Skip Navigation LinksVolume : Volume 16 No.1 2007

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study_on_the_magnetic_head_length_of_inductive_coil_sensor_for_stranded_wire_rope_testing.pdfSTUDY ON THE MAGNETIC HEAD LENGTH OF INDUCTIVE COIL SENSOR FOR STRANDED WIRE ROPE TESTING
ABSTRACT : Wire ropes are used widely in industrial applications such as elevators, lift system, cable car system and crane services. Therefore, there is an obvious need to perform tests on the integrity of these wire ropes to avoid any fatal accident due to its internal flaw. Apart from visual inspection, the non destructive test methods are available to check the condition of these wire ropes. Hall sensor and fluxgate sensor are examples of the recent methods for wire rope inspection. In this paper, a combination of two permanent magnets and a search coil are used as inductive coil. This inductive coil is a passive type sensor with a simple structure. Under normal condition, the value of flux linkage is constant. Thus, wire rope sensor will induce a signal when there is any crack occurring along the wire rope. This signal is analyzed based on the rate of change of flux due to time. To obtain a higher signal , the effects of head size of the search coil was studied and discussed in this paper. KEYWORDS: Wire rope, magnetic head length, non destructive testing, flux leakage, noise threshold, S/N ratio. Author: M. Norhisam, N. Wei Shin, H. Noor Hasmiza, N. Mariun, Y. Hirama , H. Wakiwaka3
Year: 2007
harmonics_reduction_using_single_phase_shunt_active_filter.pdfHARMONICS REDUCTION USING SINGLE PHASE SHUNT ACTIVE FILTER 
ABSTRACT : Recently, the utility power quality parameters have become an important issue. One of these parameters is the presence of harmonics in the power network. The proliferation of non linear loads contributes to rious orders of harmonics and serious current distortion in the electrical power . The aim of this work is to minimize the harmonic distortion and improve the power factor of non linear loads by using digital-controlled single phase active filter. The designed single phase active filter is ontrolled by the digital signal processor. Experimental and simulation results confirm the validity of the designed single phase active filter. The results indicated that the signed single phase active filter is able to reduce the total distortion harmonic of supply current due to non linear loads. The designed single phase active filter requires further improvement in the control scheme to meet the requirements of the international standard IEEE 512-1992. KEYWORDS : Active filter, harmonic reduction Author: S.M. Bashi and S.T. Seong
Year: 2007
equilibrium_and_kinetic_studies_of_methylene_blue_adsorption_on_activated_carbon_prepared_from_oil_palm_empty_fruit_bunch.pdfEQUILIBRIUM AND KINETIC STUDIES OF METHYLENE BLUE ADSORPTION ON ACTIVATED CARBON PREPARED FROM OIL PALM EMPTY FRUIT BUNCH
ABSTRACT : Oil palm empty fruit bunch, an abundant agricultural waste product in Malaysia, was used to prepare activated carbon by physiochemical activation method. The pre-treated precursor was first carbonized under inert atmosphere, followed by chemical treatment using potassium hydroxide and physical activation using carbon dioxide. Scanning electron microscopy analysis showed that the activated carbon was porous with well developed pores. Adsorption isotherm of methylene blue onto the activated carbon was determined by batch tests at 30°C with initial concentrations of methylene blue ranging from 50 to 500 mg/I. Equilibrium data were fitted to Langmuir, Freundlich, Temkin and Dubinin-Radushkevich isotherm models. The equilibrium data were best represented by the Langmuir isotherm model, with maximum monolayer adsorption capacity of 303.03 mg/g. The kinetic data were analyzed using pseudo-first-order, pseudo-secondorder and intraparticle diffusion models . The pseudo-second-order kinetic model was the best applicable model to describe the adsorption kinetics, giving the lowest sum of squared errors of 4 .77%, with kinetic constants of 0.002-2.624 g/mg h . The adsorption performance of the empty fruit bunch-based activated carbon on methylene blue was comparable to commercially available activated carbon. KEYWORDS : Adsorption, empty palm fruit bunch, activated carbon, methylene blue, Langmuir isotherm, pseudo-second-order kinetic model. Author: I. A. W. Tan, A. L. Ahmad and B. H. Hameed
Year: 2007
effect_of_opefb_on_mechanical_properties_and_processibility_of_cpe-impact_modified_pvc_u_composites.pdfEFFECT OF OPEFB ON MECHANICAL PROPERTIES AND PROCESSIBILITY OF CPE-IMPACT MODIFIED PVC-U COMPOSITES
