检索结果-南通市图书馆

Random vibration analysis of FGM plates subjected to moving load using a refined stochastic finite element method

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第4期34卷 42-56页

作者： Ngoc-Tu Do Trung thanh tran Faculty of Mechanical Engineering Hanoi University of IndustryHanoiViet Nam Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoiViet Nam

The article introduces a finite element procedure using the bilinear quadrilateral element or four-node rectangular element(namely Q4 element) based on a refined first-order shear deformation theory(rFSDT) and Monte Carlo simulation(MCS), so-called refined stochastic finite element method to investigate the random vibration of functionally graded material(FGM) plates subjected to the moving *** advantage of the proposed method is to use r-FSDT to improve the accuracy of classical FSDT, satisfy the stress-free condition at the plate boundaries, and combine with MCS to analyze the vibration of the FGM plate when the parameter inputs are random quantities following a normal distribution. The obtained results show that the distribution characteristics of the vibration response of the FGM plate depend on the standard deviation of the input parameters and the velocity of the moving ***, the numerical results in this study are expected to contribute to improving the understanding of FGM plates subjected to moving loads with uncertain input parameters.

关键词： FGM Moving load R-FSDT Q4 element Monte Carlo simulation Random vibration

GLOBAL BOUND ON THE GRADIENT OF SOLUTIONS TO p-LAPLACE TYPE EQUATIONS WITH MIXED DATA

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2024年第4期44卷 1394-1414页

作者： Minh-Phuong tran The-Quang tran thanh-Nhan NGUYEN Applied Analysis Research Group Faculty of Mathematics and StatisticsTon Duc Thang UniversityHo Chi Minh CityVietnam Nguyen Huu Huan High School Thu Duc CityVietnam Group of Analysis and Applied Mathematics Department of MathematicsHo Chi Minh City University of EducationVietnam

In this paper,the study of gradient regularity for solutions of a class of elliptic problems of p-Laplace type is *** particular,we prove a global result concerning Lorentz-Morrey regularity of the non-homogeneous boundary data problem:-div((s^(2)+|▽u|^(2)p-2/2)▽u)=-div(|f|^(p-2)f)+g inΩ,u=h in■Ω,with the(sub-elliptic)degeneracy condition s∈[0,1]and with mixed data f∈L^(p)(Q;R^(n)),g∈Lp/(p-1)(Ω;R^(n))for p∈(1,n).This problem naturally arises in various applications such as dynamics of non-Newtonian fluid theory,electro-rheology,radiation of heat,plastic moulding and many *** on the idea of level-set inequality on fractional maximal distribution functions,it enables us to carry out a global regularity result of the solution via fractional maximal *** to the significance of M_(α)and its relation with Riesz potential,estimates via fractional maximal functions allow us to bound oscillations not only for solution but also its fractional derivatives of orderα.Our approach therefore has its own interest.

关键词： gradient estimates p-Laplace quasilinear elliptic equation fractional maximal operators Lorentz-Morrey spaces

Assessment of Livelihood Vulnerability to Drought: A Case Study in Dak Nong Province, Vietnam

在线全文

学校读者我要写书评

暂无评论

International Journal of Disaster Risk Science 2019年第4期10卷 604-615页

作者： Nguyen Thi thanh Thao Dao Nguyen Khoi tran thanh xuan Bernard Tychon Universite de Liege 6700 ArlonBelgium Institute for Environmental Science Engineeringand ManagementIndustrial University of Ho Chi Minh CityHo Chi Minh CityVietnam Institute of Research and Development Duy Tan UniversityDa NangVietnam Faculty of Environment University of ScienceVietnam National University Ho Chi Minh CityHo Chi Minh CityVietnam NTT Institute of Hi-Technology Nguyen Tat Thanh UniversityHo Chi Minh CityVietnam

In recent years,droughts have strongly affected the Central Highlands of Vietnam and have resulted in crop damage,yield decline,and serious water *** study investigated the livelihood vulnerability of five communities of farmers who are exposed to droughts in one of the more vulnerable regions of Vietnam—Dak Nong Province.A survey of 250 households was conducted in the five communities to collect data on the region’s sociodemographic profile,livelihood systems,social networks,health status,food and water security,drought conditions,and climate *** were aggregated using a livelihood vulnerability index and the IPCC vulnerability *** survey results indicate that Quang Phu community is the most vulnerable of the study’s communities,followed by Nam N’dir,Dak Nang,Duc Xuyen,and Dak D’ro in descending order of *** availability and livelihood strategies are the most important variables in determining the vulnerability of the five surveyed *** order to reduce vulnerability to droughts,water management practices and livelihood diversification in farming and nonfarming activities are recommended for the study area.

