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The requirement of hydrogen in the transport system is indispensable nowadays. Especially to fulfill the requirement from the transports and industry sector related with green technology implementation. As an alternative, a research has been conducted from a technical aspect on the profitability of using hydrogen onboard as fuel for internal combustion engine. Applications using a mixture of Gasoline with hydrogen (G+H2) can be used to increase the combustion performance especially on the reduction of hydrocarbon and carbon monoxide. In this study hydrogen as an alternative fuel in four-stroke motorcycles has been tested using a chassis dynamometer model ATV Inertial Dyno, 054-500-1K. Hydrogen requirement in the petrol mixing ratio is dependent on the operating system of the engine ignition system which is controlled by hydrogen pressure in the cylinder. Three stages of load test on the engine performance have been conducted on the chassis dynamometer, namely, load test L0 is equal 0 ampere (L0), load test L1 is equal 1 ampere, and load test L2 is equal 2. During the tests L0, L1 and L2, the average hydrocarbon gas readings decreased by 34 % and 58.2% (L0), 27.4% (L1) and 16.7% (L2) to 46ppm, 85ppm and 95ppm respectively versus gasoline engine 110ppm, 117ppm and 114ppm. And the overall average results of this study showed a reduction of carbon monoxide by 33 %. It proves the use of hydrogen (AL + HCl) in the stoichiometric ratio helps combustion when the oxygen content in the air and fuel mixture is not adequate especially for vehicles using gasoline as a fuel.

Hospital energy consumption is relatively high, while saving energy and reducing cost comprise one of the most important challenges considered by the majority of building designers, engineers, and decision makers. An end-use energy analysis was conducted in a large-scale hospital in Malaysia to identify energy apportioning and energy end use in the areas of air conditioning, lifts, lighting, equipment, and others. The analysis was carried out by assessing the collected desktop and field data as well as some calculations. The Building Energy Index (BEI) was calculated to compare the consumption levels in the selected hospital, which is a typical hospital building, with other hospitals in Malaysia as well as low energy buildings and Malaysian standards. The main energy source in this case study was electricity with a supply of around 75 % of total energy consumption. The current average annual electricity consumed by this hospital was 44,637,966 kWh, out of which 63 % was used by air conditioning systems and 17 % by lighting. The BEI comparison revealed that the calculated BEI of 384 kWh/m2/year is significantly higher than Malaysian rating systems and standards which recommend 200 kWh/m2/year for hospitals, 135 kWh/m2/year for commercial sectors, and is higher than previously observed hospitals with a BEI of less than 300 kWh/m2/year.

A review on graphene geopolymers hybrid is presented, focusing on the mechanical properties and piezoelectric effect. The method and way of mixing graphene with geopolymers are discussed, including form of graphene that frequently being used by researchers which is graphene oxide (GO) and reduced graphene oxide (rGO). Type of geopolymers being focused in this paper is fly ash and kaolin. The flexural and compressive strength, fracture toughness and stiffness are highlighted in terms of mechanical properties after mixing with geopolymers. The piezoelectric effects on geopolymer is emphasized as graphene acted as conductive filler. Research findings revealed that graphene geopolymer hybrid displayed improvement in mechanical properties despite agglomeration and some defects that need to be rectified. Geopolymers such as metakaolin exhibited piezoelectric effect after being compressed cyclically with the migration of ions and by incorporating graphene nanoplateletes.

This study enveloped an innovative uses of banana peel particles (BPP) incorporated with recycle aggregate concrete (RAC) from construction waste as an artificial concrete reef for estuarine ecosystem. An artificial reef concrete composites were made of using BPP reinforced RAC as a matrix. The conretes composite cube were prepared in a percentages of 10%, 20% and 30% of BPP to RAC respectively. The concrete cubes without BPP was used as control cubes. The compressive strength of an artificial reef concretes composites were carried out at 28 days. The total nutrient dispersed were determined using total nitrate (TN), phosphorus (TP) and organic carbon (TOC) test of the water samples in 6 days. The results showed that the averages compressive strength were 26.8 MPa for 10% of BPP, 18.3 MPa for 20% of BPP and 11.MPa for 30% of BPP, respectively. The amount of TN, TP and TOC leached from the articial concrete reef ranged from 34.3% to 41.5%, 58.2% to 70.3%, and 7.2% to 10.6%, respectively. It also reported that the amount of nutrients leached from an artificial reef increased gradually with time as more percentages of BPP added to concrete composites and on the contrary, the compressive strength indicated decreases with the increased of BPP. Wet can be concluded that, BPP from the agriculture wastes could be used as potential nutrient sources of nitrogen, phosphorus and organic carbon for an artificial concrete reef in estuarine ecosystem with some further study on mechanical properties to increase the compressive strength of an artificial reef composite concretes.

