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Acta Mathematica Sinica,English Series 2022年第12期38卷 2199-2219页

作者： Nguyen Duc PHUONG le dinh long Anh Tuan NGUYEN Dumitru BAleANU Faculty of Fundamental Science Industrial University of Ho Chi Minh CityVietnam Division of Applied Mathematics Science and Technology Advanced InstituteVanLang UniversityHoChi Minh CityVietnam Faculty of Technology Van Lang UniversityHo Chi Minh CityVietnam Department of Mathematics Cankaya UniversityAnkaraTurkey lebanese AmericanUniversity BeirutLebanon Institute of Space Sciences Magurele-BucharestRomania

This paper is devoted to identifying an unknown source for a time-fractional diffusion equation in a general bounded ***,we prove the problem is non-well posed and the stability of the source ***,by using the Modified Fractional Landweber method,we present regularization solutions and show the convergence rate between regularization solutions and sought solution are given under a priori and a posteriori choice rules of the regularization parameter,***,we present an illustrative numerical example to test the results of our theory.

关键词： Source problem fractional pseudo-parabolic problem ill-posed problem convergence estimates regularization

A Comprehensive Survey of Recent Transformers in Image,Video and Diffusion Models

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Computers, Materials & Continua 2024年第7期80卷 37-60页

作者： dinh Phu Cuong le Dong Wang Viet-Tuan le College of Computer Science and Electronic Engineering Hunan UniversityChangsha410082China Faculty of Information Technology Yersin University of Da LatDa Lat66100Vietnam Faculty of Information Technology Ho Chi Minh City Open UniversityHo Chi Minh City722000Vietnam

Transformer models have emerged as dominant networks for various tasks in computer vision compared to Convolutional Neural Networks(CNNs).The transformers demonstrate the ability to model long-range dependencies by utilizing a self-attention *** study aims to provide a comprehensive survey of recent transformerbased approaches in image and video applications,as well as diffusion *** begin by discussing existing surveys of vision transformers and comparing them to this ***,we review the main components of a vanilla transformer network,including the self-attention mechanism,feed-forward network,position encoding,*** the main part of this survey,we review recent transformer-based models in three categories:Transformer for downstream tasks,Vision Transformer for Generation,and Vision Transformer for *** also provide a comprehensive overview of recent transformer models for video tasks and diffusion *** compare the performance of various hierarchical transformer networks for multiple tasks on popular benchmark ***,we explore some future research directions to further improve the field.

关键词： Transformer vision transformer self-attention hierarchical transformer diffusion models

Influence of different land-use types on selected soil properties related to soil fertility in A Luoi District,Thua Thien Hue,Vietnam

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Soil Ecology letters 2024年第1期6卷 131-140页

作者： Khoa Phuc Nguyen Tan Trong Tran Huy dinh le Phuong Thuy Nguyen Hien Thao Thi Pham Dien Thanh Nguyen Ngu Huu Nguyen University of Agriculture and Forestry Hue UniversityHue CityThua Thien Hue 52000Vietnam School of Biotechnology Tan Tao UniversityTan Duc ECityDuc HoaLong An850000Vietnam

Land use type affects the physicochemical properties of *** value of OM and TN is high in acacia *** acidity of soil is considered a serious constraint for *** cash crops are acacia,cassava,banana,rice and *** fertility is affected by land-use types and land management,which exacerbates soil erosion and various other forms of soil degradation in the mountainous regions of *** study was conducted in A Luoi District,Thua Thien Hue,Vietnam to identify the effects of land-use types on specific soil physicochemical characteristics related to soil *** physicochemical properties,such as organic matter(OM),total nitrogen(TN),total phosphorous(TP),and K+were significantly affected by land-use *** results showed that the soils were sandy in rice but clay loam for acacia and *** mean bulk density value of acacia soil was significantly greater than that of other *** were higher in the acacia soils than those in the rice,maize,and banana *** OM content was significantly higher in the acacia,cassava,and banana soils than those in the rice and maize *** mean of exchangeable K+in the rice soil was higher compared to those in other soils and was affected by land-use *** high exchangeable acidity content in the soils was probably due to intensive ***,both land use type and management did not affect the CEC ***,the inappropriate land use caused the disturbance of soil physicochemical properties,indicating that the conditions of rice and maize soils are becoming worse than acacia ***,lowering the intensity of cultivation,adopting incorporated soil fertility management,and applying organic fertilizer should preserve the existing conditions and enhance soil properties.

