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An Efficient Adaptive Hierarchical Sliding Mode Control Strategy Using Neural Networks for 3D Overhead Cranes

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International Journal of Automation and computing 2019年第5期16卷 614-627页

作者： viet-anh Le hai-Xuan Le Linh Nguyen Minh-Xuan Phan Department of Automatic Control Hanoi University of Science and TechnologyHanoi 10000Vietnam Centre for Autonomous Systems University of Technology SydneyNew South Wales 2007Australia

In this paper, a new adaptive hierarchical sliding mode control scheme for a 3D overhead crane system is proposed. A controller is first designed by the use of a hierarchical structure of two first-order sliding surfaces represented by two actuated and un-actuated subsystems in the bridge crane. Parameters of the controller are then intelligently estimated, where uncertain parameters due to disturbances in the 3D overhead crane dynamic model are proposed to be represented by radial basis function networks whose weights are derived from a Lyapunov function. The proposed approach allows the crane system to be robust under uncertainty conditions in which some uncertain and unknown parameters are highly difficult to determine. Moreover, stability of the sliding surfaces is proved to be guaranteed. Effectiveness of the proposed approach is then demonstrated by implementing the algorithm in both synthetic and reallife systems, where the results obtained by our method are highly promising.

关键词： 3D overhead crane adaptive control hierarchical sliding mode control neural network radial basis function

Improved knowledge-based neural network(KBNN)model for predicting spring-back angles in metal sheet bending

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International Journal of Modeling, Simulation, and Scientific Computing 2014年第2期5卷 65-91页

作者： Tinh Quoc Bui anh viet Tran Abid Ali Shah Department of Civil Engineering University of Siegen Paul-Bontz-Str.9-1157076 SiegenGermany School of Mechanical and Automotive Engineering University of Ulsan San 29Mugeo 2-dong NamguP.O.Box 18UlsanSouth Korea

We develop an efficiently improved knowledge-based neural network(KBNN)associated with optimization algorithms and finite element analysis(FEA)to accurately predict spring-back angles in metal sheet *** well-known V and U prevalent processes of bending are *** KBNN predictive results are based on the empirical model and artificial neural network(ANN)*** empirical model is constructed from the FEA results using response surface method,while the multilayer perceptron is employed to create the *** trained KBNN can accurately model the relation-ship between the spring-back angles and process *** obtained results are validated against other existing methods showing a high accuracy.

关键词： Metal sheet bending spring-back angles knowledge-based neural network genetic algorithm optimization algorithm

Intermetallic Evolution of Al–Si-Coated Hot Stamping Steel During Modified Electrically Assisted Rapid Heating

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Acta Metallurgica Sinica(English Letters) 2018年第12期31卷 1327-1333页

作者： Kieu-anh Dinh Sung-Tae Hong Tien viet Luu Moon-Jo Kim Heung Nam han School of Mechanical Engineering University of Ulsan Liquid Processing & Casting R&D Group Korea Institute of Industrial Technology Department of Materials Science and Engineering RIAMSeoul National University

Modified electrically assisted(EA) rapid heating of Al–Si-coated hot stamping steel is suggested, and the intermetallic evolution in the coating during heating is experimentally investigated. In the modified EA rapid heating, a continuous electric current for a suitable duration is applied to a specimen to heat it to a temperature slightly below the melting temperature of the coating. The temperature of the specimen is then kept constant for a specified dwell time. The result of the microstructural analysis shows that the modified EA rapid heating could effectively increase the thickness of the intermetallic layer between the coating and steel substrate much faster than conventional furnace heating and induction heating. The effectiveness of EA rapid heating may be due to the athermal effect of the electric current on the mobility of atoms, in addition to the well-known resistance heating effect. EA rapid heating also provides a technical advantage in that partial austenization can be easily achieved by properly placing the electrodes, as demonstrated in the present study.

