Mok Shue Yee, Magaret Sivapragasam, Maisara Shahrom Raja Shahrom
Chitosan is formed from chitin deacetylation, but its insolubility remains challenging for industrial applications. An alternative would be employing Ionic Liquids (ILs) as a potential green solvent to dissolve chitosan. Hence, this research aims to study the optimum conditions of chitosan-[BMIM]Cl dissolution using Response Surface Methodology (RSM) and evaluate the ecotoxicity of chitosan-[BMIM]Cl mixture against Gram-positive and Gram-negative bacteria. Chitosan was obtained from heterogenous N-deacetylation of chitin using 50% sodium hydroxide solution at 100°C for 2.5 h. Chitosan dissolution in [BMIM]Cl was optimised using Central Composite Design (CCD) via RSM based on three independent factors: temperature, initial chitosan loading and dissolution time. Ecotoxicity of chitosan-[BMIM]Cl was evaluated using broth microdilution test against Escherichia coli and Staphylococcus aureus. Chitosan with a degree of deacetylation (DD) of 83.42% was obtained after three successive alkali treatments. Fourier Transform Infrared Spectroscopy (FTIR) revealed the presence of free hydroxyl groups, additional amino groups, and reduced C=O and C-H stretch intensity, indicating successful chitin deacetylation. The regression model for chitosan dissolution in [BMIM]Cl was significant (p < 0.05) with a non-significant lack of fit (p > 0.05). The optimised conditions to dissolve chitosan in [BMIM]Cl was 130°C, 1 wt. % and 72 h with a mean relative error of 1.78% and RMSE of 5.0496 wt. %. The toxicity of 10 wt. % chitosan-[BMIM]Cl mixture was “relatively harmless” (EC50 > 1000 mg/L) with an EC50 value of 3.1 wt. % for Escherichia coli and 3.2 wt. % for Staphylococcus aureus.
{"title":"Chitosan Dissolution in [BMIM]Cl Ionic Liquid: An Optimisation and Bacterial Ecotoxicity Study","authors":"Mok Shue Yee, Magaret Sivapragasam, Maisara Shahrom Raja Shahrom","doi":"10.47836/pjst.31.6.21","DOIUrl":"https://doi.org/10.47836/pjst.31.6.21","url":null,"abstract":"Chitosan is formed from chitin deacetylation, but its insolubility remains challenging for industrial applications. An alternative would be employing Ionic Liquids (ILs) as a potential green solvent to dissolve chitosan. Hence, this research aims to study the optimum conditions of chitosan-[BMIM]Cl dissolution using Response Surface Methodology (RSM) and evaluate the ecotoxicity of chitosan-[BMIM]Cl mixture against Gram-positive and Gram-negative bacteria. Chitosan was obtained from heterogenous N-deacetylation of chitin using 50% sodium hydroxide solution at 100°C for 2.5 h. Chitosan dissolution in [BMIM]Cl was optimised using Central Composite Design (CCD) via RSM based on three independent factors: temperature, initial chitosan loading and dissolution time. Ecotoxicity of chitosan-[BMIM]Cl was evaluated using broth microdilution test against Escherichia coli and Staphylococcus aureus. Chitosan with a degree of deacetylation (DD) of 83.42% was obtained after three successive alkali treatments. Fourier Transform Infrared Spectroscopy (FTIR) revealed the presence of free hydroxyl groups, additional amino groups, and reduced C=O and C-H stretch intensity, indicating successful chitin deacetylation. The regression model for chitosan dissolution in [BMIM]Cl was significant (p < 0.05) with a non-significant lack of fit (p > 0.05). The optimised conditions to dissolve chitosan in [BMIM]Cl was 130°C, 1 wt. % and 72 h with a mean relative error of 1.78% and RMSE of 5.0496 wt. %. The toxicity of 10 wt. % chitosan-[BMIM]Cl mixture was “relatively harmless” (EC50 > 1000 mg/L) with an EC50 value of 3.1 wt. % for Escherichia coli and 3.2 wt. % for Staphylococcus aureus.","PeriodicalId":46234,"journal":{"name":"Pertanika Journal of Science and Technology","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135043933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The fault detection problem is investigated for discrete-time linear uncertain systems. Instead of designing a fault detection system from the viewpoint of observer design for robust residual generation, an adaptive threshold approach is proposed to attain robustness against disturbance and norm-bounded model uncertainty. The main goal of the research is to develop a threshold design method that could establish an appropriate trade-off between false alarms and missed fault detection in the presence of model uncertainty. For this purpose, the H∞ optimization technique is adopted in the linear matrix inequality framework to compute the unknown parameters of an adaptive threshold. It is shown that the proposed fault detection system based on an adaptive threshold depends only on the system parameters and the control input of the monitored system. It is independent of robust residual generator designs in traditional observer-based fault detection systems. The effectiveness of the proposed approach is verified on two well-known benchmark systems: a direct-current motor and three tank systems. Several types of faults are successfully detected in both applications.
