UniMAP RIS :: Browsing Publications 2018 by Issue Date

Publication

On body characterization for on-body radio propagation channel using wearable textile monopole antenna

( 2017-01-01)

Rahim H.A.

;

Malek F.

;

Soh P.J.

;

Hisham N.

;

Romli A.

;

Rani K.A.

;

Isa C.M.N.C.

;

Fuad F.A.A.

This paper presents the experimental investigation of the characterization of the narrowband on-body radio propagation channel at 2.45 GHz. Wearable planar textile monopole antennas (TM) were used in this measurement campaign. The measurements were conducted in the RF-shielded room environment, considering eight on-body radio links. A statistical analysis was conducted on the spectral parameters of the channel to enable the prediction and modeling of dynamic on-body radio propagation characteristics. The empirical data were fitted to several well-known statistical models to determine the model that provided the best fit for the data. The results showed that the path loss exponent was consistent with the results of previous studies. The results also demonstrated that lognormal distribution was found to be the best fit for path loss in dynamic on-body radio propagation channel.

Publication

Atmospheric pressure plasma jet treatment of Malaysian batik fabrics

( 2017-01-01)

Elfa R.

;

Rahizan U.

;

Ahmad M.

;

Soon C.

;

Sahdan M.

;

Lias J.

;

Abu Bakar A.

;

Md Arshad M.

;

Hashim U.

;

Nayan N.

Atmospheric pressure plasma jet became very popular in plasma chemistry due to its properties which are applicable for surface treatment. In this work, a low-cost and in-house atmospheric pressure plasma jet using argon gas, neon transformer power supply and quartz tube has been developed. The atmospheric pressure plasma jet system can be used for textile applications. The low temperature of plasma treatment is environmentally friendly technology which has been proposed to change the topographical properties of the textile surface, besides its popularity that can be used to improve the surface wettability and dying properties of the textiles. Malaysian batik fabric has been used in this work to study the treatment effect of plasma jet on fabrics. Contact angle measurement is used to observe the water contact angle and absorption time under various treatment conditions. Results show that the fabric surface became hydrophilic just after the treatment of plasma jet. The water absorption time became faster when exposed to longer treatment time and higher flow rate of argon flow. This understanding is essential to optimize the usage of atmospheric pressure plasma jet for textile treatment and modification.

Publication

Climatic parameters and vegetation effect on wireless routing pattern in greenhouse

( 2017-04-01)

Harun A.

;

Mohamed Farook R.S.

;

Kamarudin L.M.

;

Jaafar M.N.

;

Murad S.A.Z.

;

Isa M.N.

;

Husin Z.

;

Aziz A.A.H.

;

Hambali N.A.M.A.

One of the promising areas where wireless sensor network (WSN) application would be essential is in precision farming, especially those involving high value crops. Understanding the behavior of the signal propagates in such environment would be crucial in optimizing the wireless sensor nodes deployment. This paper discusses the experimental implementation of wireless sensor network in mango greenhouse and the effect of climatic parameters and vegetation on the routing pattern of the nodes. The results show that the number of hops increases as an effect of variation in climatic parameters. Nevertheless, the changes in temperature alone do not seem to affect the changes in the pattern of signals routed in the greenhouse significantly contrary to the changes in humidity level. As humidity level decreases, the number of signal routing increases, thus showing more chaotic routing pattern. The presence of vegetation around the nodes helps to preserve humidity level, thus increasees the creation of low cost path for signal to be undertaken, which in the end added to the number of signal hops.

Publication

Textile Antenna with Simultaneous Frequency and Polarization Reconfiguration for WBAN

( 2017-12-22)

Salleh S.M.

;

Jusoh M.

;

Ismail A.H.

;

Kamarudin M.R.

;

Nobles P.

;

Rahim M.K.A.

;

Sabapathy T.

;

Osman M.N.

;

Jais M.I.

;

Soh P.J.

