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- PublicationRekabentuk susun atur Makro sel VLSI dengan Hibrid genetik algoritma.(2006-05)Several of the tasks involved in VLSI design process involve optimization. Genetic algorithms have been used as a well-suited technique for selected combination optimization problems. Due to tree- structured genotype representation and hybrid, problem-specific operators, the proposed approach is able to deal with different constraints. The major objectives of this project are chip area minimization and interconnection wire length minimization. The genetic algorithm uses three main types of rules at each step to create the next generation from the current population: Selection rules select the individuals, called parents, which contribute to the population at the next generation. Crossover rules combine two parents to form children for the next generation. Mutation rules apply random changes to individual parents to form children. The problem specific knowledge and existing solution techniques can be used to decide a suitable encoding scheme and its interpretation. We can create genetic operators for the new type of coding and can make use of the domain-based heuristics while applying these genetic operators.
- PublicationEvaluation of mechanical and bioactivity properties of surface modified titanium-molybdenum-iron alloys.(2025-08)High modulus and poor cellular response limit the use of Ti alloys in orthopaedic application, Ti-Mo-Fe alloy was designed using d-orbital design and Molybdenum Equivalent (MoE) methods such that low modulus phase (β-Ti) of Ti is achieved. The research leveraged on polymorphic transformation in Ti and the influence of alloying elements on such transformations in designing low modulus alloys. On the other hand, surface topography-bioactivity property dependence was used as a basis for improving cellular response. Using ingot metallurgy and powder metallurgy as fabrication processes, Ti-(y-x) Mo-xFe (where y=15 and x = 0, 2, 4, 6, 8, and 10) were produced. The choice of these alloying elements (Mo and Fe) was based on established safety and the ability to stabilize β-Ti at room temperature. Properties of the alloys were assessed at various stages with the view to achieving the best combination of properties. Density was assessed to establish atomic interactions. Phases present were also characterized using X-Ray Diffraction (XRD) and Electron Backscattered Diffraction (EBSD) techniques. The phase is predominantly β in IM samples; whereas a transition from high modulus phase (α) to a low modulus phase (β) as a function of Mo and Fe co-additions was seen in PM samples. For instance, the 100% α pure titanium transformed to 46.9% β and 53.1% α by adding 15 % Mo ( Ti15Mo,). Addition of 2% Fe further increased the amount of β phase to 47.7% β in Ti13Mo-2Fe and continued upto 53.4 % β (Ti-5Mo-10Fe). Also, EBSD revealed increasing microstructural uniformity when Fe was added to the alloy(s). Furthermore, compression test, nanoindendation and Vicker’s hardness tests were performed to evaluate the mechanical properties. The modulus decreased from 48.38 GPa (Ti-15Mo) to 41.78GPa (Ti-13Mo-2Fe) but increased to 56.06 GPa at Ti-9Mo-6F and 69.73 GPa at Ti-5Mo-10Fe. Consequently, Ti-13Mo-2Fe alloys were considered for biological studies as they exhibited not only lowest modulus (41.78GPa) but also a combination hardness (269.12 HV) and good strength among all the alloys. To improve bioactivity, the alloys were anodized in ethylene-glycol based electrolyte. This led to an increased surface roughness and wettability as determined through atomic force microscopy and water contact angle measurement respectively. Cell culture study revealed that the alloys (Ti-13Mo-2Fe) are biocompatible and pose no risk to the L929 cell line. The cells were viable and proliferated the more compared to Ti6Al4V alloy. However, cell attachment depend strongly on surface morphology as the cells were only attached to anodized substrates. Going by the reduction of modulus through alloying and enhanced biological response due to anodization induced surface roughness, the challenges of modulus mismatch and poor bonding ability limiting the use of Ti alloys in orthopaedic application may be addressed by considering the Ti-Mo-Fe alloys whose surface has been modified via anodization.
- PublicationRekabentuk satu teknik teraair berasaskan “wavelet” Untuk tujuan pengesahan dan pemulihan imej.(2006-05)The Internet technology and image processing technique have become more and more advance. Since the distribution of multimedia content such as digital images across the internet has become easier, the image may be tampered and published by an illegal user. Thus, it is difficult to determine whether an image is authentic or not. In this dissertation, a watermarking technique for image authentication and recovery isproposed. In this scheme, image-content-related features are first extracted and embedded as a watermark into the wavelet domain of the image. In features extraction process, the image is first divided into non-overlapping and equal-sized block. Then for each block, the average of pixel intensities is calculated and the results will be used as the image features. Then, extracted watermark is used to detect whether the image was tampered or not. If the image has been modified, the watermark will be used to restore the tampered parts. The watermarking scheme can support both color and grayscale images. The experimental results indicated that the proposed algorithm is able to detect tampering on image as well as recovering the tampered parts.
