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Robotic arms play a crucial role in various industrial operations, such as sorting, assembly, handling and spraying. However, traditional robotic arm control algorithms often struggle to adapt when faced with the challenge of dynamic obstacles. This paper aims to propose a dynamic obstacle avoidance method based on reinforcement learning to address real-time processing of dynamic obstacles.

This paper introduces an innovative method that introduces a feature extraction network that integrates gating mechanisms on the basis of traditional reinforcement learning algorithms. Additionally, an adaptive dynamic reward mechanism is designed to optimize the obstacle avoidance strategy.

Validation through the CoppeliaSim simulation environment and on-site testing has demonstrated the method's capability to effectively evade randomly moving obstacles, with a significant improvement in the convergence speed compared to traditional algorithms.

The proposed dynamic obstacle avoidance method based on Reinforcement Learning not only accomplishes the task of dynamic obstacle avoidance efficiently but also offers a distinct advantage in terms of convergence speed. This approach provides a novel solution to the obstacle avoidance methods for robotic arms.

Blockchain has the potential to facilitate a paradigm shift in the construction industry toward effectiveness, transparency and collaboration. However, there is currently a paucity of empirical evidence from real-world construction projects. This study aims to systematically review blockchain adoption barriers, investigate critical ones and propose corresponding solutions.

An integrated method was adopted in this research based on the technology–organization–environment (TOE) theory and fuzzy decision-making trial and evaluation laboratory (DEMATEL) approach. Blockchain adoption barriers were first presented using the TOE framework. Then, key barriers were identified based on the importance and causality analysis in the fuzzy DEMATEL. Several suggestions were proposed to facilitate blockchain diffusion from the standpoints of the government, the industry and construction organizations.

The results highlighted seven key barriers. Specifically, the construction industry is more concerned with environmental barriers, such as policy uncertainties (E2) and technology maturity (E3), while most technical barriers are causal factors, such as “interoperability (T4)” and “smart contracts' security (T2)”.

This study contributes to a better understanding of the problem associated with blockchain implementation and provides policymakers with recommendations.

Identified TOE barriers lay the groundwork for theoretical observations to comprehend the blockchain adoption problem. This research also applied the fuzzy method to blockchain adoption barrier analysis, which can reduce the uncertainty and subjectivity in expert evaluations with a small sample.

Aero-engine casings commonly use composite cylindrical shell structures with excellent properties such as corrosion resistance and fatigue resistance. Still, their vibration behavior is relatively complex and may cause fatigue vibration damage, so it is essential to analyze the vibration characteristics of composite cylindrical shells. The purpose of this paper is to analyze the vibration characteristics of multilayer composite cylindrical shells subjected to external pressures and having different interlayer thickness ratios and provide some theoretical basis for the fatigue damage prediction of cylindrical shell casing to ensure the safety and stability of the engine during flight.

Firstly, the vibration differential equation with external pressure is established based on Soedel theory considering nonlinear effects, while four symmetric boundary conditions are chosen to constrain the cylindrical shell. Then the Rayleigh–Ritz method, which is more efficient and accurate in calculating large structural systems, is applied to solve the problem, and the theoretical model of three-layer cylindrical shell under external pressure is established. The accuracy of the model is verified by comparing the data with the specialized literature. Subsequently, the effects of different external pressures and different thickness-to-diameter ratios, different length-to-diameter ratios and different interlayer thickness percentages on the natural frequency of multilayer composite cylindrical shells were investigated by control variable analysis.

The conclusions obtained show that the external pressure increases the natural frequency of the cylindrical shell and that the frequency characteristics of the cylindrical shell vary for different boundary conditions. The effect of length-to-diameter ratio, thickness-to-diameter ratio and the percentage of the thickness of the intermediate layer on the natural frequency of the cylindrical shell are significantly increased under external pressure. Because the presence of external pressure increases the frequency of the cylindrical shell by about 70%, it has almost no effect on the frequency at the minimum number of circumferential waves, and the effect on the frequency at the maximum number of circumferential waves is reduced to about 50%. The frequencies in the SL-SL boundary condition are all in perfect agreement with the S-S boundary condition under the influence of different influencing factors.

