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The purpose of this paper is to introduce a spectral model capable of simulating fully transient conductive‐convective heat transfer processes in an axially‐symmetric shallow geothermal system consisting of a borehole heat exchanger embedded in a soil mass.

The proposed model combines the exactness of the analytical methods with important extent of generality in describing the geometry and boundary conditions of the numerical methods. It calculates the temperature distribution in all involved borehole heat exchanger components and the surrounding soil mass using the discrete Fourier transform, for the time domain, and the Fourier‐Bessel series, for the spatial domain.

The paper calculates the temperature distribution in all involved borehole heat exchanger components and the surrounding soil mass in a robust and computationally very efficient procedures. Analysis which might take long time in a work station, if use is made of standard numerical procedures, takes only 1 second in an Intel PC with the proposed model.

The model is capable of simulating fully transient heat transfer in a shallow geothermal system subjected to short and long‐term time varying boundary conditions. The CPU time for calculating temperature distributions in all involved components; pipe‐in, pipe‐out, grout, and soil, using 2048 FFT samples, for the time domain, and 100 Fourier‐Bessel series samples, for the spatial domain, was in the order of 1 second in an Intel PC. The accuracy and computational efficiency of the model makes it, if elaborated, vital for engineering practice.

The proposed model is original and generic. The idea behind it is new and has not been utilized in this field of application. The model can be extended easily to include other types of borehole heat exchangers embedded in multi‐layer systems.

This paper aims to present a framework for deriving analytical and semi‐numerical models for coupled conductive‐convective heat transfer processes in a borehole heat exchanger subjected to general initial and boundary conditions.

The discrete Fourier transform and the spectral element method have been utilized for deriving two spectral models for a single U‐tube borehole heat exchanger in contact with a soil mass.

Verification and numerical examples have shown that the developed models are accurate and computationally very efficient. It is illustrated that one spectral element is capable of producing results which are more accurate than those produced by 200 finite elements.

The gained computational efficiency and accuracy will boost considerably the possibilities for more insight into geothermal analysis, which will improve the procedure for designing competitive energy extraction systems.

The models are capable of calculating exactly the temperature distribution in all involved borehole heat exchanger components and their thermal interactions.

This paper aims to present a computationally efficient finite element model for the simulation of isothermal immiscible two-phase flow in a rigid porous media with a particular application to CO₂ sequestration in underground formations. Focus is placed on developing a numerical procedure, which is effectively mesh-independent and suitable to problems at regional scales.

The averaging theory is utilized to describe the governing equations of the involved unsaturated multiphase flow. The level-set (LS) method and the extended finite element method (XFEM) are utilized to simulate flow of the CO₂ plume. The LS is employed to trace the plume front. A streamline upwind Petrov-Galerkin method is adopted to stabilize possible occurrence of spurious oscillations due to advection. The XFEM is utilized to model the high gradient in the saturation field front, where the LS function is used for enhancing the weighting and the shape functions.

The capability of the proposed model and its features are evaluated by numerical examples, demonstrating its accuracy, stability and convergence, as well as its advantages over standard and upwind techniques. The study showed that a good combination between a mathematical model and a numerical model enables the simulation of complicated processes occurring in complicated and large geometry using minimal computational efforts.

A new computational model for two-phase flow in porous media is introduced with basic requirements for accuracy, stability, and convergence, which are met using relatively coarse meshes.

Now‐a‐days, logistics research focuses on the ability of logistics to deliver a quality service and generate greater satisfaction with the delivered service. Therefore, the aim of this work is to analyze the quality, satisfaction, and loyalty sequence in the logistic service delivery context, with the purpose of considering the role of information and communication technologies (ICT) in this chain of effects.

After reviewing the different approaches given by the literature, SEM analysis is used to contrast the hypotheses for the analyzed constructs in the presence of high/low ICT level. A questionnaire based on personal survey was conducted among manufacturers. The study collected data from 194 companies. Structural equation modeling was applied to these data to test relationships among the variables in the study.

The reliability and validity tests show satisfactory results. The conclusions confirm this chain of consequences, and emphasize the incidence of ICT in the description and intensity of these relations.

As non‐probabilistic sampling methods have been used, in subsequent research, it would be useful to obtain a more representative population sample. In future, works relations between the variables proposed would be analyzed contemplating the sectoral nature of the sample, accepting that relationship intensity may be modified according to the company's sector of activity.

This paper describes a framework to explore the relationships between service quality, customer satisfaction and loyalty in the supply chain from the perspective of ICT.

This paper aims to examine the opportunities and challenges of using ChatGPT in higher education. Furthermore, it is also discuss the potential risks and plunders of these tools.

The paper discuss the use of artificial intelligence (AI) in academia and explores the opportunities and challenges of using ChatGPT in higher education. It also highlights the difficulties of detecting and preventing academic dishonesty and suggests strategies that universities can adopt to ensure ethical and useful use of these tools.

The paper concludes that while the use of AI tools, ChatGPT in higher education presents both opportunities and challenges. The universities can effectively address these concerns by taking a proactive and ethical approach to the use of these tools. This paper further suggests that universities should develop policies and procedures, provide training and support, to detect and prevent cheating intentions.

