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This study aims to perform the surface treatment of synthetic α-Fe₂O₃ red iron oxide pigment with hydrolysate 3-aminopropyl silane (A) and colloidal silica (CS) and investigate the effects of surface-treated pigment on the styrene acrylic (SA) emulsion and polyurethane (PU) dispersion.

For this purpose, firstly red iron oxide particles were modified with A and CS separately in an aqueous medium. After isolation of the modified iron oxide were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). Moreover, the degree of the dispersion stability of the modified pigment in coatings with SA emulsion and PU dispersion was investigated by using an oscillation rheometer. Loss (G''), storage (G') modulus, loss factor [tan(δ)] and yield stress (τ⁰) values were determined by performing amplitude and frequency sweep tests.

The τ⁰ in SA coatings decreases with the amount of used A and increases with the amount of used CS. The τ⁰ decreases as the amount of used A and CS in PU coatings increases. The use of CS on red iron oxide pigments causes storage modulus to increase in SA coatings at low angular frequencies, while it causes a decrease in PU coatings.

To the best of the authors’ knowledge, for the first time, the suspended state of the iron oxide hybrid pigment formed with CS in the coating was investigated rheologically in this study.

This study involves the development of a PSPICE 5.4 package oriented model for the dynamic behaviour of a series excited synchronised slip ring induction motor including the bridge rectifier for rotor circuit excitation. Furthermore, in this study is aimed at investigating the synchronising behaviour for various rotor connections of a series excited synchronous motor formed by connecting a bridge rectifier input in series with the stator winding of a slip‐ring induction motor whereas the rectifier output feeds the rotor winding. The steady state behaviour of such a scheme in comparison to a separately excited one is well known, but the behaviour during synchronisation requires further study. Presentation of results obtained by a PSPICE based simulation and comparison with experimental results acquired during this study points to a model to account for design variations and additional circuitry. It is convenient to use this model in a drive system. The advantage of this simulation method over the others is that it does not involve the utilisation of specialised programs and mathematical difficulties such as the solution of stiff differential equations. Furthermore, steady state behaviour of the scheme is explained by means of a simple analysis and illustrated by test results.

In this study, a single‐phase induction motor with constant v/f, fed by matrix converter, is considered under various frequencies. The modeling of the motor, mechanical load for single phase induction motor and matrix converter have been obtained by using Simulink package program. The performance of the motor under various frequencies is determined. A single‐phase induction motor considered in this work has a running capacitor. The analysis and simulation results are presented.

This paper aims to understand the emergence, the revolution and the relevant knowledge of academic research concentrating on social media (SM) and hospitality and tourism firms’ financial performance. The authors not only identified the gaps and critical issues in research but also re-conceptualized profound directions for the future research in technology and finance in the hospitality and tourism field.

This study adopted an in-depth review analysis to investigate and review previous scholarly papers published in hospitality, tourism and hospitality and tourism journals from January 2011 to the present. The authors thoroughly analyzed and reviewed peer-reviewed/refereed, blind-reviewed, full-length published articles and working papers within SM and hospitality firms’ financial performance. Editor notes, prefaces, research notes, industry articles, internet publications, conference preceding, books and book chapters were excluded.

Having examined the empirical content of 26 peer-reviewed scholarly articles, the authors clearly observed that none of the papers went beyond analyzing the effect of SM on hotels’ revenue per available room, revenues, net profit, average daily rate, occupancy rates, net operating income, etc., and all papers ignored the analysis of many critical financial proxies.

This critique and review paper is limited to the relationship between SM and firms’ financial performance within the hospitality and tourism context.

This review provides a blueprint to guide future research, facilitate knowledge accumulation and create a new understanding and awareness in practice as well as SM and financial performance research.

This paper complements and adds to previous work by demonstrating various aspects, evidences, findings and inferences regarding the association between online SM platforms and firms’ financial performance and by proposing rigorous abstract and specific future extensions to both practice and discipline-specific knowledge.

There is an absence of the most updated review study of published papers on SM and hospitality and tourism firms’ financial performance. Although how SM contributes to firms’ financial performance is clear to academicians and industry professionals, no solid consensus or theoretical certainty about what the authors know and do not know has been achieved.

The purpose of this paper is to introduce and explore blockchain technology and its potential implementation to hospitality and tourism firms’ wide range of business operations and transactions from a technological and functional point of view. This study’s central interest is to produce novel and rigorous in-depth-review analysis and foundations for a broad discussion and outlook on the potential applications of blockchain technology benefiting hospitality and tourism research, as well as the industry as a whole.

This study identifies and proposes several potential areas of the adoption and implementation of blockchain technology to the hospitality and tourism industry, including payment and cryptocurrencies, tracking and service customization, the disintermediation of hospitality and tourism, innovative loyalty programs, smart contracts, integrated property management systems, verified rating and review systems, collaborative initiatives and due diligence and smart tourism, each of which represents fertile avenues for future research.