Oil and gas today being developed at different water depth characterized as shallow, deep and ultra-deep waters. Among the major components involved during the offshore installation is pipelines. Pipelines are a transportation method of material through a pipe. In oil and gas industry, pipeline come from a bunch of line pipe that welded together to become a long pipeline and can be divided into two which is gas pipeline and oil pipeline. In order to perform pipeline installation, we need pipe laying barge or pipe laying vessel. However, pipe laying vessel can be divided into two types: S-lay vessel and J-lay vessel. The function of pipe lay vessel is not only to perform pipeline installation. It also performed installation of umbilical or electrical cables. In the simple words, pipe lay vessel is performing the installation of subsea in all the connecting infrastructures. Besides that, the installation processes of pipelines require special focus to make the installation succeed. For instance, the heavy pipelines may exceed the lay vessel's tension capacities in certain kind of water depth. Pipeline have their own characteristic and we can group it or differentiate it by certain parameters such as grade of material, type of material, size of diameter, size of wall thickness and the strength. For instances, wall thickness parameter studies indicate that if use the higher steel grade of the pipelines will have a significant contribution in pipeline wall thickness reduction. When running the process of pipe lay, water depth is the most critical thing that we need to monitor and concern about because of course we cannot control the water depth but we can control the characteristic of the pipe like apply line pipe that have wall thickness suitable with current water depth in order to avoid failure during the installation. This research will analyse whether the pipeline parameter meet the requirements limit and minimum yield stress. It will overlook to simulate pipe grade API 5L X60 which size from 8 to 20mm thickness with a water depth of 50 to 300m. Result shown that pipeline installation will fail from the wall thickness of 18mm onwards since it has been passed the critical yield percentage.

This research focused on development of wearable sensor device by using Prevulcanized Natural Rubber (PV) and Epoxidized Natural Rubber (ENR 50) latex incorporated with graphene oxide (GO), graphene paste, graphene powder and reduced graphene oxide (rGO) powder. The compounding formulation and calculation were based on phr (parts per hundred rubber) and all the samples were then tested for mechanical properties using Instron 5565 machine. It was found that the sonication effects on tensile strength may have better quality of tensile strength compared to non-sonicated GO. For PV incorporate GO, the optimum loading was best determined at loading 1.5 phr with or without sonication and similar result was recorded for PV/G. For ENR 50 incorporate graphene paste and rGO powder nanocomposite shows the best optimum was at 3.0 phr with 24 hours' sonication.

To develop new drying facilities, it was important to know the impact of every input parameter to the drying process. Using a real prototype to carry out the experiment required high cost and time consuming especially for large scale drying. CFD simulation approached was one of the solution. Previous study of drying simulation only focuses on the fix value of the input parameter. This paper presents the result of CFD simulation to predict the heat distribution in sericite mica drying with variable temperature and airflow condition. Variable temperature and airflow was used because the only heat source for the dryer was from the solar energy therefore it's only available in the day time. The analysis was carried out for 24 hours of drying time. The simulation result shows that the temperature inside the sericite mica increase 8 to 10degC when the solar energy is available and it is still increasing about 4 to 7degC for 5 hours after the solar energy is absent. The result also shows that during the drying time the temperature of sericite mica that is closer to the heat source was higher compared to the one that is further away with the maximum difference of 3.8degC.

New group of materials derived from hybridization of single walled carbon nanotubes (SWCNTs) and graphene oxide (GO) which resulting novel three dimensional (3D) materials generates an outstanding properties compared to corresponding SWCNTs and GO/Graphene. In this paper, we describe a simple approach using water processing method to develop integrated rGO/GO-SWCNT hybrids with different hybrid ratios. The hybrid ratios were varied into three divided ratio and the results were compared between pristine SWCNTs and GO in order to investigate the structural density and morphology of these carbonaceous materials. With an optimized ratio of rGO/GO-SWCNT, the hybrid shows a well-organized hybrid film structures with less defects density sites. The optimized mixture ratio emphasized the important of both rGO and SWCNTs in the hybrid structures. Morphological structural and defects density degrees were examined by Field Emission Scanning Electron Microscopy (FESEM) and Raman spectroscopy.

This paper presents the experimental results from the investigation carried out at the UTM Low Speed wind tunnel facility (UTM-LST) on a half model generic transport aircraft at several configurations of primary control surfaces (flap, aileron and elevator). The objective is to measure the aerodynamic forces and moments due to the configuration changes. The study is carried out at two different speeds of 26.1 m/s and 43.1 m/s at corresponding Reynolds number of 1 x 106 and 2 x 106, respectively. Angle of attack of the model is varied between -2o to 20o. For the flaps, the deflection applied is 0o, 5o and 10o. Meanwhile, for aileron and elevator, the deflection applied is between -10o and 10o. The results show the differences in aerodynamic characteristics of the aircraft at different control surfaces configurations. The results obtained indicate that a laminar separation bubble developed on the surface of the wing at lower angles of attack and show that the separation process is delayed when the Reynolds number is increased.

