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Thermal conduction anisotropy, which is defined by the dependency of thermal conductivity on direction, is an important parameter in many engineering and research studies such as the design of nuclear waste depositional sites. In this context, the authors aim to investigate the effect of grain shape in thermal conduction anisotropy using pore scale modeling that utilizes real shapes of grains, pores and throats to characterize petrophysical properties of a porous medium.

The authors generalize the swelling circle approach to generate porous media composed of randomly arranged but regularly oriented elliptical grains at various grain ratios and porosities. Unlike previous studies that use fitting parameters to capture the effect of grain–grain thermal contact resistance, the authors apply roughness to grains’ surface. The authors utilize Lattice Boltzmann method to solve steady state heat conduction through medium.

Based on the results, when the temperature field is not parallel to either major or minor axes of grains, the overall heat flux vector makes a “deviation angle” with the temperature field. Deviation angle increases by augmenting the ratio of thermal conductivities of solid to fluid and the aspect ratios of grains. In addition, the authors show that porosity and surface roughness can considerably change the anisotropic properties of a porous medium whose grains are elliptical in shape.

The authors developed an algorithm for generation of non-circular-based porous medium with a novel approach to include grain surface roughness. In previous studies, the effect of grain contacts has been simulated using fitting parameters, whereas in this work, the authors impose the roughness based on the its fractal geometry.

Due to the coronavirus disease 2019 (COVID-19) pandemic, the world faces different issues, and proper healthcare waste (HCW) treatment is one of them. If appropriate disposal of HCW is not performed, it will have hazardous effects on humanity. This paper has identified the significant barriers hindering the proper treatment of healthcare waste management (HCWM) with the strategies to overcome these barriers.

This paper has identified the significant barriers hindering the proper treatment of HCWM with the strategies to overcome these barriers, and different barriers are identified and categorized into organizational, waste handling, human resource and technical barriers. The analytical hierarchy process (AHP) process is used to rank the barriers and sub-barriers. Then, the Fuzzy Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) method evaluates the strategies for proper implementation of HCWM.

The results show that organizational barriers are the most significant barrier, with a lack of coordination of hospitals with other authorities and no priority given to waste management issues as highly ranked barriers. The results of the Fuzzy TOPSIS method indicate that “Increase govt support and policies” and “Enhance training and awareness of employees” are the most feasible strategies to overcome these barriers for the successful implementation of HCWM.

This study will be helpful in policy formulations for the proper treatment of HCW in an efficient manner. This paper helps to complete the research gap by providing the different characteristics of barriers.

This paper fills the research gap by expanding the limited knowledge in this field and providing further evidence on this phenomenon. The study also enables the distinctive characteristics of barriers to be understood within a particular context.

Present study aims to extend the lattice Boltzmann method (LBM) to simulate radiation in geometries with curved boundaries, as the first step to simulate radiation in complex porous media. In recent years, researchers have increasingly explored the use of porous media to improve the heat transfer processes. The lattice Boltzmann method (LBM) is one of the most effective techniques for simulating heat transfer in such media. However, the application of the LBM to study radiation in complex geometries that contain curved boundaries, as found in many porous media, has been limited.

The numerical evaluation of the effect of the radiation-conduction parameter and extinction coefficient on temperature and incident radiation distributions demonstrates that the proposed LBM algorithm provides highly accurate results across all cases, compared to those found in the literature or those obtained using the finite volume method (FVM) with the discrete ordinates method (DOM) for radiative information.

For the case with a conduction-radiation parameter equal to 0.01, the maximum relative error is 1.9% in predicting temperature along vertical central line. The accuracy improves with an increase in the conduction-radiation parameter. Furthermore, the comparison between computational performances of two approaches reveals that the LBM-LBM approach performs significantly faster than the FVM-DOM solver.

The difficulty of radiative modeling in combined problems involving irregular boundaries has led to alternative approaches that generally increase the computational expense to obtain necessary radiative details. To address the limitations of existing methods, this study presents a new approach involving a coupled lattice Boltzmann and first-order blocked-off technique to efficiently model conductive-radiative heat transfer in complex geometries with participating media. This algorithm has been developed using the parallel lattice Boltzmann solver.

The study aims to find the synchronization between foreign agriculture investment (FAI) and Sustainable Development Goals (SDGs) related to agriculture as classified by the Food and Agriculture Organization (FAO). The study tries to find such an association in India over 2 decades from 2001.

The Toda-Yamamoto Granger using the M-Wald test for the non-causality procedure is applied to find the synchronization. Stationarity is tested using the Augmented Dickey-Fuller, Phillips-Perron and Kwiatkowski, Phillips, Schmidt and Shin (KPSS) tests. The Johanson methodology with MacKinnon-Haug-Michelis P-value is employed for the Cointegration test.

