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Continua and discontinua coexist in natural rock materials. This paper aims to present an improved approach for addressing the mechanical response of rock masses based on the combined finite-discrete element method (FDEM) proposed by Munjiza.

Several algorithms have been programmed in the new approach. The algorithms include (1) a simpler and more efficient algorithm to calculate the contact force; (2) An algorithm for tangential contact force closer to the actual physical process; (3) a plastic yielding criterion (e.g. Mohr-Coulomb) to modify the elastic stress for fitting the mechanical behavior of elastoplastic materials; and (4) a complete code for the mechanical calculation to be implemented in Matrix Laboratory (MATLAB).

Three case studies, including two standard laboratory experiments (uniaxial compression and Brazilian split test) and one engineering-scale anti-dip slop model, are presented to illustrate the feasibility of the Y-Mat code and its ability to deal with multi-scale rock mechanics problems. The results, including the progressive failure process, failure mode and trajectory of each case, are acceptable compared to other corresponding studies. It is shown that, the code is capable of modeling geotechnical and geological engineering problems.

This article gives an improved FDEM-based numerical calculation code. And, feasibility of the code is verified through three cases. It can effectively solve the geotechnical and geological engineering problems.

This research proposes and examines a theoretical model grounded in anthropomorphism theory considering the curvilinear and linear relationships between service robot anthropomorphism and consumer usage intention and explores the mediating effect of perceived risk.

To examine the developed model, two complementary studies are designed. In Study 1, multi-time data of 511 participants show that service robot anthropomorphism inverts U-shaped (curvilinear) relationship on consumer usage intention and perceived risk mediates this curvilinear relationship. In Study 2, multi-source data of 460 volunteers are used to confirm the findings of Study 1 and examine that consumer empathy moderates the complex nonlinear effect of service robot anthropomorphism on perceived risk, and the indirect curvilinear effect of service robot anthropomorphism on consumer usage intention through perceived risk.

This research provides preliminary and yet important findings on how service robot anthropomorphism most likely is positively associated with consumer usage intention, i.e. the positively influence mechanism of service robot anthropomorphism on consumer usage intention.

This research provides preliminary and yet important findings on how service robot anthropomorphism most likely is positively associated with consumer usage intention, i.e. the positively influence mechanism of service robot anthropomorphism on consumer usage intention.

This study aims to investigate the impact of venture capital (VC) involvement on investment efficiency (IE) and its potential action mechanisms from the perspective of financial resource allocation.

Using data of Chinese firms between 2008 and 2020, and the propensity score matching–difference in differences method, the authors investigate the relationship between VC and IE.

The results show that VC involvement significantly promotes IE, and the effect exhibits an inverted U-shape dynamic over time. The authors find two mechanisms through which VC promotes IE: alleviating financing constraints and improving corporate governance. Supplementary tests indicate that VC institutions with high reputations play a significant role in enhancing IE; the promotion effect is more pronounced for firms in non-high-tech industries, firms facing higher industrial competition and firms located in areas with better property rights protection systems.

This study provides several original contributions. First, based on principal–agent and financing constraint theories, this study enhances the literature by revealing how VC drives the IE of newly public firms in China. Second, to the best of the authors’ knowledge, this is the first attempt to identify the mechanisms between VC and IE; Third, from an empirical perspective, besides discussing the average and dynamic effect of VC on IE, this study also explores the impact of the interaction between VC and market competition and property rights protection on IE.

This paper aims to use an ionic liquid (IL, [HMIM]PF₆) to improve the lubrication performance of liquid metal (LM) as a lithium grease additive and to expand the application range of LM.

In this paper, the different mass ratios of [HMIM]PF₆/LM mixtures were added into the lithium grease on a four-ball tribo-meter to investigate the effects of its tribological behavior. Scanning electron mircoscope/energy dispersive spectroscopy and X-ray photoelectron spectroscopy were used to reveal the anti-wear and friction-reducing mechanism of the additives.

When the load was used at 461 N, the average coefficient of friction (ACOF) and average wear scar diameter (AWSD) of steel ball Lubricated with grease with an optimal ratio of 2:3 ([HMIM]PF₆/LM) were reduced by 32.8% and 30.5%, respectively. Friction and wear mechanisms are ascribed to friction-induced additive components that can simultaneously form a composite lubrication film consisting of FePO₄, FeF₃, Ga₂O₃, In₂O₃ and SnO₂.

Compared with the pure lithium-based grease, when [HMIM]PF₆/LM was added with an optimal ratio of 2:3, the ACOF and AWSD were reduced by 12.4% from 0.097 to 0.085 and 23.8% from 552.117 µm to 420.590 µm under 392 N, respectively. When at 461 N, the ACOF and AWSD of steel ball were reduced by 32.8% from 0.122 to 0.082 and 30.5% from 715.714 µm to 497.472 µm, respectively. It was shown that the simultaneous addition of LM and [HMIM]PF₆ can form a composite lubrication film consisting of FePO₄, FeF₃, Ga₂O₃, In₂O₃ and SnO₂.

