Download Latest Complete Journal - JST Vol. 27 (4) Oct. 2019
Foreword by the Chief Executive Editor
No.ArticlesDownloads
1
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(Downloads: 58)
Abstract (Viewed: 4)The presence of imaging technologies in Malaysia needs to be supported by homegrown research to optimize and tailor their usage for local benefits. Research done elsewhere may not be applicable to local situations. This study investigates the contribution of researches by Malaysian academicians and service providers to the field of medical imaging, as evident in the Malaysian Citation index (MyCite) database. Bibliometric and thematic analyses were performed on publications featured in the database from 2006 to 2016. The bibliometric analysis provided information on the affiliation of the authors, their professional backgrounds, types of studies, and the journals involved while the thematic analysis identified the themes and sub-themes of identified articles. The study found that Malaysians contributed 54.1% of the publications, followed by non-Malaysians (41.8%) and collaboration authors (4.1%). Researchers were mostly from university-based and hospital university-based institutions. The thematic analysis presented that 42.9% of articles were classified under clinical themes. The results also suggested that the current trends of research in medical imaging are focused on topics involving clinical and modality, and only a few patient-centered researches. This is an indication that more researches that are relevant to local practices and needs are required as this will strengthen the medical imaging practice in the country.Academicians, bibliometric study, medical imaging, MyCite, Scopus, service providers, thematic analysis, web of science
2
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(Downloads: 32)
Abstract (Viewed: 3)Aggression is one of the most common Paediatric Psychiatric emergency problems presented in healthcare services with major public health impacts. The aim of this review is to determine the psychosocial predictors of adolescent aggression. Systematic review on observational study designs were conducted. Recent five years English published journal articles (2014-2018) were searched in three databases (Science Direct, PubMed and EBSCO) from April 2018 until May 2018. The final 15 articles (seven prospective cohort, eight cross-sectional studies) were included in the systematic review. Psychological predictors were mainly on the personality traits and emotional problems experienced by the adolescents including callous-unemotional traits, hostility, anger, and low empathy. Self-control was found to be protective against adolescent aggression. Social predictors that contribute to the aggression among adolescents according to the highest reported number of articles were peer influence, followed by school climate, substance use, neighbourhood influence, family, and parent factors. In conclusion, psychosocial predictors of adolescent aggression include both Psychological Factors; mainly personality traits and emotional problems, and Social Factors; mainly peer influence and substance use. This warrants for more holistic approach in dealing with aggressive adolescents that can be applied in more targeted and focused intervention strategy deliveries.Adolescent, aggression, predictors, psychosocial
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(Downloads: 26)
Abstract (Viewed: 3)The global Tuberculosis epidemic (TB) poses a significant public health threat. While the consequences of TB treatment interruption are indisputable, the knowledge about the timing and prognostic factors of TB treatment interruption is fundamental. Despite a considerable amount of evaluation, the timing and prognostic factors of TB treatment interruption have been inconsistently identified from one study to another. Therefore, this study aimed to examine the evidence obtained from published literature on the timing and prognostic factors of TB treatment interruption at different points of the treatment course. In this review, three databases namely Pubmed, Scopus, and Science Direct were used to identify articles published from January 2003 to February 2018. This was based on the inclusion criteria and keywords including ‘default’, ‘survival time’, ‘tuberculosis’, and ‘treatment interruption’. The nine selected studies were prospective and retrospective cohort studies conducted in developing countries. The diversity of the study’s participants and TB treatment interruption definition were allowed, thus delineating a heterogeneous finding. This review suggests that the interruption predominantly occurred during the maintenance phase of treatment course. Despite the finding, a considerable gap in understanding the prognostic factors at different time points of TB treatment interruption was elicited. The heterogeneity across the studies may limit the inferences and warrant further evaluation. In essence, the time-related information should be integrated into framing impactful public health strategy, while a vigorous attempt on the evaluation of the cognitive, behavioural and psychosocial aspects may be beneficial. Default, survival time, treatment interruption, tuberculosis
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(Downloads: 32)
Abstract (Viewed: 1)Failure of pancreas can cause uncontrolled blood glucose levels in the body. This research focuses on type 1 diabetes patients who depend on external insulin injection. The Hovorka model was used as the mathematical model in the development of control algorithm for artificial pancreas. However, the model showed a lack of interaction on selected parameters and variables in its glucose-insulin dynamic system. An improvement on the Hovorka equations was done, but no work was carried out to simulate the proposed equations. The objectives of this study are to simulate the modified Hovorka equations using MATLAB and to compare the simulation results between the reference and modified ones. This study showed better interaction among all variables and parameters on its glucose-insulin dynamic system using the modified equations compared to the original equations. The lower administered amount of insulin, Ut at 16.7mU/min and 20mU/min could regulate the blood glucose level at normoglycemic condition throughout the study.Artificial pancreas, control algorithm, hovorka model, MATLAB simulation, type 1 diabetes
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(Downloads: 19)
Abstract (Viewed: 1)This study aimed to evaluate surface roughness (SR) changes with surface treatments and shear bond strength (SBS) of two prefabricated and one laboratory-made composite veneer systems. The prefabricated groups, Edelweiss (EDL) and Componeer (CMP) while, SR Nexco (NEX) was a laboratory-made group. A total of hundred twenty samples, comprising 40 samples for each group were divided into four subgroups of surface treatment (n=10): (a) no treatment (control), (b) 9% hydrofluoric acid (HF), (c) abrasion with a high-speed diamond bur and (d) sandblast with aluminum trioxide (Al2O3) particles. A profilometer was used to evaluate the SR before and after surface treatments applications. Stereo electron microscope was utilized to assess changes occurred on the surface texture of the veneers. For SBS test, the prepared veneer was uploaded over an epoxy resin mould. Two cylindrical adhesive resins were bonded binary and perpendicular over the inner surface of the veneer and tested using Universal Testing Machine (SHIMADZUTM, Japan). Data was analyzed using One-way ANOVA, post-hoc student’s t-test and Duncan test with p<0.05. One-way ANOVA revealed a significant increase in the SR of all veneer groups treated with a diamond bur and Al2O3 sandblast. NEX group showed higher SR (6.52 ± 0.85) followed by EDL (4.59 ± 0.75) and CMP (4.99 ± 0.67) groups. The significant higher SBS was demonstrated by NEX (22.88 ± 5.2 MPa). EDL exhibited higher bond strength (12.3 ± 3.7 MPa) than CMP (11.75 ± 6.5 MPa). A laboratory-made system produced higher SR enhancement with a diamond bur and superior bond strength.Composite veneer systems, surface roughness changes, surface treatments, shear bond strength
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(Downloads: 16)
Abstract (Viewed: 2)Centella asiatica is one of the traditional herbs consumed by many communities due to its wide range of applications such as treating Parkinsonism, promoting memory enhancement, and preventing oxidative stress. This study was conducted to investigate the neuroprotective potential of aqueous C. asiatica extract (CAE) against neurodegeneration induced by chronic stress. Administration of CAE at three different dosages (200 mg/kg/day, 400 mg/ kg/day and 800 mg/kg/day) was conducted for a period of 21 days along with exposure to chronic stress using restrainer and forced swimming regimes. The administration of CAE significantly improved the thickness of dentate gyrus and reduced the amount of neuronal cell death at dentate gyrus and CA3 (p<0.05). Additionally, administration of CAE significantly alleviated the expression c-fos protein (p<0.05). Thus, this study highlighted the neuroprotective effect of CAE against neurodegeneration from chronic stress exposure.Centella asiatica, chronic stress, neuroprotectivity
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(Downloads: 17)
Abstract (Viewed: 1)Malays consist of multi sub-ethnic group believed to have different ancestral origins based on their migrations centuries ago. The DNA profiling for every individual in Malaysia is not recorded, making Malaysia lacking in genetic data of its own citizens. This research aimed to study the geographic-ancestry origin of two Malay sub-ethnic population; Kelantan-Malay and Jawa-Malay by looking into the variation of TPA-25 insertion in each population. It specifically studied on several areas of Peninsular Malaysia in the region of Kelantan, Selangor and Johor as the representative of main areas with high percentage of Kelantan-Malay and Jawa-Malay populations. All the data were obtained from an application of TPA-PCR method, forensic parameter (F-statistic) and survey questionnaire that polled genetically on their ancestry origin in each sub-ethnic population. The research showed that population with high percentage of heterozygous allele (Tt) of TPA-25 insertion was likely to have high possibility of genetic drift occurrence. Jawa-Malay showed the highest percentage of heterozygous allele (Tt) with approximately 48% of the population. The FIS value of Kelantan-Malay and Jawa-Malay populations were recorded positive with the values of 0.678 and 0.366 respectively. Moreover, the FIT value recorded was 0.535 which suggested that these two populations were deficits of heterozygotes.F-statistic, genetic drift, heterozygosity, TPA-25 element
