In this paper, the problem of steady laminar boundary layer flow of an incompressible viscous fluid over a moving thin needle is considered. The governing boundary layer equations were first transformed into non-dimensional forms. These non-dimensional equations were then transformed into similarity equations using the similarity variables, which were solved numerically using an implicit finite-difference scheme known as the Keller-box method. The solutions were obtained for a blunt-nosed needle. Numerical computations were carried out for various values of the dimensionless parameters of the problem which included the Prandtl number Pr and the parameter a representing the needle size. It was found that the heat transfer characteristics were significantly
influenced by these parameters. However, the Prandtl number had no effect on the flow characteristics due to the decoupled boundary layer equations.
Konjac glucomannan (KGM) was treated with or without sonication and/or hydrochloric acid (HCl).
Hydrolysis effects on KGM were studied for properties such as degree of hydrolysis, fluidity, molecular mass, and creep properties. The degree of hydrolysis for sonicated KGM and acid treated KGM were not significantly different. However, the combination treatment of acid hydrolysis and sonication was found effective in yielding a smaller molecular weight fraction of KGM and solution with higher fluidity. From the creep analysis, KGM treated with combination treatment exhibited the highest compliance among samples tested. In general, ultrasound mediated acid hydrolysis was found to be a promising technique in degrading high molecular weight biopolymer. This could be attributed to a localized high temperature and high shear forces generated during cavitation that facilitated the endothermic acid hydrolysis.
The agricultural industry scenario in many industrialized countries has adopted an image processing system as a solution to automate the grading process in order to provide accurate, reliable, consistent and quantitative information in addition to the large volumes, which human graders are not able to perform. In Malaysia, the grading of palm oil Fresh Fruit Bunches (FFB) is still performed manually through visual inspection using the surface color as the main quality attribute. It is the intention here to introduce an automated grading system for palm oil FFB using a computer assisted photogrammetric methodology which correlate the surface color of fruit bunches, not the fruitlets, to their ripeness and eventually sorts the fruit to two predefined fruit categories. The methodology consists of five main phases, i.e. image acquisition, image pre-processing, image segmentation, calculation of color Digital Numbers (DN) (data manipulation) and finally the classification of ripeness. This computerized photogrammetric image processing technique using MATLAB® package which is integrated to a sorting system differs in various aspects from other digital imaging technique or machine vision system adopted for classifying fruit ripeness. A comprehensive discussion will be presented based on the results achieved through actual fruit testing on the prototype grading system. The main concern was to ensure the reliability of the computerized photogrammetric technique achievable and the system’s mechanism working as intended. The fruit classification ability of the system yields above 90% accuracy and taking not more than 25 seconds to classify and sort each fruit.
In this present study, a series of polymer electrolyte thin films were synthesized by incorporating different ratios of lithium triflate (LiCF3SO3) in a low molecular weight polyvinyl chloride (PVC) matrix by the solution casting technique. The incorporation of LiCF3SO3 suppressed the high degree of crystallinity in PVC enabling the system to possess an appreciable ionic conductivity. The ionic conductivity of the samples, with different LiCF3SO3 content, was determined by the aid of ac impedance spectroscopy. The highest ionic conductivity of 4.04 10–9 S cm–1 was identified for the composition of PVC: LiCF3SO3 (75:25). Further understanding of the ionic conductivity mechanism was based on temperature-dependent conductivity data which obeyed Arrhenius theory, indicating that the ionic conductivity enhancement was thermally assisted. The possible dipole-dipole interaction between the chemical constituents was confirmed with changes in cage peak, analysed using Fourier transform infrared spectroscopy.
