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As an advanced manufacturing method, additive manufacturing (AM) technology provides new possibilities for efficient production and design of parts. However, with the continuous expansion of the application of AM materials, subtractive processing has become one of the necessary steps to improve the accuracy and performance of parts. In this paper, the processing process of AM materials is discussed in depth, and the surface integrity problem caused by it is discussed.

Firstly, we listed and analyzed the characterization parameters of metal surface integrity and its influence on the performance of parts and then introduced the application of integrated processing of metal adding and subtracting materials and the influence of different processing forms on the surface integrity of parts. The surface of the trial-cut material is detected and analyzed, and the surface of the integrated processing of adding and subtracting materials is compared with that of the pure processing of reducing materials, so that the corresponding conclusions are obtained.

In this process, we also found some surface integrity problems, such as knife marks, residual stress and thermal effects. These problems may have a potential negative impact on the performance of the final parts. In processing, we can try to use other integrated processing technologies of adding and subtracting materials, try to combine various integrated processing technologies of adding and subtracting materials, or consider exploring more efficient AM technology to improve processing efficiency. We can also consider adopting production process optimization measures to reduce the processing cost of adding and subtracting materials.

With the gradual improvement of the requirements for the surface quality of parts in the production process and the in-depth implementation of sustainable manufacturing, the demand for integrated processing of metal addition and subtraction materials is likely to continue to grow in the future. By deeply understanding and studying the problems of material reduction and surface integrity of AM materials, we can better meet the challenges in the manufacturing process and improve the quality and performance of parts. This research is very important for promoting the development of manufacturing technology and achieving success in practical application.

With numerous and ambiguous sets of information and often conflicting requirements, construction management is a complex process involving much uncertainty. Decision makers may be challenged with satisfying multiple criteria using vague information. Fuzzy multi-criteria decision-making (FMCDM) provides an innovative approach for addressing complex problems featuring diverse decision makers’ interests, conflicting objectives and numerous but uncertain bits of information. FMCDM has therefore been widely applied in construction management. With the increase in information complexity, extensions of fuzzy set (FS) theory have been generated and adopted to improve its capacity to address this complexity. Examples include hesitant FSs (HFSs), intuitionistic FSs (IFSs) and type-2 FSs (T2FSs). This chapter introduces commonly used FMCDM methods, examines their applications in construction management and discusses trends in future research and application. The chapter first introduces the MCDM process as well as FS theory and its three main extensions, namely, HFSs, IFSs and T2FSs. The chapter then explores the linkage between FS theory and its extensions and MCDM approaches. In total, 17 FMCDM methods are reviewed and two FMCDM methods (i.e. T2FS-TOPSIS and T2FS-PROMETHEE) are further improved based on the literature. These 19 FMCDM methods with their corresponding applications in construction management are discussed in a systematic manner. This review and development of FS theory and its extensions should help both researchers and practitioners better understand and handle information uncertainty in complex decision problems.

Previous literature suggests that people might purchase symbolic products to signal their social identity. However, in the organizational context, subordinates as customers might choose products with less brand prestige than what they want and can afford, just to make sure their choices are below the invisible “red-line” set by the brands of their supervisors. The authors term the phenomenon as “boss ceiling effect,” and term the behavior that people often downgrade their original choice to make sure the brand prestige is lower than that of the product owned by their boss as “downgrading behavior,” which have not been explored and well explained by existing literature so far. The paper aims to discuss this issue.

The authors conduct qualitative study to explore the existence of boss ceiling effect and providing possible influential factors of brand downgrading attitude. The quantitative study empirically examines the relationships among undesired self, perceived risk, organizational culture balance, and downgrading attitude and intension.

The authors find that undesired self-congruence and perceived risk are positively related to the downgrading attitude. In addition, the culture balance directly affects the brand downgrading attitude negatively and also moderates the relationship between undesired self-congruence and downgrading attitude positively and the relationship between perceived risk and downgrading attitude negatively.

The authors contribute to both organizational culture research and symbolic consumption research by considering symbolic consumption behavior in organization context. It is of great practical implications for marketers of symbolic consumption to understand the downgrading behavior.

The purpose of this study is to simulate the temperature distribution during an electron beam freeform fabrication (EBF³) process based on a fully threaded tree (FTT) technique in various scales and to analyze the temperature variation with time in different regions of the part.

This study presented a revised model for the temperature simulation in the EBF³ process. The FTT technique was then adopted as an adaptive grid strategy in the simulation. Based on the simulation results, an analysis regarding the temperature distribution of a circular deposit and substrate was performed.

The FTT technique was successfully adopted in the simulation of the temperature field during the EBF³ process. The temperature bands and oscillating temperature curves appeared in the deposit and substrate.

