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- PublicationExplaining Eating Disorder Behaviour Among Chinese University Students Using The Extended Theory Of Planned Behaviourexplaining Eating Disorder Behaviour Among Chinese University Students Using The Extended Theory Of Planned Behaviour(2024-09)Adolescents’ unhealthy eating leads to them to adopt certain measures such as a diet, fasting and other behaviours that are likely to reduce body weight. The measures in turns lead to eating disorders and series of complications, such as impaired digestive system function, endocrine disorders, amenorrhea, hypoglycaemia, malnutrition, or physiological damage to various organ systems, and even life-threatening. It will affect the physical and mental health of the young and incurs high medical costs in one's country. In the long term it will be a physical and mental health issue that will increase medical expenses to treat it. Therefore, using the Theory of Planned Behaviour, this study was conducted to identify the factors that influence eating disorders among university students in the province of Gansu, China. Data was analysed using IBM SPSS and PROCESS 4.0 to answer all research questions developed. Results showed that there was significant difference in attitude towards physical activity, subjective norm, perceived behavioural control, body shape, self-esteem, and intention to engage in physical activities. between gender and body mass index (BMI). Gender and BMI also moderate the relationship between intention, body shape, self-esteem, and eating disorder. However, different gender and BMI in different attitudes (AT), subjective norms (SN), perceived behavioural control (PBC), body shape (BS), self-esteem (SE), and intention (IN) scores have significance. Family incomes only have a significant in self-esteem (SE).
- PublicationMulti-layer Radiation Shielding Design For Compact Proton Therapy System Using Monte Carlo Simulation(2024-09)Proton therapy has emerged as a highly effective treatment for various cancers due to its precision in targeting tumor cells while minimizing radiation exposure to surrounding healthy tissues. However, the design of compact proton therapy facilities poses significant challenges, particularly in terms of shielding requirements, cost, and environmental impact. This study aims to develop a novel shielding design for proton therapy systems that complies with regulatory dose limits while reducing the overall cost and footprint by utilizing alternative materials through a multilayer structure model. The research begins with the characterization of natural aggregate and steel slag as potential alternative materials for concrete admixture, then continues with experimental evaluations of radiation attenuation properties using PuBe, LINAC, and CT-Scan as radiation sources. To further develop and optimize the shielding design, the study employed Monte Carlo simulations using the Particle and Heavy Ion Transport code System (PHITS). These simulations facilitated the creation of innovative shielding configurations, incorporating both single-layer and multilayer structures composed of Portland concrete (PC), steel slag concrete (SSC) , iron (Fe), borated polyethylene (BPE), and recycled high-density polyethylene (HDPE). The experiment results demonstrate that steel slag concrete offers superior radiation shielding performance compared to conventional concrete. The PHITS simulation results demonstrate that the material combination model of PC-SSC on the treatment room wall and PC-SSC-Fe-HDPE on the Maze 1 wall is the optimal configuration with ambient dose equivalent rate value ranging from 13 to 773 mSv/year.
