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The purpose of this article is the propagation of Rayleigh waves in a homogeneous, isotropic, initially stressed orthotropic elastic solid half-space lying under a homogeneous, viscous, inviscid liquid layer of finite thickness.

In the presence of both viscous and inviscid liquids, it derives the phase velocity, initial stress, and wave number-dependent frequency equation for an orthotropic elastic solid. With the help of the MATLAB program, the thickness effects of liquid layers, initial stress, and viscosity on the phase velocity and attenuation coefficient of the Rayleigh wave are explained for a particular model.

The phase velocity-dependent dispersion relation of Rayleigh waves at the interface of viscous liquid and solid half-space is a function of initial stress and wave number. Rayleigh waves along the free surface of an orthotropic elastic half-space are also derived as a particular case. The classical results of an inviscid liquid are achieved when the thickness of a viscous liquid approaches zero. Well-known classical results for initially stressed orthotropic elastic solids were also derived.

So far, many researchers have looked into the propagation of surface waves at the interfaces of solid–inviscid liquid, solid–solid, and multilayer interfaces. But in this article, the dispersion behavior of Rayleigh wave propagation in an initially stressed homogeneous orthotropic elastic solid half-space under a double layer of viscous liquid and inviscid liquid is studied.

The purpose of this research contribution is to examine the thermoelastic interactions in a fiber-reinforced thermoelastic medium under the action of initial stress and gravity in which, the conventional Fourier’s law is modified, introducing a thermal relaxation parameter in the GN-III model of generalized thermoelasticity.

The work presented in this manuscript proposes a thermoelastic problem where the Moore–Gibson–Thompson equation is used to model the thermal law. The technique of normal mode is employed to derive the exact expressions of various physical fields under consideration.

Under the application of moving thermal load, normal displacement, temperature distribution and stress components are calculated numerically with the help of MATLAB software and then presented graphically to support the theoretical formulation.

Field variables are affected by initial stress, gravity, fiber reinforcement, velocity of thermal load and time duration, according to numerical simulations. Some particular cases of interest have also been inferred from the present problem.

Studying the shear stress and pressure resulting on the walls of blood vessels, especially during high-pressure cases, which may lead to the explosion or rupture of these vessels, can also lead to the death of many patients. Therefore, it was necessary to try to control the shear and normal stresses on these veins through nanoparticles in the presence of some external forces, such as exposure to some electromagnetic shocks, to reduce the risk of high pressure and stress on those blood vessels. This study aims to examines the shear and normal stresses of electroosmotic-magnetized Sutterby Buongiorno’s nanofluid in a symmetric peristaltic channel with a moderate Reynolds number and curvature. The production of thermal radiation is also considered. Sutterby nanofluids equations of motion, energy equation, nanoparticles concentration, induced magnetic field and electric potential are calculated without approximation using small and long wavelengths with moderate Reynolds numbers.

The Adomian decomposition method solves the nonlinear partial differential equations with related boundary conditions. Graphs and tables show flow features and biophysical factors like shear and normal stresses.

This study found that when curvature and a moderate Reynolds number are present, the non-Newtonian Sutterby fluid raises shear stress across all domains due to velocity decay, resulting in high shear stress. Additionally, modest mobility increases shear stress across all channel domains. The Sutterby parameter causes fluid motion resistance, which results in low energy generation and a decrease in the temperature distribution.

Equations of motion, energy equation, nanoparticle concentration, induced magnetic field and electric potential for Sutterby nano-fluids are obtained without any approximation i.e. the authors take small and long wavelengths and also moderate Reynolds numbers.

Many industries use non-Newtonian ternary hybrid nanofluids (THNF) because of how well they control rheological and heat transport. This being the case, this paper aims to numerically study the Casson-Williamson THNF flow over a yawed cylinder, considering the effects of several slips and an inclined magnetic field. The THNF comprises Al₂O₃-TiO₂-SiO₂ nanoparticles because they improve heat transmission due to large thermal conductivity.

Applying suitable nonsimilarity variables transforms the coupled highly dimensional nonlinear partial differential equations (PDEs) into a system of nondimensional PDEs. To accomplish the goal of achieving the solution, an implicit finite difference approach is used in conjunction with Quasilinearization. With the assistance of a script written in MATLAB, the numerical results and the graphical representation of those solutions were ascertained.

