13474 research outputs found
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A critical genre analysis of the user requirement specification report in the information technology industry / Shahizan Shaharuddin
No full textWhile it has been established that discursive practices involving writing are highly situated and context-bound, few local studies have examined the processes involved in the construction of texts and the shaping of the intended text. Recent perspectives on writing as ways of working and acting, and texts as social action suggest that studying the processes behind the construction of a text could provide a clearer understanding of the discursive practices involved in the shaping of the text. This is seen as relevant to professional writing context in the present study as texts are often shaped to facilitate the social action of their users (Pare, 2015). Therefore, this study aims to investigate the processes involved in the construction of an information technology (IT) document called the User Requirement Specification (URS) report. This URS report is situated within the documentation practices of an IT development project involving the revamping of a client’s portal website. Using Rhetorical Genre Studies (Miller, 1984; Artemeva, 2009) as the main theoretical framework, the study employed interviews, document analysis and field notes to investigate the discursive practices involved in the shaping of this URS report. Thus, the study involved looking at the processes of text construction as well as into the text as an attempt at explaining the rhetorical and linguistics aspects of text construction. Based on the discourse analysis of interview transcripts report documents and the final URS report, findings revealed that the processes involved in the URS construction were based on three main concerns: the client’s needs and demands; the stipulated requirements and allowed format of the report (the template); and shared objectives of the project’s outcome. However, the writer and contributors to the text were able to exercise agency in recommending what could benefit the client and end-users of the portal in the long run. This is reflected in the discursive features of the final URS document. Examining the processes of the URS construction was useful to the study as it revealed the collective involvement of different teams and their communication that led to the production of URS report. It is hoped that the findings would be applicable in the context of technical report writing with helpful implications to professional context and the IT world
Synthesis of eco-friendly nanofluids for enhancement of heat transfer and application in different flow configuration passages / Asif Khan
No full textSince the invention of the heat exchangers, the working fluids such as water, ethyl glycol, oil and many others were used, however, they reveal relatively low thermal conductivity. Eco-friendly nanofluids and the cost-effective annular heat exchangers were introduced in this research to overcome the problem. In the present work, heat transfer coefficient and friction loss analyses of (TiO2 and GNP) water-based nanofluids were compared with DI-water flowing in annular conduit under turbulent flow regime. The nanoparticle weight concentrations of 0.1, 0.075, 0.05 and 0.025 wt.% were prepared by using a simple two-step method. The DI-water simulations were conducted by using ANSYS Fluent 18.2 (CFD commercial package) under steady turbulent flow conditions at high Reynolds number and constant heat flux boundary conditions with the varied inner flow passage configuration of the annular heat exchanger. The CFD analyses used the finite volume method, uniform surface heat flux boundary condition and SST-k-? model for the solver. The DI-water simulation demonstrated, the increase of the inner wall temperature in the square passage incomparison to the circular inner geometry. The experimental results exhibited the convective heat transfer coefficient enhancement with the increase of nanoparticles concentrations in the base fluid. The maximum Nusselt number and insignificant increment of friction factor resulted in the addition of nanoparticle into the base fluid. The remarkable enhancement of the heat transfer achievement were, 21.75% and 11.72% for the 0.1 wt.% of GNP-water and TiO2-water nanofluids over the base fluid in the turbulent flow regime. The results concluded that varying inner shape of the annular conduit and addition of nanoparticles enhances the rate of heat transfer and retards the energy consumption
Study of heat and momentum transfer to colloidal suspensions in annular closed conduit flow / Shoaib Sadik
