Journals of Universiti Tun Hussein Onn Malaysia (UTHM)
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Development of a Tiltrotor Propulsion System for Hybrid VTOL Fixed-Wing Drones
Get PDFHybrid Unmanned Aerial Vehicles (UAVs) integrate features from both fixed-wing and multirotor UAVs. The fixed wings efficiently distribute aerodynamic loads while combining aerodynamic properties with the multirotor configuration. A tiltrotor mechanism is necessary to facilitate the transition between hover and forward flight modes. This research focuses on developing a comprehensive tiltrotor propulsion system for a fixed-wing aircraft. Two methodologies were employed: software simulation and experimental testing. A restricted flight test was conducted using a test rig to observe the drone\u27s behaviour at various throttle levels, revealing that each motor produced 2.12 kg of thrust, resulting in a total thrust of 6.12 kg. The drone successfully lifts off at its maximum take-off weight of 3.1 kg. Five potential materials for the components supporting the front and rear motors were tested through simulations, with Polymaker\u27s PolyTerra PLA, a modified polylactic acid material, proving to be the best option. It demonstrated maximum equivalent von Mises stress values of 4.0122 MPa for the front motor supports and 2.8205 MPa for the rear motor supports, along with minimal deformations of less than 0.01 mm. Therefore, the results demonstrate that Polymaker\u27s PolyTerra PLA is an optimal material for the support components of the front and rear rotors, ensuring structural reliability and suitability for hybrid vertical take-off and landing (VTOL) fixed-wing drones, as evidenced by its exceptional performance under simulated and experimental conditions
Aerodynamic Analysis of S809 Airfoil: A Stall Validation with RANS k-ω Turbulence Models
Get PDFThis study examines the aerodynamic efficacy of the S809 airfoil at six angles of attack: −14.23°, −5.15°, 0°, 5.13°, 9.22°, and 10.21°. It uses steady two-dimensional RANS with two closures: k–ω SST (Menter) and k–ω Standard. It also checks the results against wind-tunnel data from NREL. We digitized experimental pressure distributions with calibrated axes, which meant that there was a vertical error of ±0.03 in Cp was used, and the uncertainty in the integrated lift is about 10⁻³. Without re-processing, the reported experimental uncertainties from NREL were kept. The study links coefficient trends to the measured surface-pressure fields so that you don\u27t have to use integrals to see if they agree. Both models have a pre-stall range of 5.13° to 9.22°, and the curves and wake thickness match the measurements. The slope of the lift curve is also very close to what was found. There are differences between the start of the stall and the end of the load. The k–ω SST model gets the order of the stalls right, but it makes them less intense. This means that the lift is a little too high and the pressure drag is a little too low at 9.22° and 10.21°. The k–ω Standard model keeps separation from happening longer and gives the biggest lift overprediction and the lowest drag in the same range. When the incidence is negative, both models predict fewer losses than the tunnel data. The solutions show a small positive lift and drag matches well at about 0°. This means that the problem is with the residual circulation offset and not the friction model. The results show that design and control can work well between 5.13° and 9.22°. They also show where you need to calibrate or control the transition as the separation gets closer. A subsequent study will employ URANS to broaden the scope into the post-stall regime to rectify unsteady phenomena
Kemahiran Menyelesaikan Masalah dan Kemahiran Membuat Keputusan dalam Kalangan Pelajar Kolej Vokasional Gerik: Problem-Solving Skills and Decision-Making Skills Among Gerik Vocational College Students
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Kemahiran menyelesaikan masalah ialah merangkumi proses pengumpulan maklumat yang relevan, menggunakan penaakulan logik, mengenal pasti penyelesaian yang mungkin, menilai hasil yang berpotensi bagi setiap penyelesaian, dan membuat keputusan yang berkesan. Kemahiran membuat keputusan melibatkan proses memilih tindakan atau keputusan daripada beberapa alternatif yang ada, dengan mengambil kira maklumat yang berkaitan, matlamat yang dikehendaki, dan keadaan semasa. Tujuan kajian ini adalah untuk mengukur tahap kemahiran menyelesaikan masalah dan kemahiran membuat keputusan dalam kalangan pelajar Kolej Vokasional Gerik serta melihat perbezaan signifikan antara pelajar lelaki dan perempuan terhadap kemahiran menyelesaikan masalah dan kemahiran membuat keputusan dalam kalangan pelajar SVM 1 dan 2. Kajian ini menggunakan reka bentuk tinjauan dengan pendekatan kuantitatif dan seramai 195 responden yang telah memberi maklum balas melalui borang soal selidik. Analisis deskriptif digunakan untuk mengukur tahap kemahiran menyelesaikan masalah dan tahap kemahiran membuat keputusan dalam kalngan pelajar. Dapatan kajian menunjukkan bahawa skor min bagi kedua-dua tahap kemahiran berada pada tahap yang tinggi iaitu kemahiran menyelesaikan masalah M=4.22 dan kemahiran membuat keputusan M=4.29. Manakala analisis inferensi, iaitu Ujian T tidak bersandar, digunakan bagi mengukur perbezaan signifikan antara pelajar lelaki dan perempuan terhadap kemahiran menyelesaikan masalah dan kemahiran membuat keputusan dalam kalangan pelajar Kolej Vokasional Gerik. Dapatan kajian menunjukkan P=0.01, yang bermaksud terdapat perbezaan signifikan antara pelajar lelaki dan perempuan terhadap kemahiran menyelesaikan masalah dan kemahiran membuat keputusan dalam kalangan pelajar Kolej Vokasional Gerik. Secara keseluruhannya, hasil kajian menunjukkan bahawa pelajar SVM 1 dan 2 di Kolej Vokasional Gerik mahir dalam kemahiran menyelesaikan masalah dan kemahiran membuat keputusan tidak kira dalam pembelajaran mahupun kehidupan harian mereka.