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(Downloads: 16)
Abstract (Viewed: 1)A study was conducted to identify the responses of Aedes albopictus to different diet regime towards the development of juvenile and adult mosquitoes. Fish pellet was selected as standard diet in order to study the effect of diet regime on the development of Ae. Albopictus. Four different diet regimes (1.0 mg, 0.6 mg, 1.0 mg an1.6 mg) were tested on 50 eggs of Ae. Albopictus under laboratory conditions. Juvenile development until adult emergence was observed and recorded. Results indicated that the time taken to mature the mosquitoes was significantly affected by the diet regime. Furthermore, juvenile body size and adult wing size of Ae. Albopictus were found to be greatly affected by diet regime exposed during juvenile stages. In summary, an increase of diet regime resulted in the decrease of developmental time and an increase in juvenile body size and adult wing size.Aedes, Ae. Albopictus, diet, juvenile size, wing size
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(Downloads: 18)
Abstract (Viewed: 1)Presently the radiological examination is widely used for the assessment of in vivo bone condition. In some clinical problems such as diagnosis of the point of union of a fracture; the manual assessment is used along with radiological examination. Uncertainty regarding the significance of the radiographic and clinical findings may result in unnecessary long immobilization periods which can produce discomfort for the patient, as well as possible stiffness of the joints and sometimes permanent loss of mobility specially in older population. This paper deals with the in vivo analysis of bones by Acousto-Ultrasonic technique. The fracture was created through surgery on one of the limbs of rabbit and healing process was monitored through acousto-ultrasonic technique. A new index known as bone healing index was defined to calculate the end point of healing. In most of the cases, the bone healing index value was found to be 0.80, indicating that 80 % of the strength could only be restored at the completion of healing process.Acousto-ultrasonic, bone healing index, fracture healing, stress wave factor
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(Downloads: 15)
Abstract (Viewed: 1)The zebrafish (Danio rerio) has become a prevailing vertebrate model for developmental biology studies due to its ease of care, rapid embryogenesis stages development and translucent embryos. In this studies, ATM Kinase and MRN complex role as DNA damage response proteins during embryogenesis was examined by using specific MRN complex (Mirin) and ATM Kinase inhibitors (Ku60019 and Ku55933). To create DNA lesions in zebrafish, embryos at mid-blastula transition (MBT) stage were exposed to inhibitors (Mirin, Ku60019 or Ku55933) and later exposed to UVC irradiation wavelength of between 100 to 280 nm. Hatching but with visible physical deformation was observed for embryos treated with Mirin, Ku60019 or Ku55933 and UVC exposure at concentration of 3µM, 1.5 nM and 3nM or lower, respectively up to 72 hours-post fertilisation (hpf). On the other hand, no deformities were observed for all control as well as mock treated embryos. This study confirmed that DNA damage response proteins are crucial during embryo development to prevent undesired abnormal biological development. Thus, it is proven that protein inhibitors are a cheaper alternative in valuating specific protein roles during embryogenesis compared to both genomic and transcription modification tools.ATM Kinase, Danio rerio, DNA damage, MRN complex, zebrafish
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(Downloads: 16)
Abstract (Viewed: 1)The human hexokinase isoform II (HKII) is one of the important enzymes for dengue virus (DENV) replication and thus has been suggested as a potential therapeutic target for DENV drug development. In this work, compounds were identified using Ultrafast Shape Recognition with CREDO Atom Types (USRCAT) by utilizing both HKII’s substrate and product; alpha-D-glucose (GLC) and beta-D-glucose-6-phosphate (BG6), as well as a known HKII’s inhibitor, 2-deoxyglucose (2DG), as the query molecules. The analogues of the three query molecules were subsequently docked against the HKII’s crystal structure (PDB ID: 2NZT) by using Auto Dock 4 program on Chain B, where the active sites and strong bonds were located. Among the top-ranked compounds, Compound 4 (ZINC26898487), which was the most similar to 2DG, showed the best binding energy (-7.63 kcal/mol) and contained two H bonds. Compound 9 (ZINC16930948), an analogue of GLC emerged as the best inhibitor candidate because it had six H bonds. Similarly, among the molecules similar to BG6, Compound 14 (ZINC4403351) had been suggested as a potential inhibitor because it contained four strong H bonds. All compounds were predicted to be non-toxic, based on Toxicity Estimation Software Tool (TEST) analysis. By providing these valuable findings, this study has paved the way for the discovery of compounds that should be further tested for the development of anti-dengue drugs.2-deoxyglucose, alpha-D-glucose, beta-D-glucose-6-phosphate, Human Hexokinase II (HK2), ligand-based screening, structure-based screening, toxicity test
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(Downloads: 18)
Abstract (Viewed: 1)Machine simulation of human reading has caught the attention of computer science researchers since the introduction of digital computers. Character recognition is the process of recognizing either printed or handwritten text from document images and converting it into machine-readable form. Character recognition is successfully implemented for various foreign language scripts like English, Chinese and Latin. In the case of Indian language scripts, the character recognition process is comparatively difficult due to the complex nature of scripts. MODI script - an ancient Indian script, is the shorthand form for the Devanagari script in which Marathi was written. Though at present, the script is not used officially, it has historical importance. MODI character recognition is a very complex task due to its variations in the writing style of individuals, shape similarity of characters and the absence of word stopping symbol in documents. The advances in various machine learning techniques have greatly contributed to the success of various character recognition processes. The proposed work provides an overview of various feature extraction and classification techniques used in the recognition of MODI script till date and also provides evaluation and comparison of these techniques.Classification techniques, feature extraction techniques, handwritten character recognition, MODI script OCR, offline character recognition survey
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(Downloads: 14)
Abstract (Viewed: 1)The high-resolution digital images generated for medical diagnosis produce the extremely large volume of digital data. This necessitates the use of image compression for medical data to be processed, archived and transmitted through a computer network in an efficient way. Due to the criticality in disease diagnostics and legal reasons, biomedical images require lossless compression to prevent permanent loss of image data. Among various approaches to lossless compression of medical images, predictive coding techniques have high coding efficiency and low complexity. Gradient Edge Predictor (GED) used in predictive coding technique for prediction has higher coding efficiency as compared to Median Edge Detector (MED) used in JPEG-LS. GED has lower computational complexity as compared to Gradient Adaptive Predictor (GAP) used in CALIC. GED is a threshold based predictor, however there is no specific method adopted in literature to decide the threshold value for prediction. This paper presents an efficient prediction solution based on predictive coding technique. The main objective of this research work is to develop a Resolution Independent Gradient Edge Predictor (RIGED) technique for choosing an optimal threshold value for GED predictor which will give minimum entropy value irrespective of the type of modality and resolution of the medical images. The empirical experimentation and analysis gave percentage improvement of the proposed model as 32.4% over MED and percentage difference between high complexity GAP and proposed predictor as 0.68 % in terms of entropy for medical image dataset of different modalities having different resolution.Lossless image compression, medical imaging, predictive coding, predictor, resolution independent gradient edge detection
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(Downloads: 19)
Abstract (Viewed: 1)Manual fruits and vegetables detection become easy when it is done in small amount, but it is a tedious process and more labor is required when gigantic amount is considered. So, automatic detection of these comes into usage. This study took the images of fruits and vegetables as input to the very first stage of processing from where detection was done. The entire process constituted three stages: Background subtraction, extraction of color as well as texture features, and then classification. Background subtraction was performed using k mean clustering technique. Color features were identified using statistical features. To identify texture features Histogram of Oriented Gradient (HOG), Local Binary Pattern (LBP) and Gray Level Co-occurrence Matrix (GLOM) were used. For training and classification, Support Vector Machine (SVM) classifier had been used and performance of this classifier had been compared with K Nearest Neighbor (KNN) classifier. After comparing the results, it shows that accuracy of SVM was higher than that of KNN. The accuracy obtained by SVM with quadratic kernel function was 94.3%.Color, gray level co-occurrence matrix, K mean clustering, K nearest neighbor, support vector machine, texture
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(Downloads: 16)
