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Article
Publication date: 17 May 2013

Abdullah M. Asiri, Khalid A. Alamry and Mahmoud A. Hussein

The purpose of this paper is to investigate the effect of annealing on photochromic performance of (E)‐dicyclopropylmethylene‐(2, 5‐dimethyl‐3‐furylethylid‐ene)‐succinicanhydride…

143

Abstract

Purpose

The purpose of this paper is to investigate the effect of annealing on photochromic performance of (E)‐dicyclopropylmethylene‐(2, 5‐dimethyl‐3‐furylethylid‐ene)‐succinicanhydride doped in polyacrylic acid thin film.

Design/methodology/approach

(E)‐dicyclopropylmethylene‐(2,5‐dimethyl‐3‐furyl‐ethylidene)‐succinic‐anhydride (DMDFS‐E) fulgide doped in polyacrylic acid thin films was prepared. DMDFS‐E fulgide doped in polyacrylic acid thin films was heated at various annealing temperatures. Photocoloration, photobleaching and photochemical fatigue resistance for the desired DMDFS‐E fulgide doped in polyacrylic acid thin films were studied.

Findings

Upon irradiation with UV light (366 nm), fulgide DMDFS‐E undergoes a conrotatory ring closure to the pinkish colored closed form C (523 nm). The later color was switched back to the original color when the films were irradiated with white light. The kinetics of photocoloration and photobleaching processes were followed spectrophotometrically by monitoring the absorbance of the ring closed product DMDFS‐C at its λmax of 523 nm. The first‐order plots of photocoloration reaction showed distinct linear line at different temperatures. The slope of these first‐order lines corresponding to the rate constants k. It was found that for photocoloration reaction, the rate constant of the photocoloration reaction was slower than the photobleaching reaction and both reactions decrease with increasing the annealing temperatures. It was found that there was almost improvement of photochemical fatigue resistance of fulgide DMDFS‐E doped in polyacrylic acid thin film at several of the annealing temperatures.

Originality/value

The results obtained in this work showed that the photochromic properties of DMDFS fulgide E were improved upon annealing the film at 100°C. Therefore, it would be recommended for improvement to apply fulgides as annealed polymer films.

Details

Pigment & Resin Technology, vol. 42 no. 3
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 18 July 2019

Zahid Ahmed, Sohail Nadeem, Salman Saleem and Rahmat Ellahi

The purpose of this paper is to present a novel model on the unsteady MHD flow of heat transfer in carbon nanotubes with variable viscosity over a shrinking surface.

307

Abstract

Purpose

The purpose of this paper is to present a novel model on the unsteady MHD flow of heat transfer in carbon nanotubes with variable viscosity over a shrinking surface.

Design/methodology/approach

The temperature-dependent viscosity makes the proposed model non-linear and coupled. Consequently, the resulting non-linear partial differential equations are first reformed into set of ordinary differential equations through appropriate transformations and boundary layer approximation and are then solved numerically by the Keller box method.

Findings

Graphical and numerical results are executed keeping temperature-dependent viscosity of nanofluid. It is noted that, for diverse critical points, it is found that at one side of these critical values, multiple solutions exist; on the other side, no solution exists. A comparison is also computed for the special case of existing study. The temperature and pressure profiles are also plotted for various effective parameters.

Originality/value

The work is original.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 12
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 27 June 2023

Syihabuddin Syihabuddin, Nurul Murtadho, Yusring Sanusi Baso, Hikmah Maulani and Shofa Musthofa Khalid

Assessing whether a book is relevant or suitable for use in teaching materials is not an easy and haphazard matter, various methods and theories have been offered by researchers…

167

Abstract

Purpose

Assessing whether a book is relevant or suitable for use in teaching materials is not an easy and haphazard matter, various methods and theories have been offered by researchers in studying this matter. Taking a study of the context of textbooks, researchers found the urgency that textbooks are a foundation for education, socialization and transmission of knowledge and its construction. Researchers offer another approach, namely by using praxeology as a study tool so that the goals of the textbooks previously intended are fulfilled.

Design/methodology/approach

The researcher uses a qualitative approach through grounded theory. Grounded theory procedures are designed to develop a well-integrated set of concepts that provide a thorough theoretical explanation of the social phenomena under study. A grounded theory must explain as well as describe. It may also implicitly provide some degree of predictability, but only with respect to certain conditions (Corbin and Strauss, 1990). Document analysis in conducting this research study. Document analysis itself examines systematic procedures for reviewing or evaluating documents, both printed and electronic materials.

