Browsing by Author "Zhou Y"

Now showing 1 - 6 of 6
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    Carbon footprint accounting of prefabricated buildings: A circular economy perspective
    (Elsevier Ltd, 2024-06-15) Li CZ; Tam VWY; Lai X; Zhou Y; Guo S
    Prefabricated buildings have gained significant attention as a solution for reducing carbon footprint in the construction industry. However, there is a lack of a comprehensive accounting approach tailored to the construction features of prefabricated buildings. To address this issue, this study develops a framework to account the life-cycle carbon footprint of prefabricated buildings within the circular economy principles. The developed framework is applied to a prefabricated building in Chengdu, China, revealing that a significant carbon footprint is attributed to the material production and transportation stages. Moreover, an uncertainty analysis is conducted based on Data Quality Indicator evaluation method and Monte Carlo Simulation to validate the accounting framework, and a minor deviation of 0.085 % between the uncertain and calculated values validates the proposed accounting framework. Furthermore, key processes to mitigate the carbon footprint are identified. The results show that cast-in-place concrete is a key process at the construction materials level. Building upon these findings, this study offers recommendations on accurately and efficiently accounting the carbon footprint of prefabricated buildings. The research findings contribute to fostering the accounting of the life-cycle carbon footprint for prefabricated buildings, establishing a theoretical and empirical basis for circular economy implementation in prefabricated buildings, and offering insights for making informed carbon emission reduction decisions in prefabricated buildings.
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    Developing a multi-objective optimization model for improving building's environmental performance over the whole design process
    (Elsevier Ltd, 2023-12-01) Zhou Y; Tam VWY; Le KN
    This study is built upon two previous articles which focus on identifying the key design variables affecting the life-cycle environmental impacts in each design stage of the building design process. This research aims to investigate the trade-offs between embodied and operational impacts and explore potential reduction in the total environmental impacts of a building by varying the identified design variables in each stage of the design process. A multi-objective optimization model based on BIM and LCA integration has been developed to find out the design solution with the optimal trade-offs between the embodied and operational impacts and the option with the minimal environmental impacts. Applying the proposed model to a mid-rise residential building, the results showed that the design process has the potential to lower the environmental impacts of the building by approximately 47.6 %. Moreover, the potential for reducing carbon emissions is greater in the early design stages, with the potential to lower emissions by up to 32.5 %, compared to the lower emission reduction potential of approximately 7.5 % in the detailed and construction design stages. Furthermore, solutions aimed at addressing the trade-off between embodied and operational impacts were identified in each design stage. The study provides an insight into the understanding of how building design can be optimized to mitigate environmental impacts.
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    Lean construction management: A catalyst for evaluating and enhancing prefabricated building project performance in China
    (Elsevier Ltd, 2024-10-01) Li CZ; Tam VWY; Hu M; Zhou Y
    The development of prefabricated construction in China has encountered challenges that prevent it from fully realizing its potential advantages. To overcome the challenges, this research examines the implementation of lean construction management in prefabricated building projects as a strategic approach to enhance their performance. Initially, this study examines the casual links between the driving factors of lean construction management and the performance indicators in prefabricated buildings by employing a structural equation model. Moreover, a fuzzy comprehensive evaluation method is used to assess the performance of a selected prefabricated building across the four dimensions: project schedule, quality, cost and safety. Furthermore, through the analysis and research above, this paper proposes a performance enhancement path for prefabricated building projects based on the key driving factors of lean construction management. The research identifies 23 driving factors and 16 performance indicators. 13 key driving factors are identified, including (1) accurate positioning and lean evaluation of the project, (2) identification of project product market demand, (3) modular collaborative design of the project implementation plan, (4) component production plant standardization, (5) production procurement costs reduction, (6) distance and cost of component transportation reduction, (7) lean transportation program plan, (8) construction and assembly costs reduction and waste elimination, (9) modular parallel construction, (10) lean construction assembly technology and management technology, (11) internal performance incentive mechanism of the project organization, (12) lean culture cultivation and lean management training, and (13) support from senior management. In addition, this research proposes a performance enhancement path for prefabricated buildings. The findings contribute to the theoretical knowledge of lean construction management in prefabricated building projects and offer valuable guidance for its practical implementation.