This paper provides extensive critical discussions, reviews and answers to a fundamental question: “What critical functions of Blockchain mechanisms can be implemented to the existing core operational (i.e. booking and reservation systems, guest management, etc.) and business functions (i.e. loyalty/reward programs, agent transactions, etc.) of hospitality and tourism companies?”.

Future studies should specifically delve further into various angles of this “BizTech” environment based not only on business operations and competition but also on vendor and customer collaboration.

This study intends to serve as a guidance for future research, facilitate knowledge accumulation and create a new understanding and awareness in both practice and academia. One of the most important applications of blockchain in this industry would be that pertaining to direct booking, online reservation systems (i.e. airlines and online travel agencies) and check-in/out with digital identities. With industry-wide blockchain adoption, guests’ personal information can be digitally validated, saved and secured as previously established cryptographically secured codes verify one’s identity without disclosing essential personal information.

It is obvious that the hospitality and tourism industry needs urgent technological transformation, industrial innovations and new growth avenues such as the adoption of blockchain technology and systems to maintain its global market share in the future. Therefore, the implementation of blockchain systems can promote the formation of multi-center (i.e. guest operations and customer service), weakly intermediated (i.e. loyalty programs and/or review and rating systems) areas in this industry.

This paper aims to determine the knowledge and attitudes of the physicians regarding human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS), to emphasize that these patients exist and they will exist in the future and to raise awareness so as to prevent that their rights to treatment are revoked.

The survey was conducted via a link sent through an online system. Random physicians from 81 cities of the country were invited to the survey. The survey has 41 questions regarding knowledge and attitudes in total, including epidemiological information such as age, gender and title.

A total of 3,107 physicians has voluntarily participated in the study. In total, 2,195 (70.7%) are internal physicians and 912 (29.3%) are surgical physicians among the participant physicians. In total, 1,452 (46.7%) of the participants are specialist physicians, 608 (19.6%) of the participants are practising physician and the rest of it is physician assistants, academicians and dentists, respectively.

In this study, it has been found out that the physicians have a lack of knowledge on HIV/AIDS and they adopt a discriminatory attitude towards HIV-positive persons. HIV-positive patients who are exposed to discrimination and scared of being uncovered refrain from applying to hospitals for treatment, which puts public health into jeopardy due to the high viral load and these patients are faced with difficulties in coping with both medical and emotional load of the disease.

Research has provided powerful evidence that what teachers do in the classroom matters most for the learning of students. Evidence also suggests that school leaders can make a significant difference to student learning via their influence on teachers' attitudes, beliefs and classroom practices. The purpose of this study was to examine if/how principal instructional leadership practices affect differentiated instruction in Omani schools, and understand the role that teacher collaboration and self-efficacy play in this dynamic.

The study used structural equation modeling (SEM) to analyze data collected from a sample of 496 teachers working in public schools in Muscat, Oman.

The findings revealed no direct association between principal instructional leadership and differentiated instruction. Instead, the effects of principal instructional leadership on differentiated instruction were achieved indirectly through the mediation of teacher collaboration and teacher self-efficacy. Collaboration was also found to have a positive influence on the teachers' self-efficacy beliefs.

The significance of this study stems from its relevance to the educational developments unfolding not only in Oman, but in the Gulf region at large. Recent reviews of educational administration and leadership research in the Gulf states indicate the scarcity of empirical research investigating the relationship between principal leadership and teacher practices. This is problematic as it creates a gap in our knowledge of the factors that can support ongoing school improvement initiatives in the region. More specifically, we expect our findings to guide current educational reforms aimed at raising education quality via promoting effective teaching and learning in Omani schools.

The purpose of this paper is to present a comparison of nonlinear and linear simulations of aircraft dynamics to determine the divergence of the linear solution from the nonlinear solution.

The general equations of motion of a transport aircraft are presented both in nonlinear and linear form. The nonlinear equations are solved by using the Runge Kutta method. Linear equations are solved numerically by using the Runge Kutta method and they are also solved exactly by using the Laplace transformation method. All of these solutions are obtained by using the body axis system. The results of the simulations are plotted for different control deflections.

Solution of linear equations by both methods gave the same results as expected. There are important differences in amplitude and frequency of oscillations which are obtained by using nonlinear and linear equations. These differences increase with growing input control deflection. Therefore, it is appropriate to prefer nonlinear approach to obtain more satisfactory results.

Accurate determination of the aerodynamic derivatives is important for the accuracy of the nonlinear solutions.

Many classical approaches use stability axis system for the solution of linear equations. However, in this paper transfer functions of the aircraft are redefined in the body axis system, because stability axes change with angle of attack and some of the stability derivatives need to be re‐evaluated for each angle of attack. Moreover, in addition to classical text book, linear equations are also solved by using the 4th order Runge Kutta medhod.

Examines the fourteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.