The empirical results indicate that the FAI Granger cause SDG2 “Zero hunger” and “Overall sustainability”, but SDG13 “Climate Change”, SDG6 “Clean water and sanitation”, SDG12 “Responsible production and consumption” and SDG15 “Life on Land” granger cause global investments. Notwithstanding, SDG5 “Gender equality” and SDG14 “Life below water” found no-way causality with FAI.

Host governments should prioritize sector-level sustainable development, notably agricultural SDGs, to attract global investments. Foreign agriculture investment is influenced differently by various SDGs; thus, policymakers should concentrate on specific agricultural SDGs to enhance the flow of capital into the agriculture sector. Global investors should take sustainability into account while framing foreign investment plans, and the supra-national organization may consider global agricultural investments while addressing the problems related to global food security.

The distinguishing feature of the study is that SDGs classified by the FAO from a global investment perspective have not been studied so far.

This paper aims to understand the difficulties faced by Latin American oil and gas (O&G) companies in adopting integrated practices aligned with the UN Sustainable Development Goals (SDG) Agenda.

A Delphi study was conducted with 14 experts with extensive knowledge and experience in the O&G sector to collect opinions and investigate sustainable practices in the Latin American context.

A consensus was reached after two rounds, demonstrating a unified view of sustainability experts on the difficulties faced by O&G companies to adopt practices aligned with the SDGs. The difficulties identified through the Delphi method were allocated into five clusters named: “public sector and governments,” “civil society,” “corporate issues,” “technology and innovation” and “financial aspects.” These clusters were used to discuss the main challenges associated with implementing business practices that recognize the SDGs and their achievement as a synergistic reinforcing system rather than an additive structure.

This study provides further insights into the underexplored subject relating to the challenges experienced by Latin American O&G companies in the implementation of the SDGs, adopting the perspective of academic and industry experts in this field. The findings can help professionals in O&G companies implement sustainable practices, policymakers in debates about futures laws and regulations and academic in future research.

Using panel data for the Regional Comprehensive Economic Partnership (RCEP) member states, the present study explored the role of RCEP negotiations on tourism development.

A dynamic econometric model, namely the panel autoregressive dynamic lag model (PARDL) has been used. To test for panel causality, Dumitrescu–Hurlin panel causality tests were used.

Through the use of a dynamic econometric model, namely the PARDL, the results show that the RCEP negotiations, growth rates, as well as international trade contribute towards tourism development. Furthermore, the Dumitrescu–Hurlin panel causality tests confirm the existence of a bidirectional causal link between tourism development and RCEP negotiations. Finally, a unidirectional causal link is observed between tourism development and international trade.

This existing evidence on the topic seems to be very scant and limited to specific regions and particular regional trade agreements. This paper thus fills an important gap in the literature by advancing evidence about the effects of the RCEP on international tourism flows across member countries.

This study aims to introduce a metal porous burner design. Literature is surveyed in a comprehensive manner to relate the current design with ongoing research. A demonstrative computational fluid dynamics (CFD) analysis is presented with projected flow conditions by means of a common commercial CFD code and turbulence model to show the flow-related features of the proposed burner. The porous metal burner has a novel design, and it is not commercially available.

Based on the field experience about porous burners, a metal, cylindrical, two-staged, homogenous porous burner was designed. Literature was surveyed to lay out research aspects for the porous burners and porous media. Three dimensional solid computer model of the burner was created. The flow domain was extracted from the solid model to use in CFD analysis. A commercial computational fluid dynamics code was utilized to analyze the flow domain. Projected flow conditions for the burner were applied to the CFD code. Results were evaluated in terms of homogenous flow distribution at the outer surface and flow mixing. Quantitative results are gathered and are presented in the present report by means of contour maps.

There aren’t any flow sourced anomalies in the flow domain which would cause an inefficient combustion for the application. An accumulation of gas is evident around the top flange of the burner leading to higher static pressure. Generally, very low pressure drop throughout the proposed burner geometry is found which is regarded as an advantage for burners. About 0.63 Pa static pressure increase is realized on the flange surface due to the accumulation of the gas. The passage between inner and outer volumes has a high impact on the total pressure and leads to about 0.5 Pa pressure drop. About 0.03 J/kg turbulent kinetic energy can be viewed as the highest amount. Together with the increase in total enthalpy, total amount of energy drawn from the flow is 0.05 J/kg. More than half of it spent through turbulence and remaining is dissipated as heat. Outflow from burner surface can be regarded homogenous though the top part has slightly higher outflow. This can be changed by gradually increasing pore sizes toward inlet direction.

Combustion via a porous medium is a complex phenomenon since it involves multiple phases, combustion chemistry, complex pore geometries and fast transient responses. Therefore, experimentation is used mostly. To do a precise computational analysis, strong computational power, parallelizing, elaborate solid modeling, very fine meshes and small time steps and multiple models are required.

