Abdul Ghapar Ahmad
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Preferred name
Abdul Ghapar Ahmad
Official Name
Ahmad, Abdul Ghapar
Alternative Name
Ahmad, Abdul Ghapar
Ahmad, A.G.
Main Affiliation
Scopus Author ID
57192914392
Researcher ID
ENF-7604-2022

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Potential of pretreated palm kernel shell on pyrolysis

2023-01-01 , Razi Ahmad , Ragunathan Al Santiagoo , Abdul Ghapar Ahmad , Syakirah Afiza Mohammed , Wan Ahmad W.A.M. , Vikneswaran Vijean , Ibrahim N.R.

The impact of pretreatment on palm kernel shell (PKS) with torrefaction for the possibility of pyrolysis is discussed in this study. PKS samples were torrefied at different holding times of 30 and 60 minutes at temperatures of 200, 225, 250, 275, and 300 °C. In a fixed-bed reactor with a constant nitrogen flow rate of 500 ml/min, torrefaction pretreatment was carried out. The elemental composition, mass, and energy yield, as well as proximate analysis, were all performed on the pretreated PKS. The optimised pretreated PKS was pyrolyzed next at a temperature of 400 to 550 °C in a fixed-bed reactor. The outcomes demonstrated that the pretreated PKS had a significant mass and energy yield at a temperature of 250 °C and a holding time of 30 min. PKS's calorific value and carbon content both rose after pretreatment. However, the oxygen and moisture content decreased for pretreated PKS. The maximum bio-oil production of 58% was achieved during the pyrolysis of pretreated PKS at a temperature of 500 °C. At higher temperature of 550 ℃, the bio-oil decreased due to secondary cracking reaction. Consequently, the pretreated PKS has greater potential as effective feedstock for successive proses particularly pyrolysis for bio-oil production.

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Identification of habitual smokers through speech signal

2024-02-08 , Vikneswaran Vijean , Ragunathan Al Santiagoo , Abdul Ghapar Ahmad , Syakirah Afiza Mohammed , Razi Ahmad , Wan Amiza Amneera Wan Ahmad

Smoking is an addictive behavior and can result major health complications. Nowadays, many young adults tend to pick up this unhealthy habits which could potentially harm their health and affects the future workforce of the nation. Most of the habitual smokers have difficulties in ceasing this habit and require external assistance in the form of group therapy, medical interventions to quit smoking. Therefore, the main aim of this study is to investigate the speech signals of the subjects in an effort to identify the habitual smokers non-invasively. Through this detection, young smokers could be identified. Voice samples from VOice ICar fEDerico II from PhysioNet database were used for this study. Wavelet Packet Transform was used to extract non-linear features from the signals. Due to uneven data, ADASYN algorithm was used to produce a balanced dataset through synthetic data sampling. Subspace KNN and SVM classifiers were used for the investigations and classification accuracies up to 83.7% and 94% of AUC curve were observed from the analysis. The results suggests that the proposed method is effective in detecting habitual smokers, and can be considered as an early screening for smoking habits in young adults for targeted rehabilitation strategies.

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Investigation on Medicated Drugs in ECG of Healthy Subjects

2022-01-01 , Vikneswaran Vijean , Abdul Ghapar Ahmad , Syakirah Afiza Mohammed , Razi Ahmad , Wan Amiza Amneera Wan Ahmad , Ragunathan Al Santiagoo , Lim Chee Chin

Heart diseases are now the leading cause of death worldwide, it is estimated that around 7 million patients who are living in developed countries, lost their lives due to diseases related to their cardiovascular system. In Malaysia, cardiovascular diseases represents one fifth of total deaths in the country in the past three decades. Currently patients need some sort of drugs that help them to stabilize and restore the regular patterns of their heart beat because if the patients cannot manage to restore the normal heart beat pattern, the undesired heart condition could lead life threatening situations. Advancement of biotechnology has enabled the creation of new medicated drugs to provide better treatment options. However, when this treatment option fails and there is a need to provide emergency intervention to the patients in hospitals, the medical experts often need to know about the patients' intake of any medications prior to hospital admittance for providing suitable treatments. Sometimes, this would be a difficult task as the patient might be admitted in semi-conscious or unconscious state. Therefore, this study focusses on identification of different medicated drugs usage through analysis of ECG data of the users. The data for the experiment was obtained from physionet library, which provides ECG data of subjects administered with a combination of Dofetilide, Mexiletine, lidocaine, Moxifloxacin and Diltiazem medicated drugs. The use of morphological and non-linear features derived from the ECG signals were able to provide prediction accuracy of 77.26% using SVM classifier.

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Early Detection of Diabetic Foot Ulcers through Wearable Shoe Design

2022-01-01 , Vikneswaran Vijean , Syakirah Afiza Mohammed , Razi Ahmad , Wan Amiza Amneera Wan Ahmad , Ragunathan Al Santiagoo , Abdul Ghapar Ahmad , Palaniappan R.

