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Subspace Clustering in High-Dimensional Data Streams:A Systematic Literature Review

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Computers, Materials & Continua 2023年第5期75卷 4649-4668页

作者： Nur laila Ab Ghani Izzatdin abdul Aziz Said Jadid abdulKadir Department of Computer and Information Sciences Universiti Teknologi PETRONASSeri Iskandar32610PerakMalaysia Centre for Research in Data Science(CeRDAS) Universiti Teknologi PETRONASSeri Iskandar32610PerakMalaysia

Clustering high dimensional data is challenging as data dimensionality increases the distance between data points,resulting in sparse regions that degrade clustering *** clustering is a common approach for processing high-dimensional data by finding relevant features for each cluster in the data *** clustering methods extend traditional clustering to account for the constraints imposed by data *** streams are not only high-dimensional,but also unbounded and *** necessitates the development of subspace clustering algorithms that can handle high dimensionality and adapt to the unique characteristics of data *** many articles have contributed to the literature review on data stream clustering,there is currently no specific review on subspace clustering algorithms in high-dimensional data ***,this article aims to systematically review the existing literature on subspace clustering of data streams in high-dimensional streaming *** review follows a systematic methodological approach and includes 18 articles for the final *** analysis focused on two research questions related to the general clustering process and dealing with the unbounded and evolving characteristics of data *** main findings relate to six elements:clustering process,cluster search,subspace search,synopsis structure,cluster maintenance,and evaluation *** algorithms use a two-phase clustering approach consisting of an initialization stage,a refinement stage,a cluster maintenance stage,and a final clustering *** density-based top-down subspace clustering approach is more widely used than the others because it is able to distinguish true clusters and outliers using projected *** algorithms implicitly adapt to the evolving nature of the data stream by using a time fading function that is sensitive to *** work can focus on the clustering framework,parameter optimiza

关键词： Clustering subspace clustering projected clustering data stream stream clustering high dimensionality evolving data stream concept drift

Anthropogenic disturbance of aquatic biodiversity and water quality of an urban river in Penang, Malaysia

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Water Science and Engineering 2023年第3期16卷 234-242页

作者： Nur Azalina Suzianti Feisal Noor Haziqah Kamaludin Muhammad Firdaus abdullah Sani dayang Khairulnisa Awang Ahmad Mohd Azwan Ahmad Nur Faiza abdul Razak Tengku Nilam Baizura Tengku Ibrahim Department of Environmental Health Faculty of Health SciencesMAHSA UniversityBandar Saujana Putra42610 JenjaromMalaysia Center of Environmental Health&Safety Faculty of Health SciencesUniversiti Teknologi MARA42300 Puncak AlamMalaysia NaturePRO Services Port Dickson71000 Negeri SembilanMalaysia Department of Environmental Health Faculty of Health SciencesUniversiti Teknologi MARACawangan Pulau PinangKampus Bertam13200 Pulau PinangMalaysia

Malaysia's rapid economic and demographic development have placed negative pressure on its water supplies and the quality of the Juru River, which is close to the nation's capital and its major source of water. Healthy aquatic ecosystems are supported by physicochemical properties and biological diversity. This study evaluated the anthropogenic impacts on aquatic biodiversity, especially plankton, fish, and macrobenthos, as well as the water quality of the Juru River in the Penang area. Aquatic biodiversity and river water parameters were collected from ten sampling stations along the Juru River. Seven variables were used to assess the physicochemical environment: pH, temperature, total suspended solids (TSS), salinity, dissolved oxygen (DO), biochemical oxygen demand (BOD), and chemical oxygen demand. At each sampling station, the total number of plankton, fish, and macrobenthic taxa were counted and analyzed. The relationships between the physicochemical parameters and aquatic biodiversity were investigated with biotypological analysis, principal component analysis, hierarchical cluster analysis, and linear regression analysis. These analyses showed that the richness and diversity indices were generally influenced by salinity, temperature, TSS, BOD, and pH. The data obtained in this study supported the bioindicator concept. The findings, as they related to scientifically informed conservation, could serve as a model for Juru River management, as well as for river management throughout Malaysia and other tropical Asian countries.

关键词： Anthropogenic disturbance Aquatic biodiversity River water quality Urban river Hierarchical cluster analysis

Phytoconstituent Screening and Antibacterial Activity of the Leaf Extracts from Canarium odontophyllumMiq.

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American Journal of Plant Sciences 2014年第19期5卷 2878-2888页

作者： dayang Fredalina Basri Nur Hafidzah Mohd Nor School of Diagnostic & Applied Health Sciences Faculty of Health Sciences Universiti Kebangsaan Malaysia Jalan Raja Muda Abdul Aziz 50300 Kuala Lumpur Malaysia

Canarium odontophyllum is one of the underutilized fruits among the local community in Sarawak, Malaysia. The leaf extracts from C. odontophyllum (6.25 mg/ml to 50 mg/m) were screened against two Gram-positive bacteria (Staphylococcus aureus and Bacillus cereus) and two Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa). Extraction of the C. odontophyllum leaves using methanol produced the highest yield (5.46%) followed by water (4.0%) and acetone (2.83%) whereas hexane extracted the lowest yield (0.98%). Out of the four bacterial species tested, only S. aureus was found to be susceptible towards the C. odontophyllum leaves extract. Screening result using agar well diffusion method showed that the antimicrobial activity of the acetone and methanol extracts from C. odontophyllum leaves was concentration-dependent towards the growth inhibition of S. aureus. The MIC values for both MeOH and acetone extracts were 0.391 mg/ml. The MBC value of MeOH extract was twice its MIC value whereas the MBC and MIC values of acetone extract against S. aureus were the same. Phytochemical analysis showed that acetone, MeOH and water extracts contain flavonoid, tannin, terpenoid and phenol. These findings conclude that the leaves of C. odontophyllum may contain therapeutically-useful compounds against S. aureus, which are mostly concentrated in the acetone extract. As such, C. odontophyllum have the potential to be developed as an alternative treatment against Staphylococcus aureus-associated skin and soft tissue infections.

