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The lattice Boltzmann method is used to simulate the nanofluid flow and heat transfer inside a finned multi-pipe heat exchanger.

The heat exchanger is filled with CuO-water nanofluid. The Koo–Kleinstreuer–Li (KKL) model is used to estimate the dynamic viscosity and considering the Brownian motion in the simulation. On the other hand, the influence of nanoparticles’ shapes on the heat transfer rate is considered, and the best efficient shape is selected to be used in the investigation.

The Rayleigh number, nanoparticle concentration and the thermal arrangements of internal active fins and bodies are the governing parameters. In addition, the impacts of these two parameters on the nanofluid flow, heat transfer rate, local and total entropy generation and heatline visualization are analyzed, comprehensively.

The originality of this work is using of lattice Boltzmann method for simulation of nanofluid flow and heat transfer during natural convection in a heat exchanger. Furthermore, influence of the shape of nanoparticles on the thermo-physical properties of nanofluid is analyzed using Koo–Kleinstreuer–Li correlation.

In parallel sampling method, the size of the sampling capacitor is reduced to improve the bandwidth of the ADC.

Various low-power techniques for 10-bit 200MS/s pipelined analog-to-digital converter (ADC) are presented. This work comprises two techniques including parallel sampling and switched op-amp sharing technique.

This paper aims to study the effect of parallel sampling and switched op-amp sharing techniques on power consumption in pipelined ADC. In switched op-amp sharing technique, the numbers of op-amps used in the stages are reduced. Because of the reduction in the size of capacitors in parallel sampling technique and op-amps in the switched op-amp sharing technique, the power consumption of the proposed pipelined ADC is reduced to a greater extent.

Simulated the 10-bit 200MS/s pipelined ADC with complementary metal oxide semiconductor process and the simulation results shows a maximum differential non-linearity of +0.31/−0.31 LSB and the maximum integral non-linearity (of +0.74/−0.74 LSB with 62.9 dB SFDR, 55.90 dB SNDR and ENOB of 8.99 bits, respectively, for 18mW power consumption with the supply voltage of 1.8 V.

This research aims to provide a comparative study of the effect of conventional zinc phosphate (ZP) and zinc aluminium phosphate (ZPA) representing second generation of phosphate-based anticorrosion pigments on the protective performance and physical mechanical properties of a solvent-borne polyurethane (PU) coating.

The two pigments were incorporated into the coating at optimum pigment volume concentration. To evaluate the protective performance, electrochemical impedance spectroscopy (EIS) was used. The effect of modification of ZP on the physical–mechanical properties of the coatings was studied through dynamic mechanical thermal analysis. Moreover, Micro Vickers hardness and pull-off tests were used to evaluate the hydrolytic coating degradation.

EIS revealed the superior protective function of coatings incorporated with ZPA compared to those formulated with ZP. This behaviour might be attributed to the release of sufficient inhibiting species because of partial dissolving of the anticorrosive pigments when an electrolyte penetrates into the coating. In addition, the effectiveness of modification of ZP on the physical–mechanical properties of coatings was shown.

As a classical replacement for the toxic chromates, ZP has been widely used in the formulation of protective coatings. However, undesirable inhibitive function of the pigment arising from its low solubility has made modification necessary. Because of the modified solubility, second generation of phosphate-based anticorrosion pigments has been reported to reveal superior performance.

According to the literature, no report can be found studying the effect of the second generation of phosphate-based anticorrosion pigments on the physical–mechanical properties of PU coatings. The main goal of this work is to study the correlation between physical–mechanical properties and anticorrosion performance of the PU coatings.

The exploration of performance determinants in social enterprises has gained increasing relevance among researchers and practitioners, particularly in rural tourism. The purpose of this paper is to analyze the contributions of transformational leadership and social entrepreneurship to the performance of social enterprises in the context of rural tourism. Further, the mediating roles of social capital, creativity and social value were investigated.

