bluuebunny/crossref_metadata_2025 huggingface dataset:
Monthly Variations of Global Wave Climate due to Global Warming
Authors: Zikra Muhammad , Hashimoto Noriaki , Mitsuyasu Kodama , Sambodho Kriyo
Published: September 2015

Over recent years, ocean wave climate change due to global warming has attracted a lot of attention not only coastal and offshore engineer but also stakeholders in the marine industry. There is a wide range of application in ocean environment that require information on ocean wave climate data, such as ships design, design of offshore platforms and coastal structures or naval industry. In this research, monthly variation in significant wave height is studied using MRI-AGCM3.2 wind climate data for 25 year period from 1979-2003. The 25 year significant wave height simulation derived from JMA/MRI-AGCM wind climate data. The JMA/MRI-AGCM climate data were input into WAM model. The results showed that the monthly variability of significant wave height in the Northern Hemisphere is greater than in the Southern Hemisphere. Meanwhile, most of the equatorial regions are in calm condition all year.
Super Yatch Design Study for Malaysian Sea (Langkawi Island)
Authors: K. K. Koh , M. I. H. M. Ibrahim , A. S. A. Kader , P. Agoes , Rahimuddin Rahimuddin , M. N. Arib , U. I. Zan , K. B. Lok , J. Y. Wira , A. B. Mohd Noor , M. A. G. Pauzi , A. Maimun
Published: September 2015

Malaysia as a country surrounded by water has a huge economic and geographical potential in the development of super yacht industry in South East Asia. There is lack of super yacht design study specifying to Malaysian marinas and seas. Most of the super yacht operates in Malaysia were built and bought directly from oversea, and chartered by foreign companies. It is hence the purpose of this study to survey on Malaysian sea water, particularly Langkawi Island, to introduce a design methodology in producing a preliminary design of super yacht that suits Langkawi Island, and serves as a guideline for future super yacht design for Malaysian sea in different marinas. Suitable dimensions of super yacht were derived by using dimensional relationship via statistical method. Two types of hull form designs (round bilge and V-bottom hull) were designed using Maxsurf Pro software. Resistance analysis on the two hull forms were carried out using Savitsky Pre-Planing and Compton methods via MaxsurfHullspeed software, and stability performance of the two hull forms was analyze using Hydromax software. V-Bottom hull form is found to have better resistance performance as compared to round bilge hull form, and both hull forms are found to be in stable conditions and comply with IMO requirements.
Buckling Criteria for Subsea Pipeline
Authors: J. Abdul Khair, , Koto Jaswar, , Effendi Affis , Fitriadhy Ahmad
Published: September 2015

Oil and gas production in subsea operation continues to the extreme depth. Harsh environment and severe operation of oil and gas transportation due to high pressure and temperature become crucial for pipeline transportation. Consequently, The pipelines will deform to buckle shape which affect to integrity of pipeline. This phenomenon should be considered in design of pipeline to provide reliability of pipeline operation during time life period. The design result of pipelines is according to DNV F 101 whereas the magnitude of pipeline curvature will validate by ANSYS 14 to ensure pipeline reliability.
CFD Simulation of Water Gravitation Vortex Pool Flow for Mini Hydropower Plants
Authors: Shabara H. M. , Yaakob O. B. , M. Ahmed Yasser , Elbatran A. H.
Published: September 2015

Mini hydropower plants can be expected to have a good potential to provide electricity to remote communities. An important part of this economic and clean energy system is the conversion of the low-head potential energy into kinetic energy to drive the power turbines.  One way of converting the low-head potential energy is using a gravitation vortex pool. This paper describes work to optimize the vortex pool to improve energy conversion and hence generate electricity from low heads of between 0.7 m to 3 m. The commercial Computational Fluid Dynamics (CFD) code ANSYS Fluent was used in this study to investigate the optimum configuration of the vortex pool system. The free surface flow of this system was mathematically described. A parametric study was carried out using the software to determine the main parameters affecting the efficiency of the energy conversion. This parametric study utilized Fluent, which focused on the effect of changing water depth and outlet diameter on inlet/outlet speed; which is novel approach. The results from this study could help in the investigation of the optimum configuration of the vortex pool system.
Review of Micro-bubble Ship Resistance Reduction Methods and the Mechanisms that Affect the Skin Friction on Drag Reduction from 1999 to 2015
Authors: Hashim Azlina , Yaakob O. B. , Koh K. K. , Ismail Nasrudin , M. Ahmed Yasser
Published: September 2015

In order to lower down the fuel consumption and to achieve higher speed of ship, reduction in ship resistance has been the major topic of research for a long time. The most important factor in ship resistance is skin friction resistance. Micro-bubble has been shown to be able to reduce skin friction. This micro-bubble method gives the possibility to lower the friction without any change in the present hull form of a ship. The application of the micro-bubble technique reduces the surface friction by a variation of the viscosity of the fluid around the ship and makes a modification in the structure of the turbulent boundary layer. However, not much is known about the correct size, quantity, area of coverage which can effectively form a skin friction reducing mechanism. There are many established methods, such as Venturi tube type generator, tangential water-jet and forming of dissolve air and also a chemical process, such as electrolysis, may result in bubble production [1]. The use of micro-bubble as reducing agent of drag can lead to the creation of bubbly mixture near the flow surface that can significantly advances in the understanding of the underlying physical process of drag reduction. The current applications of these techniques to surface ships are discussed.
Autofocus Microscope System using Contrast Measurement Approach
Authors: Ehang Thang , Othman Mohd Afzan , Mahmood Nasrul Humaimi , Abdul Razak Mohd Azhar
Published: September 2015