{"title":"Adaptive Threshold-based Fault Detection for Systems Exposed to Model Uncertainty and Deterministic Disturbance","authors":"Masood Ahmad, Rosmiwati Mohd-Mokhtar","doi":"10.47836/pjst.31.6.26","DOIUrl":"https://doi.org/10.47836/pjst.31.6.26","url":null,"abstract":"The fault detection problem is investigated for discrete-time linear uncertain systems. Instead of designing a fault detection system from the viewpoint of observer design for robust residual generation, an adaptive threshold approach is proposed to attain robustness against disturbance and norm-bounded model uncertainty. The main goal of the research is to develop a threshold design method that could establish an appropriate trade-off between false alarms and missed fault detection in the presence of model uncertainty. For this purpose, the H∞ optimization technique is adopted in the linear matrix inequality framework to compute the unknown parameters of an adaptive threshold. It is shown that the proposed fault detection system based on an adaptive threshold depends only on the system parameters and the control input of the monitored system. It is independent of robust residual generator designs in traditional observer-based fault detection systems. The effectiveness of the proposed approach is verified on two well-known benchmark systems: a direct-current motor and three tank systems. Several types of faults are successfully detected in both applications.","PeriodicalId":46234,"journal":{"name":"Pertanika Journal of Science and Technology","volume":"77 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135043934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kimberly Wei Wei Tay, Suk Fun Chin, Mohd Effendi Wasli, Zaki Musa
Synthesis parameters are of utmost importance for controlling the particle sizes of cellulose beads. This study aims to investigate the effects of synthesis parameters e.g., stirring speed (250–1250 rpm), surfactant concentrations (0.5–6.0% w/v), cellulose concentrations (1–5% w/v), and reaction temperature (30-100°C) on the particle sizes for micron-sized cellulose beads (µCBs) as well as other parameters e.g. the volume (1.0 mL) and concentration (0.1–1.0% w/v) of cellulose for nanosized (nCBs) cellulose beads using the response surface methodology (RSM). A total of 27 runs were conducted applying RSM based on the central composite design approach with Minitab-19. Cellulose concentrations were shown to have the most significant effect on both µCBs and nCBs. Under optimized conditions, the minimum and maximum mean particle size of µCBs that could be achieved were 15.3 µm and 91 µm, respectively. The predicted mean particle size for nCBs was obtained at 0.01 nm as the smallest and 200 nm as the biggest particle size under the optimum conditions. This study envisages that RSM and experiments for targeted applications such as biomedicine and agriculture could optimize the particle sizes of cellulose beads.
