Volume 31(1) 2019
Table of contents
|1.||A Review on Existing Sensors and Devices for Inspecting Railway Infrastructure
Amir Falamarzi*, Sara Moridpour & Majidreza Nazem
This paper presents a review of sensors and inspection devices employed to inspect railway defects and track geometry irregularities. Inspection of rail defects is an important task in railway infrastructure management systems, and data derived from inspections can feed railway degradation prediction models. These models are utilised for predicting potential defects and implementing preventive maintenance activities. In this paper, different sensors for detecting rail defects and track irregularities are presented, and various inspection devices which utilise these sensors are investigated. In addition, the classification of the sensors and inspection devices based on their capabilities and specifications is carried out, which has not been fully addressed in previous studies. Non-Destructive Testing (NDT) sensors, cameras and accelerometers are among sensors investigated here. Correspondingly, trolleys, Condition Monitoring Systems (CMS), hi-rail vehicles and Track Recording Vehicles (TRV) are among major inspection devices that their capabilities are studied. Furthermore, the application of new devices, including smartphones and drones, in railway inspection and their potential capabilities are discussed. The review of previous and recent approaches shows that CMSs are more cost-effective and accessible than other railway
Keywords: Railway; Non-destructive; Condition Monitoring; Sensors; Inspection
|1 – 10|
|2.||Evaluation of Rural Transportation Technology : A Case Study of Bicycle and Motorcycle Trailers
Olukayode O. Oyesiku, Olasunkanmi O. Akinyemi, Solomon O. Giwa, Nurudeen S. Lawal & Babatunde O. Adetifa*
Transportation of goods in rural communities, especially from farms, is one of the major bottlenecks experienced by rural dwellers. Bicycle and motorcycle trailers have been a major intervention proposed by several studies but, this technology has not been fully adopted and it has no detailed evaluation report. This study, therefore, evaluates the performance of different bicycle and motorcycle trailer designs. Three different designs of bicycle trailers (fixed plate design (FPD), convertible plate design (CPD) and wire mesh design (WMD)) and two designs of motorcycle trailers (FPD and CPD) were developed. Four performance evaluation tests (laden mass, forward speed, pull and haulage tests and a computer-based simulation of stress/strain analysis) were carried out. The optimum load capacity (OLC) of WMD bicycle trailer is 100 kg at a speed of 5.2– 6.3 km/hr, while that of FPD and CPD bicycle trailers are 100 kg at a speed of 3.8 – 4.2 km/hr. The OLC for the FPD and CPD motorcycle trailer was 200 kg at a speed of 6.2 – 8.4 km/hr. Static structural analysis of the trailer chassis shows that the maximum stress and strain of the trailers were 2.95 × 106 Pa and 8.22 × 10-6 mm, respectively. This study shows the suitability of the bicycle and motorcycle trailers in small-scale goods conveyance and its suitability for the rural community.
Keywords: Bicycle; Drawbar; Haulage; Laden Mass; Motorcycle; Trailers
|11 – 18|
|3.||Optimization of Angular Distortion on Weld Joints Using Taguchi Approach
Amir Arifin*, Gunawan, Agung Mataram, Irsyadi Yani, Diah Kusuma Pratiwi, Muhammad Yanis & Khoirul Anwar Sani
Welding process is joining method which is extensively utilized in shipbuilding and automotive industry. Distortion is a classic problem encountered during the welding process which always occurs in welding processes. Distortion on weld joint involves many parameters that influence such as properties of materials and welding parameters. The objective of this work is to investigate effect of various processes of Shielded Metal Arc Welding (SMAW) on angular distortion in low carbon steel weld joints. To obtain optimum parameters of angular distortion, the effect various welding parameter is analysed using Taguchi Method. In this work, the effect of groove type, welding current and root opening are investigated for determining angular distortion. Taguchi method with L9 orthogonal array is utilized to analysed contribution for each parameter. ANOVA results revealed that the welding current the significant contribution parameter, on the other hand root opening shows minimum contribution to determine angular distortion value. Optimum parameter is obtained with groove type, welding current and root opening is X, 75A and 3 mm, respectively. Welding current parameter is considered the most significant contribution to determine for angular distortion effect due to has the highest contribution (50.04 %) than the other parameters groove type and root opening, with contribution value 21.76 %, 2.38%, respectively. Moreover, hardness test result on weld joint shows that X type groove has maximum hardness number than the other groove type.