Abstract (Viewed: 1)Low-Density Parity-Check (LDPC) codes are considered among the best error-correcting codes in use today. These codes can be defined by a sparse parity-check matrix H, which has a graphical representation as a Tanner graph. Several studies have shown that the existence of 4-cycles in the Tanner graph affects the performance of LDPC codes. In this paper, we propose a method which allows the construction of 4-cycle-free parity-check matrices. The main principles behind the proposed method are as follows: First, we choose a vector V which consists of wc ones and L-wc zeros, in such a way that the chosen vector allows us to construct a circulant matrix H1 without 4-cycles. Second, we pass this matrix to the proposed algorithm to obtain a set of L-vectors. When any vector taken from this set is appended as a news column in the matrix H1, we obtain an L×(L+1) matrix without 4-cycles. Next, we select those vectors that lead to a circulant matrix H2 without 4-cycles. Finally, we can obtain an L×2L matrix H without 4-cycles by concatenating matrices H1 and H2. Simulation results confirm that the structure of the matrices constructed by the proposed method significantly reduces the encoding complexity. Though the performance of these matrices at higher signal-to-noise-ratios (SNRs) is not as good as those constructed by MacKay’s method, they can be applied to practical communications because of being encoded in linear time with shift registers.4-cycle-free matrices, circulant matrices, LDPC codes, Tanner graph
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(Downloads: 14)
Abstract (Viewed: 2)The use of biometric features, to authenticate users of different applications, is growing rapidly in recent years, according to the high sensitivity of the protected information and the good security that biometric authentication provides. In this study, a method is proposed to measure the similarity between two fingerprint images, using convolutional neural networks, instead of classifying them. Thus, modifying the users that the proposed method can recognize is a matter of adding or removing model images of the users’ fingerprints. The similarity between the fingerprint image and every model image was measured in order to select the user with the highest similarity to the input image as the recognized user, where that similarity measure was compared to a threshold value in order to authenticate that user. The evaluation results of the proposed method, using FVC2002_DB1 and FVC2004_DB1 showed that the proposed method had 99.97% accuracy with 0.035% False Acceptance Rate (FAR) and 0% False Rejection Rate (FRR). Hence, the proposed method has been able to maintain high accuracy while eliminating the vulnerabilities of biometric authentication systems imposed by the use of separate stages for features extraction and similarity measurement.Biometric authentication, convolutional neural networks, fingerprints, machine learning
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(Downloads: 11)
Abstract (Viewed: 2)Referring to the existing model that considers the image boundary as the image background, the model is still not able to produce an optimum detection. This paper is introducing the combination features at the boundary known as boundary components affinity that is capable to produce an optimum measure on the image background. It consists of contrast, spatial location, force interaction and boundary ratio that contribute to a novel boundary connectivity measure. The integrated features are capable to produce clearer background with minimum unwanted foreground patches compared to the ground truth. The extracted boundary features are integrated as the boundary components affinity. These features were used for measuring the image background through its boundary connectivity to obtain the final salient object detection. Using the verified datasets, the performance of the proposed model was measured and compared with the 4 state-of-art models. In addition, the model performance was tested on the close contrast images. The detection performance was compared and analysed based on the precision, recall, true positive rate, false positive rate, F Measure and Mean Absolute Error (MAE). The model had successfully reduced the MAE by maximum of 9.4%.Boundary connectivity, boundary ratio, force interaction
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(Downloads: 15)
Abstract (Viewed: 2)Detection and identification of text in natural scene images pose major challenges: image quality varies as scenes are taken under different conditions (lighting, angle and resolution) and the contained text entities can be in any form (size, style and orientation). In this paper, a robust approach is proposed to localize, extract and recognize scene texts of different sizes, fonts and orientations from images of varying quality. The proposed method consists of the following steps: preprocessing and enhancement of input image using the National Television System Committee (NTSC) color mapping and the contrast enhancement via mean histogram stretching; candidate text regions detection using hybrid adaptive segmentation and fuzzy c-means clustering techniques; a two-stage text extraction from the candidate text regions to filter out false text regions include local character filtering according to a rule-based approach using shape and statistical features and text region filtering via stroke width transform (SWT); and finally, text recognition using Tesseract OCR engine. The proposed method was evaluated using two benchmark datasets: ICDAR2013 and KAIST image datasets. The proposed method effectively dealt with complex scene images containing texts of various font sizes, colors, and orientation; and outperformed state-of-the-art methods, achieving >80% in both precision and recall measures.Adaptive binarization; fuzzy C-means; image enhancement; statistical and geometrical features; text detection; text extraction
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(Downloads: 16)
Abstract (Viewed: 1)Collaborative filtering is the most widespread recommendation system technique deployed in e-commerce services nowadays. It recommends products based on the historical preference of the user. The biggest challenges in these techniques are data sparsity and growing volume of data, specifically in e-commerce sites like movie recommendation. Clustering algorithms are used for scaling up the performance of collaborative filtering in dynamically growing datasets. Most of the existing clustering based recommendation algorithms improve scalability but produce low quality recommendations. This is mainly due to data sparsity, as the user tends to rate very few items from a large number of options available. Moreover, users with a similar taste for a group of items may show different likings for another group of items over a period, i.e.., user’s interest dynamically changes over time. Finding the sub-groups that are more relevant to each other than the entire user-item matrix is more affordable. Since the user’s recent ratings can better represent their interest and preference, a Time Adaptive Collaborative Filtering Method −TACF is proposed, that adopts time to generate a recommendation. Experimental results on the MovieLens dataset show that the proposed system outperforms other state-of-art collaborative filtering algorithms in terms of accuracy and efficiency.Clustering, collaborative filtering, matrix factorization, recommendation system, temporal information, user drifts
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(Downloads: 13)
Abstract (Viewed: 1)A large scale of investigation had been carried out to predict the personality, or in precise, the behaviour of online users through user-generated texts, such as Tweets and status messages. Nevertheless, only a handful of machine learning (ML) studies have applied the personality model to assess criminality behaviour, particularly within the context of Malay social network messages. Based on the concept of sentiment valence, this study annotated a list of Malay Tweets that might be subjected to crime or illicit messages from the stance of Psychoticism trait. Consequently, the supervised-based text classification method was conducted by using Naïve Bayes (NB), Sequential Minimal Optimisation (SMO), and Decision Tree (DT) on Tweets using several features determined via Chi Square (x2). The analyses outcomes signified that SMO outperformed other classifiers insignificantly by achieving 92.85% of accuracy. Based on x2, several swear terms, such as bontot, melancap, and kote, displayed significant correlation with Psychoticism Tweets due to the nature of the trait that has been subjected to criminality behaviour, for instance, aggressive and antisocial attributes. The findings illustrate the possibilities to adapt several personality aspects in order to enhance the effectiveness in detecting illicit social network messages.Machine learning, Malay tweets, personality detection, text mining
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(Downloads: 12)
Abstract (Viewed: 1)Known for its plain and dry content, tajweed learning is often tedious, particularly for children. Our preliminary study confirmed that most of the learners were uninterested to learn tajweed and this fact was agreed by their educators. Currently, technological advancement helps learning enormously and it has been widely utilised, especially for the digital native generation. Therefore, we highlighted the use of augmented reality and gamification as an attempt to attract children to learn tajweed. Based on experience and motivational theory, tajweed augmented reality-based gamification learning model (TARGaLM) was implemented in the tajweed learning. To investigate the effectiveness of the proposed approach in terms of their emotional engagement (enjoyment) potential and learning performance, 198 children constituted four groups participated in the learning activities. TARGaLM successfully gained positive results of autonomy, challenge, points, badges, leader board, progression, immersion, and feedback, which are crucial for enjoyment. In the post-activity interviews, the students mentioned that the proposed approach was interesting. Furthermore, the proposed approach group indicated the highest decrease in articulation errors from the post-test compared to other groups. The use of current technology and approach not only has potential in bringing enjoyment, but also gives a positive impact on the learning outcomes.ANOVA, augmented reality, enjoyment, experience, gamification, motivation, post hoc test, tajweed learning
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(Downloads: 16)