Findings

Two issues regarding gender acquisition have been investigated in L2 Arabic acquisition studies; the order in which L2 Arabic learners acquire certain grammatical features of the gender system and the effect of L1 on the acquisition of some grammatical features from L2 grammatical gender. Arabic has a two-gender system that classifies all nouns, animate and inanimate, as masculine or feminine. Verbs, nouns, adjectives, personal, demonstrative and relative pronouns related to nouns in the syntactic structure of sentences show gender agreement.

Research limitations/implications

In practice, as a book intended for non-speakers, the book is presented using a general view of linguistic theory. In relation to the gender agreement, the presentation of the book begins and is inserted with the concepts of nouns and verbs. Returning to the praxeology context, First, The Know How (Praxis) explains practice (i.e. the tasks performed and the techniques used). Second, To Know Why or Knowledge (logos) which explains and justifies practice from a technological and theoretical point of view. Answering the first concept, the exercise presented in the book is a concept with three clusters explained at the beginning of the discussion. And the second concept, explained with a task design approach which includes word categorization by separating masculine and feminine word forms.

Practical implications

Practically, this research obtains perspectives studied from a textbook, namely the Arabic gender agreement is presented with various examples of noun contexts; textbook authors present book concepts in a particular way with regard to curriculum features and this task design affects student performance, and which approach is more effective for developing student understanding. Empirically, the material is in line with the formulation of competency standards for non-Arabic speakers in Indonesia.

Originality/value

With this computational search, the researcher found a novelty that was considered accurate by taking the praxeology context as a review in the analysis of non-speaking Arabic textbooks, especially in the year 2022 (last data collection in September) there has been no study on this context. So then, the researcher finds other interests in that praxeology can examine more broadly parts of the task of the contents of the book with the approach of relevant linguistic theories.

Details

Journal of Applied Research in Higher Education, vol. 16 no. 4
Type: Research Article
ISSN: 2050-7003

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Article
Publication date: 30 April 2021

Amneh Hamida, Abdulsalam Alsudairi, Khalid Alshaibani and Othman Alshamrani

Buildings are responsible for the consumption of around 40% of energy in the world and account for one-third of greenhouses gas emissions. In Saudi Arabia, residential buildings…

923

Abstract

Purpose

Buildings are responsible for the consumption of around 40% of energy in the world and account for one-third of greenhouses gas emissions. In Saudi Arabia, residential buildings consume half of total energy among other building sectors. This study aims to explore the impact of sixteen envelope variables on the operational and embodied carbon of a typical Saudi house with over 20 years of operation.

Design/methodology/approach

A simulation approach has been adopted to examine the effects of envelope variables including external wall type, roof type, glazing type, window to wall ratio (WWR) and shading device. To model the building and define the envelope materials and quantify the annual energy consumption, DesignBuilder software was used. Following modelling, operational carbon was calculated. A “cradle-to-gate” approach was adopted to assess embodied carbon during the production of materials for the envelope variables based on the Inventory of Carbon Energy database.

Findings

The results showed that operational carbon represented 90% of total life cycle carbon, whilst embodied carbon accounted for 10%. The sensitivity analysis revealed that 25% WWR contributes to a significant increase in operational carbon by 47.4%. Additionally, the efficient block wall with marble has a major embodiment of carbon greater than the base case by 10.7%.

Research limitations/implications

This study is a contribution to the field of calculating the embodied and operational carbon emissions of a residential unit. Besides, it provides an examination of the impact of each envelope variable on both embodied and operational carbon. This study is limited by the impact of sixteen envelope variables on the embodied as well as operational carbon.

Originality/value

This study is the first attempt on investigating the effects of envelop variables on carbon footprint for residential buildings in Saudi Arabia.

Details

International Journal of Building Pathology and Adaptation, vol. 40 no. 5
Type: Research Article
ISSN: 2398-4708

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Article
Publication date: 7 April 2015

Ahmed Al Kuwaiti and Arun Vijay Subbarayalu

– The purpose of this paper was to examine the perceptions of students of health sciences on research training programs offered at Saudi universities.

453

Abstract

Purpose

The purpose of this paper was to examine the perceptions of students of health sciences on research training programs offered at Saudi universities.