In this paper, [HMIM]P F₆ is added with LM simultaneously to improve the lubrication properties of lithium grease, and expand the application scope of LM.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2024-0017/

This study aims to empirically analyse the influence mechanism of perceived interactivity in real estate APP which affects consumers' psychological well-being. With the growing application of human–machine interaction in real estate APP, it is crucial to utilize human–machine interaction to stimulate perceived interactivity between humans and machines to positively impact consumers' psychological well-being and sustainable development of real estate APP. However, it is unclear whether perceived interactivity improves consumers' psychological well-being.

This study proposes and examines a theoretical model grounded in the perceived interactivity theory, considers the relationship between perceived interactivity and consumers' psychological well-being and explores the mediating effect of perceived value and the moderating role of privacy concerns. It takes real estate APP as the research object, analyses the data of 568 consumer samples collected through questionnaires and then employs structural equation modelling to explore and examine the proposed theoretical model of this study.

The findings are that perceived interactivity (i.e. human–human interaction and human–information interaction) positively influences perceived value, which in turn affects psychological well-being, and that perceived value partially mediates the effect of perceived interaction on psychological well-being. More important findings are that privacy concerns not only negatively moderate human–information interaction on perceived value, but also negatively moderate the indirect effects of human–information interaction on users' psychological well-being through perceived value.

This study expands the context on perceived interaction and psychological well-being in the field of real estate APP, validating the mediating role and boundary conditions of perceived interactivity created by human–machine interaction on consumers' psychological well-being, and suggesting positive implications for practitioners exploring human–machine interaction technologies to improve the perceived interaction between humans and machines and thus enhance consumer psychological well-being and span sustainable development of real estate APP.

This study aims to reduce the weight of the door, improve the operating efficiency and ensure the safety of vehicle operation.

Based on traditional aluminium alloy doors, a new type of honeycomb composite material was developed. Tests were conducted to determine the honeycomb compression resistance, honeycomb and skin shear performance, plate bending, thermal conductivity and environmental protection. Eight doors were developed based on the full-side open structure, and static strength and stiffness analyses were performed simultaneously. To solve door vibration problems, modal analysis and test were carried out.

The test results showed that the weight of the door was reduced by more than 40% whilst ensuring the strength and stiffness of the vehicle. The first–sixth-order test mode of the door was increased by more than 14% compared with existing aluminium alloy doors.

A new type of honeycomb composite material was used in this study. The test results showed that the weight of the door was reduced by more than 40% whilst ensuring the strength and stiffness of the vehicle. The 1st-to-6th order test mode of the door was increased by more than 14% compared with the existing aluminium alloy door.

This study aims to undertake a review of how carbon trading contributes to a reduction in emission of greenhouse gases (CHGs).

A narrative literature review approach was adopted to identify and synthesise existing literature using the Scopus and Web of Science databases. Articles were limited to the past 10 years to obtain the most current literature. The various ways in which carbon trading leads to reductions in emissions were identified and discussed.

The results showed that the main ways in which carbon trading contributes to reductions in emissions are through innovation in low-carbon technologies, restoration of ecosystems through offset money, development of renewable and clean energy and providing information on investment related to emissions.

The value of this study is to contribute to the built environment’s climate change mitigation agenda by identifying the role of carbon trading.

The output of this research identifies and contextualises the role carbon trading plays in the reduction of CHG emissions.

The purpose of this paper is to assess the spatial and temporal variations of extreme hot days (H*) and heat wave frequencies across Iran.

The authors used daily maximum temperature (T_max) data of 27 synoptic stations in Iran. These data were standardized using the mean and the standard deviation of each day of the year. An extreme hot day was defined when the Z score of daily maximum temperature of that day was equal or more than a given threshold fixed at 1.7, while a heat wave event was considered to occur when the Z score exceeds the threshold for at least three continuous days. According to these criteria, the annual frequency of extreme hot days and the number of heat waves were determined for all stations.

The trend analysis of H* shows a positive trend during the past two decades in Iran, with the maximum number of H* (110 cases) observed in 2010. A significant trend of the number of heat waves per year was also detected during 1991-2013 in all the stations. Overall, results indicate that Iran has experienced heat waves in recent years more often than its long-term average. There will be more frequent and intense hot days and heat waves across Iran until 2050, due to estimated increase of mean air temperature between 0.5-1.1 and 0.8-1.6 degree centigrade for Rcp2.6 and Rcp8.8 scenarios, respectively.

The trend analysis of hot days and heat wave frequencies is a particularly original aspect of this paper. It is very important for policy- and decision-makers especially in agriculture and health sectors of Iran to make some adaptation strategies for future frequent and intense hot days over Iran.