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Morphology of the ^(13)CO(3–2) millimetre emission across the gas disc surrounding the triple protostar GG Tau A using ALMA observations

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Research in Astronomy and Astrophysics 2018年第3期18卷 63-76页

作者： Nguyen Thi Phuong pham Ngoc Diep Anne Dutrey Edwige Chapillon Pierre Darriulat Stéphane Guilloteau Do Thi Hoai pham Tuyet Nhung Ya-Wen Tang Nguyen Thi Thao pham Tuan-Anh Department of Astrophysics Vietnam National Space CenterVietnam Academy of Science and Technology Graduate University of Science and Technology Vietnam Academy of Science and Technology Laboratoire d’Astrophysique de Bordeaux Université de Bordeaux IRAM F-38406 Saint Martin d’Hères Cedex Academia Sinica Institute of Astronomy and Astrophysics

Observations by the Atacama Large Millimetre/sub-millimetre Array of the dust continuum and ^13 CO（3–2） millimetre emissions of the triple stellar system GG Tau A are analysed,giving evidence for a rotating gas disc and a concentric and coplanar dust ring. The present work complements an earlier analysis（Tang et al.） by exploring detailed properties of the gas disc. A 95% confidence level upper limit of 0.24＂（34 au） is placed on the disc scale height at a distance of 1＂（140 au） from the central stars. Evidence for Keplerian rotation of the gas disc is presented,with the rotation velocity reaching-3.1 km s^-1 at 1＂ from the central stars,and a 99% confidence level upper limit of 9% is placed on relative contribution from a possible in-fall velocity. Variations of the intensity across the disc area are studied in detail and confirm the presence of a hot spot in the south-eastern quadrant. However several other significant intensity variations,in particular a depression in the northern direction,are also revealed. Variations of the intensity are found to be positively correlated to variations of the line width. Possible contributions to the measured line width are reviewed,suggesting an increase of the disc temperature and opacity with decreasing distance from the stars.

关键词： protoplanetary disks - stars low-mass - stars individual (GG Tau A)

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Occult persistence and lymphotropism of hepatitis C virus infection

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World Journal of Gastroenterology 2008年第18期14卷 2789-2793页

作者： Tram NQ pham Tomasz I Michalak Molecular Virology and Hepatology Research Group Division of BioMedical Sciences Faculty of Medicine Health Sciences Centre Memorial University St. John's NL A1B 3V6 Canada

Recent discovery of occult hepatitis C virus (HCV) infection persisting after spontaneous or antiviral therapy-induced resolution of hepatitis C was made possible by the introduction of nucleic acid amplification assays capable of detecting HCV RNA at sensitivities superseding those offered by clinical tests. Although individuals with this seemingly silent HCV infection are usually anti-HCV antibody reactive and have normal liver function tests, occult HCV infection has also been reported in anti-HCV-negative individuals with persistently elevated liver enzymes of unknown etiology. Studies have shown that HCV RNA can persist for years in serum, lymphomononuclear cells and liver in the absence of clinical symptoms, although histological evidence of a mild inflammatory liver injury can be occasionally encountered. Furthermore, while HCV RNA can be detected in circulating lymphoid cells in approximately 30% of cases, a short-term culture under stimulatory conditions augments HCV replication in these cells allowing detection of virus in otherwise HCV-negative cases. HCV infects different immune cell subsets, including CD4+ and CD8+ T lymphocytes, B cells and monocytes. Studies employing clonal sequencing and single-stranded conformational polymorphism analyses have revealed unique HCV variants residing in immune cells, further strengthening the notion of HCV lymphotropism. Overall, the data accumulated suggest that occult HCV infection is a common consequence of resolution of symptomatic hepatitis C and that examination of the cells of the immune system is an effective approach to diagnosis of HCV infection and its long-term persistence. Further work is required to fully realize pathogenic and epidemiological consequences of occult HCV persistence.

关键词： Hepatitis C virus Chronic hepatitis C Occul tviral persistence HCV lymphotropism Consequences of occult HCV persistence

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Rapid design of top-performing metal-organic frameworks with qualitative representations of building blocks

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npj Computational Materials 2023年第1期9卷 585-598页

作者： Yigitcan Comlek Thang Duc pham Randall Q.Snurr Wei Chen Department of Mechanical Engineering Northwestern UniversityEvanstonILUSA Department of Chemical and Biological Engineering Northwestern UniversityEvanstonILUSA

Data-driven materials design often encounters challenges where systems possess qualitative(categorical)***,representing Metal-organic frameworks(MOFs)through different building blocks poses a challenge for designers to incorporate qualitative information into design optimization,and leads to a combinatorial challenge,with large number of MOFs that could be *** this work,we integrated Latent Variable Gaussian Process(LVGP)and Multi-Objective Batch-Bayesian Optimization(MOBBO)to identify top-performing MOFs adaptively,autonomously,and *** showcased that our method(i)requires no specific physical descriptors and only uses building blocks that construct the MOFs for global optimization through qualitative representations,(ii)is application and property independent,and(iii)provides an interpretable model of building blocks with physical *** searching only~1%of the design space,LVGP-MOBBO identified all MOFs on the Pareto front and 97%of the 50 top-performing designs for the CO_(2) working capacity and CO_(2)/N2 selectivity properties.