关键词： Land-use types soil characteristics soil frility suitable crop Vietnam

A novel approach for synthesis of hierarchical mesoporous Nd2O3 nanomaterials

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Journal of Rare Earths 2017年第7期35卷 677-682页

作者： le Huu Trinh dinh Quang Khieu Hoang Thai long Tran Thai Hoa Duong Tuan Quang Nguyen Duc Cuong College of Sciences Hue University 77 Nguyen Hue Hue City Viet Nam Faculty of Hospitality and Tourism Hue University 22 Lam Hoang Hue CityViet Nam College of Education Hue University 34 Le LoL Hue City Viet Nam

A novel route to the fabrication of hierarchical mesoporous Nd_2O_3 nanostructures including nanospheres and nanoporous network was described. Their structure and morphology evolution of the as-synthesized materials were determined by various techniques such as scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy, Fourier transforminfrared spectra, nitrogen adsorption/desorption isotherm, and a formation mechanism was proposed. The results revealed that the Nd_2O_3 nanospheres had the diameter of 300 nm, which were composed of small primary nanoparticles（NPs） with the size of 10 nm. The nanoporous structure also formed the NPs of ca. 10 nm which were connected with each other to form a three-dimensional（3D） texture. This simple and mild approach to fabricate hierarchical mesoporous Nd_2O_3 nanostructures could be easily scaled up and potentially extended to synthesize other oxide hierarchical structures.

关键词： Nd2O3 hierarchical nanostructures nanospheres nanoporous network rare earths

Effect of thinning intensity on tree growth and temporal variation of seed and cone production in a Pinus koraiensis plantation

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Journal of Forestry Research 2019年第3期30卷 835-845页

作者： Thanh Tuan Nguyen dinh Tien Tai Peng Zhang Muhammad Razaq Hai-long Shen School of Forestry Northeast Forestry University Harbin 150040People’s Republic of China Department of Forestry Vietnam Forestry University-Second CampusOkayamaDongnai 810000Vietnam Graduate School of Environmental and Life Science Okayama UniversityOkayamaJapan

Thinning of Korean pine (Pinus koraiensis Sieb. et Zucc.) is used to facilitate timber and cone production. The present study in Northeast China investigated the effects of thinning intensity on individual tree growth, temporal variation in cone yield, and seed quality in Korean pine plantation. In 2005, five thinning intensity levels (none, extreme, heavy, moderate and light) were set in 15 permanent plots in a 32-year-old Korean pine plantation at Mengjiagang Forest Farm, Jiamusi City, Heilongjiang Province. We recorded tree growth and seed cone production from 2013 to 2016, i.e., from 8 to 11 years after thinning. Except for height growth, thinning increased tree growth (diameter at breast height and crown size) and improved cone yield. The extreme thinning treatment (to 300 trees per hectare) resulted in the largest tree diameter, tree volume, crown size and 4-year cone production per tree. The highest cone yield per tree in the mast year (2014) was observed when stands were thinned to 500 trees per hectare (heavy thinning). Although the best cone and seed quality and the largest cone and seed mass per tree were recorded in the heavily thinned stand, no significant differences were found between heavy and moderate thinning stands (750 trees per hectare). At the stand level, the moderately thinned stand had the highest basal area, stock volume and seed cone production per stand. Our results suggest that thinning to 750 trees per hectare will improve timber and cone productivity in 40-year-old P. koraiensis stands.

关键词： Korean pine Thinning intensity Seed yield Tree growth Temporal variation in cone yield

Formability improvement and blank shape definition for deep drawing of cylindrical cup with complex curve profile from SPCC sheets using FEM

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Journal of Central South University 2014年第1期21卷 27-34页

作者： Duc-Toan Nguyen Duy-Khoe dinh Hong-Minh Thi Nguyen Tien-long Banh Young-Suk Kim School of Mechanical Engineering Hanoi University of Science and Technology1A-Dai Co Viet StreetHai Ba Trung DistrictHanoi CityVietnam Department of Mechanical Engineering Hungyen University of Technology and EducationHungyenVietnam Department of Mechanical Engineering Kyungpook National University1370 SangyeokBuk-kuDaegu 702-701Korea