{"title":"Response Surface Methodology: A Versatile Tool for the Optimization of Particle Sizes of Cellulose Beads","authors":"Kimberly Wei Wei Tay, Suk Fun Chin, Mohd Effendi Wasli, Zaki Musa","doi":"10.47836/pjst.31.6.10","DOIUrl":"https://doi.org/10.47836/pjst.31.6.10","url":null,"abstract":"Synthesis parameters are of utmost importance for controlling the particle sizes of cellulose beads. This study aims to investigate the effects of synthesis parameters e.g., stirring speed (250–1250 rpm), surfactant concentrations (0.5–6.0% w/v), cellulose concentrations (1–5% w/v), and reaction temperature (30-100°C) on the particle sizes for micron-sized cellulose beads (µCBs) as well as other parameters e.g. the volume (1.0 mL) and concentration (0.1–1.0% w/v) of cellulose for nanosized (nCBs) cellulose beads using the response surface methodology (RSM). A total of 27 runs were conducted applying RSM based on the central composite design approach with Minitab-19. Cellulose concentrations were shown to have the most significant effect on both µCBs and nCBs. Under optimized conditions, the minimum and maximum mean particle size of µCBs that could be achieved were 15.3 µm and 91 µm, respectively. The predicted mean particle size for nCBs was obtained at 0.01 nm as the smallest and 200 nm as the biggest particle size under the optimum conditions. This study envisages that RSM and experiments for targeted applications such as biomedicine and agriculture could optimize the particle sizes of cellulose beads.","PeriodicalId":46234,"journal":{"name":"Pertanika Journal of Science and Technology","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135689358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jian Wen Lin, Mohd Shahrimie Mohd Asaari, Haidi Ibrahim, Mohamad Khairi Ishak, Abdul Sattar Din
Understanding the response of plant traits towards different growing conditions is crucial to maximizing crop yield and mitigating the effect of the food crisis. At present, many imaging techniques are being explored and utilized within plant science to solve problems in agriculture. One of the most advanced imaging methods is hyperspectral imaging (HSI), as it carries the spectral and spatial information of a subject. However, in most plant studies that utilized HSI, the focus was given to performing an analysis of spectral information. Even though a satisfactory performance was achieved, there is potential for better performance if spatial information is given more consideration. This review paper (1) discusses the potential of the proximal HSI analysis methods for plant traits studies, (2) presents an overview of the acceptance of hyperspectral imaging technology for plant research, (3) presents the basic workflow of hyperspectral imaging in proximal settings concerning the image acquisition settings, image pre-processing, spectral normalization, and spectral analysis, (4) discusses the analysis methods that utilize spatial information, and (5) addresses some technical challenges related to implementing hyperspectral imaging in proximal settings for plant traits analysis.
{"title":"A Review on Analysis Method of Proximal Hyperspectral Imaging for Studying Plant Traits","authors":"Jian Wen Lin, Mohd Shahrimie Mohd Asaari, Haidi Ibrahim, Mohamad Khairi Ishak, Abdul Sattar Din","doi":"10.47836/pjst.31.6.11","DOIUrl":"https://doi.org/10.47836/pjst.31.6.11","url":null,"abstract":"Understanding the response of plant traits towards different growing conditions is crucial to maximizing crop yield and mitigating the effect of the food crisis. At present, many imaging techniques are being explored and utilized within plant science to solve problems in agriculture. One of the most advanced imaging methods is hyperspectral imaging (HSI), as it carries the spectral and spatial information of a subject. However, in most plant studies that utilized HSI, the focus was given to performing an analysis of spectral information. Even though a satisfactory performance was achieved, there is potential for better performance if spatial information is given more consideration. This review paper (1) discusses the potential of the proximal HSI analysis methods for plant traits studies, (2) presents an overview of the acceptance of hyperspectral imaging technology for plant research, (3) presents the basic workflow of hyperspectral imaging in proximal settings concerning the image acquisition settings, image pre-processing, spectral normalization, and spectral analysis, (4) discusses the analysis methods that utilize spatial information, and (5) addresses some technical challenges related to implementing hyperspectral imaging in proximal settings for plant traits analysis.","PeriodicalId":46234,"journal":{"name":"Pertanika Journal of Science and Technology","volume":"164 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135689361","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Isah Aliyu, Mohd Sapuan Salit, Edi Syams Zainudin, Mohd Zuhri Mohamed Yusoff, Ridwan Yahaya
Heat treatment is a commonly known treatment subjected to aluminum alloy and their composites to improve their mechanical properties for automotive, aerospace, and marine applications. The heat treatment was carried out to determine the influence of aging time and temperature on the mechanical properties of LM26 Al alloy reinforced with 0, 2, 4, 6, 8, and 10 wt% sugar palm fiber ash (SPFA) and its precipitation kinetics. The LM26 Al/SPFA composites were fabricated through the stir casting technique, solutionized at 500oC for 2 h, and quenched in water at room temperature. The quenched composites were aged at various ageing times and temperatures and allowed to air cool. The hardness, impact energy, tensile, and compression strengths of the aged composites were appraised. In addition, the precipitation kinetics were studied to validate the precipitation temperatures of LM26 Al matrix composites. The hardness of the composites increased with aging time and temperature, with LM26 Al/10 wt% SPFA composite reaching a hardness peak of 102.10 VH at an aging temperature of 180oC after 5 h, compared to 56.70 VH for LM26 Al alloy. Similarly, after 5 h of aging at 180oC, the LM26 Al/8 wt% SPFA composite achieved maximum tensile and compression strengths of 198.21 MPa and 326.22 MPa, respectively. Precipitation temperature decreased from 584.8oC (LM26 Al alloy) to 480.46oC (LM26/ 10wt% SPFA), indicating that adding SPFA improved precipitation kinetics. The age-hardened composite with high hardness, tensile strength, and compression strength makes it a promising piston material application in the automotive industry.