Layered double hydroxide (LDH) with Mg/Al molar ratio of 4/1 (MAN-4) was synthesized by co-precipitation and followed by hydrothermal method. The compound was allowed to undergo ion exchange with K2HPO4 for 48 hours to produce MgAlHPO4 (MAHP-4). The solid produced was characterized using X-ray diffraction (XRD) and Fourier Transform Infrared spectroscopy (FTIR). Adsorption of copper solution by MAHP-4 was carried out using batch experiment by mixing the copper solution and the sorbent MAHP-4. The effects of
various parameters such as contact time, pH, adsorbent dosage and initial concentration were investigated. The optimum pH for copper removal was found to be 4 and the optimum time of copper removal was found at 4 hours. The isotherm data was analysed using model isotherm Langmuir with the correlation coefficient of 0.999 was recorded. The maximum adsorption capacity, Qo (mg/g) of 142.8 mg/g was also recorded from the Langmuir isotherm. The remaining copper solution was determined by using EDXRF (Energy Dispersive XRay Fluorescence spectrometry) model MiniPal 4 (PAN analytical). The results in this study indicate that MAHP-4 has potential as an effective adsorbent for removing copper from aqueous solution.
Melaleuca cajuputi and Acacia auriculiformis trees are major sources of nectar and pollen for Apis dorsata and the colonies are a major source of honey to the rural poor, honey hunters. Honey is a supplementary income to many of these people (including school children) in the Marang district, Terengganu. In this study, Marang area with 270 square kilometers was chosen as pilot study area in Terengganu state for mapping M. cajuputi and A. auriculiformis as two dominant species in low land secondary forest in Terengganu state.To inventory and produce land use map of Melaleuca forest in Marang area, in this study SPOT-5 satellite image in multispectral mode with 10 meter resolution which is acquired in 2007 as optical satellite was utilized. Most images from optical satellites have some null data from ground because of clouds and shadow of clouds. To solve this problem, Hue, Saturation and value (HSV) and Principal Component Analysis (PCA) were used as fusion techniques to replace null data with microwave data which taken from Radarsat-1 image in C-band with 25 meter resolution image. Accordingly, fusion technique which was used in this research not only was a technique to improve information but also caused the accuracy increasing than land use map by just only SPOT-5 image. Also between two different fusion techniques, PCA shows the better result than HSV as two different fusion techniques.
Normally, topographic map is produced using aerial photogrammetry. The recent development in aerial photogrammetry is the use of large format digital aerial camera for producing topographic map, however, the cost of the camera is too expensive and many mapping organization around the world could not afford to purchase it. In certain application, there is a need to map small area with limited budget. This issue has been solved by using small format camera (i.e. conventional or digital) to produce digital map. This study concentrates on the use of unmanned aerial vehicle (UAV) for producing digital map. UAV has been widely used in military for reconnaissance, planning, combat, and etc. Today, UAV can be used by civilian for reconnaissance, monitoring, mapping, and others. The objectives of this study are to investigate the capability of UAV in producing digital map and assess the accuracy of mapping using UAV. In this study, a light weight fixed wing UAV was used as a platform and a high resolution digital camera was used to acquire aerial digital images of the study area. The aerial digital images were acquired at low altitude. After capturing the aerial digital images, ground control points and check points were established using GPS. Then the aerial digital images were processed using photogrammetric software. The output of the study is a digital map and digital orthophoto. For accuracy assessment, the root mean square error (RMSE) is used. Based on the assessment, the results showed that accuracy of sub-meter can be obtained using the procedure and method used in the study. In conclusion, this study shows that UAV can be used for producing digital map at sub-meter accuracy and it can also be used for diversified applications.
Aluminium (Al) is a low cost, lightweight and corrosion resistant material, which corrodes when exposed to pitting agents. Palm olein exhibits characteristics, which indicate its suitability as a corrosion inhibitor. Tween 20, hexane and diethyl triamine were used as additives to Palm olein to form the inhibitor formulation POT2OHA. The inhibition efficiency (IE) and behaviour of the POT2OHA were determined using potentiodynamic polarization in which Al 6061 samples were immersed in a 1 M HC1 solution at 26, 50 and 70 °C in the presence of different POT2OHA concentrations: 0, 0.03, 0.07, 0.10, 0.13 and 0.17 M The IE increased with increasing POT2OHA concentration, but decreased with increasing temperature. The work presented indicates that POT2OHA is a mixed-type inhibitor capable of inhibiting both corrosive anodic and cathodic reactions. According to the Langmuir isotherm results POT2OHA adsorbs on the A16061 surface through semiphys iosorption and/or semi-chemisorption. The POT2OHA adsorption mechanism on Al 6061 takes through the protonation of micelles by the HC1 solution, whereby protonated micelles in the presence of chloride ions adsorb on both cathodic and anodic surface corrosion sites.
