52 research outputs found

    A study of printing plate mould development by using 3d printers for micro-flexographic printing process

    Get PDF
    Micro-flexographic is a new printing technique that has been implemented by combining flexographic printing and micro-contact printing technique. Flexographic printing is generally a high-speed production in roll to roll printing technique widely used in the graphic printing industry. Micro-contact printing technique is usually employed to produce fine solid line structures in micro to nano scale. Mould preparation for printing plate is also one of the vital parameters in micro to nano scale image printing. A precise mould could be used to produce the most accurate printing plate for micro-flexographic printing. The three dimension (3D) printer has the capability of producing fine solid lines below 100 Ī¼m in width and gap on master mould for the printing industry. This research elaborated the use of various 3D printers to produce a master mould for micro-flexographic printing. This paper investigated the capability of multiple 3D printers in creating micro to nano fine solid lines in the master mould for future development and application of printing in the electronic, graphic and bio-medical field

    Effects of different temperature profiles and corn-sago starch ratios on physical properties of extruded tilapia diets

    Get PDF
    Sago starch is a locally grown and produced starch resource in Malaysia. In this study, corn starch to sago starch ratios (CS:SS) of 0:20, 5:15, 10:10, 15:5 and 20:0 were included in feed mixture to contain 20% starch and produce five isonitrogenous and isocaloric (30% crude protein and 16.7 kJ/g, respectively) tilapia Oreochromis sp. diets. Diets were preconditioned to contain 40% moisture and extruded using a single-screw extruder at screw speed of 120 rpm using three different temperature profiles (I 60-100-140-180ĖšC; II 60-100-120-160ĖšC; and III 60-120-120-180ĖšC). Effects of these factors were evaluated on physical properties of extrudates including expansion ratio, bulk density, water stability, floatability, sinking velocity and durability. From the results, different temperature profiles and CS:SS had significant effects (p<0.05) on expansion ratio and floatability. Sago starch performed as a good binder as it gave higher percentage of water stability and pellet durability. The mixture with 10:10 of corn to sago starch extruded using temperature profile II (60-100-120-160ĖšC) produced the best extrudates with desirable physical properties

    Finite Element Simulation on Damage and Fracture Properties of a Ring Cut from Filament-Wound Pipes with and without Delamination

    Get PDF
    The technological advances in various industries have increased the demands on new engineered material tremendously since conventional materials such as steel, failed to perform in severe conditions. Nowadays, composite materials especially fibre-reinforced plastic composites (FRP) are broadly being used in many engineering fields to manufacture critical components with high stress concentration, exposure to extreme surrounding or weight constraint. However, they often suffer from a characteristic weakness, i.e. they are prone to interlaminar damage, often in a form delamination. In order to assess the development and the consequences of such damage, interlaminar fracture properties are essential. In this study, the ring cut specimen from filament-wound pipes with and without delamination was modelled and simulated based on experimental work using finite element modelling to further assist the identification and determination of the fracture properties. Investigation also involves the effect of the delamination length to the Energy Release Rate, G. Comparison between 23mm delamination of simulation and experimental results from [7] is presented

    The Implicit Contribution of Principalā€™s Self-Awareness Towards Teacher Self-Efficacy

    Get PDF
    The main focus of this study was to look at the influence of the authentic leadership of the principals and the self-efficacy level of teachers in Pendang district, Kedah. The quantitative survey method using the questionnaire was adopted in this study. The study respondents consisted of 254 teachers randomly selected from 10 national secondary schools in Penang district, Kedah. The benchmark used for authentic leadership is to use the Authentic Leadership Questionnaire (ALQ -Version 1) of the original instrument developed by Avolio, Gardner, and Walumbwa (2007). Similarly, the teacher self-efficacy questionnaire was used in Hoy and Woolfolk's (1993) short form of the Teacher Efficacy Scale developed by Moran, Hoy, and Hoy (1998). The findings show that there is a significant relationship between the dimensions of authentic leadership and the self-efficacy of teachers in Pendang, Kedah. However, there is only one dimension that influences the teacher's self-efficacy, which is the dimension of self-awareness. Based on the findings of this study, it is hoped that it will contribute useful information to help educators in cultivating the principals' leadership style and high levels of teacher self-efficacy to produce symmetrical human capital