- PublicationFabrication and characterization of si-mo modified aluminide coating on austenitic stainless steel via slurry aluminizing for high temperature application.(2025-12)The demand for advanced surface protection strategies for structural alloys in high-temperature environments has intensified due to increasing applications in energy, petrochemical, marine, and aerospace industries. In this work, the fabrication and characterization of silicon–molybdenum (Si-Mo) modified aluminide coatings on austenitic stainless steel (SS304) were carried out using the slurry aluminizing technique, heat-treated at 750 ℃, 800 ℃, and 850 ℃ for 6, 8, and 10 hours. The study aimed to improve the high-performance and corrosion resistance of conventional aluminide coatings by tailoring phase constitution and diffusion behaviour through dual-element modification. The influence of these parameters on coating microstructure, phase composition, thickness, and growth kinetics was characterized using field emission scanning electron microscope equipped with an energy-dispersive X-ray spectroscopy (FESEM) and X-ray diffraction (XRD) analysis. Mechanical characterization, including microhardness, nanoindentation, and adhesion testing, was conducted to evaluate coating integrity. Corrosion performance was assessed in two environments: a 3.5% NaCl solution at room temperature and a molten salt mixture (60% NaNO₃–40% KNO₃) at 600 ℃ for 100 hours. The results revealed that the modified coatings exhibited continuous, compact, and multilayered structures with clearly defined outer, intermediate, and inner sub-layers. The non-modified Al coating primarily formed Al-rich and Fe-rich intermetallic phases, while the addition of Si impeded the growth of brittle Fe₂Al₅ phases, promoting Fe–Al–Si ternary phases. Molybdenum addition led to the formation of Mo–Al phases, and the combination of Si and Mo resulted in the formation of complex intermetallics such as MoSi₂ and MoAl₀.₆Si₁.₄. The growth kinetics of the coating conformed to a parabolic rate law, confirming the predominance of diffusion-controlled growth. The activation energies of the overall coating thickness FeAl, and Fe3Al were estimated in the ranges as follows: Al coating (53-242) KJ/mol, Si-modified (46-155) KJ/mol, Mo-modified (26360) KJ/mol, and Si-Mo-modified (78-365) KJ/mol. Microhardness measurement values were in the ranges: (313- 1003) HV, (320-1010), (378 – 966) HV, and (413- 1070) HV for Al coating, Si-modified, Mo-modified, and Si-Mo-modified, respectively. The Si-Mo-modified coating has the highest adhesion resistance (283 423) µm2, followed by the Si-modified coating (302-545) µm2, the Al coating (652- 1017) µm2, and the Mo-modified coating (882-1254) µm2. The findings from this research establish that the synergistic addition of Si and Mo in aluminide coatings, when fabricated through slurry aluminizing, provides a cost-effective and reliable approach for extending the service life of austenitic stainless steels in aggressive high temperature environments. The study not only advances the understanding of multi element modification in diffusion coatings but also offers practical insights for designing durable protective layers for industrial applications.
- PublicationReal time PH, conductivity and total dissolved solid (TDS) in the maiganga coal mine using internet of things (IOT) based sensor system.(2025-08)The Nigerian mining industry offers significant economic potential but poses critical environmental challenges, particularly water pollution from acid mine drainage (AMD). Mining activities significantly impact water quality through the release of contaminants such as pH-altering substances, heavy metals, and total dissolved solids (TDS). This study addresses the urgent need for real-time environmental monitoring in mining environments by developing an IoT-based wireless sensor system for continuous measurement of pH, electrical conductivity (EC), and TDS in surface water at the Maiganga Coal Mine. The research integrates hydrogeochemical modeling, structural analysis, and cloud-connected sensing technologies to assess, predict, and mitigate pollution risks. The methodology combined field investigations, geophysical surveys, laboratory analysis, and simulation using ANSYS Fluent. Water samples were collected from key locations within and around the mine and analyzed for physicochemical parameters. Seasonal variations showed range in concentrations of pH (1.5 – 5.5), EC (170–6982 µS/cm) and TDS (83–3491 mg/L) within the mining zone, exceeding baseline levels by up to 200%. Structural mapping identified subsurface features like faults and permeable sandstone layers that facilitate contaminant migration. An IoT-based monitoring system was designed using Arduino Nano, calibrated sensors, and mobile-cloud integration, enabling remote data access and real-time visualization. Validation against laboratory results confirmed high accuracy (>95%) and consistency across multiple sampling campaigns. The findings demonstrate the potential of integrated approaches in managing mining-related pollution. This research contributes a scalable framework for sustainable environmental management in mining-impacted regions, aligning with SDGs related to clean water, health, and responsible resource.