{"title":"Influence of Heat Treatment on the Mechanical Properties and Precipitation Kinetic of Sugar Palm Fiber Ash Reinforced LM26 Al Matrix Composites","authors":"Isah Aliyu, Mohd Sapuan Salit, Edi Syams Zainudin, Mohd Zuhri Mohamed Yusoff, Ridwan Yahaya","doi":"10.47836/pjst.31.6.12","DOIUrl":"https://doi.org/10.47836/pjst.31.6.12","url":null,"abstract":"Heat treatment is a commonly known treatment subjected to aluminum alloy and their composites to improve their mechanical properties for automotive, aerospace, and marine applications. The heat treatment was carried out to determine the influence of aging time and temperature on the mechanical properties of LM26 Al alloy reinforced with 0, 2, 4, 6, 8, and 10 wt% sugar palm fiber ash (SPFA) and its precipitation kinetics. The LM26 Al/SPFA composites were fabricated through the stir casting technique, solutionized at 500oC for 2 h, and quenched in water at room temperature. The quenched composites were aged at various ageing times and temperatures and allowed to air cool. The hardness, impact energy, tensile, and compression strengths of the aged composites were appraised. In addition, the precipitation kinetics were studied to validate the precipitation temperatures of LM26 Al matrix composites. The hardness of the composites increased with aging time and temperature, with LM26 Al/10 wt% SPFA composite reaching a hardness peak of 102.10 VH at an aging temperature of 180oC after 5 h, compared to 56.70 VH for LM26 Al alloy. Similarly, after 5 h of aging at 180oC, the LM26 Al/8 wt% SPFA composite achieved maximum tensile and compression strengths of 198.21 MPa and 326.22 MPa, respectively. Precipitation temperature decreased from 584.8oC (LM26 Al alloy) to 480.46oC (LM26/ 10wt% SPFA), indicating that adding SPFA improved precipitation kinetics. The age-hardened composite with high hardness, tensile strength, and compression strength makes it a promising piston material application in the automotive industry.","PeriodicalId":46234,"journal":{"name":"Pertanika Journal of Science and Technology","volume":"115 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135689352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This research measured vulnerability assessment tools’ performance on a university web application, including Burp Suite and OWASP ZAP. There are three measurement criteria: (1) the number of vulnerabilities classified under risk and confidence metrics, (2) the number of vulnerability types and URL alerts classified under risk and confidence metrics, and (3) the number of vulnerabilities classified in the 2021 OWASP Top 10 vulnerabilities. Results showed that Burp Suite detected more vulnerabilities and alerts than OWASP ZAP, with a higher proportion of high-risk vulnerabilities. However, OWASP ZAP had a higher proportion of medium-confidence vulnerabilities. The comparison also revealed that the vulnerabilities identified by both tools were ranked differently within the OWASP Top 10, and there were variations in risk prioritisation between the tools. Despite these differences, the vulnerability assessment results obtained from these tools are still helpful for the university’s security analysts and administration, as mitigating cyber threats to the web application is paramount.
