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Applied Mathematics and Mechanics(English Edition) 2012年第2期33卷 195-210页

作者： M.Q.al-ODAT a.al-GHAMDI Mechanical Engineering Department Faculty of EngineeringUmm Al-Qura UniversityMakkahKingdom of Saudi Arabia Mechanical Engineering Department Al-Huson University CollegeAl-Balqa Applied UniversityIrbidJordan

The Dufour and Soret effects on the unsteady twodimensional magnetonyaro dynamics （MHD） doublediffusive free convective flow of an electrically conducting fluid past a vertical plate embedded in a nonDarcy porous medium are investigated numeri cally. The governing nonlinear dimensionless equations are solved by an implicit finite difference scheme of the CrankNicolson type with a tridiagonal matrix manipulation. The effects of various parameters entering into the problem on the unsteady dimension less velocity, temperature, and concentration profiles are studied in detail. Furthermore, the time variation of the skin friction coefficient, the Nusselt number, and the Sherwood number is presented and a.alyzed. The results show that the unsteady velocity, tem perature, and concentration profiles are substantially influenced by the Dufour and Soret effects. When the Dufour number increases or the Soret number decreases, both the skin friction and the Sherwood number decrease, while the Nusselt number increases. It is found that, when the magnetic parameter increases, the velocity and the temperature decrease in the boundary layer.

关键词： double-diffusive free convection non-Darcy model magnetohydrodynamic(MHD) porous medium Dufour effect Soret effect numerical solution

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Machine Learning Empowered Electricity Consumption Prediction

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Computers, Materials & Continua 2022年第7期72卷 1427-1444页

作者： Maissa a.al Metrik Dhiaa A.Musleh Department of Computer Science College of Computer Science and Information TechnologyImam Abdulrahman Bin Faisal UniversityDammam31441Saudi Arabia

Electricity,being the most efficient secondary energy,contributes for a larger proportion of overall energy *** to a lack of storage for energy resources,over supply will result in energy dissipation and substantial investment *** electricity consumption prediction is vital because it allows for the preparation of potential power generation systems to satisfy the growing demands for electrical energy as well as:smart distributed grids,assessing the degree of socioeconomic growth,distributed system design,tariff plans,demand-side management,power generation planning,and providing electricity supply stability by balancing the amount of electricity produced and *** paper proposes amedium-termprediction model that can predict electricity consumption for a given location in Saudi ***,this study implemented a standalone ArtificialNeuralNetwork(ANN)model and bagging ensemble for predicting total monthly electricity consumption in 18 locations across Saudi *** dataset used in this research is gathered exclusively from the Saudi Electric *** pre-processing phase included normalizing the data using min-max method and mapping the cyclical attribute to its sine and cosine *** number of neurons and learning rate of the standalone model were optimized using hyperparameter ***,the standalone model was tested against the bagging ensemble using the optimized *** bagging ensemble with an optimized ANN as the chosen classifier outperformed the standalone ANN *** results for the proposed model produced 0.9116 Correlation Coefficient(CC),0.2836 Mean Absolute Percentage Error(MAPE),0.4578,Root Mean Squared Percentage Error(RMSPE),0.0298 MAE,and 0.069 Root Mean Squared Error(RMSE),respectively.

关键词： Electricity consumption prediction artificial neural network machine learning

Molecular phylogeny of Solms-laubachia(Brassicaceae) s.l.,based on multiple nuclear and plastid DNA sequences,and its biogeographic implications

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Journal of Systematics and Evolution 2009年第5期47卷 402-415页

作者： David A.BAUM Ihsan a.al-SHEHBAZ Richard REE Department of Botany University of Wisconsin Missouri Botanical Garden PO Box 299St LouisMO 63166-0299USA 3. Department of BotanyThe Field Museum1400 S.Lake Shore DriveChicagoIL 60605USA

