检索结果-南通市图书馆

Frontiers of Structural and Civil Engineering 2024年第3期18卷 461-489页

作者： quoc-Hoa pham Van Ke Tran Phu-Cuong Nguyen Faculty of Engineering and Technology Nguyen Tat Thanh UniversityHo Chi Minh City 700000Vietnam Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoi 100000Vietnam Advanced Structural Engineering Laboratory Department of Structural EngineeringFaculty of Civil EngineeringHo Chi Minh City Open UniversityHo Chi Minh City 700000Vietnam

In this work,a novel refined higher-order shear deformation plate theory is integrated with nonlocal elasticity theory for analyzing the free vibration,bending,and transient behaviors of fluid-infiltrated porous metal foam piezoelectric nanoplates resting on Pasternak elastic foundation with flexoelectric *** analysis(IGA)and the Navier solution are applied to the *** innovation in the present study is that the influence of the in-plane variation of the nonlocal parameter on the free and forced vibration of the piezoelectric nanoplates is investigated for the first *** nonlocal parameter and material characteristics are assumed to be material-dependent and vary gradually over the thickness of *** on Hamilton’s principle,equations of motion are built,then the IGA approach combined with the Navier solution is used to analyze the static and dynamic response of the ***,we investigate the effects of the porosity coefficients,flexoelectric parameters,elastic stiffness,thickness,and variation of the nonlocal parameters on the mechanical behaviors of the rectangular and elliptical piezoelectric nanoplates.

关键词： isogeometric analysis fluid-infiltrated porous piezoelectric nanoplates static and transient analysis flexoelectric effect variable nonlocal parameters

Graphical method based on modified maximum force criterion to indicate forming limit curves of 22MnB5 boron steel sheets at elevated temperatures

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

Journal of Iron and Steel Research(International) 2021年第8期28卷 1009-1018页

作者： Thanh Luyen quoc-tuan pham Thi-Bich Mac Tien-Long Banh Duc-Toan Nguyen Faculty of Mechanical Engineering Hungyen University of Technology and EducationHungyen 160000Vietnam Division of Computational Mathematics and Engineering Institute for Computational ScienceTon Duc Thang UniversityHo Chi Minh City 70000Vietnam Faculty of Civil Engineering Ton Duc Thang UniversityHo Chi Minh City 70000Vietnam School of Mechanical Engineering Hanoi University of Science and TechnologyHanoi City 100000Vietnam

A new approach for predicting forming limit curves(FLCs)at elevated temperatures was proposed *** are often used to predict failure and determine the optimal forming parameters of automotive ***,a graphical method based on a modified maximum force criterion was applied to estimate the FLCs of 22MnB5 boron steel sheets at room temperature using various hardening ***,the predicted FLC data at room temperature were compared with corresponding data obtained from Nakazima's tests to obtain the best *** estimate the FLC at elevated temperatures,tensile tests were conducted at various temperatures to determine the ratios of equivalent fracture strains between the corresponding elevated temperatures and room *** at elevated temperatures could be established based on obtained ***,the predicted FLCs at elevated temperatures did not agree well with the corresponding FLC experimental data of Zhou et al.A new method was proposed herein to improve the prediction of FLCs at elevated *** FLC calculated at room tem-perature was utilized to predict the failure of Nakazima's samples via finite element *** on the simulation results at room temperature,the mathematical relationships between the equivalent ductile fracture strain versus stress triaxiality and strain ratio were established and then combined with ratios between elevated and room temperatures to calculate the FLCs at different *** predicted FLCs at elevated temperatures agree well with the corresponding experimental FLC data.

关键词： Forming limit curve Modified maximum force criterion Graphical method Hardening law Finite element method Boron steel sheet Elevated temperature

Exact solution for thermal vibration of multi-directional functionally graded porous plates submerged in fluid medium

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

Defence Technology（防务技术） 2024年第5期35卷 77-99页

作者： quoc-Hoa pham Van Ke Tran Phu-Cuong Nguyen Faculty of Engineering and Technology Nguyen Tat Thanh UniversityHo Chi Minh CityViet Nam Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoiViet Nam Advanced Structural Engineering Laboratory Department of Structural EngineeringFaculty of Civil EngineeringHo Chi Minh City Open UniversityHo Chi Minh CityViet Nam

