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This paper aims to study the impacts of groundwater seepage on artificial freezing process of gravel strata, the temperature field characteristics of the strata, and the strata process, closure time and thickness evolution mechanism of the frozen wall.

In this paper several laboratory model tests were conducted, considering different groundwater seepage rate.

The results show that there is a significant coupling effect between the cold diffusion of artificial freezing pipes and groundwater seepage; when there is no seepage, temperature fields upstream and downstream of the gravel strata are symmetrically distributed, and the thickness of the frozen soil column/frozen wall is consistent during artificial freezing; groundwater seepage causes significant asymmetry in the temperature fields upstream and downstream of the gravel strata, and the greater the seepage rate, the more obvious the asymmetry; the frozen wall closure time increases linearly with the increase in the groundwater seepage rate, and specifically, the time length under seepage rate of 5.00 m d⁻¹ is 3.2 times longer than that under no seepage; due to the erosion from groundwater seepage, the thickness of the upstream frozen wall decreases linearly with the seepage velocity, while that of the downstream frozen wall increases linearly, resulting in a saddle-shaped frozen wall.

The research results are beneficial to the optimum design and risk control of artificial freezing process in gravel strata.

The interruption of on-campus teaching and learning, due to the COVID-19 pandemic, forced universities around the globe to rethink their pedagogical models and adopt innovative strategies and approaches that enabled continuity of learning. Engineering schools and faculties were faced with the challenge of how to continue to engage students with the practical component of coursework, especially in terms of lab work and experimentation, which are mandatory requirements for degree awards.

This study documents how the Faculty of Engineering in a university in Oman engaged students with the practical component of their course during the pandemic by launching the remote DoIt@Home Lab. The DoIt@Home Lab approach included the design and development of video recorded labs, virtual labs, simulation exercises and DoIt@Home experiments which were provided to students as teaching tools and guides to conducting home experiments remotely.

This study presents the DoIt@Home Lab approach introduced to Year 2 Chemistry for engineering students. Students' grades improved by 11% over the previous year when the course was delivered face-to-face. Failure rates dropped by 8% while the number of students earning a 3.25 grade point average (GPA) or higher increased by 18%.

The DoIt@Home Lab for engineering courses could enhance students' learning experience and create an effective remote learning environment. While the DoIt@Home Lab was created to supplement on-campus activity in the event of a temporary disruption, it can also be used to supplement regular face-to-face program delivery.

This study aims to computational numerical simulations to clarify and explore the influences of periodic cellular lattice (PCL) morphological parameters – such as lattice structure topology (simple cubic, body-centered cubic, z-reinforced body-centered cubic [BCCZ], face-centered cubic and z-reinforced face-centered cubic [FCCZ] lattice structures) and porosity value ( ) – on the thermal-hydraulic characteristics of the novel trussed fin-and-elliptical tube heat exchanger (FETHX), which has led to a deeper understanding of the superior heat transfer enhancement ability of the PCL structure.

A three-dimensional computational fluid dynamics (CFD) model is proposed in this paper to provide better understanding of the fluid flow and heat transfer behavior of the PCL structures in the trussed FETHXs associated with different structure topologies and high-porosities. The flow governing equations of the trussed FETHX are solved by the CFD software ANSYS CFX® and use the Menter SST turbulence model to accurately predict flow characteristics in the fluid flow region.

The thermal-hydraulic performance benchmarks analysis – such as field synergy performance and performance evaluation criteria – conducted during this research successfully identified demonstrates that if the high porosity of all PCL structures decrease to 92%, the best thermal-hydraulic performance is provided. Overall, according to the obtained outcomes, the trussed FETHX with the advantages of using BCCZ lattice structure at 92% porosity presents good thermal-hydraulic performance enhancement among all the investigated PCL structures.

To the best of the authors’ knowledge, this paper is one of the first in the literature that provides thorough thermal-hydraulic characteristics of a novel trussed FETHX with high-porosity PCL structures.

This study aims to analyze the factors, evaluation techniques of the durability of existing railway engineering.

China has built a railway network of over 150,000 km. Ensuring the safety of the existing railway engineering is of great significance for maintaining normal railway operation order. However, railway engineering is a strip structure that crosses multiple complex environments. And railway engineering will withstand high-frequency impact loads from trains. The above factors have led to differences in the deterioration characteristics and maintenance strategies of railway engineering compared to conventional concrete structures. Therefore, it is very important to analyze the key factors that affect the durability of railway structures and propose technologies for durability evaluation.

The factors that affect the durability and reliability of railway engineering are mainly divided into three categories: material factors, environmental factors and load factors. Among them, material factors also include influencing factors, such as raw materials, mix proportions and so on. Environmental factors vary depending on the service environment of railway engineering, and the durability and deterioration of concrete have different failure mechanisms. Load factors include static load and train dynamic load. The on-site rapid detection methods for five common diseases in railway engineering are also proposed in this paper. These methods can quickly evaluate the durability of existing railway engineering concrete.

The research can provide some new evaluation techniques and methods for the durability of existing railway engineering.