As the Casson parameter β increases, there is an improvement in the velocity profiles in both chord and span orientations, while the gradients Re1/2Cf, Re1/2C¯f reduce for the same variations of β. The velocities of Casson THNF are greater than those of Casson-Williamson THNF. Approximately, a 202% and a 32% ascension are remarked in the magnitudes of Re1/2Cf and Re1/2C¯f for Casson-Williamson THNF than the Casson THNF only. When velocity slip attribute S1 jumps to 1 from 0.5, magnitude of both F(ξ,η) and Re1/2Cf fell down and it is reflected to be 396% at ξ=1, Wi=1 and β=1. An augmentation in thermal jump results in advanced fluid temperature and lower Re−1/2Nu. In particular, about 159% of down drift is detected when S2 taking 1.

There is no existing research on the effects of Casson-Williamson THNF flow over a yawed cylinder with multiple slips and an angled magnetic field, according to the literature.

The particle distribution in a fluid is mostly not homogeneous. The inhomogeneous dispersion of solid particles affects the velocity profile as well as the heat transfer of fluid. This study aims to highlight the effects of varying density of particles in a fluid. The fluid flows through a wavy curved passage under an applied magnetic field. Heat transfer is discussed with variable thermal conductivity.

The mathematical model of the problem consists of coupled differential equations, simplified using stream functions. The results of the time flow rate for fluid and solid granules have been derived numerically.

The fluid and dust particle velocity profiles are being presented graphically to analyze the effects of density of solid particles, magnetohydrodynamics, curvature and slip parameters. Heat transfer analysis is also performed for magnetic parameter, density of dust particles, variable thermal conductivity, slip parameter and curvature. As the number of particles in the fluid increases, heat conduction becomes slow through the fluid. Increase in temperature distribution is noticed as variable thermal conductivity parameter grows. The discussion of variable thermal conductivity is of great concern as many biological treatments and optimization of thermal energy storage system’s performance require precise measurement of a heat transfer fluid’s thermal conductivity.

This study of heat transfer with inhomogeneous distribution of the particles in a fluid has not yet been reported.

The purpose of this study is to examine the state of the literature related to the psychophysiological effects of travel, to identify gaps in the literature and to propose a vision to guide research between now and 2050.

The study was guided by a systematic literature review which started with more than 2,100 papers. The extant review and its findings are written in a conceptual nature with the concluding propositions, for the year 2050, guided by the systematic review and the authors’ personal knowledge.

It was found that research related to the psychophysiological effects of travel has greatly progressed over the past two decades. Findings include evidence that travel reduces both perceived and actual stresses and that taking more vacations has the ability to make people healthier. The study also revealed that travel can have negative effects on physiological health. The overall results led to a call for research on the psychophysiological benefits of travel between now and 2050.

The systematic review of literature was limited to studies conducted in English and to studies that included the words “travel” or “tourism” and “benefits”, stress, “health” and “wellness”. Results provide a discussion of theories that should guide the research agenda.

The review and proposed vision for research provide a detailed guide for researchers to follow. Should the proposed research come to fruition, tourism practitioners globally will have results to aid in engineering tourism experiences that could provide health benefits to visitors.

The proposed vision could have profound social implications, as the understanding of the positive and negative effects of travel should make travel experiences healthier for all. The study also proposes a call for research to determine ways to make the benefits of travel available to both the “haves” and “have nots” so that the benefits of travel can be more inclusive.

The main contribution of this manuscript is that it proposes 11 propositions for research between now and 2050 based on a thorough review of gaps related to the psychophysiological benefits of travel. The resultant propositions provide a clear and unique call for research in this area of inquiry.