    Air quality modelling using chemometric techniques

    Get PDF
    The datasets of air quality parameters for three years (2012-2014) were applied. HACA gave the result of three different groups of similarity based on the characteristics of air quality parameters. DA shows all seven parameters (CO, O3, PM10, SO2, NOx, NO and NO2) gave the most significant variables after stepwise backward mode. PCA identifies the major source of air pollution is due to combustion of fossil fuels in motor vehicles and industrial activities. The ANN model shows a better prediction compared to the MLR model with R2 values equal to 0.819 and 0.773 respectively.This study presents that the chemometric techniques and modelling become an excellent tool in API assessment, air pollution source identification, apportionment and can be setbacks in designing an API monitoring network for effective air pollution resources management.Keywords: air pollutant index; chemometric; ANN; ML

    Finite Element Simulation on Crack Analysis of a Thick-Tube

    Get PDF
    Most engineering failure began with cracks. Crack may caused by material defect, discontinuities in geometry or damage in service. Thus, Fracture Mechanics is introduced as a method for predicting failure of a surface containing a crack. This project is focusing on pre-existing crack with assumption that no microscopic defects are presents. Linear Elastic Fracture Mechanics (LEFM) is used to evaluate the Stress Intensity Factor (SIF) of the specimen. Further analysis is done by incorporating Elastic Plastic Fracture Mechanics (EPFM) to understand the crack growth over period of time. In this study, the important parameters in fracture mechanics such as Stress Intensity Factor (SIF), Crack Mouth Opening Displacement (CMOD), J Integral and stable crack growth are been investigated. A complex loading simulation of NKS-3 specimen is done using finite element modeling. The NKS-3 is a thick-tube used in Pressurized Water Reactor (PWR) which has a circumferential flaw on its inner surface. The cylinder is loaded with axial tensile load and internal pressure combined with thermal shock. A 2-Dimensional Axysimmetric-4 nodes element with focused mesh at the crack tip is employed in the simulation. Several analyses have been done using hardening data at different temperature. A comparison of solution is made for simulation with and without thermal load history. Further analysis showed that the stable crack growth is estimated to be around 3.0mm

    Investigating the Potential of Flexible and Pre-Organized Tetraamide Ligands to Encapsulate Anions in One-Dimensional Coordination Polymers: Synthesis, Spectroscopic Studies and Crystal Structures

    Get PDF
    Published: 19 January 2021The synthesis of amide-based molecules, possessing pre-organized structures, has received significant attention due to their potential applications as molecular receptors and as components of nanomaterials. In this study, four extended tetraamide ligands incorporating ethylene and propylene spacers, namely 1,2-bis[N,Nā€²-6-(3-pyridylmethylamido)pyridyl-2-carboxyamido]ethane (L1), 1,2-bis[N,Nā€²-6-(4-pyridylmethylamido)pyridyl-2-carboxyamido]ethane (L2), 1,2-bis[N,Nā€²-6-(3-pyridylmethylamido)pyridyl-2-carboxyamido]propane (L3) and 1,2-bis[N,Nā€²-6-(4-pyridylmethylamido)pyridyl-2-carboxyamido]propane (L4), were successfully synthesized. Further, reaction of L2 and L4, incorporating pendant 4-pyridyl donors as the metal coordinating sites, with cadmium salts, produced two close-packed one-dimensional coordination polymers, {[Cd3(L2)4(H2O)10](NO3)6Ā·12H2OĀ·CH3OH}n and {[Cd(SO4)(L4)(H2O)2]Ā·4H2OĀ·CH3OH}n. X-ray crystallography reveals that the flexible tetraamide ligands fold upon themselves in the coordination polymer structure. As a consequence, the anion pocket in {[Cd(SO4)(L4)(H2O)2]Ā·4H2OĀ·CH3OH}n incorporating the ligand with the propylene spacer was blocked from encapsulating charge-balancing anions, which were involved in bridging the di-cadmium units. Interestingly, a strong interaction between the 2,6-pyridine dicarboxamide moiety with the nitrate anions was found in {[Cd3(L2)4(H2O)10](NO3)6Ā·12H2OĀ·CH3OH}n, showing potential for materials made from these ligands to serve as anion receptors.Nur Shuhaila Haryani Haris, Nafisah Mansor, Mohd Sukeri Mohd Yusof, Christopher J. Sumby and Maisara Abdul Kadi

