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  1. Thapa S, Zaki SA
    J Therm Biol, 2024 Feb;120:103809.
    PMID: 38364574 DOI: 10.1016/j.jtherbio.2024.103809
    The sub-Himalayan region extends over 2500 km, extending over several countries. Though the effects of climate change is widely anticipated in the diverse but fragile ecosystem of the Himalayas, very less research has been conducted on the indoor environment of the buildings in these regions. In this study, a pre-validated model of 3-storey concrete residential building was used to study the indoor performance and thermal comfort in the face of climate change in the 8 (eight) different hill towns (hill stations) located from west to the east. Rise in ambient and indoor conditions were evident as a part of climate change with colder locations being affected the most. The thermal comfort assessment using both the climate chamber based PMV model and adaptive models revealed the decrease in cold related discomfort and increase in hot related discomfort. On an overall, the indoor conditions improved in these cold locations. The indoor and outdoor thermal condition and thermal comfort plummeted significantly with latitude and elevation. The heating demand in the future climate reduced by about 50-70 % in warmer locations, while the cooling demand increased by as much as 1000-2000 % in cold locations, respectively. Additionally, it was seen that the thermal environment and comfort both declined more rapidly with elevation in the locations lying in the western Himalayas as compared to those in the eastern Himalayas.
  2. Zaki SA, Shaikh MG, Rashid A
    Malays Fam Physician, 2022 Nov 30;17(3):149-152.
    PMID: 36606170 DOI: 10.51866/cr.93
    Diabetic ketoacidosis (DKA) is a life-threatening complication of type 1 diabetes mellitus in children. Despite the presence of dehydration, hypertension occurs in a significant proportion of children with DKA. There is a lack of clarity in the literature regarding the management of hypertension in patients with paediatric DKA. Herein, we report the case of an adolescent boy who presented with DKA and severe hypertension. His neurological status was closely monitored. There was a gradual decline in his blood pressure with an improvement in the pH over the next 72 hours. The combination of severe DKA and hypertension can be a challenging clinical dilemma, especially regarding fluid management. Studies on severe DKA in children are exacting, given the rarity of this condition. A multi-centre study is suggested to provide a meaningful analysis of this aspect of DKA.
  3. Toosty NT, Hagishima A, Bari W, Zaki SA
    Sustain Prod Consum, 2022 Mar;30:608-622.
    PMID: 35013713 DOI: 10.1016/j.spc.2022.01.001
    Remote work (working from home) became a norm rather than an exception for the global workforce during the COVID-19 pandemic, influencing every facet of life in both positive and negative ways. The stringent action of the Malaysian government in enacting the Movement Control Order (MCO) motivated the investigation of its impact on the energy consumption behaviour of working people regarding air-conditioner (AC) use. To this end, this study conducted a cross-sectional survey through an online platform. An ordinal logistic regression model (ORL) was used to analyse the collected data of 1873 respondents to determine the factors influencing the ordinal variable of interest, AC-usage behaviour during remote work. Next, the variable with unordered categories, the MCO-induced change in AC-usage behaviour, was analysed using a multinomial regression model (MLT) to identify the potential determinants. Finally, a reason analysis unveiled aspects behind the transition in AC use during remote work. This study identified stopping AC use during remote work despite using it at the office before the MCO period as the most significant change in AC-usage behaviour due to MCO. This change was frequently adopted by people with medium-level incomes and high electricity bills. By contrast, participants unfamiliar with their electricity bill were most likely to start AC use during remote work, although they did not use it before the MCO. Participants working remotely in the communal spaces of their houses preferred to stop using ACs during MCO compared to private room users. Furthermore, age group and ethnicity significantly influenced AC-usage behaviour in remote work and changes in such demeanours. These findings recommend policy interventions to expedite limited AC use for a sustainable energy sector, even during future climatic emergencies .
  4. Othman NE, Zaki SA, Rijal HB, Ahmad NH, Razak AA
    Int J Biometeorol, 2021 Apr;65(4):453-477.
    PMID: 33416948 DOI: 10.1007/s00484-020-02035-3
    Difficulties in controlling the effects of outdoor thermal environment on the human body are attracting considerable research attention. This study investigated the outdoor thermal comfort of urban pedestrians by assessing their perceptions of the tropical, micrometeorological, and physical conditions via a questionnaire survey. Evaluation of the outdoor thermal comfort involved pedestrians performing various physical activities (sitting, walking, and standing) in outdoor and semi-outdoor spaces where the data collection of air temperature, globe temperature, relative humidity, wind speed, solar radiation, metabolic activity, and clothing insulation data was done simultaneously. A total of 1011 participants were interviewed, and the micrometeorological data were recorded under outdoor and semi-outdoor conditions at two Malaysian university campuses. The neutral temperatures obtained which were 28.1 °C and 30.8 °C were within the biothermal acceptable ranges of 24-34 °C and 26-33 °C of the PET thermal sensation ranges for the outdoor and semi-outdoor conditions, respectively. Additionally, the participants' thermal sensation and preference votes were highly correlated with the PET and strongly related to air and mean radiant temperatures. The findings demonstrated the influence of individuals' thermal adaptation on the outdoor thermal comfort levels. This knowledge could be useful in the planning and designing of outdoor environments in hot and humid regions to create better thermal environments.