Keywords: Taguchi Method; Angular Distortion; Carbon Steel
|19 – 23|
|4.||Developing An Islamic Farayez System Applying Software Engineering
Sadia Tabassum*, A. H. M. Sajedul Hoque, Sharaban Twahura & Mohammad Osiur Rahman
Distribution of deceased person’s wealth is a divine law in Islam. This distribution should be accurate; otherwise a gruesome punishment is waiting in hereafter. The combination of relatives of late person is diverse which makes the computation of distribution difficult. In order to ease the computation of shares of slain person, a software system can be designed for Islamic Farayez which is the premier concern of this article. The existing software systems cannot compute the distribution precisely always and furthermore have lack of proper explanation of the system. Having studied ‘Islamic Shariah’ for all possible combinations of relatives of dead person, a system has been modelled and developed which provides the knowledge of Islamic inheritance and distributes the wealth of deceased accurately through which user can be galvanized to follow. Here the Islamic Farayez has been analyzed and modelled using structured approach. After fixing different scenario of Islamic Farayez of a dead person, individual cases are analysed using three levels of Data Flow Diagram (DFD). Hence, DFD illustrated the organization of the functional components of the system; and as a consequence, based on this, the graphical form of algorithm or flow-chart of the overall Islamic Farayez system is developed. Finally, mathematical models are derived for all possible combination of relatives of late person and then developed the software for Islamic Farayez system. The reliability, accuracy, integrity and robustness of the proposed Islamic Farayez system are rigorously justified by comparing the proposed system generated results with manual results as well as other existing software generated results for various complex cases. It is recommended to use this proposed Islamic Farayez system as an expert assistant for distribution of deceased person’s wealth among his/her eligible relatives.
Keywords: Islamic Farayez, Structured System Analysis and Design, Data Flow Diagram (DFD)
|25 – 38|
|5.||ERP Software Selection Model for Small and Medium-Sized in Retail Sector Using Analytic Network Process
Ilham Setya Hermawan, Euis Nina Saparina Yuliani* & Zulfa Fitri Ikatrinasari
Small and medium sized (SME) retailers strive to maintain the balance of demand and supply in their stores. By maintaining the availability of items, they able to provide positive shopping experience for customers. Therefore, they are able to survive in a competition with large retailers. The technological advances and the shopping behavior are among the factors that encourage SME retailers to adopt the technology information system for supports information between business functions to keep the balance of supply, demand and their distribution. One of the many ways to maintain balance of demand and supply is by implementing Enterprise Resource Planning (ERP) (). However, ERP is quite difficult for SME retailers to be implemented in their organization. Selecting the optimal ERP software is a critical process in the early phase of an ERP project. This study aimed to investigating the priority (preference) of the criteria and alternatives using the Analytic Network Process (ANP) approach for the small and medium-sized retailers focusing in Jakarta. This study conducted by observation and interviews with the experts who have experience with ERP and small and medium-sized retailers. In this study, the pairwise comparisons used to assess the proposed alternatives and criteria. Furthermore, this study also calculates the overall score of the criteria and alternatives for analyzing the relation and preference of the criteria and alternatives. The theory of ANP used to evaluate all criteria and alternatives with expressed numerically. The findings of this study provide an overview that small and medium-sized retail companies tend to require systems or ERP software. In this study, there are 5 criteria most preferred: ease of customization, technical aspects, functionality and compatibility with other systems, and software prices. These criteria are considered to ensure the good operational activities. The most preferred alternative is SAP Business One, as it scored highest on several criteria, Odoo and Acumatica. The limitation of this study is that this study only used three ERP software programs as alternatives and this study focuses only for the small and medium-sized retailers in Jakarta.