Design/methodology/approach

A cross-sectional survey design was adopted to capture the perceptions of health science students about research training programs offered at selected Saudi universities. A criterion-based sampling technique was adopted, and accordingly, 630 students were selected to participate in the study. A pre-tested questionnaire tool titled, “Students Attitude towards Research (SAR) questionnaire ”, was used to capture student responses on a five-point Likert scale with respect to three dimensions, namely, extent of research activities offered in their college, involvement of faculty in research and the infrastructural facilities offered by the college for research. The students’ attitudes with respect to various components of research training programs were analyzed using mean and cumulative percentage of students satisfied with the training. Multivariate analysis of variance (MANOVA) was used to study whether there is any significant difference in attitudes among the students belonging to four health science programs of the seven selected universities.

Findings

The results of this study demonstrate that only less than 50 per cent of the students from the selected health science colleges are satisfied with the existing research training programs. There are significant differences in the students’ attitude toward research training programs offered in seven selected Saudi universities.

Originality/value

This is the first Saudi Arabia-based study that provides an alarming signal to educational-policy planners on students’ perceptions and attitudes toward research training programs offered in Saudi higher education institutions.

Details

Quality Assurance in Education, vol. 23 no. 2
Type: Research Article
ISSN: 0968-4883

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Article
Publication date: 17 June 2019

Arif Hussain, Muhammad Yousaf Malik, Mair Khan and Taimoor Salahuddin

The purpose of current flow configuration is to spotlights the thermophysical aspects of magnetohydrodynamics (MHD) viscoinelastic fluid flow over a stretching surface.

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Abstract

Purpose

The purpose of current flow configuration is to spotlights the thermophysical aspects of magnetohydrodynamics (MHD) viscoinelastic fluid flow over a stretching surface.

Design/methodology/approach

The fluid momentum problem is mathematically formulated by using the Prandtl–Eyring constitutive law. Also, the non-Fourier heat flux model is considered to disclose the heat transfer characteristics. The governing problem contains the nonlinear partial differential equations with appropriate boundary conditions. To facilitate the computation process, the governing problem is transmuted into dimensionless form via appropriate group of scaling transforms. The numerical technique shooting method is used to solve dimensionless boundary value problem.

Findings

The expressions for dimensionless velocity and temperature are found and investigated under different parametric conditions. The important features of fluid flow near the wall, i.e. wall friction factor and wall heat flux, are deliberated by altering the pertinent parameters. The impacts of governing parameters are highlighted in graphical as well as tabular manner against focused physical quantities (velocity, temperature, wall friction factor and wall heat flux). A comparison is presented to justify the computed results, it can be noticed that present results have quite resemblance with previous literature which led to confidence on the present computations.

Originality/value

The computed results are quite useful for researchers working in theoretical physics. Additionally, computed results are very useful in industry and daily-use processes.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 6
Type: Research Article
ISSN: 0961-5539

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Book part
Publication date: 3 July 2018

Tariq Elyas and Abdullah Ahmed Al-Ghamdi

This chapter briefly explores selected English and general education policy documents, curricula, and textbooks within the context of Kingdom of Saudi Arabia (KSA) from a Critical…

Abstract

This chapter briefly explores selected English and general education policy documents, curricula, and textbooks within the context of Kingdom of Saudi Arabia (KSA) from a Critical Discourse Analysis perspective and examines how they have changed pre- and post-21st century. First, a policy document related to education in KSA in general (pre-21st century) is analyzed along with an English language teaching (ELT) policy document of the same period. Next, two general policy documents post-21st century are explored, followed by one related to ELT policy. Finally, one post-21st century document related to higher education is discussed. The “network of practices” within which these documents are situated are first detailed, as well as the structural order of the discourse, and some linguistic analysis of the choice of vocabulary and grammatical structures (Meyer, 2001). Issues which might be problematic to the learning and teaching identities of the students and teachers interpreting these documents are also highlighted. Finally, we consider whether the network of practices at this institution and KSA in general “needs” the problems identified in the analysis and critically reflect on the analysis.

Details

Cross-nationally Comparative, Evidence-based Educational Policymaking and Reform
Type: Book
ISBN: 978-1-78743-767-8

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Article
Publication date: 23 September 2020

H. Waqas, M. Imran, Taseer Muhammad, Sadiq M. Sait and R. Ellahi

The purpose of this study is to discuss the Darcy–Forchheimer nanoliquid bio-convection flow by stretching cylinder/plate with modified heat and mass fluxes, activation energy and…

179

Abstract

Purpose

The purpose of this study is to discuss the Darcy–Forchheimer nanoliquid bio-convection flow by stretching cylinder/plate with modified heat and mass fluxes, activation energy and gyrotactic motile microorganism features.