Cell counting is a method used to quantify cells for disease diagnosis and medical research. Generally, hemocytometer is used to count cells as it is a cheaper and simple method. Specimen contains cells is loaded into the hemocytometer and placed on a microscope. The coarse adjusting knobs of microscope are turned to focus the cells. For a beginner user, to get focused cells is time-consuming. If the user too harsh with the adjusting knob, it may loosen the knob gear. Moreover, if the cells are too over focused, it may cause damage to the objective lens and the hemocytometer. In order to overcome these problems, an autofocus system is developed to control the movement of adjusting knob in achieving the focused image automatically. A CCD camera is attached to the microscope to capture images of cells via gigabit Ethernet. The images are then analyzed using contrast measurement method. To control the movement of knob, an attachable stepper motor is used. The movement is stopped when the focused image is achieved. As a result, the autofocus system could assist a user to focus cells faster and make the microscope become more user-friendly.
Review of Brain Lesion Detection and Classification using Neuroimaging Analysis Techniques
Authors: Mohd Saad Norhashimah , Syed Abu Bakar Syed Abdul Rahman , Muda Ahmad Sobri , Mohd Mokji Musa
Published: September 2015

Neuroimaging plays an important role in the diagnosis brain lesions such as tumors, strokes and infections. Within this context, magnetic resonance diffusion-weighted imaging (DWI) is clinically recommended in the differential diagnosis of several brain lesions by providing detailed information regarding lesion based on the diffusion of water molecules. Conventionally, the differential diagnosis of brain lesions is performed visually by professional neuroradiologists during a highly subjective, time-consuming process. In response, computer-aided detection/diagnosis (CAD) has become a major topic of research and, in light of novel image processing techniques, has become a widespread, possibly indispensable tool for accurate diagnosis and reduce the time required. The objective of this review is to show the recent published techniques and state-of-the-art neuroimaging techniques for the human brain lesions. The review covers neuroimaging modalities, magnetic resonance imaging, DWI and analysis techniques for CAD in detecting and classifying of brain lesion.
ASIC Design of Natural Frequency of ECG Signal for Atrial Fibrillation Detection Module using High-Level Synthesis Approach
Authors: Abdul-Kadir Nurul Ashikin , Mat Safri Norlaili , Othman Mohd Afzan
Published: September 2015

The growth of interest in the development of reduced-scale electrocardiogram (ECG) system based on field-programmable gated-array (FPGA) design platform is increasing. This study provides initial result of mapping digital signal processing to hardware design for specific purpose. In this paper, a part of digital signal processing for atrial fibrillation classification was implemented to register-transfer level (RTL) design. The specific part was feature extraction of ECG signal. The algorithm of ECG signal feature extraction was natural frequency from second-order system for detecting atrial fibrillation. By applying high-level synthesis method, three designs were implemented for natural frequency behavior. The designs were two Single-Cycle (Design 1 and Design 2) and Multi-Cycle fully-constraint (Design 3), of which logic utilization consist of 2530, 36 and 1, respectively. Performance evaluation among all designs were compared.
Dielectric Properties of Potassium Hydroxide-Treated Palm Kernel Shell for Microwave-Assisted Adsorbent Preparation
Authors: Ahmad Zaini Muhammad Abbas , Mohd. Noor Aini Nadhirah , Kamaruddin Mohd. Johari , Kok Yeow You , Mohd. Setapar Siti Hamidah
Published: September 2015

This study was aimed to evaluate the dielectric properties of the reactants mixture at varying temperatures and concentrations for microwave-assisted adsorbent preparation, and to study the adsorptive characteristics of the resultant adsorbents. Palm kernel shell (PKS) was used as the precursor while potassium hydroxide (KOH) was employed as the activator. Different concentrations of KOH solution and ratios of KOH:PKS of 0:1, 0.5:1, 1:1, and 2:1 were prepared, and the measurement of the dielectric properties was performed using open-ended coaxial probe method. Results indicate that the relative dielectric constant, εr' is inversely proportional to the frequency, f. The trends of relaxation time, τ and penetration depth, DP with respect to the frequency and temperature were also reported. Adsorbent prepared using a higher ratio of KOH shows a greater removal of methylene blue. Dielectric properties are imperative especially for selecting suitable operating conditions and in designing the applicator for effective preparation of adsorbent.
Extraction and Identification of Vitamin E from Pithecellobium Jiringan Seeds Using Supercritical Carbon Dioxide
Authors: Che Yunus Mohd Azizi , Zhari Salman , Haron Saharudin , Arsad Nur Husnina , Idham Zuhaili , Ruslan Muhammad Syafiq Hazwan
Published: September 2015