本研究的主要目标是检查与旅行的心理生理益处相关的文献状况, 找出文献中的空白, 并提出从现在到2050年指导研究的愿景。

这项研究以一项系统的文献综述为指导, 该综述从2100多篇论文开始。现有的综述及其研究结果是在系统综述和作者个人知识的指导下, 以概念性的形式撰写的, 并附有2050年的结论性命题。

研究发现, 在过去的二十年里, 与旅行的心理生理益处相关的研究取得了长足的进步。研究结果包括有证据表明, 旅行可以减轻感知和实际的压力, 多度假可以使人们更健康。该研究还表明, 旅行会对生理健康产生负面影响。总体结果促使人们呼吁研究从现在到2050年旅行的心理生理益处。

本文的主要贡献是, 它根据对旅行的心理生理益处相关差距的全面回顾, 提出了从现在到2050年的11个研究主题。由此产生的主题为这一研究领域的研究提供了明确而独特的呼吁。

Los objetivos principales del presente estudio eran examinar el estado de la literatura relacionada con los beneficios psicofisiológicos de los viajes, identificar lagunas en la bibliografía y proponer una visión que guíe la investigación de aquí a 2050.

El estudio se guió por una revisión bibliográfica sistemática que partió de más de 2.100 artículos. La revisión existente y sus hallazgos están redactados de forma conceptual con las proposiciones finales para el año 2050, guiadas por la revisión sistemática y el conocimiento personal de los autores.

Se encontró que la investigación relacionada con los beneficios psicofisiológicos de los viajes ha progresado mucho en las dos últimas décadas. Resultados incluyen pruebas de que viajar reduce tanto el estrés percibido como el real y de que tomar más vacaciones tiene la capacidad de hacer que las personas estén más sanas. El estudio también reveló que viajar puede tener efectos negativos sobre la salud fisiológica. Los resultados globales condujeron a una llamada a la investigación sobre los beneficios psicofisiológicos de los viajes de aquí a 2050.

La principal aportación de este manuscrito es que propone once proposiciones para la investigación de aquí a 2050 basadas en una revisión exhaustiva de las lagunas relacionadas con los beneficios psicofisiológicos de los viajes. Las proposiciones resultantes constituyen un llamamiento claro y único a la investigación en este ámbito de estudio.

In recent times, ternary hybrid nanofluid has garnered attention from scientist and researchers due to its improved thermal efficiency. This study aims to delve into the examination of ternary hybrid nanofluid (Al₂O₃–Cu–TiO₂/water), particularly concerning axisymmetric flow over a nonlinearly permeable stretching/shrinking disk. In addition, the investigation of convective boundary conditions and thermal radiation effects is also considered within the context of the described flow problem.

Mathematical formulations representing this problem are reduced into a set of ordinary differential equations (ODEs) using similarity transformation. The MATLAB boundary value problem solver is then used to solve the obtained set of ODEs. The impact of considered physical parameters such as suction parameter, radiation parameter, nonlinear parameter, nanoparticle volumetric concentration and Biot number on the flow profiles as well as the physical quantities is illustrated in graphical form.

The findings revealed the thermal flux for the nonlinearly shrinking disk is approximately 1.33%, significantly higher when compared to the linearly shrinking disk. Moreover, the existence of dual solutions attributed to the nonlinear stretching/shrinking disk is unveiled, with the first solution being identified as the stable and reliable solution through temporal stability analysis.

Understanding ternary hybrid nanofluid behavior and flow has applications in engineering, energy systems and materials research. This study may help develop and optimize nanofluid systems like heat exchangers and cooling systems.

The study of flow dynamics across nonlinear stretching/shrinking disk gains less attention compared to linear stretching/shrinking geometries. Many natural and industrial processes involve nonlinear changes in boundary shapes or sizes. Understanding flow dynamics over nonlinear shrinking/stretching disks is therefore essential for applications in various fields such as materials processing, biomedical engineering and environmental sciences. Hence, this study highlights the axisymmetric flow over a nonlinear stretching/shrinking disk using ternary hybrid nanofluid composed of alumina (Al₂O₃), copper (Cu) and titania (TiO₂). Besides, this study tackles a complex problem involving multiple factors such as suction, radiation and convective boundary conditions. Analyzing such complex systems can provide valuable insights into real-world phenomena where multiple factors interact.

This paper aims to synthesize 6-ethyl-4-hydroxyquinolin-2(1H)-one as a new enol-type coupling component in the preparation of some 3-arylazo-4-hydroxyquinolin-2(1H)-one dyes and evaluate the solvent effects on their absorption in ultraviolet-visible spectra.

