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The phase-field method of interfacial damage is used to simulate the damage in composite structures containing the brittle orthotropic materials and their interface.

In the brittle fracture modeling, the strain tensor is decomposed into positive and negative parts characterizing tension and compression behaviors. By requiring an elastic energy preserving transformation involving the elastic stiffness tensor, these two strain parts must satisfy the orthogonality condition in the sense that the elastic stiffness tensor responds as a metric. However, most of the recent phase-field methods for brittle fracture do not verify this orthogonality condition. Additionally, to describe the damage in structures with anisotropic phases, recent studies have used multiple phase-field variables, with each preferential orientation represented by a phase-field variable to describe the bulk damage of component materials. This approach increases the complexity of simulation procedure. These disadvantages motivate the present study aimed at enhancing the simulation method.

The present study improves the phase-field method of interfacial damage by (1) incorporating the strain orthogonality condition into the phase-field method; (2) using only one phase-field variable instead of multiple phase-field variables to simulate damage in component orthotropic phases; and (3) investigating the interaction between interfacial damage and bulk damage as well as the effect of orientation tensor of preferential orientation in each orthotropic phase and the interfacial parameters on crack branching in composite structures.

Through several simulation examples, the present simulation method is proven to be accurate, effective, and helps the simulation process simpler than previous relevant methods.

Two friction models of Fe-Fe and Diamond-like carbon (DLC)-Fe were established by molecular dynamics (MD) method to simulate the friction behavior of traditional fracturing pump plunger and new DLC plunger from atomic scale. This paper aims to investigate the effects of temperature and load on the friction behavior between sealed nitrile butadiene rubber (NBR) and DLC films.

In this study, MD method is used to investigate the friction behavior and mechanism of DLC film on plungers and sealing NBR based on Fe-Fe system and DLC-Fe system.

The results show that the friction coefficient of DLC-Fe system exhibits a downward trend with increasing load and temperature. And even achieve a superlubricity state of 0.005 when the load is 1 GPa. Further research revealed that the low interaction energy between DLC and NBR promoted the proportion of atoms with larger shear strain in NBR matrix and the lower Fe layer in DLC-Fe system to be much lower than that in Fe-Fe system. In addition, the application of DLC film can effectively inhibit the temperature rise of friction interface, but will occur relatively large peak velocity.

In this paper, two MD models were established to simulate the friction behavior between fracturing pump plunger and sealing rubber. Through the analysis of mean square displacement, atomic temperature, velocity and Interaction energy, it can be seen that the application of DLC film has a positive effect on reducing the friction of NBR.

This study aims to study the influence of friction influencing factors between the wire rope and the liner on the safe use of the wire rope, which can provide guidance for the reliability design of the lifting system with strong dynamic response such as high speed, heavy load, etc., and improve the friction-driven stability of the system.

In this paper, the friction mechanism of wire rope and liner under the condition of excitation is investigated by means of wire rope-liner friction-vibration experimental platform and dynamic viscoelastic test of liner.

The results show that: With increasing excitation frequency, the friction between the three liner materials (G30, K25, PU) and the wire rope decreased, and the wear of the surface shape of the liners was greater. The dynamic thermomechanical analysis (DMA) test results showed that the viscoelasticity of the three liner materials increased when the frequency was increased.

Wire ropes are widely used in deep shaft hoisting and building elevators. Its operational reliability depends on whether there is sufficient friction between the wire rope and the friction liner, and whether the friction liner has good wear resistance. The study of the friction between the wire rope and the liner influencing factors is of great significance for the safe service of the wire rope.

The related results can provide guidance for the reliability design of lifting systems with strong dynamic response, such as high speed and heavy load, to improve the friction drive stability of the system.

With the increase of mining depth, to improve the transportation efficiency of the hoist used in deep and ultra-deep mines, as well as to ensure the safety and reliability of its operation, it is crucial that the large friction hoisting equipment has sufficient friction between the wire rope and the friction lining, as well as whether the friction lining has a good abrasion resistance.

Although the reinforcement of concrete and brick masonry with fiber-reinforced polymer (FRP) has been extensively researched, its application and impact on natural stone, especially in historic preservation, have received less attention. This study aims to examine the bond-slip characteristics of carbon fiber-reinforced polymer (CFRP) with two types of natural stone masonry, aiming to enhance their effectiveness in reinforcing historic structures. The stones studied include one from the Chouf-Lekdad region (A) and another from a historic structure in Sétif City (B). Both stones were strengthened using CFRP and carbon fiber fabric (CFF) through near-surface mount (NSM) and external bonding (EBR) techniques.

The interaction was assessed during the pull-out test by analyzing the stress transfer mechanisms, adhesion and deformation. This study also examines the effects of the following parameters on the bond between CFRP and stone: type of stone (A and B), type of reinforcement (plat CFRP and CFF), various notch shapes and sizes (bp, tp and Lb), and reinforcement techniques (NSM and EBR).

