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Integration of a spreadsheet software in first year introduction to engineering and seminar course to develop students’ digital skills
No full textThe Introduction to Engineering (ITE) and Industrial Seminar and Profession (ISP) courses conducted at the School of Chemical and Energy Engineering, Universiti Teknologi Malaysia, are integrated courses, which implement the Cooperative Problem-based Learning (CPBL) methods in the same semester. Based on these integrated courses, the main aim of this paper is to present results of a study that investigate the qualitative impact of spreadsheet hands-on seminar on the first-year students' digital skill. At the beginning of the semester, students given sustainability-based project to work on, which requires them to collect and to report the data in a series of presentations and written reports. In order to present those data, they need to use analysis tools such as a spreadsheet software. The students were introduced with some in-depth applications of the Microsoft Excel software through the seminar sessions in the ISP course. With the knowledge gained, they are expected to implement it in the CPBL project. Throughout the semester, the students are required to prepare reflection journals every 3 weeks to analyze, reflect and evaluate their learning process. In order to evaluate the students' development of their digital skills, instructors will analyze the journals to identify common attributes that they have managed to gain. This analysis may also help the instructors to further improved the activities for the coming semester to further enhance the student digital skills
A novel hybrid extreme learning machine-whale optimization algorithm for bearing fault diagnosis
No full textIn order to avoid fatalities and ensure safe operation, a good and accurate diagnosis method is required. A diagnosis method based on extreme learning machine (ELM) has attracted much attention and the ELM method had been applied in various field of study. The advantages of the ELM method which are rapid learning rate, better generalization performance and ease of implementation makes the ELM method suitable to be used in various field including fault diagnosis fields. However, the performance of the ELM method becomes inefficient due to incorrect selection of neurons number and randomness of input weight and hidden layer bias. Hence, this paper aims to propose a novel hybrid fault diagnosis method based on ELM and whale optimization algorithm (WOA), known as ELM-WOA for bearing fault diagnosis. Four different types of bearing datasets from Case Western Reserve University Bearing Data Centre were used in this paper in order to present the performance of the proposed method. Based on the result, the performance of the proposed method was able to surpass the performance of the conventional ELM
Design and implementation of hybrid medium DP-DQPSK DWDM ROF transmission system for different weather conditions
Get PDFThis document Designing system with Free-space optical (FSO) communication can supply high-speed digital data linkages to rural regions where geography, setup costs, and groundwork safety are major obstacles. Transmission impairments and space loss could be considered major challenges for handling the FSO system. This work, it has been designed and analyzed a system based on the combination of Dual Polarization Differential Quadrature Phase Shift Keying (DP-DQPSK) and Dense Wavelength Division Multiplexing (DWDM) using the Direct Detection (DD) technique. The proposed system has been utilized with a hybrid transmission medium of Single-Mode Fiber (SMF) with a fixed length of 60 km and FSO with a varied length of (5, 7, and 9) km. The system was designed with Optisystem software 18 and consist of 64 channels and 14 Gbps of data rate per channel to make the system 5G communication compatible, 3.5 GHz RF electrical signals have been used to modulate the optical carrier. The channels 1, 6, 12, …, 64 were selected as samples among all channels to be investigated and analyzed along with four different atmospheric weather conditions. Additionally, the proposed system is designed to investigate based on different weather attenuation that affected the parameters of Quality Factor (QF) and Bit Error Rate (BER). The significant advantage of the proposed system by using the DD technique is no reference wave is required. Hence, make the system less complex and possible to be implemented and tested via different weather conditions. Results obtained indicate reverse relation between the QF and both the FSO distance and attenuation. While BER-based parameters showed a direct relation. For light air and haze, the results showed that the system has higher reliability for all the three investigated FSO distances. For the medium haze, the system has shown the capability to transfer as far as 7 km. And for the rain condition, the system capability was set to 5 km
Development of cost-effective energy management strategy for stand-alone hybrid system
