Universiti Teknikal Malaysia Melaka: UTeM Open Journal System
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IDENTIFICATION OF SECOND PHASE DEPOSITED ON La-DOPED SrTiO3 PEROVSKITES SYNTHESIZED BY CITRIC-GEL METHOD
No full textWe examined deposition process of the second phase during sintering Sr0.7La0.3TiO3 perovskite at 1400°C and analyzed the detailed composition by means of SEM-EDX technique. The second phase deposited at the corners of the Sr0.7La0.3TiO3 matrix grains was confirmed to be Sr-doped rare-earth B-type La2O3
Spectral and Nonlinear Properties of the Sum of Boolean Functions
Get PDFBoolean functions are the mathematical basis of modern cryptographic algorithms. However, in practice, a set of interrelated Boolean functions is often used to construct a cryptographic algorithm. This circumstance makes the task of research of cryptographic quality, in particular, the distance of the nonlinearity of the sum of few Boolean functions important. The nonlinearity distance of a Boolean function is determined by the maximum value of its Walsh-Hadamard transform coefficients. In this paper, we proposed a formula that is the equivalent of the summation of Boolean functions in the Walsh-Hadamard transform domain. The application of this formula, as well as the Walsh-Hadamard spectral classification made it possible to determine the structure of WalshHadamard transform coefficients, and the distance of the nonlinearity when summing the Boolean functions lengths N 8 and N 16 , indicating valuable practical application for information protection
ROTARY ULTRASONIC ASSISTED MACHINING OF MOULD AND DIE MATERIAL
No full textThe high strength properties of hardened steel AISI D2 material (~51 HRc) have created problems to the conventional machining process; poor machined surface, high cutting force, extreme machining temperature and rapid tool wear. In order to solve the discrepancies in machining the material, this paper proposed a hybrid machining process technique that combined a high frequency ultrasonic vibration (~20 kHz) with the rotating end mill. An in-house ultrasonic tool holder that fitted the CNC machine spindle was developed to perform the ultrasonic assisted machining process. A set of experimental work was conducted to evaluate the improvement of the ultrasonic vibration in the cutting process. The evaluation included the effects of machining parameter namely cutting speed, feed rate, depth of cut, ultrasonic frequency and vibration amplitude in improving the surface roughness value for machining hardened AISI D2 material. The analytical results demonstrated that the presence of the ultrasonic vibration was able to improve the machined surface roughness in that up to 80% reduction in Ra value was observed as compared to the conventional machining process within the same cutting conditions
INFORMATION COMMUNICATION AND TECHNOLOGY UNDERGRADUATES’ PERCEPTIONS ON E-PORTFOLIO AS A TOOL IN A TECHNICAL COMMUNICATION COURSE
Get PDFThe demands for soft skills have arisen tremendously over recent years as universities incorporate these skills into their curriculum. Graduates need the technical knowledge as well as the soft skills in order to perform effectively in the workplace. This paper investigates the impact of an e-Portfolio in a technical communication course to enhance the information technology students’ soft skills in communication, critical thinking and problem solving and teamwork. The objective of the research is to find out the undergraduates’ perceptions on e-Portfolio as a tool in a technical communication course. An open-ended questionnaire was distributed to 65 students to elicit information at the end of the semester. The findings showed that most of the students’ found that e-Portfolio had helped them to improve their learning. This indicates that e-Portfolio has the potential as a tool to enhance students’ soft skills in their learning
Medium Term Load Forecasting Using Statistical Feature Self Organizing Maps (SOM)
No full textLoad forecasting is an essential tool for power system activity and planning. With the increase in development and the expansion of power system, it is important for the electrical utility to make a decision in ensuring that there would be enough supply of electricity to deal with the increasing demand. This research presents the Medium Term Load Forecasting using the artificial neural networks: Kohonen’s Self-organizing Maps. The main purpose of this paper was to understand the ability of Self-Organizing Maps in forecasting the load demand and to train and test via SelfOrganizing Maps method using the selected features. Using data provided by the Global Energy Forecasting Competition (GEFCom2012), this paper focused on the missing data from the year 2005 and 2006 for the load forecasting. The loaded data were trained, tested, and forecasted using SOM Toolbox in MATLAB software. The accuracy of the forecasted data was determined by calculating the error of each forecasted data by comparing them with the actual data. Then, the Mean Absolute Percentage Error was computed to determine the accuracy of the results
Enhanced Performance of Narrowband Power Line Communications using Recursive Least Squares Filter
