Universiti Putra Malaysia
Download Latest Complete Journal - JST Vol. 24 (1) Jan. 2016
Foreword by the Chief Executive Editor
Full Article
(Downloads: 274)
Abstract (Viewed: 26)Quality Function Deployment (QFD) is a structured methodology that uses customer and technical requirements for designers and manufacturers to provide better products. Many researchers combine or integrate the technique of QFD with other methodologies such as Theory Inventive of Problem Solving (TRIZ) or Design for Manufacture and Assembly (DFMA) to optimise product design innovation and improvement. The combined methodologies are even used to solve process problems. Initial literature review of the application of stand-alone QFD poised several problems. Combining QFD with other techniques, such as TRIZ and DFMA, has helped to address these issues and forms the basis of future research. The integrated methods can solve main contradictory problems more precisely from product demand analysis to product design, production and application. Review work of the literature, specifically that on research and development of QFD, TRIZ and DFMA, showed that the said methodologies have been widely and successfully implemented in several practical applications such as resolving conflicts between customer and technical/engineering requirements and reducing production cost. This review work provides an in-depth analysis of identifying and finding issues of strengths, weaknesses and outcomes of the QFD when combined with TRIZ and also of QFD integrated with DFMA.Product design, QFD TRIZ, DFMA.
Full Article
(Downloads: 179)
Abstract (Viewed: 47)Concrete is a very complicated, random, multi-scale and multi-phase material. It is important to know cement paste structure to understand its properties and damage mechanisms that can influence the properties of concrete. Recently, many researchers have focused on the simulation of hydrated cement microstructure to figure out how damage/deterioration might be initiated. Moreover, as the microstructure of hydrated cement is known, we are able to produce greener, stronger and more durable concrete. There is a critical need to survey previous research to direct future study. In recent years due to development of advanced computers, most researchers tend to study the atomistic structure of hydrated cement and to make a bridge between nano and macro scales. Various models have been developed to simulate cement structure. This paper is an introductory review of the most important studies proposed by researchers for simulation of hydrated cement at different scales varying from nano to macro. Impact of the latest advances in simulation methods and their applications for hydrated cement research is investigated. Salient issues are categorised into four main sections including numerical models, microstructural models for cement hydration simulation, atomistic simulations and multi-scale studies.Atomistic simulation, cement, C-S-H, hydration, microstructure, multi-scale
Full Article
(Downloads: 111)
Abstract (Viewed: 50)Development of the positron emission tomography (PET) diagnostic radiopharmaceutical (18F) fluoro-2-deoxy-D-glucose (18F-FDG) subsequently facilitated the discovery and clinical evaluation of several new tracers as imaging markers for cancer. While 18F-FDG is a widely employed marker forenhanced intracellular glycolysis and metabolic function, one of the newer tracers, (18F)-3'-fluoro-3'deoxythymidine (18F-FLT), has been developed as a biomarker for cell proliferation. In this review, the potential of 18F-FLT as a biomarker for cancer imaging is discussed.18F-FLT, 18F-FDG, Positron Emission Tomography (PET), cellular proliferation
Full Article
(Downloads: 76)
Abstract (Viewed: 2)The steady two-dimensional laminar mixed convective boundary layer flow of a viscous incompressible electrically conducting Newtonian fluid along a moving stretching sheet embedded in a porous medium was studied numerically. We used temperature dependent viscosity and thermal conductivity and concentration dependent mass diffusvity. Further, the velocity and thermal slip boundary conditions were applied at the surface of the sheet. The governing transport equations were reduced to similarity equations using scaling group of transformation, before being sloved numerically by using the fourthfifth order Runge-Kutta-Fehlberg method from Maple 13. Our analysis revealed that the mass diffusivity parameter causes both temperature and concentration to increase whilst thermal conductivity parameter increases the temperature. It was also revealed that the rate of heat and mass transfer increased with the increasing of velocity slip, viscosity and power law parameters. Comparisons with previous published works are reported and good agreements were found.Variable transport properties, double-diffusion, Lie group, velocity and thermal slip, MHD
Full Article
(Downloads: 74)
Abstract (Viewed: 3)The morphological and physico-chemical properties of 11 soil series representing the major soil types in the Tasik Chini catchment in Pahang, Malaysia were studied. Soil types of the study area showed wide variations in their morphological and physico-chemical properties as a result of mean annual precipitation, soil parent material, vegetation and topography. Analyses showed that low values of silt were recorded in the horizon and the content of clay increased with soil depth. All the soil series contained low amounts of organic matter. Physical properties showed higher values for bulk density in the disturbed soils compared to the undisturbed forest soils. Regarding the chemical properties, these soils were strongly acidic. Electrical conductivity was also very low. Due to low pH, the contents of exchangeable base in all the soil types were very low. The cation exchange capacity of all the soil series were low with values less than 13.34 meq/100g soil.Soil series, morphology, physico-chemical properties, soil profile, Tasik Chini
Full Article
(Downloads: 60)