Keyword: Enterprise Resource Planning (ERP); Analytic Network Process (ANP); Retail; Small and Medium –Sized Enterprise
|39 – 46|
|6.||Thermomechanical Process Modelling of 40NICRMO8-4 Alloy by Artificial Neural Networks
Esmaeil Alibeiki*, Jamal Rajabi & Javad Rajabi
Artificial neural networks (ANNs) as simplified model of mankind’s neural system, are capable of simulating and predicting real world complex problems which are challenging and expensive to model physically. In this study the correlation between the flow stresses and strain rate, temperature, strain in thermomechanical process of 40NICRMO8-4 alloy has been modelled. The results revealed that flow stress for every strain value is less at high temperatures compared to those at low temperatures and material resistance against deformation will also decrease as temperature goes down. Moreover, increasing in strain rate when temperature is constant results in recrystallization to happen in higher strain values at times shorter. The employed neural network for this study was a feed forward multilayer perceptron trained with common back propagation algorithm. Similar to any other ANNs, the employed network receives some parameters as inputs and delivers some as outputs. The inputs given to this model were temperature, strain and strain rate while flow stress parameter was collected as requested output. Outputs, with high precision of approximately 99% accuracy, were predicted and produced during training phase. Likewise, the predicted output of the ANN model achieved an R-value of about 0.99871 compared with of those experimental values. Best results were obtained with an ANN model consist of two hidden layers trained with Levenberg–Marquardt training algorithm.
Keywords: Thermomechanical Process; 40NICRMO8-4 Alloy; Artificial Neural Network; Flow Stress
|47 – 56|
|7.||Tricycles for Nigerian Public Transport Unit: Assessment of Ergonomics Design Considerations
Adeyemi Hezekiah O,* & Yusuf Taofeek AAbstract
Tricycles are becoming more popular commercial means of transport across all Nigerian cities. This study evaluated ergonomics status of this development. Measurement of seven variables comprising, seats’ height, width and cushion inclination as well as space available for legs, back rest inclination, access/exit doors and circulation corridors, were carried out on the sampled Tricycle. The measured variables were compared with both the standard recommended for urban transport unit and the corresponding anthropometric data of users from Southwest and Eastern parts of Nigeria (SW/EN). Data were collected from 175 passengers through questionnaire to measure the degree of comfort/discomfort derived using the transit unit. Microsoft Office Excel 2007 was used for statistical analysis. About 59% of the total passengers reported discomfort using Tricycle. Among these, 26.6% complained of strains at hips/upper legs, 22.9% neck pains and 21.0% knees/lower legs. More than 23% of the affected attributed this to lack of space for legs’ adjustment. All seats’ dimensions deviated from the required standard. The z-test result also showed significant differences for 87.5% of the total measured in-element parameters when compared with corresponding 95th anthropometric data of users from SW/EN. The study showed that passengers using Tricycles are susceptible to injuries connected with awkward postures, vibrations and external contact stress. Improving design with the recommended standards for urban transport, as suggested by the finding, may help in overtaking these challenges.
Keywords: Tricycle; Passengers; Transportation; Discomforts; Ergonomics
|57 – 63|
|8.||Kenaf Fiber Composites: A Review on Synthetic and Biodegradable Polymer Matrix
Dulina Tholibon, Izdihar Tharazi, Abu Bakar Sulong, Norhamidi Muhamad, Nur Farhani Ismail, Mohd Khairul Fadzly Md Radzi, Nabilah Afiqah Mohd Radzuan* & David Hui
This review paper deals with the previous and current works published on the kenaf fiber composites. Kenaf is grown commercially in South East Asia country and widely used in the construction and infrastructure as well as in the automotive industry. Kenaf fiber is usually reinforced with synthetic based polymer resin such as polypropylene. However, recent studies tend to concern towards the environmental issues which kenaf fiber act as an alternative natural fiber competitor. Moreover, the combination of the natural fiber and the biodegradable polymer able to reduce the negative impact on human health. Hence, researcher-initiated the interest focusing on the biodegradable materials obtained from the renewable sources. A huge attention gave to the kenaf fiber reinforced bio-polymer materials such as polylactic acid. The processing technique and the fiber orientation within the composite materials are discussed extensively in order to obtain the maximum composite performance. Results indicated that the mechanical properties; tensile strength and tensile modulus, are improved as the kenaf fiber was aligned in uni-direction. Therefore, this paper overview on the kenaf retting types in the common form of kenaf fibers and discussing the thermoplastic polymer matrices types used in the fabrication processes. In addition, the challenging of using kenaf fibers composites and its application in the automotive industry also highlighted.
