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This paper aims to design an active shock absorber scheme for use in conjunction with a passive shock absorber to suppress the horizontal vibration of elevator cars in a smaller range and shorter time. The developed active shock absorber will also improve the safety and comfort of passengers driving in ultra-high-speed elevators.

A six-degree of freedom dynamic model is established according to the position and condition of the car. Then the active shock absorber and disturbance compensation-based adaptive control scheme are designed and simulated in MATLAB/Simulink. The results are analysed and compared with the traditional shock absorber.

The results show that, compared with traditional spring-based passive damping systems, the designed active shock absorber can reduce vibration displacement by 60%, peak acceleration by 50% and oscillation time by 2/3 and is more robust to different spring stiffness, damping coefficient and load.

The developed active shock absorber and its control algorithm can significantly reduce vibration amplitude and converged time. It can also adjust the damping strength according to the actual load of the elevator car, which is more suitable for high-speed elevators.

This study aims to manufacture alternative window shutters using waste cotton fabrics by stiffening using polyvinyl acetate (PVA) with vinyl acrylic binder solutions.

The manufactured fabrics were evaluated for their tensile strength, drapeability, bending length by weight and color fastness to light. And finally, an analysis of variance was done for each parameter.

As the percent of PVA with a vinyl acrylic solution and the number of layers increased, the tensile strength, drape coefficient (percent), bending length (cm), and color fastness to light increased in both directions. The percent of PVA with a vinyl acrylic solution and the number of layers are statistically significant for each response such as tensile strength, drape coefficient (percent), bending length (cm), color fastness to light and water repellency at a 95% confidence interval. Tensile strength, drape coefficient (%) and bending length (cm) are always greater in the warp direction than in the weft direction. The tensile strength, drape coefficient (percent), bending length (cm) and color fastness to light of treated fabrics samples are greater than those of the untreated fabrics.

The factory waste fabrics can be recycled into window shutters which will provide the cheaper raw material for window shutter manufacturers.

This study investigates the effects of vertical direction and rotation of English loan brand names in East Asian languages (Chinese and Korean) on processing fluency, perceived product quality and purchase intention.

Four experiments were conducted in China and Korea, employing a 2 (vertical direction: downward vs upward) X 3 (rotation: 0°/marquee vs 90° clockwise vs 90° counterclockwise) between-subjects factorial design.

The findings showed that when the English loan Chinese brand name was displayed downward, the marquee format was preferred, while counterclockwise rotation was favored when displayed upward. In Korean, clockwise rotation was preferred for downward presentation, while counterclockwise rotation was favored for upward presentation. The effects on purchase intention were mediated by processing fluency and perceived product quality.

This research provides practical implications for global manufacturers and retailers, offering guidance on presenting brand names in East Asian languages and optimizing product packaging designs. For Chinese consumers, the marquee format is recommended for downward-oriented brand names, while counterclockwise rotation is effective for upward orientation. For Korean consumers, clockwise rotation is favored for downward presentation and counterclockwise rotation is preferred for upward presentation. Understanding linguistic habits allows the tailoring of brand presentations, enhancing brand perception and consumer responses.

This study contributes to understanding the role of cultural and linguistic influences on consumer information processing and product perception in vertical presentations of brand names.

Selective laser sintering (SLS) is an essential technology in the field of additive manufacturing. However, SLS technology is limited by the traditional point-laser sintering method and has reached the bottleneck of efficiency improvement. This study aims to develop an image-shaped laser sintering (ISLS) system based on a digital micromirror device (DMD) to address this problem. The ISLS system uses an image-shaped laser light source with a size of 16 mm × 25.6 mm instead of the traditional SLS point-laser light source.

The ISLS system achieves large-area image-shaped sintering of polymer powder materials by moving the laser light source continuously in the x-direction and updating the sintering pattern synchronously, as well as by overlapping the splicing of adjacent sintering areas in the y-direction. A low-cost composite powder suitable for the ISLS system was prepared using polyether sulfone (PES), pinewood and carbon black (CB) powders as raw materials. Large-sized samples were fabricated using composite powder, and the microstructure, dimensional accuracy, geometric deviation, density, mechanical properties and feasible feature sizes were evaluated.

The experimental results demonstrate that the ISLS system is feasible and can print large-sized parts with good dimensional accuracy, acceptable geometric deviations, specific small-scale features and certain density and mechanical properties.

This study has achieved the transition from traditional point sintering mode to image-shaped surface sintering mode. It has provided a new approach to enhance the system performance of traditional SLS.

Stainless-steel electromagnetic shielding (EMS) fabrics are widely applied as protective materials against electromagnetic interference (EMI). However, these fabrics primarily shield electromagnetic waves through reflection, which can lead to the formation of resonance effects that severely compromise their protective capabilities and potentially cause secondary electromagnetic pollution in the external environment.