English:
Problem solving skills include the process of gathering relevant information, using logical reasoning, identifying possible solutions, evaluating the potential outcomes of each solution, and making effective decisions. Decision-making skills involve the process of choosing an action or decision from several available alternatives, considering relevant information, desired goals, and current circumstances. The purpose of this study is to measure the level of problem-solving skills and decision-making skills among Gerik Vocational College students and to see significant differences between male and female students regarding problem-solving skills and decision-making skills among SVM 1 and 2 students. This study uses a design survey with a quantitative approach and a total of 195 respondents who have given feedback through a questionnaire. Descriptive analysis is used to measure the level of problem-solving skills and the level of decision-making skills among students. The findings of the study show that the mean score for both skill levels is at a high level, namely problem-solving skills M=4.22 and decision-making skills M=4.29. While inferential analysis, which is an independent T-test, was used to measure the significant difference between male and female students in terms of problem-solving skills and decision-making skills among Gerik Vocational College students. The results of the study show P=0.01, which means there is a significant difference between male and female students regarding problem solving skills and decision-making skills among Gerik Vocational College students. Overall, the results of the study show that SVM 1 and 2 students at Gerik Vocational College are proficient in problem-solving skills and decision-making skills, whether in learning or in their daily lives
Kesedaran Ibu Bapa Luar Bandar Terhadap Kepentingan Kelas Tambahan Berbayar bagi Subjek Kritikal: Satu Kajian Awal: Rural Parents\u27 Awareness Of The Importance Of Paid Supplementary Classes For Critical Subjects: A Preliminary Study
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Kajian ini dijalankan bagi menilai tahap kesedaran ibubapa luar bandar terhadap kepentingan menghantar anak-anak mereka ke kelas tambahan berbayar, di samping mengenal pasti faktor-faktor yang mempengaruhi keputusan tersebut serta halangan yang dihadapi dalam mengekses perkhidmatan pendidikan tambahan. Kajian ini juga menganalisis kesan potensi kelas tambahan terhadap pencapaian pelajar luar bandar dalam subjek-subjek teras seperti Matematik, Sains dan Bahasa Inggeris. Menggunakan kaedah tinjauan secara kuantitatif melibatkan 132 orang responden, dapatan menunjukkan bahawa tahap kesedaran adalah tinggi, dengan 96.2% responden menyatakan mereka menyedari kewujudan kelas tambahan berbayar dikawasan masing-masing.Selain itu, 77.3% telah menghantar anak ke kelas tambahan, dengan majoriti mengganggap kelas tersebut sangat penting untuk peningkatan prestasi akademik. Matematik dikenal pasti sebagai subjek yang paling diberi keutamaan, manakala halangn utama yang dikenalpasti merangkumi kekangan kewangan, akses lokasi dan kekurangan guru berkelayakan.Hasil kajian menunjukkan bahawa walaupun kesedaran adalah tinggi, halangan struktur dan sosio-ekonomi masih menjadi penghalang utama kepada akses yang saksama terhadap pendidikan tambahan dikawasan luar bandar. Implikasi kajian mencadangkan keperluan intervensi dasar dan sokongan bersasar bagi menigkatkan peluang pendidikan pelajar luar bandar.