Abstract (Viewed: 2)The sago starch industry is one of the major revenue sources of the Malaysian state of Sarawak. This state is currently among the world’s leading producers of sago starch, exporting more than 40,000 tons every year to different Asian countries. This number is expected to rise since starch production and export value have been increasing 15.0%– 20.0% each year. Sago palm is subjected to various processes to obtain starch from its trunk. During processing, a huge amount of residual solid wastes is generated, such as bark and hampas, and in general, is burned or washed off to nearby streams. Along with the rising sago starch demand, the sago starch industry is now facing waste management problems, which have resulted in environmental pollution and health hazards. These wastes comprise starch, hemicellulose, cellulose, and lignin; hence, can be valorized into feedstock as value-added products. To date, these wastes have been utilized in the production of many materials like adsorbents, sugars, biofuels, nanomaterials, composites, and ceramics. This review article aims to summarize the various methods by which these wastes can be utilized besides to enlighten the major interest on sago hampas and bark.Adsorbent, biofuel, sago bark, sago hampas, waste utilization
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(Downloads: 12)
Abstract (Viewed: 1)A halo tolerant dye decolorizing bacterium Bacillus firmus (TSL9) was isolated from activated textile sludge and identified by 16S rRNA sequencing method. Due to the effect of casein enzymic hydrolysate, and yeast extract, a maximum of 97.23% remazol golden yellow decolorization was manifested by the strain in Luria Bertani medium. Bacterial dye decolorization was insignificant in the aqueous medium, when carbon and nitrogen sources were absent. Plackett-Burman experiments were carried out to screen the significance of factors like beef extract, size of the inoculum and pH on decolorization. Important factors were optimized at various levels by response surface methodology with central composite design. We concluded through model validation that the optimal values of the ingredients required to perform 78.33% decolorization are as follows: beef extract 0.48% (w/v), the size of the inoculum 7.71% (v/v) and pH 6.96. The obtained result specifies that the native bacterium had positive signs to perform effective dye decolorization under derived optimal conditions.16S rRNA, carbon sources, decolorization, nitrogen sources, optimization, remazol golden yellow
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(Downloads: 18)
Abstract (Viewed: 2)The recent drastic decrease in the surface water resources quality has limited water resources managers in Great Karun river basin, southwest of Iran. In this research, the effects of water quality on the satisfaction of different demand sits in Great Karun river basin is modeled and studied by dint of systemic analysis principles based on the actual conditions in the river basin. In addition, different scenarios of water resources quality management are defined and the effect of implementing these scenarios on the demand satisfaction criteria is considered. The achieved results indicate the interactive relationship between quality conditions and performance of the system in demand satisfaction. It means that, the applied operating strategies can improve the demand coverage and reliability of the system only if the quality improvement is considered in extracting those strategies. The considered scenarios are able to improve average monthly demand coverage between 0% and 700% for Abadan city as a critical point within the system. Comparison of different quality management scenarios declares that decreasing the amount of agricultural demands has the most impact on reducing the flow contamination and improving the demand satisfaction throughout the basin, especially in downstream areas like Abadan City. This is due to the wide area of agricultural demands within the basin. Reduction of the agricultural demands causes least contaminated return flows on the one hand, and on the other hand it increases the amount of fresh water of river flows. Great Karun, model calibration, optimum water allocation, water quality modelling, water resources management
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(Downloads: 13)
Abstract (Viewed: 3)This study evaluates the spatiotemporal distribution of aerosol optical thickness (AOT) over Malaysia. The significance of aerosols in regional and global climate change assessment has become a pressing topic in recent climate discussions. Two different approaches are used in measuring AOT; satellite imagery and ground measurement approaches. However, the satellite approach is deemed the best way for monitoring the patterns and transport of aerosols largely due to its extensive spatial coverage and reliable repetitive measurements. The data in this study were obtained from a Sea-viewing Wide Field-of-view Sensor (SeaWiFS), a Multi-angle Imaging Spectroradiometer (MISR), and Moderate Resolution Imaging Spectroradiometer (MODIS) satellite sensors based on a NASA-operated Giovanni portal. Ground-based Aerosol Robotic Network (AERONET) datasets from two sites over the study area were also used. The results show that the highest AOT ground values of 1.93 and 2.00 were recorded in September 2015, at USM station and Kuching station, respectively. Throughout the 15 years of recorded data, the monthly average value of AOT reached its highest values in September, October, and November. In these months, the value of AOT went above 0.40, unlike in other months of the year. Significantly, the results indicate that Malaysian air quality can be evaluated based on AOT values, as these show the variation in optical properties of aerosol.AERONET, AOT, Malaysia, MISR, MODIS, SeaWiFS
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(Downloads: 15)
Abstract (Viewed: 2)A non-coastal cockle farming area such as an estuaries zone might become an alternative for continuous and sustainable cockle supply in the future. The main objective of this research is to determine the growth and mortality rate of Tegillarca granosa (T. granosa) within an estuary area. Three cockle plots were allocated along the estuary area of Kongkong Laut (P1, P2, P3) based on the geographical area, from upper to lower part of estuaries. Cockle monitoring activity was conducted from August to December 2015 for both in-situ water parameters and the cockles’ growth increments. This study shows that within a brackish estuarine environment, the highest cockle growth increment was recorded within the highest water salinity trend area (26.92 ± 4.79 ppt; P2), with a shell increment of 2.70 ± 0.52 mm per month, while the lowest cockle growth increment was recorded within the lowest water salinity trend area (17.65 ± 5.73 ppt; P1) with the shell increment of 2.05 ± 0.86 mm per month. One-way ANOVA shows that there was significant difference (p<0.05) in growth increments among all sites of cockle plots, with significant positive correlation between the salinity level and the cockle’s growth rate (p<0.05, r=0.65). This indicates that salinity level within a brackish environment plays an important role towards cockle’s growth rate. Additionally, high turbidity level for a prolonged period leads to lower cockle survival rates within an area. However, further studies need to be done to look for other environmental factors that may affect cockle growth rate within an estuarine environment.Blood cockle, estuary, growth performance, Kongkong Laut, Tegillarca granosa
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(Downloads: 11)
Abstract (Viewed: 2)Sediment has been widely used as a means for assessing the impact of anthropogenic activities on aquatic environment, with metal pollution being the most well-known threat to aquatic environments. Therefore the aim of this study is to identify and determine metal concentrations, specifically that of copper (Cu), chromium (Cr), cadmium (Cd), iron (Fe), and zinc (Zn) on four sediment cores samples of KongKong Laut Masai Johor. The aqua regia method had been used to analyze Cu, Cr, Cd, Fe and Zn concentrations in sediment samples. Metal concentrations had then been determined through the use of flame atomic absorption spectrometry. The degree of metal contamination in sediment core samples had been determined through using Enrichment Factors (EF) and Geoaccumulation Indices (Igeo). From this study, the mean and standard deviation of metal concentrations in each sediment core sample were shown to be lower than the average shale concentration and lower than both the effects-range low (ERL) and effects-range median (ERM) parameters for aquatic toxicity. This information could be useful, serving as a baseline for evaluating the potential impacts of future development in the area.Enrichment factor, geo-accumulation index, KongKong Laut, metal, pollution, sediment core
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(Downloads: 16)
Abstract (Viewed: 5)The present study aims to determine the level of heavy metals in surface soils and street dust from selected urban and peri-urban locations in the metropolitan city of Kuala Lumpur. Samples were collected from 15 different locations, where Kuala Lumpur City Centre (KLCC) served as the centre point while other locations were located at specific distances from the centre. Surface soils and street dust were collected to detect the level of contamination based on five elements (Zn, Cu, Pb, Cd and Fe). Results indicated that the metal distribution displayed a descending trend as follows: [Fe] > [Zn] > [Pb] > [Cu] > [Cd] and [Fe] > [Zn] > [Cu] > [Pb] > [Cd] in the surface soil and street dust samples, respectively. Geoaccumulation index (Igeo), contamination factor (CF) and pollution load index (PLI) were calculated. Based on the Igeo index, Fe in both samples was found to cause no pollution in all study sites. In surface soils, CF showed all sites were contaminated with Cd in both soil and street dust. In conclusion, the soil sample was polluted with metals while no pollution was found in the street dust in all sites sampled. Further intensive studies are recommended in order to determine other factors which may cause contamination.City centre, heavy metals, peri-urban, street dust, surface soil
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(Downloads: 16)
Abstract (Viewed: 2)Multivariate statistical techniques such as principal component analysis (PCA) and cluster analysis (CA) were applied to water quality parameters in order to interpret complex matrices for better assessment of water quality and environmental status of a watershed. A study was conducted to assess water quality and to establish relationship among water quality parameters in Kelantan River basin. Water quality data was obtained from Department of Environment, (DOE) Malaysia from 2005-2014. Multivariate statistical techniques such as principal component analysis (PCA) and cluster analysis (CA) were applied to 15 water quality parameters in order to interpret complex matrices for better assessment of water quality and environmental status of the watershed. From the results, five PCs were extracted which are collectively accountable for controlling approximately 70% of the watershed’s water quality. Results of cluster analysis indicated that three water quality parameters that included total suspended solids, total solids and turbidity control the water quality of the study area. These parameters were allocated into three clusters based on their similarity. The finding of this study will contribute to existing knowledge of the problems associated with water quality in the basin. This information can be put to use by land use managers and policy makers for future planning and development of the watershed.Cluster analysis, Kelantan, multivariate statistics, principal component analysis, water quality