This paper proposes the design of a reconfigurable circularly polarized textile antenna. The circular polarization feature in the proposed antenna is generated by the edge truncation of a rectangular patch and the incorporation of a slotted ground plane, whilst the frequency reconfigurability feature is realized by slot size modification via the use of three embedded RF p-i-n diode switches. Consequently, the antenna operation can be switched between six frequencies (1.57, 1.67, 1.68, 2.43, 2.50, and 2.55 GHz) depending on the seven switch configurations. The proposed antenna is validated experimentally to be operable within the WBAN, WLAN, and GPS range in a compact and wearable format, with gains of up to 4.8 dBi.

Publication

Silicon Carbide Nanomaterials

( 2018-01-01)

Voon C.H.

;

Lim B.Y.

;

Ho L.N.

In recent years, SiC nanomaterials have been studied extensively owing to their unique and novel properties. This chapter provides a thorough description of recent advances in the synthesis, properties, and applications of SiC nanomaterials. The chapter begins with the highlights of the synthesis and fabrication of SiC nanomaterials, ranging from SiC nanoparticles to three-dimensional complexed SiC nanomaterials. The effects of various processing parameters on the size and morphologies of SiC nanomaterials are also illustrated in this section. This is followed by an exploration of the unique properties of SiC nanomaterials, including mechanical, electrical, thermal, and optical properties. Next, the applications of SiC nanomaterials, which exploit their unique and novel properties, are presented; these include composites, sensors, nanoelectromechanical systems, catalyst, field effect transistors and hydrogen storage. This chapter ends with concluding remarks that focus on the current progress and upcoming challenges of SiC nanomaterials research.

Publication

Influence of tool plunge depth on the joint strength and hardness of friction stir welded AA6061 and mild steel

( 2018-01-01)

Wan Sulong W.M.S.

;

Rojan M.A.

;

Mazlee M.N.

The purpose of this paper is to investigate the impact of the tool plunge depth on the mechanical properties of friction stir welding (FSW) of AA6061 and mild steel. In FSW, welding is performed using a non-consumable rotating tool that is allowed to plunge in between two plates in a butt joint and travel along the abutting line. The tool plunge depth determines how deep the pin and shoulder of the tool penetrates the surface of the plates. Tensile testing was performed to determine the influence of plunge depth at different tool travel speeds on joint failure strength. Also, the formation of defects and its relationship with plunge depth were also investigated. Vickers microhardness testing was also done on weld cross sections to study plunge depth’s effect on hardness.

Publication

Reconstruction of Medical Images Using Artificial Bee Colony Algorithm

( 2018-01-01)

Rusdi N.A.

;

Yahya Z.R.

;

Roslan N.

;

Wan Muhamad W.Z.A.

The goal of this study is to assess the efficiency of Artificial Bee Colony (ABC) algorithm in finding the optimal solution of curve fitting problem specifically for medical images. Data of Computed Tomography (CT) images from two different patients were collected. The procedure of curve fitting for medical images include conversion of Digital and Communications in Medicine (DICOM) images to binary images, boundary and corner point detection, parameterization, and curve reconstruction by using ABC algorithm. Then, Sum Square Error (SSE) was used to calculate the distance of the fitted Cubic Bezier curve with the boundary of the original images. Based on the calculation and parameter tuning that had been done, the smallest error of both skulls is 57.5754 and 28.8628, respectively. The finding of this study illustrated that the proposed method had efficiently produced fitted Bezier curve that resemble the original medical images. In addition, the used of Douglas Peucker algorithm helps to improve the performance of the proposed method since computational time can be minimized. This study had shown that the proposed method can be used as an alternative method in order to reconstruct or redesigned the medical images since it produces a small error. For future work, we are planning to explore and applied the ABC algorithm to reconstruct the missing part of the skull since it can reduce the time taken to produce the skull implant as well as reducing the cost of producing it.

Publication

Cyclist performance classification system based on submaximal fitness test

( 2018-01-01)

Sudin S.

;

Shakaff A.

;

Zakaria A.

;

Salleh A.

;

Saad F.

;

Abdullah A.