  5. Norhasnan NHA, Hassan MZ, Nor AFM, Zaki SA, Dolah R, Jamaludin KR, et al.
    Polymers (Basel), 2021 Apr 06;13(7).
    PMID: 33917337 DOI: 10.3390/polym13071171
    Utilizing agro-waste material such as rice husk (RH) and coco peat (CP) reinforced with thermoplastic resin to produce low-cost green composites is a fascinating discovery. In this study, the effectiveness of these blended biocomposites was evaluated for their physical, mechanical, and thermal properties. Initially, the samples were fabricated by using a combination of melt blend internal mixer and injection molding techniques. Increasing in RH content increased the coupons density. However, it reduced the water vapor kinetics sorption of the biocomposite. Moisture absorption studies disclosed that water uptake was significantly increased with the increase of coco peat (CP) filler. It showed that the mechanical properties, including tensile modulus, flexural modulus, and impact strength of the 15% RH-5% CP reinforced acrylonitrile-butadiene-styrene (ABS), gave the highest value. Results also revealed that all RH/CP filled composites exhibited a brittle fracture manner. Observation on the tensile morphology surfaces by using a scanning electron microscope (SEM) affirmed the above finding to be satisfactory. Therefore, it can be concluded that blend-agriculture waste reinforced ABS biocomposite can be exploited as a biodegradable material for short life engineering application where good mechanical and thermal properties are paramount.
  6. Maruai NM, Ali MSM, Zaki SA, Ardila-Rey JA, Ishak IA
    Sci Rep, 2023 Oct 17;13(1):17681.
    PMID: 37848600 DOI: 10.1038/s41598-023-44388-w
    The investigations of flow-induced vibration have been around for decades to solve many engineering problems related to structural element. In a hindsight of advancing technology of microelectronics devices, the implementation of flow-induced vibration for energy harvesting is intrigued. The influence of downstream flat plate to flow-induced vibration experienced by a square cylinder is discussed in this study to surpass the limitation of wind energy due to geographical constraints and climate change. The mechanism of flow-induced vibration experienced by a square cylinder with downstream flat plate is numerically simulated based on the unsteady Reynolds Navier-Stokes (URANS) flow field. The Reynolds number, Re assigned in this study is ranging between [Formula: see text]-[Formula: see text] and the mass damping ratio designated for the square cylinder is [Formula: see text] = 2.48. The influence of three different flat plate lengths [Formula: see text], 1 and 3 is examined. Each case of different flat plate is explored for gap separation between the square cylinder and the plate in the range [Formula: see text]. Based on the numerical findings, the configuration of cylinder-flat plate with length [Formula: see text] has shown the highest potential to harvest high energy at comparatively low reduced velocity.
  7. Haris NIN, Ilyas RA, Hassan MZ, Sapuan SM, Afdzaluddin A, Jamaludin KR, et al.
    Polymers (Basel), 2021 Sep 29;13(19).
    PMID: 34641159 DOI: 10.3390/polym13193343
    This study investigates the mechanical, thermal, and chemical properties of basalt/woven glass fiber reinforced polymer (BGRP) hybrid polyester composites. The Fourier transform infrared spectroscopy (FTIR) was used to explore the chemical aspect, whereas the dynamic mechanical analysis (DMA) and thermomechanical analysis (TMA) were performed to determine the mechanical and thermal properties. The dynamic mechanical properties were evaluated in terms of the storage modulus, loss modulus, and damping factor. The FTIR results showed that incorporating single and hybrid fibers in the matrix did not change the chemical properties. The DMA findings revealed that the B7.5/G22.5 composite with 7.5 wt% of basalt fiber (B) and 22.5 wt% of glass fiber (G) exhibited the highest elastic and viscous properties, as it exhibited the higher storage modulus (8.04 × 109 MPa) and loss modulus (1.32 × 109 MPa) compared to the other samples. All the reinforced composites had better damping behavior than the neat matrix, but no further enhancement was obtained upon hybridization. The analysis also revealed that the B22.5/G7.5 composite with 22.5 wt% of basalt fiber and 7.5 wt% of glass fiber had the highest Tg at 70.80 °C, and increased by 15 °C compared to the neat matrix. TMA data suggested that the reinforced composites had relatively low dimensional stabilities than the neat matrix, particularly between 50 to 80 °C. Overall, the hybridization of basalt and glass fibers in unsaturated polyester formed composites with higher mechanical and thermal properties than single reinforced composites.
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