In this paper, carbon nanotube fibers are added via spacing method to replace some stainless-steel fibers to impart absorbing properties to stainless-steel EMS fabric. The shielding effectiveness (SE) of the EMS fabrics across various polarization directions is analyzed. Additionally, a spacing arrangement for the carbon nanotube fibers is designed. The EMS fabric with carbon nanotube fibers is manufactured using a semi-automatic sample loom, and its SE is tested using a small window method test box in both vertical and horizontal polarization directions.

According to the experimental data and electromagnetic theory analysis, it is determined that when the spacing between the carbon nanotube fibers is less than a specific distance, the SE of the stainless-steel EMS fabric significantly improves. The fabric exhibits stable absorbing properties within the tested frequency range, effectively addressing the issue of secondary damage that arises from relying solely on reflective shielding. Conversely, as the spacing between the carbon nanotube fibers exceeds this distance, the SE diminishes. Notably, the SE in the vertical polarization direction is substantially higher than that in the horizontal polarization direction at the same frequency.

This study provides a new path for the development of high-performance EMS fabrics with good wave-absorption characteristics and SE.

Component positioning is an important part of aircraft assembly, aiming at the problem that it is difficult to accurately fall into the corresponding ball socket for the ball head connected with aircraft component. This study aims to propose a ball head adaptive positioning method based on impedance control.

First, a target impedance model for ball head positioning is constructed, and a reference positioning trajectory is generated online based on the contact force between the ball head and the ball socket. Second, the target impedance parameters were optimized based on the artificial fish swarm algorithm. Third, to improve the robustness of the impedance controller in unknown environments, a controller is designed based on model reference adaptive control (MRAC) theory and an adaptive impedance control model is built in the Simulink environment. Finally, a series of ball head positioning experiments are carried out.

During the positioning of the ball head, the contact force between the ball head and the ball socket is maintained at a low level. After the positioning, the horizontal contact force between the ball head and the socket is less than 2 N. When the position of the contact environment has the same change during ball head positioning, the contact force between the ball head and the ball socket under standard impedance control will increase to 44 N, while the contact force of the ball head and the ball socket under adaptive impedance control will only increase to 19 N.

In this paper, impedance control is used to decouple the force-position relationship of the ball head during positioning, which makes the entire process of ball head positioning complete under low stress conditions. At the same time, by constructing an adaptive impedance controller based on MRAC, the robustness of the positioning system under changes in the contact environment position is greatly improved.

Contemporary technological disruptions are espoused as though they stimulate sustainable growth in the built environment through the Green Internet of Things (G-IoT). Learning from discipline-specific experiences, this paper articulates recent advancements in the knowledge and concepts of G-IoT in relation to the construction and smart city sectors. It provides a scoping review for G-IoT as an overlooked dimension. Attention was paid to modern circularity, cleaner production and sustainability as key benefits of G-IoT adoption in line with the United Nations’ Sustainable Development Goals (UN-SDGs). In addition, this study also investigates the current application and adoption strategies of G-IoT.

This study uses the Preferred Reporting Items for Systematic and Meta-Analyses (PRISMA) review approach. Resources are drawn from Scopus and Web of Science repositories using apt search strings that reflect applications of G-IoT in the built environment in relation to construction management, urban planning, societies and infrastructure. Thematic analysis was used to analyze pertinent themes in the retrieved articles.

G-IoT is an overlooked dimension in construction and smart cities so far. Thirty-three scholarly articles were reviewed from a total of 82 articles retrieved, from which five themes were identified: G-IoT in buildings, computing, sustainability, waste management and tracking and monitoring. Among other applications, findings show that G-IoT is prominent in smart urban services, healthcare, traffic management, green computing, environmental protection, site safety and waste management. Applicable strategies to hasten adoption include raising awareness, financial incentives, dedicated work approaches, G-IoT technologies and purposeful capacity building among stakeholders. The future of G-IoT in construction and smart city research is in smart drones, building information modeling, digital twins, 3D printing, green computing, robotics and policies that incentivize adoption.

This study adds to the normative literature on envisioning potential strategies for adoption and the future of G-IoT in construction and smart cities as an overlooked dimension. No previous study to date has reviewed pertinent literature in this area, intending to investigate the current applications, adoption strategies and future direction of G-IoT in construction and smart cities. Researchers can expand on the current study by exploring the identified G-IoT applications and adoption strategies in detail, and practitioners can develop implementation policies, regulations and guidelines for holistic G-IoT adoption.

The impact of building information modeling (BIM) on various aspects of project management has attracted much attention in the past decade. However, previous studies have focused on a particular facet of project management (e.g., safety, quality, facility management) and within identified target journals. Despite numerous existing studies, there is limited research on the mainstream research topics, gaps and future research directions on BIM in project management. This study aims to conduct a bibliometric and science mapping review of published articles on BIM in project management and to identify mainstream research topics, research gaps and future research directions in this domain.

A science mapping approach consisting of bibliometric search, scientometric analysis and qualitative discussion was used to analyze 521 journal articles that were retrieved from the Scopus database and related to BIM in project management. In the scientometric analysis, keyword co-occurrence analysis and document analysis were performed. This was followed by a qualitative discussion that seeks to propose a framework summarizing the interconnection between the mainstream research topics, research gaps and future research directions.

