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The study of chemical modifications on the properties of soy protein isolate (SPI) / kapok husk (KH) biocomposite films for agriculture applications
No full textDoctor of Philosophy in Materials EngineeringIn this research, the utilization of kapok husk (KH) as a filler in soy protein isolate (SPI) was studied to replace the plastic and petroleum based polymer films for packaging. The effect of KH loading, crosslinking agents such as phthalic anhydride (PA), adipic acid (AA) and formaldehyde (FA), and chemical modification of KH with 2-ethylhexyl acrylate (EA), methyl methacrylate (MMA) and sodium dodecyl sulphate (SDS) on tensile properties, morphology, thermogravimetry analysis (TGA), moisture content, total soluble matter, gel fraction and enzymatic biodegradation properties of SPI/KH biocomposite films was studied. Glycerol was used as a plasticizer to give flexibility to the biocomposite films. The experimental results showed that the increases of KH loading have increased the tensile strength, modulus of elasticity, and gel fraction of control SPI/KH biocomposite films, whereas the elongation at break, char residue, moisture content, total soluble matter and weight loss of enzymatic biodegradation decreased. The morphology of tensile fracture surface of control SPI/KH biocomposite films at higher
KH loading showed better interaction between KH filler and SPI matrix. The addition of
different crosslinking agents such as PA, AA and FA had increased the tensile strength
and modulus of elasticity of crosslinked biocomposite films. The gel fraction of all
crosslinked biocomposites films higher than uncrosslinked biocomposite films. However,
crosslinked biocomposites exhibited decrement in elongation at break except AA, char
residue, moisture content, total soluble matter, and weight loss of enzymatic
biodegradation than uncrosslinked biocomposite films. The SEM studies of crosslinked
SPI/KH biocomposite films with PA, AA and FA indicated the rough surface, due to the
enhanced crosslinking. The FTIR spectra of all crosslinked biocomposite films illustrated
the changes in functional group. The treated KH with EA, MMA, and SDS biocomposite
films have higher tensile strength and modulus of elasticity in comparison with untreated
SPI/KH biocomposite films. Nevertheless the elongation at break, char residue from
TGA, moisture content, total soluble matter and weight loss of enzymatic biodegradation
reduced. All treated SPI/KH biocomposite films performed slight changes in gel fraction
as KH loading increased. The treated KH with EA, MMA and SDS had enhanced the
interfacial bonding between KH and SPI matrix in biocomposite films, which were
proved by SEM analysis. It can be summarized that incorporation of KH in SPI film has
the ability to improve the properties of SPI/KH biocomposite films. However in
comparison, SPI/KH biocomposite films treated with EA could give the highest
improvement in all characterization
Design of microcontroller based dual braking mechanism for micro-wind turbine
No full textMaster of Science in Electrical Power EngineeringThe work proposes dual braking mechanism. It consisted of dynamic braking and yaw control. Both mechanism is used to provide safety to the micro-wind turbine. It protects from over speed and also functioning as speed regulator. A conventional braking system for micro wind turbine uses passive braking system. The limited wind speed range is an issue when to deal with the passive braking system. Therefore, the goal of this study is to extend the range of operation of micro wind turbine and
preventing it from over speed condition. The Proportional Integral Derivatives (PID) algorithm is used to control the braking mechanism based on Integral Time Absolute Error (ITAE) criteria to determine its coefficient. The proposed mechanism able to
maintain rotational speed under the maximum limit when wind speed increase from 4.8-5.2 m/s without the needs to shutdown operation
Design and implementation of embedded tracking system using spatial parallelism on FPGA for robotics
No full textMaster of Science in Embedded System Design EngineeringThe robot tracking system is one type of utilization system on a mobile robot and generally utilized as a part of numerous perspectives, for example, security or military. In this project, an active and passive robot tracking system used FPGA platform was implemented. The robot can identify and track objects by using Infrared (IR) and thermal sensors. Perception
approach and motion planning is the most essential part in this project .Two long range IR sensors utilized for the tracking process to distinguish any moving object and two contactless temperature sensor (TMP007) for detected the temperature objects while a ultrasonic sensor as the obstacle avoidance sensor . The project platform was the DE0-Nano board and the
characteristic of FPGA offer programmability and makes it easier to implement on different
mobile robot platforms. Sensors and robot platform was integrated with the DE0-Nano board.
