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Accurate and timely cost prediction is critical to the success of construction projects which is still facing challenges especially at the early stage. In the context of rapid development of machine learning technology and the massive cost data from historical projects, this paper aims to propose a novel cost prediction model based on historical data with improved performance when only limited information about the new project is available.

The proposed approach combines regression analysis (RA) and artificial neural network (ANN) to build a novel hybrid cost prediction model with the former as front-end prediction and the latter as back-end correction. Firstly, the main factors influencing the cost of building projects are identified through literature research and subsequently screened by principal component analysis (PCA). Secondly the optimal RA model is determined through multi-model comparison and used for front-end prediction. Finally, ANN is applied to construct the error correction model. The hybrid RA-ANN model was trained and tested with cost data from 128 completed construction projects in China.

The results show that the hybrid cost prediction model has the advantages of both RA and ANN whose prediction accuracy is higher than that of RA and ANN only with the information such as total floor area, height and number of floors.

(1) The most critical influencing factors of the buildings’ cost are found out by means of PCA on the historical data. (2) A novel hybrid RA-ANN model is proposed which proved to have the advantages of both RA and ANN with higher accuracy. (3) The comparison among different models has been carried out which is helpful to future model selection.

Building information modeling (BIM) is recognized as one of the technologies to upgrade the informatization level of the architecture engineering and construction (AEC) industry. However, the level of BIM implementation in the construction phase lags behind other phases of the project. Assessing the level of BIM implementation in the construction phase from a system dynamics (SD) perspective can comprehensively understand the interrelationship of factors in the BIM implementation system, thereby developing effective strategies to enhance BIM implementation during the construction phase. This study aims to develop a model to investigate the level of BIM implementation in the construction phase.

An SD model which covered technical subsystem, organizational subsystem, economic subsystem and environmental subsystem was developed based on questionnaire survey data and literature review. Data from China were used for model validation and simulation.

The simulation results highlight that, in China, from 2021 to 2035, the ratio of BIM implementation in the construction phase will rise from 48.8% to 83.8%, BIM model quality will be improved from 27.6% to 77.2%. The values for variables “BIM platform”, “organizational structure of BIM” and “workflow of BIM” at 2035 will reach 65.6%, 72.9% and 72.8%, respectively. And the total benefits will reach 336.5 billion yuan in 2035. Furthermore, the findings reveal five factors to effectively promote the level of BIM implementation in the construction phase, including: policy support, number of BIM standards, owners demand for BIM, investment in BIM and strategic support for BIM.

This study provides beneficial insights to effectively enhance the implementation level of BIM in the construction phase. Meanwhile, the model developed in this study can be used to dynamically and quantitatively assess the changes in the level of BIM implementation caused by a measure.

Prefabricated construction (PC) will play a vital role in the transformation and upgrading of the construction industry in the future. However, high capital cost is currently one of the biggest obstacles to the application and promotion of PC in China. Clarifying the factors that affect the PC cost from the perspectives of stakeholders and exploring key cost control paths help to achieve effective cost management, but few studies have paid enough attention to this. Therefore, this research aims to explore the critical cost influencing factors (CIFs) and critical stakeholders of PC based on stakeholder theories and propose corresponding strategies for different stakeholders to reduce the cost of PC.

Based on the stakeholder theory and social network theory, literature review and two rounds of expert interviews were used to obtain the stakeholder-associated CIFs and their mutual effects, then the consistency of the data was tested. After that, social network analysis was applied to identify the critical CIFs, critical interaction and key stakeholders in PC cost control and mine the influence conduction paths between CIFs.

The results reveal that the cognition and attitude of developer and relevant standards and codes are the most critical CIFs while the government, developer and contractor are crucial to the cost control of PC. The findings further suggest that measures should be taken to reduce the transaction costs of the developer, and the contractor ought to efficiently apply information technology. Moreover, the collaborative work between designer and manufacturer can avoid unnecessary cost consumption.

This research combines stakeholder management and cost management in PC for the first time and explores the effective cost control paths. The research results can contribute to clarifying the key points of cost management for different stakeholders and improving the cost performance of PC projects.

Some papers have investigated the complex factors impacting building information modeling (BIM) application in prefabricated buildings (PBs), but few paid attention to their interaction relationships. Ignoring the fact that different factors are not isolated may lead to some key factors being overlooked without appropriate improvement strategies being proposed. This paper aims to analyze those factors and their inter-relationships, with the view to identify the critical factors and their interaction relationships so as to derive constructive strategies that would effectively facilitate BIM adoption in Chinese prefabrication.