关键词： Hot stamping Electrically assisted rapid heating Partial austenization Al–Si-coated hot stamping steel

STRONG CONVERGENCE OF AN INERTIAL EXTRAGRADIENT METHOD WITH AN ADAPTIVE NONDECREASING STEP SIZE FOR SOLVING VARIATIONAL INEQUALITIES

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Acta Mathematica Scientia 2022年第2期42卷 795-812页

作者： Nguyen Xuan LINH Duong viet THONG Prasit CHOLAMJIAK Pham anh TUAN Luong Van LONG Department of Mathematics Mathematics Falcuty of Information TechnologyNational University of Civil Engineering Division of Applied Mathematics Thu Dau Mot UniversityBinh Duong ProvinceVietnam School of Science University of PhayaoPhayao 56000Thailand Paculty of Mathematical Economics National Economics UniversityHanoi CityVietnam

In this work,we investigate a classical pseudomonotone and Lipschitz continuous variational inequality in the setting of Hilbert space,and present a projection-type approximation method for solving this *** method requires only to compute one projection onto the feasible set per iteration and without any linesearch procedure or additional projections as well as does not need to the prior knowledge of the Lipschitz constant and the sequentially weakly continuity of the variational inequality mapping.A strong convergence is established for the proposed method to a solution of a variational inequality problem under certain mild ***,we give some numerical experiments illustrating the performance of the proposed method for variational inequality problems.

关键词： Inertial method Tseng’s extragradient viscosity method variational inequality problem pseudomonotone mapping strong convergence

Development of a PARCS/Serpent model for neutronics analysis of the Dalat nuclear research reactor

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Nuclear Science and Techniques 2021年第2期32卷 32-44页

作者： viet-Phu Tran Kien-Cuong Nguyen Donny hartanto Hoai-Nam Tran Vinh Thanh Tran Van-Khanh Hoang Pham Nhu viet ha Institute for Nuclear Science and Technology(INST) Vietnam Atomic Energy Institute(VINATOM)179 Hoang Quoc Viet str.Cau Giay DistrictHanoi 100000Vietnam Nuclear Research Institute(NRI) Vietnam Atomic Energy Institute(VINATOM)01 Nguyen Tu LucDalatLamdong 670000Vietnam Department of Mechanical and Nuclear Engineering University of SharjahPO.BOX 27272SharjahUnited Arab Emirates Institute of Fundamental and Applied Sciences Duy Tan UniversityHo Chi Minh city 700000Vietnam Faculty of Natural Science Duy Tan UniversityDanang 550000Vietnam Nuclear Safety Division Technical Support Center for Radiation and Nuclear Safety and Emergency ResponseVietnam Agency for Radiation and Nuclear Safety(VARANS)113 Tran Duy Hung str.Cau Giay DistrictHanoi 100000Vietnam

Cross-sectional homogenization for full-core calculations of small and complex reactor configurations,such as research reactors,has been recently recognized as an interesting and challenging *** paper presents the development of a PARCS/Serpent model for the neutronics analysis of a research reactor type TRIGA Mark-II loaded with Russian VVR-M2 fuel(known as the Dalat Nuclear Research Reactor or DNRR).The full-scale DNRR model and a supercell model for a shim/safety rod and its surrounding fuel bundles with the Monte Carlo code Serpent 2 were proposed to generate homogenized fewgroup cross sections for full-core diffusion calculations with *** full-scale DNRR model with Serpent 2 was also utilized as a reference to verify the PARCS/Serpent *** of the effective neutron multiplication factors,radial and axial core power distributions,and control rod worths showed a generally good agreement between PARCS and Serpent *** addition,the discrepancies between the PARCS and Serpent 2 results are also ***,the results indicate the applicability of the PARCS/Serpent model for further steady state and transient analyses of the DNRR.