In this paper, the effect of external pressure and the natural properties of the cylindrical shell under external pressure on the cylindrical shell’s frequency is considered, emphasizing the effect of different layer thickness ratios on the frequency. This paper aims to summarize the changing law between the natural frequency of the cylindrical shell itself and different design parameters during the flight pressure process. Reliable theoretical predictions are provided for analyzing the vibrational behavior of shells subjected to external pressures in aerospace, as well as a database for the practical production of cylindrical shells.

This aim of the research is to explore the link between offline and online retail sales through a comprehensive analysis of 15 years of retail sales data in Great Britain. By quantifying the impact of online sales on offline sales and vice versa on different retail categories, the study seeks to expand upon prior research that often focused on unidirectional relationships or specific retail segments. With channel- and sector-specific dynamics, the present study aspires to shed light on the dynamics shaping the retail industry and provide valuable insights for retailers.

The present study draws on 15 years of retail sales data in Great Britain to examine the interplay between offline and online sales across various retail categories. By grounding the analysis in the theoretical underpinning of cross-channel synergies and dis-synergies and applying principles of substitution and complementarity in online and offline retail sales, the research aims to quantify how shifts in online retail influence offline sales and vice versa. The study follows a systematic analysis approach that includes analysis of seasonality, autocorrelation, correlation, lagged cross-correlation and time series regression to provide a holistic understanding of the strength and direction of the relationship.

Among the myriads of findings, the most noteworthy ones are these. It was found that offline sales tend to increase significantly when online sales increase and online sales also increase significantly when offline sales increase. However, the extent of influence offline sales have on online sales is lower than the extent of influence online sales have on offline sales. For instance, it was found that for every one-unit increase in online sales, on average, the offline sales of retail stores increase by 5.82 units, but for every one-unit increase in offline sales, on average, the online sales of retail stores increase only by 0.07 units. This pattern was found true for all categories for retail stores, with predominantly non-food stores showing the lowest increase (0.02) and non-store retails exhibiting the highest increase (0.23). Additionally, evidence suggested that the retail stores can expect a sizable level of offline sales when there are no online sales (β₀ = 5155474.1); however, this was not true for online sales if they have no offline sales.

The study deepens our insight into the complex interplay between offline and online sales in the retail sector by providing empirical evidence on how online sales and offline sales interact with each other in a retail setting. It also adds nuances to existing knowledge on the relationship between online and offline sales based on channel and sector-specific dynamics. Such findings, coming from the analysis of a whole retail economy, strengthen the existing body of literature and provide a solid foundation for future research in this area. However, the study would have benefited from including qualitative interviews of different categories of retailers to provide more context and depth on interpreting quantitative patterns.

The study provides practical guidance for retailers on how they can optimize their omnichannel strategies for maximum impact. It also provides insights into the changes in relationship in terms of channel-specific and sector-specific differences. This is particularly important for retailers who operate in those categories of retail as it provides them with an insight into how they can allocate their resources for reaping substantial benefits.

Despite the wealth of research exploring the link between online and offline retail sales, there remains a gap in understanding the complex relationship between these two. This study is one of the first to fill this gap by exploring the link through a comprehensive analysis of 15 years of retail sales data in Great Britain. With these channel- and sector-specific findings, this study adds to the growing body of literature that provides an understanding of the bidirectional relationships between offline and online sales. These strengths strengthen the existing body of literature and provide a solid foundation for future research in this area.

As a clean and renewable energy source, wind energy will become one of the main sources of new energy supply in the future. Relying on the stable and strong wind resources at sea, wind energy has great potential to become the primary energy. As a critical part of the wind turbine, the gearbox of a wind turbine often bears a large external load. Especially at sea, due to the effects of ocean corrosion, waves and wind, the burden of the wind turbine gearbox is greater, which brings great challenges to its reliability analysis. This study aims to systematically review the reliability research in wind turbine gearboxes and guide future research directions and challenges.

