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The purpose of this paper is to numerically study the phenomenon of separation and subsequent reattachment that happens due to a sudden contraction or expansion in flow geometry, in addition, to investigating the effect of nanoparticles suspended in water on heat transfer enhancement and fluid flow characteristics.

Turbulent forced convection flow over triple forward facing step (FFS) in a duct is numerically studied by using different types of nanofluids. Finite volume method is employed to carry out the numerical investigations. with nanoparticles volume fraction in the range of 1-4 per cent and nanoparticles diameter in the range 30-75 nm, suspended in water. Several parameters were studied, such as the geometrical specification (different step heights), boundary conditions (different Reynolds [Re] numbers), types of fluids (base fluid with different types of nanoparticles), nanoparticle concentration (different volume fractions) and nanoparticle size.

The numerical results indicate that the Nusselt number increases as the volume fraction increases, but it decreases as the diameter of the nanoparticles of nanofluids increases. The turbulent kinetic energy and its dissipation rate increase as Re number increases. The velocity magnitude increases as the density of nanofluids decreases. No significant effect of increasing the three steps heights on Nusselt along the heated wall, except in front of first step where increasing the first step height leads to an increase in the recirculation zone size adjacent to it.

The phenomenon of separation and subsequent reattachment happened due to a sudden contraction or expansion in flow geometry, such as forward facing and backward facing steps, respectively, can be recognized in many engineering applications where heat transfer enhancement is required. Some examples include cooling systems for electronic equipment, heat exchanger, diffusers and chemical process. Understanding the concept of these devices is very important from the engineering point of view.

Convective heat transfer can be enhanced passively by changing flow geometry, boundary conditions, the traditional fluids or by enhancing thermal conductivity of the fluid. Great attention has been paid to increase the thermal conductivity of base fluid by suspending nano-, micro- or larger-sized particles in fluid. The products from suspending these particles in the base fluid are called nanofluids. Many studies have been conducted to investigate the heat transfer and fluid flow characteristics over FFS. This study is the first where nanofluids are employed as working fluids for flow over triple FFS.

The present study aims to evaluate the effect of climate change on the flood hazard potential in the Kelantan River Basin using current and future scenarios.

The intensity-duration-frequency (IDF) was used to estimate the current 50- and 100-year return period 24-h design rainfall, and the climate change factor (CCF) was used to compute the future design rainfall. The CCF was calculated from the rainfall projections of two global climate models, CGCM1 and CCSM3, with different pre-processing steps applied to each. The IDF data were used in the rainfall-runoff-inundation model to simulate current and future flood inundation scenarios.

The estimated CCF values demonstrate a contrast, whereby each station had a CCF value greater than one for CGCM1, while some stations had a CCF value of less than one for CCSM3. Therefore, CGCM1 projected an aggravation and CCSM3 a reduction of flood hazard for future scenarios. The study reveals that topography plays an essential role in calculating the CCF.

To the best of the author’s knowledge, this is the first study to examine flood projections in the Kelantan River Basin. It is, therefore, hoped that these results could benefit local managers and authorities by enabling them to make informed decisions regarding flood risk mitigation in a climate change scenario.

The purpose of this study is to know the influence of palm oil fuel ash and metakaolin on the strength of concrete and crack resistance of reinforced concrete beam. An ordinary portland cement has been used in the concretes production where it is an important material to be considered due to its nature that reacts with every substance present. During the cement production, a significant amount of carbon dioxide is emitted from the clinker in rotary kiln and lot of energy is required in the production processes. Such an event can be prevented by replacing the part of cement with metakaolin (MK) and palm oil fuel ash (POFA). Aside from being a cementitious alternative, the materials can also contribute to a greener environment and more sustainable building, as POFA is available in Malaysia and may be used to substitute cement and minimize pollution.

This study assesses the effect of MK and POFA on the concrete in terms of compressive strength and cracks pattern of the reinforced concrete beam based on the relevant previous studies.

From this study, the compressive strength of concrete containing MK and POFA was higher than the control mix with the percentage of improvement in the range of 0.8%–78.2% for MK and 0.5%–14%, respectively. The optimum content of MK and POFA is between the range of 10% and 15% and 10% and 20%, respectively, to achieve high strength of concrete. Other than that, the inclusion of MK to the concrete mix improves the strength of reinforced concrete beams and reduces cracks on the surface of reinforced concrete beams, whereas the inclusion of POFA to the concrete mix increases the cracks on reinforced concrete beams. The cracks appeared within the flexure zone of every beam containing the MK and POFA.

It was found that the fineness of MK and POFA has a significant influence on the mechanical properties of concrete.

The purpose of this study was to explore patient’s perception of their disorder.

This study used a phenomenographical approach within a qualitative research paradigm. A total of 21 patients with knee osteoarthritis (OA) were recruited for the study, and data were collected through open-ended face-to-face interviews. The interviews were transcribed and thematically analyzed. The transcribed verbatim was analyzed for themes.

The themes developed reflected the patients’ perceptions about the disease process. Thematic analysis revealed three themes: Knee OA is a degenerative disease, Knee OA is an age-related disease and Knee OA is caused by certain activities of daily living. The patient’s information varied and was limited to what had been provided by the health-care practitioner. The knowledge was more biomedical in orientation and was limited and not supported by the evidence.

There is a need to provide evidence-based information that the patient must understand. Health-care providers must use a biopsychosocial framework to discuss the disease knowledge with patients.

This study helps us in identifying disease perceptions that can be used to design education programs for knee OA patients. It also highlights the need for delivering educational programs to knee OA patients.

This study lays a foundation for further research. To the author’s best knowledge, this is the first study to explore disease perceptions using a qualitative approach conducted among patients from a lower middle-income country.

The study aims to explore how lean research and development (R&D) tools and techniques (T&T: i.e. R&D hard practices) affect the relationship between lean R&D soft practices and organization performance within R&D-based manufacturing firms in Malaysia.

The current study is a quantitative study that utilized an online survey questionnaire for data collection. Data were collected based on a cross-sectional survey of R&D managers from 102 R&D-based manufacturing firms in Malaysia. Structural equation modeling (SEM) was used to test the impact of lean R&D soft and hard practices on firms' performance.

As per the study findings, it was determined that T&T of lean R&D was significant mediator in the relationship between lean R&D soft practices (i.e. managerial practices, transformational leadership, financial capability and supplier involvement) and R&D firms' performance.

The study delivers an important message to R&D companies that lean practices could be applied in R&D environments to drive organization performance.

The study extends the knowledge regarding lean principles and framework beyond the domains of production and services. The study offers new conceptual contribution in term of lean principles and framework in R&D environments by introducing the role of lean R&D tools and technique to enhance the effects of lean R&D practices on organization performance.