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Spatiotemporal Trend Analysis of Precipitation Extremes in Ho Chi Minh City, Vietnam During 1980–2017

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International Journal of Disaster Risk Science 2021年第1期12卷 131-146页

作者： nguyen Trong Quan Dao nguyen Khoi nguyen xuan hoan nguyen Ky Phung Thanh Duc Dang Faculty of Environmental and Food Engineering Nguyen Tat Thanh UniversityHo Chi Minh City 700000Vietnam Faculty of Environment University of ScienceHo Chi Minh City 700000Vietnam Vietnam National University Ho Chi Minh City 700000Vietnam Ho Chi Minh City University of Food Industry Ho Chi Minh City 700000Vietnam Institute for Computational Science and Technology Ho Chi Minh City 700000Vietnam Engineering Systems and Design Pillar Singapore University of Technology and DesignTampines 487372Singapore

In this study,the spatiotemporal variability of trends in extreme precipitation events in Ho Chi Minh City during the period 1980–2017 was analyzed based on several core extreme precipitation indices(Rx1 day,Rx5 day,CDD,CWD,R20 mm,R25 mm,R95 p,and SDII).The nonparametric Mann–Kendall and Sen’s slope methods were used to compute the statistical strength,stability,and magnitude of trends in annual rainfall,as well as the extreme precipitation *** found that 64%of the stations had statistically significant upward trends in yearly rainfall,with high magnitudes frequently observed in the northern and southern regions of the *** the extreme precipitation indices,only SDII and R25 mm showed dominantly significant ***,there were increasing trends in the frequency and duration at the southern and central regions of the city during the study ***,El Ni?o-Southern Oscillation and Pacific Decadal Oscillation positively correlated with the duration and negatively correlated with the intensity and frequency of extreme ***,water management plans should be adjusted appropriately to reduce the severe impacts of precipitation extremes on communities and ecosystems.

关键词： Spatiotemporal trend Extreme precipitation Extreme precipitation indices Ho Chi Minh City

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

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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

Advancing Wound Filling Extraction on 3D Faces:An Auto-Segmentation and Wound Face Regeneration Approach

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 2197-2214页

作者： Duong Q.nguyen Thinh D.Le Phuong D.nguyen Nga T.K.Le H.nguyen-xuan Department of Mathematics and Statistics Quy Nhon UniversityQuy Nhon City55100Viet Nam Applied Research Institute for Science and Technology Quy Nhon UniversityQuy Nhon City55100Viet Nam CIRTECH Institute HUTECH UniversityHo Chi Minh City72308Viet Nam

Facial wound segmentation plays a crucial role in preoperative planning and optimizing patient outcomes in various medical *** this paper,we propose an efficient approach for automating 3D facial wound segmentation using a two-stream graph convolutional *** method leverages the Cir3D-FaIR dataset and addresses the challenge of data imbalance through extensive experimentation with different loss *** achieve accurate segmentation,we conducted thorough experiments and selected a high-performing model from the *** selectedmodel demonstrates exceptional segmentation performance for complex 3D facial ***,based on the segmentation model,we propose an improved approach for extracting 3D facial wound fillers and compare it to the results of the previous *** method achieved a remarkable accuracy of 0.9999993% on the test suite,surpassing the performance of the previous *** this result,we use 3D printing technology to illustrate the shape of the wound *** outcomes of this study have significant implications for physicians involved in preoperative planning and intervention *** automating facial wound segmentation and improving the accuracy ofwound-filling extraction,our approach can assist in carefully assessing and optimizing interventions,leading to enhanced patient ***,it contributes to advancing facial reconstruction techniques by utilizing machine learning and 3D bioprinting for printing skin tissue *** source code is available at https://***/SIMOGroup/WoundFilling3D.

关键词： 3D printing technology face reconstruction 3D segmentation 3D printed model

Comparative Chemical Research in Essential Oils from Six Apiaceae Species Growing in the Northern Region of Vietnam

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1677-1687页

作者： nguyen Quang Hung nguyen Thanh Tung nguyen Phuong Hanh Chu Thi Thu Ha nguyen Thi Nhung nguyen Thai An Vu xuan Giang Luong Van Hao Oleh Koshovyi Ain Raal Institute of Ecology and Biological Resources Vietnam Academy of Science and Technology(VAST)Cau GiayHa Noi100000Viet Nam Graduate University of Science and Technology Vietnam Academy of Science and Technology(VAST)Cau GiayHa Noi100000Viet Nam Department of Pharmacognosy Faculty of Pharmacognosy and Traditional MedicineHanoi University of PharmacyHoan KiemHa Noi100000Viet Nam Sa Pa Research Center of Medicinal Materials National Institute of Medicinal MaterialsDien Bien PhuSa PaLao Cai330000Viet Nam Institute of Pharmacy Faculty of MedicineUniversity of TartuTartu50411Estonia

