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The purpose of this paper is to describe a rapid and robust axisymmetric hybrid algorithm to create dynamic temporal and spatial charge distributions, or charge map, in the simulation of bipolar charge injection using Schottky emission and Fowler-Nordheim tunneling, field-dependent transport, recombination, and bulk and interfacial trapping/de-trapping for layered polymer films spanning the range from initial injection to near breakdown.

This hybrid algorithm uses a source distribution technique based on an axisymmetric boundary integral equation method (BIEM) to solve the Poisson equation and a fourth-order Runge-Kutta (RK4) method with an upwind scheme for time integration. Iterative stability is assured by satisfying the Courant-Friedrichs-Levy (CFL) stability criterion. Dynamic charge mapping is achieved by allowing conducting and insulating boundaries and material interfaces to be intuitively represented by equivalent free and bound charge distributions that collectively satisfy all local and far-field conditions.

Charge packets cause substantial increase of electric stress and could accelerate the breakdown of polymeric capacitors. Conditions for the creation of charge packets are identified and numerically demonstrated for a combination of impulsive step excitation, high charge injection, and discontinuous interface.

Metallized bi-axially oriented polypropylene (BOPP) dielectric thin film capacitor with self-clearing and enhanced current carrying capability offer an inexpensive and lightweight alternative for efficient power conditioning, energy storage, energy conversion, and pulsed power. The originality is the comprehensive physics and multi-dimensional modeling which span the dynamic range from initial injection to near breakdown. This model has been validated against some empirical data and may be used to identify failure mechanisms such as charge packets, gaseous voids, and electroluminescence. The value lies in the use of this model to develop mitigation strategies, including re-designs and materials matching, to avoid these failure mechanisms.

To deal with the present situation and recover after the COVID-19 pandemic, construction firms are required to recognise the trends in construction supply chain management (CSCM) for the upcoming years and determine the appropriate practices towards the trends for the improvement of construction activities in terms of strategy, tactic and operations. This paper aims to recognise key trends in CSCM and uses these trends as strategic criteria for the evaluation and prioritisation of lean construction (LC) tools at different project phases including design and architectural engineering, planning and control, on-site construction and safety management.

The integrated analytic hierarchy process–Delphi method is used to collect and analyse the data from construction experts to evaluate the importance levels of the CSCM trends and recommend the appropriate tools for LC practices to improve project performances.

Seven key CSCM trends are identified: lean supply chain management (SCM), supply chain (SC) integration, SC standardisation, SC problem-solving, SC information-sharing, SC flexibility and SC sustainability. Based on these trends, a set of prioritised lean tools are suggested for LC practices, in which “virtual design construction” (VDC) and “last planner system” are considered as the central tools. These two LC practices can be integrated with other effective tools to support the strategic, tactical and operational targets in construction supply chain (CSC) projects.

This study gives the managerial implications by developing an application framework of LC practices for CSC projects. The framework promotes “VDC” as a strategic tool for the phase of design and architectural engineering and considers “last planner system” as the central LC practice for the phase of project planning and control. The framework also focuses on the improvement of efficiency in construction operations by taking into account the aspects of on-site collaboration, problem-solving, improvement and safety.

Up to date, there is still a lack of researches in classifying and prioritising the significant LC tools for each project phase to deal with CSC issues in both breadth and depth. Thus, this study is performed to provide construction managers with the awareness of CSCM trends on which they can focus to have strategic criteria for selecting LC practices to improve CSC performances.

The architecture, engineering and construction (AEC) industry encounter substantial risks and challenges in its evolution towards sustainable development. International businesses, multinational AEC organisations, technical professionals, project and portfolio management organisations face global connectivity challenges between business units, especially during the outbreak of novel coronavirus pandemic, to manage construction megaprojects (CMPs). That raises the need to manage global connectivity as a main strategic goal of global organisations. This paper aims to investigate barriers to integrating lean construction (LC) practices and integrated project delivery (IPD) on CMPs towards the global integrated delivery (GID) transformative initiatives and develop future of work (FOW) global initiatives in contemporary multinational AEC organisations.

