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This paper aims to apply the spacing effect of capacitive imaging (CI) sensors to inspect and differentiate external flaws of the protective module, internal flaws of the protective module and external flaws of the metallic module in oil and gas pipelines simultaneously. Through experimental verification, a method for differentiating three distinct kinds of flaws derived from the spacing effect of CI sensors has been demonstrated.

A 3Dimensions (3D) model for simulating the inspection of these flaws was established by using COMSOL. A novel CI sensor with adjustable working electrode spacing was designed, and a modular CI system was developed to substantiate the theoretical findings with experimental evidence. A method for differentiating three distinct kinds of flaws derived from the spacing effect of CI sensors was established.

The results indicate that the method can successfully discriminate external flaws of the protective module, internal flaws of the protective module and external flaws of the metallic module using CI sensors.

The method for differentiating three distinct kinds of flaws derived from the spacing effect of CI sensors is vital for keeping the transportation safety of oil and gas pipelines.

This study aims to design and validate a theoretical model for capacitive imaging (CI) sensors that incorporates the interelectrode shielding and surrounding shielding electrodes. Through experimental verification, the effectiveness of the theoretical model in evaluating CI sensors equipped with shielding electrodes has been demonstrated.

The study begins by incorporating the interelectrode shielding and surrounding shielding electrodes of CI sensors into the theoretical model. A method for deriving the semianalytical model is proposed, using the renormalization group method and physical model. Based on random geometric parameters of CI sensors, capacitance values are calculated using both simulation models and theoretical models. Three different types of CI sensors with varying geometric parameters are designed and manufactured for experimental testing.

The study’s results indicate that the errors of the semianalytical model for the CI sensor are predominantly below 5%, with all errors falling below 10%. This suggests that the semianalytical model, derived using the renormalization group method, effectively evaluates CI sensors equipped with shielding electrodes. The experimental results demonstrate the efficacy of the theoretical model in accurately predicting the capacitance values of the CI sensors.

The theoretical model of CI sensors is described by incorporating the interelectrode shielding and surrounding shielding electrodes into the model. This comprehensive approach allows for a more accurate evaluation of the detecting capability of CI sensors, as well as optimization of their performance.

The weft-knitted two-side jacquard fabric has the characteristics of complicated design principle and hard technical design. The purpose of this paper is to realize the computer-aided design of weft-knitted two-side jacquard fabric, and provide a certain reference for the development of this type of fabric.

The weft-knitted two-side jacquard fabric is divided into weft-knitted two-side similar pattern jacquard fabric and weft-knitted two-side independent pattern jacquard fabric. In order to achieve the purpose of this study, firstly, the structural characteristic of weft-knitted two-side jacquard fabric is analyzed. Then, the design principle of weft-knitted two-side jacquard fabric is studied. Next, the technical model of weft-knitted two-side jacquard fabric is established. Finally, the CAD flow chart of weft-knitted two-side jacquard fabric is proposed to realize the rapid product development.

Based on the above method, through the development example of weft two-side similar pattern jacquard fabric and weft two-side independent pattern jacquard fabric, the computer-aided design of the weft two-side jacquard fabric is verified.

Because of limited research studies, three-dimensional computer-aided design of weft-knitted two-side jacquard fabric loop structure will be studied in the further research, and the technical design speed needs to be improved to meet the needs of large patterns and positioning patterns.

The computer-aided design of weft-knitted two-side jacquard fabric will offer a certain reference for product development, technical principles, performance research and computer simulation for the in-depth study of the fabric.

The computer-aided design of weft-knitted two-side jacquard fabric will simplify the fabric design process and improve the efficiency of new fabric development, and provide the industries a time-saving and cost-saving approach for new fabrics development.

The author analyzes the structural characteristic of the fabric by the physical fabric, summarizes design principle of the fabric through production process, uses mathematical methods to establish a three-dimensional technical model of the fabric, and proposes the CAD flow chart of weft-knitted two-side jacquard fabric, which has good theoretical significance and practice of weft-knitted two-side jacquard fabric.

This paper aims to research the effect of different concentrations for Nd(NO₃)₃ and Ce(NO₃)₃ on the microstructures and corrosion resistance of Ni-W-P composite coatings through electroless plating method.

Scanning electron microscope, attached energy dispersive spectroscopy system and X-ray diffraction were used in this work. Meanwhile, the immersion test and electrochemical tests were used to characterize the corrosion behavior of the coating.

The coatings prepared at 1.00 g·L⁻¹ Nd(NO₃)₃ exhibit a dense structure and high phosphorus content (12.38 wt.%). In addition, compared to the addition of Ce(NO₃)₃, when Nd(NO₃)₃ was introduced at a concentration of 1.00 g·L⁻¹, the minimum corrosion rate of the coating was 1.209 g·m⁻²·h⁻¹, with a noble E_corr (−0.29 V) and lower I_corr (8.29 × 10⁻⁴ A·cm⁻²).

The effects of rare earths on the deposition and corrosion resistance mechanisms of Ni-W-P composite coatings were explored, with the rare earth elements promoting the deposition of nickel and tungsten atoms. Simultaneously, the amorphization of the coating increases, which excellently enhances the corrosion resistance of the coating.

This paper aims to investigate the singular Hopf bifurcation and mixed mode oscillations (MMOs) in the perturbed Bonhoeffer-van der Pol (BVP) circuit. There is a singular periodic orbit constructed by the switching between the stable focus and large amplitude relaxation cycles. Using a generalized fast/slow analysis, the authors show the generation mechanism of two distinct kinds of MMOs.

