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Prefabricated building has been widely applied in the construction industry all over the world, which can significantly reduce labor consumption and improve construction efficiency compared with conventional approaches. During the construction of prefabricated buildings, the overall efficiency largely depends on the lifting sequence and path of each prefabricated component. To improve the efficiency and safety of the lifting process, this study proposes a framework for automatically optimizing the lifting path of prefabricated building components using building information modeling (BIM), improved 3D-A* and a physic-informed genetic algorithm (GA).

Firstly, the industry foundation class (IFC) schema for prefabricated buildings is established to enrich the semantic information of BIM. After extracting corresponding component attributes from BIM, the models of typical prefabricated components and their slings are simplified. Further, the slings and elements’ rotations are considered to build a safety bounding box. Secondly, an efficient 3D-A* is proposed for element path planning by integrating both safety factors and variable step size. Finally, an efficient GA is designed to obtain the optimal lifting sequence that satisfies physical constraints.

The proposed optimization framework is validated in a physics engine with a pilot project, which enables better understanding. The results show that the framework can intuitively and automatically generate the optimal lifting path for each type of prefabricated building component. Compared with traditional algorithms, the improved path planning algorithm significantly reduces the number of nodes computed by 91.48%, resulting in a notable decrease in search time by 75.68%.

In this study, a prefabricated component path planning framework based on the improved A* algorithm and GA is proposed for the first time. In addition, this study proposes a safety-bounding box that considers the effects of torsion and slinging of components during lifting. The semantic information of IFC for component lifting is enriched by taking into account lifting data such as binding positions, lifting methods, lifting angles and lifting offsets.

The literature on help-seeking at work has experienced significant growth in the past decades. However, our knowledge about this research domain remains fragmented and lacks sufficient theoretical integration. Therefore, this paper aims to comprehensively integrate the extant literature on help-seeking behavior at work and propose an overarching, organized framework to propel this field forward.

A state-of-the-art review and theoretical development on help-seeking at work are conducted.

First, the authors provide the conceptual clarity of its definitions, key characteristics, types and measurement techniques. Second, the authors develop a fine-grained and integrative process-based framework consisting of antecedents, proximal psychological mechanisms, subsequent influencing processes and distal outcomes to advance our understanding of seeking help in the workplace. Third, the authors offer a detailed agenda for future research to target opportunities within the field.

The current study is comprehensive in surveying the full body of knowledge on help-seeking at work. It uniquely provides a coherent overarching framework that organizes prior findings and channels future research. Additionally, this review paints a complete picture of what has been done and what needs to be done in the field. More research can be spurred based on our conceptual framework.

As an emerging visualization technology, virtual reality (VR) falls into the dilemma of having great potential but a low adoption degree in the architectural, engineering and construction (AEC) industry. However, few studies paid attention to studying barriers affecting VR’s adoption and their inner mechanisms. This makes AEC users hard to catch the key points for VR’s implementations. This study aims to get a clear structure of these barriers and provide insights for the improvement.

First, 12 major VR-AEC adoption barriers were identified by a systematic literature review and expert interviews (EI). Second, EI and similarity aggregation method were conducted to achieve reliable barrier relationships. Third, interpretive structural modeling was used to establish a multi-level model for barriers. Finally, ten crucial barriers were targeted with a comprehensive strategy framework.

The findings help AEC stakeholders get a thorough understanding of the VR-AEC adoption barriers. Besides, the inner mechanism among barriers is revealed and analyzed, followed by a systematic strategy framework. It is anticipated that users could conduct more effective VR-AEC promotions in the future.

This paper is the first to propose a comprehensive literature review on the VR-AEC adoption barriers. In addition, this paper is novel in building a hierarchy model that explores barriers’ inner mechanism, where structural strategies are proposed.

At present, teaching methods based on 2D drawings are still commonly used for educating students on the location of steel reinforcement bars in concrete. However, traditional teaching methods have limitations as students can find it difficult to understand 2D drawings. This study aims to develop an interactive and collaborative augmented reality environment (ICARE) using augmented reality (AR) technology to improve students' engagement in learning.

This study develops an ICARE prototype, which is organized into two stages: (1) The augmented teaching environment comprising of models and interactive components; (2) The AR collaborative application which uses Photon Unity Networking (PUN) plugin and Azure spatial anchors cloud service. The AR-based teaching environment runs with Universal Windows Platform (UWP) to enable development in the HoloLens 2 through Microsoft Visual Studio.