A structure VHDL coding was used for design the robot tracking system and Quartus II
13.0sp1 as a development CAD tool. The implementation of complex tracking system with
FPGA platform (DE0-Nano) was possible because of the rich logic elements, a specific
sensors characteristics testing and robot stability was carried out to master those sensors and
robot. The result for this project was shown the frequency for DE0-nano achieved up to 1.3
GHz, also the total logic elements were used for this project is 8,045 and shown the output
reading voltage of the IR sensor is high reflectivity for the white colour object compared to
another colours like blue and black, also the detection distance for contactless sensor was
15cm. Hence, using the FPGA technology improved the performance of implemented system
Study of the effect surface treatment of Kenaf fiber on mechanical and water absorption of kenaf filled unsaturated polyester composite
No full textMaster of Science in Polymer EngineeringIn this research, unsaturated polyester/kenaf fiber (UP/KF) composites was prepared by using hand lay-up process. The effect of surface treatment of kenaf fiber on mechanical, morphology, chemical structure and water absorption of kenaf filled unsaturated polyester composites were studied. Different concentrations of stearic acid (SA) were applied, i.e. 0, 0.4, and 0.8 wt%. The Fourier transform infrared (FT-IR) spectra of kenaf fiber shows high intensity of the peak around 3300-3400 cm-1, which is attributed to the hydrogen bonded OH stretching. However, the treated kenaf fiber with stearic acid shows the elimination of OH
group and this peak is vanished. This is due to the reaction of (-COOH) group of stearic with (-OH) group of kenaf fiber. Tensile strength of treated kenaf fiber/ unsaturated polyester composites was found to be higher for 40 wt% loading of kenaf fiber. The highest tensile strength value was obtained after treatment with 0.4 wt% concentration of stearic acid at 56 MPa and tensile modulus was at 2409 MPa. From the flexural strength result obtained, it is clearly seen that 40 wt% loading of kenaf fiber and treatment with 0.4 wt% concentration of stearic acid give the highest value at 72 MPa and flexural modulus at 3929 MPa. Scanning Electron Microscope (SEM) observation revealed that the surface of kenaf fiber after treatment with SA became rougher. Moreover, the treatment of kenaf fiber with stearic acid gives better fiber to matrix interaction of kenaf fiber inside the polymeric matrix. The results of water absorption study revealed that increasing the loading of KF in the composite will
result is increasing the tendency to absorb water. However, the absorption was significantly decreased after treatment with stearic acid as well as the time to reach to the equilibrium state
Development of new model for multiwavelet-based OFDM over wireless channel and its implementation in FPGA
No full textDoctor of Philosophy in Communication EngineeringOrthogonal Frequency-Division Multiplexing (OFDM) has been widely utilized in the field of high speed communication systems, due to its prominent features. However, it is prone to impairments such as Inter-Symbol Interference (ISI), Inter-Carrier
Interference (ICI), and high Peak-to-Average Power Ratio (PAPR). Moreover, the Guard Interval (GI), which is inserted between the OFDM symbols, will take up nearly 25% of the bandwidth, decreasing the data rate and increasing the system‟s complexity.
To mitigate for these impairments, a new OFDM based on Discrete Multiwavelet Critical-Sampling Transform (OFDM-DMWCST) model (Model 1) has been proposed in this work. The theoretical analysis proved that the OFDM-DMWCST model has
higher bandwidth efficiency and less computational complexity compared to other OFDM systems utilizing Discrete Multiwavelet Over-Sampling Transform (DMWOST), Discrete Wavelet Transform (DWT), and Fast Fourier Transform (FFT).
