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The purpose of this study is to determine the impact of two-phase power law nanofluid on a curved arterial blood flow under the presence of ovelapped stenosis. Over the past couple of decades, the percentage of deaths associated with blood vessel diseases has risen sharply to nearly one third of all fatalities. For vascular disease to be stopped in its tracks, it is essential to understand the vascular geometry and blood flow within the artery. In recent scenarios, because of higher thermal properties and the ability to move across stenosis and tumor cells, nanoparticles are becoming a more common and effective approach in treating cardiovascular diseases and cancer cells.

The present mathematical study investigates the blood flow behavior in the overlapped stenosed curved artery with cylinder shape catheter. The induced magnetic field and entropy generation for blood flow in the presence of a heat source, magnetic field and nanoparticle (Fe₃O₄) have been analyzed numerically. Blood is considered in artery as two-phases: core and plasma region. Power-law fluid has been considered for core region fluid, whereas Newtonian fluid is considered in the plasma region. Strongly implicit Stone’s method has been considered to solve the system of nonlinear partial differential equations (PDE’s) with 10–6 tolerance error.

The influence of various parameters has been discussed graphically. This study concludes that arterial curvature increases the probability of atherosclerosis deposition, while using an external heating source flow temperature and entropy production. In addition, if the thermal treatment procedure is carried out inside a magnetic field, it will aid in controlling blood flow velocity.

The findings of this computational analysis hold great significance for clinical researchers and biologists, as they offer the ability to anticipate the occurrence of endothelial cell injury and plaque accumulation in curved arteries with specific wall shear stress patterns. Consequently, these insights may contribute to the potential alleviation of the severity of these illnesses. Furthermore, the application of nanoparticles and external heat sources in the discipline of blood circulation has potential in the medically healing of illness conditions such as stenosis, cancer cells and muscular discomfort through the usage of beneficial effects.

To present the detailed implementation processes of the IDEAL algorithm for two-dimensional compressible flows based on Delaunay triangular mesh, and compare the performance of the SIMPLE and IDEAL algorithms for solving compressible problems. What’s more, the implementation processes of Delaunay mesh generation and derivation of the pressure correction equation are also introduced.

Programming completely in C++.

Five compressible examples are used to test the SIMPLE and IDEAL algorithms, and the comparison with measurement data shows good agreement. The IDEAL algorithm has much better performance in both convergence rate and stability over the SIMPLE algorithm.

The detail solution procedure of implementing the IDEAL algorithm for compressible flows based on Delaunay triangular mesh is presented in this work, seemingly first in the literature.

Tourism and health outbreaks share a symbiotic history (Hall, Scott, & Gössling, 2020; Ozbay, Sariisik, Ceylan, & Çakmak, 2021). Pandemics, epidemics, and endemics have transformed the perception of tourists. Previous outbreaks were geographically limited, resulting in the substitution effect (Prideaux, 2005; van der Veen, 2014). However, the COVID-19 pandemic urged the authorities to cease mobility worldwide. Evidently, mobility-oriented businesses like tourism have received immediate impacts from the pandemic. From shutdown to the minimum clearances, under strict restrictions, the tourism industry suffered atypical outcomes. Heat check-meters, contactless check-ins and check-outs, automotive service trays and counters, and reduced carrying capacity have been introduced to curb the impact of the pandemic on tourism. Tourism requires, throughout its cycle—before, during, and after the trip—the use of artificial intelligence, virtual reality, augmented reality, the internet of things, and geotargeting (Buhalis & Amaranggana, 2015). The usage of technology has been assured to be compatible with the prerequisites of restrictive and compliance measures (Lau, 2020). Moreover, in the supply sector, a competitive environment has also been created to market these new modified products and services. This chapter pursues the investigation of new offerings in a different normal, concerned with health issues, ethical behaviors, and trips with a social purpose to contribute to local development. Secondary data analysis has been performed to achieve this goal. This study implicates the new offerings duly implemented during the new normal.

The purpose of this study is to investigate how participating in a multicultural education course impacted bilingual preservice teachers' (BPSTs) conceptions of identity and how they were able to use their experiential knowledge to create a virtual library based on a variety of topics related to multicultural education.

This qualitative case study examines the experiences of three BPST candidates within a multicultural education course during the fall 2020 semester. The authors focused on three preservice teachers’ written reflections, interviews and work samples based on a virtual library project.

The authors describe the critical role BPST preparation programs have in developing coursework that provides opportunities for building a positive self-identity that values life experiences. Such opportunities foster BPSTs’ ability to create lessons that are reflective of identity and diversity inclusive of culture, language, immigration and LGBTQ+.

For some time now, researchers have examined how teacher education programs should include opportunities to interrogate preservice teachers' own experiences in K-12. However, few researchers have directly documented how to connect these experiences to preservice teacher coursework and create classroom resources based on these critical reflections.

This study aims to identify sustainability indicators in the energy sector through a literature review and validate them from the perspective and context of professionals working in the sector in an emerging economy country, Brazil, considering the relationship of these indicators with the achievement of the targets set by the United Nations sustainable development goals (UN SDGs).

To accomplish this, a literature review on sustainability indicators specific to the energy sector was conducted. Subsequently, a research instrument (questionnaire) based on the identified indicators was developed and a survey was administered to professionals in the field. The collected data were analyzed using the Lawshe method.