- PublicationIntrinsic self-healable and recyclable rubbers based on ionic crosslinked network(2023-08-01)In modern technologies, rubbers play a significant role to serve various main manufacturing industrial products, for instance vehicles tires, damping systems, wearable electronics, safety gears and many more. In order to fabricate a component which offers high toughness, great damping properties, chemical and thermal stability, rubbers need to be chemically crosslinked through vulcanization process. However, vulcanized rubber with permanent covalent crosslinked network cannot be reprocessed, reshaped or recycled. As a result, waste rubber products have become a serious threat towards ecological and environmental systems. This problem has driven towards emerging of a self-healing rubber technology which has the ability to restore the damage and can be recycled and reprocessed at the same time. The work carried out started with investigation of the potential of self-healing non polar natural rubber (NR) based on zinc thiolate ionic network. The Zn2+ is a potential metal ion candidate for formation of reversible ionic network, thus self-healing ability, recyclability and reprocessing ability would be achievable. In the next work stage, carboxylated nitrile butadiene rubber (XNBR) was chosen to investigate self-healing ability for polar rubber. The strategy is to generate massive Zn2+ salt bonding between zinc thiolate and COOH group on XNBR in order to create electrostatic interaction that allow thermo reversible ionic network. For NR, the samples achieved 100% self-recovery within 10 minutes at room temperature. Evidence for reversible metal thiolate ionic networks was provided by Fourier Transform Infra-Red (FTIR) and swelling density. Followed by mechanical performance assessment which include tensile test, tear strength, fatigue lifespan and creep behaviour. As for the recycled and reprocessed assessment, the vulcanised rubber was recycled and reprocessed for few times and the tensile test, scanning electron microscope (SEM) and welding test were evaluated. Interestingly the rubber was able to be reprocessed for three times and recovered its initial mechanical performance up to 60%. For XNBR, the sample achieved 97.87% self-recovery within 10 minutes at 150ºC. Evidence for thermo reversible ionic network was provided by FTIR and swelling density assessment. Followed by mechanical performance assessment which include tensile test, tear strength, fatigue lifespan and creep behaviour. As for recycle and reprocessing assessment, the results showed that XNBR were able to be reprocessed for three times with significant mechanical performance recovery up to 70%. From the work carried in this research, it was found that NR self-healing rubber enables more potential for final application as the healing occur at room temperature. For potential application stage, NR self-healing rubber was chosen as candidate material for puncture proof application. The self-healing natural rubber was able to recover the puncture spot ranging from 0.8 mm to 2 mm nail diameter at 100% recovery rate throughout pressure test, temperature test, repeatability test and stability test. Evidence for healed punctured spot was provided by SEM. Both self-healing NR and XNBR had exhibit significant performance on self-healing capabilities and mechanical properties. While on puncture-proof application, self-healing NR had shown a promising performance throughout all the test that has been conducted in this research.
- PublicationZero energy indoor vertical farming system with internet of things (IOT) monitoring(2023-08)This project proposes a zero-energy indoor vertical farming system that utilizes the Internet of Things (IoT) for monitoring and control. The method seeks to address issues with urban areas' lack of space, high energy use and lack of access to food. The proposed system integrates renewable energy sources, such as solar panels to power the vertical farming system and reduce the reliance on the grid. The system may be made to store extra energy produced throughout the day in batteries for use at night or at times when there is little sunlight. The idea of using 18V solar panel and 12V 4.5Ah lead acid battery will be applied in this project. Because the indoor atmosphere can be adjusted and optimized for plant development, it also enables agricultural production throughout the year, independent of the weather. Moreover, it makes use of IoT technology to monitor and regulate environmental elements like lighting and water level to enhance plant growth and save water usage. It reduces water consumption through the use of recirculating hydroponic systems based on real-time environmental data. There will be 3 water level sensors will be used in this project. Real-time data from the system's sensors may be examined and utilized to change agricultural conditions remotely, enabling effective resource management. Overall, the zero-energy indoor vertical farming system with IoT monitoring offers a sustainable and cost-effective solution for urban agriculture. It has the potential to revolutionize the way we produce food by reducing water consumption, optimizing crop growth and improving resource management. By integrating renewable energy and IoT technology, this system can contribute to both food security and environmental sustainability.
- PublicationInvestigation of the resistive switching properties and mechanisms of polymannose based memory devices(2023-05-01)Resistive random access memory technologies (ReRAM) are promising candidates for next-generation non-volatile memories owing to their simple device structure, low operational cost and power consumption and their compatibility with CMOS technologies. In addition, bio-organic materials are considered as prominent alternatives due to their biodegradability and benign environmental impacts. As such, the motivation behind this research is to determine the applicability of polymannose as a suitable bio-organic material for ReRAM applications utilizing a two-terminal structure. Polymannose thin-films were produced via drop casting a D-mannose powder and aqueous ethanol solution on ITO/PET substrate and dried at 160oC for different duration followed by Ag deposition as top electrode. Current–voltage (I–V) characterization was carried out and displays that resistive switching characteristics are achieved in the device when the precursor is dried between 4 - 7 h. The optimal drying time of 7 h provided optimal resistive switching characteristics, with a READ window of 2.2 V, high ON/OFF ratio of >105 at relatively low READ voltage of 0.01 V, acceptable endurance cycles of approximately 102, and a long retention time of >104 s. Further I-V analysis and HRTEM-EDS characterization reveal that high-resistance states (HRS) are governed by space charge limit current conduction resulting, while the low resistance states (LRS) are dominated by Ag metallic filaments. Furthermore, by modulating the compliance current, the polymannose successfully demonstrated twelve distinct and reliable LRS states at a READ voltage as low as -0.05 V. Moreover, the effect of fullerene (C60) on enhancing the performance of polymannose based ReRAMs has been studied. A memory device with Au-Pd/polymannose:C60/ITO/PET structure containing 5 vol% C60 has shown optimal ON/OFF ratio reaching ~105, a smaller read-memory window of 6.5 V and stable retention characteristics reaching 104 s. The electrical characteristics of the Au-Pd/polymannose:C60/ITO/PET shows a governing electronic conduction mechanism, and a model is proposed to explain the resistive switching mechanism for both device types. These results not only demonstrate the suitability of polymannose as a candidate bio-organic material for environmentally friendly high-density next generation non-volatile memories, but also show competitive performances that can potentially rival current materials used in ReRAM applications.