The Gulf Cooperation Council (GCC) of countries has some of the highest electricity consumptions and carbon dioxide emissions per capita in the world. This poses a direct challenge to the GCC government’s ability to meet their CO₂ reduction targets. In this review paper the current household electricity consumption situation in the GCC is reviewed.

Three scenarios for reducing energy consumption and CO₂ emissions are proposed and evaluated using strengths, weaknesses, opportunities and threats (SWOT) as well as the political, economic, social, technical, legal and environmental (PESTLE) frameworks.

The first scenario found that using solar Photovoltaic (PV) or hybrid solar PV and wind system to power household lighting could save significant amounts of energy, based on lighting making up between 8% to 30% of electricity consumption in GCC households. The second scenario considers replacement of conventional appliances with energy-efficient ones that use around 20% less energy. The third scenario looks at influencing consumer behavior towards sustainable energy consumption.

Pilot trials of these scenarios are recommended for a number of households. Then the results and feedback could be used to launch the schemes GCC-wide.

The proposed scenarios are designed to encourage responsible electricity consumption and production within households (SDG12).

All three proposals are found viable for policymakers to implement. However, to ensure successful implementation GCC Governments are recommended to review all the opportunities and challenges associated with these schemes as laid out in this paper.

Combining sensory evaluations and hypothetical valuation mechanisms, this study aims to investigate the impact of consumers' product sensory attributes on willingness to pay (WTP) and overall liking for a new apple cultivar.

A sample of non-expert participants (n = 122) evaluated the overall liking and just-about-right (JAR) attributes. A variable transformation approach was applied to make linear and interval regression models between the JAR attributes, overall liking scores and participants' WTP.

The study reveals the high consumer appreciation for the new apple in both hedonic and economic terms. After controlling the anchoring effect's bias, the predicted mean WTP for the new apple cultivar was €3.26 per kilogramme. Crunchiness and flavour significantly affect both participants' overall liking and WTP.

The main limitation is the non-probabilistic sampling procedure, which does not allow for the generalisation of the results. Penalty analysis for JAR attributes in monetary and hedonic terms is beneficial for optimising the product and evaluating its potential in the marketplace.

The findings provide helpful directions for product optimisation in future breeding programmes to ensure the long-term sustainability of the new apple cultivars in the marketplace.

This study provides evidence of the beneficial synergy of mixing sensory-oriented research with the behavioural economics field of study.

This paper aims to analyze the benefits of the blockchain to the circular economy (CE), which is composed of both closed-loop supply chain (CLSC) systems and reverse omnichannel solutions. By ensuring transparency, traceability, visibility and security, the blockchain allows firms to acquire operational capabilities through a CLSC and service capabilities through a reverse omnichannel, which can boost business performance considerably. The related network of relationships can be reinforced by establishing incentives, which entail both smart contracts in the blockchain and active return approaches in CE.

After identifying the boundaries of the theoretical framework, several research hypotheses are developed according to the literature review and emerging gaps. These gaps link to the impact of the blockchain on CE systems (CLSC and reverse omnichannel), as well as the influence on business performance. The hypotheses are then tested using structural equation modeling and adopting a partial least squares-path modeling technique on a dataset composed of 157 firms. Finally, multigroup analysis is used to test the impact of incentives on the research hypotheses.

The blockchain facilitates a more efficient CE system, although reverse omnichannel solutions seldom bring any benefits to performance. The shift from a passive to an active return approach must be carefully evaluated. The CLSC network can benefit from an active return approach by developing appealing incentives for collectors and enhancing the positive effects of the blockchain. In contrast, consumer incentives can have detrimental effects on the blockchain. Various combinations of incentives can only bring a few business performance increases, while collector incentives are vital to reinforce the CE system's operational and service capabilities.

This paper takes a new approach toward the study of CE, which considers a dual circular system composed of a CLSC and a reverse omnichannel. The research explores whether the adoption of blockchain technology enables better return processes by improving the operations in CLSC and services in reverse omnichannel. Finally, this is the first empirical work to evaluate the benefits emerging from incentives, which can activate smart contracts in the blockchain and enable active return approaches in CE.

We read and hear frequently about the role of vision in leadership. Standards for leadership education programs typically emphasize vision as a core component of leadership education and published accounts of successful leadership usually extol the leader’s vision. Given the prevalence of this term in discourse on leadership, it is surprising how little literature exists with specific discussions of how to teach it. In this article I discuss the potential of problem-based pedagogy for teaching the concept of vision. This paper draws on literature, theory, and my professional experience as a faculty member for 20 years in a graduate-level education leadership program.

The remarkable increase of sophistication of artificial intelligence in recent years has already led to its widespread use in martial applications, the potential of so-called “killer robots” ceasing to be a subject of fiction. The purpose of this paper is to re-examine the consequences of the availability of lethal autonomous robots (LARs) on global peace.

Virtually without exception, the aforementioned potential of LARs has generated fear, as evidenced by a mounting number of academic articles calling for the ban on their development and deployment. An analysis of the existing ethical objections to LARs is used as a vehicle for their critique and the advancement of an alternative.

The presented analysis shows the contemporary thought to be deficient in philosophical rigour, these deficiencies leading to a different view, one favourable to the development of LARs.

The emergent thesis is that LARs can in fact be a force for peace, leading to fewer and less deadly wars.