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(Downloads: 14)
Abstract (Viewed: 2)Urban green space (UGS) in a city is the foundation of natural productivity in an urban structure. It is also known as a natural cooling device that plays a vital role in the city as an urban lung, discharging oxygen to reduce the city heat and as a wall against harmful air pollution. When urbanization happens, UGS, including the gazetted areas, is essentially converted into an artificial surface due to the population’s demand for new development. Therefore, identifying its significance is a must and beneficial to explore. The purpose of this study is to identify the 10 years of UGS change patterns and analyze the UGS loss, particularly in the affected gazetted zone. The study used available aerial imagery data for 2002, 2012, and 2017, and database record of green space. The study had classified UGS by using the Support Vector Machine (SVM) algorithm. The training area was determined by visual interpretation and aided by a land use planning map as reference. The result validity was then determined by kappa coefficient value and producer accuracy. Overall, the study showed that the city had lost its UGS by about 88% and the total gain in built up area was 114%. The loss in UGS size in the city could be compared to a total of 2,843 units of football fields, transformed forever in just 10 years. The uncontrolled development and lack of advanced monitoring mechanism had negatively affected the planning structure of green space in KL. The implementation of advance technology as a new mitigation tool to monitor green space loss in the city could provide a variety of enhanced information that could assist city planners and urban designers to defend decisions in protecting these valuable UGS.Gazetted areas, GIS, high resolution aerial imagery, image segmentation, land cover change, urban green space (UGS)
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Abstract (Viewed: 3)Mixed heat convection inside annular spaces occurs in many engineering technology applications. This study aims to determine the effect of the sinusoidal surface parameters of an outer cylinder, which are represented by variations in the undulation number and amplitude of the wavy surface, on flow structure and thermal fields for different values of the Reynolds number (Re; from 0 to 600) and Rayleigh number (Ra; from 103 to 106). A horizontal annular space bounded by two concentric cylinders contained air with a Prandtl number that equaled 0.7. The sinusoidal surface of the fixed circular outer cylinder was maintained at a constant cold temperature (Tc), whereas the surface of the circular inner cylinder was set at a constant hot temperature (Th) and rotated in counter-clockwise direction at constant angular velocity. Calculations were performed under steady-state conditions. A computational procedure based on the finite volume technique was implemented using the software ANSYS Fluent (version 16.1). Results indicate that the heat transfer from the inner cylinder increased with a rise in the surface amplitudes and undulation numbers with a fixed Re. The average Nusselt number increased with an increase in Ra and reduced when the undulation number increased from one to two. In summary, the heat transfer of the cylinder with the sinusoidal outer surface is better by 7.3% than that of the conventional cylinder.Annular space, concentric cylinders, mixed convection, rotating cylinder, surface amplitude, undulation number
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(Downloads: 12)
Abstract (Viewed: 2)Working in a virtual team presents many challenges. Communication is one of the most important challenges, especially when a virtual team includes members from different countries and background. Virtual project management enables organizations to save on resources such as cost and time. Organizations often struggle with poor communication in their geographically dispersed teams and ineffective communication have been identified as one of the main causes project failure. The aim of this study is to determine the most critical barriers to effective communication in virtual teams. A mixed method of data collection was adopted using semi structured interview with communication and construction experts, and questionnaire approach with construction companies that are G5-G7 rated. Data were analyzed using pareto and exploratory factor analysis for the development of a strategy for enhancement of communication management within virtual teams. The result shows that lack of trust and misunderstanding are the most important barrier to communication within virtual teams. However, managing communication process has been identified to have more impact on the barriers, while planning communication has the least impact. Establishing rule for response and changing focus from individual to group were identified as the two most important factors required in order to sustain trust within virtual teams.Communication, virtual project management, virtual team
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(Downloads: 14)
Abstract (Viewed: 2)External risk factors influence the project objectives, especially project scheduling. Some risks may occur frequently but have low impact, while others may have both high frequency and high severity. The linkage between risk frequency and impact needs to be assessed to understand the significance of a risk variable. This study was aimed to examine the significance of risk related to the probability of occurrence and the magnitude of impact on the project schedule. The study focused on external risk factors (sociopolitical, government policy, natural disasters, and monetary). Survey questionnaires were sent to 20 targeted contractor companies in the area of Aceh Province, Indonesia with a response rate of (60%). Using Risk Importance Index (RII), the significant risk variables that hindered the achievement of project achievement in Period I have been identified as follows: cultural conditions and local customs near project site (K4), social issues/surrounding environment (K5), increased fuel prices (L4), uncertain weather conditions (M1). In addition, the emergence of L4 variable in Period I was due to temporary security conditions, while in Period II due to the conditions of supply and demand. The results of this study are intended to contribute to the application of risk to practitioners and governments.Construction project, contractor, external risk, project schedule, risk importance
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(Downloads: 10)
Abstract (Viewed: 1)Nitrobenzene (NB) is a nitroaromatic compound possessing explosive properties. Timely detection of this compound will prevent emotional and financial losses to mankind. As direct sensors are not available, a parametric modeling approach is developed using the coated Quartz Crystal Microbalance (QCM). These sensors are mass sensitive and can measure changes in mass in few micrograms. When the sensing electrode is deposited with a chemically sensitive coating, adsorption of gas molecules occurs at the surface when exposed to a gas. This results in increased deposited mass and decrease in resonant frequency. This increase in mass is proportional to the gas concentration. A parametric model is derived for coated QCM using the Diffusion reaction model and kinetic analysis to estimate the gas concentration. When the concentration is beyond permissible limits, precautionary measures can be taken to prevent heavy losses. The parameters of sensing layer density and thickness, resonant frequency of quartz, exposition time were used to develop the model along with standard crystal parameters. The developed parametric model was validated experimentally using an AT cut 10MHz crystal, deposited with a sensitive coating of Polyaniline, Tungsten Oxide, Palladium and Dimethyl Sulfoxide. The GAMRY Electrochemical Quartz Crystal Microbalance (EQCM) was used for acquiring and analyzing the response of the QCM for NB sensing. The model was validated analytically with the Extended Butterworth Van Dyke (EBVD) model, rearranged for gas concentration determination. The model performed with an accuracy of 74% for concentrations higher than 300 ppb.Adsorption, chemically sensitive layer, diffusion, kinetic analysis, nitroaromatic explosive, nitrobenzene, parametric model, resonant frequency
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Abstract (Viewed: 1)Heat exchangers are used in many industries and power generation applications. The performance of heat exchangers depends on the operating parameters and the types of flow. The sudden pressure drop is one of the major problems encountered in heat exchanger, and this would significantly affect the efficiency and the overall heat transfer coefficient of the heat exchanger. Therefore, this study is aimed at investigating and analyzing the effects of operating parameters that cause pressure fluctuation and affect the overall heat transfer coefficient. Experimental study was carried out for two types of flows: co-current and counter concurrent flows. Comparisons of the overall heat transfer coefficients between shell and tube and spiral coil heat exchangers were made. It was observed that mass flow rate affected the overall heat transfer coefficient. Besides, the counter current flow was more efficient compared to the co-current flow with enhanced overall heat transfer coefficient. The maximum overall heat transfer coefficient for spiral coil heat exchanger counter flow was 2702.78 W/m2.K, showing a higher heat transfer efficiency when compared to the shell and tube heat exchanger. Moreover, the spiral coil heat exchanger occupied less space as opposed to the shell and tube heat exchanger.Co-current, counter current, overall heat transfer coefficient, pressure drop, shell and tube heat exchanger, spiral coil heat exchanger
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(Downloads: 14)