This study systematically reviews some design requirements and reliability analysis methods for wind turbine gearboxes. Then, it summarizes previous studies on wind load uncertainty modeling methods, including the processing of wind measurement data and the summary of three different classifications of random wind speed prediction models. Finally, existing reliability analysis studies on two major parts of the gearbox are described and summarized.

First, the basic knowledge of wind turbine gearboxes and their reliability analysis is introduced. The requirements and reliability analysis methods of wind turbine gearboxes are explained. Then, the processing methods of wind measurement data and three different random wind speed prediction models are described in detail. Furthermore, existing reliability analysis studies on two common parts of wind turbine gearboxes, gears and bearings, are summarized and classified, including a summary of bearing failure modes. Finally, three possible future research directions for wind turbine gearbox reliability analysis are discussed, namely, reliability research under the influence of multiple factors on gears, damage indicators of bearing failure modes and quantitative evaluation criteria for the overall dynamic characteristics of offshore wind turbine gearboxes and a summary is also given.

This paper aims to systematically introduce the relevant contents of wind turbine gearboxes and their reliability analysis. The contents of wind speed data processing, predictive modeling and reliability analysis of major components are also comprehensively reviewed, including the classification and principle introduction of these contents.

Asia is one of the most important economic regions of the world. The Kra Canal is considered as a potential maritime transportation node in global trade. Indeed, for centuries, a canal across the Kra isthmus in Thailand has been proposed as holding significant economic and logistical benefits through goods transfer and exchange, yet it remains unconstructed. Common tools in feasibility studies are PESTELE and SWOT analyses, which incorporate cost-benefit and value analyses. The purpose of this paper is to assess the feasibility of the Kra Canal using approaches to complement existing studies.

In this paper, we combine quantitative and qualitative methodologies to holistically assess the feasibility of the Kra Canal. Quantitatively, we consider the economic feasibility of the canal using Net Present Value to evaluate its potential financial benefits. Qualitatively, we then present expert perspectives gathered from in-depth interviews with field experts (n = 20) to identify key aspects of complexity related to the economic, political and overall feasibility of the canal.

We discuss the possibility of the canal’s construction and describe possible future impacts the canal could have on the region geopolitically, for example, in its role in China’s One Belt One Road initiative and also in how Singapore and Tanjung Pelapas in Malaysia might react. Ultimately, we find significant complexities with the Kra Canal project, ones which anyone contemplating its construction would, we argue, be wise to consider.

This paper combined qualitative and quantitative methods to explore the economic, political and overall feasibility of the Kra Canal. The methodologies and findings supplement past relevant studies and help evaluate the economic, political and overall feasibility of the Kra Canal’s investment project. This is particularly timely considering its potential ability as a route given recent geopolitical events and, for example, as part of China’s Belt and Road initiative and its ability to reduce carbon and sulphur emissions.

This paper aims to examine the management status quo of archaeological heritage in Vietnam seen in the case of Vuon Chuoi, a complex of Bronze Age sites located in Central Hanoi, which has been believed to be Hanoi’s first human settlement. Like other archaeological sites located in urban areas, this site has been under threat of destruction caused by land encroachment pressure. Although researchers have long waged a campaign for preservation, the dissensus among key stakeholders and the dispute over responsibility have left this site at the heart of an interminable polemic over legislation.

This research utilises a qualitative approach, and the primary data were collected throughout multiple field trips in 2019 and 2020. Several open-ended interviews were conducted with various state and nonstate actors involved in the Vuon Chuoi Complex’s management process. The discussion was also supported by analysing related legal documents retrieved from national archives and official online directories.

This paper dissects the current legislative and administrative framework applied in governing heritage in general and archaeological sites in Vietnam, in particular. The results indicate that existing flaws in Vietnam’s legal system are detectable, and the unsystematic organisation has led to deferment of the decision-making processes. Also, there is an apparent difference found in the attitude of the bodies in charge toward the treatment of listed and unlisted sites.

