310 research outputs found

    Feature selection for malicious android applications using Symmetrical Uncert Attribute Eval method

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    The fast growth of tablets, smartphones has led to increase the usage of mobile applications. The Android apps have more popularity, however, the applications downloaded from third-party markets could be malware that may threaten the users' privacy. Several works used techniques to detect normal apps from malicious apps based on mining requested permissions. However, there are some set of permissions that can occur in benign and malignant applications. Redundant features could reduce the detection rate and increase the false positive rate. In this paper, we have proposed feature selection methods to identify clean and malicious applications based on selecting a set combination of permission patterns using different classification algorithms such as sequential minimal optimization (SMO), decision Tree (J48) and Naive Bayes. The experimental results show that sequential minimal optimization (SMO) combining with SymmetricalUncertAttributeEval method achieved the highest accuracy rate of 0.88, with lowest false positive rate of 0.085 and highest precision of 0.910. And the findings prove that feature selection methods enhanced the result of classification

    Circular Microstrip Patch Antenna for UHF RFID Reader

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    This paper presents an analysis of Circular shape patch antenna for Ultra High-Frequency Identification (UHF) Radio Frequency Identification (RFID) Reader Applications. The fabricated antenna has lightweight, simple structure, low profile and easy for fabrication due to the used of FR-4 materials with loss tangent 0.019, the dielectric constant of 4.7 and thickness of 1.6 mm. It can be operated for UHF RFID system in Malaysia with the frequency assigned from 919 MHz to 923 MHz. The antenna simulation was analysed by using CST Studio Suite 2016. From the results, the antenna has the reflection coefficient (S11) less than -10dB together with the bandwidth of 90 MHz. Other results of antenna parameter such as voltage standing wave ratio (VSWR), circular polarized radiation pattern, return loss and gain were also discussed. The complete size of the proposed antenna is 120 mm x 120 mm x 1.6 mm. Thus, it is suitable for RFID portable reader applications

    Finger vein biometric identification using discretization method

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    Over the past years, finger vein identification has gaining increasing attention in biometrics. It has many advantages as compared to other biometrics such as living-body identification, difficult to counterfeit because it resides underneath the finger skin and noninvasiveness. Finger vein feature extraction plays an important role in finger vein identification. The performance of finger vein identification is highly depending on the meaningful extracted features from feature extraction process. However, most of the works focus on how to extract the individual features and not presenting the individual characteristic of finger vein patterns with systematic representation. This paper proposed an improved scheme of finger vein feature extraction method by adopting discretization method. The extracted features will be represented systematically way in order to make classification task easier and increase the identification accuracy rate. The experimental result shows that the accuracy rate of identification of the proposed framework using Discretization is above 98.0%

    Effect of wall resistance on the total thermal resistance of a stacked microchannel heat sink

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    This paper reports on the different modeling approach of the total thermal resistance in a microchannel heat sink (MCHS); with wall resistance and the frequently used fin model, in comparison with experimental results. For a single stack MCHS, the wall model caused more than 10% difference but it can be extended to a stacked MCHS while the fin model could not, due to the adiabatic top condition. The wall resistance model is idealized, assuming a 100% efficient convective heat transfer while in the fin model 70% was the maximum. Meanwhile, stacking showed that at a constant flow rate, the thermal resistance could be reduced by 3% for a double stack, while increasing beyond that will decrease the thermal performance of the MCHS. The study showed the limits of models used and possible stacking of a MCHS for improved heat removal capability

    Optimization of cerbera manghas biodiesel production using artificial neural networks integrated with ant colony optimization

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    © 2019 by the authors. Optimizing the process parameters of biodiesel production is the key to maximizing biodiesel yields. In this study, artificial neural network models integrated with ant colony optimization were developed to optimize the parameters of the two-step Cerbera manghas biodiesel production process: (1) esterification and (2) transesterification. The parameters of esterification and transesterification processes were optimized to minimize the acid value and maximize the C. manghas biodiesel yield, respectively. There was excellent agreement between the average experimental values and those predicted by the artificial neural network models, indicating their reliability. These models will be useful to predict the optimum process parameters, reducing the trial and error of conventional experimentation. The kinetic study was conducted to understand the mechanism of the transesterification process and, lastly, the model could measure the physicochemical properties of the C. manghas biodiesel

    Kebolehupayaan sistem penuaian hujan sebagai bekalan air alternatif di Malaysia: Suatu penelitian awal

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    Sistem Penuaian Air Hujan dianggap sebagai Kaedah Pengurusan Terbaik atau "Best Management Practice (BMP)" yang diamalkan di Malaysia. Sistem ini bukan sahaja bertujuan untuk melambatkan aliran air larian permukaan malahan ianya juga dijadikan sebagai sumber bekalan air alternatif yang percuma dan selamat digunakan. Terdapat juga pandangan yang mengatakan sistem tersebut tidak viable dan praktikal memandangkan kos binaan dan penyelenggaraan yang terpaksa ditanggung oleh pengguna sistem berkenaan. Bagaimanapun, terdapat beberapa kajian di dalam dan diluar negara menunjukkan faktor ‘return on capital’ atau ROC bagi sistem ini hanyalah di dalam tempoh masa yang pendek, iaitu antara dua hingga tiga tahun. Artikel ini cuba meneliti tapak pelaksanaan sistem berkenaan di kampus Universiti Kebangsaan Malaysia sebagai makmal ujikaji khusus. Hasil pengoperasian sistem analisis TANGKINAHRIM (2010), telah mendapati taburan hujan yang konsisten sepanjang tahun, di samping keluasan tapak tadahan air yang besar dan mencukupi untuk kegunaan operasi pejabat di Fakulti Sains Sosial dan Kemanusiaan. Kebolehpercayaan terhadap sistem berkenaan adalah tinggi iaitu 89.3% dan didapati saiz tangki yang optimum adalah di sekitar 60 hingga 65 meter padu air yang mampu diisi. Anggaran saiz berkenaan adalah didapati bersesuaian dengan saiz tadahan, jumlah populasi (pengguna) dan juga perletakan lokasi yang strateg

    DNA adducts in human urinary bladder and other tissues.