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    Life Cycle Assessment of the Environmental Impacts of Virgin Concrete Replacement by CO2 Concrete in a Residential Building
    (Springer Nature Singapore Pte Ltd, 2023-01-01) Ma M; Zhou Y; Tam VWY; Le KN; Duan W; Zhang L; Shah SP
    Concrete is one of the most consumed materials in construction, with 25 billion tons produced globally per year.
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    Simple and Efficient Transformation and Gene Editing of Marchantia polymorpha Spores
    (Wiley Periodicals LLC, 2025-05-27) Yorker RM; Deroles SC; Zhou Y; Tate JA; Davies KM; Albert NW
    Marchantia polymorpha (Marchantia) has become a model species for liverwort studies, owing to its rapid growth in vitro, ease of propagation, simple genetics, small genome, haploid-dominant life cycle, and because it is amenable to genetic transformation. Efficient transformation provides a foundation for many molecular and genetic analyses. The protocol described here is a simple and robust procedure for transforming Marchantia for a variety of applications, including gene overexpression and CRISPR genome editing. This simplified Agrobacterium tumefaciens-mediated transformation protocol targets spores, using common Agrobacterium strains GV3101 or EHA105, and overcomes challenges experienced in other methods. Spores are sterilized and distributed over sterile filter papers, which effectively retain spores and regenerating spores (known as sporelings). This approach enables the sporelings to be transferred to different agar growth media at different stages of transformation. A critical feature is preculturing the spores with acetosyringone (AS) prior to co-cultivation with Agrobacterium. This treatment profoundly enhances the transformation rate, particularly for Agrobacterium strain GV3101. GV3101 is preferred for its rapid growth rate, simple transformation, and lack of a recombinase (recA), stabilizing plasmids. The protocol is suitable for transforming Marchantia with constructs for CRISPR gene editing. Editing efficiency can be increased by introducing a heat-shock treatment during the transformation procedure, which increases the proportion of plants with larger edited sectors, facilitating mutant identification and propagation. Constructs and strategies for both overexpression and multiplex genome editing with sgRNA arrays using new and existing vectors are described. Using this spore transformation protocol for CRISPR gene editing, we routinely achieve 60% to 70% mutation rates, significantly reducing the effort required to generate and isolate mutants for functional analyses.
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    Stakeholder Mapping and Analysis of Off-Site Construction Projects: Utilizing a Power–Interest Matrix and the Fuzzy Logic Theory
    (MDPI (Basel, Switzerland), 2024-09-11) Zhu Q; Xi J; Hu X; Chong H-Y; Zhou Y; Lyu S; Shrestha PP
    Stakeholder management is a crucial component in the implementation of off-site construction (OSC) projects, while stakeholder mapping serves as a practical technique to facilitate an in-depth understanding of different project stakeholders. Various topics have been explored in the OSC stakeholder management field, but research on OSC stakeholder analysis based on stakeholder mapping is still lacking. This study addresses this gap by developing two-dimensional (2D) and three-dimensional (3D) stakeholder mapping models. Data were collected from 167 stakeholders involved in OSC projects. The 2D model utilizes a power–interest matrix to classify 12 identified OSC stakeholder groups, while the 3D model further explores these groups by incorporating an additional dimension of stakeholder salience across different stages of project implementation. The results show that OSC stakeholders predominantly fall into the “key players” or “minimal effort” categories across various project stages. Key players include the client, modular manufacturer, main contractor, government, and designer, while the public and industry organizations generally require minimal effort. Additionally, stakeholders such as the supervision company, supplier, and subcontractor play key roles at specific stages, with varying levels of salience throughout the project lifecycle, reflecting shifts in their influence and involvement. The findings contribute to stakeholder management knowledge by providing an in-depth understanding of OSC stakeholders’ interrelationships during project implementation, especially through uncovered stakeholder mapping in the OSC field.