Six mainstream research topics were found including (1) BIM-enabled advanced digital technologies, (2) BIM-based reinforcement and enhancement, (3) BIM and project composition, (4) BIM project elements and attributes, (5) BIM-based collaboration and communication and (6) BIM-based information and data. Moreover, this study discussed six research gaps, namely, (1) integration of BIM and other digital technologies, (2) future maturity of BIM applications in project management, (3) application of BIM in project components and processes, (4) role of BIM application in project elements and attributes, (5) impact of collaboration and communication in BIM application and (6) stability of information and data interaction. Furthermore, future research directions were discussed.

The findings and proposed framework contribute to providing a deeper understanding to researchers, policymakers and practitioners in the development of related research and practice in the domain of BIM in project management, thus, promoting digital transformation in project management. Overall, it adds to the global knowledge domain in BIM and promotes the need for digital and data integration, BIM maturity and BIM collaboration.

This paper aims to explore the efficiency of natural ventilation in the bedrooms of typical two-storeyed row houses with newly reconfigured design that incorporate rooftop wind catchers and side windows to create cross ventilation.

A CFD program was used to assess average air velocity coefficient (Cv) in 32 airflow cases. Parameters include location of openings with respect to wind direction, inlet-to-outlet area ratio (IOR) and opening-to-floor area ratio (OFR).

The results reveal that indoor air velocities in the cases of air entering wind catchers are generally higher than those in the cases of air entering side windows while air velocities at the openings are the opposite. The IOR of 1:2 provides best results in terms of both velocities of the indoor air and velocities at the openings. Increasing the OFR from 20% to 50% generally improves indoor air velocities and airflow rates.

This study proved that the new solution of combining one-sided wind catchers and side windows can effectively solve the problem of ventilation uniquely existing in the conditions of typical row houses by catching prevailing wind from two opposite directions into multiple rooms. The results are given as non-dimensional air velocities, which can be interpreted with any climatic data, and therefore can be applied to row houses in any locations and climatic conditions. The findings can create a new and efficient design of row houses that benefits building industry.

The aim of this paper is to understand how systemic change agents influence the twin digital and green transitions. The authors build on agency-based theories to argue that transition pathways are influenced by a combination of place-based characteristics, the mobilisation and preferences of systemic change agents (such as local clusters), and the institutional and economic context. The conceptual framework defines the different steps of the twin transition, and it identifies how systemic change agents and geographic characteristics determine the direction and speed of the transition pathway.

This paper starts with a literature review to identify the different schools of thoughts on transition pathways and the twin transition, before developing a conceptual framework and deriving policy implications.

First, this paper argues that each transition involves three steps: framing, piloting and scaling. Each of these steps is driven by systemic change agents who engage local actors in trust-based collaboration, pool resources, create network effects and exchange information to source solutions for industry-level challenges. Second, the combination of place-based characteristics and the actions of local systemic change agents define the path of the transition and the new (post-transition) equilibrium. Finally, this paper sets out implications for policymakers who are interested in using systemic change agents to shape transition pathways in their local area.

Further research is needed to provide robust empirical evidence from a range of territorial realities for the hypotheses in this paper. Specifically, the role of systemic change agents, such as trade associations, regional organisations, clusters or research groupings, needs to be investigated more closely. These agents can play a key role in progressing the transition because they already focus on sourcing solutions to joint challenges and opportunities by exchanging information, engaging local actors in trust-based collaboration, pooling resources and fostering network effects and critical mass. Future research should investigate how policymakers can best leverage on these crucial actors to progress or steer transitions and how this varies depending on place-based characteristics. This could include, for instance, training activities, networking and collaboration (e.g. through the European Cluster Collaboration Platform) or clearer sign-posting the key next steps required for the transition.

This paper identifies specific ways in which local actors can influence the direction and speed of transitions at each stage of the transition: at the framing stage, political entrepreneurship can be fostered through collaboration and smooth information flows between different levels of governance, at the piloting stage, commercial and social entrepreneurship require effective knowledge sharing and a wide and open search for solutions which, in turn, may require capacity building at the local level and coordination across stakeholder groups and levels of governance and effective scaling up can be fostered through network effects, joint commitment from a broad range of stakeholders and pooling of resources to achieve economies of scale.

An important implication of the framework is that, if several places are undergoing a parallel or joint transition, the result may not be convergence between these places. Instead, different places may choose different end points and they may proceed at different speeds. For instance, in the context of the European Union’s green and digital transitions, it is unlikely that every region will transition to a similar level of digitisation or make steps in the same direction when it comes to sustainability.

This paper plugs a gap in understanding how systemic transitions unfold and how their speed and direction are influenced by different stakeholder groups. This paper develops a conceptual framework to define twin transition pathways and it analyses prominent place-based factors affecting these pathways.