关键词： properties qualitative autonomous

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Design of a Two-dimensional Recursive Filter Using the Bees Algorithm

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International Journal of Automation and computing 2010年第3期7卷 399-402页

作者： D.T.pham Ebubekir Koc Manufacturing Engineering Centre Cardiff University Cardiff CF24 3AA UK

This paper presents the first application of the bees algorithm to the optimisation of parameters of a two-dimensional （2D） recursive digital filter. The algorithm employs a search technique inspired by the foraging behaviour of honey bees. The results obtained show clear improvement compared to those produced by the widely adopted genetic algorithm （GA）.

关键词： Bees algorithm swarm intelligence optimisation two-dimensional digital filter design.

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Delivery methods for CRISPR/Cas9 gene editing in crustaceans

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Marine Life Science & Technology 2020年第1期2卷 1-5页

作者： Sen Xu Thinh Phu pham Swatantra Neupane Department of Biology University of Texas at Arlington501 S.Nedderman Dr.ArlingtonTX 76019USA

In this mini-review,we provide an up-to-date overview of the delivery methods that have been used for CRISPR/Cas9 genomic editing in crustacean *** embryonic microinjection as the main workforce for delivering CRISPR/Cas9 reagents,biologists working with crustacean species have to tackle the technical challenges involved in *** use examples of three Crustacean species(the branchiopod Daphnia,amphipod Parhyale hawaiensis,and decapod Exopalaemon carinicauda)to provide a technical guide for embryonic ***,we outline two potentially useful new techniques for delivering CRISPR/Cas9 components into crustaceans,i.e.,Receptor-Mediated Ovary Transduction of Cargo(ReMOT Control)and electroporation.

关键词： Microinjection Electroporation Vitellogenesis Daphnia Parhyale hawaiensis Exopalaemon carinicauda

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A novel memristive neural network with hidden attractors and its circuitry implementation

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Science China(Technological Sciences) 2016年第3期59卷 358-363页

作者： pham Viet Thanh JAFARI Sajad VAIDYANATHAN sundarapandian VOLOS Christos WANG Xiong School of Electronics and Telecommunications Hanoi University of Science and Technology Ol Dai Co Viet Hanoi Vietnam Biomedical Engineering Department Amirkabir University of Technology Tehran 15875-4413 Iran Research and Development Centre Vel Tech University Avadi Chennai-600062 Tamil Nadu India Physics Department Aristotle University of Thessaloniki GR-54124 Greece Institute for Advanced Study Shenzhen University Shenzhen 518060 China

Neural networks have been applied in various fields from signal processing, pattern recognition, associative memory to artifi- cial intelligence. Recently, nanoscale memristor has renewed interest in experimental realization of neural network. A neural network with a memristive synaptic weight is studied in this work. Dynamical properties of the proposed neural network are investigated through phase portraits, Poincar6 map, and Lyapunov exponents. Interestingly, the memristive neural network can generate hyperchaotic attractors without the presence of equilibrium points. Moreover, circuital implementation of such memristive neural network is presented to show its feasibility.

关键词： neural network memristor hyperchaos hidden attractor equilibrium

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Apply neural network for improving production planning at Samarang petrol mine

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International Journal of Intelligent Computing and Cybernetics 2016年第2期9卷 126-143页

作者： Quoc Trung pham Thi Kim Dung Phan School of Industrial Management HCMC University of TechnologyHo Chi Minh CityVietnam Schlumberger Information Solution Schlumberger Malaysia ServicesKuala LumpurMalaysia

Purpose-Artificial neural network(ANN)is considered a good solution for building non-linear relationship between input and output parameters,which is suitable for solving production back allocation,which is the most important step for production planning of petroleum *** purpose of this paper is to suggest a solution for solving production back allocation problem at Samarang petrol mine based on ANN ***/methodology/approach-In this study,well operational parameters’surveillance was conducted and ANN was used to build relationships between operation parameters and production *** method is used for testing and evaluating the possibility of using ANN for supporting production planning at Samarang ***-Consequently,the proposed ANN solution can increase the accuracy of predicted values and could be used for supporting production planning at Samarang *** ANN uses well test data for training and predicting(without adding new devices),it could be a feasible and cheap *** limitations/implications-There is a need for applying other methods,such as:support machine vector,non-linear autoregressive models,*** better evaluation of ANN *** implications-The ANN models helped operation engineers to understand well production performance and make decision to improve production plan in timely *** solution could be generalized for the whole mine or to similar petroleum mines in ***/value-This paper aims to propose a solution based on ANN for solving production back allocation problem of petroleum *** solution is tested at Samarang mine.