{"title":"Measuring Vulnerability Assessment Tools’ Performance on the University Web Application","authors":"Pita Jarupunphol, Suppachochai Seatun, Wipawan Buathong","doi":"10.47836/pjst.31.6.19","DOIUrl":"https://doi.org/10.47836/pjst.31.6.19","url":null,"abstract":"This research measured vulnerability assessment tools’ performance on a university web application, including Burp Suite and OWASP ZAP. There are three measurement criteria: (1) the number of vulnerabilities classified under risk and confidence metrics, (2) the number of vulnerability types and URL alerts classified under risk and confidence metrics, and (3) the number of vulnerabilities classified in the 2021 OWASP Top 10 vulnerabilities. Results showed that Burp Suite detected more vulnerabilities and alerts than OWASP ZAP, with a higher proportion of high-risk vulnerabilities. However, OWASP ZAP had a higher proportion of medium-confidence vulnerabilities. The comparison also revealed that the vulnerabilities identified by both tools were ranked differently within the OWASP Top 10, and there were variations in risk prioritisation between the tools. Despite these differences, the vulnerability assessment results obtained from these tools are still helpful for the university’s security analysts and administration, as mitigating cyber threats to the web application is paramount.","PeriodicalId":46234,"journal":{"name":"Pertanika Journal of Science and Technology","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135689356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Muhammad Muzamil Mustam, Norhafiz Azis, Jasronita Jasni, Rasmina Halis, Mohd Aizam Talib, Robiah Yunus, Nurliyana Abdul Raof, Zaini Yaakub
This study presents the short-term ageing study on refined, bleached and deodorised palm oil (RBDPO) and mineral oil (MO) in the presence of insulation paper, moisture, low molecular weight acid (LMA) and oxygen. The ageing experiment was performed for 7 days at 140°C. The oil was maintained dried while the paper’s moisture was varied between 0.5% and 3.5%. In total, 0.2 g of LMA and 20 mbar of oxygen pressure were initially introduced in the oil before the ageing started. Several analyses were conducted after the ageing experiment, which include the AC breakdown voltage (BDV) oil/paper, tensile strength, degree of polymerization (DP) and thermogravimetric analysis and differential scanning calorimetry (TGA-DSC). After being subjected to ageing in the presence of LMA and oxygen, the reduction of AC BDV of RBDPO is lower than MO at all moisture levels. At the same condition, the AC BDV of RBDPO-impregnated paper also maintains higher than MO-impregnated paper. The RBDPO-impregnated paper, in the presence of LMA and oxygen, has higher resistance toward ageing than MO-impregnated paper based on DP and tensile index, even in high moisture. All RBDPO are more resistant to ageing than MO in the presence of LMA and oxygen based on the high onset temperatures of the TGA-DSC analysis.
本研究介绍了在绝缘纸、水分、低分子量酸(LMA)和氧气存在下，精炼、漂白和脱臭棕榈油(RBDPO)和矿物油(MO)的短期老化研究。在140℃下进行7 d的老化实验。当纸张的水分在0.5%到3.5%之间变化时，油保持干燥。在老化开始之前，首先向油中注入0.2 g LMA和20 mbar的氧气压力。老化实验结束后进行了交流击穿电压(BDV)、油/纸抗拉强度、聚合度(DP)、热重分析和差示扫描量热分析(TGA-DSC)等分析。在LMA和氧气存在下老化后，RBDPO在所有水分水平下的AC BDV还原率都低于MO。在相同条件下，rbdpo浸渍纸的AC BDV也保持高于mo浸渍纸。rbdpo -浸渍纸在LMA和氧的存在下，即使在高水分条件下，也比基于DP和拉伸指数的mo -浸渍纸具有更高的抗老化性能。在LMA和氧气存在的情况下，所有RBDPO都比MO更耐老化。
{"title":"Short-term Ageing Study on the Palm Oil and Mineral Oil in the Presence of Insulation Paper, Moisture, Low Molecular Weight Acid, and Oxygen","authors":"Muhammad Muzamil Mustam, Norhafiz Azis, Jasronita Jasni, Rasmina Halis, Mohd Aizam Talib, Robiah Yunus, Nurliyana Abdul Raof, Zaini Yaakub","doi":"10.47836/pjst.31.6.16","DOIUrl":"https://doi.org/10.47836/pjst.31.6.16","url":null,"abstract":"This study presents the short-term ageing study on refined, bleached and deodorised palm oil (RBDPO) and mineral oil (MO) in the presence of insulation paper, moisture, low molecular weight acid (LMA) and oxygen. The ageing experiment was performed for 7 days at 140°C. The oil was maintained dried while the paper’s moisture was varied between 0.5% and 3.5%. In total, 0.2 g of LMA and 20 mbar of oxygen pressure were initially introduced in the oil before the ageing started. Several analyses were conducted after the ageing experiment, which include the AC breakdown voltage (BDV) oil/paper, tensile strength, degree of polymerization (DP) and thermogravimetric analysis and differential scanning calorimetry (TGA-DSC). After being subjected to ageing in the presence of LMA and oxygen, the reduction of AC BDV of RBDPO is lower than MO at all moisture levels. At the same condition, the AC BDV of RBDPO-impregnated paper also maintains higher than MO-impregnated paper. The RBDPO-impregnated paper, in the presence of LMA and oxygen, has higher resistance toward ageing than MO-impregnated paper based on DP and tensile index, even in high moisture. All RBDPO are more resistant to ageing than MO in the presence of LMA and oxygen based on the high onset temperatures of the TGA-DSC analysis.","PeriodicalId":46234,"journal":{"name":"Pertanika Journal of Science and Technology","volume":"2013 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135689359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Muhammad Hakirin Roslan, Norhafiz Azis, Mohd Zainal Abidin Ab Kadir, Jasronita Jasni, Mohd Fairouz Mohd Yousof