Get PDFDeployment of Photovoltaic (PV) and Wind Turbine (WT) as a stand-alone system are the most affordable solution to the electrification problem in the rural areas. However, the main challenge that hinder the sustainability of PV and WT is the output fluctuation. Thus, the battery and the non-Renewable Energy (RE) sources are required to make sure the continuous supply to the load is met. Therefore, the purpose of this paper is to propose the rule-based Energy Management Strategy (EMS) for the stand-alone hybrid system in order to ensure the continuity of supply and the minimum utilization of non-RE can be achieved. The continuous monitoring is designed to avoid the degradation of battery performance while minimizing the non-RE cost. The efficient Stage of Charge (SoC) limit of battery is investigated and applied in this study to store the excess RES power effectively. In this paper, the diesel fired Microturbine (MT) is selected as a non-RE source to integrate into the stand-alone hybrid system that consists of PV, WT and battery. The result shows that the proposed rule-based EMS for the in the stand-alone hybrid system is able to reduce the cost of MT operation to a minimum. Restricting the SoC limits effects the use of MT
Assessing the suitability of affordable housing based on demand criteria
Get PDFAffordable housing has become essential to provide housing with affordable prices, but most of the locations of affordable housing are often not suitable with the people's demand. To assess the suitability of affordable housing, several initiatives has been developed, to match the demand and location of the affordable housing, but most the models lacks of spatial element, other model focusing on the goal related to site suitability to cities, and people's preferences of housing. This study aims to integrating spatial information and analysis to assessing the suitability level of affordable housing in Malaysia. This assessment model consists of 3 main indicators; suitability house according to neighbourhood context, demographic factor and commute distance. The method use in this study is using multi-Criteria Analysis, using weighted scoring techniques. The results show that most of the affordable housing score more than 60% average, with the highest score are 84% and the lowest score are 57.9%. this shows that the suitability level of affordable housing in the study area is good. These indicators can be used for further investigation of other affordable housing, and also in finding the suitable site for affordable housing in the future
Interferometric synthetic aperture radar coherence constraints in heavily vegetated tropics
Get PDFSuccess of Interferometry Synthetic Aperture Radar (InSAR) technique for deriving digital elevation model (DEM) in the heavily vegetated humid tropic using Sentinel-1 SAR has been controversial, owing to the difficulty in achieving good coherence. Yet achievable coherence with Sentinel-1 SAR over the heavily vegetated humid tropic has rarely been reported. Consequently, this paper evaluates coherence achievable with Sentinel-1 SAR over the heavily vegetated humid tropic. Twelve Sentinel-1 SAR over part of Johor selected based on perpendicular and temporal baselines considerations, were used as pairs of six reference and secondary images respectively and processed using Sentinel Application Platform (SNAP) to derive coherence maps and analysed accordingly. The result shows that regardless of image pairs baseline characteristics, coherence of above 0.6 over the heavily vegetated humid tropic with Sentinel-1 SAR can only be achieved in barely 10% of the study area. This result shall serve as eye-opener to geoscience community, especially SAR enthusiast looking forward to leveraging on SAR clouds penetrating ability, and Sentinel-1 SAR open access and short revisit circle to apply Sentinel-1 SAR in deriving DEM over heavily vegetated humid tropical environment. However, future studies shall focus on assessing consistency of good coherence patches and their usability in acquiring elevation
Stay-at-home: impact of pandemic covid-19 on the use of indoor space in Malaysian households
Get PDFThe prolongation of the Pandemic COVID-19 has undermined the healthcare system and negatively impacted the economy and social development on a global and regional scale. At the human settlement level, responding to the pandemic situation has altered the broad spectrum of our daily routine down to the family and individual levels. Prior to the lockdown popularly known as the Movement Control Order (MCO), which the government introduced, the public was urged to limit outdoor movements and stay at home hence, encouraging the adoption of Work From Home (WFH) for employees and Home-based Teaching and Learning (PdPR) for the academic community and school students. Other than technological readiness for online working and teaching, the new normal also prompted new challenges for households in utilizing indoor spaces at home, especially for quarantine as well as for WFH and PdPR activities. In this light, a series of household surveys using questionnaires to determine the preference and usage of indoor space among households have been conducted in 39 locations/settlements across peninsular Malaysia. A total of 504 respondents participated and fieldwork and interview processes. Findings of the study indicated a majority of respondents have to designate indoor spaces/rooms for home quarantine (58%), and the three indoor spaces, in particular, have been monitored regularly by respondents during the pandemic, namely living areas (39%), kitchen (25%) and bedroom (21%). During MCO, most of them spent 1 to 4 hours per day for PdPR (43%), and 47% of respondents have a designated learning space at home for PdPR. In summary, pandemic COVID-19 has raised awareness among households regarding the selection and usage of indoor space to conduct various activities while they have to stay at home