The simulation results showed that the OFDM-DMWCST provides better Bit Error Rate (BER) performance among all OFDM systems over different channel models, namely, Additive White Gaussian Noise (AWGN), flat fading, and frequency-selective fading. For instance, in the frequency-selective fading channel with 4-QAM mapping, at BER = 10-3, the OFDM-DMWCST reported a 1.5 dB and 14.2 dB gain in Signal-to-Noise Ratio (SNR) over OFDM based on DWT and OFDM based on FFT, respectively, while the OFDM based on DMWOST failed to realize such a BER value. Also, the OFDMDMWCST model can realize better PAPR reduction compared to the traditional OFDM model. Moreover, a hybrid technique, consisting of FFT and Sliding Window (SW) algorithm, has been proposed for the development of a new model for OFDMDMWCST and render it more suitable for outdoor applications
Experimental and numerical investigation of hydrothermal effect on mechanical properties of adhesively bonded T-joint
No full textMaster of Science in Mechanical EngineeringThe moisture environment is a significant problem in designing the adhesive joint in any application. Urea fluidisation bed was washed with hot condense water thus created moisture environmental factor. This situation was cited as a problem in designing
adhesively bonded T-joint referring joint part in urea fluidization bed. The purpose of this study was to examine hydrothermal effect on adhesively bonded T- joints with different adhesive thickness in hot water test at temperatures of 80°C, 90°C and 100°C. Two environmental conditions were studied, namely room temperature and dry (RTD) and elevated water temperature (EWT) at 80°C, 90°C and 100°C immersed for 15 minutes. Various bond thickness involved in testing namely 0.5mm, 1.0mm, 1.5mm and 2.0mm. Moreover, the moisture dependence of joint strength was evaluated by comparing those properties with the values at room temperature. Uniaxial loading was performed using a compression test of bulk specimen for both RTD and EWT condition. Another series of tests was run involving T-joint specimen with tensile loading for different adhesive thickness. Finally, the performance of the T-joint application in experiment was compared with the geometrical modelling of T-joint in ANSYS 14.0 software finite element analysis (FEA). Moreover, failure stress was determined as a criteria to investigate the adhesive performance. Results were presented for the best adhesive thickness and moisture environment for Araldite epoxy adhesive. Direct presence of moisture at the adhesive interface alters the interfacial integrity of the adhesive joint. However, the strength of test T-joint specimen immersed in 80°C of hot water and bond thickness 1.5mm appeared to have high strength compared with T-joint specimen at RTD. Moreover, the compressive strength also showed similar behaviour of reductions under
the hot water condition. Furthermore, the approach to predict an experimental result using the commercialised finite element software, the ANSYS 14.0 resulted in a good agreement of similar pattern of failure stress curves. The simulation model has been
predicted, thus can be used to simulate the T-joint and adhesives at numerous boundary conditions
Modeling of power response of photovoltaic model using pertubation-observation and incremental conductance methods
No full textMaster of Science in Electrical System EngineeringSince the search of the energy source considered as one of the main problems in this era, then it will be still one of the most important concerns of the countries. The renewable energy became one of the faster-growing trends in industrial societies since it becomes used for solving shortfall problem in the energy source. In the meantime, the sun is responsible for almost all the energy available on the earth. Photovoltaic systems, which gets the energy from the sun and convert it to electrical energy is one of the best solutions to solve the shortage problems. In this system, there is one point called Maximum Power Point (MPP) representing the maximum output power that can be generated from the system, but the system will be disturbed by changing the environment factors like
irradiance and temperature. Therefore, the changing of environment factors will effect on
the value of MPP, and make the system back to a maximum value by using the tracking
methods. It is called Maximum Power Point Tracking Method (MPPT). There are many
methods in this field with a different performance because this variation leads to
confusion in the selection of the suitable Maximum Power Point Tracking Methods. This
research has reviewed many types of tracking methods and classified them according to
the accuracy, tracking speed, and complexity, by considering the Perturbation and
Observation (PO) and Incremental Conductance (IC) methods being as the most
commonly methods in order to choose the most suitable maximum tracking method to be
applied in Malaysia. The modeling technique has been made and tested to compare
between these two methods. This model uses the irradiation and temperature as inputs
parameters to give a performance indication between the variations of output power with
respect to time. MATLAB have been used in this research. The result shows better time
response and smooths performance while applying Incremental Conductance (IC) method
than Perturbation and Observation (PO) for Malaysia. Towards completion of this project,
the project aimed to create a comparative model, for the two selected methods. The
project other aims included adding the time response and stability factors while testing
the two methods using the models based on the inputs from different states in Malaysia.
When using the model for Malaysian data and taking the average irradiance and
temperature for the two proposed methods, it is recommended to use the INC method,
which shows faster response and better stability