A two-stage quantitative and qualitative research approach is adopted. The qualitative research methodology consists of a literature review to appraise barriers to integrating LeanIPD&GID on CMPs. Barriers are arranged into six-factor clusters (FCs), with a conceptualisation of LeanIPD&GID, GID strategy placements and FOW global initiatives with multiple validations. This analysis also involved semi-structured interviews and focus group techniques. Stage two consisted of an empirical questionnaire survey that shaped the foundation of analysis and findings of 230 respondents from 23 countries with extensive cosmopolitan experience in the construction of megaprojects. The survey examined a set of 28 barriers to integrating LeanIPD&GID on CMPs resulting from a detailed analysis of extant literature after validation. Descriptive and inferential statistical tests were exploited for data analysis, percentage scoring analysis, principal component analysis (PCA) and eigenvalues were used to elaborate on clustered factors.

The research conceptualised LeanIPD&GID principles and proposed GID strategy placements for LeanIPD&GID transformative initiatives and FOW global initiatives. It concluded that the most significant barriers to integration of LeanIPD&GID on CMPs are “lack of mandatory building information modelling (BIM) and LC industry standards and regulations by governments”, “lack of involvement and support of governments”, “high costs of BIM software licenses”, “resistance of industry to change from traditional working practices” and “high initial investment in staff training costs of BIM”. PCA revealed the most significant FCs are “education and knowledge-related barriers”, “project objectives-related barriers” and “attitude-related barriers”. Awareness of BIM in the Middle East and North Africa (MENA) region is higher than LC and LC awareness is higher than IPD knowledge. Whilst BIM adoption in the MENA region is higher than LC; the second is still taking its first steps, whilst IPD has little implementation. LeanBIM is slightly integrated, whilst LeanIPD integration is almost not present.

The research findings, conclusion and recommendation and proposed GID strategy placements for LeanIPD&GID transformative initiatives to integrating LeanIPD&GID on CMPs. This will allow project key stakeholders to place emphasis on tackling LeanIPD&GID barriers identified in this research and commence GID strategies. The study has provided effective practical strategies for enhancing the integration of LeanIPD&GID transformative initiatives on CMPs.

The construction industry encounters substantial challenges in its evolution towards sustainable development and to the adoption of building information modelling (BIM) technology and lean construction (LC) practices on construction mega-projects. This study aims to present critical challenges and to investigate the interactions of BIM and LC on construction mega-projects encountered by key stakeholders in their efforts to integrate BIM and LC.

A qualitative research approach is adopted to introduce and validate LC principles and BIM functionalities resulting from a detailed analysis of extant literature, followed by a conceptual analysis of the interactions between BIM and LC on construction mega-projects. A quantitative questionnaire survey is then used. Descriptive and inferential statistical tests are used for data analysis, and analysis of variance tests elaborate and validate results.

The research yielded ten BIM functionalities and ten LC principles, which are categorised in four principle areas and four BIM functionality groups. A research framework for analysis of the interaction between BIM and LC is then compiled.

Research findings and the proposed framework will enhance the adoption of BIM and LC practices on construction mega-projects and allow project key stakeholders to place emphasis on tackling crucial challenges and barriers identified in this research. The framework will guide and stimulate research; and as such, the approach adopted up to this point is constructive. The identified interactions between BIM and LC on construction mega-projects show positive synergies between the two.

Construction management is enriched in many ways by direct and indirect support of lean construction concept. The objectives of this study are to assess the current level of awareness about lean construction practice, to identify the potential benefits and challenges to implement lean construction in the Bangladeshi construction industry and to prioritize them.

A comprehensive literature review has been done to design a questionnaire for the survey. The final questionnaire has been designed with 27 lean tools, 41 challenges, and seven benefits of implementing lean principles in the construction industry. A total of 164 valid responses have been collected from Bangladeshi construction practitioners involved in different types of construction organizations. The result has been analyzed by Relative Important Index (RII).

The findings revealed 41 challenges to implement lean construction with seven benefits in the Bangladeshi construction industry. The result shows that an appreciable number of respondent familiar with the techniques of lean construction but they don't practice. The findings have also pointed out that the lean construction approach adds a positive impact especially on quality, safety, cost, productivity, and environmental level. The top-ranked challenges to implementing lean construction are: lack of awareness and skill, poor management, traditional culture and attitude of employees, inadequate resources and equipment and nonuse of modern techniques and technologies.