Diabetes Mellitus is categorized as a chronic metabolic disease where blood glucose levels are abnormal. Diabetic foot ulcer is a complication often associated with this disease. Diabetes foot ulcer is also commonly known as diabetes foot pain. It is a type of foot damage medical condition that progresses from diabetes mellitus. According to scientific data, almost 15% of diabetes patients may develop diabetes foot ulcer in their lifetime [1]. A foot ulcer is an open wound that commonly found under the feet, it can be a shallow open wound on the surface of the skin (less severe) or it can be a deep wound which exposes bones, tendons and joints [2]. However, if early prevention is carried out, diabetes patients might be able to avoid problems from diabetes foot ulcer. Thus, in this study, a wearable shoe prototype for early detection of foot ulcers is proposed to be used in home. The developed device will be associated with temperature sensor, vibration motor and pressure sensor. This device enables diabetes patients to carry out evaluation on their foot in daily life. With this device, early symptoms of foot ulcer can be detected and the seriousness of foot ulcer can be monitored.

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Compatibilizers Effect on Recycled Acrylonitrile Butadiene Rubber with Polypropylene and Sugarcane Bagasse Composite for Mechanical Properties

2023-10-16 , Zainal M. , Ragunathan Al Santiagoo , Razi Ahmad , Mohammed S.A. , Abdul Ghapar Ahmad , Vikneswaran Vijean , Wan Amiza Amneera Wan Ahmad , Allan Melvin Andrew

Compatibilizers effect on recycled acrylonitrile butadiene rubber (NBRr) with polypropylene (PP) and sugarcane bagasse (SCB) composite for mechanical properties is evaluated. Trans-Polyoctylene Rubber (TOR) and Bisphenol a Diglycidyl Ether (DGEBA) are used as compatibilizers in this study. Three (3) different composites (80/20/15, 60/40/15, and 40/60/15), with fixed filler (15 phr) and compatibilizers (10 phr) content, were carried out. These composites were arranged via melt mixing technique utilizing a heated two-roll mill at a temperature of 180 C for 9 minutes employing a 15-rpm rotor speed. Tensile and morphological properties were evaluated. The result shown average tensile strength dropped by 48.50% as the recycle NBR content rises 20 phr. Nevertheless, subsequent compatibilization reveals that the compositesâ tensile properties were all greater than control composites. The morphology discovered validates the tensile properties, indicating a stronger interaction between the PP/SCB and recycle NBR composites with the addition of compatibilizer DGEBA.

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Cloud-based System for University Laboratories Air Monitoring

2020-09-21 , Abu Hassan Abdullah , Sukhairi Sudin , Mustafa M.H. , Fathinul Syahir Ahmad Sa'ad , Khairul Azwan Ismail , Muhammad Aizat Abu Bakar , Mohamed Elshaikh Elobaid Said Ahmed , Abdul Ghapar Ahmad , Zahari Awang Ahmad , Sara Yasina Yusuf

Indoor air such as house, shopping complex, hospital, university, office and hotel should be monitor for human safety and wellbeing. These closed areas are prone to harmful air pollutants i.e. allergens, smoke, mold, particles radon and hazardous gas. Laboratories in university are special room in which workers (student, technician, teaching/research assistants, researcher and lecturer) conduct their works and experiment. The activities and the environment will generate specific air pollutant which concentration depending to their parameters. Anyone in the environment that exposure to these pollutants may affect safety and health issue. This paper proposes a study of development of a cloud-based electronic nose system for university laboratories air monitoring. The system consists of DSP33-based electronic nose (e-nose) as nodes which measure main indoor air pollutant along with two thermal comfort variables, temperature and relative humidity. The e-noses are placed at five different laboratories for acquiring data in real time. The data will be sent to a web server and the cloud-based system will process, analyse using Neuro-Fuzzy classifier and display on a website in real time. The system will monitor the laboratories air pollutants and thermal comfort by predict the pollutant concentration and dispersion in the area i.e. Air Pollution Index (API). In case of air hazard safety (e.g., gas spills detection and pollution monitoring), the system will alert the security by activate an alarm and through e-mail. The website will display the API of the area in real-time. Results show that the system performance is good and can be used to monitor the air pollutant in the university laboratories.

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Optimum Binder Content of Asphaltic Concrete (ACW14) Mixture Incorporating Limestone

2023-01-01 , Syakirah Afiza Mohammed , Abdul Ghapar Ahmad , Ragunathan Al Santiagoo , Vikneswaran Vijean , Wan Amiza Amneera Wan Ahmad , Razi Ahmad , Kai L.S.