This paper examines the influence of cavity size and location in the insulation paper on the Partial Discharge (PD) activities through Finite Element Method (FEM). The model consisted of a conductor wrapped with insulation paper. Two different locations of the spherical cavities were introduced in this study, namely Location 1 (L1) and Location 2 (L2), located at the center and left corner of the insulation paper. The model introduced two different sizes of cavities with diameters of 0.5 mm and 0.8 mm. An AC voltage source of 17 kV, 50 Hz, was applied at the conductor while the bottom of the insulation paper was grounded. The real and apparent PDs were obtained by integrating the current flowing through the cavity and ground electrode with the respective surface area. The simulation was carried out for 100 cycles. The resultant model was used to study the PD occurrence, magnitude, and Phase Resolved Partial Discharge (PRPD) within the insulation paper. It is found that the large cavity size produces a lower number of PD occurrences per cycle than the small cavity size. The large cavity size produces a higher charge magnitude as compared with the small cavity size. The PD occurrence per cycle and charge magnitude are higher for the cavity location at L1 compared to L2. The PRPD yields the same pattern for cavity location at L1 and L2, whereby the differences are only on the charge magnitude and PD occurrence per cycle.
{"title":"The Influence of Cavity Size and Location Within Insulation Paper on the Partial Discharge Activities","authors":"Muhammad Hakirin Roslan, Norhafiz Azis, Mohd Zainal Abidin Ab Kadir, Jasronita Jasni, Mohd Fairouz Mohd Yousof","doi":"10.47836/pjst.31.6.15","DOIUrl":"https://doi.org/10.47836/pjst.31.6.15","url":null,"abstract":"This paper examines the influence of cavity size and location in the insulation paper on the Partial Discharge (PD) activities through Finite Element Method (FEM). The model consisted of a conductor wrapped with insulation paper. Two different locations of the spherical cavities were introduced in this study, namely Location 1 (L1) and Location 2 (L2), located at the center and left corner of the insulation paper. The model introduced two different sizes of cavities with diameters of 0.5 mm and 0.8 mm. An AC voltage source of 17 kV, 50 Hz, was applied at the conductor while the bottom of the insulation paper was grounded. The real and apparent PDs were obtained by integrating the current flowing through the cavity and ground electrode with the respective surface area. The simulation was carried out for 100 cycles. The resultant model was used to study the PD occurrence, magnitude, and Phase Resolved Partial Discharge (PRPD) within the insulation paper. It is found that the large cavity size produces a lower number of PD occurrences per cycle than the small cavity size. The large cavity size produces a higher charge magnitude as compared with the small cavity size. The PD occurrence per cycle and charge magnitude are higher for the cavity location at L1 compared to L2. The PRPD yields the same pattern for cavity location at L1 and L2, whereby the differences are only on the charge magnitude and PD occurrence per cycle.","PeriodicalId":46234,"journal":{"name":"Pertanika Journal of Science and Technology","volume":"100 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135689360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Muhammad Izzuddin Rosli, Sharifah Abdullah, Nur Asmaliza Mohd Noor
The use of rainwater is widely recognized as a dependable solution to reduce and mitigate the effects of water scarcity. Research on rainwater harvesting systems has increased significantly in recent years, especially on methods and treatment systems. A rainwater harvesting system can be described as collecting and storing rainwater that can be used rather than waste as runoff. A rainwater collection system might lessen the reliance on the public water supply. This study aims to determine the suitability of a rainwater harvesting system at a double-story house, thus identifying the suitable tank size for installation. This study’s analysis used the Tangki NAHRIM 2.0 with localized input data such as rainfall, suitable roof area, and roof runoff coefficient. Findings from this study indicate that installing the rainwater harvesting system at a double-story house is suitable, and the optimum tank size is 3m3 by considering all the activities that contribute to water usage. Concisely, installing a rainwater harvesting system can reduce the monthly water bill and minimize the usage of treated water, thus preventing water scarcity in the future.