Abstract (Viewed: 7)Flow-through catalytic membrane system for ester production is one of the competitive alternatives to the conventional esterification system. This article presents the development of an integrated reaction/regeneration unit that was established to study the reaction followed by the regeneration step using two consecutive membrane reactor units working alternately. The hypothesis led to continuous ester production with a relatively high average conversion. The esterification reaction conversion of ethylhexanoic acid with ethanol and acetic acid with ethanol using catalytic membrane reactor reached up to 97.7% and 96%, respectively at room temperature after a reaction time of 10 sec, then slowly decreased; this is attributed to the decrease of catalytic membrane efficiency due to water adsorption on active functional groups, making a regeneration step mandatory. The developed unit was used to produce biofuel/biodiesel by esterification of acetic acid and fatty acid with ethanol.Catalytic membrane, esterification, regeneration, integrated pilot unit
Full Article
(Downloads: 44)
Abstract (Viewed: 2)The hyper competitiveness of medium-size enterprise is not only heavily dependent on its cloud computing infrastructure evolution but also on its adaptation for sustainability to global web interconnection ecosystems. While the bigger multinationals have experienced positive business values due to their economies of scale, the medium-size manufacturing plant still faces greater challenges. We update the view on two similar but evolved theoretical perspectives from Harvard University: Commodity of IT infrastructure and Disruptive Technology into a catalyst model for optimum technology maximisation. This paper proposes the establishment of a new dynamic barebones yet optimised internet infrastructure that will integrate the existing client server into the extranet to form an extended cloud environment. The study's three-stage primary data collection procedure consistently validated our findings. Our results suggest that enterprise should continue to invest in optimised IT infrastructure despite the economic turbulence for competitive gearing in the future.Cloud computing, economic turbulence, exostructure, framework, IaaS, ICT infrastructure, Small and Medium Size Enterprise
Full Article
(Downloads: 55)
Abstract (Viewed: 4)Dilute acid hydrolysis and enzymatic hydrolysis were sequentially combined for the purpose of producing fermentable hydrolysate from cocoyam starch. A three variable Box Behnken design was used to study the effect of temperature, time and acid concentration for the acid hydrolysis step while for the enzymatic hydrolysis step, the variables optimised were temperature, time and pH. A total of 17 individual experiments were generated for each step of the hydrolysis and were used to develop regression models for each step. The regression models developed to represent the acid and enzymatic hydrolysis steps were statistically significant (p<0.05) and did not show lack of fit (R >0.9). For the acid hydrolysis step, the regression model predicted the maximum sugar concentration to be 79.81 g/L at optimum temperature 100°C, time 11.66 min and acid concentration 1.5% w/w. For the enzymatic hydrolysis step, the regression model predicted the maximum sugar concentration to be 93.44 g/L at optimum temperature 58°C, time 55 min and pH of 5.5.Acid hydrolysis, box Behnken design, cocoyam, enzymatic hydrolysis, reducing sugar
Full Article
(Downloads: 64)
Abstract (Viewed: 1)Ethanolic fermentation experiments were carried out using a stirred tank equipped with a Rushton turbine. The data were used to estimate kinetic parameters based on a newly developed kinetics model originated from Herbert's microbial kinetics model. This newly developed model took into account the effects of aeration rate (AR) and stirrer speed (SS). Experiment data i.e. glucose, ethanol and biomass concentrations obtained from different experiment sets were used for kinetics prediction. Assuming a perfectly-stirred condition, the kinetic parameters were initially estimated through solving Herbert's model equations. These estimated kinetic parameters were then incorporated in a Computational Fluid Dynamics (CFD) model but the simulation results did not agree well with the experiment findings. Based on the proposed CFD model, the kinetic parameters were corrected. The correction factors were expressed as functions of AR and SS. This analysis highlighted the need to estimate kinetic parameters based on CFD simulation because it is able to account for the spatial variation in a reactor. A sensitivity analysis of the kinetic parameters using the coupled CFD-fermentation kinetic model was carried out to further understand the influence of each set of kinetic parameters on the model prediction. It was found that the sensitivities of the kinetic parameters varied with the concentrations of glucose, ethanol and biomass. Bioreactor, CFD, ethanol, fermentation, kinetics, Rushton turbine
Full Article
(Downloads: 43)
Abstract (Viewed: 1)A study of the development of spontaneous tumours in dogs gives many benefits in oncology research due to the similarity between dog and human cancer in terms of epidemiologic, biologic and clinical features. There is evidence that the complement component 5 anaphylatoxin (C5a) and its receptor are involved in the development of many types of tumour due to its inflammatory properties. The purpose of this study was to determine the expression of C5a on several types of canine spontaneous tumour i.e. mammary tumour, lung tumour, testicular tumour and melanoma. The expression of C5a in these tumours was compared with normal tissue from the breasts, lungs, testes and skin. The total of eight post-mortem canine tissues were collected from University Veterinary Hospital (UVH), University Putra Malaysia and stored in a preservative solution (RNAlater) to keep the RNA from degrading. The RNA was extracted using the Qiagen RNA Extraction Kit and a cDNA synthesis was carried out using a one-step PCR kit (Promega, USA). The expression of C5a was determined using reverse transcriptase PCR (RT-PCR) and Quantitative real-time PCR (qPCR) techniques. The results showed that all types of tumour gave higher expression of C5a compared to normal tissue. This means that the CT value for the tumours was below 30 cycles except for melanoma and the expression of C5a of normal tissues was above 30 cycles. This finding suggests that C5a and its receptor may be involved in the development of tumours in dogs and can be used as a tumour biomarker for both animals and humans in the future. Nevertheless, further studies investigating the mechanisms of C5a and its receptor in canine spontaneous tumour are necessary.Canine spontaneous tumour, C5a, C5a receptor