Abstract (Viewed: 1)This current study represents a numerical computational fluid dynamics (CFD) study of Glass beads-water slurry flow and aims for the optimization of various flow parameters adopting a new approach combining Taguchi’s method and genetic algorithm (GA) for a smooth and better flow of the slurry. Three flow parameters viz. inlet mean velocity (Vm), volume fraction (Cvf) and particle size (Dp) with three levels were considered for the simulation and two responses vs. particle flow velocity (Vf) and pressure drop (ΔPL) were analysed to achieve a better understanding of the complex multiphase Glass-beads Water Slurry flow. Taguchi decision making technique and Genetic algorithm were exploited in order to optimize the particle flow velocity and pressure drop. A mathematical model was developed in order to forecast the responses analytically. Analysis of variance (ANOVA) was selected for finding the contribution of the selected flow parameters on particle flow velocity and pressure drop. The designed experiments were simulated numerically using analysis systems (ANSYS) software package by adopting Eulerian two-phase approach along with RNG K-ε model. Finally the optimized responses along with percentage reduction in pressure drop were reported and validated with the experimental data. This study optimized the pressure drop and particle flow velocity for three different input factors which would be helpful for the slurry-transporting industries, Oil and Gas industries and thermal power plants for optimal pipe design as well as to initiate a smooth slurry flow through horizontal pipeline.ANOVA, concentration distribution, genetic algorithm, pressure drop, regression analysis, slurry flow, Taguchi’s method, velocity distribution
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Abstract (Viewed: 1)Eco-design is an advanced method for product and process to achieve sustainability. For sustainability, manufacturing companies should contemplate and encourage eco-design products and processes. Brass-ware manufacturing involved excessive energy consumption and material wastage, which makes the process unsustainable. The purpose of this study is to develop a systematic-innovation methodology for the eco-design process in brass-ware manufacturing by considering the eco-efficiency parameters based on Quality Function Deployment (QFD) approach and Theory of Inventive Problem Solving (TRIZ) tools. QFD is used for translating customers’ requirements into manufacturing standards. TRIZ laws are used to solve the eco-contradiction matrix, which finds solutions to make the process eco-efficient and sustainable. On solving the eco-contradiction matrix generic solution is obtained such as ‘31 Porous Materials’, ‘15 Dynamics’, ‘10 Preliminary Action’, and ‘40 Composite Material’. The application of the proposed method has been demonstrated by a case study of the brass-ware manufacturing process in India. This method may be useful and used as a potent tool for design engineers to invent new, robust, and eco-friendly products and processes.Eco-design, eco-innovation, quality function deployment, theory of inventive problem solving
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(Downloads: 9)
Abstract (Viewed: 1)Oil content removal by Cassia surattensis seeds was deliberated in a batch. Significance of the current study is to treat water that is associated with oil. The water contains high organic materials, which is completely dissolved. Previous processors had problems such as low efficiency and costly. Cassia surattensis seed was branded by using Fourier transform infrared spectroscopy. Contact time, dose quantity and pH value were examined for oil content elimination in produced water (PW). A declaration of pH value from 2.0–9.0 was accompanied by an improved amount in oil that was adsorbed. The high oil content removal was 79.4% at pH 2, 120 min and 2 g of Cassia surattensis seeds. The equilibrium adsorption values were obtained and studied by using the Freundlich and Langmuir models. The Freundlich model was found to obtain the finest relation with the tested values. The greatest adsorption capacity of the oil content was 12.18 mg/g. The outcome of the statistical model showed successful results, whereby the F-value was 51.9 and p-value was 0. The present study results proposed that Cassia surattensis seeds may be used as a low-cost adsorbent to eliminate oil content in produced water.Adsorption, natural adsorbent, produced water, water treatment
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(Downloads: 15)
Abstract (Viewed: 2)Torrefaction is a thermal process to convert biomass into a coal-like material, which has better fuel characteristics than the original biomass. Torrefied biomass has more energy density and hydrophobic which is superior quality for handling and storage. The objective of this research was to develop a simulation model of the torrefied pelletization process from empty fruit bunch (EFB). The process was simulated using ASPEN Plus. Optimization involved a selection of the model option that produced the maximum mass yield and minimum energy requirement, with a converged base case simulation as a starting point. Torrefied biomass pellet offered coal-like properties such as high heating value, brittle, high bulk energy density and more hydrophobic. These properties could potentially avoid costly power plant modifications. On the other hand, Malaysia has issued National Biomass Strategy 2020 with target to solve the problem of under-utilized biomass in this country. Base model was based on previous study. For optimization of mass yield and overall energy consumption, six model options of design configurations were analysed. Design model 0 was used as the base model. For design model 1, flue gas from combustion reactor was channelled to torrefaction reactor. For design model 2, flue gas from combustion reactor was split to dryer and torrefaction reactor. For design model 3, combustion reactor was removed. For design model 4, flue gas was channelled to dryer reactor without combustion reactor. For design model 5, flue gas separator after dryer was removed. Out of five options, results were tabulated for the optimum one. The results showed that the highest mass yield was achieved by simulation Model 5 at 90.76 % and lowest energy requirement was achieved by simulation Model 4 at 411.336 kW. Optimization result meanwhile had shown that Model 4 was selected because it gave the maximum profitability of RM 72834.45 by considering the yield and the energy consumption simultaneously.ASPEN Plus, empty fruit bunch (EFB), optimization, torrefaction and pelletization (TOP)
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(Downloads: 14)
Abstract (Viewed: 1)Accurate measurement of spatial distribution of temperature and other micro-climatic parameters inside a greenhouse is important for their monitoring and control. To that end, suitable sensors in adequate number need to be appropriately distributed inside the greenhouse. Two new techniques, namely, Equal Temperature-Step (ETS) and Equal Segment-Area (ESA) techniques are proposed here for the selection of an optimal number of temperature sensors and their locations in a greenhouse with the objective of minimizing the Average Error (AVE), Root Mean Square Error (RMSE) and Maximum Temperature Error (MTE). These techniques were compared with TAE technique, reported earlier. Computational algorithms for the proposed techniques are also presented. Mathematical model of a typical temperature profile along the length of greenhouse has been developed and used for evaluation of the performance. The study shows that the minima of the three errors did not occur simultaneously for any number and locations of the sensors for TAE method. For ETS and ESA methods, the minima of all the three errors occured for the same number and locations of sensors and a smaller number of sensors needed to be used from error consideration. However, reduction in the errors with increase in the number of sensors was steeper for ETS technique as compared to ESA technique, thereby making ETS the best technique. This work can be readily adopted for the measurement of spatial distribution of any other parameter in a greenhouse.Average error, intelligent greenhouse, maximum error, profile, root mean square error, spatial distribution, wireless sensor network
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(Downloads: 12)
Abstract (Viewed: 1)This paper presents two gear driven wind turbine generators (WTG) feeding a single three level grid connected NPC inverter. Each component of WTG is made up of wind turbine, 2-mass gear drive, permanent magnet synchronous generator (PMSG), AC-DC-AC power converter. A simple advanced hill climbs search (AHCS) maximum power point tracking algorithm that uses the mechanical power from the Wind turbine was developed to generate proper duty cycle for the control of single stage DC/DC boost converter. The DC link voltages are series interconnected and fed to a sinusoidal pulse width modulation (SPWM) controlled high power inverter. The complete model is simulated using MATLAB/ SIMULINK software under fixed and fluctuating wind speed conditions. Simulation results have shown that WECs exhibit variability in their output power as a result of changes in their prime movers (wind speed).Advanced hill climb search (AHCS), DC-DC boost converter, neutral point clamped inverter, total harmonic distortion (THD), wind energy conversion system, wind turbine generator
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(Downloads: 13)
Abstract (Viewed: 2)Silver nanoparticles (Ag0) impregnated into bacterial cellulose (BC) by immersion in an antimicrobial concentration of 1,700 µg/ml (10 mM) AgNO3 solution were used to synthesize silver nanoparticle-impregnated bacterial cellulose (Ag0BC) composites. Ag0BC incorporated into insertable footpad was developed for reduction of foot odor associated with pitted keratolysis, primarily caused by Micrococcus sedentarius. A scanning electron microscope (SEM) revealed the porous structure of Ag0BC fibers impregnated with Ag0 particles. The antibacterial activity of Ag0BC for Micrococcus sedentarius revealed a growth inhibition zone of 30 mm in diameter by disc diffusion method. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of AgNO3 solution against Micrococcus sedentarius were 0.42 µg/ml and 0.83 µg/ml, respectively. The effficiency of an Ag0BC footpad applied to shoe samples was measured via total bacterial counts over a time period of 14 days. As expected, the percentage of surviving bacteria in three different types of shoe samples was gradually decreased in the period beginning on the 2nd day. Moreover, no bacterial growth was found in any shoe sample within 8–14 days. However, the cytotoxicity of 5.31–1,700 µg/ml AgNO3 concentrations revealed 50% growth inhibition (IC50) on human dermal fibroblast cells by resazurin microplate assay (REMA). Thus, it can be concluded that Ag0BC, synthesized with lower doses of AgNO3 concentration (< 1,700 µg/ml), may be able to apply in Ag0BC footpad production for inhibition of Micrococcus sedentarius growth and prevention of foot odour in different types of footwears.Bacterial cellulose, foot odour, footpad, micrococcus sedentarius, silver nanoparticles