English:
This study was conducted to assess the level of awareness among rural parents regarding the importance of sending their children to paid supplementary classes, as well as to identify the factors influencing such decisions and the barriers faced in accessing additional educational services. The study also analyzes the potential impact of supplementary classes on the academic achievement of rural students in core subjects such as Mathematics, Science, and English. Using a quantitative survey method involving 132 respondents, the findings show a high level of awareness, with 96.2% of respondents stating they are aware of the existence of paid supplementary classes in their respective areas. Additionally, 77.3% had sent their children to supplementary classes, with the majority considering these classes very important for improving academic performance. Mathematics was identified as the highest priority subject, while the main barriers identified include financial constraints, location accessibility, and a shortage of qualified teachers. The study results indicate that despite high awareness, structural and socio-economic barriers remain the main obstacles to equitable access to supplementary education in rural areas. The implications of the study suggest the need for policy interventions and targeted support to enhance educational opportunities for rural students
Power Grid Synchronous Detection Based on Voltage and Frequency
Get PDFThe power grid system is a complex electrical network that supply electricity from power generation to consumers. Required the variation of voltage and frequency are maintained within the normative limits. The aim of this research is to design a circuit model that simulate a power grid synchronous system using Proteus 8.17 software. This research had designed and built a model that can detect grid condition based on voltage and frequency variation. Arduino UNO microcontroller had been used in this research to control the overall operation flow. The functionality of the model had been examined through software simulation testing. Six different conditions had been set to test the functionality of the model. The assigned conditions include Normal Voltage (between 207V and 253V), Under Voltage (<207V), Over Voltage (>253V), Normal Frequency (between 49.5Hz and 50.5Hz), Under Frequency (<49.5Hz) and Over Frequency (>50.5Hz). Overall, the developed model in simulation using Proteus 8.17 software had a accuracy when detecting grid based on over/under voltage and over/under frequency variation
Assessment of a Safe Work-Impulse for Farmers: A Case Study of Ilara-Mokin, Ondo State, Nigeria
Get PDFThe study measured the heart rates of farmers in Ilara-mokin while they carried out a few regular farm tasks with a view to create a safe work-impulse chart for farmers in that locality. This is expected to provide the information required for the adequate use of muscular force and the prevention of fatigue or physical exertion, during farming. Farmers who were available and were willing to participate in the study were divided into five age groups, such as below 25, 25-34, 35-44, 45-54, and above 54 years, and their heart rates were monitored and recorded under three different categories of farm activities or load (light load, medium load, and heavy load) using a premium pressure monitor with comfit cuff. The time and the heart rate at which the farmers feel a sense of discomfort or tiredness were used to evaluate the safe work-impulse for each category of activities. The result shows that farmers below 45 years of age record a work-impulse of about 9.0M kNs and 7.2H kNs for medium and heavy loads respectively while older farmers manage to sustain medium and heavy loads at a work-impulse of 7.2M kNs, 5.4M kNs and 9.0M kNs, 5.4M kNs respectively. In conclusion, the study revealed that while farmers of any age can handle a light activity for a longer period of time than 18 minutes, they may not be able to sustain heavier loads for a longer period
Comparative Study of Commercial and Plastic Waste Resins for Groundwater Treatment
Get PDFGroundwater contamination by organic and inorganic pollutants poses serious health and environmental concerns. Conventional resins are effective but costly. There is a need for low-cost, eco-friendly alternatives, particularly through plastic waste valorization. This study compares the performance of commercial and plastic waste resins for groundwater treatment. Scanning electron microscopy analysis revealed that the commercial resin had a smooth, porous structure, while the plastic waste resin showed a rough, irregular surface. Energy dispersive X-ray and Fourier transform infrared spectroscopy analysis confirmed key ion exchange functional groups, including sulfonic acid, in the commercial resin. X-ray diffraction analysis showed the commercial resin was amorphous with low crystallinity. Results showed that the commercial resin outperformed the plastic waste resin by removing 98.6% biochemical oxygen demand (BOD), 85% chemical oxygen demand (COD), 88.9% total suspended solids (TSS), 50% total dissolved solids (TDS), and 66% iron. The plastic waste resin achieved lower removal rates of 66.7% TSS, 25% TDS, and 19.2% COD. In column method, the commercial resin removed 91.65% total hardness within 4 hours at 2163 cm³ dosage, while the plastic waste resin achieved up to 52.12%. The superior performance is linked to the commercial resin’s favorable structure and functional groups for ion exchange. The use of plastic waste resin as a potential ion exchange material for water treatment supports waste valorization and aligns with circular economy principles. However, its performance requires further optimization, which can be pursued through strategic collaboration with water treatment industries
Peranan Nilai Syukur Dalam Mengatasi Putus Asa: Satu Pendekatan Berasaskan Tazkiyatun Nafs: The Role of Gratitude Value in Overcoming Despair: An Approach Based on Tazkiyatun Nafs
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Kecenderungan kepada putus asa semakin membimbangkan dalam kalangan masyarakat, khususnya golongan muda yang berdepan dengan pelbagai tekanan hidup. Fenomena ini menuntut pendekatan yang lebih menyeluruh dan bersifat kerohanian dalam menangani kelemahan daya tahan jiwa. Kajian ini memberi fokus kepada peranan nilai syukur sebagai elemen penting dalam mengatasi perasaan putus asa, berdasarkan pendekatan tazkiyatun nafs dalam al-Quran. Objektif utama kajian ini adalah untuk menjelaskan konsep syukur menurut perspektif Islam, mengenal pasti hubungan antara syukur dan daya tahan jiwa, serta mencadangkan strategi pembangunan syukur dalam kehidupan individu. Kajian ini menggunakan pendekatan kualitatif melalui analisis kandungan ayat-ayat al-Quran, disokong dengan dapatan literatur berkaitan psikologi positif dan nilai kerohanian. Dapatan kajian menunjukkan bahawa syukur bukan sahaja memperkukuh hubungan manusia dengan Pencipta, bahkan mampu merubah perspektif terhadap ujian hidup dan membina ketenangan dalaman. Implikasinya, nilai syukur wajar dijadikan elemen teras dalam intervensi kerohanian dan pembangunan jati diri, khususnya dalam kalangan generasi muda yang terdedah kepada krisis makna hidup dan tekanan jiwa.