The Hengduan Mountains region of south-west China is a noted biodiversity hotspot,but the geographic origins and historical assembly of its rich endemic flora,including the sky-island species of Solms-laubachia Muschl.(Brassicaceae),have been little *** molecular studies on the phylogeny of Solms-laubachia showed it to be paraphyletic,leading to considerable expansion not only of its taxonomic limits,but also its geographic range,with the inclusion of taxa from outside the Hengduan ***,these studies provided little resolution of interspecific relationships,preventing inferences about historical biogeography within the *** the present study,new sequence data from two nuclear genes(LEAFY and G3pdh) and two chloroplast intergenic spacers(petN-psbM and psbM-trnD) were combined with existing markers to increase phylogenetic *** villosum(Maxim.) al-Shehbaz was found to be nested within Solms-laubachia *** general,phylogenetic relationships appear to be a good predictor of geography,with the Hengduan Mountain endemics embedded in a paraphyletic grade of species from the western Himalayas and central Asia,but they also imply morphological *** was detected between the nuclear and chloroplast gene trees,perhaps resulting from incomplete lineage sorting of ancestral *** crown age of Solms-laubachia *** estimated to be approximately 1.42-3.68 mya,using Bayesian relaxed molecular clock *** biogeographic a.alysis using a parametric dispersal-extinction-cladogenesis model inferred central Asia and the western Himalayas as most probable ancestral range of Solms-laubachia s.l.,and estimated higher rates of eastward expansion than westward during the diversification of descendant *** summary,our results suggest that Solms-laubachia *** during the Pliocene in central Asia,and subsequently migrated eastward into the Hengduan Mountains,colonizing sky-island,alpine scr

关键词： biogeography Brassicaceae Hengduan Mountains phylogeny Solms-laubachia s.l.

Effects of Rate and Source Organo-Mineral Material on Forage Yield and Nutritive Value of Barley-Pea Mixed under Arid Conditions

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Phyton-International Journal of Experimental Botany 2022年第7期91卷 1483-1493页

作者： Walid Soufan Nasser a.al-Suhaibani Plant Production Department College of Food and Agriculture SciencesKing Saud UniversityRiyadh11451Saudi Arabia

Cereal-legume intercropping plays a vital role in the subsistence food production system that prevails in the arid *** not only provides profitable crop productivity for agricultural communities but also plays an important role in improving soil ***,the present research was conducted to assess the effect of the organic and mineral fertilizers on the forage yield and nutritional value in barley-pea intercropping *** results revealed that the quality of forage grass is significantly influenced by both organic and inorganic ***,organic fertilizer application has significantly influenced the dry matter(DM),crude ash(CA),crude protein(CP),neutral detergent fiber(NDF),and acid detergent fiber(ADF).Among the treatments,organic fertilizer added at rate of 35 m^(−3) ha^(−1) produced the maximum fresh and dry matter in barley and *** addition,the same level of organic fertilizer also improved silage composition by significantly increasing the protein and fiber content and showed highest the *** on overall results,it is concluded that organic fertilizer treatment(35 m^(−3) ha^(−1))has the potential as an effective strategy to improve the productivity and nutritional quality of the barley-pea intercropping system in arid *** results revealed that organic fertilizer can be utilized in sustainable agricultural as a source of nutrients for numerous various crops under arid conditions.

关键词： Organic fertilizer barley pea yield quality hay silage

Stereoselective interactions of chiral dipeptides on amylose based chiral stationary phases

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Science China Chemistry 2015年第3期58卷 519-525页

作者： Imran ali Ashanul Haque Zeid a.al-Othman Abdulrahman al-Warthan Leonid Asnin Department of Chemistry Jamia Millia Islamia Central University Department of Chemistry College of Science King Saud University Perm National Research Polytechnic University

Dipeptides are stereo-specifically involved in several biological functions that are challenging to separate enantiomerically. Elution order of enantiomers is an important issue in chiral chromatography. Amylose tris-(3,5-dimethylphenylcarbamate) chiral stationary phase(CSP) is the best and most-widely-used CSP in chiral separations, but experimental data of enantiomeric separation of dipeptides on this CSP is lacking. Simulation studies were conducted to determine the order of elution and the chiral recognition mechanism of didpetides on this CSP. Results indicated that the docking energy of SR-enantiomers were higher than SS-antipodes. The range of docking energies for SR-enantiomers was -7.44 to -5.92 kcal/mol with CSP, but -7.15 to -5.87 kcal/mol for SS-stereoisomers. Therefore it is predicted that SS-enantiomer will elute first, followed by SR-antipode. Furthermore, hydrogen bondings, van der Waal's interactions and electrostatic interactions were observed among SR- and SSenantiomers and chiral grooves of CSP. The number of hydrogen bonds was one in each enantiomer binding except S-ala-R-Tyr, which contained two hydrogen bonds. No hydrogen bond was found in S-ala-R-Trp, S-Leu-S-Trp, and S-Leu-S-Tyr dipeptides bindings. The chiral recognition mechanisms dictate different strengths of stereoselective bindings of the enantiomers on CSP.

