Radiative Boundary Layer Flow of Casson Fluid Over an Exponentially Permeable Slippery Riga Plate with Viscous Dissipation

This study is aimed to analyze the steady of stagnation point flow and radiative heat transfer of a non-Newtonian fluid which is Casson fluid passing over an exponentially permeable slippery Riga plate in presence of thermal radiation, magnetic field, velocity slip, thermal slip, and viscous dissipation effects. The governing partial differential equations are transformed into ordinary differential equations by using similarity transformation then solved numerically by boundary value problem solver (BVP4C) in MATLAB software package. The numerical results are evaluated with previous researches to reach an agreement with the parameters of the current study. This study is discussing the behavior of the velocity and temperature profiles as well as skin friction coefficient and local Nusselt number for various physical parameters such as magnetic field, radiation, suction, thermal slip, velocity slip, Prandtl number, Eckert number and modified Hartmann number. Numerical results are shown graphically for each parameter with different values. It is found that the momentum boundary layer thickness increases with increasing the values of Casson parameter. The temperature decreases when the velocity slip parameter and thermal slip parameter are increased.

Postharvest quality and storage life of Kuini (Mangifera Odorata Griff) at different storage temperature

Mangifera Odorata or locally called Kuini, is a mango species with attractive striking orange flesh and have strong and unique smell, make it special in local market. Research is being carried out in MARDI from seed production to marketing to expose M. odorata to local and export market. Postharvest handling technology is one of importance aspect that has been develop to cater the market needs for commercialization. Proper postharvest handling will reduce postharvest losses, maintain freshness and to prolong storage life to make sure consumer get the premium quality of fruit. In postharvest handling, one of most important factors to maintain quality during handling, distribution and display is storage at the optimum temperature. Effect of different storage temperature on quality and storage life of M. odorata var. Tembaga were carried out. M. odorata at 11 to 12 weeks after fruit set were harvest at MARDI Sintok, Kedah and transported to packinghouse MARDI Serdang for storage study. On arrival at MARDI Serdang, fruit were sorted, washed, drain, packed and stored at different storage temperature (8, 10, 13, 15 and 250C). Visual quality assessment (appearance, disease quality changes), physical (texture, colour (Lightness, hue, chroma)) and chemical (pH, total titratable acidity (TTA), ascorbic acid, soluble solid content (SSC)) analysis were carried out weekly. Results of this study showed that storage duration and different storage duration significantly affected SSC. pH, TTA, chroma of M. odorata. The highest TSS, pH and chroma of M. odorata at 100C and the lowest at 250C. The highest TTA of M. odorata at storage temperature 80C and 130C, and the lowest TTA at 250C. Ascorbic acid content not significantly affected by different storage temperature from 8 to 150C, but significant different compare to ascorbic acid content at ambient storage temperature. Ascorbic acid content of M. odorata significantly lower at 250C compare to storage at 8 C - 150C. Lightness and texture of M. odorata slightly decrease during storage but not significant (P>0.05). Lightness of M. Odorata was not significantly affected by different storage temperature. Hue of M. Odorata significantly affected by storage duration and but not affected by different storage temperature. Hue of M. odorata significantly increased in the first weeks of storage, followed by significant decreased at week 2, maintain until week 4 and significantly decreased at week 5. Quality observed visually showed that freshness of M. Odorata maintain 5 weeks at 80C, 4 weeks at 100C, 2 weeks at 10 – 150C and 1 week at 250C.

Mixing Chamber for Preparation of Nanorefrigerant

The last decade has seen the rapid advancement of nanofluid in several ways. Nanofluid based on the refrigerant have been introduced as nanorefrigerant in recent years due to their significant effects on the efficiency of heat transfer. Previous studies showed some limitation in ways of dispersing nanoparticles into refrigerant. Hence, a new idea of adding nanoparticles into refrigerant has been presented. A mixing chamber has been designed to mix nanoparticles into high pressure refrigerant. The mixing chamber design is drawn with five different wall thickness which are 2 mm, 4 mm, 6 mm, 8 mm and 10 mm to investigate the sturdiest design that can withstand high pressure. Static structural analysis is performed to all designs with different wall thickness on SolidWorks Simulation. The maximum values of von Misses stress and displacement has been presented in this paper. Validation of the results are made by comparing the maximum values of von Mises stress with yield strength of the material. Mixing chamber with wall thickness of 10 mm showed the best results.

The Green Logistics Idea Using Vacuum Insulation Panels (VIPs) For Freezer Logistics Box in Normal Truck

This research presents the green logistics using vacuum insulation panels (VIPs) for freezer logistics box in normal trucks. The materials were Vacuum Insulation Panels (VIPs) with polyurethane foam box compared to polyurethane foam box that thermal conductivity for polyurethane foam and Vacuum Insulation Panels (VIPs) at > 20 and < 7 mW/m.K. The vacuum Insulation Panels (VIPs) with polyurethane foam box design with VIP inside the polyurethane foam protect some impact from losing vacuum that loss thermal resistance. According to the result, after 24 hours, the ice-cream temperature of polyurethane foam box that lost 6 Degree Celsius, calculated as 30.00%. Besides, the ice-cream temperature of that vacuum Insulation Panels (VIPs) with a polyurethane foam box has lost 1.5 Degrees Celsius, counted as 7.5%, and compared with stating temperature at -20 Degrees Celsius. The result represents ice-cream quality after testing that shows the ice-cream condition in VIP Box still freezing, and ice cream condition in the normal box is melt. This research can be applied to a cold room or freezer room in supermarkets, factories, distribution centers, and VIPs that can result from electricity saving for compressors or cold trucks and freezer trucks that can get the result of fuel-saving for engines.