In the current work, to predict and improve the formability of deep drawing process for steel plate cold rolled commercial grade （SPCC） sheets, three parameters including the blanking force, the die and punch comer radius were considered. The experimental plan according to Taguchi＇s orthogonal array was coupled with the finite element method （FEM） simulations. Firstly, the data from the test of stress-strain and forming limit curves were used as input into ABAQUS/Explicit finite element code to predict the failure occurrence of deep drawing process. The three parameters were then validated to establish their effects on the press formability. The optimum case found via simulation was finally confirmed through an experiment. In order to obtain the complex curve profile of cup shape after deep drawing, the anisotropic behavior of earring phenomenon was modeled and implemented into FEM. After such phenomenon was correctly predicted, an error metric compared with design curve was then measured.

关键词： finite element method SPCC deep-drawing forming limit diagram criterion Taguchi's method earring prediction

Superhydrophobic self-extinguishing cotton fabrics for electromagnetic interference shielding and human motion detection

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Journal of Materials Science & Technology 2023年第1期132卷 59-68页

作者： lei Liu Zhewen Ma Menghe Zhu Lina Liu Jinfeng Dai Yongqian Shi Jiefeng Gao Toan dinh Thanh Nguyen long-Cheng Tang Pingan Song College of Environment and Safety Engineering Qingdao University of Science and TechnologyQingdao 266061China School of Chemistry and Materials Engineering Zhejiang A&F UniversityHangzhou 311300China College of Environment and Safety Engineering Fuzhou UniversityFuzhou 350116China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Centre for Future Materials University of Southern QueenslandSpringfield 4300Australia School of Engineering University of Southern QueenslandSpringfield 4300Australia College of Material Chemistry and Chemical EngineeringKey Laboratory of Organosilicon Chemistry and Material Technology of MoEHangzhou Normal UniversityHangzhou 311121China School of Agriculture and Environmental Science University of Southern QueenslandSpringfield 4300Australia

Multifunctional intelligent fire-safe cotton fabric promises next-generation fire-fighting uniform and sen-sor ***,cotton fabrics’hygroscopicity and intrinsic flammability significantly impede their potential applications in ***,we report a superhydrophobic fireproof cotton fabric(PEI-APP-PEI-MXene)generated via sequential layer-by-layer deposition of polyethyleneimine(PEI),am-monium polyphosphate(APP),and titanium carbide(MXene),followed by hydrophobic treatment with silicone *** to untreated cotton,the treated cotton fabric with 10 polymolecular layers exhibits∼43%and∼42%reductions in the peak heat release rate and total heat release,respectively,a desired UL-94 V-0 rating,and a high limiting oxygen index(LOI)value of 39.5 vol.%.In addition to that,the treated fabrics displayed improved electromagnetic interference(EMI)shielding and motion-sensing *** presented work provides a facile and effective surface modification approach to generate multifunctional cotton fabrics with promising practical applications.

关键词： Cotton fabric Super-hydrophobicity Flame retardancy Electromagnetic interference shielding Motion sensor MXene

Morphological Change in the Northern Red River Delta,Vietnam

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Journal of Ocean University of China 2018年第6期17卷 1272-1280页

作者： BUI Vuong Van FAN Daidu NGUYEN Dac Ve TRAN dinh Lan TRAN Duc Thanh HOANG Van long NGUYEN Thi Hong Hanh Institute of Marine Environment and Resources Vietnam Academy of Science and TechnologyHaiphong 18000Vietnam State Key Laboratory of Marine Geology Tongji UniversityShanghai 200092China Hanoi University of Mining and Geology Hanoi 10000Vietnam Graduate University of Science and Technology Vietnam Academy of Science and TechnologyHanoi 10000Vietnam