Full Article
(Downloads: 45)
Abstract (Viewed: )The Group Runs (GR) and Side Sensitive Group Runs (SSGR) control charts are the improvement of the synthetic chart without and with side sensitivity. Both the SSGR and GR charts are effective for detecting small to moderate process mean shifts. The performances of the SSGR and GR charts, in terms of the average time to signal (ATS), are compared in this paper. In this comparative study, the Monte Carlo simulation approach by means of the Statistical Analysis System (SAS) software is used to compute the ATS values for the GR and SSGR charts. The results revealed that the SSGR chart's performance is better than that of the GR chart for all levels of mean shifts.Average time to signal, GR chart, SSGR chart
Full Article
(Downloads: 43)
Abstract (Viewed: 6)The bit-plane feature extraction approach has lately been introduced for face and palm-print recognition. This approach decomposes an 8-bit grey level image into eight groups of bit layers. The assumption of this approach is that the highest order of a bit-plane decomposition, which has the most significant bits of all pixels, contains the most biometric features. Nonetheless, most research has identified bit-plane images illustratively. Hence, in order to endorse the assumption, we performed an analysis on face and palm-print images to identify the bit-plane that contributes most significantly to the recognition performance. Analysis was done based on Principal Component Analysis (PCA). The first principal component was applied as it is defined for the largest possible variance of the data. Next, Euclidean distance was calculated for matching performance. It was observed that bit-plane 6 and 7 contributed significantly to recognition performance.Bit-plane, Principal Component Analysis, face recognition, palm-print recognition
Full Article
(Downloads: 80)
Abstract (Viewed: 8)Naive Bayes (NB) is a simple but powerful tool for data classification. It is widely used in classification due to the simplicity of its structure and its capability to produce surprisingly good results for classification. However, the independence assumption among the features is not practical in real datasets. Attempts have been made to improve the Naive Bayes by introducing links or dependent relationships between the features such as the Tree Augmented Naive Bayes (TAN). In this study, we show the accuracy of a General Bayesian Network (GBN) used with the Hill-Climbing learning method, which does not impose any restrictions on the structure and better represents the dataset. We also show that it gives equivalent performances or even outperforms Naive Bayes and TAN in most of the data classification.Naive Bayes, classification, Tree Augmented Naive Bayes, General Bayesian Network
Full Article
(Downloads: 71)
Abstract (Viewed: 3)Rising global temperatures have threatened the operating conditions of Batang Padang hydropower reservoir system, Malaysia. It is therefore crucial to analyze how such changes in temperature and precipitation will affect water availability in the reservoir in the coming decades. Thus, to predict future climate data, including daily precipitation, and minimum and maximum temperature, a statistical weather generator (LARS-WG) is used as a downscaling model. Observed climate data (1984-2012) were employed to calibrate and validate the model, and to predict future climate data based on SRES A1B, A2, and B1 scenarios simulated by the General Circulation Model's (GCMs) outputs in 50 years. The results show that minimum and maximum temperatures will increase around 0.3-0.7 °C. Moreover, it is expected that precipitation will be lower in most months. These parameters greatly influence water availability and elevation in the reservoir, which are key factors in hydropower generation potential. In the absence of a suitable strategy for the operation of the hydropower reservoir, which does not consider the effects of climate change, this research could help managers to modify their operation strategy and mitigate such effects.Climate change, precipitation, temperature, global climate models, weather generator, statistical downscaling, LARS-WG
Full Article
(Downloads: 60)
Abstract (Viewed: 6)Oncocytomas are rare head and neck neoplasms that occur most commonly in the parotid salivary gland. Birt-Hogg-Dube syndrome is a rare inherited genodermatosis manifested by a group of cutaneous lesions, in association with several renal and lung pathology, parotid oncocytoma, thyroid and colonic tumours. Here we report on the case of a patient who presented with parotid oncocytoma in association with skin lesions, multinodular goitre and uterine leiomyoma. This array of lesions suggested the possibility of Birt-Hogg-Dubé syndrome. 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (18F FDG PET/CT) was used to evaluate head and neck malignancies, including salivary gland tumours. In this report, we highlight a case of bilateral parotid oncocytoma with suspected BirtHogg-Dubé syndrome that showed increased FDG uptake in a PET-CT study. This marked FDG avidity in a benign parotid oncocytoma, adding to the list of common pitfalls related to the parotid glands during a FDG PET-CT study.Oncocytoma, parotid gland, 18F FDG PET CT (18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography), BHD (Birt-Hogg-Dubé Syndrome)

Online Submission| Call for Papers| Special Issues| Subscribe Journals| Resources| Site Map| 608695