published in quality journals of communication studies, with a focus on the abstract, results and discussion sections. The findings emphasise the need for emotional support, empathy and both vertical and horizontal informal communication in uncertainty reduction during a major health emergency. The limitations of the study include that the data are limited to the first published journal articles concerning the consequences of COVID-19 and that it comprises publications in communication studies but not related fields, such as health, psychology or management. However, it provides an overview of the research findings and offers guidelines for managers and communication professionals for the development of communication practices under the threat of a major health crisis. Moreover, it proves the importance of healthy and trustful workplace relationships as a prerequisite for coping with uncertainty. All in all, the study provides a good basis for further studies of organisational communication and health emergencies.
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Qin Kang, Yicheng Fan, Kun Zhang, Xiaolang Chen, Hongyu San, Yiqing Chen and Heming Zhao
With excellent mechanic properties and hydrogen embrittlement (HE) resistance, 12Cr2Mo1R(H) steel is suitable to make hot-wall hydrogenation reactors. However, longtime exposure…
Abstract
Purpose
With excellent mechanic properties and hydrogen embrittlement (HE) resistance, 12Cr2Mo1R(H) steel is suitable to make hot-wall hydrogenation reactors. However, longtime exposure to a harsh environment of high-pressure hydrogen at medium temperature in practical application would still induce severe hydrogen uptake and eventually damage the mechanical properties of the steel. The study aims to evaluate the HE resistance of the steel under different tensile strain rates after hydrogen charging and analyze the hydrogen effect from atomic level.
Design/methodology/approach
This research studied the HE properties of 12Cr2Mo1R(H) steel by slow strain rate tests. Meanwhile, the effect of hydrogen on the structures and the mechanical properties of the simplified models of the steel was also investigated by first-principle calculations.
Findings
Experimental results showed that after hydrogen pre-charging in this work, hydrogen had little effect on the microstructure of the steel. The elongations and reduction of cross-sectional area of the samples reduced a lot, by contrast, the yield and tensile strengths changed slightly. The 12Cr2Mo1R(H) steel was not very susceptible to HE with a maximum embrittlement index of about 20.00%. First principles calculation results showed that after H dissolution, lattice distortion occurred and interstitial H atoms would preferentially occupy the tetrahedral interstitial site in bcc-Fe crystal and increase the stability of the supercells. With the increase of H atoms added into the simplified model, the steel still possessed a good ductility and toughness at a low hydrogen concentration, while the material would become brittle as the concentration of hydrogen continued to increase.
Originality/value
These finds can provide valuable information for subsequent HE studies on this steel.
Details
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Yi Bao, Song Cen and Chenfeng Li
A simple shape-free high-order hybrid displacement function element method is presented for precise bending analyses of Mindlin–Reissner plates. Three distortion-resistant and…
Abstract
Purpose
A simple shape-free high-order hybrid displacement function element method is presented for precise bending analyses of Mindlin–Reissner plates. Three distortion-resistant and locking-free eight-node plate elements are proposed by utilizing this method.
Design/methodology/approach
This method is based on the principle of minimum complementary energy, in which the trial functions for resultant fields are derived from two displacement functions, F and f, and satisfy all governing equations. Meanwhile, the element boundary displacements are determined by the locking-free arbitrary order Timoshenko’s beam functions. Then, three locking-free eight-node, 24-DOF quadrilateral plate-bending elements are formulated: HDF-P8-23β for general cases, HDF-P8-SS1 for edge effects along soft simply supported (SS1) boundary and HDF-P8-FREE for edge effects along free boundary.
Findings
The proposed elements can pass all patch tests, exhibit excellent convergence and possess superior precision when compared to all other existing eight-node models, and can still provide good and stable results even when extremely coarse and distorted meshes are used. They can also effectively solve the edge effect by accurately capturing the peak value and the dramatical variations of resultants near the SS1 and free boundaries. The proposed eight-node models possess potential in engineering applications and can be easily integrated into commercial software.
Originality/value
This work presents a new scheme, which can take the advantages of both analytical and discrete methods, to develop high-order mesh distortion-resistant Mindlin–Reissner plate-bending elements.
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Guiwen Liu, Ziyi Qin, Hongjuan Wu, Ling Jia and Jihuan Zhuo
Prefabricated building (PB) has been a pivotal force in advancing global building industrialization and sustainability. However, the PB supply chain operation faces significant…
Abstract
Purpose
Prefabricated building (PB) has been a pivotal force in advancing global building industrialization and sustainability. However, the PB supply chain operation faces significant challenges of exhausting negotiations, poor communication and imperfect information, representing high transaction costs (TCs). Existing literature inadequately addresses governance behaviors to mitigate TCs. This study aims to explore PB supply chain inefficiencies through the lens of TC theory, examining the nuanced relationships between hybrid governance behaviors and TCs and exploring effective governance strategies.
Design/methodology/approach
Based on the theoretical frameworks of governance behavior and TCs, this study employed semi-structured interviews and questionnaire surveys with PB experts in Anhui, China. Subsequently, integrated backpropagation neural network and ordered logistic regression analyses were conducted to identify critical governance behaviors and explore boundaries for TCs reduction.
Findings
TCs of the PB supply chain are elevated (1) from communication and coordination; (2) during the construction and approval stages. Investigation of how governance behaviors influence the TCs indicated that (1) enterprises exert more influence than local governments; (2) governance effectiveness in the transaction and transaction environment dimensions outweighs stakeholder influence and (3) functional TCs exist in PB, associated with component manufacturing, PB contract negotiation and learning cost.
Originality/value
This study extends understanding of TCs in PB by providing nuanced insights into the nature and timing of TCs and elucidates how governance structures shape TCs. Functional TCs intrinsic to PB were identified when exploring the optimization boundaries. These insights equip local governments and enterprises with actionable knowledge to prioritize effective governance behaviors and measures.