Findings in the present work imply that a homogenous gas outflow can be attained through the burner surfaces while very small pressure drop occurs leading to less pumping power requirement which is regarded as an advantage. Flow mixing is realizable since turbulent kinetic energy is distinguished at the interface surface between inner and outer volumes. The porous metal matrix burner offers fluid mixing and therefore better combustion efficiency. The proposed dimensions are found appropriate for real-world application.

Conducted analysis is for a novel burner design. There are opportunities both for scientific and commercial fields.

This study’s goal is to research and describe developing green technology and green business models, as well as their commercial advantages. However, it focuses on how old business breakthroughs and models may be transformed into new green technologies and innovations that can affect the global business environment. This research concentrates on the technology component of green technologies and provides information on a variety of relevant emerging green business models and innovations such as energy efficiency, renewable energy consumption, commodities and systems, environmental protection, nontoxic materials, and waste minimization, among others. Additionally, this research connects Emerging Green Technology (EGT) innovations to the business for sustainability. It also emphasizes the advantages of green technology adoption in business specially in developing economies.

For that purpose, a Systematic Literature Review (SLR) was performed based on the “inclusion/exclusion criteria” and “PRISMA flow diagram method”. The first screening and quality evaluation rejected 67 publications, 8 in eligibility and 10 in credibility. In the subsequent round, 45 papers out of 210 that met the search parameters were included to access the findings.

This study provides a foundation for future research into sustainable economic potential by examining the development, breakthroughs, obstacles, future trends and new research prospects of EGTs. As such, this research will serve as a helpful resource for economically growing nations looking to foster long-term growth in their businesses through sustainable development strategies.

The first limitation of the study is the generalization of the findings. The sample size of the study is limited. For that purpose, an SLR and “PRISMA flow diagram” methods were performed by “inclusion/exclusion criteria” for literature review. Except these, there are many new techniques of SLR. Further research with more sampling and sophisticated tests could produce better results for this study.

This research provides valuable insights for businesses and politicians seeking to protect the environment, promote economic growth and create a sustainable society. The findings will be particularly useful for emerging nations grappling with issues related to technical innovation, safe environmental practices, reliable renewable energy sources, and ecological and economic growth.

This study’s findings will aid in the design and implementation of new green technology and innovations in current businesses, which will assist in limiting climate change and eventually affect their move to sustainable growth paradigms. For emerging nations, this study will be useful in addressing issues about technical innovation, safe environmental conditions, reliable renewable energy sources as well as ecological and economic growth. According to our research results, the authorities of developing nations would gain from utilizing green business models and technology to spur economic development. Our findings should thus add to the current body of knowledge.

Emerging economies have been highlighted as an important growth source of the global economy. However, this group of countries has not received enough academic attention yet. Therefore, this study aims to identify the impact of research and development (R&D) expenditure on economic growth in emerging economies.

The theoretical framework of the production function is applied to quantitatively analyse the impact of R&D expenditure on economic growth with a sample of 29 emerging economies in the period between 1996 and 2019.

The panel cointegration test confirms the existence of long-run cointegration relationships between economic growth and independent variables in these emerging economies. Besides, the estimated results show that the national R&D expenditure has positive effects on economic growth from both direct and interaction dimensions. This evidence has filled the empirical research gap in the R&D-growth nexus in the case of emerging economies. Finally, while gross capital and education have positive impacts on growth, corruption has a harmful effect on economic growth in these countries.

The results highlight that policymakers should enhance R&D expenditure and R&D activities as the key national development strategy. The investment in R&D not only helps emerging economies avoid the middle-income trap but also pushes these countries to successfully join the group of developed countries.

To the best of the authors’ knowledge, this research is among the first to examine the impact of R&D expenditure on economic growth with a homogeneous sample of emerging economies. The results are obviously helpful for policymakers to use R&D as the key development strategy for supporting economic growth in emerging economies in the future.

One key issue of maintaining Web information systems is to guarantee the consistency of their knowledge base, in particular, the rules governing them. There are currently few methods that can ensure that rule bases management can scale to the amount of knowledge in these systems environment.

In this paper, the authors propose a method to detect correct dependencies between rules. This work represents a preliminary step for a proposal to eliminate rule base anomalies. The authors previously developed a method that aimed to ameliorate the extraction of rules dependency relationships using a new technique. In this paper, they extend the proposal with other techniques to increase the number of extracted rules dependency relationships. The authors also add some modules to filter and represent them.

The authors evaluated their own method against other semantic methods. The results show that this work succeeded in extracting better numbers of correct rules dependency relationships. They also noticed that the rule groups deduced from this method’s results are very close to those provided by the rule bases developers.

This work can be applied to knowledge bases that include a fact base and a rule base. In addition, it is independent of the field of application.