Keywords: Natural Fiber; Thermoplastic Polymer; Biodegradable Polymer; Automotive Components
|65 – 76|
|9.||Energy Models of Zigbee-Based Wireless Sensor Networks for Smart-Farm
Hilal Bello Said*, Rosdiadee Nordin & Nor Fadzilah Abdullah
In this paper, we evaluated several network routing energy models for smart farm application with consideration of several factors, such as mobility, traffic size and node size using wireless ZigBee technology. The energy models considered are generic, MICA and Zigbee compliant MICAz models. Wireless sensor networks deployment under several scenarios are considered in this paper, taken into account commercial farm specification with varying complex network deployment circumstances to further understand the energy constraint and requirement of the smart farm application. Several performance indicators, such as packet delivery ratio, throughput, jitter and the energy consumption are evaluated and analysed. The simulation result shows that both throughput and packet delivery ratio increases as the nodes density is increased, indicating that, smart farm network with higher nodes density have a superior Quality of Service (QoS) than networks with sparsely deployed nodes. It is also revealed that traffic from the mobile nodes causes increase in the energy consumption, overall network throughput, average end-to-end delay and average jitter, compared to static nodes traffic. Based on the results obtained, the Generic radio energy models consumed the highest total energy, while MICAz energy consumption model offers the least consumption, having the lowest ‘Idle’ and ‘receive’ modes consumption. The MICAz model also has the lowest total consumed energy as compared with the other energy models, suggesting that it is the most suitable energy model that should be adopted for future smart farm deployment.
Keywords: Energy models; Smart farm; Internet of Things; WSN; ZigBee; Evaluation
|77 – 83|
|10.||Kesan Ketebalan Filem Terhadap Fotoelektrokimia Titania Dioksida (TiO2) Yang Disediakan Melalui Kaedah Pemendapan Bantuan Aerosol Wap Kimia (AACVD)
Mohd Fairuz Soh-Yusoff, Mohamad Firdaus Mohamad Noh, Chin Hoong Teh, Norasikin Ahmad Ludin, Mohd Adib Ibrahim, Mohd Asri Mat Teridi* & Abd. Rashid Mohd Yusof
Titanium dioxide (TiO2) is a wide band gap semiconductor, which owing to its photoconversion properties in UV spectrum range shows various useful applications. In this study, aerosol-assisted chemical vapor deposition (AACVD) technique was employed to deposite TiO2
Keywords: Titanium Dioxide, Aerosol Assisted Chemical Vapor Deposition (AACVD); Film Thickness; Photoelectrochemical
|85 – 92|
|11.||A Study on Properties of Polymer-Based Additive Manufacturing
Zaliha Wahid*, Mohd Khairol Anuar Mohd Ariffin, B.T. Hang Tuah Baharudin, Faizal Mustapha & Mohd Idris Shah Ismail
In recent years, increasing interest in 3D Printing (3DP) has meant that printer usage is not limited to industrial purposes only, but is also for domestic usage by hobbyists for their individual needs. Polymer-based part production can now even be conducted outside the traditional factory environment. However, low grade printers pose some drawbacks, such as lower heat for material fusion, uncontrolled open ambience and limited nozzle size. These reduce the mechanical and aesthetical qualities as compared to parts fabricated using industrial grade printers. The study aims to perform some quality comparisons between 3D printed polymeric parts fabricated by both industrial and low cost printers, and subsequently to prove the hypothesis that the industrial grade printed part has a more reliable surface quality and mechanical properties. Specimens were fabricated using each printer type (Fused Deposition Modelling (FDM) represents the low cost printer and the Multi Jet Printer (MJP) is used for the industrial grade) and later tested for hardness and surface roughness. Comparisons were then made between different fabricating methods and also based on a literature study according to the type of materials. The experiments showed that both the surface roughness and hardness for the plastic parts fabricated by the industrial grade printer were better than those made by the domestic printer, and showed a good agreement with the results in the literature study. Therefore, for highly durable parts, it is suggested that industrial grade printers are used. One point to conclude the study, Rapid Prototyping is possible by any machine, but for Rapid Manufacturing that requires higher durability, it is better to use an industrial grade printer.