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- ItemAntidiabetic properties of andrographis paniculata and its possible mechanism of actions(2006)The study is aimed at a comprehensive initial pharmacological evaluation on Andrographis paniculata for further study as well as reconciling the previous scientific findings. Based on folklore claims and earlier scientific findings, the study was conducted to investigate and prove the antidiabetic properties of the plant. The study comprised pharmacological models which were either adopted or modified from conventionally used models. The models consist of in vivo, in vitro and ex vivo models. The in vivo models, either normal or experimental induced-diabetic rats were tested with Hypoglycaemic and Intraperitoneal Glucose Tolerance test (IPGTT). The aspect of acute single and chronic administrations was also taken into consideration. The blood glucose level was the main parameter measured in the models beside insulin level and physical or histological assessment of {3 cells. The in vitro consists of two models of Modified Averted Jejunal Sac Preparation and Isolated Abdominal Muscle Preparation. The RIN5f of f3 cells line was used as the ex vivo model. All tests in the experimental models were designed and tested with corresponding negative and positive controls. The plant extracts of different percentage of ethanol namely, 95%, 50%, 20% and 0% (water) ethanol extracts were investigated by the _models mentioned at the screening dose of 1 OOOmg/kg. The results showed that 20% ethanol extract possessed antihyperglycaemic effect in IPGTI on normal rats after single administration. And after fractionation the aqueous part of the extract was found to be active. On the other hand, the 95% and 50% ethanol extracts showed antihyperglycaemic effect in diabetic rats after 14 days during which twice daily doses were administered. All extracts positively showed the ability to promote rejuvenation of destroyed p cells and this result is maybe due to its antioxidant property. Furthermore the study also showed that there was significant reduction of insulin levels in the 95% and 50% ethanol treated rats. The reduction of both fasting blood glucose and insulin levels indicates that there was a possibility of increase receptors sensitivity towards insulin. In the Modified Averted Jejunal Sac Preparation, 95% and 50% ethanol extracts showed the inhibition of glucose absorption. However, all extracts significantly increase glucose uptake and act independently of insulin influence on the muscle. The result of cell line showed that none of the extracts stimulate the p cells to secrete insulin. The study managed to show that A. paniculata extracts particularly the 95% and 50% ethanol extracts have antidiabetic properties and act at different level of mechanisms either pancreatic or non pancreatic. The mechanisms are rejuvenating or promoting the growth of fJ cells, inhibition of glucose absorption in the intestine, increase glucose uptake in the muscle, and increase sensitivity of insulin receptors. These findings make the A. paniculata a promising remedy in treating both T1 OM and T2DM.