The results revealed 20 indicators, distributed across environmental, economic and social dimensions. Among these, nine indicators were validated, including global impacts, local impacts, renewable energy production as a percentage of total production, greenhouse gas emissions, access to electricity, investment in the energy sector, installed capacity in the electricity sector, energy prices in the end-use sector and energy distribution and conversion efficiency.

Consequently, it was possible to determine which SDGs are directly impacted and provide a foundation for future actions that can contribute to the sustainable advancement of the energy sector in emerging countries.

Aero-engine exhaust plume length can be more than the aircraft length, making it easier to detect and track by infrared seeker. Aim of this study is to analyze the effect of free stream Mach number (M_∞) on length of potential core of plume. Also, change in infrared (IR) signature of plume and aircraft surface with variation in elevation angle (θ) is examined.

Convergent divergent (CD) nozzle is located outside the rear fuselage of the aircraft. A two dimensional axisymmetric computational fluid dynamics (CFD) study was carried out to study effect of M_∞ on potential core. The CFD data with aircraft and plume was then used for IR signature analysis. The sensor position is changed with respect to aircraft from directly bottom towards frontal section of aircraft. The IR signature is studied in mid wave IR (MWIR) and long wave IR (LWIR) band.

The potential plume core length and width increases as M_∞ increases. At higher altitudes, the potential core length increases for a fixed M_∞. The plume emits radiation in the MWIR band, whereas the aerodynamically heated aircraft surface emits IR in the LWIR band. The IR signature in the MWIR band continuously decreases as the sensor position changes from directly bottom towards frontal. In the LWIR band the IR signature initially decreases as the sensor moves from the directly bottom to the frontal, as the sensor begins to see the wing leading edges and nose cone, the IR signature in the LWIR band slightly increases.

The novelty of this study comes from the data reported on the effect of free stream Mach number on the potential plume core and variation of the overall IR signature of aircraft with change in elevation angle from directly below towards frontal section of aircraft.

The purpose of this study is an assessment of the existing roughness models to simulate the flow in the narrow gap between corotating and rough disks. A specific configuration of the flow through the gap, which forms a minichannel with variable cross sections and rotating walls, makes it a complex problem and, therefore, worth discussing in more detail.

Two roughness models were examined, the first one was based on the wall function modification by application of the shift in the dimensionless velocity profile, and the second one was based on the correction of turbulence parameters at the wall, proposed by Aupoix. Due to the lack of data to validate that specific case, the approach to deal with was selected after a systematic study of reported test cases. It started with a zero-pressure-gradient boundary layer in the flow over a flat plate, continued with flow through minichannels with stationary walls, and finally, focused on the flow between corotating discs, pertaining each time to smooth and rough surfaces.

The limitations of the roughness models were highlighted, which make the models not reliable in the application to minichannel flows. It concerns turbulence models, near-wall discretization and roughness approaches. Aupoix’s method to account for roughness was selected, and the influence of minichannel height, mass flow rate, fluid properties and roughness height on the velocity profile between corotating discs in both smooth and rough cases was discussed.

The originality of this study is the evaluation and validation of different methods to account for the roughness in rotating mini channels, where the protrusions can cover a substantial part of the channel. Flow behavior and performance of different turbulence models were analyzed as well.

This research aims to explore the role of awareness of harm and responsibility for environmental protection in reducing pollution from single-use plastic bags (SPBs) in coastal communities (CCs). To this end, this study develops and tests a unique model that explains residents’ intention to reduce the use of SPBs in coastal regions.

A questionnaire was used to collect data from 721 coastal residents in Vietnam. Structural equation modeling and moderation analysis were applied to test the proposed hypotheses.

The results show that awareness of the impact of SPBs on the environment and human health and awareness of the responsibility to protect the coastal environment significantly affect attitudes and intentions to reduce the use of SPBs. Moreover, such awareness of responsibility strengthens the attitude-intention relationship.

The findings suggest that CCs should not receive a lower priority in campaigns and efforts to reduce SPBs. In this regard, providing residents with free environmentally friendly bags and education programs on the impact of SPBs could be implemented.

CCs are directly impacted by pollution from SPBs. However, little is known about how this affects their polluting behavior. This study shows that CCs are not immune to polluting behaviors and that SPBs can be significant among residents. It also demonstrates that awareness of harm and feeling responsible for the environment are essential drivers of (intended) sustainable behaviors.

Performance appraisal (PA) is an organizational practice whose ultimate goal is to improve employee performance. This goal can be achieved using two approaches: the administrative approach, which emphasizes materialistic incentives and rewards excellent performers, and the developmental approach, which focuses on employee personal and professional development. The literature points out that organizations cannot utilize both approaches at the same time, but the reason for this is vague. Therefore, the research purpose is to bridge this gap by exploring the basic assumptions behind the administrative and developmental PA approaches as part of the hidden layers of organizational culture.

A qualitative document analysis (QDA) was used to analyze 124 Israeli organizations' PA forms and employee reports.

The organization's PA approaches were diagnosed as a first step in revealing the reason for the inability to use both approaches simultaneously. In the next step, it was revealed that organizational culture assumptions are the reason for the contradiction of the PA approaches. Eventually, McGregor's theory X is the basic assumption behind the administrative approach, and theory Y is the assumption behind the developmental approach. Since these two approaches contradict each other, it explains the difficulty of using both approaches simultaneously.

This study dives into the hidden levels of organizational culture and attempts to bridge a long-standing but still current research gap, as well as extend and refine organizational culture and performance appraisal theories.