Keywords: Additive Manufacturing; 3D Printing; Rapid Prototyping; Polymer
|12.||Sistem Saringan Penyakit Pterigium untuk Imej Mata Terangkum Hadapan
Siti Nur Aishah Ahmad, Wan Mimi Diyana Wan Zaki* & Nurul Syahira M Zamani
Pterygium is an eye disease occurs when an overgrowth tissue encroaches into a cornea region of the eye. It commonly affects people who live near-equatorial areas such as Malaysia and being exposed to a condition with excessive wind, ultraviolet radiation or dust. One of the conventional ways of pterygium detection is a manual screening approach by ophthalmologists. Pterygium is diagnosed after a physical examination of the eyes is conducted. The eye images are photographed to monitor the growth of the pterygium tissues. If necessary, specialized diagnostic tests may be done, particularly when the pterygium extends onto the cornea regions. For instance, a corneal topography will be used to map the surface of the cornea to detect any distortions that may arise with a larger pterygium tissues growth. To the best of our knowledge, there are limited numbers of studies that applied digital image processing (DIP) approach to early detect this ocular disease using anterior segment photographed images (ASPIs). Hence, this project proposes an algorithm to identify pterygium disease using ASPIs obtained from four different databases that are UBIRIS, MILES, RAFAEL, and QPEI. The proposed screening system consists of 4 main modules namely ASPIs data collection, cornea segmentation, feature extraction and pterygium detection modules. By calculating the ratio of radius in the cornea segmented regions and using a threshold value of 1.00, the pterygium detection results give 90.60% True Positive (TP), 77.24% True Negative (TN), 22.76% False Positive (FP) and 9.40% False Negative (FN).
Keywords: Pterygium; Cornea; Digital Image Processing; Anterior Segment Photographed Image (Aspis); Screening System
|99 – 105|
|13.||Reactive-Active Power Control for Grid-Connected PV Arrays to Enlarge the Hosting Capacity in A Low Voltage Distribution System
Hamza Abunima, Jiashen Teh* & Hussein Jumma
The stochastic behavior of solar radiation is one of the challenges faced by increasing the hosting capacity of the photovoltaic (PV) power. At times of exceptional high PV power output, unacceptable voltage rise could happen at PV system terminals. Violating the voltage threshold adversely affect the power quality and security at the customer sides. In order to avoid this, the PV system is normally disconnected during high PV power output, thus causing losses in power generated. Local control approaches have been introduced as a measure to overcome this issue by using only the inverter. One of these approaches is to control the reactive power output of a PV unit in order to suppress the voltage rise without ceasing the PV system. The results from this paper have shown that the existing reactive power control (RPC) approach is unable to suppress this voltage rise effectively in case of low X/R ratio. Active power curtailment (APC) is another approach that results in remarkable power losses. Hence, this paper proposes a methodology that combines both RPC and APC approaches to limit the voltage rise in a low voltage distribution feeder. The effectiveness of the proposed methodology have been examined and demonstrated in this paper. The obtained results show the superiority of the proposed methodology over the conventional approaches, which enlarges the hosting capacity for PV power penetration in a low voltage distribution system.
Keywords: Reactive Power Control; Active Power Control; Photovoltaic; Voltage Rise
|107 – 114|
|14.||Prestasi Pemangkin Pt/rGO Menggunakan Teknik Susunan Berlapis untuk Elektrod Lawan bagi Sel Suria Terpeka Pewarna
Aisyah Bolhan, Norasikin Ahmad Ludin*, Najah Syahirah Mohd Nor, Mohd Adib Ibrahim, Suhaila Sepeai, Mohd Asri Mat Teridi, Kamaruzzaman Sopian & Azami Zaharim
The stacked layer technique of platinum (Pt) and reduce graphene oxide (rGO) counters electrode thin film fabricated by using doctor blade method was prepared. The first layer with direct intact on fluorine doped tin oxide (FTO) glass substrate was graphene thin film and second layer on top of graphene layer was Pt thin film. X-ray diffraction (XRD) and atomic force microscopy (AFM) were performed on the thin films to determine the formation of crystallite structure and the surface roughness of the thin films, respectively. The crystallite size was determined from XRD data and it shows that Pt/rGO-10 thin film has the suitable crystal size for a better catalytic activity. As for surface roughness analysis from AFM images, Pt and Pt/rGO thin films exhibit the rougher surface compared to rGO thin film. The thin films were further analysed using field emission scanning electron microscopy (FESEM) to observe the adhesion of Pt and rGO on FTO glass substrate in nanoscale image. The catalytic activity of each thin film was measured by cyclic voltammetry (CV). The Pt/rGO counter electrode of 10μl aqueous graphene oxide denoted as Pt/rGO-10 has high catalytic activity compare to Pt. The Pt/rGO-10 recorded the highest current density at -3.075 mA/cm-2 indicate a high catalytic activity at the counter electrode. Thus, Pt/rGO-10 counter electrode thin film deemed as comparable to conventional counter electrode material which is Pt. Therefore, Pt/rGO-10 counter electrode is expected to improve the performance of Dye-sensitized solar cell.