An experimental study was conducted, where 60 students were divided into three groups employing Drawings-based, building information modeling (BIM)-based and AR-based methods for teaching. After the test, the three groups of students were requested to complete a questionnaire. According to the analysis of the experimental results, the ICARE can improve students' comprehension, memory of learned materials and their ability to read and understand steel reinforcement drawings improving the quality of teaching, especially interactivity and engagement.

As illustrated in the experiments, the developed ICARE has outstanding performance over conventional approaches in civil engineering courses that can improve students' comprehension and memory of knowledge and their ability to read and understand steel bar drawings. This study provides empirical evidence that AR is a promising technology that can be integrated with traditional classroom instruction and can improve students' comprehension and memory of knowledge and their ability to read and understand steel bar drawings.

This paper aims to refine cross-organizational knowledge creation theory by exploring the knowledge conversion process of University-Industry (U-I) collaboration in Chinese aerospace industry. An ancient Chinese philosophy named I-Ching is also introduced to illustrate dynamics of knowledge creation to achieve enlightenment.

To describe the knowledge conversion tendency, a theoretical framework is developed by reference to Boisot’s (1995) Information Space. The application of the framework is described in the in-depth case study of micro-electrode manufacturing for aerospace vehicles. The dynamics of each stage in knowledge conversion is investigated with the implications from I-Ching.

Analysis of the results suggests that seven certain stages can be especially indicative of cross-organizational knowledge creation, namely: demand codification; knowledge gain; knowledge digestion; knowledge sharing; knowledge propagation; knowledge spillover and knowledge degeneration. A knowledge gain, digestion, sharing and propagation (GDSP) knowledge creation theory is developed accordingly. The form of knowledge in different stages is variable, the change among various forms is effectively explained by I-Ching.

There is clearly a strong requirement to test the framework further with other cases, such as sampling cases from different industries and of different firm scales. Besides, the knowledge creation processes on the organizational level and the individual level are quite different, which call for further study.

First, the theory helps firms to get a better understanding of the nature of U-I collaboration, that is to say, knowledge creation. That will, in turn, power the firm to take the initiative to participate in knowledge creation activities. Second, the illustration through I-Ching provides reasonable and easily understandable interpretations for Chinese corporate managers and executives. Traditional Chinese culture will be beneficial to make U-I collaborations more efficient and effective in China.

A new “GDSP knowledge creation theory” which enriches and advances the typical socialization, externalization, combination and internalization (SECI) knowledge creation theory in some aspects is proposed. The theory is deeply grounded in Chinese culture. Furthermore, the conversion of different knowledge forms in the theory is considered from a totally new perspective of ancient Chinese philosophy: I-Ching.

The purpose of this paper is to propose a “parachuting internationalization” metaphor as an alternative strategy that firms may choose to enter foreign markets compared to Uppsala Model and Born Global Model. This proposed new metaphor seeks to integrate the Uppsala and the Born Global Models to show that firms can attain success in the age of globalization if they are adept at devising creative strategies that help them overcome the challenges in a psychically distant environment.

This is a research paper that develops theoretical perspectives inspired by the Yin Yang thinking as well as the “thick descriptive” multiple case studies.

“Parachuting internationalization” embraces essential elements of the Born Global and the Uppsala Models and refers to a firm’s strategic targeting of markets with great potentials, correct positioning, swift actions, and fast learning, thus enabling the firm to circumvent the conventional wisdom of liability of foreignness, cultural distance, and psychic distance. “Parachuting internationalization” is essentially a GLOCAL approach which can be implemented in practice in terms of global vision, location, opportunity, capital, accelerated cultural learning and quick action, and logistics.

The “parachuting internationalization” metaphor is derived from interviews with four Scandinavian firms’ experiences that have entered into the Chinese market. This research reveals that two seemingly opposite approaches, i.e., the Born Global and the Uppsala Models, can be fruitfully combined and reconciled to generate a third novel approach.

To date, there has been little attempt to reconcile and/or integrate the Born Global and the Uppsala Models of internationalization. The paper enriches the ongoing debate on the internationalization of firms in the international business literature that has relied primarily on the Uppsala Model or Born Global Model. The study shows that a third way, i.e. the “parachuting internationalization” is both theoretically innovative and practically feasible.

The coordinated development of the urbanization and construction industry is crucial for the sustainable development of cities. However, the coupling relationship and coordination mechanism between them remain unclear. To bridge this gap, this study attempts to explore the level of coupling coordination between new urbanization and construction industry development and investigate the critical driving factors influencing their coupling coordination degree.