Introduction: The purpose of the present study was to investigate exploratory factor analysis of the
Beck Anxiety Inventory (BAI) and reports its reliability and validity in Malaysia. Method: One thousand
and ninety participants from four different samples (namely students, general population, medical and
psychiatric patients) completed the Malay version of Beck Anxiety Inventory, as well as additional
questionnaires such as Fear Questionnaire, Anxiety Sensitivity Index, Depression Anxiety Stress Scale, and Catastrophic Cognition Questionnaire. Results: Exploratory factor analysis revealed a three factor solution and accounted for 48.01% of the total variance. The three-factor structure appeared to be; subjective anxiety, autonomic, and neurophysiology. The Cronbach alpha coefficients (α) ranged from 0.66 to 0.89 with satisfactory overall alpha value (.91). Evidence was also found acceptable concurrent validity of the BAI-Malay (range between r=.22 to r=.67). Conclusion: This study shows that the BAIMalay is a reliable and valid instrument to measure symptoms of anxiety in the Malay population
and can be used in research and clinical service in Malaysia. However, replication of study by using
confirmatory factor analysis and application of the instrument among anxiety patients worth of further
investigation.
The impact of good assessment in medical education depends on how appropriately the tools measure the clinical performance and how reliable, valid and feasible they are to achieve the logical decision. The traditional methods of clinical examination using long and short cases and orals are often argued for its subjectivity, low reliability and inadequate context specificity. Oral test though comparatively more valid due to its face-to-face questions are considered less reliable for problems of unstandardized questions, inconsistent marking and lack of sufficient testing time. Development of an “objective structured clinical examination” (OSCE) was sought as a solution to these problems. But the fragmented representation of the context in a number of stations in OSCE makes it less authentic for an integrated judgment of performance. Yet another method to thought of, was the workplace-based assessment (WPBA) but it takes a snapshot as a predefined attribute of a more complex integrated assessment such as long case. However due to the problem of feasibility it is less likely that high stakes examination as summative assessment will ever be able to attain workplace-based assessment such as Mini-CEX and DOPS. A TOACS (task oriented assessment of clinical skills) format currently used in high stakes fellowship examination in one of the center and claimed to have more active role for examiners was analyzed and compared with OSCE. Author however, did not find a difference except the difference of acronyms of the two formats. Both have multiple, fragmented static or interactive stations of 5-10 minutes duration with or without examiners, patients or exhibits and a marking scheme comprising of checklist or global rating. In the backdrop of this context a new assessment format named the ‘task integrated objective structured clinical examination” or TIOSCE modified from OSCE is currently developed in School of Medical Sciences (SMS) at USM. However, it is a different version of OSCE in which though the principle concept is the same as that of an OSCE, the continuum of clinical skill’s work up of the same patient’s is followed through to test multiple short attributes of clinical competences. As it retains most of the favorable features, TIOSCE also addresses some of the odds features of OSCE.
Utilization of palm kernel expeller (PKE), a palm oil milling by-product, may be diversified through the exploitation of its protein component. The PKE protein could be effectively extracted using an alkaline
solution and followed by enzymatic hydrolysis to produce PKE protein hydrolysates or crude PKE peptide. The extraction of PKE protein was successfully carried out using an alkaline solution at pH11, at ratio of 1:10 (g/ml), PKE powder to alkaline solution with continuous shaking, 150 rpm, in a water bath operating at 50°C for 30 min. The extracted protein powder (PKEP) had 68.50±3.08% crude protein, 0.54±0.03% fat and 0.73±0.02% ash. The freeze-dried PKEP was re-suspend in particular buffer and hydrolyzed with proteolytic enzymes (Alcalase® 2.4L, Flavourzyme® 500MG, pepsin or trypsin) to obtain PKEP hydrolysate (PKEPH). The effect of enzyme concentration (0, 2, 4, 6, 8 & 10%) and time of hydrolysis (0, 6, 12, 24, 48 h) was studied to determine the most efficient hydrolytic conditions. Results showed that all enzymes tested were capable of hydrolyzing the PKEP and producing hydrolysates with different degree of hydrolysis (DH%). At 8.0% concentration, Alcalase®2.4L hydrolyzed PKEP into the highest DH (75.96%) hydrolysate (PKEPH) after 1h hydrolysis. Although only with 2.0% Alcalase 2.4 L concentration, it was sufficient to produce PKEP hydrolysate of 81.35% DH %, but it required 12 h to hydrolyze the protein. Pepsin was relatively the least efficient protease to hydrolyze the PKEP.
