Radzai Said

Effect of Reprocessing Palm Fiber Composite on the Mechanical Properties

Concern for the environment, both in terms of limiting the use of finite resources and the need to manage waste disposal, has led to increasing pressure to recycle materials at the end of their useful life. This work describes the effects of reprocessing on the mechanical properties of oil palm fiber reinforced polypropylene composites (PFC). Composites, containing 30wt% fiber with 3wt% Maleate Polypropylene as a coupling agent, were reprocessed up to six times. For this composite, tensile strength (TS) and Young modulus (YM) were found to decrease by 9.6% and 4.7% after being reprocessed for six times. Flexural strength was found to decrease by 23.8% with increased number of reprocessing. The hardness numbers of the composite were found to increase by 7.43% from 72.10 to 77.89 after the sixth reprocessing. In general the degradation on the mechanical properties is considered to be small and PFC has potential to be reprocessed.

Analysis of the Biceps Brachii Muscle by Varying the Arm Movement Level and Load Resistance Band

Biceps brachii muscle illness is one of the common physical disabilities that requires rehabilitation exercises in order to build up the strength of the muscle after surgery. It is also important to monitor the condition of the muscle during the rehabilitation exercise through electromyography (EMG) signals. The purpose of this study was to analyse and investigate the selection of the best mother wavelet (MWT) function and depth of the decomposition level in the wavelet denoising EMG signals through the discrete wavelet transform (DWT) method at each decomposition level. In this experimental work, six healthy subjects comprised of males and females (26 ± 3.0 years and BMI of 22 ± 2.0) were selected as a reference for persons with the illness. The experiment was conducted for three sets of resistance band loads, namely, 5 kg, 9 kg, and 16 kg, as a force during the biceps brachii muscle contraction. Each subject was required to perform three levels of the arm angle positions (30°, 90°, and 150°) for each set of resistance band load. The experimental results showed that the Daubechies5 (db5) was the most appropriate DWT method together with a 6-level decomposition with a soft heursure threshold for the biceps brachii EMG signal analysis.

Optimization of Fluidised Bed Granulation Process Parameters for Urea Granule Manufacturing Using the Response Surface Method

Fluidised bed technology is commonly applied in the pharmaceutical, agricultural and food production technology. The aim of this work is to identify the optimum process parameters in order to gain the best hardness and density values for the urea granules from the fluidised bed granulation. The layout of the experiments are based on Central Composite Design of Response Surface Method. The analyzed data shown that the optimize value for each of these parameter are 0.10MPa, 32.11Hz, 50% w/w, 42.250C for spray pressure, fan speed, urea solution concentration and inlet air temperature with 1.71 kgf/granule hardness and 1.85 g/cm3 density were predicted. Experimentally, using the predicted optimize input parameter, the hardness and density observed were 0.20 kgf/granule and 1.30 g/cm3 respectively.

The Effect of Mesh Size And Frictional Force on Simulation of Aluminium Honeycomb Under Quasi-Static Loading

This paper focuses on the works to model the aluminium honeycomb with the effect of meshing size that implemented into a shell body of the honeycomb and frictional force that introduced into an interaction between the honeycomb and rigid plates. The model is performed by using ABAQUS 6.12 in the explicit environment. The honeycomb with 0.0127 m cell size is modelled and three types of mesh size which are 3 mm, 1 mm and 0.8 mm are analysed based on buckling mode and load-displacement characteristics. No friction coefficient is applied during simulation. From this simulation, 1 mm meshing size is the optimize value where the load-compression pattern graph is almost similar like the experimental result compared with others meshing size. But the buckling mode is slightly different compared with the experimental result where the bottom part of honeycomb made the contract or negative expand behaviour. In order to avoid this behaviour, the friction coefficient is introduced between the honeycomb surface and rigid plates surface. Two values of friction coefficient are tested which are 0.1 and 0.3. The findings is the frictional coefficient 0.3 and meshing size 1 mm are optimized values that can avoid the contract behaviour and the result of buckling mode is similar with the experimental result.

Top Spray Fluidized Bed Granulated Paddy Urea Fertilizer

Top spray granulation process is a common technique used widely in pharmaceutical, food and special chemical modification for fertilizer manufacturing. Nevertheless, there is still a lack of studies regarding to the description of controlled parameters with dynamic correlation in targeting to produce urea granules. Thus, this research was carried out to introduce the crucial applied process parameters using top spray technique for paddy urea fertilizer production.The acquisition process parameter readings were verified by obtained yield of urea granules (UG) which featured as an optimum particle diameter size from 2 mm to 6 mm with reasonable hardness (crush strength) in range 2.0 kg/granule to 4.0 kg/granule, these criteria were required as a slow - release mechanism during soil adsorption interaction in paddy field to reduce amount of fertilizer consumption. Three significant parameters have been selected namely as air inlet temperature, the viscosity of binder solution and rate of top spraying from starch liquid binder to generate greater UG size from wet granulation interaction with smooth coalescence and consolidation growth . The data classification was screened by One-Factor-at-a-Time (OFAT) 101 method and supported by 2 levels and 3 factors (23 ) of full factorial design for clear description to vindicate the critical parameter required during urea granulation using fluidized bed granulator corresponds to low energy consumption and economical process. The obtained parameter readings and findings of UG features were useful to be applied further for detail investigation on next stage regarding to agglomeration profile and mechanism using CCD camera and PDA monitoring devices.