{"title":"Utilizing Rainwater Harvesting System for Water Scarcity at a Double-Story Residential House","authors":"Muhammad Izzuddin Rosli, Sharifah Abdullah, Nur Asmaliza Mohd Noor","doi":"10.47836/pjst.31.6.18","DOIUrl":"https://doi.org/10.47836/pjst.31.6.18","url":null,"abstract":"The use of rainwater is widely recognized as a dependable solution to reduce and mitigate the effects of water scarcity. Research on rainwater harvesting systems has increased significantly in recent years, especially on methods and treatment systems. A rainwater harvesting system can be described as collecting and storing rainwater that can be used rather than waste as runoff. A rainwater collection system might lessen the reliance on the public water supply. This study aims to determine the suitability of a rainwater harvesting system at a double-story house, thus identifying the suitable tank size for installation. This study’s analysis used the Tangki NAHRIM 2.0 with localized input data such as rainfall, suitable roof area, and roof runoff coefficient. Findings from this study indicate that installing the rainwater harvesting system at a double-story house is suitable, and the optimum tank size is 3m3 by considering all the activities that contribute to water usage. Concisely, installing a rainwater harvesting system can reduce the monthly water bill and minimize the usage of treated water, thus preventing water scarcity in the future.","PeriodicalId":46234,"journal":{"name":"Pertanika Journal of Science and Technology","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135689353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chidiebere Okeke, Othman Mohammad Lutfi, Hizam Hashim, Mohd Zainal Abdin Ab Kadir, Noor Izzri Abdul Wahab, Osaji Emmanuel, Samuel Nwagbara, Collins Chimeleze
The annual increase of the global load demand has led to higher penetration of inverter-based renewable energy resources like wind farms and solar PV into the modern grid system. Distance relay may mal-operate by incorrectly estimating line impedance as fault during swing scenarios considering the infeed contributions impact from renewable sources. The negative impact of these integrated power electronics-based devices on the power swing blocking (PSB) and out-of-steps tripping (OST) functions of the distance relay characteristics has not been extensively discussed in previous studies. This study divulges a comprehensive review of the various PSB and OST schemes studies conducted to prevent relay mal-operation during power swing (PS) and symmetrical faults. Also, the large-scale renewable resources penetrations impact the PS characteristic and trip decision operation of the distance relay divulged. The mining of distance relay event records for hidden useful knowledge deployment for intelligent PSB and OST functions is the future research direction. Using the distance relay divulged knowledge will assist in reducing the failure rate level of PSB and OST function distance relaying schemes, hence improving the degree of reliability/dependability of the power system under different operating conditions.
{"title":"Renewable Energy Impact on Distance Relay Power Swing Blocking and Fault Discrimination: A Review","authors":"Chidiebere Okeke, Othman Mohammad Lutfi, Hizam Hashim, Mohd Zainal Abdin Ab Kadir, Noor Izzri Abdul Wahab, Osaji Emmanuel, Samuel Nwagbara, Collins Chimeleze","doi":"10.47836/pjst.31.6.14","DOIUrl":"https://doi.org/10.47836/pjst.31.6.14","url":null,"abstract":"The annual increase of the global load demand has led to higher penetration of inverter-based renewable energy resources like wind farms and solar PV into the modern grid system. Distance relay may mal-operate by incorrectly estimating line impedance as fault during swing scenarios considering the infeed contributions impact from renewable sources. The negative impact of these integrated power electronics-based devices on the power swing blocking (PSB) and out-of-steps tripping (OST) functions of the distance relay characteristics has not been extensively discussed in previous studies. This study divulges a comprehensive review of the various PSB and OST schemes studies conducted to prevent relay mal-operation during power swing (PS) and symmetrical faults. Also, the large-scale renewable resources penetrations impact the PS characteristic and trip decision operation of the distance relay divulged. The mining of distance relay event records for hidden useful knowledge deployment for intelligent PSB and OST functions is the future research direction. Using the distance relay divulged knowledge will assist in reducing the failure rate level of PSB and OST function distance relaying schemes, hence improving the degree of reliability/dependability of the power system under different operating conditions.","PeriodicalId":46234,"journal":{"name":"Pertanika Journal of Science and Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135689355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：