Performances among cyclist always measured by time traveled from start to finish line and then the winner in cycling event also decided by time or who crossed the finish line first. On the other hand, cyclist performance can be measured through cardiorespiratory and physical fitness, and this performance can be enhanced by proper training to increase fitness and skill without burden. A wireless sensor network (WSN) system developed by combined various sensing element to capture physiological and bicycle's kinetics feedback. Physiological data such as heart rate variability (HRV) and kinetic data such as paddling power and cadence used as input in Astrand-Ryhming and PWC150 submaximal test to classify the performance group among cyclist. Developed HRV system using Photoplethysmography (PPG) provides the significant output with R2 value was 0.967. A group of 15 cyclists from three different backgrounds was used as a subject in this study. Maximal oxygen intake (VO2max) produced by Astrand-Ryhming test correlated with estimated paddling power produced by PWC150 test with P<0.01 and the R2 value was 0.8656. Discriminant analysis was 88.3% successfully classified cyclist into 3 group and group of trained and untrained cyclist clearly separated.

Publication

Dual axis solar tracking system in Perlis, Malaysia

( 2018-01-01)

Zulkafli R.S.

;

Bawazir A.S.

;

Amin N.A.M.

;

Hashim M.S.M.

;

Majid M.S.A.

;

Nasir N.F.M.

Sunlight is an abundant source of energy and this energy can be harnessed successfully using solar photovoltaic panels and convert it into electrical energy. However, the conversion efficiency of a normal PV panel is low. One of the main reasons is the power output of a PV panel is dependent directly on the light intensity. As the position of the sun is changing continuously from time to time, the absorption efficiency of an immobile solar panel would be significantly less at a certain time of the day and year. Therefore, to maximize the energy generation and improve the efficiency, a solar tracker comes into play. This paper presents the design and construction of an inexpensive active dual axis solar tracking system for tracking the movement of the sun to get the maximum power from the solar panels. It uses Light Dependent Resistors (LDR) to sense the position of the sun which is communicated to an Arduino Uno microcontroller. An algorithm is implemented to control DC geared motor's movements which maintaining the solar PV panel position so that it will perpendicularly facing towards the sun at all the effective time. Performance for both fixed and dual-axis solar tracker was compared. Evaluation results show that the dual-axis solar tracking system performs 44.7% better than the fixed solar tracking system.

Publication

An effect sensitivity harmonics of rotor induction motors based on fuzzy logic

( 2018-01-01)

Aryza S.

;

Irwanto M.

;

Khairunizam W.

;

Lubis Z.

;

Putri M.

;

Ramadhan A.

;

Hulu F.N.

;

Wibowo P.

;

Novalianda S.

;

Rahim R.

The stator is apart complicated because it is one of the main parts of mechanical components inside an induction motor and is often a heat problem in the electrical pressure and also due to competitive environmental conditions, etc. So this study discusses how the tech-nique used in identifying the initial level of small error rate in the induction motor. Several studies also discuss motor vibration detection analysis. So this research is done about the harmonization of rotation causing this vibration amplitude which causes problems of mechan-ical stress and motor. So that the results of this research can be a result of learning about the effect of error amplitude, causing problems in the rotor and fuzzy logic results performed also resulted in increased amplitude of vibration in rotor harmonics.

Publication

Comparative prediction of red alga biosorbent performance in dye removal using multivariate models of response surface methodology (RSM) and artificial neural network (ANN)

( 2018-01-01)

Mokhtar N.

;

Aziz E.A.

;

Aris A.

;

Ishak W.F.W.

;

Majeed A.P.P.A.

;

N.Moni S.

;

Sa'at S.K.M.

Red algae species, Euchema Spinosum (ES) in Malaysia possesses excellent biosorbent properties in removing dyes from aqueous solutions. In the present study, the experimental design for the biosorption process was carried out via response surface methodology (RSM-CCD). A total of 20 runs were carried out to generate a quadratic model and further analysed for optimisation. Prior to the evaluation, the characterisation study of the ES was performed. It was observed that the maximum uptake capacity of 399 mg/g (> 95%) is obtained at equilibrium time of 60 min, pH solution of 6.9-7.1, dosage of 0.72 g/L and initial dye concentration of 300 g/L through statistical optimisation (CCD-RSM) based on the desirability function. It is demonstrated in the present study that the ANN model (R 2 = 0.9994, adj-R 2 = 0.9916, MSE = 0.19, RMSE = 0.4391, MAPE = 0.087 and AARE = 0.001) is able to provide a slightly better prediction in comparison to the RSM model (R 2 = 0.9992, adj-R 2 = 0.9841, MSE = 1.95, RMSE = 1.395, MAPE = 0.08 and AARE = 0.001). Moreover, the SEM-EDX analysis indicates the development of a considerable number of pore size ranging between 132 to 175 μm. From the experimental observations, it is evident that the ES can achieve high removal rate (> 95%), indeed become a promising eco-friendly biosorptive material for MB dye removal.