This study demonstrated the practicality and effectiveness of enhancing natural stone masonry of old buildings by integrating NSM and EBR techniques with CFRP. With a bond length of 30 mm, the pull-out force correlates with the strength of the stone. This indicates the importance of stone strength in obtaining better adhesion. The CFF–resin interface is more cohesive than the CFRP plate–resin interface because the resin penetrates the flexible CFF strip, ensuring better adhesion. In contrast, the CFRP plate interface is rigid and smooth. The results suggest that natural stone–CFRP adhesion is more effective than CFRP bonded to concrete and brick masonry due to the stone's strong resistance.

This experimental investigation provides new study into the bond-slip behavior of CFRP-reinforced natural stone masonry, filling the gap in existing research. The findings offer useful direction for creating FRP strengthening solutions that are specifically adapted to the properties of natural stone used in historic constructions. This study helps to improve preservation procedures by guiding the selection of reinforcing techniques, such as NSM versus EBR, and finding ideal bond lengths. This work's novelty stems from its ability to improve the structural integrity of culturally significant buildings while preserving their historical authenticity.

Machinery operating in a sand-dust environment is more susceptible to sand particles. The purpose of this paper is to investigate the impact of sand particle deposition rate, surface hardness and normal load on the tribological performance.

A predictive model to approximate the number of sand particles within the pin-on-disc contact surface is proposed. The efficacy of the model is validated through experimental method, which replicates a sand environment with two distinct particle deposition rates. Dry sliding friction experiments are also conducted using 45 carbon steel and H90 brass pins against GCr15 bearing steel discs.

When at high particle deposition rate [6.89 × 10^–5 g/(s·mm²)], the contact surfaces are separated by particles, resulting in an indirect metal contact. While at low deposition rate [6.08 × 10^–8 g/(s·mm²)], there is an alternating occurrence of direct and indirect metal contacts. In sand environment, the specific wear rate of 45 and H90 decreases by 50% and 33%, respectively, compared to non-sand environment when the applied load is 2.45 N. However, it is only 0.18% for 45 but remains significant at 25% for H90 at load of 9.8 N.

The predictive model and experimental method used in this paper are helpful for understanding the interaction between particles and sliding surfaces, thereby providing a solid foundation for material selection and load optimization of friction pairs influenced by sand-dust environments.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-05-2024-0155/

Conventional powder bed fusion systems, with their high costs, proprietary nature and restrictive fees, limit research opportunities. This study aims to unveil an affordable, open-source hardware, open-source software laser-based metal powder bed fusion system. Recognizing the distinction between DIY and open-source hardware is crucial for widespread acceptance.

The authors present a comprehensive system architecture using object process methodology for functions and architecture, a design structure matrix to model system dependencies and classical technical drawing exploded views for select subsystems. Modularization enables high adaptability, fostering potential adoption.

The fully open system enables unrestricted research, mirroring common industrial metal laser-based powder bed fusion (L-PBF) systems. While “open” systems are available for purchase, they remain closed-source, lacking source code and technical drawings sharing, hindering contribution and co-development. The authors’ is the pioneering and sole open-source metal L-PBF system, boasting 1,500+ print hours. A series of industrial and academic adopters are currently implementing the system.

The open system, slicer software and controller offer unique process control, supporting multimaterial printing. The authors shared the design on the OpenAM GitHub page under the CERN-OHL-P v2 Open Source Hardware license. While it is functional for additive manufacturing (e.g. aluminum, tool steel, titanium and stainless steel), the entire process chain is actively evolving, ideal for co-development with the additive manufacturing community.

This paper aims to use two different numerical approaches to simulate the induction welding process for a hybrid thermoplastic material, and the results have been validated experimentally.

The first approach used a numerical model that combines electromagnetism, heat transfer and solid mechanics in the same numerical environment using Hexagon Marc software. Simultaneously, a computationally efficient approach combined steady-state electromagnetism results at specific intervals in the Ansys EM suite with heat transfer and solid mechanics in Ansys Workbench.

The results from both numerical approaches showed a strong correlation with the experimental findings.

The current research offers valuable insights into enhancing induction welding procedures within the aerospace industry, as well as across broader industrial applications. The synergistic combination of numerical simulations and experimental validation served as a robust framework for future research endeavors aimed at enhancing the efficiency, reliability and quality of thermoplastic welding techniques.

This study aims to understand how unimanual and bimanual motor actions in the form of writing a message (handwriting and typing) influences consumer behavior intention and attitude.

Three studies have been conducted to understand how the method of writing (typing or handwriting) and moderator type of message (moderator: emotional vs. rational) can influence persuasion variables.

This paper shows evidence that bimanual and unimanual motor actions activate contralateral brain hemispheres and influence consumer behavior. Specifically, how the use of these motor actions leads to a change in behavior intention and attitude. Furthermore, how bidirectional behavior and role-reversal occurs when a unimanual vs bimanual motor actions are used to create an emotional or rational message.