This study reveals real scenario of lean construction in Bangladesh. It contributes to the body of knowledge, as it uncovers for the first time the awareness level, benefits and challenges to implement lean construction with reference to the social, economic and cultural context of Bangladesh. Exploring the findings, the study could help the stakeholders, construction firms, academician, researchers and government to focus their effort and resources on the significantly appropriate issues. Again, the study may be beneficial to developing countries especially in South Asia which share the same socio-economic status with Bangladesh.

As a problem-solving tool, the kaizen event (KE) is underutilised in practice. Assuming this is due to a lack of group process quality during those events, the authors aimed to grasp what is needed during high-quality KE meetings. Guided by the phased approach for structured problem-solving, the authors built and explored a measure for enriching future KE research.

Six phases were used to code all verbal contributions (N = 5,442) in 21 diverse, videotaped KE meetings. Resembling state space grids, the authors visualised the course of each meeting with line graphs which were shown to ten individual kaizen experts as well as to the filmed kaizen groups.

From their reactions to the graphs the authors extracted high-quality KE process characteristics. At the end of each phase, that should be enacted sequentially, explicit group consensus appeared to be crucial. Some of the groups spent too little time on a group-shared understanding of the problem and its root causes. Surprisingly, the mixed-methods data suggested that small and infrequent deviations (“jumps”) to another phase might be necessary for a high-quality process. According to the newly developed quantitative process measure, when groups often jump from one phase to a distant, previous or next phase, this relates to low KE process quality.

A refined conceptual model and research agenda are offered for generating better solutions during KEs, and the authors urge examinations of the effects of well-crafted KE training.

Built environment organisations face global challenges between business units, especially since the coronavirus pandemic (COVID-19) has profoundly disrupted the construction industry worldwide, including the management of construction megaprojects (CMPs). This research aims to develop a competency framework, for global integrated delivery (GID) transformative initiatives and future of work (FOW) global initiatives, to manage integration between lean construction (LC) practices and integrated project delivery (IPD) on CMPs in contemporary multinational engineering organisations.

“Mixed research methods” involves a two-stage quantitative and qualitative research approach. In the context of CMPs, stage one consisted of a qualitative research methodology comprising a literature review to examine competencies, COVID-19 impacts, responses and key drivers (KDs) to integrate LeanIPD&GID; stage one outcomes propose a conceptualisation of LeanIPD&GID, a competency framework and future of work (FOW) global initiatives. Stage two involved an empirical questionnaire survey for a set of 30 KDs arranged into five-factor clusters (FCs), 226 respondents from 23 countries with an extensive cosmopolitan experience; analysis adopted structural equation modelling (SEM), descriptive and inferential statistics, percentage scoring analysis, principal component analysis (PCA) and eigenvalues.

In the context of CMPs, stage one outcomes delivered a conceptualisation of LeanIPD&GID, a proposed competency framework and FOW global initiatives. Stage two concluded that the most significant KDs are “collaboration in design, construction works and engineering management,” “coordination and planning of construction work,” “senior organisational management support,” “boosting implementation of LC, and integrating project delivery” and “earlier and precise 3D visualisation of designs”. building information modelling (BIM) adoption in the MENA region is higher than LC; the second is still taking its first steps, while IPD has little implementation. LeanBIM is slightly integrated, while LeanIPD integration is almost not present.

The research findings, conceptualised LeanIPD&GID principles, a proposed competency framework and FOW global initiatives, provided future research streams and directions; the study has provided a competency framework and FOW global initiatives for effective practical strategies for enhancing integration of LeanIPD&GID transformative initiatives on CMPs and will allow project key stakeholders to place emphasis on boosting LeanIPD&GID KDs.

Built environment encounters substantial risks and challenges in its evolution towards sustainable development. International businesses and multinational engineering organisations face global connectivity challenges between business units, especially during the outbreak of the novel coronavirus pandemic (COVID-19), which has profoundly disrupted the construction industry throughout the world. That raises the need to manage global connectivity as a main strategic goal of multinational architecture, engineering and construction (AEC) organisations. This study aims to develop a strategic framework managing challenges of integrating lean construction (LC) and integrated project delivery (IPD) on construction megaprojects (CMPs) towards global integrated delivery (GID) transformative initiatives in multinational AEC organisations.