This work aims at optimizing the media constituents for citric acid production from oil palm empty fruit bunches (EFB) as renewable resource using artificial neural networks (ANN) approach. The bioconversion process was done through solid state bioconversion using Aspergillus niger. ANN model was built using MATLAB software. A dataset consists of 20 runs from our previous work was used to develop ANN. The predictive and generalization ability of ANN and the results of RSM were compared. The determination coefficients (R2-value) for ANN and RSM models were 0.997 and 0.985, respectively, indicating the superiority of ANN in capturing the non-linear behavior of the system. Validation process was done and the maximum citric acid production (147.74 g/kg-EFB) was achieved using the optimal solution from ANN which consists of 6.1% sucrose, 9.2% mineral solution and 15.0% inoculum.
Nuclear grade (high-purity) graphite for fuel element and moderator material in Advanced Gas
Cooling Reactors (AGR) displays large scatter in strength and a non-linear stress-strain response from the damage accumulation. These responses can be characterized as quasi-brittle behaviour. Current assessments of fracture in core graphite components are based on the linear elastic approximation and thus represent a major assumption. The quasi-brittle behaviour gives challenge to assess the real nuclear graphite component. The selected test method would help to bridge the gap between microscale to macro-scale in real reactor component. The small scale tests presented here can contribute some statistical data to manifests the failure in real component. The evaluation and choice of different solution design of biaxial test will be discussed in this paper. The ball on-three ball test method was used for assessment test follows by numerous of analytical method. The results shown that biaxial strength of the EY9 grade graphite depends on the method used for evaluation. Some of the analytical methods use to calculate biaxial strength were found not to be valid and therefore should not be used to assess the mechanical properties of nuclear graphite.
α-Mangostin was extracted from the pericarp of the Malaysian local Garcinia mangostana linn., The structure was characterised by Infrared red, UV-Visible and Nuclear Magnetic Resonance spectroscopic data. The fluorescence peak at 500nm in ethanol was not observed in PNIPAM microgel solution. The increase of colloidal size of the gel in the presence of α-mangostin was studied by Dynamic Light Scattering and Transmission Electron Microscope. The size of the particle also increases with increasing temperature up to 45⁰C after which it began to shrink. The TEM micrograph at 45°C showed a uniformly structured pattern of the gel occurs in the range of the lowest solution critical temperature.
The in vitro cytotoxic potential of locally produced dental porcelain was evaluated in this study. The cellular response of human osteoblast and fibroblast cell lines were assessed using MTT assay by incubating with the fluid extract of dental porcelain powder and dental porcelain discs (direct test). Aging process was carried out by submerging the discs into 3% bovine serum albumin (BSA) solution. Tests on extracts showed that dental porcelain was significantly different from the control at a concentration of 250 mg/ml. Direct test showed that dental porcelain after aging was not significantly different from the control with a mean (SD) of 89.2 (13.4)%, whereas, it was significantly different from the control before conditioning of BSA with a mean (SD) of 88.5 (12.1)%. However, the dental porcelain caused mild suppression of succinate dehydrogenase activity (
This paper presents the solution to a calculation of the pH of a very dilute solution of a strong acid or base, taking into account the effect of the hydronium or hydroxyl ions generated from the ionisation of the strong acid or base on the ionisation of water, as a second very weak acid. To be solved successfully, this calculation involves the concepts of conservation of charge, pH and the application of the general solution to a quadratic equation. Such an exercise involves the application of skills in basic numeracy, and can provide a core of understanding that can prepare students for
many different sorts of calculations that represent reallife problems in the medical and biological sciences.A programme is presented in C++ which enables the work of students to be individualised so that each student in a class can work through a slightly different pH calculation, in such a way that a class supervisor can quickly check each student’s result for accuracy. This exercise is presented as a potential means of enabling students to undertake and master similar types of calculations involving simple or more complex equilibria.