Keywords: Counter Electrode; Dye-Sensitized Solar Cell (Dssc); Graphene; Stacked Layer
|115 – 122|
|15.||Assessment of Factors Affecting Student’s Satisfaction and Loyalty on the Crossed Parking System at Residential Colleges of Universiti Kebangsaan Malaysia
Siti Khairunisa Zainal & Amiruddin Ismail*
An increase in the number of students studying in Universiti Kebangsaan Malaysia (UKM) (the National University of Malaysia) has led to increase parking facilities requirements at residential colleges. Some colleges applied crossed parking systems to address these problems. This study aims to ensure that parking facilities provided at UKM’s residential colleges are adequate in the future and explaining the impact of parking services on the satisfaction and loyalty of students. The primary data was obtained by calculating the parking turnover and questionnaire survey. Secondary data is obtained from the college’s management that implement cross parking systems, namely Keris Mas College (KKM), Rahim Kajai College (KRK) and Pendeta Zaaba College (KPZ). This study has two models, the model of adequacy level of parking facilities at college and parking service quality model on student satisfaction and loyalty. This study applies the SERVQUAL and Loyalty models. Then, observation data will be analysed using EXCEL and parking plans drawn using AUTOCAD. Questionnaires were analysed by the SEM method using SPSS and AMOS Graphic software. Observation studies produce several features and behaviours of crossed parking systems. The peak hours for KKM, KRK and KPZ start at 5.00 pm-8.00 am, 10.00 pm7.00 am and 6.00 pm-8.00 am where the number of vehicles exceeds the parking space provided. The maximum number of parking vehicles outside the bar and in the prohibited areas for KKM, KRK and KPZ are 134 and 25, 30 and 3 and 84 and 10 vehicles. This situation shows that crossed parking facilities provided are inadequate and at critical levels. Meanwhile, the questionnaire survey shows that the main determinants of parking services quality are tangible, reliability and assurance factor. These factors have a significant impact on service quality. Determinants that not significant which are reliability, responsiveness and empathy have been ignored. Finally, the respondents were dissatisfied with this parking system and refused to propose their friends to park vehicles in the crossbar area.
Keywords: Crossed Parking; Servqual Model; Student’s Satisfaction and Student’s Loyalty
|123 – 129|
|16.||Perception Towards the Performance of Outboard Motors Among Malaysian Coastal Fishermen in Manjung, Perak
Ismail Zainol, Omar Yaakob & Mohd Rajali Jalal
AFishermen, particularly those in coastal seas, are often categorized under low-income community. Many efforts have been taken to assist this community to sustain their livelihoods, but hampered by various factors such as high operational cost. Coastal fishing boats specifically made from fiberglass are greatly dependent on petrol-powered outboard motor to generate power. The high fuel consumption of outboard motors is believed one of the factors that contribute to their high operational cost. To this end, it is necessary to dive into the fishermen’s perception on this issue. This paper presents finding on the perception of coastal fishermen towards the performance of outboard motors and their views on fuel-saving engines. Some key areas are discussed and explained in this paper. A questionnaire had been developed as a survey tool; divided into three parts, covering cost factor, engine factor and operation factor. The questionnaire was developed based on Likert scale and distributed to randomly selected respondents among the fishermen community at Manjung, Perak. The data was then processed using Statistical Package for Social Science (SPSS). The results showed that inshore fishermen are not satisfied with petrol outboard motor, with more than 95% confidence level.