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    Tobacco smoking is associated with an increased risk of cancer in a number of organs, including bladder and lung. Tobacco smoke contains at least 50 known chemical carcinogens that exert their biological effects through their covalent binding to cellular DNA. Examining human DNA for the presence of altered nucleotides is a means of monitoring exposure to genotoxic chemicals. DNA isolated from 73 human bladder biopsies has been analyzed by 32P-postlabeling for the presence of aromatic/hydrophobic adducts. Butanol extraction of DNA digests resulted in up to a 3-fold greater recovery of adducts than nuclease P1 digestion. Among 16 nonsmokers, adduct levels were in the range 3.2-20.8/10(8) nucleotides (mean 9.7). Eight ex-smokers had values in the range 2.6-12.3 (mean 7.1). Thirteen smokers had adduct levels between 1.3 and 26.7 adducts/10(8) nucleotides (mean 9.5, not different from nonsmokers). Six cigar smokers had higher levels of adducts (mean 12.1, range 7.3-15.0), but pipe smokers did not (five samples, mean 8.6, range 2.9-12.7). A further 8 samples from nonsmokers and 17 from smokers were examined in more detail. Although most of the DNA binding appears not to be smoking related, the levels of one adduct were found to be on average 2-fold higher in smokers (p < 0.005, one-tailed t test). Studies on tissues of the respiratory tract demonstrate a correlation between DNA adduct levels and exposure to tobacco smoke. Evidence to date on the influence of smoking on adducts in peripheral blood cells is equivocal; some studies demonstrate a significant effect, whereas others do not.(ABSTRACT TRUNCATED AT 250 WORDS

    Nanofluid-cooled microchannel heat sink with carbon nanotube

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    Concerns over the exponential increase in the heat produced per unit area in electronic chips have driven advanced research into the nanofluid capability as a coolant. Generally reported for its improved thermal conductivity in particular at higher concentrations, different types of surfactant normally added used to stabilize the nanofluid have reported different thermal resistance to heat flow. This paper reports an analysis of the thermal performance of a nanofuid-cooled microchannel heat sink (MCHS) with 0.1% volume fraction of CNT nanofluid utilizing two different surfactants; Lignin (N2) and sodium polycarboxylate (N3) as stabilizers. Multi-objective particle swarm optimization (MOPSO) algorithm was utilized to simultaneously minimize the thermal resistance and pumping power by optimizing the design parameters; the wall width and channel aspect ratios. Optimization outcomes showed that the thermal resistance of CNT nanofluids is lower than water by 1% at 20°C. Nanofluid with N3 has a significantly higher pressure drop than water, up to 47%. CNT nanofluid with N3 performed poorly due to the high viscosity which consequently results both in higher thermal resistance and pressure drop. Since a surfactant alters the properties of nanofluid, it could improve or deteriorate the performance of a MCHS overall and must not be taken lightly as a MCHS is expected to operate for a long time

    Case-control investigation on the risk factors of melioidosis in small ruminant farms in Peninsular Malaysia

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    Aims: Epidemiology of melioidosis is poorly understood because its occurrence is influenced by complex interaction of environmental, climatic, physicochemical and host factors. We investigated the potential risk factors for the exposure to Burkholderia pseudomallei in small ruminants' farms in Peninsular Malaysia. Methods and results: Melioidosis-positive (n = 33) and negative (n = 27) farms were selected and visited for interviews and environmental samples collection. The characteristics and putative disease risk factors were compared between the case and the control farms using Chi-square test and logistic regression analysis. The multivariable logistic regression analysis showed that the odds of melioidosis were significantly higher in farms that had bush clearing around farms (odds ratio (OR) = 6.61, 95% confidence interval (CI) = 1.12-38.84, P = 0.037), in farms with B. pseudomallei present in the soil (OR = 6.23, 95% CI = 1.03-37.68, P = 0.046), in farms that have other animal species present (OR = 7.96, 95% CI = 1.14-55.99, P = 0.037) and in farms that had flooding or waterlogging conditions (OR = 11.95, 95% CI = 1.39-102.6, P = 0.024) when compared to the odds of the disease in farms that did not have the above conditions. The odds of the disease in farms that treated their soils with lime were significantly lower (OR = 0.028, 95% CI = 0.003-0.29, P = 0.003) compared to the odds in those that did not. Conclusions: The risk factors for the exposure to B. pseudomallei highlighted above may have contributed to the occurrence of melioidosis in animals in the study farms. Significance and impact of the study: Information from the study may be helpful in planning control measures against melioidosis and have improved understanding of the epidemiology of the disease in livestock farms
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