The paper provides insights into the opportunities and challenges of using ChatGPT in higher education, as well as strategies for addressing concerns related to academic dishonesty. The paper further adds importance to the discussion on the ethical and responsible use of AI tools in higher education.

The purpose of this study is to analyze the build quality and compression properties of thin-walled 304L honeycomb structures manufactured by selective laser melting. Four honeycomb wall thicknesses, from 0.2 to 0.5 mm, were built and analyzed.

The density of the honeycombs was changed by increasing the wall thickness of each sample. The honeycombs were tested under compression. Differences between the computer-assisted design model and the as-built structure were quantified by measuring physical dimensions. The microstructure was evaluated by optical microscopy, density measurements and microhardness.

The Vickers hardness of the honeycomb structures was 209 ± 14 at 50 g load. The compression ultimate and yield strength of the honeycomb material were shown to increase as the wall thickness of the honeycomb samples increased. The specific ultimate strength also increased with wall thickness, while the specific yield stress of the honeycomb remained stable at 42 ± 2.7 MPa/g/cm³. The specific ultimate strength minimized near 0.45 mm wall thickness at 82 ± 5 MPa/g/cm³ and increased to 134 ± 3 MPa/g/cm³ at 0.6 mm wall thickness.

This study highlights a single lightweight metal structure, the honeycomb, built by additive manufacturing (AM). The honeycomb is an interesting structure because it is a well-known building material in the lightweight structural composites field but is still considered a relatively complex geometric shape to fabricate. As shown here, AM techniques can be used to make complex geometric shapes with strong materials to increase the design flexibility of the lightweight structural component industry.

Honeycomb cellular structures exhibit unique mechanical properties such as high specific strength, high specific stiffness, high energy absorption and good thermal and acoustic performance. This paper aims to use numerical modeling to investigate the effective elastic moduli, in-plane and out-of-plane, for thick-walled honeycombs manufactured using selective laser melting (SLM).

Theoretical predictions were performed using homogenization on a sample scale domain equivalent to the as-manufactured dimensions. A Renishaw AM 250 machine was used to manufacture hexagonal honeycomb samples with wall thicknesses of 0.2 to 0.5 mm and a cell size of 3.97 mm using 304 L steel powder. The SLM-manufactured honeycombs and cylindrical test coupons were tested using flatwise and edgewise compression. Three-dimensional finite element and strain energy homogenization were conducted to determine the effective elastic properties, which were validated by the current experimental outcomes and compared to analytical models from the literature.

Good agreement was found between the results of the effective Young’s moduli ratios numerical modeling and experimental observations. In-plane effective elastic moduli were found to be more sensitive to geometrical irregularity compared to out-of-plane effective moduli, which was confirmed by the analytical models. Also, it was concluded that thick-walled SLM manufactured honeycombs have bending-dominated in-plane compressive behavior and a stretch-dominated out-of-plane compressive behavior, which matched well with the simulation and numerical models predictions.

This work uses three-dimensional finite element and strain energy homogenization to evaluate the effective moduli of SLM manufactured honeycombs.

The purpose of this paper is to investigate the application of water harvesting techniques as a sustainability measure of the cropping system for barley production in the Fa'a farming area located in the Northern part of Jordan.

Usually, the farmers plant barley to feed their animals. The climate of the area is semi‐arid to arid. Annual average rainfall in the area is not enough for the survival of barley and farmers are usually grassing barley instead of harvesting. Overgrazing and mismanagement contribute to land degradation in the area, which affect the production system in the area.

The paper investigates the runoff collection system which is framed with two different sizes in three different land uses: cultivated with barley; fallow and rangeland. Data are collected in all of five stormy events. The total soil sediment is measured for these land uses. The amount of water collected from runoff is also measured for the same areas. The ploughing against the slope with planting barley can reduce the runoff and soil sediment increasing soil moisture and reducing soil erosion. The barley production as biomass is highest using strip cropping as opposed to zero ratio control site or conventional cultivation. The plants' lengths were also higher in strip cropping ranging between 26 and 28 centimetres in the different strip cropping ratios compared to 23 centimetres in the conventional cropping system.

By using the results from this new research to such an area, surface runoff from the uncultivated land can be used to supplement the rainfall to the cultivated land. This increases the share of runoff on the cultivated land to the degree where barley can be harvested.

To provide background and insight into the maintenance of water supplies to Jordan including policy initiatives and solutions.

A case study style examination of recent articles and policy initiatives which provide a practical oversight of the real issues that impact upon Jordanian industry enabling the reader to grasp the significance of the water issue in the country.

Provides information on a variety of solutions to the water problem in Jordan. This paper concludes that water transfer via pipeline is the best solution but does not reach conclusions on the best route.

Not an exhaustive examination and does not reach conclusions concerning an optimum pipeline route.

A useful overview for potential investors and/or facilities managers in the region. Useful as an examination of an extreme regional problem for both academics and practitioners.

Provides information on a region where economic growth is anticipated. Supplies information on water resource problems for industry.