- ItemPerkembangan Tamadun Islam Di Sulawesi Selatan, Indonesia:Dari Perspektif Arkeologi Dan Sejarah(Universiti Sains Malaysia, 2013-10)Kajian ini bertujuan mendapatkan data dan maklumat yang lebih komprehensif tentang tamadun Islam di kawasan Sulawesi Selatan, khususnya dari segi taburan, asal usul, jenis, masa perkembangan, pengaruh budaya tempatan, makna yang dikandungi dan peranannya di Nusantara. Penyelidikan dijalankan dengan menggunakan dua kaedah iaitu, kaedah arkeologi dan kaedah sejarah. Jumlah tapak yang dikaji adalah sebanyak 29 buah. Hasil kajian menunjukkan bahawa masa awal Islamisasi iaitu, abad ke-16/17 Masihi, mendapat pengaruh yang kuat daripada budaya Melayu Islam. Jirat dan nisan makam yang pertama berkembang di kawasan berkenaan adalah jirat makam sederhana jenis peti batu, kemudian di atasnya dipacakkan nisan jenis Acheh bagi raja yang berkemampuan secara ekonomi atau jenis menhir bagi masyarakat biasa. Pada masa akhir abad ke-17 Masihi, mulai muncul budaya tempatan berakulturasi dengan budaya Islam Tanah Melayu. Makam-makam raja mulai dibuat megah. Memasuki abad ke-18 Masihi, budaya tempatan semakin kuat berperanan, iaitu menonjolkan unsur-unsur budaya pra Islam yang berkembang secara tempatan. Pada akhir abad ke-18 dan awal abad ke-19 Masihi, budaya tempatan semakin kuat dalam kewujudan tamadun Islam di kawasan tersebut, dengan anasir-anasir budaya megalitik yang kuat, dan bentuk-bentuk tamadun Islam dipengaruhi oleh faktor budaya tempatan. Tamadun Islam yang berkembang pada abad ke-17 hingga 19 Masihi, di Sulawesi Selatan bercirikan makam-makam bercorak Makassar dan Bugis yang juga ditemui di kawasan-kawasan lain di Nusantara.
- ItemCONSTRUCTION OF SMOOTH BICUBIC SURF ACES DEFINED OVER ARBITRARY QUADRILATERAL MESHES(2001-11)Two methods of modelling closed smooth precewrse bicubic surfaces on polyhedral mesh are described. The first method deals with the construction of bicubic B-spline basis functions. These functions are constructed on simple quadrilateral meshes, that is a closed polyhedral mesh in which every face has four edges and every vertex is the joint of three or four edges. These functions are used to model smooth closed surfaces from control polyhedron with quadrilateral faces. Geometric continuity is ensured at the extraordinary vertices and parametric continuity elsewhere. Surface splitting algorithm is applied in order to plot the surfaces. The second uses a subdivision approach to construct the surface. An algorithm to subdivide the surface recursively is proposed. By repeated subdivision, the surface is made to satisfy geometric continuity G1 around the extraordinary vertices and C1 elsewhere.
- ItemThe investigation on the barriers of green supply chain adoptions among SMEs in Penang: the role of business strategic orientation as moderator(2010)With the rapid growth and development of the industries, global warming and depletion of natural resources have become a concern for the society, government and the industry. Because of that, green topic has become an important issue. Although Penang government has put heavy resources and efforts to promote and encourage green initiatives, green supply chain has not been widely adopted by the industries in Penang especially SMEs. Thus, the purpose of this study is to investigate barriers that hinder SMEs in Penang from adopting green supply chain initiatives. In addition, it also investigates the moderating effect of business strategic orientation on the relationship between the barriers and green supply chain initiatives. To attain its’ objectives, questionnaire approach is adopted in this study and a sample of 92 respondents is collected through questionnaire method. SPSS statistical tool is used to test the descriptive and regression statistics. The result shows that the adoption of green supply chain initiatives by the SMEs in Penang is low. The reasons of low adoption of green supply chain initiative (green purchasing) are resource barrier and attitudinal and perception barrier. Technical barrier proves to be the factor that impedes the adoption of design for environment by the SMEs in Penang. However, the study found no convincing evidence to support the moderating effect of business strategic orientation on the relationship between the barriers and green supply chain initiatives. With the results and findings in this study, government and industry would have a better understanding of the barriers that faced by the SMEs. That allows government as well as big corporation to take corrective actions to drive and promote green supply chain initiatives across the entire supply chain.
- PublicationDevelopment Of W03-Tio2 Nanotube Arrays For Water Electrolysis(2013-03)Solar hydrogen generation from water electrolysis is a key target for the development of sustainable hydrogen economy for future energy system. The formation of self-organized Ti02 nanotubes without bundling is essential for high efficiency In photoelectrochemical (PEC) water electrolysis application. Comprehensive investigations on different parameters, such as composition of electrolyte, anodization time, anodization voltage, anodization temperature and heat treatment temperature were conducted in order to control the specific architecture of nanotubes.