This research outlines that in the wake of urbanisation and industrialisation in Vietnam, a consensus among key stakeholders and an inclusive legal system are required to help preserve archaeological sites in urgent need of attention. Although several Vietnamese laws and regulations have been put into practice, they have shown critical barriers and gaps in conserving Vietnamese cultural heritage.

This study aims to integrate perspectives of transaction costs and capabilities to investigate how the configurational fit between outsourcing strategies, asset specificity of projects and the capabilities of general contractors could achieve high outsourcing performance.

Employing fuzzy-set qualitative comparative analysis, this study analyzes 31 outsourcing cases in construction projects to examine outsourcing performance under different combinations of transaction costs and capabilities.

The findings highlight six different but functionally equivalent configurations to high outsourcing performance, which vary according to attributes of projects and capabilities of contractors. Further, this study develops four context-dependent paths that link outsourcing strategies to high outsourcing performance: leading practitioner, collaborative manager, partnership dependent, and struggler.

How do contractors in construction projects navigate outsourcing practices to high performance? This study provides a configurational perspective to make outsourcing strategy decisions. Based on the firm’s capabilities and project asset specificity, contractors are encouraged to select from six different but functionally equivalent combinations and thereby four outsourcing strategies, namely leading practitioner, collaborative manager, partnership dependent, and struggler, to achieve high outsourcing performance.

This study contributes to the body of knowledge by offering a holistic perspective that integrates production and transaction costs to analyze contractors’ outsourcing strategies, contributing to the integration of the transaction cost perspective and capability perspective.

In response to the severe lag in tracking the response of the Stewart stability platform after adding overload, as well as the impact of nonlinear factors such as load and friction on stability accuracy, a new error attenuation function and a parallel stable platform active disturbance rejection control (ADRC) strategy combining cascade extended state observer (ESO) are proposed.

First, through kinematic modeling of the Stewart platform, the relationship between the desired pose and the control quantities of the six hydraulic cylinders is obtained. Then, a linear nonlinear disturbance observer was established to observe noise and load, to enhance the system’s anti-interference ability. Finally, verification was conducted through simulation.

Finally, stability analysis was conducted on the cascaded observer. Experiments were carried out on a parallel stable platform with six degrees of freedom involving rotation and translation. In comparison to traditional PID and ADRC control methods, the proposed control strategy not only endows the stable platform with strong antiload disturbance capability but also exhibits faster response speed and higher stability accuracy.

A new error attenuation function is designed to address the lack of smoothness at d in the error attenuation function of the ADRC controller, reducing the system ripple caused by it. Finally, a combination of linear and nonlinear ESOs is introduced to enhance the system's response speed and its ability to observe noise and load disturbances. Stability analysis of the cascade observer is carried out, and experiments are conducted on a six-degree-of-freedom parallel stable platform with both rotational and translational motion.

Rapid development in modern technologies has led to the transformation of global marketing strategies. Concerned stakeholders are also trying to alter the course of sustainable activities to exploit the marketing opportunities available in the digital world. Green gamification platforms have been developed and are being espoused by brands to enhance their image and support the sustainable development entrenched in users’ engagement with international brands. These platforms can transform consumers’ cognitive learning and decisions; however, their probable role is not explored in this context. A framework based on behavioural reasoning theory and value consumption theory is proposed to investigate associations of gamification value, cognitive reasoning factors, engagement and contextual boundary elements.

Partial least square structural equation modelling was applied to the data of 413 players, which were collected using a cross-sectional approach from qualified respondents.

Results indicate that gamification value inspires consumer engagement, with international brands and augments environmental consciousness; however, it also originates environmental complacency, but complacency does not significantly impact consumer engagement contrary to environmental consciousness. Besides, the interaction of a status-seeking lifestyle supplements environmental complacency and lessens the impression of environmental consciousness. The perceived sustainable image significantly enhances the influence of environmental consciousness towards consumer brand engagement, which is divergent from complacency.

This study offers implications for brands to utilize the digital uprising of gamification effectively in international markets. It proposes to transform the marketing strategies to bolster consumers’ engagement with international brands through gamification marketing strategies. This can help to achieve sustainable development goals worldwide more effectively.