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Asian Herpetological Research 2015年第1期6卷 66-72页

作者： dzung trung le Anh Van PHAM Son Hung Lan NGUYEN Thomas ZIEGleR Truong Quang NGUYEN Faculty of Biology Hanoi National University of Education Faculty of Biology and Chemistry Tay Bac University AG Zoologischer Garten Kln Institute of Ecology and Biological Resources Vietnam Academy of Science and Technology

Two amphibian species,Megophrys daweimontisandAmolops vitreus,are recorded for the ifrst time from Vietnam, on the basis of a new amphibian collection from Dien Bien and Son La provinces. In addition, acoustic analysis ofA. vitreus is also provided based on the advertisement calls recorded in Muong Nhe Nature Reserve of Dien Bien Province, Vietnam.

关键词： Amolops vitreus Megophrys daweimontis new records advertisement call Dien Bien Province Son La Province

Dynamic response of honeycomb-FGS shells subjected to the dynamic loading using non-polynomial higher-order IGA

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Defence Technology（防务技术） 2024年第7期37卷 149-161页

作者： Pham Binh le trung-Thanh Tran Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoiViet Nam

The main goal of this study is to use higher-order isogeometric analysis(IGA)to study the dynamic response of sandwich shells with an auxetic honeycomb core and two different functionally graded materials(FGM)skin layers(namely honeycomb-FGS shells)subjected to dynamic ***'s non-polynomial higher-order shear deformation theory(HSDT)is used due to its simplicity and *** governing equation is derived from Hamilton's *** verifying the present approach,the effect of input parameters on the dynamic response of honeycomb-FGS shells is carried out in detail.

关键词： IGA Elastic foundation Dynamic response FGM Auxetic honeycomb Shell

Optimal turning method of composting regarding hygienic safety

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Journal of Environmental Sciences 2005年第2期17卷 194-199页

作者： Masafumi Tateda le Duc trung Michihiko Ike Masanori Fujita Department of Environmental Systems Engineering College of TechnologyToyama Prefectural University5180 KurokawaKosugiImizuToyama 939-0398Japan Department of Environmental Engineering Graduate School of EngineeringOsaka University2-1 YamadaokaSuitaOsaka 565-0871Japan

The new turning method was proposed and verified its effectiveness to pathogens by laboratory scale *** the results obtained from the previous studies,it could be said that turning of a composting pile was essential in terms of hygienic aspects but the number of turning should be *** of inactivation was estimated for each composting *** this estimation,turning by layers,which is different from conventional turning that mixes compost pile entirely,was proposed and investigated its performance by *** operations with static pile method,complete mix(conventional)turning method,and proposed turning(layer turning)method were done and their effectiveness on inactivation of indicator microorganism was evaluated and *** results,the conventional turning method was not a proper method in terms of pathogen inactivation,whereas,the proposed turning method showed an excellent performance and should be employed in a composting operation.

关键词： composting turning inactivation hygienic safety

Transparent, stretchable, and rapid-response humidity sensor for body-attachable wearable electronics

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Nano Research 2017年第6期10卷 2021-2033页

作者： Tran Quang trung le Thai Duy Subramanian Ramasundaram Nae-Eung lee School of Advanced Materials Science & Engineering Sungkyunkwan University (SKKU) Suwon Kyunggi-do 16419 Republic of Korea Center for Water Resource Cycle Research Korea Institute of Science and Technology Hwarang-ro 14 gil Seongbuk-gu Seoul 02793 Republic of Korea SKKU Advanced Institute of Nanotechnology (SAINT) SKKU Suwon Kyunggi-do 16419 Republic of Korea Samsung Advanced Institute for Health Sciences & Technology (SAIHST) SKKU Suwon Kyunggi-do 16419 Republic of Korea

Stretchable and conformal humidity sensors that can be attached to the human body for continuously monitoring the humidity of the environment around the human body or the moisture level of the human skin can play an important role in electronic skin and personal healthcare applications. However, most stretchable humidity sensors are based on the geometric engineering of non-stretchable components and only a few detailed studies are available on stretchable humidity sensors under applied mechanical deformations. In this paper, we propose a transparent, stretchable humidity sensor with a simple fabrication process, having intrinsically stretchable components that provide high stretchability, sensitivity, and stability along with fast response and relaxation time. Composed of reduced graphene oxide-polyurethane composites and an elastomeric conductive electrode, this device exhibits impressive response and relaxation time as fast as 3.5 and 7 s, respectively. The responsivity and the response and relaxation time of the device in the presence of humidity remain almost unchanged under stretching up to a strain of 60% and after 10,000 stretching cycles at a 40% strain. Further, these stretchable humidity sensors can be easily and conformally attached to a finger for monitoring the humidity levels of the environment around the human body, wet objects, or human skin.

关键词： transparent stretchablehumidity sensor reduced graphene oxide wearable electronics body-attachable intrinsically stretchable components

Two-Channel Highly Sensitive Sensors Based on 4 × 4 Multimode Interference Couplers

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Photonic Sensors 2017年第4期7卷 357-364页

作者： trung-Thanh le International School (VNU-IS) Vietnam National University (VNU) Hanoi Vietnam

We propose a new kind of microring resonators （MRR） based on 4 × 4 multimode interference （MMI） couplers for multichannel and highly sensitive chemical and biological sensors. The proposed sensor structure has advantages of compactness and high sensitivity compared with the reported sensing structures. By using the transfer matrix method （TMM） and numerical simulations, the designs of the sensor based on silicon waveguides are optimized and demonstrated in detail. We apply our structure to detect glucose and ethanol concentrations simultaneously. A high sensitivity of 9000 nm/RIU, detection limit of 2 × 10^-4 for glucose sensing and sensitivity of 6000 nm/RIU, detection limit of 1.3 × 10^-5 for ethanol sensing are achieved.