Pithecellobium Jiringan (P. Jiringan) is traditionally known as natural herb consists of several medicinal compounds (vitamin E). Supercritical carbon dioxide extraction (SC-CO2) has been proven as potential method to extract interest compound from herbs. By altering pressure and temperature, the specific compound can be extracted. In this study, the SC-CO2 operating conditions are pressure (20.68 MPa to 55.16 MPa) and temperature (40°C to 80°C) in one hour extraction regime was used to extract vitamin E from P. jiringan. The quantification of vitamin E was analysed with Gas Chromatography Time of Flight Mass Spectrometry (GC-TOF-MS). The responses are overall oil yield and vitamin E yield. The overall oil yield was obtained at the highest condition of 55.16 MPa and 80°C with asymptotic yield of 8.06%. In contrast, the highest amount of vitamin E obtained is 0.0458mg/g sample (80.14 ppm) at the lowest extraction condition of 20.68 MPa and 40ᵒC.
Fouling Evaluation for Ultrafiltration of Protein-based Washwater: A Resistance-in-series Model Approach
Authors: Kamarudin Diyana , Ali Nora’aini , Ismail Mahirah , Othman Norasikin
Published: September 2015

A comprehensive understanding of fouling mechanisms throughout the separation system process is crucial in designing a desired bio-separation system. In this research, we have adopted a resistance-in-series model to determine magnitude of four major resistances that govern in fouling mechanisms namely membrane hydraulic (Rm), adsorption (Rad), pore plugging(Rpp) and cake formation (Rc) resistances. The experiments were conducted using a tubular ultrafiltration Polyvinylidene (PVDF) membrane with surimi wash water as model protein-solution. Two main operating parameters of trans-membrane pressure (TMP) and cross-flow velocity (CFV) were chosen to study the effects of operating conditions towards fouling mechanisms evaluated using resistance-in-series model. The resistance magnitudes were in the following sequence: Rpp >Rad > Rc > Rm. The growth kinetics of each phase on resistances and the kinetic constants represent the extent of flux drop were quantified. Permeate obtained from the filtration process produced the clarified washwater with satisfactory quality physically and physico-chemically based water on national water quality standards.
Fractional Freezing of Ethanol and Water Mixture
Authors: Md Zamani Siti Haizum , Yahya Norshafika , Zakaria Zaki Yamani , Jusoh Mazura
Published: September 2015

Fractional freezing was introduced to separate a mixture that contains a volatile organic compound in this case; ethanol and water. The mixture was separated by using freezing process since both ethanol and water have different freezing points. This method is an alternative method for fractional distillation as it does not consume high amount of energy to supply heat for vaporization purpose. Besides, this method is safer to our environment as it does not liberate any harmful vapor or gases since there is no heating process involved. In this study, the performance of the process in producing high purity ethanol was evaluated based on two parameters which are stirring rate and coolant temperature. It was found that the concentration of ethanol in liquid phase increased as the stirring rate increased. The ethanol concentration has increased by 52.2% when the stirring rate was at the highest rotating speed which is 500 rpm. When the coolant temperature was decreased to -14˚C, the ethanol concentration in liquid phase increased the most by 56.5%. Thus it can be concluded that the concentration of ethanol in liquid phase increased as the coolant temperature decreased.
Numerical Prediction Performance of Kraft Lignin Extraction Using Boundary Breakage Model
Authors: Ooi Zing-Yi , Othman Norasikin , Nyuk Yan Chan
Published: September 2015

This study predicts the performance of kraft lignin extraction using emulsion liquid membrane (ELM) from pulping wastewater using boundary breakage model. The model was developed based on the previous study with some modifications and assumptions. Therefore, in developing kraft lignin extraction model, it will consider emulsion globule approach and the emulsion swelling and breakage during the ELMs process.  It was found to be numerically stable and reliable in predicting the behavior of kraft lignin extraction using ELM for long duration of time.  MATLAB software was used to predict the performance of ELM on extracting kraft lignin from pulping wastewater based on the model developed. At optimum condition, the simulation prediction result was found to have a small deviation with the experimental data on extraction efficiency.The model was computed with some parameter effects including initial feed concentrations; treat ratio and agitation speed, which demonstrated that the prediction results were in agreement with the theoretical study of ELM. The data instills confidence in the model as a useful prediction model on kraft lignin removal by ELM process in pulping industry.
Performance of Electrostatic Field in Continuous Demulsification of Simulated Crude Oil Emulsion
Authors: Othman Norasikin , Kah Sin Tan , Mohamed Noah Norul Fatiha , Zing Yi Ooi , Jusoh Norela , Nasruddin Nur Alina
Published: September 2015

Water-in-oil (W/O) emulsion is always formed in crude oil production. In most cases, the presence of water droplets in crude oil is undesirable because they can cause several problems such as corrosion of process equipment and a decrease in crude oil quality, as well as its market price. In this research, a simulated W/O emulsion that consists of kerosene as a continuous oil phase, water as a dispersed phase and SPAN 80 as an emulsifier has been formulated. The feasibility of using Span 80 for W/O emulsion formation and emulsion stability has been investigated. Stability test proved that the emulsions with 2 w/v % of Span 80 were stable and no separation was observed for the first 48 hours of gravitational settling. Besides, this research also aimed to study the effects of several parameters such as frequency, emulsion flow rate, voltage, water content in emulsion, and emulsifier concentration on the demulsification performance under high voltage electric field. The results showed that the best demulsification performance was 90% using electrical method at 1000 Hz of frequency, 10kV of voltage, 0.4 mL/s of emulsion flow rate, 2 w/v % of emulsifier, and 30 % of water portion of simulated crude oil.
FIBER OPTIC DISPLACEMENT SENSOR FOR HONEY PURITY DETECTION USING GLUCOSE ADULTERANT
Authors: Hida N. , Abdullah M. , Yasin M.
Published: September 2015