ABSTRACT : The effect of OPEFB fillers on the mechanical properties and processibility of CPE-impact modified PVC -U composites were investigated. The poly (vinyl chloride) (PVC) resin, chlorinated polyethylene (CPE), oil palm empty fruit bunch (OPEFB) filler and other additives were first dry-blended using a laboratory blender before being sheeted w ith a two-roll mill. Test specimens were then hot pressed, after which the mechanical properties were determined. The processibility studies of the dry-blends were carried out using a Brabender Torque Rheometer. The results showed that the flexural modulus improved while impact and flexural strength of OPEFB-filled composites decreased with the addition of OPEFB. The fusion time of the CPE-impact modified OPEFB-filled unplasticised poly (vinyl chloride) (PVC-U) composites decreased upon the addition of 10 and 20 phr of OPEFB but increased drastically on further increase to 30 and 40 phr. KEYWORDS : PVC-U, CPE, OPEFB filler, impact strength, flexural properties, fusion time. Author: Aznizam Abu Bakar, Azman Hassan and Ahmad Fuad Mohd Yusof
Year: 2007
effect_of_force_stages_approach_for_sensor_less_linear_dc_motor_positioning_system.pdfEFFECT OF FORCE STAGES APPROACH FOR SENSOR LESS LINEAR DC MOTOR POSITIONING SYSTEM
ABSTRACT : Linear motor has gained popularity as linear motion drive in industry and factory automation. These developments were encouraged by the advantages offered by linear motors such as flexibility in size and design, and deliver high performance for applications requiring linear motion. However, the main constraint for system designer to consider linear motors in their application is the cost for every complete package of linear motor. Generally, linear motors are more expensive than its counterparts due to the sensory technologies used for positioning system. For typical linear motor driver, a positioning sensor is usually attached to the motor which provide feedback positioning signal to the controller. For some applications, where positioning is not too critical such as robot end gripper, the high precision and expensive positioning sensor is not necessary. Removing this sensor from the system reduce the overall system cost. This research propose a sensor less positioning system for linear DC motor (LDM). The ideas to control the position of the LDM are by controlling the current supplied to the motor by using manipulating technique of Pulse Width Modulation (PWM) signal. A few variant patterns of PWM signal are used to drive the motor which is single stage, dual stage, triple stage and quadruple stage. The variant patterns of PWM signal were created by combining multiple values of duty cycle running in a single PWM signal. A mathematical model for constructed LDM has been derived based on damped force oscillation of mass spring system theory. The equation of motion for LDM is then simulated using Matlab software. The time response of the system based on simulation results has been studied and proper adjustment to control parameters has been made to improve the rise time, overshoot percentage and steady state error. KEYWORDS : Linear DC Motor, PWM signal, duty cycle, single stage, dual stage, triple stage, quadruple stage Author: M. Norhisam, H. Ezril, F. Azhar, S.M Bashi and H. Wakiwaka
Year: 2007
asean_cooperation_in_the_field_of_non_conventional_energy.pdfASEAN COOPERATION IN THE FIELD OF NON-CONVENTIONAL ENERGY
ABSTRACT : The ASEAN region has a population of more than 500 million people within its 10 member countries. Since its formation 38 years ago, significant changes and improvements have been seen, particularly in the field of science and technology. Chronologically, commencing in 1971 the Committee on Science and Technology (COST) was first established with the purpose to promote and intensify cooperation in science and technological activities and to raise the level of technological and scientific advancement of member countries. In 1989 a newly revised plan of action was adopted to promote economic development and help achieve a high quality of life for the people of ASEAN. Subsequently at the Roundtable of Technology Scan in Bali in August 1997, ASEAN technology scan mechanism was created with the purpose of a collaborative mechanism for collection, evaluation, transfer and development of science and technology opportunities for the benefit of ASEAN. Nine sub-committees were formed to coordinate and plan actions. These nine fields are considered to have great influence in the 21st century, one of which is the Non-Conventional Energy Research (SCNCER). SCNCER has developed a number of projects namely the EC-ASEAN Cogeneration Programme Phase Ill and Regional workshops on drying technology. These projects have been implemented within the region with the objective to develop, increase and improve the socio-economic status of ASEAN. Therefore this paper highlights the success of these projects which in turn stresses the importance of ASEAN cooperation. KEYWORDS : ASEAN cooperation, SCNCER, cogeneration, drying technology. Author: Ir. Mohamad Fadzil bin Adnan @ Nan
Year: 2007