关键词： Agricultural drought Livelihood vulnerability Vietnam Vulnerability indicators

A comparative study on kinetics and dynamics of two dump truck lifting mechanisms using MATLAB simscape

在线全文

学校读者我要写书评

暂无评论

Theoretical & Applied Mechanics Letters 2024年第2期14卷 146-156页

作者： Thong Duc Hong Minh Quang Pham Son Cong tran Lam Quang tran Truong thanh Nguyen Faculty of transportation Engineering Ho Chi Minh City University of Technology(HCMUT)Ho Chi Minh City 700000Vietnam Vietnam National University Ho Chi Minh City(VNU-HCM) Ho Chi Minh City 700000Vietnam Industrial Maintenance Training Center Ho Chi Minh City University of Technology(HCMUT)Ho Chi Minh City 700000Vietnam

In this paper,two lifting mechanism models with opposing placements,which use the same hydraulic hoist model and have the same angle of 50°,have been *** mechanical and hydraulic simulation models are established using MATLAB Simscape to analyze their kinetics and dynamics in the lifting and holding *** simulation findings are compared to the analytical calculation results in the steady state,and both methods show good *** the early lifting stage,Model 1 produces greater force and discharges goods in the container faster than Model ***,Model 2 reaches a higher force and ejects goods from the container cleaner than its counterpart at the end lifting *** established simulation models can consider the effects of dynamic loads due to inertial moments and forces generated during the system *** is crucial in studying,designing,and optimizing the structure of hydraulic-mechanical systems.

关键词： Dump truck Lifting mechanism Hydraulic MATLAB Simscape Kinetic dynamic analysis

Investigation of crack segmentation and fast evaluation of crack propagation, based on deep learning

在线全文

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2024年第4期18卷 516-535页

作者： Than V.tran H.NGUYEN-xuan Xiaoying ZHUANG Institute of Photonics Leibniz University HannoverHannover 30167Germany CIRTech Institute HUTECH UniversityHo Chi Minh City 700000Vietnam College of Civil Engineering Tongji UniversityShanghai 200092China

Identifying crack and predicting crack propagation are critical processes for the risk assessment of engineering *** traditional approaches to crack modeling are faced with issues of high computational costs and excessive computing *** address this issue,we explore the potential of deep learning(DL)to increase the efficiency of crack detection and forecasting crack ***,there is no single algorithm that can fit all data sets well or can apply in all cases since specific tasks *** the paper,we present DL models for identifying cracks,especially on concrete surface images,and for predicting crack ***,SegNet and U-Net networks are used to identify concrete *** gradient descent(SGD)and adaptive moment estimation(Adam)algorithms are applied to minimize loss function during ***,time series algorithms including gated recurrent unit(GRU)and long short-term memory(LSTM)are used to predict crack *** experimental findings indicate that the U-Net is more robust and efficient than the SegNet for identifying crack segmentation and achieves the most outstanding *** evaluation of crack propagation,GRU and LSTM are used as DL models and results show good agreement with the experimental data.

关键词： deep learning crack segmentation crack propagation encoder−decoder recurrent neural network

One-loop contributions for h→ℓℓγ and e−e+→hγ in the U(1)_(B−L) extension of the standard model

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics C 2024年第5期48卷 23-49页

作者： tran Dzung Tri thanh Huy Nguyen Khiem Hong Phan Institute of Fundamental and Applied Sciences Duy Tan UniversityHo Chi Minh City 700000Vietnam Faculty of Natural Sciences Duy Tan UniversityDa Nang City 550000Vietnam VNUHCM-University of Science 227 Nguyen Van CuDistrict 5Ho Chi Minh CityVietnam

We present one-loop contributions for h→ℓℓγ with ℓ=νe,μ,τ,e,μ and e−e+→hγ in the U(1)_(B−L) extension of the standard model. In the phenomenological results, the signal strengths for h→ℓℓγ at the Large Hadron Collider and for e−e+→hγ at future lepton colliders are analyzed in the physical parameter space for both the vector and chiral B−L models. We found that the contributions from the neutral gauge boson Z′ to the signal strengths are rather small. Consequently, the effects will be difficult to probe at future colliders. However, the impacts of charged Higgs and CP-odd Higgs in the chiral B−L model on the signal strengths are significant and can be measured with the help of the initial polarization beams at future lepton colliders.