The FTT technique was introduced into the numerical simulation of an additive manufacturing process. The efficiency of the process was improved, and the FTT technique was convenient for the 3D simulations and multi-pass deposits.

As a strand in industrialization movement in architecture, engineering and construction (AEC) industry, prefabricated construction (PC) has gained widespread popularity due to high efficiency, energy saving, low environmental impacts, safety and other advantages of PC. Well-managed supply chain can further leverage the advantages of PC. However, there is a lack of more systematically overview of the prefabricated construction supply chain (PCSC). This paper aims to comb the current status and look into the future direction of PCSC by reviewing the existing research.

In total, 131 articles related to prefabricated construction supply chain management (PCSCM) from 2000 to 2022 have been collated to (1) conduct a bibliometric analysis by using VOSviewer, including the literature sources, keywords co-occurrence, co-authorships, authorship citation and country active in the field of PCSCM; (2) classify and summarize the status of research in PCSCM through qualitative discussion and (3) point out the future research directions.

In total, 131 articles are carried out for bibliometric analysis and in-depth qualitative discussion, the visualization maps and the main research themes in the field of PCSCM are obtained. The results show that supply chain intelligentization and informatization are hot topics. Finally, future research directions that should be paid attention to in the field of PCSCM are pointed out.

This study can help project managers understand the current status and problems of PCSC operations and provide a basis for future management decisions.

Compared with previous studies, this study adds the dimension of “article authorship” to the quantitative analysis and discusses the research themes in the field of PCSCM in a comprehensive manner. In addition, this paper deeply discusses the main research topics from both the specific contents and research methods adopted.

Demands for Industrialized Construction (IC) have intensified with growing construction industry imperatives to (A) boost performance; (B) reduce reliance on “in-situ and on-site” operations; and (C) strengthen supply chain resilience (SCR) not just for survival but also to fulfill obligations to clients in the coronavirus disease 2019–induced (COVID-19–induced) “new normal”. In addressing these imperatives, this paper targets more effective leveraging of latent efficiencies of off-site-manufacture, based on findings from a Hong Kong (HK)–based study on assessing and improving SCR in IC in a high-density city.

Starting with the identification of critical supply chain vulnerabilities (CSCVs), this study developed a multilevel–multicriteria mathematical model to evaluate the vulnerability levels of IC supply chains (SCs) in HK based on an in-depth questionnaire survey followed by experts' inputs and analyzing them using fuzzy synthetic evaluation (FSE).

The overall vulnerability index indicates that IC in HK is substantially vulnerable to disruptions, while production-based vulnerabilities have the highest impact. Top management attention is needed to address these CSCVs in IC in HK.

To the authors' knowledge, this is the first structured evaluation model that measures the vulnerability level of IC, providing useful insights to industry stakeholders for well-informed decision-making in achieving resilient, sustainable and performance-enhanced SCs.

The geological conditions of Longyang Reservoir are complex and it is located in strong earthquake area. In order to determine its seismic characteristics, the seismic response and residual deformation of embankment dam should be studied to provide calculation basis for dam design and construction.

Based on the geological survey data of Longyang Reservoir, the dam filling materials are tested by dynamic deformation tests, and the equivalent linear constitutive model parameters of the filling materials are obtained. Based on Duncan-Chang E-B model, the stress state of embankment dam in Longyang Reservoir before earthquake is calculated, and the dynamic response and earthquake residual deformation of embankment dam in Longyang Reservoir under earthquake condition are calculated by using equivalent linear model and Shen Zhu-jiang’s residual deformation model.

The results show that with the increase of dynamic shear strain, the dynamic shear modulus decreases and the damping ratio increases. The scatter plot between dynamic shear modulus and dynamic shear strain, and the scatter plot between damping ratio and dynamic shear strain under different confining pressures show strips. The calculation results shows that the acceleration of embankment dam in Longyang Reservoir increases with the increase of dam height, and the acceleration distribution has obvious amplification effect. Combined with the maximum dynamic shear strain during the earthquake and the state before the earthquake, the maximum vertical residual deformation of embankment dam in Longyang Reservoir is 2.98 cm which occurs at the top of the dam, calculated by the Shen Zhu-jiang’s residual deformation model.

Finite element calculation model parameters of embankment dam are obtained by dynamic triaxial tests. Seismic dynamic responses and residual deformation of embankment dam are analyzed. With the increase of dam height, the acceleration distribution shows an obvious amplification effect. The vertical displacement of embankment dam is larger along the dam axis and decreases in the upstream and downstream direction. The maximum horizontal displacement of embankment dam occurs in the middle of upstream and downstream dam slopes.

• (1)

  Finite element calculation model parameters of embankment dam are obtained by dynamic triaxial tests.

• (2)

  Seismic dynamic responses and residual deformation of embankment dam are analyzed.