Data were gathered through a survey of 168 employees of social enterprises operating in the rural tourism setting. Eight surveyors were sent out to conduct the survey. Data were analyzed by structural equation modeling (SEM) using AMOS 18.0.

The results of the SEM suggested that transformational leadership is positively associated with social value, social capital and performance of social enterprise. In addition, social entrepreneurship had a significant influence on social value, social capital and performance of social enterprise. Creativity and social value predicts the performance of social enterprise. Further, social capital was found to have a positive relationship with creativity. Finally, the mediating roles of social capital, creativity and social value were also confirmed. The findings thus highlight the power of the social value creation and social capital in the social enterprises operating in the rural destinations.

The findings assert that social entrepreneurship and transformational leadership are key sources of social value creation, social capital and creativity in rural tourism context indicating the need for additional efforts on this kind of entrepreneurial activity. The findings can motivate policymakers to promote social entrepreneurship in rural tourism destinations as a means of stimulating bottom-up social capital and social value creation.

This study is among the first to examine the hypothesized relationships focusing on tourism social enterprises.

This paper aims to address a distributed assembly permutation flow-shop scheduling problem (DAPFSP) considering budget constraints and factory eligibility. The first stage of the considered production system is composed of several non-identical factories with different technology levels and so the factories' performance is different in terms of processing time and cost. The second stage is an assembly stage wherein there are some parallel work stations to assemble the ready parts into the products. The objective function is to minimize the maximum completion time of products (makespan).

First, the problem is formulated as mixed-integer linear programing (MIP) model. In view of the nondeterministic polynomial (NP)-hard nature, three approximate algorithms are adopted based on variable neighborhood search (VNS) and the Johnsons' rule to solve the problem on the practical scales. The proposed algorithms are applied to solve some test instances in different sizes.

Comparison result to mathematical model validates the performance accuracy and efficiency of three proposed methods. In addition, the result demonstrated that the proposed two-level self-adaptive variable neighborhood search (TLSAVNS) algorithm outperforms the other two proposed methods. Moreover, the proposed model highlighted the effects of budget constraints and factory eligibility on the makespan. Supplementary analysis was presented by adjusting different amounts of the budget for controlling the makespan and total expected costs. The proposed solution approach can provide proper alternatives for managers to make a trade-off in different various situations.

The problem of distributed assembly permutation flow-shop scheduling is traditionally studied considering identical factories. However, processing factories as an important element in the supply chain use different technology levels in the real world. The current paper is the first study that investigates that problem under non-identical factories condition. In addition, the impact of different technology levels is investigated in terms of operational costs, quality levels and processing times.

In this investigation, attempts were made to distinguish critical coating faults in order of repair priority in DCVG+CIPS survey data by new proposed equation for calculating IR drop. The paper aims to discuss these issues.

DCVG+CIPS, XRD, EDS.

A new empirical equation was developed which is able to predict the importance more precisely. Besides, the studies proved the corrosion products were mainly hematite and goethite, and the presence of Cl anions was not noticed. As a result, the corrosion attack had a form of non-uniform localized corrosion.

The values were gathered by DCVG+CIPS method of survey.

This paper aims to examine how technological media accelerates sustainable development. Further, the mediating role of good governance and society empowerment would be investigated.

A questionnaire survey was conducted among 450 students at the level of higher education using stratified sampling plan. Following a two-step approach, a measurement model was estimated and then a structural model was analyzed to evaluate five proposed hypotheses.

The research results indicate that technological media has a direct and positive effect on good governance, empowerment and sustainable development; technological media has an indirect and positive influence on sustainable development via good governance and empowerment as mediating variables; good governance and empowerment are significant antecedents of sustainable development.

The research examines the relationship among technological media, good governance, empowerment and sustainable development, thus contributing to sustainable development literature theoretically. In addition, relevant implications are provided for policymakers as to how to accelerate development sustainably across their countries.