English:
The tendency toward despair has become increasingly concerning within society, particularly among the younger generation who face various life pressures. This phenomenon calls for a more holistic and spiritually grounded approach to addressing the fragility of the human psyche. This study focuses on the role of gratitude (shukr) as a crucial element in overcoming feelings of despair, based on the tazkiyatun nafs (purification of the soul) approach in the Qur’an. The main objectives of this study are to explain the concept of gratitude from an Islamic perspective, to identify the relationship between gratitude and psychological resilience, and to propose strategies for cultivating gratitude in individual life. A qualitative approach is employed through content analysis of selected Qur’anic verses, supported by a review of relevant literature on positive psychology and spiritual values. The findings reveal that gratitude not only strengthens one’s relationship with the Creator but also transforms one’s perspective on life’s trials and fosters inner tranquility. The implications suggest that gratitude should be integrated as a core element in spiritual interventions and character development programs, particularly among the younger generation who are vulnerable to existential crises and psychological distress
An Optimization Algorithm of Synthesizing a Feed-Forward Neural Network to Determine a Human Functional State Using Stabilometry Data
Get PDFBalance is crucial to an individual\u27s quality of life and functional performance. Stability measurement analysis and balance assessment rely on center-of-pressure coordinates and numerical data. Although machine learning algorithms have been applied to analyze stabilization measurements, accurately determining an individual\u27s balance stability remains a challenge despite promising results. This study assesses the efficacy of a classification model—specifically, artificial neural networks (ANNs) utilizing an evolutionary algorithm (EA)—trained on three stability indicators to evaluate human health status. The methodology involved enhancing the learning process of artificial neural networks (ANNs) by dividing the hidden layers into multiple ANNs based on the number of neurons, optimizing them using an evolutionary algorithm, and then combining them to formulate new optimal hidden layers. This method expedited the optimization process and determined optimal designs. This study illustrates that optimal learning phases enhance the selection of appropriate artificial neural network architectures for distinguishing between healthy and diseased conditions, attaining accuracy rates of 99% to 100% for the A-indicator, 98% to 100% for the AW-indicator, and 97% to 100% for the AXY-indicator. The findings demonstrate that the integration of evolutionary algorithms and artificial neural networks markedly enhances predictive accuracy in healthcare, necessitating additional research to corroborate these results
Blockchain-Based Cheat Detection System for Multiplayer Online Games
Get PDFThe presence of competitive gaming in the video game industry requires a system that could promote fairness in the gameplay aspect. Many players have utilized networking attacks such as Distributed Denial of Service (DDoS) to win a competitive game. This action will enable players to gain an unfair advantage during gameplay. Attempts to cheat using DDoS attacks in competitive gaming created a significant need for a prevention mechanism. To satisfy this, we have designed a cheat detection system by leveraging Godot DotNet capabilities to connect a game client to the Ethereum Blockchain environment via Nethereum Web3 capabilities. Blockchain is used because it can keep records in an untampered state. We tested our system on the classic Pong game by capturing the positional data of all moving gameplay elements and sending them into the blockchain network. The location coordinate of each central gameplay element in the game is stored in the blockchain. The gameplay evaluation shows that 64-bit hex data of gameplay elements’ coordinates have been transmitted and stored successfully. The performance evaluation indicates that the game runs at 180 FPS using 6% of the GPU workload and 11% of the CPU workload, resulting in a time difference of under 200 ms for each transaction