• (3)

  With the increase of dam height, the acceleration distribution shows an obvious amplification effect.

• (4)

  The vertical displacement of embankment dam is larger along the dam axis and decreases in the upstream and downstream direction.

• (5)

  The maximum horizontal displacement of embankment dam occurs in the middle of upstream and downstream dam slopes.

Finite element calculation model parameters of embankment dam are obtained by dynamic triaxial tests.

Seismic dynamic responses and residual deformation of embankment dam are analyzed.

With the increase of dam height, the acceleration distribution shows an obvious amplification effect.

The vertical displacement of embankment dam is larger along the dam axis and decreases in the upstream and downstream direction.

The maximum horizontal displacement of embankment dam occurs in the middle of upstream and downstream dam slopes.

Modular integrated construction (MiC) reengineers the traditional construction process. By introducing factory production and onsite assembly (OA) of modules, MiC reinvents construction projects' uncertainties and risk profiles. The OA stage constitutes the highest end of the MiC delivery and supply chains, where several inherited and symbiotic errors and risk events become realities, negatively impacting the MiC project's success. This study explored the severities of OA risk factors for MiC projects.

A comprehensive literature review, consultation of experts and a questionnaire survey of domain experts were conducted to assess the severity of fifteen OA risk factors for MiC projects. The risk severity index was used to compute and rank the severities of critical OA risk factors for MiC projects, followed by proposed mitigation strategies.

The study revealed that the top five OA risk factors with the severest impact on MiC projects include modules installation discrepancies and errors, poor cooperation among critical onsite stakeholders, a mismatch between production schedules and site conditions, improper lifting equipment selection for onsite installation and site-fit rework due to discrepancies in drawings.

This study is the first to offer some important insights into the uncertainties that could compromise the OA objectives of MiC projects. It discussed risk management strategies for known and unknown OA risks and made a unique contribution to the theory, practice, and praxis of MiC supply chain risk management.

Modular integrated construction (MiC) is an innovative and effective manufacturing-based method of construction that has become the mainstream development direction of projects in Hong Kong (HK). However, large-scale promotion of MiC practice still needs efforts. A pressing concern is that the impact of relevant policies on stakeholders during project implementation is rarely explored in depth. Therefore, to fill the research gap, this study aims to investigate the influence of policies on stakeholders to drive the successful implementation of MiC in HK.

This study uses a strategy of multiple methods. First, a comprehensively literature review and survey were adopted to identify critical policies and stakeholders. Second, semi-structured interviews with 28 experts were conducted to quantify their relationships. Third, three policy–stakeholder networks at initiation, planning and design and construction stages were established using social network analysis.

Environmental protection policy, COVID-19 pandemic policy and environmental protection policy and quality acceptance standard for project completion are found to be the most important policies of the three stages, respectively. The HK government and developers are highlighted as prominent stakeholders influencing policy implementation at all three stages. The dynamics of the influence stakeholders receive from critical policies at different stages of MiC are discussed. Valuable recommendations are accordingly proposed to enhance the successful implementation of MiC projects from the perspective of various stakeholders.

This study contributes to the body of knowledge by considering the mediating influence of stakeholders during policy implementation in the MiC uptake, and is valuable in helping policymakers to deeply understand the influence of policies to further forward successful MiC implementation and practicality in HK.

The purpose of this paper is to explore the factors that influence migrant workers' household registration transfer willingness at both individual and urban levels and to provide empirical evidence on adjusting the household registration system to accommodate economic development and migrant workers' imbalances.

This paper adopts a hierarchical nonlinear model and examines individual and urban influencing factors of migrant workers' household registration transfer willingness, based on the data from China Migrants Dynamic Survey (CMDS) and the Urban Statistical Yearbooks.

This paper shows that: (1) multi-factors, such as age, education, marital status, household demographics, industry and migrant workers' contract coverage, have significant effects on migrant workers' household registration transfer willingness; (2) The urban public service equalization indicators, such as regional economic, educational resources, medical care and ecological quality, have significant effects on migrant workers' willingness to transfer household registration; (3) The heterogeneity of migrant workers' willingness to transfer household registration is significant in central, eastern and western China.

The authors provide a fresh perspective on population migration research in China and other countries worldwide based on the pull–push migration theory, which incorporates both individual and macro (urban) factors, enabling a comprehensive examination of the factors influencing household registration transfer willingness. This hierarchical ideology and approach (hierarchical nonlinear model) could be extended to investigate the influencing factors of various other human intentions and behaviors.

Micro approaches (individual perspective) have dominated existing studies examining the factors influencing migrant workers' household registration transfer willingness. The authors combine individual and urban perspectives and adopt a more comprehensive hierarchical nonlinear model to extend the empirical evidence and provide theoretical explanations for the above issues.