关键词： Malaysia Artificial neural network Petroleum industry Production back allocation Production plan Samarang mine

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A hierarchical system to predict behavior of soil and cantilever sheet wall by data-driven models

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Frontiers of Structural and Civil Engineering 2022年第6期16卷 667-684页

作者： Nang Duc BUI Hieu Chi PHAN Tiep Duc pham Ashutosh Sutra DHAR Institute of Techniques for Special Engineering Le Quy Don Technical UniversityHanoi 100000Vietnam Faculty of Engineering and Applied Science Memorial University of NewfoundlandSt.John’sNL A1B 3X5Canada

The study proposes a framework combining machine learning(ML)models into a logical hierarchical system which evaluates the stability of the sheet wall before other *** study uses the hardening soil(HS)model to develop a 200-sample finite element analysis(FEA)database,to develop the ML ***,a system containing three trained ML models is proposed to first predict the stability status(random forest classification,RFC)followed by 1)the cantilever top horizontal displacement of sheet wall(artificial neural network regression models,RANN1)and 2)vertical settlement of soil(RANN2).The uncertainty of this data-driven system is partially investigated by developing 1000 RFC models,based on the application of random sampling technique in the data splitting *** on the distribution of the evaluation metrics reveals negative skewed data toward the 1.0000 *** implies a high performance of RFC on the database with medians of accuracy,precision,and recall,on test set are 1.0000,1.0000,and 0.92857,*** regression ANN models have coefficient of determinations on test set,as high as 0.9521 for RANN1,and 0.9988 for RANN2,*** parametric study for these regressions is also provided to evaluate the relative insight influence of inputs to output.

关键词： finite element analysis cantilever sheet wall machine learning artificial neural network random forest

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Isogeometric analysis for free vibration of bidirectional functionally graded plates in the fluid medium

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Defence Technology（防务技术） 2022年第8期18卷 1311-1329页

作者： Quoc-Hoa pham Phu-Cuong Nguyen Van Ke Tran Trung Nguyen-Thoi Faculty of Civil Engineering Ho Chi Minh City Open UniversityHo Chi Minh CityViet Nam Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoiViet Nam Division of Computational Mathematics and Engineering Institute for Computational ScienceTon Duc Thang UniversityHo Chi Minh CityViet Nam Faculty of Civil Engineering Ton Duc Thang UniversityHo Chi Minh CityViet Nam

This paper for first time proposes an isogeometric analysis (IGA) for free vibration response of bi-directional functionally graded (BDFG) rectangular plates in the fluid medium. Material properties of the BDFG plate change in both the thickness and length directions via power-law distributions and Mori-Tanaka model. The governing equation of motion of BDFG plate in the fluid-plate system is formulated basing on Hamilton's principle and the refined quasi three-dimensional (3D) plate theory with improved function f(z). The fluid velocity potential is derived from the boundary conditions of the fluid-plate system and is used to determine the added mass. The discrete system of equations is derived from the Galerkin weak form and numerically analyzed by IGA. The accuracy and reliability of the proposed solutions are verified by comparing the obtained results with those published in the literature. Moreover, the effects of the various parameters such as the interaction boundary condition, geometric parameter, submerged depth of plate, fluid density, fluid level, and the material volume control coefficients on the free vibration behavior of BDFG plate in the fluid medium are investigated in detail. Some major findings regarding the numerical results are withdrawn in conclusions.

关键词： Contact plate-fluid Refined quasi 3D plate theory Mori-Tanaka model Isogeometric analysis Bidirectional functionally graded plate

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A hybrid machine learning model to estimate self-compacting concrete compressive strength

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Frontiers of Structural and Civil Engineering 2022年第8期16卷 990-1002页

作者： Hai-Bang LY Thuy-Anh NGuyen Binh Thai pham May Huu NGuyen Civil Engineering Department University of Transport TechnologyHanoi 100000Vietnam Civil and Environmental Engineering Program Graduate School of Advanced Science and EngineeringHiroshima UniversityHiroshima 739-8527Japan

This study examined the feasibility of using the grey wolf optimizer(GWO)and artificial neural network(ANN)to predict the compressive strength(CS)of self-compacting concrete(SCC).The ANN-GWO model was created using 115 samples from different sources,taking into account nine key SCC *** validation of the proposed model was evaluated via six indices,including correlation coefficient(R),mean squared error,mean absolute error(MAE),IA,Slope,and mean absolute percentage *** addition,the importance of the parameters affecting the CS of SCC was investigated utilizing partial dependence *** results proved that the proposed ANN-GWO algorithm is a reliable predictor for SCC’s *** that,an examination of the parameters impacting the CS of SCC was provided.

关键词： artificial neural network grey wolf optimize algorithm compressive strength self-compacting concrete

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