关键词： dipeptide enantiomers amylose tris-(3 5-dimethylphenylcarbamate) chiral recognition mechanism elution order Auto Dock 4.2.

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Educational Videos Subtitles’Summarization Using Latent Dirichlet allocation and Length Enhancement

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Computers, Materials & Continua 2022年第3期70卷 6205-6221页

作者： Sarah S.alrumiah a.al a.al-Shargabi Department of Information Technology College of ComputerQassim UniversityBuraydah51452Saudi Arabia

Nowadays,people use online resources such as educational videos and ***,such videos and courses are mostly long and thus,summarizing them will be *** video contents(visual,audio,and subtitles)could be a.alyzed to generate textual summaries,i.e.,***’subtitles contain significant ***,summarizing subtitles is effective to concentrate on the necessary *** of the existing studies used Term Frequency-Inverse Document Frequency(TF-IDF)and Latent Semantic a.alysis(LSA)models to create lectures’*** study takes another approach and applies LatentDirichlet allocation(LDA),which proved its effectiveness in document ***,the proposed LDA summarization model follows three *** first phase aims to prepare the subtitle file for modelling by performing some preprocessing steps,such as removing stop *** the second phase,the LDA model is trained on subtitles to generate the keywords list used to extract important *** in the third phase,a summary is generated based on the keywords *** generated summaries by LDA were lengthy;thus,a length enhancement method has been *** the evaluation,the authors developed manual summaries of the existing“EDUVSUM”educational videos *** authors compared the generated summaries with the manual-generated outlines using two methods,(i)Recall-Oriented Understudy for Gisting Evaluation(ROUGE)and(ii)human *** performance of LDA-based generated summaries outperforms the summaries generated by TF-IDF and *** reducing the summaries’length,the proposed length enhancement method did improve the summaries’precision *** domains,such as news videos,can apply the proposed method for video summarization.

关键词： Subtitle summarization educational videos topic modelling LDA extractive summarization

Evolutionary Multi-objective Portfolio Optimization in Practical Context

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International Journal of Automation and computing 2008年第1期5卷 67-80页

作者： S.C.Chiam a.al Mamum Department of Electrical and Computer Engineering National University of Singapore4 Engineering Drive 3Singapore 117576Singapore

This paper addresses evolutionary multi-objective portfolio optimization in the practical context by incorporating realistic constraints into the problem model and preference criterion into the optimization search process. The former is essential to enhance the realism of the classical mean-variance model proposed by Harry Markowitz, since portfolio managers often face a number of realistic constraints arising from business and industry regulations, while the latter reflects the fact that portfolio managers are ultimately interested in specific regions or points along the efficient frontier during the actual execution of their investment orders. For the former, this paper proposes an order-based representation that can be easily extended to handle various realistic constraints like floor and ceiling constraints and cardinality constraint. An experimental study, based on benchmark problems obtained from the OR-library, demonstrates its capability to attain a better approximation of the efficient frontier in terms of proximity and diversity with respect to other conventional representations. The experimental results also illustrated its viability and practicality in handling the various realistic constraints. A simple strategy to incorporate preferences into the multi-objective optimization process is highlighted and the experimental study demonstrates its capability in driving the evolutionary search towards specific regions of the efficient frontier.

关键词： Evolutionary computation multi-objective optimization portfolio optimization preference-based multi-objective optimization constraint handling

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Network Quality Assessment in Heterogeneous Wireless Settings: An Optimization Approach

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Computers, Materials & Continua 2022年第4期71卷 439-455页

作者： Sultan H.almotiri Mohammed a.al Ghamdi Computer Science Department College of Computer and Information ScienceUmm AlQura UniversityMakkahKingdom of Saudi Arabia

The identification of an effective network which can efficiently meet the service requirements of the target,while maintaining ultimate performance at an increased level is significant and challenging in a fully interconnected wireless *** wrong selection can contribute to unwanted situations like frustrated users,slow service,traffic congestion issues,missed and/or interrupted calls,and wastefulness of precious network *** schemes estimate the handoff need and cause the network screening process by a single *** strategies are not effective enough because traffic characteristics,user expectations,network terminology and other essential device metrics are not taken into *** article describes an intelligent computing technique based on Multiple-Criteria Decision-Making(MCDM)approach developed based on integrated Fuzzy AHP-TOPSIS which ensures flexible usability and maximizes the experience of end-users in miscellaneous wireless *** different components the handover need is assessed and the desired network is ***,fuzzy sets provide effective solutions to address decision making problems where experts counter uncertainty to make a *** proposed research endeavor will support designers and developers to identify,select and prioritize best attributes for ensuring flexible usability in miscellaneous wireless *** results of this research endeavor depict that this proposed computational procedure would be the most conversant mechanism for determining the usability and experience of end-users.