No full textWith the advancement of science and the rapid growth of industries and the improved lifestyles of people, energy consumption has been increasing. Whereas the exploration of energy remained at a slower pace and the energy reservoirs are extinguishing at a faster rate. High energy consumption is also encouraging environmental pollution and global warming. Considering all these issues, scientists and engineers are desperately exploring highly efficient heat exchangers for the conservation of energy and minimize its losses. The present research has focused on obtaining highly efficient heat exchangers. Lots of research have performed on the improvement of heat exchanger materials, alteration of process parameters, and enhancement of surface areas but there are limited works on exploration and use of high thermal performance heat exchanger liquids. The present research was focused on the synthesis and application of high thermal performance nanofluid for efficient heat exchangers of circular concentric annular flow passage configuration. Aluminium oxide nanoparticle-based suspension fluids of low concentrations (0.025 to 0.1 vol. %) were prepared using probe sonicator and applied in the annular heat exchanger for heat transfer and friction loss analyses. No additives were selected to ensure the environmental protection. There were 3.4 to 17% enhancement in heat transfer coefficient over water alone in the Reynolds number range of 2.4 to 4.8×103. As the annular flow passage in heat transfer applications is common, so the present findings will provide some information to the researchers and support in the design of more efficient heat exchangers
Engineering properties and microstructural characteristics of cement and geopolymer based mortars using nontraditional supplementary cementitious materials / Sumesh Mathialagan
No full textThe concrete repair and rehabilitation industry grows rapidly due to deterioration, damage and defects in concrete structures. For various reasons, the concrete construction industry is not sustainable; because it consumes huge quantities of virgin materials, the usage of Portland cement as prime binder. The production of cement is a major contributor to greenhouse gas emissions. In addition, the high cost of commercial repair material. Therefore, it is necessary to develop cost-effective alternative repair materials for concrete repairs. There have been many standard repair materials available in the market, which are costly and not affordable to common people. However, research works on the use of alternative, non-traditional pozzolanic materials in repair and rehabilitation is gaining momentum. Industrial wastes and by-products such as palm oil fuel ash (POFA), palm oil clinker (POC), ground granulated blast furnace slag (GGBS), bottom ash (BA), and fly ash (FA) have shown promising results as pozzolanic materials. As the world’s second-largest palm oil producer, Malaysia has abundant industrial by-products of POFA and POC. The by-products of palm oil industries are signified as non-traditional supplementary cementitious materials, which have not been addressed in the previous research works as repair mortars. The present study focused on cement and geopolymer-based mortars with partial replacement of POFA, treated palm oil fuel ash (TPOFA), POCP and BA. GGBS and FA were utilized as source material for geopolymer mortars. The significant parameters were investigated on association with the better understanding of the interfacial transition zone, microstructures, setting behavior, mechanical properties, bond strength and durability in accordance with ASTM standard. Ordinary Portland cement (OPC) was partially replaced by POFA, TPOFA, POCP and BA at 0%, 10%, 20% and 30% by weight. For geopolymer mortars, GGBS was replaced with 20%, 30% and 40% of POFA, TPOFA, POCP and BA by weight. The chemical composition and morphology of binders were examined by X-ray florescence (XRF) and scanning electron microscope (SEM) techniques, respectively. Microstructure of mortar was investigated using SEM, X-ray Diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR) and Thermogravimetric analysis (TGA). Among all the non-traditional SCMs, TPOFA achieved a satisfactory performance in all the investigation conducted. The mortars with TPOFA as the replacement of cement for 10%, 20% and 30% produced higher compressive strengths of 101.8, 88.4 and 83.6 MPa, respectively at 90-day. In case of geopolymer mortar, 30% replacement of GGBS with TPOFA attained the highest 28- day compressive strength of 82.45 MPa. Formation of CH and C-S-H was confirmed by XRD, FTIR and TGA in cement-based mortars. The formation of C–A–S–H gel was identified in GGBS based geopolymer mortars. Moreover, the strength activity index assessment found that pozzolanic activity of TPOFA and BA is better than POCP and POFA based mortar specimen. It is recommended that 10% of pozzolanic cementitious material of POFA, TPOFA, POCP and BA could be used to replace OPC and for geopolymer-based mortars, 30% of pozzolanic cementitious material can be used to replace GGBS in the development of geopolymer mortars in order to develop high strength mortar in the range of 60-100 MPa
Antibacterial action of graphene oxide towards bacteria and its toxicological effects on human epidermal keratinocytes / Thiruchelvi Pulingam
