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A relatively inexpensive and easy to operate custom built infrared thermography (IRT) system was developed and utilized for the detection and characterization of defects in Carbon-Carbon (C/C) composite aircraft brake disks. This method uses an active infrared thermography (IRT) approach, i.e. Flash Heating method, for a non-destructive evaluation (NDE) of C/C brake disk materials. The experimental results obtained from the developed system were then compared with commercial IRT turn-key system. In addition, Finite Element Analysis (FEA) was also carried out to determine the detectible defect depth and diameter of the defects in C/C composites to validate the experimental results. The experimental results were compared to the FEA results and it was found that they were in good agreement with one another.

The green innovation behavior of construction enterprises is the key to reducing the construction industry's carbon emissions and realizing the green transformation of the construction industry. The purpose of this study is to reveal the evolutionary mechanism of green innovation behavior in construction enterprises.

This study is based on resource-based theory, Porter's hypothesis and signaling theory. First, a measurement model of the green innovation behavior of construction enterprises was constructed from three aspects: environmental regulation, enterprise resources and public opinion through hierarchical analysis. Then, the state values of the measurement model of green innovation behavior of construction enterprises were calculated through the time series data from 2011–2018. Finally, the Markov chain model was used to predict the evolutionary trend of green innovation behavior of construction enterprises, and the accuracy of the prediction effect of the Markov chain model was verified using the time series data of 2019.

The Markov chain model of green innovation behavior of construction enterprises constructed in this study has high accuracy. This model finds that the transition of the growth state of green innovation behavior in China's construction industry is fluid and predicts the evolution trend of the innovation behavior of construction enterprises. In the future, the green innovation behavior of construction enterprises has a probability of 70.17% to be in a continuous growth state and 40.27% to be in a rapid growth state.

Based on the Markov chain model of green innovation behavior of construction enterprises, this study finds that the transition of the growth state of green innovation behavior of construction enterprises in China has the characteristics of liquidity. In addition, it reveals the development process of the green innovation behavior of construction enterprises from 2011–2018 and predicts the evolution trend of the green innovation behavior of construction enterprises.

The purpose of this paper is to design and develop a rotary three-dimensional (3D) printer for curved layer fused deposition modeling (CLFDM), and discuss some technical challenges in the development.

Some technical challenges include, but are not limited to, the machine design and control system, motion analysis and simulation, workspace and printing process analysis, curved layer slicing and tool path planning. Moreover, preliminary experiments are carried out to prove the feasibility of the design.

A rotary 3D printer for CLFDM has been designed and developed. Moreover, this printer can function as a polar 3D printer for flat layer additive manufacturing (AM). Compared with flat layer AM, CLFDM weakens the staircase effect and improves geometrical accuracy and mechanical properties. Hence, CLFDM is more suitable for parts with curved surfaces.

Double extruders have brought improved build speed. However, this paper is restricted to complex process planning and mechanical structures, which may lead to collisions during printing. Meanwhile, the rotation range of the nozzle is limited by mechanical structures, affecting the manufacturing capability of complex curved surfaces.

A novel rotary 3D printer, which has four degrees of freedom and double extruders, has been designed and manufactured. The investigation on the prototype has proved its capability of CLFDM. Besides, this rotary 3D printer has two working modes, which brings the possibility of flat layer AM and CLFDM.

The purpose of this paper is to present a Rao–Blackwellized particle filter (RBPF) approach for the visual simultaneous localization and mapping (SLAM) of small unmanned aerial vehicles (UAVs).

Measurements from inertial measurement unit, barometric altimeter and monocular camera are fused to estimate the state of the vehicle while building a feature map. In this SLAM framework, an extra factorization method is proposed to partition the vehicle model into subspaces as the internal and external states. The internal state is estimated by an extended Kalman filter (EKF). A particle filter is employed for the external state estimation and parallel EKFs are for the map management.

Simulation results indicate that the proposed approach is more stable and accurate than other existing marginalized particle filter-based SLAM algorithms. Experiments are also carried out to verify the effectiveness of this SLAM method by comparing with a referential global positioning system/inertial navigation system.

The main contribution of this paper is the theoretical derivation and experimental application of the Rao–Blackwellized visual SLAM algorithm with vehicle model partition for small UAVs.

Prefabricated housing is a construction method that largely reduces construction waste and promotes sustainable development. However, the adoption of this method of construction is inhibited by the lack of demand by consumers. The purpose of this research is to explore consumer education strategies aimed at overcoming prefabricated housing challenges in China.

The study conducted a systematic literature review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A comprehensive search was conducted using databases such as Scopus and Web of Science, without any restriction on publication date. A total of 33 relevant articles were retrieved and analyzed using the content analysis method. The findings were then summarized and presented using the tabulation technique.

This study identified several barriers to prefabricated housing, including negative perception, limited public understanding, risk-averse culture and lack of green value. To foster market demand, relevant authorities should consider implementing effective educational mechanisms, such as comparative advertising, social media marketing, school programs and critical adult education programs. These strategies can effectively overcome the existing negative perception, alleviate concerns and create a positive environment for the growth of prefabricated housing in China.