An analytical method for analyzing the thermal vibration of multi-directional functionally graded porous rectangular plates in fluid media with novel porosity patterns is developed in this *** properties of MFG porous plates change according to the length,width,and thickness directions for various materials and the porosity distribution which can be widely applied in many fields of engineering and defence ***,new porous rules that depend on spatial coordinates and grading indexes are proposed in the present *** Hamilton's principle and the refined higher-order shear deformation plate theory,the governing equation of motion of an MFG porous rectangular plate in a fluid medium(the fluid-plate system)is *** fluid velocity potential is derived from the boundary conditions of the fluid-plate system and is used to compute the extra *** GalerkinVlasov solution is used to solve and give natural frequencies of MFG porous plates with various boundary conditions in a fluid *** validity and reliability of the suggested method are confirmed by comparing numerical results of the present work with those from available works in the *** effects of different parameters on the thermal vibration response of MFG porous rectangular plates are studied in *** findings demonstrate that the behavior of the structure within a liquid medium differs significantly from that within a vacuum ***,they offer appropriate operational approaches for the structure when employed in various mediums.

关键词： Plate-fluid contact Galerkin Vlasov's method Multi-directional functionally graded plate Novel porosity Thermal vibration Refined higher-order shear deformation theory

EP Aquarii:A New Picture of the Circumstellar Envelope

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第3期24卷 83-105页

作者： pham T.Nhung Do T.Hoai Pierre Darriulat pham tuan-Anh pham N.Diep Nguyen B.Ngoc Tran T.Thai Department of Astrophysics Vietnam National Space CenterVietnam Academy of Science and Technology18Hoang Quoc VietNghia DoCau GiayHa Noivietnam

New analyses of earlier ALMA observations of oxygen-rich AGB star EP Aquarii are presented,which complete a previously published analysis and offer a different interpretation of the morpho-kinematics of the circumstellar *** birth of the equatorial density enhancement(EDE)is shown to occur very close to the star where evidence for rotation has been *** to the star and where outflows have been observed:their interaction with the gas of the nascent EDE is seen to play an important role in the development of the wind and the evolution of its radial velocity from 8 to 10 km s^(-1) on the polar symmetry axis to~2 km s^(-1) at the *** implies complex morpho-kinematics:making reliable interpretations with reasonable confidence is *** particular,it questions an earlier interpretation implying the presence of a white dwarf companion orbiting the star at an angular distance of -0″4 from its *** proposes instead an interpretation in terms of a standard mass ejection associated with a shock wave leaving a void of emission in its *** Doppler velocity wings are seen to consist of two components,the upper velocity end of the global wind,reaching above±12 km s^(-1),and an effective line broadening,confined within 200 mas from the center of the star,reaching above±20 km s^(-1) and interpreted as caused by the pattern of shock waves resulting from the interaction between stellar pulsation and convective cell partition.

关键词： stars AGB and post-AGB-(stars) circumstellar matter-radio lines stars

电针镇痛在甲状腺全切除术中控制术中疼痛和血流动力学的有效性和安全性：一项随机对照试验（英文）

在线全文

学校读者我要写书评

暂无评论

Journal of Traditional Chinese Medical Sciences 2024年第2期11卷 165-171页

作者： Tran,Dong Phuong Nguyen,quoc Dung Nguyen,Ninh Khac pham,Van Hong Senior Specialist Clinic National Hospital of Acupuncture Vietnam National Association of Acupuncture Department of Training and Science National Hospital of Acupuncture

目的：评价电针联合其他药物在甲状腺全切除术中提供镇痛和稳定血流动力学参数的有效性和安全性。方法：该随机对照试验囊括了100例患者，这些患者于2022年10月至2023年10月在越南国立针灸医院接受了甲状腺全切除术。患者被随机分为了... 详细信息

