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- PublicationMicroplastics And Heavy Metals Assessments And Its Associated Health Risk In Fishes From Kerian, Pinang And Tembus River(2025-09)Rivers play an important role ecologically and commercially for local communities. However, the rapid growth of anthropogenic activities has led to ecosystem degradation through the discharge of microplastics (MPs) and heavy metals (HMs). MPs, small plastic particles classified as contaminants, are widely reported in aquatic organisms and act as vectors for toxic pollutants, leading to bioaccumulation in fish and raising concerns about food safety and toxicity. Similarly, HMs bioaccumulation in fish represents a serious threat to human health. This study aimed to assess the occurrence of MPs and HMs in fish from the Kerian, Pinang, and Tembus rivers in Penang, Malaysia, and their potential risks to human health. MPs were extracted from fish gastrointestinal tracts and identified by microscopy and Fourier transform infrared spectroscopy (FTIR), while HMs in muscle tissues were quantified using Inductively Coupled Plasma Optical Emission spectroscopy (ICP-OES).
- PublicationKesan Modul Cbt-Dbt Terhadap Kecenderungan Bunuh Diri Dalam Kalangan Remaja Gay Dan Lesbian(2025-09)Kajian ini bertujuan membina Modul CBT-DBT dan menilai keberkesanannya dalam menangani kecenderungan bunuh diri dalam kalangan remaja gay dan lesbian di Malaysia. Pembangunan modul dijalankan melalui dua fasa utama. Fasa pertama melibatkan pembinaan modul menggunakan Model Pembinaan Modul Sidek, termasuk penyediaan draf, ujian rintis dan penilaian. Fasa kedua menumpukan kepada pengujian kesan intervensi modul terhadap kecenderungan bunuh diri. Modul ini memperoleh tahap kesahan yang tinggi dengan skor 95.5% berdasarkan penilaian sembilan orang pakar.
- PublicationHubungan Kemahiran Insaniah Dan Efikasi Kendiri Terhadap Kesediaan Kerjaya Pelajar Kolej Vokasional(2025-09)Kajian ini bertujuan untuk mengenal pasti tahap kemahiran insaniah, efikasi kendiri dan kesediaan kerjaya pelajar di kolej vokasional. Kajian ini turut mengkaji hubungan antara kemahiran insaniah dan efikasi kendiri dengan kesediaan kerjaya pelajar serta mencadangkan satu kerangka model pengukuran kesediaan kerjaya pelajar di kolej vokasional. Terdapat lima elemen kemahiran insaniah, lima elemen efikasi kendiri dan empat elemen kesediaan kerjaya yang dikaji.
- PublicationThe Effects Of Killing Processes And Different Drying Methods On Nutrient Content And Physicochemical Characteristics Of Black Soldier Fly (Hermetia Illucens) Larvae(2025-09)Rising feed costs highlight black soldier fly (BSF) larvae as a sustainable feed option, with drying essential for stability. This study evaluated the effects of two killing methods (blanching (100 °C for 40 seconds) and freezing (-20 °C for 24 hours)) and three drying methods (sun drying (25-33 °C for 23-41 h), freeze-drying (-18 to - 50 °C for 72 h with oven drying at 80 °C for 24 h) and dehydrator drying (60 °C for 24h)) on the nutritional and physicochemical qualities of BSF larvae.
- PublicationGeospatial Analysis Of Domestic Energy Consumption In Kaduna State, Northwest Region Of Nigeria(2025-09)Energy is a vital element for the socio-economic development of a country. However, many households in Nigeria lack access to modern energy sources and rely on traditional fuels. This has a negative impact on household health and the environment. This study geospatially analyzed domestic energy consumption in Kaduna State. The study had five objectives, namely to identify patterns of domestic energy consumption by household, to analyze factors influencing domestic energy choices, to analyze spatial distribution patterns and rates of domestic energy consumption, to assess the environmental implications of domestic energy consumption, and to predict future patterns of domestic energy consumption in the study area.
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- ItemPengurusan Krisis Dan Proses Membuat Pertimbangan (Sensemaking) Oleh Pengamal Perhubungan Awam Di Malaysia: Kajian Kes Krisis Halal Cadbury(Universiti Sains Malaysia, 2017-10)Objektif utama kajian ini adalah untuk memahami dan menerangkan proses sensemaking oleh pengamal perhubungan awam semasa krisis organisasi yang dicetuskan oleh media sosial termasuk tiga objektif khusus; (1) untuk mengenal pasti peranan pengamal perhubungan awam semasa krisis organisasi yang dicetuskan oleh media sosial (2) untuk memahami cara pengamal perhubungan awam memberi makna terhadap media sosial semasa krisis organisasi dan (3) untuk mengenal pasti kepentingan sensemaking dalam mempengaruhi Kitaran Perlakuan Komunikasi (Communication-behavior-cycle) semasa pengamal perhubungan awam mengendalikan krisis organisasi. Kajian ini mengaplikasikan kaedah kualitatif dengan reka bentuk kajian kes.