First, factors influencing BIM application in prefabrication are extracted and collated by literature review, expert interview and analysis of PBs characteristics. Thereafter, an evaluation laboratory (decision-making trial and evaluation laboratory) and interpretive structural modeling are used to explore the relationships and hierarchy among the factors. Based on the degree of cause and centrality, critical factors are extracted and the interaction relationship are investigated.

The results show that BIM policies and standards for PBs are the main causal factors. The maturity of BIM software and BIM data interface for PBs, willingness to share data, the strategic goals of the enterprise, BIM law and BIM input and benefit are the main transitional factors while BIM staff and workflow, enterprise attitude, distribution of BIM liability and cooperation of participants are the main direct factors.

Based on the above findings, corresponding improvement strategies are proposed so as to promote BIM application in prefabrication and the rapid development of China’s PBs efficiently.

Prefabricated construction (PC) can benefit construction industry due to its high efficiency, energy saving, consumption reduction and safety. However, the high capital cost is a critical challenge hindering its development in China. The collaboration of PC stakeholders is conducive to improving cost management efficiency and optimizing resource allocation which has been ignored in previous studies. Therefore, this study aims to explore the collaboration paths of stakeholders in the process of solving critical cost influencing factors (CIFs) of PC to reduce costs.

Firstly, 25 CIFs and five main stakeholders that affect PC capital cost were identified through literature research and expert interviews. Then, questionnaires were used to investigate the relationship between stakeholders and CIFs from the perspectives of three stakeholder attributes of proximity, attitude and power, respectively. Finally, based on the survey data, three stakeholder-CIF networks from three attributes perspective and a comprehensive network were constructed and used for subsequent social network analysis.

(1) Stakeholders mainly show willingness and potential to collaborate on organization and management factors; (2) More stakeholders pay attention to incentive policies and the setting of prefabrication rates and assembly rates, while all stakeholders have the right to facilitate information and resource sharing in the PC supply chain; (3) The comprehensive network shows a core-periphery structure. As core stakeholders, contractor, designer and manufacturer are more likely to actively manage the 14 core CIFs.

This paper innovatively combined stakeholder and cost management in PC, and used two-mode network based on three stakeholder perspectives to reveal the collaboration potential and motivation of stakeholders in PC cost management. The findings not only provide guidance for stakeholders to find potential partners and optimize resource allocation in solving specific cost issues, but also facilitate stakeholders' sustainable collaboration to achieve PC's cost performance.

Although various concepts and techniques are introduced to the built environment to achieve a substantially efficient building production, the effective application of these methods in projects is of immense significance to the field of building construction. Among these initiatives, lean construction and building information modelling (BIM) are mainstream endeavours that share many common principles to improve the productivity of the built environment. This study aims to explore and explain how BIM-based integrated data management (IDM) facilitates the achievement of leanness in a built environment project.

This research is conducted through an ethnographic-action research that relies on the design-science approach and case study through a collaborative research project. As participants of the project, the researchers of this study cooperate with the practitioners to design the project approach and production workflows. Research data and evidence are obtained via participative observation, including direct observation, results of activities, unstructured meetings and self-analysis.

In this study, the project and production perspectives clarify the building design and production process, as well as analyse how BIM facilitates the achievement of leanness in building design and construction. BIM-based frameworks for IDM have been developed to handle miscellaneous information and data, as well as enhance multidisciplinary collaboration throughout the project life cycle. The role of the integrated BIM model as an information hub between the building design and building construction has been identified.

The project and production views of building and construction are used in this study because the research purpose is to link the BIM-based IDM to lean construction. Although this mixed approach can slightly undermine the theoretical foundation of this study, a substantially comprehensive understanding can be gained as well.

This study provides a new perspective to understand how BIM-based IDM contributes to lean construction.

This study provides new insights into IDM in a built environment project with project and production views and presents BIM-based frameworks for IDM to achieve lean construction through the BIM process.

The aim of this study is to report the effect of different content of calcium oxide on the process of electromelting magnesia.

The process of molten magnesia was analyzed by finite element simulation and proved by scanning electron microscope.

The results show that with the increase of CaO content, the maximum temperature appreciation increases from 3,616°C To 3,729°C, showing an approximate nonlinear evolution. Low thermal conductivity and low specific heat of CaO result in higher temperature. With the increase of CaO content and temperature, the maximum flow velocity of MgO slag increases from 0.043 to 1.34 mm/s. Under different initial CaO contents, the distribution trend of CaO volume fraction is basically the same, and the CaO volume fraction is evenly distributed between 50 and 225 mm in the furnace.

The influence of different contents of impurity calcium oxide on the process of electromelting magnesia was analyzed and a theoretical system was established.

Fashion and textile industry has confronted to participate with the sustainable industry and society proactively not by the government regulations, but by the shareholders or consumers driven with corporate social responsibility. The purpose of this paper is to consider methods applied for the sustainability of products according to Korean domestic fashion and textile companies and clothing types and to investigate the limitation of current sustainability methods of companies.