    Dehydration of traditional dried instant noodle (mee siput) using controlled temperature & humidity dryer

    Get PDF
    Drying process is an essential step to produce instant noodles. Yet, the industries especially Small and Medium Enterprises (SMEs), is seeking for an efficient method to dry the noodles. This paper discusses the performance of an invented drying system which employed heating and humidifying process. The drying system was tested using 30 kilogram of the raw noodle known as ā€œMee Siputā€. Temperature controlled system were used in the study to control the temperature of the drying process and prevent the dried noodles from damage by maintaining the temperature of lower than 80oC. The analysis shows that the system was drastically decreased the humidity from 80% to 40% just after 200 minutes of the drying process. The complete dehydration time of noodle has also decreased to only 4 hours from 16 hours when using traditional drying system without sacrificed the good quality of the dried noodle. In overall, the invented system believed to increase the production capacity of the noodle, reduce cost of production which would highly beneficial for Small Medium Industries (SMEs) in Malaysia

    Determination of fibernolytic enzyme activities of white rot fungi isolated from oil palm fronds

    Get PDF
    Oil palm fronds (OPF) is widely used as the source of roughage for the farm animals. However, the full potential of OPF as animal feed is limited by their high lignin content which limits the rumen microbeā€™s access to the cellulose and hemicellulose. White rot fungi (WRF) are a group of fungi belonging to basidiomycete phylum and are commonly found in decaying woody plant. They possess the ability to degrade lignin. This experiment aims to identify the phylum of the best lignin decaying fungi based on their enzymes activity. In this experiment, 11 fungi species were isolated from decaying oil palm fronds. They are labelled as WR1, WR 2, WR3, WR4, WR5, WR6, WR7, WR8, WR9, WR10 and WR11. Their fibernolytic enzyme activities which includes laccase, manganese peroxidase, lignin peroxidase, avicelase, carboxylmethylcellulase and xylanase are analysed using the solid state fermentation method. It is was found that 5 fungi species which are the WR1, WR2, WR4, WR7 and WR10 produced the highest ratio of lignin degrading enzyme to cellulose and hemicellulose degrading enzyme. The fungi are then analysed under microscope to determine the phylum of the fungi. From the observation, the fungi are identified to belong to the phylum basidiomycetes due to presence of clamp connection

    The application of One Health concept to an outdoor problem-based learning activity for veterinary students

    Get PDF
    Background: The One Health (OH) approach, which seeks to bring together human and animal health, is particularly suited to the effective management of zoonotic diseases across both sectors. To overcome professional silos, OH needs to be taught at the undergraduate level. Here, we describe a problem-based learning activity using the OH approach that was conducted outdoors for 3rd-year veterinary students in Malaysia. Materials and Methods: A total of 118 students, divided into two groups, completed the activity which spanned 11/2 days at a deer park adjacent to a wilderness area. Students were asked to evaluate the activity using an online survey that had quantitative and qualitative components. Results: Response rate was 69.5%. The activity was rated excellent by 69.5% and good by 30.4%. Levels of satisfaction were high on a range of criteria. 97.5% of students intended to take action in their studies as a result of what they had learned. Conclusions: Delivery of an outdoor problem-based learning activity using OH approach was very successful in terms of participation, knowledge delivery and understanding, and the willingness of students to integrate OH into their future practice. For the improvement of future programs, the involvement of other disciplines (such as Medical, Biology, Biotechnology, Biomedical, and Public Health) is being considered
    • ā€¦
    corecore