- PublicationOptimization Of Optical And Radar Satellite Data In Google Earth Engine For Monitoring Oil Palm Changes In Tropical River Basins(2023-09)Accurate mapping of oil palm plantations is crucial for planning agricultural best management practices. Google Earth Engine (GEE), a cloud-based computing platform, allowing users to process multi-source satellite images more quickly and effectively. In fact, it is difficult to distinguish oil palm from other crops using only optical satellites due to the issue of cloud cover in tropical regions. Unfortunately, there is only little scientific understanding about how various satellite images within GEE can be helpful for mapping oil palm plantations. Hence, this study aims to determine the optimal combination of open-source optical and radar satellite data for mapping oil palm plantations in tropical river basins using the Muda River Basin (MRB) and the Johor River Basin (JRB) as test sites. First, the two machine learning classifiers available in GEE, random forest (RF) and support vector machine (SVM), were compared to identify which is the most effective classifier for mapping oil palm plantations. Then, eight different data combinations have been constructed from the satellite images and indices such as C-band Sentinel-1, L-band PALSAR2, Landsat8, Sentinel-2, topographic, Normalized Difference Vegetation Index (NDVI), Normalized Difference Water Index (NDWI), etc. Lastly, the optimal data combination was employed to project future oil palm distribution using the CA-Markov approach. The findings demonstrate that RF outperformed SVM in mapping oil palm plantations in both river basins.
- ItemAnalysis of harmonics current minimization on power distribution system using voltage phase shifting concept(2007)Non linear loads such as switch mode power supply and adjustable speed drive in three phase three wires power distribution system can causes line current system distorted. The non linear loads on three phases three wires power distribution system were produced dominantly 5-th and 7-th order harmonic currents. Increasing of harmonics current on electric power distribution system leads to degradation of system performance. To reducing the harmonics current on power distribution system should be minimized the 5-th and 7-th order harmonics current components. The minimization process of harmonic current is accomplished by voltage phase angle shifting on the two branches of non-linear load system, where the different phase angle between both of branches should be300 . Because of 5-th order harmonic current component is negative sequence and 7-th order harmonic current component is positive sequence, therefore these harmonic current components on the line system are opposite each other. Base on this concept, the phase shifter designing to harmonic minimization is “Double Symmetric Zig-zag Autotransformer”. The experimentation results for harmonic current minimization in three phase three wires power distribution system using this voltage phase angle shifting concept. It shows that the total current harmonic distortion on the line current system can be reduced from 30.03 % become 10.2 %. This value is fulfill the IEEE standard 519-1992 recommended, where the IEEE standard 519-1992 allows the maximum limits for total current harmonic distortion containing in power distribution system is bellow than 20 %. The advantage of this concept is simply and practice, because it is only required electromagnetic circuit and does not require sensor and control and the electronic components. Beside this, The Double Symmetric Zig-zag Autotransformer harmonic reducer has low rating kVA, smaller size, low losses and higher efficiency.
- ItemSimulations For Steam Methane Reforming Over Ni/Al2O3 Catalyst In A Fixed Bed Reactor And A Membrane Reactor(Universiti Sains Malaysia, 2021-07-01)The limitations of steam methane reforming (SMR) process in fixed bed reactor (FBR) is thermodynamic equilibrium constraint and the requirement of high operating temperature. Membrane reactor (MR) have huge application potential for the equilibrium limited, endothermic SMR process due to the simultaneous withdrawal of reaction product, H2. The steady-state behavior of SMR process in FBR and MR are examined by developing a 1-D, pseudo-homogeneous mathematical modelling framework that operates at isothermal and isobaric mode. The calculation procedures was performed using MATLAB and both of the reactor models were validated against experimental data. Comparative SMR performance assessment in terms of methane conversion (XCH4, H2 yield and selectivity of CO (SCO) and CO2 (SCO2) between FBR and MR were accordingly conducted. The increasing temperature has positive impact on XCH4 and H2 yield, but at temperature above 650 ℃, the positive impact of H2 removal in MR becomes less significant compared to FBR. Besides, SCO2 and SCO are only affected by temperature in which increasing temperature promotes the reverse water gas shift reaction, resulting in the increase of SCO. For FBR, SCO exceeds SCO2 at around 590 ℃ while for MR, SCO exceeds SCO2 at around 610 ℃. Next, the effect of increasing reaction pressure show an opposite trend for MR and FBR, in MR, higher XCH4 is obtained when pressure increases due to the increase of H2 partial pressure driving force but in FBR, higher pressure is not favoured. In addition, methane inlet flow rate higher than 0.03 kmol/h suppressed the positive impact of H2 removal in MR while lower permeation zone pressure (Pperm) and higher sweep gas flow rate improve the reaction performance in MR.
- PublicationArtificial neural network for gas-oil flow pattern recognition using capacitance tomography data(2009-04-01)The technique to recognize the oil and gas flow pattern in a pipe is needed in the oil and gas industry to monitoring the condition of the oil and gas pipe system. Any mistake or malfunction may lead to serious loss and endanger the workers and environments. Generally there are lots of flow pattern such as Empty, Full, Stratified, Bubble, Core and Annular. The Electrical Capacitance Tomography (ECT) technique is used to take the cross sectional data of the pipe. The Artificial Neural Networks (ANNs) is used to recognize the flow patterns. This project uses the Multilayer Perceptron (MLP) as the ANNs model. The MLP is trained, validated, and tested with the ECT data. The ECT data is divided into three groups, training, validation, and testing. The Matlab software is used to build the MLP architecture. The learning algorithms used for this project is the Levenberg-Marquardt algorithms and the Quasi-Newton algorithms. Result show that trained MLP is able to give a percentage of accuracy of 99.102% in oil and gas flow pattern recognition. This shows that the MLP is suitable to be used in the oil and gas flow pattern recognition.