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- ItemDoes Shareholder Concentration Matter In Small And Medium Enterprises (SMES)? Empirical Evidence From SMES In Manufacturing Sector In Northern Corridor Economic Region (NCER).(Universiti Sains Malaysia, 2009-06)Given the important role of SMEs as a growth factor in local economy, ensuring a strong and competitive development for this industry segment has become a key concern in making the Northern Corridor Economic Region (NCER) a success. This study investigates the effects of shareholder concentration, together with financial inputs and outputs on the relative operating efficiency in utilization of financial resource (financial efficiency) for SMEs in manufacturing sector in NCER for the financial year 2007. The financial efficiency is derived from Data Envelopment Analysis (DEA). DEA shows that only 27 SMEs scored 100% efficiency, and they are mostly from Penang and Perak. This study delivers three important findings: first, shareholder concentration does affect the financial efficiency for SMEs involved in manufacturing sector in NCER; second, lower financial inputs and higher financial outputs produce higher financial efficiency SMEs involved in manufacturing sector in NCER; third, the distribution of financial efficiency is not balance across the three states in NCER. The last point is consistent with the Korean case reported in Yang (2006).
- PublicationPredicting occurrence of rainfall using discriminant analysis(2009-04-01)Malaysia has a tropical climate that is consistently hot with high frequent rainfall. Water is one of the most vital natural resources for all life on Earth. So, it is important to quantify it accurately. Rainfall rate is affected by some unpredicted weather conditions such as humidity, air pressure, temperature and wind speed which are liable to change. The relationship between the rainfall rate (dependent variable) to the humidity, temperature, air pressure, and wind speed (independent variables) is analyzed by the method of discriminant analysis using the SPSS 15.0 software. A total of 340 cases for year 2008 were used to develop a model to discriminate among the 2 levels of rainfall rate which is rain or no rain. The aim of this project is to develop a set of discriminating functions to predict the category of the rainfall rate. The usefulness of a discriminant model is based upon its accuracy rate, or ability to predict the categories of the dependent variable. As a conclusion, the discriminant analysis in this study successfully estimates the categories of the rainfall rate. The accuracy is high that is 84.7%. So, the results show that the discriminant analysis can be considered as an effective tool in forecasting the type of rainfall condition.
- PublicationIpo Information Disclosure And Price Stabilisation Action From The Perspective Of Information Asymmetry In Hong Kong Listed Companies(2024-08)The topics of IPO have attracted attentions from scholars for a long time. Among these research topics, price stabilisation, which is an aftermarket action taken by underwriters, is relatively less concentrated by prior studies. Factors which cause the stabilisation done by underwriters are not clear, owing to the barrier resulted from the non-mandatory disclosure of such actions in many countries. Meanwhile, as a compulsory document for IPO issuers, the prospectus contains sufficient information for investors to make decision for IPO investment. Recent studies have focused on the information disclosed in IPO prospectus, such as the text content and textual tone, and its corresponding influence on market performance. Yet, studies which have investigated the relationship between the information disclosure of IPO prospectus and price stabilisation are scarce. This thesis probes into the potential factors of price stabilisation from the theoretical perspective of information asymmetry by examining how the information disclosed in the IPO prospectus can impact the aftermarket stabilising actions using a sample data from 2004 to 2021 in Hong Kong stock market. Specifically, the effects of the information disclosure related to cornerstone investors, Chinese state ownership, as well as the narrative uncertainty contained in the prospectus, are investigated using ordinary least square regression model. This thesis finds that the information related to cornerstone investors is positively correlated with price stabilising actions in the aftermarket.