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(Downloads: 12)
Abstract (Viewed: 1)There has been a rapid turnaround from meat consumption to fish consumption in Nigeria over the last few years. As at 2013, the rate of fish consumption in Nigeria has risen to 2.6 million tonnes with a per capita consumption of 13.5 kg. Heavy metals bio-accumulate in fishes especially when the water body is polluted. Hence, humans are at risk of being affected by these metals via the consumption of contaminated fish, fish products and other aquatic foods captured from a contaminated river for this reason, there is need to monitor the level of heavy metal concentration in water bodies where they are caught. Analyses were done on fourteen (14) elements (Fe, Ni, Cr ,Cu , Mn, As, Zn,Ca, Ti, Se,Rb,K, Sr, Co) in three different fish species were analysed using Energy Dispersive X-ray florescence (EDXRF). The result showed that the mean values of Cr, Mn, Fe, Ni, Cu, Zn and As were all Higher than the recommended FAO/WHO standards. Generally, metal concentration in the gills is higher than that of the muscles for each species except Zn, Se and Fe in which is higher in the muscle for Tilapia fish and Fe, K and Rb which is higher in the muscle for Catfish. The target hazard quotient (THQ) of each metal through consumption of fishes from Oluwa river for both adults and children increased in the following order: Fe < Ni < Cr < Cu < Mn < As.Element, hazard index, target hazard quotient, X-Ray fluorescence
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Abstract (Viewed: 1)Fatty acid profile of Canarium schweinfurthii mesocarp oil was determined by GC-MS. Sulphonated fatliquor was synthesized from the oil and characterized by FT-IR, 1H NMR, 13C NMR, and DSC. The fatliquor was applied onto light leather in the processing of leather shoe upper and physical tests carried out on the fixed leather. The sulphonated C. schweinfurthii mesocarp oil had good characteristics as a leather fatliquor as shown by the physical and strength properties of the fatliquored leather. In addition, a significantly opened up structure of the leather treated with the prepared sulphonated oil was observed as indicated from the Scanning Electron Microscopy (SEM) images. The features of the processed trial leathers were comparable with similar leather made with commercially available fatliquor.Canarium schweinfurthii, characterisation, fatliquor, leather, oil, sulphonated
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(Downloads: 11)
Abstract (Viewed: 1)This work describes the application of three different neural network, (i) Back propagation neural network (BPNN), (ii) Layer Recurrent Neural Network (LRNN) and (iii) Radial Basis Fewer Network (RBFN) model, to predict runoff. Here, two scenarios were considered for developing the models. Scenario 1 exclusive of evapotranspiration and Scenario 2 with evapotranspiration are considered for experiencing the impact on runoff. Performance indicators entailed Scenario 2 performed best as compared to Scenario 1. Two watersheds Loisingha, and Saintala were considered for study. In Loisingha watershed, LRNN performed best with architecture 4-3-1 following tangential sigmoid transfer function. At Saintala, both LRNN and BPNN performed in parallel with small deviation of prediction and LRNN performed best among three networks with model architecture 4-2-1 using Log-sig transfer function for predicting runoff.Evapotranspiration, neural network, precipitation, runoff, temperature, watershed
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(Downloads: 12)
Abstract (Viewed: 3)Livestock operation activities such as cleaning operation, feeding, milking and manure disposal are potential sources of contaminants into nearby surface and groundwater. In this study, the number of wastes generated from a cattle farm in Ladang 16 UPM, Serdang Selangor was estimated. Two monitoring wells were constructed at the site for groundwater quality monitoring assessment. The concentration of pollutants such as Potassium, Nitrate, and Copper was used in the simulation as an initial waste state. The simulation was conducted using Visual MODFLOW Software to predict the contaminants in groundwater. The aim was to predict the concentration of the pollutants distributed in groundwater and surface water sources in 365 days. Results of MODFLOW simulation showed that the flow of groundwater was in the direction towards the pond. The concentrations of Potassium, Nitrate, and Copper were predicted to accumulate in the groundwater to the pond within a year but the values were still below the drinking water standard. The groundwater contaminants could be due to seepage from the manure storage basin through subsoil into the shallow aquifer. Cattle farm, groundwater contaminants, monitoring well, visual MODFLOW
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(Downloads: 10)
Abstract (Viewed: 1)The Eastern Indian Ocean has complex dynamic circulation systems affected by monsoonal wind circulation and climate variation. This research aimed to investigate the spatial and temporal variability of the sea level, and the geostrophic currents in the Eastern Indian Ocean using altimeter data. We used daily time series sea level anomaly data from 2004- 2016 and applied time-series analysis of EOF. The highest four-modes were adopted. Both sea level anomaly and geostrophic zonal component had the sum of explained variance with 79.68% and 35.65%, respectively. The spatial pattern of the sea level anomaly showed dominant variability spread around the west coast of Sumatra and south coast of Java with positive and negative anomalies, as shown in first and second modes, while the third and the fourth mode did not show substantial spatial variability. The dominant temporal variation revealed semi-annual, annual and inter-annual periodicity. Furthermore, for the geostrophic zonal current, spatial pattern in the first to third modes showed high variability around the west coast of Sumatra and south coast of Java, while in the offshore region they showed positive-negative anomalies. In the fourth mode, the spatial pattern showed low variability. The dominant temporal variation revealed annual, semi-annual and inter-annual periodicity. Based on the spatial and temporal variation of the data, the variability in the study area might be associated with the dynamic of coastally trapped Kelvin wave, upwelling and an inter-annual anomaly of IOD and ENSO. It was also noticed that some patterns indicated as dynamic of SJC and SEC signals.Altimeter data, geostrophic zonal component, sea level anomaly, the Eastern Indian Ocean, time-series analysis EOF, variability
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(Downloads: 11)
Abstract (Viewed: 2)Clay soil has always been associated with low shear strength and high compression behavior due to the high content of organic matter. The limited amounts of clay available onsite and acid mine drainage (AMD) problems have necessitated the continuous search for the treatment technology potentials. Mining soils, obtained from Selinsing Gold Mine in Raub, Pahang were evaluated to determine their suitability for use as mining soil and steel slag mixtures as compacted retention pond liners for AMD treatment. The studied samples were subjected to classification, compaction, permeability and strength tests. The results indicated that the index properties of the samples met the minimum requirements for use as liners. The compaction test showed that the maximum dry density (MDD) and optimum moisture content (OMC) decreased and increased, respectively, for all studied samples. At OMC, hydraulic conductivities of the compacted soil-steel slag were in the order of ≤ 10-9 m/s. The results from unconfined compression strength (UCS) tests gave values of 204 kN/m2 and 61° for soil cohesion and soil internal friction angle, respectively. Furthermore, the influence of steel slag treatment on strength properties has generally shown an improvement of up to 15% steel slag which gives the acceptable results of stress-strain in respect of its usability as liner material.Hydraulic conductivity, liner, mining soil, steel slag, strength parameters
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(Downloads: 10)
Abstract (Viewed: 2)The distribution of dissolved iron (dFe) and particulate iron in the estuarine system was studied where in-situ water sampling stations were selected at Bagan Pasir, Perak. The concentration of dFe was 1.17±0.28 mg/L on average at the estuary, while in freshwater samples its concentration was 0.08±0.00 mg/L. This study found that the concentration of particulate Fe in freshwater system was higher than that in the estuary system. The Fe concentration was 0.95±0.03 mg/kg and 0.80±0.18 mg/kg at the freshwater and estuary systems, respectively. We have applied a distribution coefficient (KD) in order to quantify the partitioning of Fe between the particulate (>0.45 µm) and dissolved (<0.45 µm) phases. The KD value of Fe in the freshwater system was much higher compared to that in the estuary, where the KD value was 12.18 in freshwater and 0.48 -1.31 in the estuary. This indicated that Fe in this area has a strong affinity with the particulate phase in a freshwater system and this is probably due to the anthropogenic input. On the other hand, Fe may exist in colloidal or organic ligands which probably originate from surface sediment or a biological process in water columns at the estuarine area.Dissolved iron, estuary, particulate iron, seawater, voltammetry
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(Downloads: 11)