The takraw ball is a very unique interwoven ball used in the action game of sepak takraw. The traditional takraw ball is manufactured by conventionally weaving split rattan strips into a spherical basket. Modern takraw balls are manufactured by forming strips of plastics materials into interwoven hoop. These interwoven hoops form 12 pentagon holes and 30 intersections. The purpose of this study is to construct a finite-element (FE) model of a takraw ball in particular for normal impact simulation on flat surfaces under low speed conditions. Two FE models were developed to observe the dynamic behavior including impact forces, contact time, coefficient of restitution and deformation of the ball. The first model consists of a single solid hollow ball with 12 pentagon holes and the second model consists of six center strips and 12 side edge strips of
extrusion hoops to form 12 pentagon holes and 270 cross-sections. The models were also compared with results of experimental impact tests whereby the ball was impacted normal to a rigid plate at three different heights. The ball is described in the FE model as a linear elastic material.
It was found that the FE analysis solution of the ball model was found to be reasonably close with the experimental results. However further improvement need to be done by taking into consideration the nonlinearity of the takraw ball under large deformation as well as at high impact velocity.
In the moving layer of particles with variable concentration, the shear estimation is not directly predictable and there is no existing clear mathematical or empirical formula to achieve this objective. This paper presents a developed approach to estimate the shear forces in a flow having suspended and moving layers of solid particles in liquid flow. The two-layer approach was taken whereby the flow consisting of one upper suspended layer of particles in the liquid, and the bottom layer was the moving bed of particles. In the present work, the method of finding the force acting on the pipe wall by the particles in the layer, termed as the ‘dry force’, was presented using a “pseudo hydrostatic pressure” method. To attain the equation for the dry force, a mathematical approach is taken with the assumptions that the flow is horizontal, two-phase pipe flow (solid in Newtonian liquid), incompressible and it is at steady-state. The analysis was conducted considering various particles densities, various concentrations in the suspended layer and different thicknesses of the moving bed. Changing the concentration in the suspended layer from 0.00001 up to 0.001 didn’t showed significant changes in the dry force evaluation. The dry friction force is increasing with increasing moving bed thickness. The developed mathematical model can be
applicable in solving for the shear force in horizontal solid liquid two-phase flows.
Thermal characterization of sugar palm fibre (SPF), reinforced high impact polystyrene (HIPS)
composites, was studied by means of thermogravimetric analysis. The effects of alkaline treatment and compatibilizing agent on the thermal stability of the composites were evaluated. Alkaline treatment was carried out by soaking the fibres in 4 and 6% of NaOH solution, while treatment with compatibilizing agent was employed by adding 2 and 3% maleic anhydride-graft-polystyrene (MA-g-PS) to the composites. Both the treatments were aimed to improve the mechanical performance of the composites. From the study, the thermal stability of the treated composites was found to be higher than that of untreated composites. It is shown that the incorporation of sugar palm fibre influences the degree of thermal stability of the composites. The treatments on composites also contributed to shifting the peak temperature of degradation of the composites. In other words, there are strong chemical reactions between the components of the treated composites. The thermal stability of the composites, with alkaline treatment and compatibilizing agent, was found to be better as compared to those of the untreated composites.
A biodegradable composite (PLA/KBF blends) was prepared using melt blending technique in a brabender mixer and characterized with FTIR and TGA analyzer. Five percent of triacetin and glycerol contents were used as plasticizers to plasticise PLA matrix. KBF was treated with 4% NaOH solution, while 30 wt% of fibre loading was used constantly for all the composite samples. From the FTIR analysis, the additions of triacetin and glycerol to PLA composites did not produce any significant difference, and there were no chemical changes in both the plasticized PLA with the treated and untreated KBF, respectively. Observation done on the TGA analysis revealed that both plasticizers did improve the thermal stability of the composites, and this might be due to the modification on the fibre surfaces, which further led to the delay in the degradation of the PLA matrix and to significant stabilization effect.