“Mixed research methods” involving a two-stage quantitative and qualitative research approach is adopted. The qualitative research methodology consists of a literature review to assess challenges to integrate LeanIPD&GID on CMPs. There is an assessment of conceptualisation of LeanIPD&GID and GID strategy placements, development of LeanIPD&GID integration framework and future of work (FOW) global initiatives with multiple validations. The analysis involved semi-structured interviews and focus group techniques. Stage 2 consisted of an empirical questionnaire survey that shaped the foundation of analysis and findings of 190 respondents from 23 countries with an extensive cosmopolitan experience of megaprojects in construction. The survey examined a set of 20 challenges to integrate LeanIPD&GID on CMPs resulting from a detailed analysis of extant literature after validation. Descriptive and inferential statistical tests were exploited for data analysis and percentage score analysis.

The research conceptualised LeanIPD&GID principles, proposed GID strategy placements, a framework for managing challenges of LeanIPD&GID transformative initiatives, FOW global initiatives and key performance indicators (KPIs). It concluded that the most significant challenges to integrate of LeanIPD&GID on CMPs are “lack of governmental incentives, policies, regulations or legal frameworks”, “lack of client’s awareness and IPD experience amongst key stakeholders”, “lack of organisation’s senior-management and client’s commitment to IPD approaches”, “resistance of industry to change from traditional procurement to IPD” and “lack of integrated synergies between LC, IPD working towards LeanIPD&GID”. Awareness of building information modelling (BIM) in the Middle East and North Africa (MENA) region is higher than LC, and LC awareness is higher than IPD knowledge. While BIM adoption in the MENA region is higher than LC, LC is still taking its first steps, and IPD has little implementation. LeanBIM is slightly integrated, while LeanIPD integration is almost not present.

The research findings, conclusions and recommendations provide a proposed framework for implementation, KPIs and GID strategy placements for LeanIPD&GID transformative initiatives to integrate LeanIPD&GID on CMPs and FOW global initiatives. This will allow project key stakeholders to place emphasis on managing LeanIPD&GID challenges identified in this research and commence GID strategies. The study has provided effective practical strategies for enhancing integration of LeanIPD&GID transformative initiatives on CMPs.

The construction industry encounters substantial challenges in its evolution towards sustainable development and in the adoption of building information modelling (BIM) technology and lean construction (LC) practices on construction mega-projects. This research aims to investigate the critical barriers encountered by key construction stakeholders in their efforts to integrate BIM and LC in the construction mega-projects.

A two-round Delphi survey shaped the foundation of aggregating consensus between an expert panel that examined a set of 28 barriers resulting from a detailed analysis of the extant literature. Descriptive and inferential statistical tests were exploited for data analysis, and interrater agreement analysis was used to elaborated and validate results.

The research concluded that the key barriers by descending order of significance are lack of mandatory BIM and LC industry standards and regulations by the government, resistance of the industry to change from traditional practices to LeanBIM, high cost of software licenses and training and running of BIM.

The research findings and the proposed mitigation strategy will enhance the application of BIM and LC practices in construction mega-projects and allow project key stakeholders to place emphasis on tackling the crucial challenges and barriers identified in this research.

This study aims to examine the impact of lean manufacturing (LM) on the financial performance of companies affected by emergency situations. It additionally explores the role of advanced manufacturing technologies (AMTs) in complementing LM to enhance financial performance in emergency and non-emergency situations.

Both survey and archival data were collected from 219 manufacturing companies in China. With longitudinal data collected before and after an emergency situation (i.e. Typhoon Rumbia), regression analysis was conducted to investigate the effects of LM and AMTs on financial performance in different contexts.

Our results reveal an inverted U-shaped relationship between LM and financial performance in the context of emergency. We also found that AMTs exerted a positive moderation effect on the inverted U-shaped relationship, indicating high levels of AMTs that mitigated the inefficiency of LM in coping with supply chain emergencies.

Through simultaneous investigation of LM and AMTs as bundles of practices and their fit with different contexts, this study takes a systems approach to fit that advances the application of contingency theory in the Operations Management literature to more complex patterns of fit.

This study illuminates how AMTs support LM practices in facilitating organizational performance in different contexts. Specifically, this study unravels the interaction mechanisms between AMTs and LM in influencing financial performance in emergency and non-emergency situations.