MHD Flow and Heat Transfer of Double Stratified Micropolar Fluid over a Vertical Permeable Shrinking/Stretching Sheet with Chemical Reaction and Heat Source

The present study analyses the magnetohydrodynamic (MHD) flow of a double stratified micropolar fluid across a vertical stretching/shrinking sheet in the presence of suction, chemical reaction, and heat source effects. The governing equations in the form of partial differential equations are transitioned into coupled nonlinear ordinary differential equations by means of similarity transformation. The numerical solutions are obtained with the aid of the boundary value problem bvp4c solver in the MATLAB software. Numerical results have been confirmed with the previous results for a certain case and the comparison is found to be in an excellent agreement. Results for related profiles and heat transfer characteristics are displayed through plots and tabulated for the governing parameters involved. It is found that the reduced skin friction coefficient and the local Nusselt number increase with the increasing chemical reaction and heat source parameters. The rising values of the chemical reaction parameter have increased the magnitude of the local Sherwood number. In contrary, the heat source parameter has the tendency to decrease the magnitude of the local Sherwood number.

Study on The Factors and Effects of Noise Pollution at Construction Site in Klang Valley

Noise Pollution is the high intensity of sound that is unnecessary and will cause harmful or danger towards human or nearby ecosystem. However, the occurrence of noise pollution is getting worse due to the process of country development. Noise pollution at construction site has become one of the noise pollution contributors in urban area where development in keep on going with the needs of construction projects. Area of study had been targeted at Klang Valley, Malaysia since it was one of the developing areas that consist huge amount of construction projects. Noise pollution produced at construction site is harmful to the health of those who involved in the construction projects and stay at the site for a long period of works. Thus, the main objectives of this study are to determine the factor of noise pollution at construction site and the effects of the noise towards those parties who involve such as engineer, contractor etc. The solutions to prevent or decrease the noise pollution at construction site were determined to help reducing its bad effects. Approximately 60 respondents had been collected in this survey to determine the most significant factor, effect and solution for noise pollution at construction site around Klang Valley. Based on the finding of this study, the significant factor caused noise pollution at construction site is due to heavy machinery operating. Respondents agreed that the noise pollution major affect is sleep disturbance. The significant solution against noise pollution at construction site is by applying muffler or silencer on construction machinery and equipment.

A Brief Review of Particle Dispersion of Cavity Flow

Particles dispersion studies have attracted researchers' interest in understanding the physics behind the phenomena. Fluid-particle transport related to cavity flow is relevant to several natural and engineering applications such as cleaning of process equipment. This paper intends to provide a brief review of researches on the impact parameters, including geometrical parameters of the cavities, flow-related parameters, heat transfer and fluid-particles interaction and identifies opportunities for future research.

Nanorefrigerants: A Review on Thermophysical Properties and Their Heat Transfer Performance

The last decade has seen the rapid enhancement of nanofluid in several ways. Nanofluid with refrigerant base have been introduced as nanorefrigerant in recent years due to their significant effects on the efficiency of heat transfer. A brief review of past studies on nanorefrigerants and their performance in thermodynamics and heat transfer area are reported in this paper. Some current challenges and future prospect of nanorefrigerant will also be highlighted.

Improving Energy Efficiency in the Supermarket by Retrofitting Low E Glass Doors for Open Refrigerated

This research presents the improving energy efficiency by retrofitting doors for open refrigerated in central Thailand supermarkets that open in the daytime (06.00 am - 6:00 pm) and close in night-time (00.00 am – 6:00 am). The Materials and Methods were open refrigerated 15 cabinet and retrofitting doors for open refrigerated that 41 frames, 82 doors in medium temperature refrigeration system and measure power consumption kW, kWh by power meter data logger for analysis and summarize. The power consumption saving average per 7 days for retrofitting doors was 576 kWh/day, 39.67% that daytime 418 kWh/day, 41.93%, and night-time 116 kWh/day, 33.24%. Besides, the energy of day time more than night time because 1) The time of opening store is longer than closing store 2) In the night time, the refrigerated will close by plastic curtain 3) The request cooling load of day time is longer than day time 4) The sale area/ambient temperature of night time more than day time but the humidity was contrasted. Before retrofitting doors, the maximum and minimum of power consumption was 83.25 kw/hour and 44.73 kw/hour, respectively. Also, the power consumption swing at 38.52 kw/hour, 46.72%, and the maximum and minimum of power consumption after retrofitting doors was 33.15 kw/hour and 30.19 kw/hour, respectively. The power consumption swing at 2.96 kw/hour, 8.93%. In addition, the power consumption swing will after be retrofitting doors will less than before retrofitting doors by 1) The average cooling load will be the same as bolt conditions 2) The request cooling load of doors refrigerated will less than by product load, the swing of sale area temperature and humidity, customer behavior that effect power condition will have the low running operation. This research's investment was 21,694 €, while the payback period of this research was 14 months. Besides, within 1.1 years, that energy saving was 16,020 kWh/Month or 1,542 €/Month, 16,020 kWh/month or 192,220 kWh/Year or 18,503 €/Year.

COVID-19 Outbreak in Malaysia: Investigation on Fatality Cases

The COVID-19 pandemic has affected the lives of millions across the globe and taken away hundreds of thousands of lives. The spread of COVID-19 due to negligence had caused thousands of confirmed cases in Malaysia. Malaysia Government enforced Movement Control Order as a measure to prevent further outbreak of the disease. This study investigated the current situation of COVID-19 in Malaysia and patients’ demographical connections to the disease. The findings show that COVID-19 attacked males more than females and the elderly of sixty years and above are mostly affected.