One major challenge in turbulent flow applications is to control the recirculation zone behind the backward‐facing step (BFS). One simple idea to do so is to modify the original BFS geometry, of course, without causing adverse or undesirable impacts on the original characteristics of the primary stream. The main objective of this work is to examine the solidity of the recirculation zone behind several different geometries which are slightly to moderately different from the original BFS geometry.

The implemented modifications cause complicated irregularities at the boundaries of the domain. The experience shows that the mesh distribution around these irregularities plays a critical role in the accuracy of the numerical solutions. To achieve the most accurate solutions with the least computational efforts, we use a robust hybrid strategy to distribute the computational grids in the domain. Additionally, a suitable numerical algorithm capable of handling hybrid grid topologies is properly extended to analyze the flow field. The current fully implicit method utilizes a physical pressure‐based upwinding scheme capable of working on hybrid mesh.

The extended algorithm is very robust and obtains very accurate solutions for the complex flow fields despite utilizing very coarse grid resolutions. Additionally, different proposed geometries revealed very similar separated regions behind the step and performed minor differences in the location of the reattachment points.

The current study is fulfilled two‐dimensionally. However, the measurements in testing regular BFS problems have shown that the separated shear layer behind the step is not affected by 3D influences provided that the width of channel is sufficiently wide. A similar conclusion is anticipated here.

The problem occurs in the pipe and channel expansions, combustion chambers, flow over flying objects with abrupt contraction on their external surfaces, etc.

A novel pressure‐based upwinding strategy is properly employed to solve flow on multiblocked hybrid grid topologies. This strategy takes into account the physics associated with all the transports in the flow field. To study the impact of shape improvement, several modified BFS configurations were suggested and examined. These configurations need only little additional manufacturing cost to be fabricated.

The purpose of this study is to investigate the role of millennial tourists’ accommodation service experiences (ASEs) on their satisfaction, word-of-mouth (WOM) and revisit intentions (RIs) in an emerging economy.

A survey instrument was used to collect cross-sectional data from millennial tourists, and the 282 valid datasets were analyzed using structural equation modeling.

The results demonstrated that ASE had a beneficial impact on satisfaction and WOM but not on RI. Significant positive associations between tourist satisfaction, WOM and RI were also discovered. Additionally, WOM research sheds new light on how the ASE of millennial tourists affects their satisfaction, WOM and propensity to return. Furthermore, results show that WOM intentions and satisfaction mediate the relationship between ASE and RIs.

The study presents a unique research context, the application of advanced statistical techniques and the comprehensive investigation of key outcome variables in the context of millennial tourists’ ASEs in an emerging economy. This study contributes significantly to the body of knowledge in the field of tourism research, aiming to meet long-term goals in a sustainable way for the hospitality industry operators by integrating ASE, satisfaction, WOM and RI. Additionally, the study presents the mediating role of WOM and satisfaction in the millennial tourists’ emerging country context.

This viewpoint paper aims to discuss the notion of frugality in the Malaysian hotel industry. It is also critically argued how frugality could address the future and generate appropriate measures for sustainable development goals in the tourism industry. 

Based on a review of the relevant literature and drawing upon the current practices of the hotel industry in Malaysia, this viewpoint paper highlights the debate on the potential of frugality, its implications, challenges and the future that it will bring.

This viewpoint paper briefly outlines the overconsumption issues of the Malaysian hotel industry, which represents the scenario of many other global tourism industries. It also emphasises adopting frugal approaches/behaviour to manage the overconsumption issues in this industry. Additionally, it presents a futuristic approach to achieving sustainable tourism for the Malaysian hotel industry, which other tourism players in various parts of the world can adopt. Finally, the challenges, implications, recommendations and future direction are also addressed. 

It is expected that the issues highlighted in this viewpoint will be helpful for the academicians, hoteliers and other relevant stakeholders to better understand the notion of frugality towards achieving sustainable tourism.

This viewpoint paper is among the pioneers to critically discuss the prospect of frugality as a solution to the overconsumption issue in the hotel industry.