Publication

Synthesis and characterization of Ag/Tio2thin film via sol-gel method

( 2018-01-01)

Halin D.S.C.

;

Abdullah M.M.A.

;

Mohd Salleh M.A.A.

;

Mahmed N.

;

Mohd Sakeri A.N.

;

Abdul Razak K.

Ag/TiO2thin films were prepared via sol-gel spin coating method. Structural, surface morphology and optical properties were investigated with the addition of two different amount of silver (Ag). X-ray diffraction pattern shows the sample with pure TiO2, the only phase presence was brookite TiO2. When the Ag content added into the solution, the phase existed for the samples with TiO2doped 0.5g Ag and TiO2doped 1.0g Ag were anatase TiO2with no peak corresponds to Ag phase. The surface morphology of film was characterized by scanning electron microscopy (SEM). The films were annealed at 450 °C and it shows non-uniform films. The films have a large flaky and cracks film which was attributed to surface tension between the film and the air during the drying process. When the solution of sol was added with Ag content, it shows the porous structure with flaky-crack films. With the increasing of the Ag content from 0.5g to 1.0g, the structure is more porous and it is good for the photocatalytic activity. The UV-Vis spectra shows that the film exhibits a low absorbance which was due to the substrate is inhomogeneously covered by the flakycrack films.

Publication

Composting of garden waste using indigenous microorganisms (IMO) as organic additive

( 2018-01-01)

Khalib S.N.B.

;

Zakarya I.A.

;

Izhar T.N.T.

Garden waste (GW) is considered as one of the types of municipal solid waste because of its biodegradable organic fraction. To avoid the disposal of green waste by open burning, incineration and landfill site, it can be manage by composting process. The objective of this study was to evaluate the performance of composting garden waste (dry leaves) by using indigenous microorganisms in term of the compost quality (pH, temperature, moisture content, C:N ratio and nutrient content). The compost has been prepared from three different mixtures of food waste for 30 days. IMO used as an organic additive during composting were prepared according to the method from previous study. The preparation of IMO consists of several phases include phase I until V with a mixture of various materials for each phase. During the composting process, all the parameters of IMO-compost obtained in a range like; pH value 8-9, temperature 30-48°C, moisture content 36-65%, nitrogen 2- 7%, phosphorus 4-8%, potassium 12-18% and C:N ratio 6-12. The result showed that all compost quality for IMO-compost obtained in an acceptable range for final compost to establish.

Publication

Breast surface coordinate variation analysis caused by round shape tumor with fringe projection profilometry

( 2018-01-01)

Norhaimi W.

;

Vairavan R.

;

Sauli Z.

;

Retnasamy V.

;

Aziz M.

;

Aris H.

;

Shahimin M.

Breast cancer is one of the fatal diseases and is one of the leading causes of death among women. Early screening for breast cancer is highly needed among women. Monitoring of the disease is also extremely vital for determining the best possible method of treatment. One of the most common symptoms of breast cancer is the breast surface change caused by the tumor within the breast. Shapes of the tumor vary among the patients, and some of the standard shapes of the tumor are round, oval, irregular, spiculated and microlobulated. Current common imaging modalities of diagnosing for breast tumor is the Magnetic Resonance Imaging (MRI), ultrasound and mammography. The current imaging modalities have been known to diagnose the disease but also has its limitations due to exposure concerns. In this work, the changes of breast surface are analyzed using a proposed fringe projection imaging modality. Surface changes of the breast were analyzed with the presence of a round shape tumor varied from 0.5 cm to 2 cm. The fringe projection profilometry system has successfully demonstrated its ability in detecting the pixel coordinate changes of the breast surface caused by the size variation of the tumor.