No full textThe antibacterial nature of graphene oxide (GO) has stimulated wide interest in the medical field. Although the antibacterial activity of GO towards bacteria has been well studied, a deeper understanding of the mechanism of action of GO is still lacking. The objectives of the study were to characterize the physicochemical properties of GO, to determine the antibacterial and antibiofilm activity and the mechanistic action of GO against Gram-positive Staphylococcus aureus and Enterococcus faecalis and Gram-negative Escherichia coli and Pseudomonas aeruginosa, to determine the synergistic behaviour of GO with selected antibiotics against bacterial cells in suspension and biofilm and to determine the in vitro toxicological effects of GO against human epidermal keratinocytes (HaCaT). GO was characterized using Ultraviolet-visible (UV-VIS), Raman and Attenuated Total Reflectance-Fourier-transform infrared (ATR-FTIR) spectroscopy techniques, Field Emission Scanning Electron Microscopy (FESEM), Transmission Electron Microscopy (TEM) and X-Ray Diffraction analysis (XRD) techniques. Viability, time-kill and Lactose Dehydrogenase (LDH) release assays were carried out to determine the antibacterial activity of GO towards bacterial cells in suspension and biofilm while FESEM and TEM analysis were conducted for GO treated bacterial cells in suspension. Interactions at molecular level between GO and antibiotics were analyzed using ATR-FTIR and UV-Vis techniques. Increase in the activity of antibiotics through the addition of GO was investigated using selected antibiotics such as ampicillin, chloramphenicol and tetracycline. Additionally, toxicity of GO towards HaCaT cells were examined through 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) viability, reactive oxygen species (ROS) detection and LDH release assays while surface morphology of GO treated HaCaT cells were analyzed using FESEM. Characterization techniques confirmed the presence and morphology of GO in sheet-like formation. Antibacterial activity of GO was concentration and time-dependent for the bacterial cells in suspension. Optimal GO concentration with more than 60% of bacterial cell death was at 10 μg/mL. In contrast, GO enhanced the viability of the biofilm cells when treated with higher concentrations and for longer exposure period. Loss of membrane integrity among bacteria in suspension was enhanced with increasing GO concentrations and this corresponded to the elevated release of LDH in the reaction medium. Bacterial cell morphology of GO treated bacterial culture showed apparent differences in the mechanism of action of GO towards Gram-positive and Gram-negative bacteria. ATR-FTIR characterizations of the GO treated bacterial cells showed changes in the fatty acids, amide I and amide II of proteins, peptides and amino acid regions compared to untreated bacterial cells. The ATR-FTIR and UV-Vis characterizations of GO and antibiotics showed adsorption of tested antibiotics onto GO through molecular interactions. The combinatorial antibacterial activity of GO and antibiotics towards bacteria in suspension was found to be increased when compared to GO or antibiotic alone but no changes were observed with the biofilm cells. Cytotoxicity of GO was found to be dose dependent towards HaCaT cell line and hence it is suggested to impose only low toxic effects against the epidermal keratinocytes. Therefore, this study reaffirms that GO has strong antibacterial potentials and could act as an adjuvant to enhance the antimicrobial activity of antibiotics
Synthesis, structure elucidation and selected biological activities of Ag(I) and Au(I) complexes constructed from thiosemicarbazone and phosphine ligands / Syahrina Nur ‘Ain Abdul Halim
No full textNew Ag(I) and Au(I) mixed ligand complexes were synthesised using thiosemicarbazone and phosphine in search of a new biologically active compounds. CHN elemental analysis, powder X-ray diffraction (PXRD), single crystal X-ray diffraction as well as several spectroscopic techniques such as FT-IR, Energy-dispersive X-ray (EDX), 1H, 13C, and 31P{1H} NMR were performed to elucidate the structure of these complexes. Elemental analysis suggested that the stoichiometry of the complexes formed by the reaction of Ag nitrate with thiosemicarbazone in the presence of phosphine was indeed 1:2:1 molar ratio, while for the Au to be in 1:1:1 molar ratio. The Ag and Au were discovered to be coordinated to the sulphur of thiosemicarbazone and phosphorus of phosphine, having a tetrahedral and linear geometry respectively. The in-vitro antiproliferative activity of these Ag(I) complexes was investigated towards the MDA-MB-231 and MCF-7 breast cancer cell lines, as well as the HT-29 colon cancer cell line, which yielded IC50 values in low micromolar range. The antiplasmodial activity of these Ag complexes was also examined against chloroquine-resistant P. falciparum parasite which demonstrated good activity and further tested for their selectivity index. As for the Au(I) complexes and its free ligands, their antibacterial activity were tested against E. coli and S. aureus and the result shown that the ligands exhibited higher activity. Preliminary results of transforming the gold complexes to metal clusters by chemical reduction are also discussed in this thesis
Prospects of incubation in supporting agrobased industry: Evidence from Malaysian agricultural research and development institute / Sarpaneswaran Subramaniam