目的：评价电针联合其他药物在甲状腺全切除术中提供镇痛和稳定血流动力学参数的有效性和安全性。方法：该随机对照试验囊括了100例患者，这些患者于2022年10月至2023年10月在越南国立针灸医院接受了甲状腺全切除术。患者被随机分为了两组。电针镇痛组（EA）对合谷穴（LI 4）、内关穴（PC 6）、水突穴（ST 10）、缺盆穴（ST 12）、翳风穴（SJ 17）5个穴位进行了电针刺激，对照组患者进行了双侧浅表颈丛神经阻滞。主要结局包括两组患者的镇痛水平和围手术期生命体征。此外，测定了EA组患者电针前后的疼痛阈值和血清β-内啡肽水平。结果：EA组和对照组分别有86%和76%的患者达到完全镇痛（A级），两组间无显著差异（P=1.00）。EA组患者接受EA后平均疼痛阈值翻倍（648.7(77.4) g/s vs. 305.3 (45.3) g/s, P <0.001），平均血清β-内啡肽水平增加了约13.5pg/m L(P <0.001)。所有患者在整个手术过程中的血流动力学维持稳定。结论：EA联合其他药物刺激了5个穴位，LI 4、PC 6、ST 10、ST 12和SJ 17，在甲状腺全切除术中耐受良好，有效地维持了适当的镇痛水平和血流动力学稳定性。

关键词：电针针灸镇痛格雷夫斯病甲状腺切除术甲状腺手术 β-内啡肽

Dynamic analysis of bio-inspired helicoid laminated composite plates resting on Pasternak foundation excited by explosive loading

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2023年第12期30卷 126-140页

作者： Ngoc-Tu Do quoc-Hoa pham Faculty of Mechanical Engineering Hanoi University of IndustryHanoiViet Nam Faculty of Engineering and Technology Nguyen Tat Thanh UniversityHo Chi Minh CityViet Nam

This paper uses isogeometric analysis(IGA)based on higher-order shear deformation theory(HSDT)to study the dynamic response of bio-inspired helicoid laminated composite(B-iHLC)plates resting on Pasternak foundation(PF)excited by explosive *** takes advantage of non-uniform rational Bspline(NURBS)basic functions to exactly represent the structure geometry models and the attainment of higher-order approximation *** method also ensures a C1 continuous function in the analysis of transverse shear deformation via ***,IGA eliminates the requirement for correction factors and delivers accurate *** foundation with two stiffness parameters:springer stiffness(k_(1))and shear stiffness(k_(2)).The derivation of the governing equations is based on Hamilton's *** proposed method is validated through numerical examples.A comprehensive analysis of the impact of geometrical parameters,material properties,boundary conditions(BCs),and foundation stiffness on dynamic response of B-i HLC plates is carried out.

关键词： Isogeometric analysis Pasternak foundation Dynamic response Laminated composite

Nonlinear dynamic analysis of functionally graded carbon nanotube-reinforced composite plates using MISQ20 element

在线全文

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2023年第7期17卷 1072-1085页

作者： quoc-Hoa pham Trung Thanh TRAN Phu-Cuong NGUYEN Advanced Structural Engineering Laboratory Department of Structural EngineeringFaculty of Civil EngineeringHo Chi Minh City Open UniversityHo Chi Minh City 700000Vietnam Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoi 100000Vietnam

The main objective of this study is to further extend the mixed integration smoothed quadrilateral element with 20 unknowns of displacement(MISQ20)to investigate the nonlinear dynamic responses of functionally graded carbon nanotube-reinforced composite(FG-CNTRC)plates with four types of carbon nanotube *** smooth finite element method is used to enhance the accuracy of the Q4 element and avoid shear locking without using any shear correction *** method yields accurate results even if the element exhibits a concave quadrilateral shape and reduces the error when the element meshing is ***,the element stiffness matrix is established by integrating the boundary of the smoothing *** motion equation of the FG-CNTRC plates is solved by adapting the Newmark method combined with the Newton–Raphson ***,the calculation program is coded in the MATLAB software and verified by comparing it with other published ***,the effects of the input parameters on the nonlinear vibration of the plates are investigated.