Design/methodology/approach

The proposed flow model is based on flow rate, temperature of nanomaterials, volume fraction of nanoparticles and gyrotactic motile microorganisms. Heat and mass transport of nanoliquid is captured by the usage of popular Buongiorno relation, which allows us to evaluate novel characteristics of thermophoresis diffusion and Brownian movement. Additionally, Wu’s slip (second-order slip) mechanisms with double stratification are incorporated. For numerical and graphical results, the built-in bvp4c technique in computational software MATLAB along with shooting technique is used.

Findings

The influence of key elements is illustrated pictorially. Velocity decays for higher magnitude of first- and second-order velocity slips and bioconvection Rayleigh number. The velocity of fluid has an inverse relation with mixed convection parameter and local inertia coefficient. Temperature field enhances with the increase in estimation of thermal stratification Biot number and radiation parameter. A similar situation for concentration field is observed for mixed convection parameter and concentration relaxation parameter. Microorganism concentration profile decreases for higher values of bioconvection Lewis number and Peclet number. A detail discussion is given to see how the graphical aspects justify the physical ones.

Originality/value

To the best of the authors’ knowledge, original research work is not yet available in existing literature.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 31 no. 5
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 5 December 2024

Reem Abdullah Alamri

This study aims to investigate the pivotal role of leadership in fostering a health and safety (H&S) culture in Gulf Cooperation Council (GCC) countries and identify key…

10

Abstract

Purpose

This study aims to investigate the pivotal role of leadership in fostering a health and safety (H&S) culture in Gulf Cooperation Council (GCC) countries and identify key challenges faced by these nations. The promotion of H&S culture has become increasingly crucial, with GCC leaders playing a vital role in reducing employee turnover rates by ensuring a safe and healthy work environment. Despite substantial research into issues such as the lack of training, workforce diversity and employee engagement in promoting H&S culture in the Gulf region, significant gaps remain. These gaps highlight the need for additional investigation into the impact of H&S culture, constrained by limited time and resources.

Design/methodology/approach

Using a content analysis method, 18 previous studies were thoroughly reviewed to identify the main themes and areas requiring further improvement.

Findings

The findings of this study suggest that enhancing the understanding and implementation of H&S practices provide significant implications for leaders and organizations in the GCC. Effective strategies to improve workplace safety and employee retention are crucial. The study underscores the necessity for GCC leaders to actively drive the H&S agenda, emphasizing that a robust H&S culture is essential for reducing turnover and fostering a safer, more productive work environment.

Originality/value

Despite substantial research into issues such as the lack of training, workforce diversity and employee engagement in promoting H&S culture in the Gulf region, significant gaps remain. These gaps highlight the need for additional investigation into the impact of H&S culture, constrained by limited time and resources.

Details

International Journal of Pharmaceutical and Healthcare Marketing, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1750-6123

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Article
Publication date: 14 June 2022

Rifati Dina Handayani and Triyanto

The research aims to explore prospective physics teachers' pedagogical knowledge (PK) through an online microteaching lesson study (OMLS).

285

Abstract

Purpose

The research aims to explore prospective physics teachers' pedagogical knowledge (PK) through an online microteaching lesson study (OMLS).

Design/methodology/approach

The study used a case study with eight prospective physics teachers. Various data sources are triangulated involving audiovisual meeting recording, documents from OMLS sessions, interviews, and observation.

Findings

OMLS can build and enhance the PK of prospective physics teachers. The stages and cycles encourage participants to collaborate, exchange ideas to design active learning in the lesson plan teaching practice and revise deficiencies for improvement. The trial, analysis, discussion and revision of lessons reduced prospective teacher cognitive discrepancy.

Research limitations/implications

This study has several limitations. First, the research only focuses on prospective physics teachers' PK with two cycles, limiting data collection and inaccuracies. Second, the data were taken qualitatively and from a relatively small group, so the findings are not generalizable.

Practical implications

Educational departments in higher education can implement and develop various MLS models according to the conditions of their respective students.

Originality/value

This study realizes higher education as a preparation place for prospective teachers' future careers as professional teacher candidates.

Details

International Journal for Lesson & Learning Studies, vol. 11 no. 3
Type: Research Article
ISSN: 2046-8253

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