Keywords: Coastal Fisheries; Outboard Motors; Fuel Consumption
|131 – 137|
|17.||Computational Fluid Dynamics Simulation on the Heat Sink Performance of a Graphics Processing Unit Thermal Management
Zambri Harun*, Ng Jie Suang, W. M. Faizal W. Mahmood, Mahir Faris Abdullah & Eslam Reda Lotfy
The article focuses on the numerical investigation of temperature distribution in a central processing units (CPU) case with different time interval such as t = 100 s, 200 s, 300 s, 400 s, 500 s. Heat sink performance of a graphics processing unit (GPU) thermal management and impacts of different shape and velocity on the thermal performance are considered. In this study, three heat sink models are designed (A, B, and C) based on the volume area of heat sink. This study emphasizes the heat transfer phenomena caused by a GPU in a computer case in both steady state and transient state. A CFD software STAR – CCM + is used to carry out to study the fluid flow and heat transfer simulation of graphics card heat sink in a computer case and the same time an enhanced method of reducing the temperature of GPU is proposed. The results show that heat sink B with the least volume area, has the fastest rate of heat exchange followed by heat sink C and heat sink A. Likewise, the result indicates an inverse relationship between the volume and the total surface of the heat sink and the final temperature of the graphics card chip. As the total volume and surface of the heat sink increases, the rate of heat transfer increases via faster rate of conduction between graphics card chip to heat sink meanwhile the cooling of the heat sink is aided by wind inlet via convection.
Keywords: Heat Sink; Heat Transfer; Steady State; Transient State
|139 – 147|
|18.||Reactivity Controlled Compression Ignition Engine: A Review
Zuhairizan Yusof, Siti Umairah Mohamed Radzwan, Zuzailie Rosli, Aldaedin Alaa Razzaq Abdulmohsin & Mohd Radzi Abu Mansor*
Reactivity Controlled Compression Ignition (RCCI) is an efficient dual-fuel engine combustion technology that can offer low emission level in internal combustion engine technology. RCCI technology works by generating reactivity stratification in the cylinder with two fuels of different cetane numbers. To accomplish reactivity stratification, the fuel with lower reactivity is premixed with air before charging into the combustion chamber. The fuel with higher reactivity is injected subsequently using a direct injector. By properly manipulating the fuel ratio and the injection timing, one is able to regulate the combustion phasing and lessen the rates of pressure rise and heat release thanks to the reactivity gradient. Meanwhile, factors such as compression ratio (CR) and piston bowl geometry could influence the characteristics of RCCI. Evaporation, mixing, and combustion processes are dependent on the fuel type. In this paper, recent progress to improve the combustion processes with several aspects of changing of RCCI engine parameter are reviewed, such as management strategy, compression ratio, EGR rate, and bowl geometry.
Keywords: High Reactivity Fuel; Low Reactivity Fuel; Engine Management; Cetane Number; Injection Strategy
|149 – 153|
|19.||Hydrogen Production from Catalytic Formic Acid Decomposition over Zn Based Catalysts under Room Temperature
Masitah Abdul Halim Azizi*, Wan Nor Roslam Wan Isahak, Norliza Dzakaria & Mohd Ambar Yarmo
The depletion of petroleum sources and global warming issues has increased awareness among scientists to produce alternative energy other than the one that we always depend on, which is petroleum. Hydrogen (H2) energy is one of the alternatives that was promising as an efficient and green fuel. Meanwhile, formic acid has been detected as one of the convenient H2 source/storage material. Here, we introduce two heterogeneous catalysts for H2 generation from formic acid. Fe0.1 Zn0.9 and Fe0.5 Zn0.5 were synthesized by a modified microwave method. In this study, we report the result of a detailed study undertaken to investigate the decomposition of formic acid to H2 and carbon dioxide (CO2) using gas chromatography with thermal conductivity detector (GC-TCD). The catalyst used to decompose the formic acid was characterized by x-ray diffraction (XRD) to determine their physicochemical properties. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) were also used to determine the surface morphology and the structure of the synthesized catalysts. The result suggested that in the dehydrogenation reaction, 90-96% of H2 was selectively produced from the formic acid with the presence of FeZn catalyst. For Fe0.1Zn0.9 catalyst, FESEM micrograph shows the particle was well dispersed, existing both away from and close proximity to 50-70 nm in size. Both heterogeneous catalysts are able to produce H2 from formic acid at room temperatures (30°C) with no additives added and with high selectivity.