This research provides practical and theoretical implications by identifying key challenges to prefabricated housing and suggesting targeted educational strategies to address them. It offers valuable guidance for policymakers, industry stakeholders and researchers, contributing to the advancement of sustainable housing practices.

The surging market demand for green construction materials has brought opportunities for construction materials enterprises' greenwashing behavior (GWB). This study aims to establish the causal relationship among the influencing factors of GWB and reveal the key influencing factors from the perspective of Chinese construction materials enterprises under multi-agent interactions.

This study is based on stakeholder theory, resource-based theory and the green development behavior and performance of industrial enterprises (GDBP-IE). First, with the literature analysis, an index framework of the influencing factors of enterprises' GWB was constructed from five dimensions (including 15 factors): environmental regulation, public scrutiny, market environment, corporate resources and corporate green development (GD) performance. Second, the interactive relationship among influencing factors was obtained by a questionnaire survey. Finally, the data are processed and analyzed with the grey-DEMATEL (Decision-making Trial and Evaluation Laboratory) method.

Among the factors, corporate information transparency has the greatest impact on the other factors, and consumer green preferences are most influenced by others. The most critical and important factor is the corporate social performance factor. In China, corporate social performance, corporate information transparency, corporate size and media supervision are the key factors influencing the GWB of construction materials enterprises.

This study provides a new perspective on the literature related to GWB by considering multi-agent interactions and extends the evidence from the construction materials industry for research on the drivers or influencing factors of enterprises' bad environmental behavior. Furthermore, it adds insights from China for further research on the governance strategies of GWB in other countries.

This paper investigates the relationship between human capital, economic freedom, governance performance, and economic growth and whether institutional factors such as governance performance and economic freedom mediate the association between human capital and economic growth.

In this study, the authors apply the panel data regression method to verify five hypotheses and check the robustness of the empirical findings from four aspects (chow test, panel unit root test, granger test and generalized method of moments) based on the data covering China, India, Russia, Brazil and South Africa from 2000 to 2018.

After multiple tests with mixed methods, the empirical results show that the relationship between human capital and economic growth is not linear but inverted U-shaped. Furthermore, human capital has a positive effect on economic growth only in a certain period of time, and governance performance positively moderates the effect of human capital on economic growth in BRICS.

First, the impact of human capital on economic growth is not linear but an inverted U-shaped and governance performance moderates the effect of human capital on economic growth in BRICS. The study and research model enhances the authors’ insights on the advantage and challenges of human capital in the future. Second, the proposed multi-methods in the study accurately forecast economic growth which partially solves endogenous problems because of reverse causality.

Understanding the key locational and neighbourhood determinants and their accessibility is a topic of great interest to policymakers, planners and property valuers. In Northern Ireland, the high level of market segregation means that it is problematic to understand the nature of the relationship between house prices and the accessibility to services and prominent neighbourhood landmarks and amenities. Therefore, this paper aims to quantify and measure the (dis)amenity effects on house pricing levels within particular geographic housing sub-markets.

Most hedonic models are estimated using regression techniques which produce one coefficient for the entirety of the pricing distribution, culminating in a single marginal implicit price. This paper uses a quantile regression (QR) approach that provides a “more complete” depiction of the marginal impacts for different quantiles of the price distribution using sales data obtained from 3,780 house sales transactions within the Belfast Housing market over 2014.

The findings emerging from this research demonstrate that housing and market characteristics are valued differently across the quantile values and that conditional quantiles are asymmetrical. Pertinently, the findings demonstrate that ordinary least squares (OLS) coefficient estimates have a tendency to over or under specify the marginal mean conditional pricing effects because of their inability to adequately capture and comprehend the complex spatial relationships which exist across the pricing distribution.

Numerous studies have used OLS regression to measure the impact of key housing market externalities on house prices, providing a single estimate. This paper uses a QR approach to examine the impact of local amenities on house prices across the house price distribution.

With the rapid development in wired and wireless networks, the demand for network security system is rising rapidly due to more and more new applications introduced. The main factors that rate the encryption algorithms are its ability to secure and protect data against attacks, its speed and efficiency. In this paper, a reconfigurable network security design using multi-mode data encryption standard (DES) algorithm has been implemented with low complexity and low cost, which will also reduce the speed. The paper aims to discuss these issues.

The design can be easily reconfigured to 3DES (triple DES) which is more secure and more powerful in encryption and decryption, as one of the trick in designing 3DES is to reuse three instances of DES. The design can be used for wired and wireless network applications, and it has been described using VHDL and implemented in a reconfigurable Programmable System-on-Chip (PSoC). The hardware implementation has targeted Xilinx Spartan XC3S700-AN FPGA device.

The main idea of reducing the complexity for the hardware implementation is by optimizing the number of logic gates and LUTs of the design. The number of logic gates can be decreased by changing the way of writing the VHDL code and by optimizing the size of the chip.

The design has been tested in simulation and hardware levels, and the simulation results and performance are discussed.