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Kenyataan Akhbar Kementerian Kesihatan Malaysia : Situasi semasa jangkitan penyakit Coronavirus 2019 (Covid-19) di Malaysia, 1 Februari 2022
No full textThis item is made available on Ministry of Health Malaysia, Covid-19 homepage at http://covid-19.moh.gov.my
Multiple objective optimization using artificial bee colony algorithm for optimal placement and sizing of distributed generation
No full textMaster of Science in Electrical System EngineeringThe implementation of DG may lead to several problems in power system. The increase in system losses and unwanted voltage levels outside the allowed electricity utility limits may cause by DG if the power injected by DG units is in an inappropriate place. The costs of network may increase and give the undesired outcomes. In addition, the reverse power flows may introduce and the generation protective system may be interrupted. The main aim of this research is to investigate the optimal placement and sizing of single and multiple DGs in distribution system using multi-objective method. Thus, this research presents a multi-objective performance index based on the size and location of distributed generation (DG) in power system to counter the problems. The placement and sizing of DG are selected optimally by technique of optimization. The technique of artificial bee colony
algorithm (ABC) has been studied to solve these multi-objectives problems which are real
power loss, reactive power loss, short circuit current, and voltage profile. The algorithm
used is then tested on standard IEEE 69 bus distribution system. The validation results of
the effectiveness of the ABC method are presented and proven through the comparison
with other methods of optimization which is Particle Swarm Optimization (PSO). This
includes the multi-objectives problems that have significant impact in choosing the
optimum sizing and location of DG, which was represented in term of multi-objective
index. The overall value of multi-objective index that is significantly different with
different number of DGs install into the system is identified. The reliability aspect of power
distribution systems is found to be improved. Finally, number of DGs installation that will
reduce the number of multi-objective index (IMO), and also will reduce other problem in
power system is identified
LMMSE-based low complexity image denoising in non-uniform directional filter bank
No full textMaster of Science in Computer EngineeringThis dissertation is about creating a non-redundant, effective and low-complexity denoising method. Denoising an image involves removing noise from an image to keep the original elements of the image and remove unwanted additions. Transform-based
denoising depends on the transform used in the denoising method. Recent works focus on improving the performance of the denoising, ignoring the complexity. This work studies the complexity of well-known transforms that capture texture in images
sufficiently, known as Contourlet transform (CT) and non-uniform directional filter bank (NUDFB). Complex wavelet transform (CWT), CT and non-subsampled Contourlet transform are examples of the base of denoising methods in the majority of current work. All these transforms perform well but they are complex and involve redundancy. Noise applied to images in this work is Gaussian noise and all images used are greyscale; the Linear Minimum Mean Square Error (LMMSE) method was used for denoising, with NUDFB as the base transform. The method decomposes the image using NUDFB then recognizes the coefficients to the step of denoising. LMMSE compares the coefficients in different resolutions to predict and remove noise. For measuring work accuracy, Peak Signal to Noise Ratio (PSNR) and Structural Similarity (SSIM) are used. The resulting
images from the proposed denoising method show improvement. The PSNR of the proposed method is higher than thresholding using NUDFB, about 1db. When comparing the proposed method with wavelet transform thresholding and CT, it has higher values than in CT and WT, especially in a high noise ratio. In images that contain directional information, such as fingerprint images, the proposed method has the highest SSIM. The proposed denoising method creates a way of denoising images using fewer requirements because of the low complexity. LMMSE also perform better than thresholding method
Comparative analysis of DC-DC converters for photovoltaic maximum power point tracking applications
No full textMaster of Science in Electrical Power EngineeringPhotovoltaic can be termed as a method to convert light into electricity at the atomic level, a photovoltaic material exhibits a state known as the photoelectric effect which causes them to absorb photons of light and release electrons. Due to larger demand of clean energy, this has led to the improvement of solar energy power generator device which is known as the solar panel. Solar panel comprises of multiple solar cells that convert sunlight into DC voltage, this output voltage or power is unstable due to several factors such as partial shadow, internal resistance, manufacturer defect and lots more. Therefore, undesirable
factor that affects the output of solar module can be controlled by regulating the power output using maximum power point tracking algorithm. There are several methods for MPPT algorithm. The DC-DC converter is one of the most important electronic devices. Buck converter can be used to step down the output voltage, while the boost converter can be used to step up the output voltage. SEPIC and buck-boost converter can be used to step up or step down the output voltage. The main focus in this project is to compare between the converters in terms of tracking maximum power point MPP independently on the environment conditions. Solar module, SEPIC, buck, boost and buck- boost converter are all developed with MATLAB Simulink using SimPowerSystem Library. The result of this study indicated that, SEPIC converter is the most suitable converter for MPPT algorithm as a DC-DC power controller circuit because the SEPIC converter overcomes two limitations, first is non-operational region that appears in buck and boost converter. Second limitation is negative output voltage that appears for buck-boost converter. Also this work proved that the best converter which can work with high efficiency is SEPIC converter
