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Spatio-temporal changes of underground coal fires during 2008-2016 in Khanh Hoa coal field(North-east of viet Nam) using Landsat time-series data

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Journal of Mountain Science 2018年第12期15卷 2703-2720页

作者： Tuyen Danh vU thanh Tien ngUyen Department of Training Hanoi University of Natural Resources and Environment Faculty of Surveying Mapping and Geographic Information Hanoi University of Natural Resources and Environment

Underground coal fires are one of the most common and serious geohazards in most coal producing countries in the world. Monitoring their spatio-temporal changes plays an important role in controlling and preventing the effects of coal fires, and their environmental impact. In this study, the spatio-temporal changes of underground coal fires in Khanh Hoa coal field(North-East of viet Nam) were analyzed using Landsat time-series data during the 2008-2016 period. Based on land surface temperatures retrieved from Landsat thermal data, underground coal fires related to thermal anomalies were identified using the MEDIAN+1.5×IQR(IQR: Interquartile range) threshold technique. The locations of underground coal fires were validated using a coal fire map produced by the field survey data and cross-validated using the daytime ASTER thermal infrared imagery. Based on the fires extracted from seven Landsat thermal imageries, the spatiotemporal changes of underground coal fire areas were analyzed. The results showed that the thermalanomalous zones have been correlated with known coal fires. Cross-validation of coal fires using ASTER TIR data showed a high consistency of 79.3%. The largest coal fire area of 184.6 hectares was detected in 2010, followed by 2014(181.1 hectares) and 2016(178.5 hectares). The smaller coal fire areas were extracted with areas of 133.6 and 152.5 hectares in 2011 and 2009 respectively. Underground coal fires were mainly detected in the northern and southern part, and tend to spread to north-west of the coal field.

关键词： Underground coal fires Spatio-temporal changes Khanh Hoa coal field (viet Nam) Landsat time-series data

A Neural-network-based Approach to Study the Energy-optimal Hovering Wing Kinematics of a Bionic Hawkmoth Model

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Journal of Bionic Engineering 2019年第5期16卷 904-915页

作者： Anh Tuan nguyen ngoc Doan Tran thanh Trung vu thanh Dong Pham Quoc Tru vu Jae-Hung Han Faculty of Aerospace Engineering Le Quy Don Technical University236 Hoang Quoc VietVietnam Office of International Cooperation Le Quy Don Technical University236 Hoang Quoc VietVietnam Department ofAerospace Engineerings Korea Advanced Institute of Science and Technology Daejeon 34141Republic ofKorea

This paper presents the application of an artificial neural network to develop an approach to determine and study the energy-optimal wing kinematics of a hovering bionic hawkmoth model.A three-layered artificial neural network is used for the rapid prediction of the unsteady aerodynamic force acting on the wings and the required *** this artificial network is integrated into genetic and simplex algorithms,the running time of the optimization process is reduced *** validity of this new approach is confirmed in a comparison with a conventional method using an aerodynamic model based on an extended unsteady vortex-lattice method for a sinu soidal wing kinematics *** studying the obtained results,it is found that actual hawkmoths do not hover under an energy-optimal ***,by tilting the stroke plane and lowering the wing positions,they can compromise and expend some energy to enhance their maneuverability and the stability of their flight.

关键词： optimal hovering wing kinematics artificial neural network insect flight genetic algorithm unsteady vortex-lattice method bionics

Marketing Strategies Evaluation and Selection for Supply Chain Management Under Uncertainty

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Computers, Materials & Continua 2022年第12期73卷 6535-6546页

作者： ngo Quang Trung nguyen van thanh Faculty of Commerce Van Lang UniversityHo Chi Minh City70000Vietnam

Sustainable marketing,often known as green marketing,has grown in popularity over the last two *** is currently putting pressure to encourage firms to become environmentally aware in multiple aspects like human and financial utilization,advertisement,and product *** types of companies are including many environmental campaigns into their own products to take advantage of the *** many scholars have addressed the relevance of green marketing as well as theory development,this study is unique in that it examines both techniques in a fuzzy *** integrated Fuzzy Multicriteria Decision Making Model(MCDM)of the analytical hierarchy process(AHP)and a Portuguese-acronymous MCDM method(TODIM)are used to select the best marketing strategy from five alternatives:(i)Green Design,(ii)Green Positioning,(iii)Green Pricing,(v)Green Packaging,and(iv)Green *** on criteria such as the scale of the green market,price parity,and the commitment of top *** for evaluating green marketing strategies was established in the study as contributions for decisionmakers in this field under unclarified *** research also a useful guideline for ranking alternatives in others industry.

关键词： Green marketing MCDM model sustainable marketing strategy

Minimizing Warpage for Macro-Size Fused Deposition Modeling Parts

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Computers, Materials & Continua 2021年第9期68卷 2913-2923页

作者： thanh Thuong Huynh Tien v.T.nguyen Quoc Manh nguyen Trieu Khoa nguyen Department of Mechanical Engineering Can Tho UniversityCampus IICan ThoVietnam Faculty of Mechanical Technology Industrial University of Ho Chi Minh CityHo Chi Minh70000Vietnam Mechanical Engineering Department National Kaohsiung University of Science and TechnologyKaohsiung80778Taiwan Faculty of Mechanical Engineering Hung Yen University of Technology and EducationHung Yen16000Vietnam

In this study,we investigated warpage and corner lifting minimization for three-dimensional printed parts generated by macro-size fused deposition modeling(FDM).First,the reasons for warpage were theoretically *** approach revealed that the thermal deformation and differential volumetric shrinkage of the extruded molten plastic resulted in warpage of FDM *** addition,low adhesion between the deposited model and the heated or non-heated printing bed may intensify warpage *** a next step,initial small-size and medium-size models were used to identify parameters to manage and minimize warpage in a way that would reduce material consumption and running ***,a macro-size model was built to experimentally investigate and verify the technical solutions to minimize the warpage of FDM *** conclusion,an improved part with reduced warpage was efficiently produced after detailed consideration of thermal effects and adhesion *** exists to widen the application scope of FDM technology in manufacturing for processes like thermoforming that involve mold core fabrication with *** technology,which has applications not only in mechanical engineering but also in related engineering fields,is convenient and could readily be applied to practical manufacturing industries.