关键词： Wireless sensor networks fuzzy logic AHP-TOPSIS miscellaneous network intelligent computing techniques

Arabic Sentiment a.alysis of Users’ Opinions of Governmental Mobile Applications

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Computers, Materials & Continua 2022年第9期72卷 4675-4689页

作者： Mohammed Hadwan Mohammed a.al-Hagery Mohammed al-Sarem Faisal Saeed Department of Information Technology College of ComputerQassim UniversityBuraydah51452Saudi Arabia Department of Computer Science College of Applied SciencesTaiz UniversityTaizYemen Inteligent a.alytic Group College of ComputerQassim UniversityBuraydah51452Saudi Arabia Department of Computer Science College of ComputerQassim UniversityBuraydah51452Saudi Arabia College of Computer Science and Engineering Taibah UniversityMedina42353Saudi Arabia Institute for Artificial Intelligence and Big Data Universiti Malaysia KelantanPengkalan ChepaKota Bharu16100KelantanMalaysia

Different types of pandemics that have appeared from time to time have changed many aspects of daily *** governments encourage their citizens to use certain applications to help control the spread of disease and to deliver other services during *** Saudi government has launched several mobile apps to control the pandemic and have made these apps available through Google Play and the app store.A huge number of reviews are written daily by users to express their opinions,which include significant information to improve these *** manual processing and extracting of information from users’reviews is an extremely difficult and time-consuming ***,the use of intelligent methods is necessary to a.alyse users’reviews and extract issues that can help in improving these *** research aims to support the efforts made by the Saudi government for its citizens and residents by a.alysing the opinions of people in Saudi Arabia that can be found as reviews on Google Play and the app store using sentiment a.alysis and machine learning *** the best of our knowledge,this is the first study to explore users’opinions about governmental apps in Saudi *** findings of this a.alysis will help government officers make the right decisions to improve the quality of the provided services and help application developers improve these applications by fixing potential issues that cannot be identified during application testing phases.A new dataset used for this research includes 8000 user reviews gathered from social media,Google Play and the app *** methods are applied to the dataset,and the results show that the k nearest neighbourhood(KNN)method generates the highest accuracy compared to other implemented methods.

关键词： Arabic sentiment a.alysis software quality user satisfaction improving online governmental services machine learning intelligent systems mobile app

Evolutionary relationship and species separation of four morphologically similar stichotrichous ciliates (Protozoa,Ciliophora)

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Progress in Natural Science:Materials International 2009年第5期19卷 581-586页

作者： John Clamp Khaled A.S.al-Rasheid Abdulaziz a.al-Khedhairy Department of Biology North Carolina Central University Zoology Department King Saud University

Phylogenetic and taxonomic studies on ciliate protists using molecular approaches have been demonstrated to be very reliable to form strong conclusions and results. In the present work, species separation of some morphologically similar stichotrichous ciliates, two species of Pseudokeronopsis and two species of Apokeronopsis, was reexamined using amplified ribosomal DNA restriction a.alysis (PCR-RFLP). Five of 10 restriction enzymes revealed species-specific polymorphic patterns, of which four similar stichotrichs could be significantly separated and identified. Among them, EcoR I offered almost no significantly different restriction fragment patterns, but the four species could be separated from one another and identified with Hae Ⅲ. Distinctly different restriction digestion haplotypes and simi-larity indices separated the species, and were used to construct a phylogeny. Phylogenies based on ITS2 nucleotide sequences and ITS2 secondary structures supported the separation of Pseudokeronopsis and Apokeronopsis using RFLP a.alysis, although three Pseudoker-onopsis carnea populations did not cluster together. In addition, phylogenetic a.alyses using multiple algorithms confirmed that these two genera formed two distinct groups within the urostylids.

关键词： Ciliophora Pseudokeronopsis Apokeronopsis PCR-RFLP ITS2 secondary structures