Get PDFNoises presented in a power line communication channel tend to distort the message signals, leading towards the reception of erroneous data at the receiver end. Mitigation of noise existent in power line has always been of prime interest and helped to improve the BER performance of a communication system as it accounts for efficient data transmission. In this work, adaptive filters based on the Recursive Least Squares (RLS) algorithm and Least Mean Square (LMS) algorithms have been implemented in Simulink to investigate the effectiveness of an Adaptive Noise Canceller for the mitigation of Gaussian and Impulsive Noises present in a narrowband power line channel model. The performance of the RLS algorithm against that of the LMS algorithm was compared in adaptive filtering for the same channel conditions. The error performances of BPSK and FSK schemes for the channel model in a generic digital communication system were also compared in Simulink. Furthermore, the use of convolutional codes and interleaving for the correction of random bit errors and for condensing the negative effect of burst errors respectively were investigated during the transmission of data signals over the generic communication system designed in Simulink. From the findings of the study, it has been concluded that the RLS algorithm proves to be more effective than the LMS algorithm. For a BER of 10-5, a coding gain of less than 10 dB is achievable for both Binary Phase Shift Keying and Binary Frequency Shift Keying. With the addition of convolutional coding and convolutional interleaving, the error performance of the channel is further improved, rendering the power line channel more reliable for data communication
ROBOTICS COMPETITION-BASED LEARNING FOR 21ST CENTURY STEM EDUCATION
Get PDFThis article proposes the Robotics Competition-based Learning (R-CBL) in the 21st century learning environment to integrate Science, Technology, Engineering, and Mathematics (STEM) education. This study has an attempt to highlight the connections between the STEM disciplines as well as the integration of 21st-century competencies to spark students’ interest towards the STEM. The problem statement revealed in this article is Malaysia may soon experience a serious human capital deficiency in the STEM field. Thus, it is important to practice a new pedagogy for 21st century integrated STEM education. The objectives of this study is to investigate the effectiveness of R-CBL to increase students’ interest towards STEM in “Robot Olympics Malaysia 2018”. The finding in this research shows the educational robotics as the digital tool can promote STEM learning among secondary school students. In conclusion, by practising Robotics Competition-based Learning in 21st century STEM classroom, learners are expected to have attentiveness in the integrated STEM curriculum. The implication of this pedagogy is to bridge the gap between the expected curriculums, written curriculum, and taught the curriculum. Keywords: robotics, competition, STEM education, 21st centur
Experimental Investigation on Thermoelectric Generator for Battery- Charger Based Oven
Get PDFIn this research paper, thermoelectric generator (TEG) module was embedded inside the oven to harvest electrical energy from heat waste of the kitchen oven. The development of experimental setup was investigated in closed-circuit from room temperature rise to 150°C in 60 min using kitchen oven with custom-made aluminum heatsink with built-in water-cooling tank attached on the TEG module. The maximum voltage output was generated about 1.87V in single TEG module where gradient of TEG was measured about 0.0337V/°C. The harvested output of voltage was demonstrated by charging a single lithium battery ‘AA’ in 110 mins for full-charged and it was able to power a LED torch light
ELECTROENCEPHALOGRAM (EEG) STUDIES ON HUMAN PERCEPTION IN COLOURS
No full textThis manuscript presents an investigation of human perception on colors using the Electroencephalogram (EEG) device. Studies of the human perception using EEG is expanding in various discipline that links electronics to many fields of study interest. The aim of this study is to observe the human perception and its level of calmness in the brain. Observation was made on the alpha band that was generated from various kinds of colors to different human. This study further focused on the EEG frequency of Alpha brainwaves and its relation to the brain lobes. In this experiment, the low-cost Emotive Epoch EEG neuroheadset device with 16 channels of electrodes were used. Subjects were instructed to look into different colors displays during the experiment. The EEG data was analyzed using the Fourier transform of Power Spectral Density (PSD). The results were observed from all the lobes but focusing were made on the occipital lobe and the averages of the alpha waves Power Spectral Density in two channels of the occipital were obtained. The analysis result from this study showed that the alpha wave produced from different participants are affected through different colors. This observation further depicted that human are calm through their color of interest