A fiber optic displacement sensor (FODS) using a transmission technique was developed to determine the purity of honey using glucose adulterant. This was achieved by detecting the output signal of pure honey and adulterated honey with different addition percentage volume of glucose. The honey sample was adulterated with different percentage of glucose ranging from 0-10%. Prior that, the performances of sensor is first demonstrated by sensing output signal without any sample in a quartz cell. The linearity obtained is more than 99% in the range of 0 mm to 2.5 mm and the sensitivity is 32.65 mV/mm. The result from performance of sensor towards pure and adulterated honey showed that the highest sensitivity of all samples was achieved at 10% concentration of adulteration and the lowest sensitivity was obtained at 0% concentration (pure honey). Thus, FODS based on transmission technique has a potential to act as honey purity sensor by detecting the contamination of adulterant substances present in pure honey. The faster, simpler and cheaper devise is a promising technique to be employed in food industrial sector. Fiber optic displacement sensor in detecting honey purity for glucose adulteration.
ALL-OPTICAL HYSTERESIS SWITCHING USING MOBIUS CONFIGURATION MICRORING RESONATOR CIRCUIT
Authors: Noorden Ahmad Fakhrurrazi Ahmad , Mohamad Azam , Bahadoran Mahdi , Chaudhary Kashif , Aziz M. S. , Jalil Muhammad Arif , Ali Jalil , Yupapin Preecha
Published: September 2015

The novel twisted ring resonator called add-drop Mobius microring resonator is introduced and modelled with the analytical solution of transfer matrix methods for the generation of optical bistability. Simulated results show that, the add-drop Mobius configuration provides greater phase shift due to the longer length of propagation per roundtrip than add-drop filter configuration. In add-drop Mobius system, drop port generated the optical bistable hysteresis loop with 19.25 mW output switching power and through port generated lower switching power as 5.55 mW. The drop port of the system is found as the suitable port for the operating the all-optical hysteresis switching.
DUMBBELL SHAPED INLINE MACH–ZEHNDER INTERFEROMETER FOR BIO-CHEMICAL DETECTION
Authors: Lokman A. , Arof H. , Ali N. M. , Harun S. W.
Published: September 2015

A new dumbbell-shaped inline Mach Zehnder interferometer (MZI) is developed using an arcing process of a fusion splicer for measurement of various bio-chemical concentrations in distilled water. The sensor probe consists of two bulges separated by a tapered waist that generates a good reflected interference spectrum. The interference spectrum is red-shifted with the increase in the bio-chemical concentration due to the increment of the refractive index of the surrounding medium, which reduces the phase difference between the core and cladding modes. In sensing the concentration of glucose solution from 0% to 12%, the dip wavelength increases from 1554.419 to 1554.939 nm in a quadratic manner with the coefficient of determination of 0.9818. The sensor has a sensitivity of 0.0354nm/%. The corresponding linearity is 99.05% and the limit of detection is 3.87%. For NaCl solution, the shift in dip-wavelength is linearly proportional to the increase in its concentration. The sensitivity obtained is 0.0329 nm/% with a linearity of more than 99.68%. The limit of detection is 4.32%. Lastly, for uric acid solution, the sensitivity obtained is 0.0006 nm/%. The slope shows a good linearity of more than 99.48% for a 7.52% limit of detection.
PULSE LASER ABLATION IN LIQUID INDUCE GOLD NANOPARTICLE PRODUCTION
Authors: Affandi Syafiq , Bidin Noriah
Published: September 2015

Over recent years, there has been an explosive growth of interest in the development of novel gel-phase materials based on small molecules. It has been recognized that an effective gelator should possess functional groups that interact with each other via temporal associative forces. This process leads to the formation of supramolecular polymer-like structures, which then aggregate further, hence gelating the solvent. Supramolecular interactions between building blocks that enable gel formation include hydrogen bonds, interactions, solvatophobic effects and van der Waals forces.
SHADOWGRAPHY OF SHOCK WAVE INDUCED BY DOUBLE PULSE TECHNIQUE
Authors: Nugroho Waskito , Khamsan N. E. , Abdullah M. , Ganesan K.
Published: September 2015

High-speed videography based on double pulse of Nd:YAG laser to capture dynamic expansion of shock wave is reported. A Q-switched Nd:YAG laser was employed  as an input signal and disturbance source. Nitrodye laser was utilized as a flash. The shock wave generation was recorded via CCD video camera. Synchronization is organized associated with a digital delay generator. Nd:YAG laser was focused to generate an optical breakdown in distilled water. Double pulses were generated within the interval of one second. The first pulse of Nd:YAG laser was used to trigger the dye laser and the second pulse to generate shock wave. Manipulation of delay times allow to freeze the dynamic expansion of shock wave. The double pulse technique is appropriated for laser system with the absence of external trigger unit. Lack of electronic failure is the advantage offer by the double pulse technique.
TRAPPING OF GOLD NANOPARTICLE AND POLYSTYRENE BEADS BY DYNAMIC OPTICAL TWEEZERS
Authors: Aziz M. S. , Tufail K. , Khamsan N. E. , Affandi S. , Daud S. , Bahadoran M. , Ali J.
Published: September 2015