6-Ethyl-4-hydroxyquinolin-2(1H)-one was synthesized by thermal cyclocondensation reaction of N, N′-bis(4-ethylphenyl) malonamide at 130–140°C in polyphosphoric acid. This compound was then applied in the azo-coupling reaction with some aniline-based diazonium salts, so as to prepare seven new mono-heterocyclic azo dyes. The structures of the compounds were confirmed using mass spectroscopic technique. Fourier transform infra red (FT-IR) and 1H proton nuclear magnetic resonance (1H NMR) and carbon-13 nuclear magnetic resonance (13 C NMR) studies on the structure of the azo compounds revealed that they exist as two E- and Z-isomers of hydrazone tautomer both in solid and solution state. The effects of acid and base on the visible absorption spectra of the dyes were also evaluated and discussed.

Ultra violet-visible UV-vis absorption spectra of the dyes didn’t show significant variation by changing of solvents because of intramolecular H-bonding between proposed hydrazone forms and 2- and 4-keto functions in their structures. The spectra of the dyes were not sensitive to the addition of acid but were very sensitive to base.

The synthesized 3-arylazo-4-hydroxyquinolin-2(1H)-one dyes are new members in the 4-hydroxyquinolin-2(1H)-one azo dyes family, where very few details regarding the synthesis of such dyes are reported before in the literature. They are unique in terms of synthesis and spectral properties.

Just-in-Time (JIT) arrival in the context of port calls can be used to reduce fuel and emissions to achieve environmental targets. The purpose of this paper is to study the implementation process of the Pre-booking Berth Allocation Policy (PBP) and analyze the effectiveness of this policy for the implementation of JIT in port calls.

The study deploys a single case study approach to empirically analyze port authority’s transition from a first-come-first-served (FCFS) arrival policy to the PBP. Observations, interviews and documents were used to collect data during 2020–2022. The analysis deployed the capability, opportunity, motivation and behavior model.

The transition from FCFS to PBP requires an inter-organizational approach, engaging external actors to manage diverse needs and preferences. This fosters effective transition and addresses conflicting interests. The PBP enables JIT arrival, enhancing operational and environmental performance, but faces barriers such as resource dependency and lack of trust. Information sharing capability among the actors, supported by Port Community Systems and adjusted operating rules, is crucial. Moreover, the PBP facilitates integration between sea and hinterland transportation, improving planning and efficiency across maritime transportation chains.

The single case study limits the generalizability of the findings.

Implementing the PBP is complex and demands careful planning from managers. Involving port call actors in the transition is helpful for port managers because they provide valuable feedback and highlight overlooked issues.

Five propositions are suggested to highlight the role of inter-organizational collaboration, information sharing and overcoming barriers such as resource dependency to successfully realize the benefits of JIT in maritime transportation chains.

Located at the confluence of the White and Blue Niles, in the core of Sudan’s capital, the small island of Tuti has been affected by flooding events throughout its history. To protect it, the Tuti people (Tawatas) developed the Taya, a traditional early warning, community-based flood management system. However, several challenges, including climate change impacts, demographic variations, a fluctuating economy and, more recently, an ongoing armed conflict, are increasing the risks associated with the annual flooding, threatening this traditional knowledge and other local community practices.

In the framework of International Centre for the Study of the Preservation and Restoration of Cultural Property (ICCROM)’s Net Zero: Heritage for Climate Action project Tuti Island was presented as an innovation site, aiming to deepen on Tuti’s traditional knowledge as an efficient heritage-based adaptation strategy to reduce the impacts of climate change. Unfortunately, the implementation of the project faced more challenges and constraints than initially foreseen when the conflict broke out in the capital of Sudan in April 2023. The project activities, methodology and approach had to be redesigned in light of the new situation.

The Taya traditional system plays a key role in reducing vulnerabilities and enhancing the community’s capacity to address the impacts of climate change, as well as to cope with other crises, including armed conflict, due to its deep connection with the Tawata’s identity.

The project, which was originally planned to focus on climate action through heritage, became a representative case of the disaster–conflict nexus, reminding us that overlapping crises may occur in the same area, putting additional pressure on the population, their cultural heritage and the measures to tackle specific issues.