关键词： Higgs phenomenology one-loop Feynman integrals analytic methods for quantum field theory dimensional regularization future lepton colliders

One-loop contributions for h→?■γ and e-e+→hγ in the U（1）B-L extension of the standard model

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics C 2024年第5期 27-53页

作者： tran Dzung Tri thanh Huy Nguyen Khiem Hong Phan Institute of Fundamental and Applied Sciences Duy Tan University Faculty of Natural Sciences Duy Tan University VNUHCM-University of Science

We present one-loop contributions for h→?■γ with l=ve,μ,τ,e,μ and e-e+→ hγ in the U（1）B-Lextension of the standard *** the phenomenological results,the signal strengths for h→?■γ at the Large Hadron Collider and for e-e+→hγ at future lepton colliders are analyzed in the physical parameter space for both the vector and chiral B-L *** found that the contributions from the neutral gauge boson Z' to the signal strengths are rather ***,the effects will be difficult to probe at future ***,the impacts of charged Higgs and CP-odd Higgs in the chiral B-L model on the signal strengths are significant and can be measured with the help of the initial polarization beams at future lepton colliders.

关键词：

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

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

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

初中级越南汉语学习者状态补语习得偏误研究及建议 ——以胡志明市师范大学中文系为例

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

初中级越南汉语学习者状态补语习得偏误研究及建议 ——以胡志明...

作者：陈氏清草（tran Thi thanh Thao）河北大学

学位级别：硕士

补语是中文语法中的一个重要知识点,也是一个相对难的语法学习点,特别是对于越南学习者,因为在越南语中没有相似的结构,所以对于他们来说补语的难度更大。中文有着丰富而复杂的补语系统,其中,状态补语在汉语中使用频率高、结构复杂、语... 详细信息

补语是中文语法中的一个重要知识点,也是一个相对难的语法学习点,特别是对于越南学习者,因为在越南语中没有相似的结构,所以对于他们来说补语的难度更大。中文有着丰富而复杂的补语系统,其中,状态补语在汉语中使用频率高、结构复杂、语义繁多、语境因素强,被汉语教学界视为汉语教学的重点和难点。笔者是越南留学习者,也曾经经历过汉语学习初中级这段时间,因此特别理解初中级汉语学习者习得过程中的困难与学习过程中的需求。本文主要收集了越南胡志明市师范大学中文系初中级汉语学习者在使用汉语状态补语时产生的偏误,并进行了详细的偏误研究和分析。通过调查与分析,笔者旨在找出更科学有效的汉语状态补语教学方法。本文先对研究背景、研究目的和意义、研究方法等进行说明,对状态补语的语料搜集情况进行概述,本文选择《HSK标准教材2、3》中的状态补语为考察对象,以偏误分析理论、中介语理论和对比分析理论为指导,并采用调查分析、个别访谈等方法进行研究。其次对国际中文教学中的状态补语进行研究综述与相关界定,主要总结了状态补语的本体研究和国际中文教学中的状态补语研究,分析了状态补语研究现状。笔者还对初中级越南学习者的调查问卷和试题进行整理和分析,主要针对胡志明市师范大学中文系的初中级学习者,通过调查问卷与访谈进行状态补语偏误语料的搜集与统计。第四部分对初中级越南学习者学习状态补语的偏误进行了分类,共分为五类。随后,对初中级越南学习者学习汉语状态补语产生偏误的原因进行了分析,分为客观因素和主观因素,并探讨了学习者们回避状态补语学习的现象及其原因。最后是对状态补语的教学思考,针对引起偏误的原因提出具体的教学建议,并设计了部分教学计划,同时提供了《HSK标准教程1、2、3》中状态补语动词相关的参考例句和练习。希望本文研究成果能为越南初中级汉语语法教学提供启示,并能在实际教学中提高教学效果、降低学习难度、减轻教学压力,从而找到最佳的汉语状态补语教学途径。同时,也期望本研究能够为国际中文教学和研究贡献一份力量。

关键词：初中级越南学习者状态补语习得偏误