Abstract (Viewed: 2)Determining the response of basin water resources to rainfall and temperature fluctuations is a crucial source of information for basins water resources planning and management. The study used a descriptive, Mann-Kendall trend test (M-K) and Multiple Linear Regression (MLR). The mean, standard deviations and variations were spatially interpolated using the geostatistical technique. The trend results showed an increase in both rainfall and temperature series. However, the only statistically significant trends were in June and September for rainfall series and in February, May, and April for the temperature series. Rainfall exhibited high temporal variability whereas temperature showed high spatial variability. The intra-annual variability was higher than the inter-annual variability, suggesting that the local climate is largely controlled by natural force. The result of the multiple linear regression (R2=0.431), indicates that the hydrology and water resources of the basin are impacted largely by factors not considered in this study such as land use changes, infiltration, and rate of evaporation among others. However, among the factor considered, rainfall (Beta = 0.505; P = 001) has the highest impacts on the river discharge behavior and should be given preference while addressing water resources predicaments in the catchment.Climate variability, geostatistical methods, multiple linear regression, river catchment, semi-arid region
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(Downloads: 11)
Abstract (Viewed: 1)Rough neutrosophic multisets are an improved model of generalization pf neutrosophic multisets represented within the Pawlak’s boundary set of information: lower and upper approximation. The concepts of rough neutrosophic multisets can be easily extended to a relation, mainly since a relation is also a set, i.e. a subset of a Cartesian product. This paper establishes an axiomatic definition of rough neutrosophic multisets relation of Cartesian product over a universal set. Some of the operations and properties of rough neutrosophic multisets, such as max, min, the composition of two rough neutrosophic multisets relation and inverse rough neutrosophic multisets relation, are studied with a proven condition. An algorithm of rough neutrosophic multisets relation is also presented as a step followed to obtain the rough neutrosophic multisets relation. Successful analysis using rough neutrosophic multisets relation theory is represented by the illustrative example of expert opinion about automobile popularity. In conclusion, with a specified condition in uncertainty information, rough neutrosophic multiset relations are generalized in terms of the relation properties of a rough fuzzy relation, rough intuitionistic fuzzy relation, and rough neutrosophic relation over universal. Subsequently, their properties could also be examined.Max, min, neutrosophic multisets, relation, rough neutrosophic multisets, rough set, uncertainty
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Abstract (Viewed: 1)This paper represents the process by which a network is partitioned into smaller network each of which further delegated with a smaller network with a certain degree of autonomy in terms of resource allocation and operation. The term “Autonomy” implies that once the guiding policy is articulated and the resource allocation is decided upon, local management may enjoy some freedom in local, short-term decisions such as dispatching repositioning, budget planning and manning. The implications of zoning prevail over a long period, once a wide network is partitioned into sub network, each sub network will likely be treated as almost an independent network in terms of its “rights” to possess and to operate resources.Autonomy, delegated, network, partition, resources
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Abstract (Viewed: 2)In this paper, we present the absolute stability of the existing 2-point implicit block multistep step methods of step number k = 3 and k = 5 and solving special second order ordinary differential equations (ODEs). The methods are then trigonometrically fitted so that they are suitable for solving highly oscillatory problems arising from the special second order ODEs. Their explicit counterparts are also trigonometrically fitted so that in the implementation the methods can act as a predictor-corrector pairs. The numerical results based on the integration over a large interval are given to show the performance of the proposed methods. From the numerical results we can conclude that the new trigonometrically-fitted methods are superior in terms of accuracy and execution time, compared to the existing methods in the scientific literature when used for solving problems which are oscillatory in nature.Block method, multistep method, oscillatory problems, special second order ODEs, trigonometrically fitted
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Abstract (Viewed: 2)Parboiling process has been widely implemented in brown rice processing, but its effect on in vitro physiological antioxidant capacity of brown rice was not known. In this study, an in vitro method simulating the human physiological conditions was used to investigate the effect of parboiling on antioxidant capacity of brown rice in three Bario rice varieties. In this method, bacterial inocula were prepared from rat cecal contents. Results showed that parboiling process gave significant impacts on in vitro physiological antioxidant capacity of brown rice. The process improved total phenolic content at small intestine (Adan Halus), DPPH scavenging activity at both small and large intestines (Adan Halus and Bario Merah) and ferrous ion-chelating activity at large intestine (Bario Hitam). However, changes in antioxidant capacity were variety dependent, possibly due to different bran pigmentation. These suggested that parboiling process could improve physiological antioxidant capacity with in vitro simulation at small and large intestines by selecting a suitable rice variety and parboiled brown rice could offer good antioxidant properties to maintain physiological health.Bario rice, brown rice, DPPH scavenging activity, ferrous chelating activity, in vitro physiological antioxidant capacity, parboiled rice, total phenolic content
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Abstract (Viewed: 1)Sea cucumber has a thick layer of skin consisting of lime components. In fact, the components contain chitin and chitosan, which have been recognized as potential sources materials for dietary supplement. This study aimed at evaluating the physical and chemical characteristics of chitosan nanoparticles extracted from sea cucumber Holothuria scabra when used as source materials for glucosamine. Chitin were extracted from dried samples, chitosan from chitin, while chitosan nanoparticles were obtained from chitosan with different concentrations (C1 = 0.1%; C2 = 0.2%; C3 = 0.3%) of added sodium tripolyphosphate (NaTPP). Production process in this study resulted in 59.82% of chitosan extracted from chitin. Besides, the amount of chitosan nanoparticles obtained at 0.1%, 0.2%, and 0.3% additions of NaTPP were 90.6%, 92.8%, and 96.4%, respectively. These results were characterized in terms of whiteness degree (85.82%, 87.29%, 88.34%, respectively), deacetylation degree (90.6%, 95.8%, 96.2%), moisture (5.73%, 5.26%, 4.82%), and ash (1.29%, 1.07%, 0.98%). Looking at SEM and PSA tests, chitosan was morphologically found to be heterogeneously distributed with averaged 177-micron particle sizes. They also had larger particle chunks and solid as well as intact forms. Meanwhile, chitosan nanoparticles had smaller and smoother chunks, while they were produced in solid and intact forms. Besides, they were homogeneously distributed with sizes ranging between 134 − 206 nm (C1), 114-128 nm (C2), and 97-108 nm (C3). Then, increments in NaTPP concentrations were discovered to contribute to the reduction of H. scabra-sourced chitosan nanoparticles size.Chitosan, Holothuria scabra, nanoparticles, sodium tripolyphosphate
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Abstract (Viewed: 1)This work investigates the hydrothermal synthesis and characterization of zeolite-4A from kaolin found in Ajebo, Nigeria calcined at 700 and 900°C respectively. The synthesized zeolite-4A was further characterised using X-ray Fluorescence (XRF), Fourier Transform Infrared spectrometer (FTIR), Scanning Electron Microscopy (SEM), X-Ray diffraction (XRD), Brunauer-Emmet-Teller (BET) surface area analysis as well as Differential Thermal Analysis/Thermo-gravimetric (TG). Water adsorption capacity tests were also carried out on the synthesized zeolite-4A. The results from the XRF measurements indicated that the amount of Al2O3 and SiO2 in the studied kaolin was similar to the standard kaolin composition making it a perfect candidate for zeolite-4A synthesis. FTIR showed the characteristic zeolite peaks while XRD confirmed the crystalline nature of the synthesized zeolite-4A. TG studies showed that the zeolite-4A samples were stable up to temperatures of 700°C. This stability as well as the surface area and pore size of 7 Ä makes it potentially suitable for use in water treatment applications. The SEM showed cubic crystals which were typical of the morphology of zeolite-4A with water adsorption capacity of approximately 29%. These results indicate that zeolite- 4A can be synthesized from kaolin found in Ajebo as an inexpensive alternative to traditionally sourced materials and also is suitable for use as adsorption agent.Adsorption agent, Ajebo kaolin, hydrothermal, metakaolin, zeolite-4A
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Abstract (Viewed: 2)This study aims to characterise the scattered dose distribution from a ceiling-mounted X-ray unit in a multi-bay resuscitation room. The finding of this study is essential for optimisation and safety of staff and patients. Simulation of phantom imaging was carried out using MCNP5 code. The calculated data were initially compared against the measurements carried out using a survey meter. Three measurement positions, denoted by T2, T3, and T4 were considered for the dose calculation. The data suggested that T2 received the highest scattered dose. This value (maximum value of less than 6 µGy) is lower than the annual dose limit for the public and radiation workers as well as natural background radiation dose. Meanwhile, T3 consistently received a higher scattered dose (maximum difference of 25.62%) than T4. The angles of the X-ray tube resulted in scattered doses less than 6 µGy for both 90° and 100° scattering angles. In conclusion, the scattered dose for a single exposure imaging inside the room is safe. Yet, consideration of the placement of a portable lead shielding between X-ray tube and treatment couch is strongly recommended. This is due to a high number of imaging procedures commonly performed daily in a busy hospital. Hence, the cumulative dose to the paramedic staff and patients may exceed the safe level.MCNP5, scattered dose, x-ray room

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