The effect of filler content and chemical modifications on properties of coconut shell regenerated cellulose biocomposite films
No full textMaster of Science in Materials EngineeringThe coconut shell (CS) regenerated cellulose (RC) biocomposite films were produced with CS and microcrystalline cellulose (MCC) using N.N-dimethylacetamide/lithium chloride by solution casting technique. The effect of CS content and different types of chemical modifications using butyl methacrylate acid (BMA), lactic acid (LA) and acetic acid (AA) on tensile properties, X-ray diffraction, morphology, thermal properties and FTIR were investigated. The addition of CS into the regenerated cellulose matrix increased the tensile strength and modulus of elasticity up to 3 wt% of CS content but reduced at 4 wt% of CS. The elongation at break of CS-RC biocomposite films reduced with increasing CS content up to 3 wt% and increased at 4 wt% of CS. The crystallinity index (CrI) and thermal properties also increased with the incorporation of CS content up to 3 wt% and reduced at 4 wt%. The morphological study of CS-RC biocomposite films exhibited at 3 wt% CS content has better dispersion into the RC matrix. The decomposition at maximum temperature (Tdmax) and residue of CS-RC biocomposite films increased with increasing of CS content. Weight loss at temperature 300 and 600 °C decreased with increment of CS content in RC biocomposite films. The chemical modifications of CS-RC biocomposite films improved crystallinity index, tensile and thermal properties of CS-RC biocomposite films at 3 wt% of CS content. Treated CS-RC biocomposite films with BMA, LA and AA exhibit higher tensile strength, modulus elasticity, crystallinity index and thermal stability compared to the untreated CS-RC biocomposite films. The better interfacial interaction between the CS and RC matrix was supported by SEM study which showed smooth surface on the tensile fracture surface of treated RC biocomposite films. The FTIR spectra of treated CS-RC biocomposite films indicated the formation of esterification reaction between CS and chemical modifying agent. The CS treatment with AA has the highest tensile properties and CrI compared with the treatment with LA and BMA of biocomposite films. However, the better thermal stability of CS-RC biocomposite films was found with CS treated with BMA
Boundary layer flow and heat transfer of a nanofluid over a stretching/ shrinking sheet with suction and slip effect
No full textMaster of Science in Engineering MathematicsIn this thesis, the problem of steady boundary layer flow and heat transfer over a stretching/shrinking surface with the velocity slip boundary condition and suction is considered. The fluid that considered in this study, namely the nanofluid. The study
starts with the formulations of the mathematical models that governed the fluid flow and heat transfer. Next, the governing nonlinear equations in the form of partial differential equations are reduced into ordinary differential equations using an appropriate similarity transformation. The resulting system of ordinary differential equations is then solved numerically using a shooting method by means of the built-in programmme in the MAPLE 12 software. The numerical values of the skin friction coefficient, the local Nusselt number which represents the heat transfer rate at the surface and the local
Sherwood as well as the velocity, temperature and nanoparticles volume fraction
profiles, are obtained for the governing parameter namely slip effect parameter with the
fixed values of suction parameter, stretching/shrinking parameter, the Brownian motion
parameter, thermophoresis parameter, Lewis number and Prandtl number. The
numerical results obtained are presented in the form of tables and graphs. The
comparisons of results with previous studies are made to validate the results obtained. It
is found the flow and heat transfer characteristics are influenced by slip effect
parameter. The skin friction coefficient and the local Nusselt number decrease whereas
the local Sherwood number increases with the increasing of slip effect parameter. The
dual solutions are obtained for a certain range of the parameters involved
Kenyataan Akhbar Kementerian Kesihatan Malaysia : Situasi semasa jangkitan penyakit Coronavirus 2019 (Covid-19) di Malaysia, 8 Februari 2022
No full textThis item is made available on Ministry of Health Malaysia, Covid-19 homepage at http://covid-19.moh.gov.my
Kenyataan Akhbar Kementerian Kesihatan Malaysia : Situasi semasa jangkitan penyakit Coronavirus 2019 (Covid-19) dan bencana banjir di Malaysia 7 Januari 2022
No full textThis item is made available on Ministry of Health Malaysia, Covid-19 homepage at http://covid-19.moh.gov.my
Kenyataan Akhbar Kementerian Kesihatan Malaysia : Situasi semasa jangkitan penyakit Coronavirus 2019 (Covid-19) di Malaysia 4 Mac 2022
No full textThis item is made available on Ministry of Health Malaysia, Covid-19 homepage at http://covid-19.moh.gov.my
Kenyataan Media Kementerian Kesihatan Malaysia : Situasi semasa jangkitan penyakit Coronavirus 2019 (Covid-19) di Malaysia 7 Mac 2022
No full textThis item is made available on Ministry of Health Malaysia, Covid-19 homepage at http://covid-19.moh.gov.my