By referring to the existing literature, two index systems were established to evaluate the development level of the new urbanization and construction industry. The spatiotemporal characteristics of the coupled coordinated development of the new urbanization and construction industry in China from 2014 to 2020 were investigated using the coupling coordination model. The Markov chain and geographic detector were adopted to understand the transition probability and driving factors of the coupling coordination degree.

The results indicate that the coupling degree of China's new urbanization and construction industry is high, and the two systems exhibit obvious interaction phenomena. However, the construction industry in most provinces lags behind the new urbanization. A positive interactive relationship and coordination mechanism has not been established between the two systems. Furthermore, the  coupling contribution degree of the driving factors from high to low is as follows: market size > labor resource concentration > government investment ability > economic development level > industrial structure > production efficiency > technology level. Accordingly, a driving mechanism including market, policy, economic, and production technology drivers was developed.

This study contributes to the existing body of knowledge by providing a set of scientific analysis methods to address the deficiency of coordination mechanism research on new urbanization and the construction industry. The results also provide a theoretical basis for decision makers to develop differentiated sustainable development policies.

Impinging jets have been widely studied, and the addition of swirl has been found to be beneficial to heat transfer. As there is no literature on Reynolds-averaged Navier Stokes equations (RANS) nor experimental data of swirling jet flows generated by a rotating pipe, the purpose of this study is to fill such gap by providing results on the performance of this type of design.

As the flow has a different behaviour at different parts of the design, the same turbulent model cannot be used for the full domain. To overcome this complexity, the simulation is split into two coupled stages. This is an alternative to use the costly Reynold stress model (RSM) for the rotating pipe simulation and the SST k-ω model for the impingement.

The addition of swirl by means of a rotating pipe with a swirl intensity ranging from 0 up to 0.5 affects the velocity profiles, but has no remarkable effect on the spreading angle. The heat transfer is increased with respect to a non-swirling flow only at short nozzle-to-plate distances H/D < 6, where H is the distance and D is the diameter of the pipe. For the impinging zone, the highest average heat transfer is achieved at H/D = 5 with swirl intensity S = 0.5. This is the highest swirl studied in this work.

High-fidelity simulations or experimental analysis may provide reliable data for higher swirl intensities, which are not covered in this work.

This two-step approach and the data provided is of interest to other related investigations (e.g. using arrays of jets or other surfaces than flat plates).

This paper is the first of its kind RANS simulation of the heat transfer from a flat plate to a swirling impinging jet flow issuing from a rotating pipe. An extensive study of these computational fluid dynamics (CFD) simulations has been carried out with the emphasis of splitting the large domain into two parts to facilitate the use of different turbulent models and periodic boundary conditions for the flow confined in the pipe.

Selective laser melting (SLM) is a powder metallurgical (PM) additive manufacturing process whereby a three‐dimensional part is built in a layer‐wise manner. During the process, a high intensity laser beam selectively scans a powder bed according to the computer‐aided design data of the part to be produced and the powder metal particles are completely molten. The process is capable of producing near full density (∼98‐99 per cent relative density) and functional metallic parts with a high geometrical freedom. However, insufficient surface quality of produced parts is one of the important limitations of the process. The purpose of this study is to apply laser re‐melting using a continuous wave laser during SLM production of 316L stainless steel and Ti6Al4V parts to overcome this limitation.

After each layer is fully molten, the same slice data are used to re‐expose the layer for laser re‐melting. In this manner, laser re‐melting does not only improve the surface quality on the top surfaces, but also has the potential to change the microstructure and to improve the obtained density. The influence of laser re‐melting on the surface quality, density and microstructure is studied varying the operating parameters for re‐melting such as scan speed, laser power and scan spacing.

It is concluded that laser re‐melting is a promising method to enhance the density and surface quality of SLM parts at a cost of longer production times. Laser re‐melting improves the density to almost 100 per cent whereas 90 per cent enhancement is achieved in the surface quality of SLM parts after laser re‐melting. The microhardness is improved in the laser re‐molten zone if sufficiently high‐energy densities are provided, probably due to a fine‐cell size encountered in the microstructure.

There has been extensive research in the field of laser surface modification techniques, e.g. laser polishing, laser hardening and laser surface melting, applied to bulk materials produced by conventional manufacturing processes. However, those studies only relate to laser enhancement of surface or sub‐surface properties of parts produced using bulk material. They do not aim at enhancement of core material properties, nor surface enhancement of (rough) surfaces produced in a PM way by SLM. This study is carried out to cover the gap and analyze the advantages of laser re‐melting in the field of additive manufacturing.