The parametric modulation can be used to generate complicated dynamics. The BVP circuit is constructed as an example for second-order differential equation with periodic perturbation. Then the authors draw the bifurcation parameter diagram in terms of a containing two attractive regions, i.e. the stable relaxation cycle and the stable focus. The transition mechanism and characteristic features are investigated intensively by one-fast/two-slow analysis combined with bifurcation theory.

Periodic perturbation can suppress nonlinear circuit dynamic to a singular periodic orbit. The combination of these small oscillations with the large amplitude oscillations that occur due to canard cycles yields such MMOs. The results connect the theory of the singular Hopf bifurcation enabling easier calculations of where the oscillations occur.

By treating the perturbation as the second slow variable, the authors obtain that the MMOs are due to the canards in a supercritical case or in a subcritical case. This study can reveal the transition mechanism for multi-time scale characteristics in perturbed circuit. The information gained from such results can be extended to periodically perturbed circuits.

This paper aims to acquire the phase distribution and sealing performance of supercritical carbon dioxide (SCO₂) dry gas seals with phase transitions.

The SCO₂ spiral groove dry gas seal is taken as the research object. The finite differential method is applied to solve the governing equations. Furthermore, the phase distribution and the sealing performance are obtained. Compared to the ideal gas model, the effect of phase transitions on sealing performance is also explored.

Vaporization is likely to occur near the inner radius when SCO₂ dry gas seals are operated near the critical point. Whether phase transitions are considered in the model affects the sealing performance seriously. When phase transitions are considered, the sealing performance depends significantly on the working conditions, and unexpected results are produced when inlet conditions approach the critical point.

The numerical model for SCO₂ dry gas seals with phase transitions is established. The phase distribution and the sealing performance of SCO₂ dry gas seals are explored.

The purpose of this research is to measure incompatibilities between the manufacturing approaches (MA) used by the manufacturing industries, and those used for the off-site construction (OSC) of buildings. The aim is to explore which of these approaches could be integrated into OSC in a precise manner as viewed by architects as well as how this might occur.

An empirical research and empirical cycle (EC) was adopted as a methodological framework to measure incompatibilities. A combination of quantitative and qualitative mixed methods was explored through a literature-based case study of prefabricated houses and cars, nine real-life projects built by the second author's research team and the first-named author's practical experiences of leading these projects, based on a logic framework derived from the authors’ reflections of their architectural practices.

The findings quantitatively present the incompatibilities between cars (automobile bodies) and prefabricated houses. Design-related aspects have the most potential for integration (42.3% increment). The key lessons were identified as specific design philosophies and related guidelines for architects.

The findings are limited to single types of products (cars) and buildings (prefabricated houses) in particular regions. The key lessons just present a preliminary evaluation of the application of the design philosophies and related guidelines in nine real-life projects to comply with word limit constraints.

This study could help architects and other practitioners to locate and target and alleviated incompatibilities between MA and OSC. It could also precisely identify integration shortcomings to optimize decision-making as well as technical pathways for possible and effective breakthroughs.

This study provides fundamental research as a starting point for further discussion and development. A series of additional in-depth investigations combined with case studies are planned for the future. These could provide alternative study approaches to develop more appropriate architectural design methodologies and more streamlined processes.

The research contributes an alternative architectural perspective when measuring incompatibilities between MA and OSC. The results highlight the implications of precise measurement and provide guidance for architects. These facilitate the effective and successful integration of MA into OSC of buildings and promote the uptake of lean construction (LC) in OSC.

The virtual display of 3D garment is one of the most important features in a computer-aided garment design system. The purpose of this paper is to present a novel web-based 3D virtual display framework for the online design of warp-knitted seamless garment using the latest WebGL and HTML5 technologies.

Based on the feature-based parametric 3D human body model, the 3D model of skin-tight warp-knitted seamless garment is established using the geometric modeling method. By applying plane parameterization technology, the 3D garment model is then projected into corresponding 2D prototype pattern and a texture-mapping relationship is obtained. Finally, an online 3D virtual display application framework for warp-knitted seamless garment is implemented on modern WebGL-enabled web browsers using the latest WebGL and HTML5 technologies, which allow garment designers to globally access without installing any additional software or plugin.

Based on the 2D/3D model of warp-knitted seamless garment, an online 3D virtual display application running on modern WebGL-enabled web browser is implemented using the latest Javascript, WebGL and HTML5 technologies, which is proven to be an effective way for building the web-based 3D garment CAD systems.

This paper provides a parametric design method for warp-knitted seamless garment 2D/3D model, and web-based online virtual display of 3D warp-knitted seamless garment is implemented for the first time, which establishes the foundation for the web-based online computer-aided warp-knitted seamless garment design system.

An understanding of the impact of construction workers informal safety communication (CWISC), a form of parallel safety communication between workers, on safety performance among construction workers is crucial in order to develop effective strategies for improving safety performance in the construction industry. However, research remains scant on the impact of CWISC on safety performance. This study empirically aims to test the relationship between these important constructs.

Statistical analysis was used to examine the relationship in a hypothetical model with two latent variables; the exogenous variables represented by two groups of informal safety communication: friends and crew members and the endogenous variables represented by two groups of Safety performance metrics: safety compliance and safety participation, was tested.

The emergent findings revealed that there is a significant relationship between informal safety communication among crew members and safety compliance, and also between informal safety communication among friends on construction sites and safety participation. These findings emphasize the importance of fostering effective safety communication and collaboration within construction crews, as well as recognizing the influence friendships on safety performance. Stakeholders can leverage on these findings to implement policies to improve safety performance.

The study presents insightful practical knowledge on how CWISC impacts safety performance on construction sites. Practical recommendations for organizations are also proposed, e.g., development of team-building activities, platforms for sharing safety-related information and experiences, mentorship programs and initiatives that encourage social interaction among workers.