An Experimental on Honeycomb Core in the Axial Direction under the Quasi-Static Loading

This paper focuses on the quasi-static response of the aluminum honeycomb core based on an experimental work. The load-compression and energy absorb characteristics of the out-of-plane aluminium honeycomb core are studied for three varieties of the core cell sizes which are 0.01905, 0.0127 and 0.00635 m. The crushing tests were conducted on the Instron machine with a displacement control of 5 mm/min. The initial part in the load-displacement graph shows linear elastic characteristic, followed by a non-linear elastic-plastic regime before it collapses. Based on the observation, the cell sized 0.01905 m shows the global buckling collapse, but the cell sized 0.0127 and 0.00635 m collapse as progressive buckling mode. The cell size 0.00635 m shows highest energy absorption due to it has the highest density and it collapses like the progressive buckling mode compared with the others specimen.

Simulation on Force Tracking Control of a Magnetorheological Damper under Impact Loading

This paper focuses on the design of the control structure which consists of inner loop controller employed for MR damper under impact loading by using computer simulation. The simulation is done by using MATLAB 7.0. The structure of the inner loop control for the proposed MR damper model uses a simple PI control to achieve the desired force. In this simulation, the MR damper model that has been validated with the experimental result is used to simulate the actual force that produced by MR damper. The performance of inner loop controller to track the actual force produced by MR damper by obtaining the several input functions which are half wave of sinusoidal, saw-tooth, square and random functions of desired force with the variation in pendulum mass of 15 kg and 20 kg are investigated. It can be seen clearly that under several input functions, the proposed polynomial model with PI controller has the good ability to track the desired damping force under impact loading.

Validate of Local Exhaust Ventilation (LEV) Performance through Analytical, Experimental and Computational Fluid Dynamic (CFD): A Case Study Model

Local Exhaust Ventilation (LEV) system are a tools in engineering control stated in Occupational safety and health management system where to protect a workers from inhale the contaminant that will effected to their breathing system. To design, construct and applications of LEV are followed an international guidance such as American Conference of Governmental Industrial Hygienist (ACGIH).A sample two inlet and outlet of LEV system are design based on ACGIH including hood, ducting branch, main ducting, elbow, y-tee, fan and stack. The design is based on ACGIH standard with assuming the contaminant are fumes with 2 inlet of 6 inches round duct and outlet is 8 inches round type. The result from calculation according to the size of branch duct size, main duct size, fan capacity and stack size. Other data contribute are velocity and pressure drop along the duct.LEV system are design by using Solid Work Software and export file to Ansys 14.0, where the simulation are used to compare the result of velocity and differentials of pressure before proceeds to construct the system as additional in design process as follow in ACGIH Standard. Finally result of this study indicated that no significant different of the result of velocity along the ducting between design, experimental and compare with the simulation results.Where the analysis shows different compare with analytical almost below 30% and further study on comparative different of static pressure should carry out.

V-Bend Die Forming Performance of Oil Palm Fiber Composite

Composite materials have steadily gained recognition worldwide for its uses in various sectors such as aerospace, infrastructures and automotive industries. In stamp forming of V-bend die, the most sensitive feature is elastic recovery during unloading called spring-back. This phenomenon will affect bend angle and bend curvature. This research studies the effects of tool radius, feed rate, temperature and weight ratio of fiber to Polypropylene on the spring-back of palm fiber composite. Analyzed results obtained from Design of Experiment (DOE) shows temperature, fiber composition followed by feed rate gives significant effect towards spring-back. The suggested temperature, fiber composition and feed rate to get the smallest spring-back angle in the current study are 150°C, 30wt% and 500mm/min.

Usage of Magnetorheological Damper in Active Front Bumper System for Frontal Impact Protection

In this paper, the effectiveness of the active bumper system to reduce the jerk of a vehicle during collision is discussed. The mathematical model is done by using MATLAB 7.0 to simulate a collision between a pendulum and a vehicle installed with the active bumper system. In the active bumper system, it consists of three parts which are magnetorheological(MR) model, inner controller and outer loop controller. The validated model is used to develop an inner loop controller by implementing a close-loop PI control to track the desired damping force through simulation. The governing equations of motions of vehicle collision and MR damper model are then integrated with the well known control strategy namely skyhook control. The performance of skyhook control is then compared with the vehicle with passive damper and common vehicle by using computer simulation in order to reduce the acceleration and the jerk of the vehicle during collision.