Publication

Development of miniature compressed air storage system using solenoid valves for dynamic pneumatic actuator

( 2018-01-01)

Najmuddin W.S.W.A.

;

Mustaffa M.T.

;

Awang A.H.

;

Hussain S.

Currently, there are many research that involved pneumatic device on vehicles. There are some applications using compressed air storage system to produce vehicle power. However, there are several constraints in producing compressed air for outdoor purpose, since most of the compressors are in large size which will cause limited working space. Also, most of the compressors are not portable and hand-carrying size. This paper objective is to investigate the parameters of a miniature air compressor during the reciprocation process and to analyze the compressed air pressure of piston type double-acting cylinder for the miniature air compressor. The piston rod is connected to connecting rod for mechanical movement, which the movement of the rod will convert kinetic energy to the piston and generate compressed air inside the storage tank. The system design allows the air into the tank to increase via reciprocating cylinder. Number of strokes produced is investigated. Subsequently, pressurized air inside the tank can be used to generate kinetic power to the pneumatic actuator. The force generated from the mechanism is then measured. Synchronization of 5/3 Ways Directional Control Valves (DCV) is the key of the system to ensure the flow of compressed air well-kept in the storage tank. The pressurized air inside the tank transfers the power into kinetic movement via reciprocating piston and able to generate 200kPa of compressed air.

Publication

Elastic interactions of osteon-crack penetration in longitudinal fracture

( 2018-01-01)

Mansor N.N.

;

Daud R.

;

Basaruddin K.S.

;

Bajuri Y.

;

Ariffin A.K.

Longitudinal fracture of cortical bone involves complex elastic interaction between interstitial matrix, cement line, osteon and Haversian canal. Based on Kachanov theory of microcrack and hole interaction, there is effective impact interaction between different elastic moduli, and interaction between stress risers. This paper aims to numerically evaluate the effect of different Young's modulus in osteonal system structure for four-phase constituents (anterior, posterior, medial and lateral) in Haversian bone system particularly in longitudinal crack direction. The interaction between single crack and Haversian canal in crack-osteon penetration process is analysed based on linear elastic fracture mechanics (LEFM) with plain strain condition. Stress interaction intensities are compared to Brown and Srawley empirical formulation. The simulation results showed that the elastic interaction before the osteon penetration is consistent and stable.

Publication

Effect of moisture content in beef on reflection and dielectric measurement using coaxial reflection probes

( 2018-01-01)

Cheng E.M.

;

Lam C.K.

;

RahimAtSamusuddin H.A.

;

Mohd Nasir N.F.

;

Abdul Majid M.S.

;

Khor S.F.

;

You K.Y.

;

Lee Y.S.

Open-ended coaxial probe and Agilent 85070E High Temperature Probe were used in conjunction with Agilent E8362B PNA Network Analyzer from 200 MHz to 20 GHz for moisture detection in beef. The open-ended coaxial probe was fabricated from SMA stub contact. A high-temperature probe was used to measure dielectric properties, ϵ∗ viz. dielectric constant, ϵ′ and loss factor, ϵ″ of beef. Complex reflection coefficient, Γ was measured for different moisture content (mc) of beef. It would be compared with the measured Γ from High Temperature Probe to verify the performance of coaxial probe. ϵ′ increases when mc increases. However, ϵ″ exhibit opposite response with mc. Measured |Γ| via both probes decreases when frequency and mc increases. Meanwhile, negative phase, - φ increases due to the increment of frequency or mc. The results show that measured ϵ and Γ provides significant results for predicting mc. However, φ is indistinguishable among different mc of beef.

Publication

The relationship between the characteristics of innovation towards the effectiveness of ict in Malaysia productivity corporation

( 2018-01-01)

Hatimtai M.H.

;

Hassan H.