This research focuses on explaining cognitive implications of unimanual vs bimanual motor actions (typing vs handwriting) on self and specifically on consumers when they are exposed to situations of producing/creating a message. Adding further evidence to persuasion, behavior intention and attitude research in embodied cognition (e.g. Petty and Cacioppo, 1986b; Briñol and Petty, 2008), the role of haptic interfaces in online marketing and consumer behavior (e.g. Brasel and Gips, 2015). The authors did not collect any FMRI data but it can be the future scope of this work.

The novel findings of bimanual and unimanual motor actions have a direct application to the current scenario of the online reviews/surveys, which have become a crucial point for e-commerce businesses and retailers that require customers to give feedback. Since, consumer emotions can influence behavioral outcomes and decision making through sensory cues (Abdolmohamad Sagha et. al, 2022; Haase Wiedmann and Labenz, 2022). From this perspective, depending on the mapping/recording of the felt emotionality or rationality by the customer, the feedback method can be oriented in a way to reduce the effect of negative reviews. Further applications are suggested for retailers, increasing prosocial or sustainable behavior and attitudes.

Marketing and advertising research conducted in different social settings is considered important in neuropsychology and neurophysiology research (Pozharliev et al., 2017). Therefore, this research can be extended to test in different social settings and marketing contexts, for example, in the virtual reality, metaverse and gamification. Thus, this research can serve as an avenue to examine the bimanual and unimanual motor actions in a scenario where the participants can combine several motor actions, for example, talking on the phone or walking while filling consumer reviews online/offline and wearing the VR devices like Apple Vision Pro and performing unimanual or bimanual motor actions.

Mapping of human behavior has always been done dependent on the cognition aspect and limited in its scope for embodied cognition. The results can be used for more direct and impactful ways of conducting surveys, feedback and handling communications for major businesses. In addition, it can be a helpful tool for message persuasion for a new brand or increasing awareness about sustainable consumption depending on typed or handwritten inputs by a potential consumer.

This paper focuses on a project to work on the digital library of Arab children's culture for sustainable development (DLACSD).

This project claims to link the past, present, and future by creating a platform that can grow to include not only works by adults but by children who inspire adults with their imagination and the joys they bring to the world.

This project addresses in phases the different aspects of the problem of the lack of material for Egyptian/Arab children at different stages in Arabic on the internet (with copyright law in mind). It is time to fill this gap by having a rich repository of stories, plays, games and songs for children in Arabic in a digital library to enrich the life of the child and to inform the world that much that is worthwhile is available in Arabic for parents, teachers, and children to enjoy.

Through reading samples of the works by Abdel-Tawab Youssef (1928–2015) by using the Dublin Core Elements, it will be informative to see how his writings address the United Nations Goals of Sustainable Development way before these Goals were discussed.

Writers for children, librarians, teachers, psychologists, literary critics, illustrators, and parents need a platform that makes material available to promote children’s culture in the Arab world and to introduce the world to what is of value for children in Arabic.

Currently, communication brings the world together and although the social media and the new technology have introduced problems that are serious, to say the least, collaborators on all levels must play an active role in redressing the social wrongs, especially those affecting children.

This ongoing project by members of a team who believe in interdisciplinarity and multidisciplinarity has taken the first step to create and develop (DLACSD).

This study is a pilot study exploring the usefulness and ease of use of a prototype VR PetCPR system and discusses the possibility of using it to facilitate pet healthcare skills acquisition. The designed VR PetCPR training system aims to provide pet healthcare professionals with an inexpensive, accessible and reliable CPR training tool and refine their skills in a controlled and simulated environment.

The study was conducted in a one-day workshop. The workshop consisted of the morning section (Section A) and the afternoon section (Section B). Section A was the knowledge acquisition stage. Section B is the VR PetCPR stage. Trainees were then given 30 min to experience the VR PetCPR set. When trainees were ready, they were required to complete two trials of dog CPR practice. After the practice, trainees completed the questionnaire and reported their attitudes toward VR PetCPR practice.

Overall, trainees held positive attitudes toward the effectiveness and usefulness of the VR PetCPR. After practicing skills via VR CPR, over half of the trainees responded that the system is effective in helping them understand the essential knowledge (e.g. operation status, operation positions, etc.) of performing CPR skills on a 30-pound dog. A significantly positive attitude was reported on trainees’ perceptions toward the ease of use of practicing their chest compression skills with the PetCPR. The positive attitudes significantly outnumbered the negative attitudes on explicit instruction and guidance, accessibility, convenience in practice and straightforward interface.

From data collected from 16 animal hospitals in the United States, Europe and Australia with 709 cases, 147 dogs (28%) and 58 cats (30%) temporarily attained ROSC during CPR, and 14 dogs (3%) and four cats (2%) survived to hospital discharge. Training veterinary CPR techniques and implementing RECOVER guidelines still have a long way to go. However, recent virtual reality simulations for CPR training were mainly designed for human patients CPR (Issleib et al., 2021; Liu et al., 2022; Almousa et al., 2019; Wong et al., 2018). The VR PetCPR remains a missing puzzle in the current VR training designs.