The study used document analysis and case studies of 396 companies. The study looked into newspapers, monthly magazines, and publications of fashion companies and internet web sites of almost every possible type that have been issued to date and analyzed the previous studies as well.

The companies’ strategies are of three groups, the uses of environmental friendly materials: 36.9 percent (natural fibers, recycled fibers and biodegradable fibers), apparel reuse: 4.5 percent (remodeling/alteration and transform/combination with more materials), and eco-marketing promotions: 58.6 percent. For women’s and casual wear section, the methods used with organic materials and the green-campaign messages appeared frequently, while in the men’s wear section, coolMapsi, 0or warm OnMapsi for business wear did a lot for the low indoor energy consumption, such as no neck-tie in the hot season or wearing underwear in the cold season.

Fashion and textile products have provided the key solutions for the generation’s happiness, identity, value, self-realization, health and role. There have been the low quality and similarity of fashion products from mass production and high speed and we should consider sustainability for the next generation and society. But the current problem in the industry is that most of eco-product developments are only short term. Also, from the high cost of eco materials and processes, there is a limited portion of sustainability section among total products and low design quality of fashion or the low profit outcomes.

This paper aims to present a new intelligent wall-climbing welding robot system for large-scale steel structure manufacture, which is composed of robot body, control system and welding system.

The authors design the robot system according to application requirements, validate the design through simulation and experiments and use the robot in actual production.

Experimental results show that the robot system satisfies the demands of automatic welding of large-scale ferromagnetic structure, which contributes much to on-site manufacturing of such structures.

The robot can work with better quality and efficiency compared with manual welding and other semi-automatic welding devices, which can much improve large-scale steel structure manufacturing.

The robot system is a novel solution for large-scale steel structures welding. There are three major advantages: the robot body with reliable adsorption ability, large payload capability and good mobility which meet the requirements of welding; the control system with good welding seam tracking accuracy and intelligent automatic welding ability; and friendly human – computer interface which makes the robot easy to use.

Among others in South Vietnam, the Temple of Literature in Vinh Long is the only one that has preserved its original form and layout. As such in 1991, the temple was recognized by the Ministry of Culture as a national-level historical and cultural relic. Nevertheless, the temple has been neither studied nor documented to any great depth. Only a few historical descriptions for local tour guidebooks and photo catalogs exist. Therefore this paper aims to initially record heritage values, spatial characteristics and the process of major changes, while documenting the current state of the temple structure and carrying out on-site inspections to survey the buildings.

This paper outlines the collection of survey data through field survey and provides an overview of the existing significant heritage factors of the Temple of Literature in Vinh Long by comparative examination in relation to other surviving temples and analyzing its unique spatial characteristics and indigenous cultural decorations in detail.

Although the layout of the temples was influenced by the Chinese Confucius's principles and the notion of Feng Shui, it is evident from the study that the design of the temple has many architectural elements that reveal Vietnam's unique culture and local features. In particular, the Temple of Literature in Vinh Long was a symbol of feudal education, symbolizing sacred traditional values in the field of education for the people of Vinh Long province. Stone steles recorded names of all contributors related to the construction and restoration of the temple with sincere gratitude. Moreover, many of the decorative motifs contain many indigenous cultural and artistic values of Vietnam, reflecting traditional Vietnamese beliefs and ethnographic features.

By comparatively analyzing the temple with others, it reveals the unique spatial features, layouts, changes and evolutions of the temple. Unlike the oldest and the largest Temple of Literature in Hanoi, the temples in the South are much smaller in terms of complex sizes and the number of buildings. They are mostly composed of a singular structure, the Attained Talent House, with some basic gates and water features interwoven within the landscape of the site. Based on the elementary layout, some subsidiary buildings were added according to the needs and site conditions, and in accordance with the bilateral axis.

The awareness and preservation of the architectural features of the local temple are needed to protect heritage monuments and to enhance cultural resources as part of securing Vietnamese ideology for a longer period of time. While the interest in historic preservation and conservation activities of heritage buildings in Vietnam has slowly grown in attention over the last decade, it is evident that many opportunities remain. It is hoped that this research is a small step toward further research, education and advocacy in the preservation of historic buildings in Vietnam.

The introduction of Chinese Confucian thought to Vietnam was one of the most substantial influences in Vietnamese intellectual history. Despite being an important part of the nation's architectural, cultural and intellectual heritage sites, the study and documentation of the Temples of Literature have been relatively neglected or marginalized. Accordingly, this study is significant to reveal not only the values and unique heritage characteristics of the temple, but also to prioritize resources for continued study and preservation.