Wing in-ground effect (WIG) crafts are becoming promising transportation over the last decade. However, stability and control problems faced by the WIG in earlier development are still unresolved. This paper objectively investigates the lateral stability of wing in ground effect craft. The wing encompasses a winglet at the end of the wingtip. Lift, drag and pressure were measured with the respect of the heeling angle of 100, 150 and 200, respectively, with the h/c of 0.3. Initial results from the computational studies show that the ground effect pressure distributions provide a natural righting moment when the WIG craft heels near ground. This initial result provides an insight to understand the current state of knowledge of stability for WIG, particularly on transverse or lateral stability of WIG where it plays important roles in the safety aspect. It is crucial to understand the stability and its component in order to avoid any unforeseen accident. This paper discusses the results obtained from the numerical studies.

An improved system of the new combined single stage absorption cycle operated with NH3/H2O as working fluid was performed. In order to enhance performance the cycle a new configuration of absorption system was utilized. The performances of two configurations of the combined absorption cycle were compared; a) with common solution heat exchanger and b) divided the streamline of solution heat exchanger to recover the internal heat. Based on the analysis, it has been shown that the second configuration a significant reduction of the required generator and absorber loads by about 20% and 17% respectively, with increased coefficient of performance (COP) about 12% compared to the first configuration. This improvement in the overall COP is found due to improve energy utilization efficiency significantly.

Nanofluids for improve characteristics flow in a rib-groove channel are investigate. The continuity, momentum and energy equations were solved by FLUENT program. The bottom wall of channel is heated while the upper wall is symmetry, the left side velocity inlet, and the right side is outlet (pressure out). Four different rib-groove shapes are used. Four different types of nanoparticles, Al2O3, CuO, SiO2, and ZnO with different volumes fractions in the range of 1% to 4% and different nanoparticle diameter in the range of 25 nm to 70 nm, are dispersed in the base fluid water are used. In this paper, several parameters such as different Reynolds numbers in the range of 10000 < Re < 40000 are investigated. The numerical results indicate that the trapezoidal with increasing height in the flow direction rib- trapezoidal groove has the best heat transfer and high Nusselt number; the nanofluids with SiO2 have the best behavior. The Nusselt number increases as the volume fraction increases and it decreases as the nanoparticle diameter increases.

Nanofluids for improve characteristics flow in a rib-groove channel are investigate. The continuity, momentum and energy equations were solved by FLUENT program. The bottom wall of channel is heated while the upper wall is symmetry, the left side velocity inlet, and the right side is outlet (pressure out). Four different rib-groove shapes are used. Four different types of nanoparticles, Al2O3, CuO, SiO2, and ZnO with different volumes fractions in the range of 1% to 4% and different nanoparticle diameter in the range of 25 nm to 70 nm, are dispersed in the base fluid water are used. In this paper, several parameters such as different Reynolds numbers in the range of 10000 < Re < 40000 are investigated. The numerical results indicate that the trapezoidal with increasing height in the flow direction rib- trapezoidal groove has the best heat transfer and high Nusselt number; the nanofluids with SiO2 have the best behavior. The Nusselt number increases as the volume fraction increases and it decreases as the nanoparticle diameter increases.

Background: Rapid population aging occurring in developing nations necessitates innovation to ensure we continue to gain ground on aging research despite pandemic threats. While developed nations have resorted to virtual communications, this is challenging in developing nations due to poor internet connectivity and digital literacy., Objectives: The aim of this study was to determine the feasibility of virtual data collection for a longitudinal study of aging assessing cognitive frailty in a middle-income Southeast Asian country., Methods: The Transforming Cognitive Frailty into Later-Life Self-Sufficiency (AGELESS) longitudinal study of aging involved community-dwelling participants aged 60 years and above. A semi-structured focus group discussion was conducted via videoconferencing with selected representatives from existing participants. The survey instrument was compiled during a hybrid meeting and refined using a virtual Delphi process involving 51 AGELESS investigators. The final draft survey and recruitment strategy were then piloted among selected participants., Results: Twelve individuals participated in the virtual focus group interview. Smartphone, tablet computer, laptops, and desktop personal computers were used for information gathering, communication, banking, shopping, leisure, religion, and education, within this group. The survey instrument was redacted from 362 items in 18 sections to 141 items in 12 sections through 3 virtual Delphi rounds facilitated by email, social media messaging, and videoconferencing which attracted 213 comments. Of 45 participants selected for the pilot survey, 30 were successfully contacted after one attempt and 18 completed the survey. Cognitive frailty was present in 13%, cognitive impairment in 20%, frailty in 20%, and 47% were robust., Conclusion: A virtual survey instrument was developed for the AGELESS longitudinal survey of aging which was vital for determining the effects of the COVID-19 pandemic on our older population as well as sustaining research into aging despite barriers posed by the pandemic., (© 2021 S. Karger AG, Basel.)