关键词： PARCS Serpent 2 Group constant DNRR

A tree-based intelligence ensemble approach for spatial prediction of potential groundwater

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International Journal of Digital Earth 2020年第12期13卷 1408-1429页

作者： Mohammadtaghi Avand Saeid Janizadeh Dieu Tien Bui viet Hoa Pham Phuong Thao T.Ngo viet-ha Nhu Faculty of Natural Resources and Marine Sciences Tarbiat Modares UniversityTehranIran Geographic Information Science Research Group Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Environment and Labour Safety Ton Duc Thang UniversityHo Chi Minh CityVietnam Ho Chi Minh City Institute of Resources Geography Vietnam Academy of Science and TechnologyHo Chi Minh CityVietnam Institute of Research and Development Duy Tan UniversityDa NangVietnam Department of Geological-Geotechnical Engineering Hanoi University of Mining and GeologyHanoiVietnam

The objective of this research is to propose and confirm a new machine learning approach of Best-First tree(BFtree),AdaBoost(AB),MultiBoosting(MB),and Bagging(Bag)ensembles for potential groundwater mapping and assessing role of influencing *** Yasuj-Dena area(Iran)is selected as a case *** this regard,a Yasuj-Dena database was established with 362 springs locations and 12 groundwater-influencing factors(slope,aspect,elevation,stream power index(SPI),length of slope(LS),topographic wetness index(TWI),topographic position index(TPI),land use,lithology,distance from fault,distance from river,and rainfall).The database was employed to train and validate the proposed groundwater *** area under the curve(AUC)and statistical metrics were employed to check and confirm the quality of the *** result shows that the BFTree-Bag model(AUC=0.810,kappa=0.495)has the highest prediction performance,followed by the BFTree-MB model(AUC=0.785,kappa=0.477),and the BFTree-MB model(AUC=0.745,kappa=0.422).Compared to the benchmark of Random Forests,the BFTree-Bag model performs better;therefore,we conclude that the BFtree-Bag is a new tool should be used for modeling of groundwater potential.

关键词： Environmental modeling groundwater potential GIS ensemble model decision tree

Comparative Chemical Research in Essential Oils from Six Apiaceae Species Growing in the Northern Region of vietnam

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1677-1687页

作者： Nguyen Quang Hung Nguyen Thanh Tung Nguyen Phuong Hanh Chu Thi Thu ha Nguyen Thi Nhung Nguyen Thai An Vu Xuan Giang Luong Van hao Oleh Koshovyi Ain Raal Institute of Ecology and Biological Resources Vietnam Academy of Science and Technology(VAST)Cau GiayHa Noi100000Viet Nam Graduate University of Science and Technology Vietnam Academy of Science and Technology(VAST)Cau GiayHa Noi100000Viet Nam Department of Pharmacognosy Faculty of Pharmacognosy and Traditional MedicineHanoi University of PharmacyHoan KiemHa Noi100000Viet Nam Sa Pa Research Center of Medicinal Materials National Institute of Medicinal MaterialsDien Bien PhuSa PaLao Cai330000Viet Nam Institute of Pharmacy Faculty of MedicineUniversity of TartuTartu50411Estonia

Our study aimed to compare the essential oil(EO)concentration and composition of several Apiaceae species growing in the Northern region of *** yields of EOs from materials ranged from 0.03%(root EO of Angelica acutiloba and aerial parts EO of Heracleum bivittatum)-0.27%(leaf EO of Xyloselinum vietnamense).Gas chromatography-mass spectrometry(GC-MS)allowed the identiﬁcation of 74 components in the EOs of six Apiaceae species,making up 94.4%–100.0%of the *** EO from Angelica acutiloba,(Z)-ligustilide accounted for an extremely large proportion(94.9%).EO of Angelica pubescens was dominated by six character-istic components includingα-pinene(21.5%),β-phellandrene(18.1%),p-cymene(12.2%),3-methylnonane(8.7%),o-cymene(8.1%),and D-sylvestrene(6.2%).The EO from Cryptotaenia japonica was characterized by high amounts ofα-selinene(48.7%),β-selinene(23.7%),and trans-β-farnesene(5.4%).The EOs from leaves and stems of Xyloselinum vietnamense were characterized by high concentrations of sabinene(69.8%and 33.8%),4-terpineol(8.7%and 7.4%)andβ-pinene(4.0%and 6.5%)while EOs from aerial parts and root of Xylo-selinum leonidii comprise four characteristic monoterpenes includingα-pinene(28.2%and 52.8%),β-pinene(7.9%and 10.3%),β-phellandrene(7.6%and 15.3%),and sabinene(3.0%and 4.1%).Additionally,cryptone is also one of the major components in the EO of Xyloselinum leonidii(13.2%in the aerial parts oil and 2.8%in the root oil).In the EOs isolated from the aerial parts and root of Heracleum bivittatum,α-pinene(22.5%and 70.2%)andβ-pinene(43.2%and 20.0%)were the predominant *** appeared in the EO from aerial parts of Heracleum bivittatum with a relatively high concentration(13.5%)while bornyl acetate(5.1%)was also one of the main components in the EO from its aerial parts but was not detected in other Apiaceae species in the present *** databases help identify and control the quality of plant material studied from the family Apiaceae growing in vietnam.