No full textAgricultural incubation system plays an essential role in fostering the national agriculture systems. This study is mainly based on a single public agricultural research institution in Malaysia, which is, Malaysian Agricultural Research and Development Institution (MARDI). The main objective of this study is to examine the relevance of incubator support system in fostering capabilities development of incubatees. In this regards, the selected four MARDI’s agro-based incubatees have been studied qualitatively via indepth interviews. The emphasis is on assessing the different supports system at different incubation stages since there is lacking comprehensive studies on monitoring the agrobased incubatee business performance during and post-incubation periods. The case studies provide useful insights into the learning process i.e. (knowledge creation, knowledge absorption, and knowledge dissemination) and capabilities building i.e. (marketing, product development, and production technology development) take place in driving incubatee business performance during and post-incubation periods. In addition, the study further examines the challenges faced by incubatees at different incubation phases to develop the essential capabilities in accelerating their business performance. The main findings from the case studies indicated that there are mismatches in terms of services rendered by MARDI incubators to incubatees during incubation period which are significantly hindering incubatee’s business performance. This study highlights the variation in terms of organisational learning and capabilities development between graduated and non-graduated incubatees that are significantly reflecting their business performance. The key findings show that in order to strengthen the MARDI incubation system to support new ventures in the agriculture sector, MARDI should advance crucial support services to incubatees particularly during post-incubation period
Penyeliaan instruksional, kepercayaan kepada penyelia, dan kapasiti guru sekolah menengah / Mislinah Makin
No full textDalam melaksanakan transformasi pendidikan, pemimpin sekolah perlu memberi sokongan kepada guru untuk meningkatkan keberkesanan pengajaran dan pembelajaran dalam bilik darjah. Amalan penyeliaan instruksional yang berkesan mampu meningkatkan kapasiti guru dalam melaksanakan tugas mereka di dalam bilik darjah. Namun, tidak banyak bukti empirikal yang mengkaji hubungan antara pemboleh ubah tersebut khususnya dalam konteks Malaysia. Berdasarkan tinjauan literatur berkaitan amalan pelaksanaan penyeliaan instruksional, pengkaji mendapati bahawa guru-guru masih kurang jelas tentang proses pelaksanaan penyeliaan instruksional. Oleh itu, tujuan kajian ini adalah untuk mengkaji amalan penyeliaan instruksional yang dilaksanakan di sekolah, khususnya konstruk kemahiran penyelia dan bantuan langsung, dan hubungannya dengan kapasiti guru. Selain itu, kajian ini juga bertujuan untuk mengenal pasti peranan konstruk kepercayaan kepada penyelia sebagai mediator antara konstruk kemahiran penyelia dan bantuan langsung, terhadap konstruk kapasiti guru. Responden kajian terdiri daripada 390 orang guru yang diperoleh melalui pensampelan pelbagai peringkat (multi-stages sampling). Kajian ini mendapati bahawa dalam amalan penyeliaan instruksional, konstruk kemahiran penyelia adalah pada tahap yang tinggi apabila skor min melebihi 4.0; manakala konstruk-konstruk lain, iaitu bantuan langsung, kepercayaan kepada penyelia dan kapasiti guru berada pada tahap sederhana apabila skor min berada di antara 3.0 hingga 4.0. Berdasarkan nilai goodness of fit, hasil analisis SEM dalam kajian ini mendapati bahawa model kajian yang dibentuk adalah fit dengan RMSEA 0.9. Dapatan ujian SEM juga menunjukkan terdapat kesan positif yang signifikan antara ketiga-tiga konstruk iaitu konstruk bantuan langsung, konstruk kemahiran penyelia dan konstruk kepercayaan kepada penyelia dengan konstruk kapasiti guru. Analisis terhadap peranan mediator menunjukkan bahawa konstruk kepercayaan kepada penyelia berperanan sebagai mediator separa dalam hubungan antara konstruk bantuan langsung dengan konstruk kapasiti guru. Pada masa yang sama konstruk kepercayaan kepada penyelia juga berperanan sebagai mediator separa antara konstruk kemahiran penyelia dengan konstruk kapasiti guru. Kajian ini juga membangunkan model yang menunjukkan hubungan antara tiga konstruk penyeliaan instruksional dan konstruk kapasiti guru
Abundance and distribution of microplastics and phthalic acid esters in selected mangrove areas in Peninsular Malaysia / Norkhairah Anuar
No full textContamination of microplastics in mangrove has been receiving growing attention as experts reckon 30 billion tonnes of plastics will accumulate in 2050. The vast increase in plastic commodities will increase microplastics abundance in mangroves as mangroves are substantially sinks and traps for plastic debris. Due to persistent properties and high surface to volume ratio of microplastics, Phthalic Acid Esters (PAEs) can be taken up by microplastics, representing a grave threat to the ecosystems. This study investigated the abundance and distribution of microplastics and PAEs in selected mangrove areas in Peninsular Malaysia. The objectives of this study are to identify the anthropogenic activities that may contribute to the abundance of microplastics and PAEs in selected mangrove areas, to determine the abundance and distribution of microplastics and PAEs, and to analyze the relationship associated between them. The prevalence of microplastics and PAEs were studied in six mangrove areas, distributed across the West Coast (Matang, Serkam, and Kukup) and the East Coast (Sedili Besar, Cherating, and Semerak) of Peninsular Malaysia. Anthropogenic activities were identified through observation of 5 