Gold nanoparticles and polystyrene beads are very important to use in advanced nanoscopic optical trapping techniques to probe any biological system of interest. Multiple trapping of these particles with different diameters can be performed by an optical tweezers system employing dark soliton controlled by Gaussian pulse within a particular configuration of microring resonators. By controlling some parameters and input power of the system, dynamics of the tweezers can be tuned. Radiation pressure acting on the particles including gradient and scattering forces were theoretically measured as a function of normalized position from the center of the laser beam. In this work, the highest output signal in the form of potential well is recorded at 112.80 W corresponding to 1.6 mm wavelength. Sizes of the tweezers are found within the range of 20 nm and the highest value of the optical force is recorded at 895.70 pN. We have demonstrated that the gradient force component is dominant over particle size within Rayleigh regime, thus a good agreement with theory is found.
DATA ASSOCIATION OF RF-VSLAM FOR OCEAN OBSERVATION USING BLIMP
Authors: Abdul Kadir Herdawatie , Arshad M. R.
Published: September 2015

This paper describes a selection of features for potential landmarks for ocean observation system using radio frequency visual simultaneous localization and mapping (RF-VSLAM) framework. Due to dynamic changes of the ocean surface caused by the ocean gyres, the features selection is difficult. Therefore, the tendency for vehicles to drift is high. As a solution, we introduced the beacons as an anchor node as an aid to correct the navigation and improve data association. We investigated the data association stage of the RF-VSLAM system which improved the state estimator for the aerial vehicle. The goal is to produce a correct association to the landmarks, since wrong data association will produce inaccurate maps. The points features were extracted from a monocular camera using SIFT as detector and descriptor. The experimental data of the dynamic changes of water surface has been evaluated. The result showed that the data association method was able to produce correct and accurate landmarks selection.
BACKSTEPPING CONTROL STRATEGY FOR AN UNDERACTUATED X4-AUV
Authors: Md. Zain Zainah , Harun Nur Fadzillah
Published: September 2015

A nonlinear control method is considered for stabilizing all attitudes and positions (x, y or z) of an underactuated X4-AUV with four thrusters and six degrees-of-freedom (DOFs), in which the positions are stabilized according to the Lyapunov stability theory and angles are stabilized using backstepping control method. A dynamical model is first derived, and then a sequential nonlinear control strategy is implemented for the X4-AUV, composed of translational and rotational subsystems. A controller for the translational subsystem stabilizes one position out of x-, y-, and z-coordinates, whereas controllers for the rotational subsystems generate the desired roll, pitch and yaw angles. Thus, the rotational controllers stabilize all the attitudes of the X4-AUV at a desired (x-, y- or z-) position of the vehicle. Some numerical simulations are conducted to demonstrate the effectiveness of the proposed controllers.
THE PERFORMANCE OF DIRECTIONAL FLOODING ROUTING PROTOCOL FOR UNDERWATER SENSOR NETWORKS
Authors: Idrus Nur Asfarina , Abdullah Jiwa
Published: September 2015

The specific characteristic of underwater environment introduces new challenges for the networking protocols. Underwater Wireless Sensor Networks (UWSN) and terrestrial Wireless Sensor Networks (WSN) share some common properties but their differences necessitate specialized new protocols for successful underwater communication. In this paper, a specialized protocol, known as Directional Flooding Routing Protocol is being chosen as the protocol to implement the routing mechanism for underwater sensor networks (UWSNs). The protocol is analyzed and evaluated. Simulation experiments have been carried out to find the suitability of various protocols for the sub aquatic transmission medium, whether in freshwater or seawater. The goal of this paper is to produce simulation results that would illustrate the performances of the protocol for a given metric such as end-to-end delay, packet delivery ratio and energy consumption. By analyzing the simulation results, DFR is considerably reliable for UWSN because this protocol is suitable for the sub aquatic transmission medium such as seawater.
EXPERIMENTAL ANALYSIS OF HOMEOSTATIC-INSPIRED MOTION CONTROLLER FOR A HYBRID-DRIVEN AUTONOMOUS UNDERWATER GLIDER
Authors: Isa Khalid , Arshad M. R.
Published: September 2015

This paper presents a homeostatic controller algorithm and its performance, which controls motion of a hybrid-driven underwater glider. The homeostatic controller is inspired from a biological process known as homeostasis, which maintains a stable state in the face of massively dynamics conditions. The objective is to obtain a better control performance of the glider motion control system with a presence of disturbance, which is the water current. The algorithm was simulated by using MatlabTM. According to the simulation results, in order to achieve the desired pitch angle, the homeostatic controller was able to optimize the glider’s ballast mass and distance of the glider’s sliding mass by reducing the ballast mass up to 17.7% and shortening the sliding mass distance up to 53.7% when compared with the linear-quadratic regulator (LQR) and model predictive control (MPC). Furthermore, validation analyses of the homeostatic controller performance between the simulation and experimental results have shown very satisfactory performance.
INTRODUCTION TO OPERATIONS OF A HIGH-RESOLUTION ACOUSTIC CAMERA ON CRABSTER CR200 AND APPLICATIONS
Authors: Park JIn-Yeong , Baek Hyuk , Shim Hyungwon , Jun Bong-Huan , Lee Pan-Mook
Published: September 2015