Due to the high demand for natural aggregates in pavement construction, researchers have been looking for alternative materials to replace natural aggregate. In this research, the optimum binder content of asphalt mixture incorporate limestones was investigated. The optimum binder content of asphalt mixture was tested according to Marshall method. About 20 % of limestone was used as aggregate replacement in asphaltic concrete mixture. To determine the stability, volumetric properties, and bitumen binder content, three percentage of asphalt binder content, namely 4.0%, 5.0% and 6.0% was prepared. From analysis, it indicated that stability and volumetric properties of asphalt mixture incorporate limestone meet the requirement set by JKR. From the result obtained, the optimum binder content of the control sample is 5.0% and optimum binder content of limestone mixture is 5.2%. The slightly different in optimum binder content value indicate that the optimum binder content of limestone mixture was comparable with control mixture.

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Investigation on effect of gas concentration in distinguishing conventional plastic and bioplastic for plastic recycling

2022-12 , Ragunathan Al Santiagoo , Allan Melvin Andrew , Wan Amiza Amneera Wan Ahmad , Razi Ahmad , Syakirah Afiza Mohammed , Abdul Ghapar Ahmad , Vikneswaran Vijean , Mustaffa Zainal

Distinguishing type of plastic was important for the recycling process. In this project, the effect on gas concentration released from composite was studied to distinguish between conventional plastic and bioplastic. This project involved the fabrication of a composite from polypropylene (PP), empty fruit bunches (EFB), and recycle acrylonitrile butadiene rubber (NBRr), with PP used as a conventional plastic and PP/NBRr/EFB used as a bioplastic. Trans-polyctylene (TOR) was used as a compatibilizer to evaluate the effect on the PP/NBRr/EFB. Tensile testing and SEM were conducted to study the mechanical properties and morphological properties on the PP/NBRr/EFB and the PP/NBRr/EFB/TOR composite. The gas sensor (MQ135) was used in this study to detect the presence of NH3 and CO2 released from heating conventional plastic and bioplastic. From the overall result, composite with TOR as compatibilizer has shown better performance than composite without TOR in mechanical, morphological and gas sensor testing. By using MATLAB software, it shows that from gas sensor testing, it can be verified to distinguish between conventional plastic and bioplastics for plastic recycling. The average classification obtained from the Probabilistic Neural Network (PNN) was 99.29 % accurate.

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Carbon footprint hotspots of prefabricated sandwich panels for hostel construction in Perlis

2017-10-16 , Norashikin Razali , Afizah Ayob , Muhammad Erwan Shah Chandra , Mohd Faiz Mohammad Zaki , Abdul Ghapar Ahmad

Sustainable design and construction have gained increasing research interest, and reduction of carbon from building construction has become the main focus of environmental strategies in Malaysia. This study uses life cycle assessment and life cycle inventory analysis frameworks to estimate the amount of carbon footprint expressed in carbon dioxide equivalent tons (CO2e) produced by manufacturing prefabricated Industrialized Building System sandwich panels and its installation for a five-story hostel in Perlis, Malaysia. Results show that the carbon footprint hotspots were centered on boiler machine operation and cement with 4.52 and 369.04 tons CO2e, respectively. This finding is due to the extensive energy used for steam heating and high engine rating for the boiler. However, for cement, the carbon footprint hotspots are caused by the large quantity of cement applied in shotcrete mixture and its high extraction and production CO2 emission values. The overall onsite materials generated 96.36% of the total carbon footprint. These carbon footprint hotspot results constitute a necessary base for the Malaysian government in accomplishing an adequate dimensioning of carbon emissions in the building sector.

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Assessment on Water Footprint of Paddy Cultivation in Kedah

2023-01-01 , Azhar N. , Wan Amiza Amneera Wan Ahmad , Syakirah Afiza Mohammed , Abdul Ghapar Ahmad , Ragunathan Al Santiagoo , Vikneswaran Vijean , Razi Ahmad

A measurable metric to gauge both the amount of water pollution and water consumption per unit of crop is the water footprint (WF). WF can be used as a thorough indicator of the utilization of freshwater resources. To increase the yield of crops, agriculture, consumed large amount of water. To prevent water shortages, it is crucial to understand how much water is consumed during agriculture. This study's goal is to estimate the region of Kedah's water footprint for paddy cultivation in the year 2017. By using CROPWAT 8.0 computer programming, climatic parameters were used for the estimation of water evapotranspiration for blue and green to proceed with the water footprint accounting. The methodological framework followed the crop water requirement (CWR) option based on the water footprint assessment manual. Focusing on the water footprint accounting phase, the blue, green and grey water footprint was calculated. The findings demonstrated that the three forms of water footprints differ significantly from one another. In Kedah, the value of the green water footprint (1201m3/ton) is higher than that of the blue water (130m3/ton) and the grey water (357m3/ton) footprints. 71% of green water footprint indicates that there is enough rainfall to support paddy growth.

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