关键词： Leaves Canarium odontophyllum Flavonoid Saponin Antibacterial Agar Well Diffusion Staphyloccocus aureus MIC MBC

Numerical Investigation of the Plasma Formation in Distilled Water by Nd-YAG Laser Pulses of Different Duration

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Journal of Modern Physics 2012年第10期3卷 1683-1691页

作者： laila H. Gaabour Yosr Ezz El Din Gamal G. Abdellatif Department of Physics Girl’s Faculty of Science King Abdul-Aziz University Jeddah KSA Physics Department Faculty of Science Cairo University Giza Egypt

Water breakdown studies by Nd-YAG laser pulses of duration 100 fs, 30 ps and 6 ns at wavelength 1064 nm are pre- formed to investigate the physical mechanisms which couple the laser energy into the medium. Calculations are carried out applying a modified kinetic model of water breakdown previously developed by Kennedy (1995) to investigate the correlation between threshold intensity of breakdown and laser pulse length. The modifications considered the introduction of diffusion and recombination loss processes which might take place under the experimental conditions applied in these calculations. The validity of the model is tested by comparing the calculated threshold intensities and the experimentally measured ones where good agreement is shown. The study of the time evolution of the electron density clarifies the correlation between the pulse length and dominant ionization mechanism. The analysis of the spatial distribution of the electron density along the radial and axial distances of the focal spot showed that the size of the formed plasma increases with the increase of the pulse length. On the other hand, studies of self-focusing effect illustrated that under the investigated experimental conditions the effect of this process has an effective contribution only at laser pulses of the order of femtosecond scale when the laser beam is focused by a lens of a focal length ≥8.0 cm. This result in turns assures that using femtosecond pulses in ophthalmic microsurgery could be a safe tool from the retinal damage.

关键词： Laser Induced Breakdown Water Breakdown Electron Density Self Focusing Modeling of Plasma Formation Laser Medicine

Analysis of Two-Dimensional Gel Electrophoresis Map of Methicillin-Resistant Staphylococcus aureusTreated with Acetone Extract from Canarium odontophyllumMiq. Leaves

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American Journal of Plant Sciences 2021年第1期12卷 37-52页

作者： Nur Amira Mohd Shamsuddin dayang Fredalina Basri Noraziah M. Zin Ahmad Raha Raus Nur Faizah Abu Bakar Centre for Diagnostic Therapeutic & Investigative Studies (CODTIS) Faculty of Health Sciences Universiti Kebangsaan Malaysia Jalan Raja Muda Abdul Aziz Kuala Lumpur Malaysia Department of Biotechnology Engineering Faculty of Engineering International Islamic University Malaysia Kuala Lumpur Malaysia

Methicillin-resistant Staphylococcus aureus (MRSA) infection is a global health concern that has caused severe health threats over the past decade. Leaves extract of C. odontophyllum has been proven previously as an anti MRSA agent. Proteomics provide a technique that used to analyze the differential of protein expression profile between untreated and treated MRSA with subinhibitory concentrations of acetone extract from C. odontophyllum leaves. This study aims to determine the optimum parameter for analysis of protein expression profile using two-dimension gels electrophoresis (2-DE) for MRSA protein after treatment with acetone extract from C. odontophyllum leaves. Comparison of the Protein Expression Profile (PEP) between the untreated and treated MRSA was analyzed using PDQuest software. The optimum condition for MRSA protein treated with acetone extract from C. odontophyllum leaves to produce the best resolution with greater spot distribution was as follows: 100 μg volume of MRSA protein that loaded after passive rehydration then was run until reaching 25 kVrhs during IEF using 17 cm IPG strip wit

关键词： Canarium odontophyllum MRSA 2-DE IEF SDS-PAGE Protein Expression Profile

Energy Levels, Oscillator Strengths, and Transition Probabilities of Ni XIX and Cu XX

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Optics and Photonics Journal 2014年第3期4卷 54-89页

作者： Wessameldin S. Abdelaziz M. Atta Khedr Mai E. Ahmed laila Gaabour Tharwat El-Shirbini Environmental Affairs Agency Cairo Egypt Laboratory of Lasers and New Materials Cairo University Giza Egypt National Institute of Laser Enhanced Sciences Cairo University Giza Egypt Physics Department Faculty of science King Abdul Aziz University Jeddah Saudi Arabia

Energy levels, oscillator strengths, and transition probabilities, for the 1s2 2s2 2p6, 2p53l (l = 0, 1, 2), 2p54l (l = 0, 1, 2, 3) states in Ni XIX and Cu XX are calculated using COWAN code. The Correlation and relativistic effects are considered. The calculations are compared with other results in the literature. A good agreement is found. We also report on some unpublished energy values.

关键词： Energy Levels Oscillator Strengths Transition Probabilities