This paper describes operations of a high-resolution multi-beam acoustic camera installed on Crabster200 (shortened to CR200) and application researches. The CR200 is a new type of ROVs having six artificial legs driven by BLDC motors. The robot thrusts itself using the legs on seafloor and controls its body posture and attitude. Each leg has four degrees of freedom. And the robot is supposed to inspect and work in fast current flow and turbid water where visibility is very low. The name of “Crabster” came from a combination of crab and lobster because the CR200 imitates behaviors of the two creatures to keep its position against water current flow. In turbid water, performance of typical optical cameras is limited and fails. Therefore, in this case, the acoustic camera can be a good alternative to image objects of interest using acoustic beams. The CR200 is equipped with high-resolution acoustic camera using 3M Hz frequency obtaining maximum 2.9 mm resolution with a rotation which provides two degrees of freedom; roll motion and pitch motion. Yaw motion cannot be provided by the rotator. Then, the CR200 have to rotate its body in place to obtain yaw motion. From these roll motion, pitch motion and yaw motion with image processing, we extract and derive depth perception, 3-dimensional reconstruction and mosaicking, respectively. In this paper, we introduce practical uses of the acoustic camera in offshore and water basin and its application researches. The authors have tried to verify the performance of CR200 as an actively adaptable underwater mobile observant platform.
SIMULATING UNDERWATER DEPTH ENVIRONMENT CONDITION USING LIGHTING SYSTEM DESIGN
Authors: Mohd Aras Mohd Shahrieel , Abdul Azis Fadilah , Syed Abdul Hamid Syed Mohamad Shazali , Edwend Daswir Saiful , Ali Fara Ashikin
Published: September 2015

The major obstacle faced by the underwater environment system is the extreme loss of color and contrast when submerged to any significant depth whereby the image quality produced is low. The studies can be easily done by developing the prototype that may imitate the underwater environment. In order to develop the prototype, suitable lighting system are used where it act as an imitator for underwater environment with different depth. Next the color option that use for the imitator prototype should be suitable for underwater lighting system. By using both suitable lighting system and color option for the system, this prototype might be able to produce image that can be comparable with the actual environment. The water tank is the best choice as the medium for imitating and it’s attached with the red curtain in order to create the environment without any unwanted lighting source. The underwater flood light is use for the lighting system and creates the scenery of the lighting underwater environment. The brightness of the light can be adjustable by adjusting the input voltage. In order to capture and record the image of the imitated underwater, the underwater camera and recordable receiver display is used. Lastly, since the underwater environment has noise the automatic pump is applied to create the ambient noise. The result shows that the appropriate combination of color and the brightness based on different depth it may produce the precise hue and saturation with the actual environment system.
COMPARISON OF DEPTH CONTROL FORM SURFACE AND BOTTOM SET POINT OF AN UNMANNED UNDERWATER REMOTELY OPERATED VEHICLE USING PID CONTROLLER
Authors: Mohd Aras Mohd Shahrieel , Wee Teck Lim , Abdul Azis Fadilah , Mohd Nor Arfah Syahida , Hasim Norhaslinda
Published: September 2015

This paper investigates the depth control of an Unmanned Underwater Remotely Operated Vehicle (ROV) based on ballast tank system using conventional PID controller. The PID Controller is applied to control the depth of the ROV from two different reference points, from the surface and from the seafloor. The concept of ballast tank system selected is piston tank type. Two different sensors are selected, which is pressure sensor for measurement from the surface, and sonar sensor for measurement from the bottom. Control method from both references point are investigated and compared to find out which feedback reference points are more appropriate in different conditions. The implementation phase will be verified through MATLAB Simulink platform.  The verified algorithms will then be tested on the actual prototype ROV. And also the prospect of automated the vertical movement of a ROV.
HISTORY OF DEVELOPMENT OF SQUID-LIKE BIOMIMETIC UNDERWATER ROBOTS WITH UNDULATING SIDE FINS
Authors: Mahbubar Rahman Md. , Wan Nik W. B. , Toda Yasuyuki
Published: September 2015

The underwater robot is a basic tool to explore the unknown territories in the underwater region of the coastal areas and oceans, both from the scientific and industrial perspectives. With the aim of developing an efficient and environmentally friendly underwater robot, a Squid-like robot with two undulating side fins has been developing for many years by the authors' group in Osaka University, Japan. The high ambitious project started in 2002; from then different models have been developed to reach the goal of achieving a high-performance underwater vehicle. The body and propulsion system of the robot have been developed by following the swimming mechanism of flat-fishes that use undulating side fins, e.g. Squid, Stingray Cuttlefish and Manta. The Squid-robot is now in its fifth generation of development. In the present paper, the review of the development of models of the Squid-robot is presented. The development of the mechanical system and the control system of each model is described in brief. Some CFD computations and motion simulations of Model-4 are also discussed. The background of developing a new model and the updated features are stated for each model respectively. The future target of development of the robot is also pointed out. The objective of this paper is to provide relevant and useful information to the engineers involved in underwater vehicle design, and for those with an interest in the fast-growing area of biomimetic swimming robots.
LEAP MOTION UNDERWATER ROBOTIC ARM CONTROL
Authors: Jun Wei Lee , Wei Sen Loi , Md. Sani Zamani
Published: September 2015