Keywords: H2 Energy; Fezn Catalyst; Formic Acid Decomposition; Microwave-assisted Method; H2 Selectivity
|155 – 160|
|20.||Penilaian Kitaran Hayat Sel Suria Terpeka Pewarna di Malaysia
Nur Ifthitah Mustafa, Norasikin Ahmad Ludin*, Mohd Adib Ibrahim, Azami Zaharim & Norani Muti Mohamed
Solar energy is the most abundant nature resources on earth which easily exploitable, clean, long lasting and dependable which make it is desirable to generate electricity compared to other energy resources. However, conventional solar photovoltaic (PV) technologies such as silicon and thin film solar cells may provide significant environmental impacts over their life cycle due to complicated production process of these PV technologies. This make numerous scientists looking forward on the new emerging solar cells including dye sensitized solar cell (DSSC). Thus, the objective of this research is to analyse a comprehensive environmental impact assessment through life cycle assessment (LCA) from cradle-to-gate approach of this technology in Malaysia. Two environmental indicators were evaluated such as cumulative energy demand (CED) that affect the energy payback time (EPBT), and greenhouse gas (GHG) emissions. The results highlight that DSSC module has EPBT of 3.49 years, CED of 1190.29 MJ/m2 and GHG emissions of 262.38 gCO2eq/kWh which were slightly higher compared to other researchers. Higher energy consumption in module fabrication and panel manufacturing process, lower conversion efficiency (ŋ) and solar irradiation (IR), and used of FTO glass substrate were recognized as main contributors to the results.
Keywords: Cumulative Energy Demand (CED); Dye Sensitized Solar Cell (DSSC); Energy Payback Time (EPBT); Greenhouse
|161 – 168|
|21.||Detection of Back-Scattered Signal for Optical Fibre Resonant Scanner
Juwadi Prak Ser, Lee Chia Cheng, Farah Shahrim, Ahmad Ashrif A Bakar & M. H. H. Mokhtar
We report the development of optical fibre resonant scanner that was developed using two multi-mode optical fibres that are attached side-by-side, producing a cantilevered optical fibre scanner. The optical fibre is mounted on photodiode and a small piezoelectric disk using polymer. The piezoelectric disk is driven with a sinusoidal signal that will then vibrate the mounted optical fibre, producing a single axis scan line. This paper reports on experimental detection of the back-scattered signal through dual-numerical aperture conFigureuration and identification of fibre position from a single scan line with respect to the optical reflections from the apertured reflector. The apertured reflector used was a brass metal with 1 mm of diameter that is placed before the imaging lens as a mechanism to differentiate the position of scan line. The single scan was obtained at its maximum length of 4.8mm with resonant frequency of 2.033kHz. The back-scattered signal from a target object is coupled back into the cladding of the optical fibre. The cladding mode is then stripped and detected by photodiode. The back scattered signal from the aperture is used to differentiate the position of fibre between the aperture and the target object itself. Differences in the position of the slots resulted pulses with different height and width, allowing the two backscattered signals to be distinguished. The experimental result is verified and compared with the theory back-scattered signal produced by such scanner.
Keywords: Endoscopic Imaging; Fibre Scanner; Optical Imaging
|169 – 175|
|22.||On the Bachelor Program in Engineering Physics for Underdeveloped and Developing Countries: Vision for Global Competitiveness
Gunawan Nugroho* & Aulia Nasution
The importance of a Bachelor Program in Engineering Physics for underdeveloped and developing countries is discussed in this paper. Worldwide rapid developments need reliable engineering graduates with strong inter- and multidisciplinary academic qualifications. Anticipating this requirement, Bachelor degree program in engineering physics is regarded as the most suitable for preparing graduates in underdeveloped and developing countries with such qualification profile. Several studies showed that the need for such educational program is quite promising. The motivation to strive for higher qualifications is strong, and it is motivated by individual as well as the institutional consciousness, as also triggered by labor market requirements and government’s incentives. It is not surprising that the similar qualification profiles are already well designed in many industrial countries for Master up to PhD levels. Since the program requires a cross-discipline study among many fields, this paper also discusses the synergistic clustering strategy for facilitating the learning, research, and developmental activities. In this paper, seven clusters are proposed, namely generic knowledge, basic knowledge, instrumentation and control, energy and environmental engineering, materials, acoustics and vibration, and photonics. The cluster courses can be distributed in each semester depends on the department strategy of achieving the learning outcomes. Mandatory courses for such program are also being addressed as well.
Keywords: Engineering Physics; Bachelor Program; Inter- and Multidisciplinary Academic Qualifications
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