关键词： Fused deposition modeling corner lifting volumetric shrinkage thermal deformation acrylonitrile butadiene styrene filament

Novel Deletion in Exon 7 of Betaine Aldehyde Dehydrogenase 2(BADH2)

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Rice science 2023年第2期30卷 104-112,I0020-I0030页

作者： vAN Quoc Giang HUYNH Ky ngUyen Chau thanh Tung ngUyen Loc Hien ngUyen van Manh ngUyen Nhut thanh vO Cong thanh SWEE Keong Yeap College of Agriculture Can Tho UniversityCan Tho 92000Vietnam Department of Sciences and Technology of Long An Province Long An 850000Vietnam China-Association of Southeast Asian Nations College of Marine Sciences Xiamen University MalaysiaSepang 49000SelangorMalaysia

The fragrance of rice is one of the premium characteristics that breeders want to include in rice varieties due to the higher market value. Nucleotide deletions in exons 2(7 bp) and 7(8 bp) of Betaine Aldehyde Dehydrogenase 2(BADH2) are associated with fragrance in rice. In this study, a new 13 bp deletion in exon 7 of the BADH2 gene was discovered in the Nang Thom Cho Dao(NTCD) variety, and the mutation has been closely related to the genetic background of indica subspecies through the Bayesian phylogenetic approach and haplotype network analysis of the 3 000 Rice Genomes Project. In addition, a set of functional markers(EX07-13F, EX07-13RN, and EX07-13RM) identified the 13 bp deletion only within NTCD(no amplified band) compared with both non-aromatic and other aromatic rice varieties(110 bp band). The deletion of 13 bases instead of 8 bases in exon 7 of BADH2 caused a premature stop codon, which down-regulated the expression of the BADH2 transcript while associated with up-regulation of OsP5CS and the high amount of 2-acetyl-1-pyrroline. It is potential to use the deletion in exon 7 of the BADH2 gene as a novel marker for adulteration and breeding of fragrant rice varieties, particularly for NTCD.

关键词： novel deletion BADH2 fragrant rice functional marker

Inactivation effect of pressurized carbon dioxide on bacteriophage Qβ and ΦX174 as a novel disinfectant for water treatment

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Journal of Environmental Sciences 2014年第6期26卷 1301-1306页

作者： Huy thanh vo Tsuyoshi Imai Truc thanh Ho Masahiko Sekine Ariyo Kanno Takaya Higuchi Koichi Yamamoto Hidenori Yamamoto Faculty of Engineering Yamaguchi University 2-16-1 TokiwadaiYamaguchi 755-8611 Japan Faculty of Urban Engineering Central University of ConstructionTuy Hoa Phu Yen 56000 Vietnam

The inactivation effects of pressurized CO2 against bacteriophage Qβ and ФX 174 were investigated under the pressure of 0.3-0.9 MPa, initial concentration of 107-109 PFU/mL, and temperature of 17.8℃-27.2℃. The optimum conditions were found to be 0.7 MPa and an exposure time of 25 min. Under identical treatment conditions, a greater than 3.3-log reduction in bacteriophage Qβ was achieved by CO2, while a nearly 3.0 log reduction was observed for phage ФX174. The viricidal effects of N2O （an inactivation gas with similar characteristics to CO2）, normal acid （HC1）, and CO2 treatment with phosphate buffered saline affirmed the chemical nature of CO2 treatment. The pumping cycle, depressurization rate, and release of intracellular substances caused by CO2 were its viricidal mechanisms. The results indicate that CO2 has the potential for use as a disinfectant without forming disinfection by-products.

关键词： bacteriophage Qβ bacteriophage ФX174 pressurized CO2 viricidal effect microbubbles water disinfection

Development of a Peristaltic Micropump for Bio-Medical Applications Based on Mini LIPCA

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Journal of Bionic Engineering 2008年第2期5卷 135-141页

作者： thanh Tung nguyen My Pham Nam Seo Goo Department of Aerospace Engineering Konkuk University Department of Advanced Technology Fusion Konkuk University

This paper presents the design, fabrication, and experimental characterization of a peristaltic micropump. The micropump is composed of two layers fabricated from Polydimethylsiloxane （PDMS） material. The first layer has a rectangular channel and two valve seals. Three rectangular mini lightweight piezo-composite actuators are integrated in the second layer, and used as actuation parts. Two layers are bonded, and covered by two Polymethyl Methacrylate （PMMA） plates, which help increase the stiffness of the micropump. A maximum flow rate of 900μ*** 1 and a maximum backpressure of 1.8 kPa are recorded when water is used as pump liquid. We measured the power consumption of the micropump. The micropump is found to be a promising candidate for bio-medical application due to its bio-compatibility, portability, bidirectionality, and simple effective design.

关键词： peristaltic micropump LIPCA PDMS bio-medical applications

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

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

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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