关键词： Apiaceae essential oil terpenoids gaschromatography-mass spectrometry

Studies on sustainable features of vernacular architecture in different regions across the world:A comprehensive synthesis and evaluation

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Frontiers of Architectural Research 2019年第4期8卷 535-548页

作者： anh Tuan Nguyen Nguyen Song ha Truong David Rockwood anh Dung Tran Le Faculty of Architecture the University of Danang-University of Science and TechnologyDa NangViet Nam School of Architecture University of Hawaii at ManoaUSA Laborotoire des Technologies Innovantes(LTI) Universite de Picardie Jules VerneFrance

Due to the increasing pressure brought by recent global environmental problems,building designers are embracing regionalism and the knowledge of traditional structures,arguing that these structures are energy efficient and highly *** observe clear evidence of the increasing interest in vernacular architecture among the research *** study therefore aims to clarify the contents and issues raised in the studies on vernacular architecture and the knowledge and recommendations that can be derived from them.A database of the research is established by collecting many studies from primary *** data is carefully refined and categorized into a table where synthesized information is *** results of this study show an uneven geographic and climatic distribution of the studies;the trend in selecting research objectives and research objects;the choice of research methods with a clear shift towards quantitative research methods,and the generic findings from the database of the *** results can support diverse inquiries about vernacular architecture across the world and be used as a resource or an orientation to support numerous subsequent studies.

关键词： Vernacular architecture Traditional architecture Sustainable feature Research method Building design

LiMn_2O_4/CNTs and LiNi_(0.5)Mn_(1.5)O_4/CNTs Nanocomposites as High-Performance Cathode Materials for Lithium-Ion Batteries

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Acta Metallurgica Sinica(English Letters) 2015年第1期28卷 122-128页

作者： Thang Van Le ha Tran Nguyen anh Tuan Luu Man Van Tran Phung Loan My Le Faculty of Materials Technology Ho Chi Minh University of Technology 268 Ly Thuong Kiet Ward 14 District 10 Ho Chi Minh City Vietnam Department of Physical Chemistry University of Science VNUHCM 227 Nguyen Van Cu Street District 5 Ho Chi Minh CityVietnam

The demand of higher energy density and higher power capacity of lithium（Li）-ion secondary batteries has led to the search for electrode materials whose capacities and performance are better than those available today. Carbon nanotubes（CNTs）, with their unique properties such as 1D tubular structure, high electrical and thermal conductivities, and extremely large surface area, have been used as materials to prepare cathodes for Li-ion batteries. The structure and morphology of CNTs were analyzed by X-ray diffraction（XRD）, scanning electron microscopy（SEM）, and transmission electron microscopy（TEM）. The functional groups on the purified CNT surface such as –COOH, –OH were characterized by Fourier Transform infrared spectroscopy. The electrode materials were fabricated from LiMn2O4（LMO）, doped spinel LiNi0.5Mn1.5O4, and purified CNTs via solid-state reaction. The structure and morphology of the electrode were characterized using XRD, SEM, and TEM. Finally, the efficiency of the electrode materials using CNTs was evaluated by cyclic voltammetry and electrochemical impedance spectroscopy.

关键词： Nanocomposites Carbon nanotubes(CNTs) Spinel materials Lithium-ion batteries(LIBs)