The robotic arm structure and control algorithm are designed for a purpose, to pick and place an object task at underwater which is attached to a ROV (Remotely Operated Underwater Vehicle). It is controlled by an innovated gesture control system, Leap Motion controller. The arm structure of pick and place is controlled by Arduino as microcontroller to control the angles and displacements of the servomotor precisely. The detection of position and orientation of the fingers and hands processed by develop control algorithm in Javascript language and sent to the Arduino. Meanwhile, a detailed 3D drawing is drawn precisely by using SolidWorks for the fabrication. After the platform is completed, kinematic and inverse kinematic equations and calculations are programed into JavaScript language for the control algorithm. Lastly, the hardware and software combined all together. With developed control algorithm, the robotic arm mimics human’s fingers and arm movements which more user friendly interface especially underwater scavenging and salvaging. Since it designed for underwater, the accuracy and precision are crucial for robotic arms, it undergo several experiments and tests for investigate reliability performance of developed robotic arm.
POSITION CONTROL OF SINGLE LINK UNDERWATER ROBOT MANIPULATOR
Authors: Hj Shukor Ahmad Zaki , Miskon Muhammad Fahmi , Ali @ Ibrahim Fariz , Md Nor Muhammad Khairi
Published: September 2015

This paper presents the responses of underwater manipulator control using conventional PID controller. Underwater manipulation tasks are difficult due to the presence of water as its environment. Many underwater vehicles invented incorporate underwater manipulators which could be used for underwater rescue, recovery or operations such as welding or ship repair. It is desired to investigate the position response of underwater manipulator using conventional PID control without modelling the dynamics which includes motion in water. For this purpose, a single link manipulator was experimented and compared between the response of the manipulator underwater and the manipulator without water to compare accuracy of the position tracking. Two different reference trajectories were given, namely step and varying frequency position control.
DESIGN PLANNING OF A RAILWAY NETWORK SYSTEM: USING A SIMULATION MODEL
Authors: Adham Ali , Younis Mohamed
Published: September 2015

Railways are one of the most popular means of mass transportation systems. The proposed approach has a universal characteristic that can be applied by cities or authorities to design a strategic plan of urban transportation systems that can solve advanced transportation problems. This study focused on designing a new railway network between two big cities in Malaysia—Kuala Lumpur and Kuantan. The simulation model applied for planning the new railway design and analysis is an important factor. The overall objective of this approach is to increase the advantages of passenger service and public transportation systems as well as to make available other transportation means between these two cities. In addition, the model will also choose the best railway network that can accommodate more passengers along the routes between these two cities.
DETERMINING ALTERNATIVES FOR METAL FORMING LUBRICANTS: A STUDY USING PLANE STRAIN COLD EXTRUSION PROCESS OF JIS-A1100 PURE ALUMINUM BILLET
Authors: Nurul M. A. , Syahrullail S. , Musa M. N.
Published: September 2015

Lubrication is very important in metal forming processes to control wear and friction at the interface between interacting surfaces. Non-renewable resources, such as plain mineral oils are widely used due to its ability to act as a supplier to wearing contacts; it may function as a film material or even sustain chemical transformations to become a film material. Since non-renewable resources can only last for more than a decade, renewable resources have been studied in order to find alternative lubricants that can present similar results in terms of extrusion load and product quality. Two renewable lubricants were analyzed (RBD palm olein and jatropha) together with an additive free paraffinic mineral oil, VG32, which acted as a reference lubricant. The experiment used a cold work plane strain extrusion apparatus that consists of a pair of taper die and a symmetrical work piece (billet). The billet material was made of annealed pure aluminum JIS-A1100 with radius of 5 mm in the deformation area. It was found that higher viscosity lubricants produced low extrusion load and friction during metal forming process with no major severe wear on product quality. Based on the results, it was proven that renewable resource based lubricants can be considered as a substitute for common lubricants used in the industry, since they present similar results with those currently applied in the industry.
POTENTIAL OF OIL PALM FROND LIQUID EXTRACT AND FIBER AS FEEDSTOCK FOR BIO-BUTANOL PRODUCTION
Authors: Aliyu Abubakar Sadiq , Abdul Aziz Azhar , Yahya Adibah , Abdul Lattiff Zulkanain
Published: September 2015

Oil palm frond is the most abundant yet untapped biomass in Malaysia. The objectives of the present work are to study the influence of the age of oil palms on productive sugar yield from oil palm frond extracts and to highlight the potential OPF liquid extract and fibers as feedstock for biobutanol production. Oil palm tree age between 5-10, 10-15 and 15-25 years were sampled for the study. The analysis was conducted using DNS method. The findings indicated that OPF petiole with the age limit of 15- 25years gives higher glucose concentration of 40.50g/L as compared with 17.85g/L of 5-10 years.  Furthermore, the percentage carbon content of 41.04% and 37.45% obtained from the elemental analysis conducted using various micro elemental analyzers, indicated the suitability of OPF as a promising feedstock for biobutanol production.
A REVIEW ON THE FABRICATION TECHNIQUES OF ALUMINIUM MATRIX NANOCOMPOSITES
Authors: Marini C. D. , Fatchurrohman N.
Published: September 2015