km radius surrounding the sampling areas. For sampling of mangrove sediment, three depths from the surface were chosen (1-3 cm, 3-6 cm, and 6-9 cm) at three locations within each mangrove area. Microplastics in surface water were collected using plankton net. The microplastics from sediment were extracted using floatation technique before passing through a set of Tyler sieve of mesh sizes 5.0 mm, 1.0 mm, and 0.5 mm. Likewise, surface water sample was passed through the Tyler sieve of similar aforementioned mesh sizes. The extracted microplastics were treated with 20% alcohol solution overnight and grouped according to size, type, and colour. Soxhlet Extraction and Liquid-liquid Extraction were performed to extract PAEs, followed by GC-MS/MS analysis as the instrumental analysis. Matang, as compared to the other mangroves, has become a subject to high anthropogenic pressure as the area demonstrates the highest number of anthropogenic activities. On average, the highest microplastics concentration in mangrove sediment was found in Matang (65.18 ± 12.34 particles/kg) and in surface water was discovered in Serkam (0.0125 ± 0.0031 particles/m3). The majority of microplastics found in mangrove sediment were 1.0 to 5.0 mm in size, films, with blue and white in colour, whereas most of the microplastics identified in surface water were 0.5 to 1.0 mm in size, fragments, and colour categorized as others. The type of PAEs found were Phthalic acid, bis(7-methyloctyl) ester; 1,2-Benzenedicarboxylic acid, mono(2-ethylhexyl) ester (MEHP); 1,2-Benzenedicarboxylic acid, diisooctyl ester (DIOP); and Decanedioic acid, bis(2-ethylhexyl) ester (DEHS). The total concentration of PAEs recovered from mangrove sediment and surface water were 2060.13 ppm and 670.73 ppm, respectively. Results demonstrated an inverse relationship between microplastics abundance and PAEs concentration in mangrove sediment. This suggests that higher microplastics abundance is observed in sediment with lower PAEs concentration. The findings from this research are vital to set baseline database on microplastics and PAEs pollution, for assessment of future policy measures and as information for managerial actions
Development of collaborative flipped instruction for form one Malay language writing / Nurul Hijja Mazlan
No full textThe aim of this study is to develop a Collaborative Flipped Instruction for Form One Malay Language Writing through Design and Development Research. Declared a national language in Malaysia, Malay language is a compulsory subject in the national education system. Although many students in Malaysia have passed their Malay language papers on national examinations, their language skills, including writing, are evidences of conflict. Backlog issues related to Malay language writing are not limited to the writing skills themselves, but are also demonstrated by the low rate of technology integration in its writing instruction. Comprised of three phases – Needs Analysis, Design and Development, and Implementation and Evaluation, multiple methods have been used in each phase to achieve the objectives. During the Needs Analysis phase, Malay language teachers in Kuala Lumpur were interviewed, surveys were conducted among eighty-seven Form One students from national secondary school in Kuala Lumpur, and document analysis of writing artifacts and statistical documents was conducted. These triangulation methods have been used to analyze the needs in the Collaborative Flipped Instruction for Form One Malay Language Writing. The analysis of needs involved content, technology and infrastructure, as well as situational factors-focused on user needs and localized background issues. The aim is to inform the next design process. The Design and Development phase is the next step, using rigorous methods – an interview with four experts and a consolidated consensus of eighteen experts through the Fuzzy Delphi method. The development of the module was then proceeded based on the result of the design phase. The final phase is the Implementation and Evaluation in which the usability of the module was investigated through interviews with seven Form One students and their Malay language teacher at the national secondary school in Kuala Lumpur. They were involved in the implementation of the flipped instruction. Results from the Needs Analysis phase have shown that tacit knowledge of the writing process is the main issue lingered around teachers, negatively affecting the development of writing skills among students. Besides that, individual factors coupled with pedagogy issues also contributed to the problems. The study also investigates the pattern of technology usage among students and teachers. There is, therefore, a need for research-based writing instruction, taking into account students' inclination towards social media technology. Meanwhile, the findings of the Design and Development phase identified the components and sub-components of the Collaborative Flipped Instruction for Form One Malay Language Writing based on expert consensus. Next, the findings of the Implementation and Evaluation phase investigated the flaws and strength of the module, as well as the suggestions for improvement from the users’ retrospective. Implications and recommendations for future researchers and practitioners were then presented