Coastal erosion has become a worldwide concern, typically in the densely populated Asian mega-river deltas. Severe coastal erosion in the southern Red River Delta(RRD) has been intensively studied. Coastal morphological change in the northern RRD was examined in detail through DEM(Digital Elevation Model) analysis based on time series of bathymetrical maps(1965–2004) and Landsat images(1975–2015) in this study. The results show that the northern RRD is featured by rapid coastal accretion in the past few decades, although suspended sediment flux has dropped by roughly 60% after the completeness of Hoa Binh Dam(HBD) in 1988 and relative sea level rose at 1.9 mm yr^(-1). However, accretion at the outer part of subtidal shoals and platforms was observed to slow down quickly or even turned into erosion in the last two decades. The resuspended sediments from the erosion zone can be transported landward to replenish the inner coastal zone, keeping the latter accretion in the near future to compensate for the sediment discharge decrease from the river. However, this lag effect should be terminated soon if other adverse effects go worse, e.g., damming rivers, sea-level rising, strengthening storms, land reclamation and other poor-designed coastal engineering. Coastal planners and managers should pay full attention to these changes.

关键词： Morphological change DEM coastal erosion coastal engineering coastal management tide-dominated Red River Delta

A Novel Incremental Attribute Reduction Algorithm Based on Intuitionistic Fuzzy Partition Distance

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Computer Systems Science & Engineering 2023年第12期47卷 2971-2988页

作者： Pham Viet Anh Nguyen Ngoc Thuy Nguyen long Giang Pham dinh Khanh Nguyen The Thuy Graduate University of Science and Technology Vietnam Academy of Science and TechnologyHanoi100000Vietnam Institute of Information Technology Vietnam Academy of Science and TechnologyHanoi100000Vietnam HaUI Institute of Technology Hanoi University of IndustryHanoi100000Vietnam Faculty of Information Technology University of SciencesHue UniversityHue530000Vietnam AI Research Department Neurond Technology JSCHanoi100000Vietnam Information and Communication Technology Center Department of Information and CommunicationsBacninh790000Vietnam

Attribute reduction,also known as feature selection,for decision information systems is one of the most pivotal issues in machine learning and data *** based on the rough set theory and some extensions were proved to be efficient for dealing with the problemof attribute ***,the intuitionistic fuzzy sets based methods have not received much interest,while these methods are well-known as a very powerful approach to noisy decision tables,i.e.,data tables with the low initial classification ***,this paper provides a novel incremental attribute reductionmethod to dealmore effectivelywith noisy decision tables,especially for highdimensional *** particular,we define a new reduct and then design an original attribute reduction method based on the distance measure between two intuitionistic fuzzy *** should be noted that the intuitionistic fuzzypartitiondistance iswell-knownas aneffectivemeasure todetermine important *** interestingly,an incremental formula is also developed to quickly compute the intuitionistic fuzzy partition distance in case when the decision table increases in the number of *** formula is then applied to construct an incremental attribute reduction algorithm for handling such dynamic ***,some experiments are conducted on real datasets to show that our method is far superior to the fuzzy rough set based methods in terms of the size of reduct and the classification accuracy.

关键词： Incremental attribute reduction intuitionistic fuzzy sets partition distance measure dynamic decision tables

A General Equilibrium Model for Energy Policy Evaluation Using GTAP-E for Vietnam

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Economics World 2014年第5期2卷 347-355页

作者： Do dinh long Suduk Kim Thai Nguyen University of Economics and Business Administration (TUEBA) Thai Nguyen Vietnam Ajou University Suwon Korea

In the past several years, there has been growing concern on the scarcity of energy resources, the volatility of energy prices, and the impact of energy sector on climate change. In this context, energy-environment models designed for analysis of energy systems have become more important. In this paper, a Computable General Equilibrium Model （CGE） using an energy-environmental version of Global Trade Analysis Project （GTAP） model （known as GTAP-E） for Vietnam is presented based on the GTAP Data Base version 7. The model is developed following the original structure and the revised version of the GTAP-E model. This model is used to simulate the adoption of carbon tax for Vietnam for the base year of 2004. The economy-level and detailed sector-specific effects are also examined considering energy intensive and non-intensive sectors. Simulation results show the negative influences of different carbon tax scenarios to Vietnam＇s economy. The results would also indicate the potential of carbon taxation as a driving force for the mitigation of carbon dioxide and for new and renewable energy promotion in Vietnam. In fact, this study is the first simulation exercise of energy-environmental policy for the Vietnamese case.

关键词： Computable General Equilibrium Model (CGE) Global Trade Analysis Project (GTAP) GTAP-E carbon tax energy CO2 emission Vietnam