In recent years, metal matrix composites have been considered as materials that offer better mechanical properties compared to conventional alloys. Recently, the developments of metal matrix nanocomposites (MMNCs) have become more attractive in various applications. However, the synthesis of MMNCs by conventional casting method has shown a limitation due to low wettability of the reinforcement phase by the molten metal. This paper is aimed at reviewing the best result techniques to fabricate the aluminium matrix nanocomposite (AlMNCs). However, each of these techniques has their own advantages and disadvantages. This review concludes powder metallurgy (PM) as the best technique for mass production and cost effectiveness.
MODIFICATION OF RBD PALM KERNEL AND RBD PALM STEARIN OIL WITH ZDDP ADDITIVE ADDITION
Authors: Farhanah A. N. , Syahrullail S. , Musa M. N. , Bahak M. Z.
Published: September 2015

Vegetable oils have gained worldwide concern due to environmental issues since it is biodegradable, renewable and environmental-friendly. However, the limitations of vegetable oils such as having low oxidation stability and poor low temperature properties need to be solved. The purpose of this paper is to evaluate the tribological behavior of refined, bleached and deodorized (RBD) palm kernel and RBD palm stearin by using a modified pin-on-disc tester. The influence of an anti-wear/extreme pressure (AW/EP) additive on the anti-friction and anti-wear characteristics was also evaluated. The experiment was carried out by varying zinc-dialkyl-dithiophosphate (ZDDP) additive concentration of 1wt%, 3wt% and 5wt%; load of 1kg, sliding speed of 2.5 m/s, test duration of 60 minutes and at room temperature. The findings have revealed that without an additive, RBD palm kernel and RBD palm stearin have high friction coefficient and wear as compared with synthetic oils. The addition of additives helps in the improvement of tribological performance of tested vegetable oils. It can be concluded that vegetable oils have a great potential to be used as a petroleum-based substitute.
QUALITY IMPROVEMENTS & INCREASE IN ELECTRICITY GENERATION THROUGH ANAEROBIC DIGESTION IN RURAL AREAS; A FEASIBILITY REPORT
Authors: Rafique Muhammad Zeeshan , Ab Rahman Mohd Nizam , Saibani Nizaroyani , Arsad Norhana , Khan Khatak Bakhtawar , Ghauri Muhammad Farroq
Published: September 2015

Availability of electricity is one of the basic necessities in rural areas. In an energy-deprived country, there is a need for new and workable development of good quality energy generation systems to meet the economic demands because of population increase. Most of the rural areas are facing wastage control and dumping issues because of this increase in population. Furthermore, the rural areas are also facing severe energy crises of electricity unavailability or low voltages. Anaerobic Digestion is basically a practical technology that does not only resolve the issue of waste disposal, but is also helpful in producing energy through these wastes. The major focus of this research work is the provision of a feasibility report that will aid in the introduction of anaerobic digesters in rural areas to minimize the electricity burden. With proper use of anaerobic digesters, quality energy can be made available for domestic use, thereby contributing an overall decrease in the amount of load-shedding experienced by rural people.
FABRICATION OF PYRAMIDAL CAVITY STRUCTURE WITH MICRON-SIZED TIP USING ANISOTROPIC KOH ETCHING OF SILICON (100)
Authors: Abidin Ummikalsom , Majlis Burhanuddin Yeop , Yunas Jumril
Published: September 2015

Microelectromechanical System (MEMS) are systems of micron-sized structures and typically integrated with microelectronic components. Bulk micromachining using wet anisotropic etching is able to etch silicon substrates to a desired three-dimensional (3D) structure, depending on the silicon crystallographic orientation. To date, MEMS components i.e. thermal, pressure, mechanical, bio/chemical sensors have been fabricated with wet anisotropic etching of silicon. This paper presents the fabrication of a 3D pyramidal cavity structure with micron-sized tip of silicon (100) using anisotropic KOH etching of w/w 45 % at 80 oC temperature. Volume percent of 10 % IPA as a less polar diluent is added to the KOH etching solution in saturating the solution and controlling the etching selectivity and rate. Smooth etched silicon surface of hillock free is able to be achieved with IPA addition to the KOH etching solution. A characteristic V-shaped cavity with side angle of 54.8 degrees has successfully been formed and is almost identical to the theoretical structure model. Comparison of two different silicon nitride window masks on the micron-size tip formation is also investigated. Under etch, over etch and etching selectivity, as common problems effecting the micron-tip size variation, are also addressed in this work. In conclusion, anisotropic KOH etching as a simple, fast and inexpensive bulk micromachining technique, in fabricating 3D MEMS structure using silicon (100), is validated in this work.
RIVERBANK FILTRATION: EVALUATION OF HYDRAULIC PROPERTIES AND RIVERBANK FILTERED WATER AT JENDERAM HILIR, SELANGOR
Authors: Ghazali Miskiah Fadzilah , Adlan Mohd Nordin , Abd Rashid Nur Aziemah
Published: September 2015

Riverbank filtration (RBF) is a natural process where river water is induced to flow through riverbed soils to pumping wells located on the banks. It is a well-established and proven natural water treatment technology. Improvement of water quality is achieved by a series of chemical, biological and physical processes during subsurface passage. This paper aims at evaluating the hydraulic properties of the aquifer and bank filtered water at the RBF study area located in Kg. Jenderam Hilir, Selangor. The pumping well was able to produce 142.21 m3/hour of water with a drawdown of 2.17 m. Transmissivity (T) and hydraulic conductivity (K) were 59.15 m2/hour and 4.41 m/hour respectively. Turbidity and color from the range of 52.1 to 62.3 NTU and 9 to 44 PtCo were reduced to 0.27 to 0.55 NTU and 7 to 12 PtCo respectively.