关键词： Biological sensors chemical sensors optical microring resonators high sensitivity multimodeinterference transfer matrix method beam propagation method (BPM) multichannel sensor

Discrete-time sliding mode control with power rate exponential reaching law of a pneumatic artificial muscle system

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Control Theory and Technology 2022年第4期20卷 514-524页

作者： Quy-Thinh Dao trung-Kien le Tri Van-Anh Nguyen Manh-Linh Nguyen School of Electrical and Electronic Engineering Hanoi University of Science and TechnologyDai Co VietHanoi 11615Vietnam

This paper develops a discrete-time sliding mode controller with a power rate exponential reaching law approach to enhance the performance of a pneumatic artificial muscle system in both reaching time and chattering *** proposed method dynamically adapts to the variation of the switching function,which is based on an exponential term and a power rate term of the sliding ***,the controlled system can achieve high tracking performance while still obtain chattering-free ***,the effectiveness of the proposed method is validated through multiple experimental tests,focused on a dual pneumatic artificial muscle ***,experimental results show the effectiveness of the proposed approach in this paper.

关键词： Pneumatic artificial muscle Discrete-time sliding mode control Exponential reaching law Chattering

Suzuki Reaction of Aryl Bromides Using a Phosphine-Free Magnetic Nanoparticle-Supported Palladium Catalyst

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催化学报 2011年第11期32卷 1667-1676页

作者： Nghia T. BUI trung B. DANG Ha V. le Nam T. S. PHAN Department of Chemical Engineering HCMC University of Technology VNU-HCM 268 Ly Thuong Kiet Distriet 10 Ho Chi Minh City Viet Nam

A palladium catalyst immobilized on superparaganetic nanoparticles was prepared with a palladium loading of 0.30 mmol/g. The catalyst was characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometry, thermogravimetric analysis, Fourier transform infrared, atomic absorption spectrophotometry, and nitrogen adsorption. The immobilized palladium catalyst was an efficient catalyst without added phosphine ligands for the Suzuki cross-coupling reaction of several aryl bromides with phenylboronic acid. The recovery of catalyst was simply by magnetic decantation in the presence of a magnet. The immobilized palladium catalyst can be reused many times without significant degradation in catalytic activity. No leaching of active palladium species into the reaction solution was detected.

关键词： superparamagnetic nanoparticle Suzuki reaction palladium aryl bromide

Static and free vibration analyses of functionally graded porous variable-thickness plates using an edge-based smoothed finite element method

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Defence Technology（防务技术） 2021年第3期17卷 971-986页

作者： trung Thanh Tran Quoc-Hoa Pham trung Nguyen-Thoi Department of Mechanics 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

The main purpose of this paper is to present numerical results of static bending and free vibration of functionally graded porous(FGP) variable-thickness plates by using an edge-based smoothed finite element method(ES-FEM) associate with the mixed interpolation of tensorial components technique for the three-node triangular element(MITC3), so-called ES-MITC3. This ES-MITC3 element is performed to eliminate the shear locking problem and to enhance the accuracy of the existing MITC3 element. In the ES-MITC3 element, the stiffness matrices are obtained by using the strain smoothing technique over the smoothing domains formed by two adjacent MITC3 triangular elements sharing an edge. Materials of the plate are FGP with a power-law index(k) and maximum porosity distributions(U) in the forms of cosine functions. The influences of some geometric parameters, material properties on static bending, and natural frequency of the FGP variable-thickness plates are examined in detail.

关键词： Functionally graded porous(FGP)plates Edge-based smoothed finite element method(ES-FEM) Mixed interpolation of tensorial components(MITC) Static bending Free vibration

Flow Visualization of Rhinoceros Beetle （Trypoxylus dichotomus） in Free Flight

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Journal of Bionic Engineering 2012年第3期9卷 304-314页

作者： Tien Van Truong Tuyen Quang le Hieu trung Tran Hoon Cheol Parka Kwang Joon Yoon Doyoung Byun . Department of Aerospace Information Engineering Konkuk University Seoul 143-70 l Republic of Korea 2.Costal Engineering and Ocean Energy Research Department Korea Ocean Research and Development Institute 454 Haeanro Sangrok-gu Ansan 426-744 Republic of Korea Department of Advanced Technology Fusion Konkuk University Seoul 143-701 Republic of Korea Department of Mechanical Engineering Sungkyunkwan University Suwon 440-746 Republic of Korea

Aerodynamic characteristics of the beetle, Trypoxylus dichotomus, which has a pair of elytra （forewings） and flexible hind wings, are investigated. Visualization experiments were conducted for various flight conditions of a beetle, Trypoxylus di- chotomus： free, tethered, hovering, forward and climbing flights. leading edge, trailing edge and tip vortices on both wings were observed clearly. The leading edge vortex was stable and remained on the top surface of the elytron for a wide interval during the downstroke of free forward flight. Hence, the elytron may have a considerable role in lift force generation of the beetle. In addition, we reveal a suction phenomenon between the gaps of the hind wing and the elytron in upstroke that may improve the positive lift force on the hind wing. We also found the reverse clap-fling mechanism of the T. dichotomus beetle in hovering flight. The hind wings touch together at the beginning of the upstroke. The vortex generation, shedding and interaction give a better understanding of the detailed aerodynamic mechanism of beetle flight.

关键词： beetle smoke wire visualization free flight hovering flight wing interaction elytron effect

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

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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