关键词： carbon nanotube MISQ20 FG-CNTRC plate nonlinear vibration nonlinear dynamic analysis SFEM

Vibration characteristics of sandwich plates with an auxetic honeycomb core and laminated three-phase skin layers under blast load

在线全文

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2023年第6期24卷 148-163页

作者： quoc-Hoa pham Van Ke Tran Trung Thanh Tran Faculty of Engineering and Technology Nguyen Tat Thanh UniversityHo Chi Minh CityViet Nam Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoiViet Nam

In this article,vibration characteristics of sandwich plates with an auxetic honeycomb core and laminated three-phase skin layers subjected to blast load are ***-order ES-MITC3 element based on higher-order shear deformation theory(HSDT)to achieve the governing *** sandwich plates with the ultra-light feature of the auxetic honeycomb core layer(negative Poisson’s ratio)and reinforced by two laminated three-phase skin *** obtained results in our work are compared with other previously published to confirm accuracy and *** addition,the effects of parameters such as geometrical and material parameters on the vibration characteristics of sandwich plates with an auxetic honeycomb core and laminated three-phase skin layers are fully investigated.

关键词： Laminated three-phase Sandwich plate Auxetic honeycomb ES-MITC3 element High-order shear deformation theory

Free vibration analysis of functionally graded porous curved nanobeams on elastic foundation in hygro-thermo-magnetic environment

在线全文

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2023年第4期17卷 584-605页

作者： quoc-Hoa pham Parviz MALEKZADEH Van Ke TRAN Trung NGUYEN-THOI Faculty of Engineering and Technology Nguyen Tat Thanh UniversityHo Chi Minh City 700000Vietnam Department of Mechanical Engineering Persian Gulf UniversityBushehr ***Iran Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoi 100000Vietnam Laboratory for Applied and Industrial Mathematics Institute for Computational Science and Artificial IntelligenceVan Lang UniversityHo Chi Minh City 700000Vietnam Faculty of Mechanical-Electrical and Computer Engineering School of TechnologyVan Lang UniversityHo Chi Minh City 700000Vietnam Bualuang ASEAN Chair Professor Thammasat School of EngineeringThammasat UniversityPathumtani 12120Thailand

Herein,a two-node beam element enriched based on the Lagrange and Hermite interpolation function is proposed to solve the governing equation of a functionally graded porous(FGP)curved nanobeam on an elastic foundation in a hygro–thermo–magnetic *** material properties of curved nanobeams change continuously along the thickness via a power-law distribution,and the porosity distributions are described by an uneven porosity *** effects of magnetic fields,temperature,and moisture on the curved nanobeam are assumed to result in axial loads and not affect the mechanical properties of the *** equilibrium equations of the curved nanobeam are derived using Hamilton’s principle based on various beam theories,including the classical theory,first-order shear deformation theory,and higher-order shear deformation theory,and the nonlocal elasticity *** accuracy of the proposed method is verified by comparing the results obtained with those of previous reliable ***,the effects of different parameters on the free vibration behavior of the FGP curved nanobeams are investigated comprehensively.

关键词： functionally graded porous material curved nanobeam hygro-thermo-magnetic enriched finite element method

A novel finite element formulation for static bending analysis of functionally graded porous sandwich plates

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

Frontiers of Structural and Civil Engineering 2022年第12期16卷 1599-1620页

作者： Van Chinh NGUYEN Trung Thanh TRAN Trung NGUYEN-THOI quoc-Hoa pham Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoiVietnam Laboratory for Applied and Industrial Mathematics Institute for Computational Science and Artificial IntelligenceVan Lang UniversityHo Chi Minh CityVietnam Faculty of Mechanical-Electrical and Computer Engineering Van Lang UniversityHo Chi Minh CityVietnam Faculty of Engineering and Technology Nguyen Tat Thanh UniversityHo Chi Minh CityVietnam

This article aims to propose a finite element formulation based on Quasi-3D theory for the static bending analysis of functionally graded porous(FGP)sandwich *** FGP sandwich plates consist of three layers including the bottom skin of homogeneous metal,the top skin of fully ceramic and the FGP core layer with uneven porosity distribution.A quadrilateral(Q4)element with nine degrees of freedom(DOFs)per node is derived and employed in analyzing the static bending response of the plate under uniform and/or sinusoidally distributed *** accuracy of the present finite element formulation is verified by comparing the obtained numerical results with the published results in the ***,some numerical examples are performed to examine the effects of the parameters including power-law index k and porosity coefficient on the static bending response of rectangular FGP sandwich *** addition,a problem with a complicated L-shape model is conducted to illustrate the superiority of the proposed finite element method.

关键词： sandwich plates functionally graded porous static bending Quasi-3D theory Q4 element