Analysis of deterministic models for dengue disease transmission dynamics with vaccination perspective in Johor, Malaysia
Get PDFDengue is a mosquito-borne disease which has continued to be a public health issue in Malaysia. This paper investigates the impact of singular use of vaccination and its combined effort with treatment and adulticide controls on the population dynamics of dengue in Johor, Malaysia. In a first step, a compartmental model capturing vaccination compartment with mass random vaccination distribution process is appropriately formulated. The model with or without imperfect vaccination exhibits backward bifurcation phenomenon. Using the available data and facts from the 2012 dengue outbreak in Johor, basic reproduction number for the outbreak is estimated. Sensitivity analysis is performed to investigate how the model parameters influence dengue disease transmission and spread in a population. In a second step, a new deterministic model incorporating vaccination as a control parameter of distinct constant rates with the efforts of treatment and adulticide controls is developed. Numerical simulations are carried out to evaluate the impact of the three control measures by implementing several control strategies. It is observed that the transmission of dengue can be curtailed using any of the control strategies analysed in this work. Efficiency analysis further reveals that a strategy that combines vaccination, treatment and adulticide controls is most efficient for dengue prevention and control in Johor, Malaysia
From student’s experience: does e-learning course structure influenced by learner’s prior experience, background knowledge, autonomy, and dialogue
Get PDFBackground: E-learning is increasingly becoming a preference in higher education institutions worldwide; this is intended to assist educational institutions in achieving objectives to meet the proportion of individuals with their educational opportunities. Nevertheless, instructors and students frequently have concerns with their capacity to succeed in E-learning environments. Objectives: This study aimed to presents common e-Learning challenges in regard to e-learning courses structure and its relations to various factors, for instance; students’ autonomy, prior knowledge and experience, students-students dialogue, and students-instructor dialogue, and proposes solutions to these challenges based on the transactional distance theory. Moreover, this study presents evidence from Malaysian higher institutions based on theoretical models for e-learning course structure and its relations to the factors mentioned above. Methods: Data have been collected from 680 university learners all over Malaysia. Data were then examined using exploratory factor analysis, confirmatory factor analysis, and structural equation modelling employing Smart PLS 3.0 software. Results and conclusion: Research findings indicated that e-learning course structure was affected by all dimensions of overall path analysis findings: student autonomy, students background, student-instructor dialogue, and student-student dialogue. However, the e-learning course structure showed insignificant with students’ prior experience. Implications: Implications for universities are discussed accordingly. Such findings provide vital support to the integrative association among collaborative control (CC) and transactional distance theory (TDT) regarding e-learning environments experience, which might support universities administrators in the higher education industry to implement, plan and evaluate online learning platforms applications in their institutions
Terrain mapping for the southwestern desert of Iraq using interferometry method from sentinel-1A images
Get PDFSynthetic aperture radar Interferometry is a popular three-dimensional imaging technique for creating a Digital Elevation Model. Using traditional methods for creating DEMs and terrain mapping is one of the methods that require high cost and time-consuming, which has affected the creation and updating of terrain maps in Iraq, so this study aims to use the InSAR technology to generate DEM, which contributes to the creation of terrain maps. In this work, the synthetic aperture radar interferometry approach was used on the interference stack generated from a pair of Sentinel-1A images within the SNAP program to generate a DEM and a terrain map of the desert region in south-western Iraq. The elevations of the digital elevation model were compared with those of the RTK-GCPs points in the region of interest. The results obtained from this study are a terrain map with the contour lines generated from the digital elevation model created by the InSAR technique with an accuracy of 18 m, with the root mean square error of the DEM being 8.17. The outputs prove the effectiveness of InSAR technology in generating accurate DEM that contributes to creating terrain maps in less time and cost than traditional methods