Search results

Laser point clouds are a 3D reconstruction method with wide range, high accuracy and strong adaptability. Therefore, the purpose is to discover a construction point cloud extraction method that can obtain complete information about the construction of rebar, facilitating construction quality inspection and tunnel data archiving, to reduce the cost and complexity of construction management.

Firstly, this paper analyzes the point cloud data of the tunnel during the construction phase, extracts the main features of the rebar data and proposes an M-E-L recognition method. Secondly, based on the actual conditions of the tunnel and the specifications of Chinese tunnel engineering, a rebar model experiment is designed to obtain experimental data. Finally, the feasibility and accuracy of the M-E-L recognition method are analyzed and tested based on the experimental data from the model.

Based on tunnel morphology characteristics, data preprocessing, Euclidean clustering and PCA shape extraction methods, a M-E-L identification algorithm is proposed for identifying secondary lining rebars in highway tunnel construction stages. The algorithm achieves 100% extraction of the first-layer rebars, allowing for the three-dimensional visualization of the on-site rebar situation. Subsequently, through data processing, rebar dimensions and spacings can be obtained. For the second-layer rebars, 55% extraction is achieved, providing information on the rebar skeleton and partial rebar details at the construction site. These extracted data can be further processed to verify compliance with construction requirements.

This paper introduces a laser point cloud method for double-layer rebar identification in tunnels. Current methods rely heavily on manual detection, lacking objectivity. Objective approaches for automatic rebar identification include image-based and LiDAR-based methods. Image-based methods are constrained by tunnel lighting conditions, while LiDAR focuses on straight rebar skeletons. Our research proposes a 3D point cloud recognition algorithm for tunnel lining rebar. This method can extract double-layer rebars and obtain construction rebar dimensions, enhancing management efficiency.

With the development of materials science and technology, composite workpieces are increasingly used. This paper aims to discuss a non-destructive testing (NDT) solution for semi-enclosed composite workpieces. A dual-robot system with one robot that grips an irregular-shaped ultrasonic probe (tool) is established.

According to robotics, this paper defines the orientations of the discrete points coordinate frames in trajectory and proposes an orientation constraint rule between the tool coordinate frame and the scanning trajectory. A four-posture calibration method for calibrating the transformation relationship of the irregular-shaped tool frame relative to the robot flange frame is presented in detail.

Calibration and verification experiments were performed, and good-quality C-scan images were obtained by applying the constraint rule and the calibration method. Experimental results show that the calibration method used to determine the tool centre point (TCP) position is correct, effective and efficient; the TCP orientation constraint rule can ensure the extension pole of the irregular-shaped ultrasonic probe is parallel to the axis of the semi-enclosed cylindrical workpieces; and the ultrasonic transducer axis is perpendicular to the surface of the workpiece.

This paper proposes a constraint method for the posture of an irregular-shaped tool in this scheme. Theoretical foundations for the four-posture calibration method of the irregular-shaped tool for dual-robot-assisted ultrasonic NDT are presented in detail. This strategy has been successfully applied in the NDT experiment of semi-enclosed composite workpieces.

This study aims to explore the influence of topic familiarity on the four stages of college students' learning search process.

This study clarified the effects of topic familiarity on students' learning search process by conducting a simulation experiment based on query formulation, information item selection, information sources and learning output.

The results characterized users' interaction behaviors in increasing topic familiarity through their use of more task descriptions as queries, increased reformulation of queries, construction of more purposeful query formulation, reduced attention to a topic's basic concept content and increased exploration of academic platform contents.

This study proposed three innovative indicators which were proposed to evaluate the effects of topic familiarity on college students' learning search process, and the adopted metrics were useful for observing differences in college students' learning output as their topic familiarity increased. It contributes to the understanding of a user's search process and learning output to support the optimization function of learning-related information search systems and improve their effect on the user's search process for learning.

The study aims to investigate the effect of entrepreneurial leadership (EL), competencies (ECs) and intentions (EIs) on enterprise performance (EP) via entrepreneurial resilience (ER) and risk-taking propensity (RTP).

Data were collected from 403 early-stage small and medium enterprise (SME) owners in Pakistan at two-time intervals and were analyzed using AMOS 22.

All predictors (i.e. EIs, EL and ECs) positively affected EP and ER, except for EL and ER. Furthermore, RTP and ER were serially mediated in linking EIs and ECs with EP but could not establish a link between EL and EP.

The findings reveal that the Pakistani government and business owners must focus on SMEs’ sustained development and prioritize ECs.

This paper is unique in nature, as understanding EIs, EL and ECs in a holistic framework has never been tested before in relation to EP.

This paper aims to verify the brand image effects of holding a sport mega-event by investigating the host city's influence on the country's branding, as a tourist destination.

This research considered the Rio 2016 Olympic Games and uses quantitative methods: exploratory factor analysis and regression. Data were collected by structured questionnaires with a sample of (n = 274) international respondents with high international travel experience.

Rio de Janeiro's 2016 host city image positively predicted Brazil's tourist destination image. Both cognitive and affective image dimensions of Rio as a host city predicted Brazil's destination image, but the cognitive image dimensions demonstrated more impact.

Even in a mega-event context, city marketing strategies should be planned and executed with a focus on the country's destination image.

The study contributes by focusing on presenting the importance of the host city image dimensions to the host country destination image in a sports mega-event context. The study investigated a new approach, the impacts of affective and cognitive dimensions in the overall destination image considering two connected destinations and the hosting of a sport mega-event, a condition not found in the literature thus far.

To examine the criminal laws and regulations on money laundering control in China and Hong Kong and to call for legal and institutional reforms in China.

This paper provides a comparative analysis and critically reviews the laws and regulations on money laundering control in China and Hong Kong.

China has shown a firm determination to combat money laundering since 2002. Reforms on Article 191 of the Criminal Law of the People's Republic of China (1997) and the institutional framework are called for to comply with the international standards of the FATF recommendations, the UN Convention against Transnational Organized Crime (2000) and the UN Convention against Corruption (2003) to control money laundering.

This paper highlights the problems and proposes both legal and institutional reforms on money laundering control in China.

This paper initiates the analytical research on the legal and institutional problems of money laundering control in China which had not been adequately explored.