This study aims to investigate the relationship of innovation characteristics and demographic factors on the effectiveness of information and communication technology (ICT) utilization in Malaysian Productivity Corporation (MPC). The specific objective of this study is to understand the relationship between innovation characteristics and demographic factors in influencing the level of innovation adoption and which factors are most dominant in influencing the effectiveness of ICT. Using purposive sampling, a total of 210 respondents was selected consisting of MPC headquarters and 5 MPC branches throughout Malaysia. Data and information were collected using questionnaires. Quantitative data were analyzed using Pearson correlation statistical analysis, t-test and ANOVA. The findings showed that there is a significant relationship between innovation characteristics such as relative advantages, compatibility, complexity, observability and triability with the effectiveness of ICT in MPC. Observability has been identified as the major factor with the effectiveness of ICT in MPC with variants of 49%. The results of the analysis also proved that there is no significant difference between demographic factors with the effectiveness of ICT. The result also showed that age and level of academic is not a factor affecting the use of ICT in MPC. This has been proven by the findings of this study that the majority of respondents used ICT between 5 to 7 hours a day and 131 respondents has over 9 years of experience using computer at MPC. This finding suggests that innovation characteristics influenced the acceptance of innovation and will be the determinants of quality in an organization.

Publication

The design of ultra-high frequency (UHF) radio frequency identification (RFID) reader antenna

( 2018-01-01)

Hoon W.F.

;

Seok Y.B.

;

Malek M.F.A.

;

Seng L.Y.

;

Ibrahim S.Z.

;

Yasmin S.

This paper presents the design of ultra-high frequency (UHF) radio frequency identification (RFID) reader antenna using low dielectric constant of microwave substrate. An RFID reader antenna emits electromagnetic signals to the microchip in the tag, and the microchip will be energized by modulating the wave and returns to the reader antenna. The process of wave emitting is known as backscattering due to the presence of tag been detected by the reader. High-dielectric constant substrate, for example flame-retardant-4 (FR4) which is commonly used for microstrip patch antenna, is high in dielectric constant and dielectric loss. Thus, this will lead to low gain and directivity properties of the antenna. To overcome this matter, low-dielectric constant substrate which is Taconic TLY-5 was proposed to be utilized for microstrip patch antenna design. The TLY-5 microstrip substrate thickness used is 1.6 mm, dielectric constant of 2.2, and loss tangent of 0.019. A high-conductivity metal which is typically a conductive copper is been used for the two layers of dielectric substrate, the top radiating patch layer and bottom ground layer where the copper thickness is 0.035 mm. Microstrip feed line is used for this UHF RFID reader antenna. The width of the feed line was tuned to obtain impedance matching of 50 Ω. The proposed antenna which is fork-shaped patch antenna was simulated using Computer Simulation Technology (CST) and Microwave Studio software at resonant frequency of 910 MHz with the outcome results of 7.985 dB gain and −11.11 dB return loss. Nevertheless, the typical value obtained for VSWR is less than 2.

Publication

Stiffness of bolted timber connection

( 2018-01-01)

Rahim N.

;

Raftery G.

;

Quenneville P.

The stiffness equation for connections using fasteners in Eurocode 5 is specified as a function of wood density and fastener diameter only. In this research, an analysis of available data sets on various configurations of tested bolted timber connections has been undertaken in order to predict the initial stiffness of each connection. From the analysis, it is indicated that the stiffness equation specified in Eurocode 5 for bolted timber connections does not adequately predict the initial stiffness. There is a need to incorporate other connection parameters such as geometry into the equation to improve accuracy. Furthermore, in this research, numerical models have been developed to study the stiffness of bolted timber connections loaded parallel-to-grain. From these models, numerical predictions of the stiffness values have been made for various densities, diameters, end distances, row and bolt spacings and thicknesses of the timber members. An analysis of the results has shown that the stiffness of bolted timber connections is strongly dependent on the wood density, fastener diameter, bolt spacing, end distance and thickness of timber member where the greater the density, diameter, bolt spacing, end distance and thickness of timber member, the higher the stiffness value of the bolted timber connection. A relationship for the determination of bolted connection stiffness as a function of the steel - wood - steel connection configuration is presented. The results obtained in the experimental tests are compared with those obtained from the design models. Based on that analysis the accuracy of the predictions is discussed.

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