- PublicationQuantitative mri fibre tractography in leukoaraiosis: Analysis of lesional and non-lesional cerebral white matter(2022)Background: Leukoaraiosis was first described as area of hypodensity on CT imaging and on conventional MRI, it is an appear hyperintense on both T2-weighted and fluid attenuation recovery inversion (FLAIR). Both may represent a variety of different pathologies, only some of which are associated with tissue destruction and neuronal disfunction. Diffusion tensor imaging (DTI) MR imaging was based on movement of water molecules in biology tissue. DT imaging was widely used to study microstructural in brain, musculoskeletal and spinal cord. Any change in tissue will affect the water molecules movement that provide microscopy information regarding the tissue which allow detection of abnormalities in early stage. The distinctive features of DT imaging are fiber tractography which give quantitative and qualitative assesment of the nerve fiber in the brain. This study compares the ADC, FA and Fiber density Index value between leukoaraiosis and normal control subjects using 3T MRI system. Methodology: A retrospective study was conducted in Hospital USM, Kota Bharu for 36month duration. This study involves age-matched 34 healthy subjects and 34 Leukoaraiosis patients. All of them had undergone magnetic resonance imaging (MRI) where images were then post-processed and underwent first level analysis to meet the optimum sequence and DTI parameter. Second level analysis were then performed using tractography software by manually drawed region of interest (ROI) at leukoaraiosis area and to compare the parametric value with normal appearing white matter subjects at the same region. For effective result, age-matched comparison with same area of brain regions were chosen for both control subjects and leukoaraiosis patients. FA, ADC, fiber volume and voxel were generate automatically by the software. Statistical analysis was using paired T-test to compare value of both group. Results: The mean of FA value in control and leukoaraiosis group were 0.393 (±0.039) and 0.333 (±0.058) respectively. The mean of ADC value in control and leukoaraiosis group were 0.782 (±0.036) and 0.823 (±0.068) respectively. The mean of FDI value in control and leukoaraiosis group were 1.341 (±0.310) and 1.062 (±0.240) respectively. The different was statistically significant in FA, ADC and FDI value between two group. Conclusion: This study found that there is a statistically difference mean value of FA, ADC and FDI between leukoaraiosis and normal appearing white matter control subject. The ability of MRI‐based fiber tractography to delineate the white matter fibre pathways of the brain non‐invasively has raised possibilities for clinical applications and offers potential used for early detection of white matter integrity, evaluation of white matter severity and progression in the future.
- ItemPembinaan Dan Kesan Modul Terapi Seni Dalam Pengurusan Kemarahan Remaja(Universiti Sains Malaysia, 2021-04)Kajian ini bertujuan untuk membina Modul Terapi Seni Dalam Pengurusan Kemarahan Remaja (TASMAR) dan mengkaji kesan modul tersebut. Kajian ini juga untuk mengenal pasti kesahan dan kebolehpercayaan modul. Nilai kesahan modul adalah 82.28 peratus manakala nilai alpha cronbach’s bagi kebolehpercayaan modul adalah .96. Sampel dikenal pasti melalui kaedah persampelan bertujuan. Sampel terdiri daripada remaja yang mendapat skor tahap kemarahan 76-100 dalam ujian State-Trait Anger Expression Inventory-2 Child and Adolescent (STAXI-2 C/A). Bagi melihat kesan modul, rekabentuk kajian kuasi eksprimen digunakan dengan gabungan kaedah kuatitatif dan kuanlitatif. Keputusan kuatitatif mendapati terdapat perbezaan yang signifikan kesan modul terhadap kemarahan remaja, nilai t=2.83, df=71, p=0.00 (p<.05). Kesan modul terhadap pengurusan kemarahan remaja berdasarkan jantina menunjukkan perbezaan yang signifikan, nilai t=5.86, df=70, p=.000 (p<.05). Seterusnya, terdapat perbezaan yang signifikan kesan modul terhadap pengurusan kemarahan remaja berdasarkan masa, nilai t6.54, df=71, p=.000 (P>.05). Secara kuantitatif, modul berkesan dalam pengurusan kemarahan terhadap remaja lelaki dan perempuan. Modul juga berkesan secara kualitatif dengan hasil dapatan temu bual yang membentuk tema-tema yang menunjukkan kesan positif modul terhadap remaja iaitu memberi pengetahuan baru, meluahkan kemarahan, menyembuhkan emosi, merubah diri dan memberi motivasi. Impikasi kajian ini, remaja dapat diberikan kemahiran mengatasi kemarahan. Hal ini dapat mengurangkan kesan negatif kemarahan seperti salah laku, jenayah serta masalah kesihatan mental dan fizikal. Kajian ini juga memberi sumbangan ilmu dalam penghasilan modul intervensi kaunseling menggunakan pendekatan terapi seni.