Our study aimed to compare the essential oil(EO)concentration and composition of several Apiaceae species growing in the Northern region of *** yields of EOs from materials ranged from 0.03%(root EO of Angelica acutiloba and aerial parts EO of Heracleum bivittatum)-0.27%(leaf EO of Xyloselinum vietnamense).Gas chromatography-mass spectrometry(GC-MS)allowed the identiﬁcation of 74 components in the EOs of six Apiaceae species,making up 94.4%–100.0%of the *** EO from Angelica acutiloba,(Z)-ligustilide accounted for an extremely large proportion(94.9%).EO of Angelica pubescens was dominated by six character-istic components includingα-pinene(21.5%),β-phellandrene(18.1%),p-cymene(12.2%),3-methylnonane(8.7%),o-cymene(8.1%),and D-sylvestrene(6.2%).The EO from Cryptotaenia japonica was characterized by high amounts ofα-selinene(48.7%),β-selinene(23.7%),and trans-β-farnesene(5.4%).The EOs from leaves and stems of Xyloselinum vietnamense were characterized by high concentrations of sabinene(69.8%and 33.8%),4-terpineol(8.7%and 7.4%)andβ-pinene(4.0%and 6.5%)while EOs from aerial parts and root of Xylo-selinum leonidii comprise four characteristic monoterpenes includingα-pinene(28.2%and 52.8%),β-pinene(7.9%and 10.3%),β-phellandrene(7.6%and 15.3%),and sabinene(3.0%and 4.1%).Additionally,cryptone is also one of the major components in the EO of Xyloselinum leonidii(13.2%in the aerial parts oil and 2.8%in the root oil).In the EOs isolated from the aerial parts and root of Heracleum bivittatum,α-pinene(22.5%and 70.2%)andβ-pinene(43.2%and 20.0%)were the predominant *** appeared in the EO from aerial parts of Heracleum bivittatum with a relatively high concentration(13.5%)while bornyl acetate(5.1%)was also one of the main components in the EO from its aerial parts but was not detected in other Apiaceae species in the present *** databases help identify and control the quality of plant material studied from the family Apiaceae growing in Vietnam.

关键词： Apiaceae essential oil terpenoids gaschromatography-mass spectrometry

Effect of Freeze-Thaw and Urea in Solubility of GPC3-Csub Protein Expressed in Escherichia coli

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Journal of Biosciences and Medicines 2024年第4期12卷 288-297页

作者： xuan-Truc Chu-Dao Kim-Tuyen Huynh-Dam Dang-Thuc Ngo-Luong Quang-Luan Le Thanh-Thao Vo-nguyen Department of Medical Biotechnology Biotechnology Center of Ho Chi Minh City Ho Chi Minh City Vietnam

Glypican-3 is a protein encoded by the Glypican-3 gene located on human X chromosome (Xq26), composed of two subunits, a 40 kDa N-terminal subunit, and a 30 kDa C-terminal subunit. Glypican-3 is a currently potential target molecule for liver cancer treatments because of its over-expression and growth effects on hepatocellular carcinoma (HCC). This study examined the expression and purification of a C-terminal subunit of Glypican-3 protein (GPC3-Csub) due to its application in both diagnosis and therapy for hepatocellular carcinoma. The gene encoding for GPC3-Csub was successfully cloned into plasmid pET28a fused with an affinity tag composed of six consecutive histidine residues (His-tag). Recombinant protein GPC3-Csub was expressed in Escherichia coli BL21 (DE3) in the condition of adding 3% ethanol with IPTG induction. GPC3-Csub was extracted using repeated freeze-thaw cycles with lysozyme, and inclusion bodies were solubilized by 8M Urea, SDS 10% in pH 12. His-tag fused GPC3-Csub proteins allowed it to be purified by affinity chromatography method using the Nickel-nitrilotriacetic acid (Ni-NTA) column. High expression of GPC3-Csub was confirmed by Coomassie staining and western-blot. GPC3-Csub could be isolated with a Ni-NTA column and have a purity of about 90%.

关键词： Glypican-3 Affinity Chromatography Inclusion Body Liver Cancer

New urban map of Eurasia using MODIS and multi-source geospatial data

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Geo-Spatial Information Science 2017年第1期20卷 29-38页

作者： Bayan Alsaaideh Ryutaro Tateishi Dong xuan Phong nguyen Thanh hoan Ahmad Al-Hanbali Bai Xiulian Center for Environmental Remote Sensing(CEReS) Chiba UniversityChibaJapan COPRONA Inc.International Consulting Company Vung TauVietnam Institute of Geography Vietnamese Academy of Science and Technology(VAST)HanoiVietnam Geosphere environmental technology corp. tokyoJapan

Urban areas are of paramount significance to both the individuals and communities at local and regional ***,the rapid growth of urban areas exerts effects on climate,biodiversity,hydrology,and natural ecosystems ***,regular and up-to-date information related to urban extent is necessary to monitor the impacts of urban areas at local,regional,and potentially global *** study presents a new urban map of Eurasia at 500 m resolution using multi-source geospatial data,including Moderate Resolution Imaging Spectroradiometer(MODIS)data of 2013,population density of 2012,the Defense Meteorological Satellite Program’s Operational Linescan System(DMSP-OLS)nighttime lights of 2012,and constructed Impervious Surface Area(ISA)data of *** Eurasian urban map was created using the threshold method for these data,combined with references of fine resolution Landsat and Google Earth *** resultant map was compared with nine global urban maps and was validated using random sampling *** of the accuracy assessment showed high overall accuracy of the new urban map of 94%.This urban map is one product of the 20 land cover classes of the next version of Global Land Cover by National Mapping Organizations.

关键词： Urban area mapping population density MODIS data integration accuracy assessment eurasia

Liouvillian Solutions of Algebraic Ordinary Differential Equations of Order One of Genus Zero

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Journal of Systems Science & Complexity 2023年第2期36卷 884-893页

作者： nguyen Tri Dat NGO Lam xuan Chau Faculty of Basic Science Ho Chi Minh City University of TransportHo Chi Minh CityVietnam Department of Mathematics and Statistics Quy Nhon UniversityQuy Nhon CityVietnam

This paper considers the class of autonomous algebraic ordinary differential equations(AODEs)of order one,and studies their Liouvillian general *** particular,let F(y,w)=0 be a rational algebraic curve over *** authors give necessary and sufficient conditions for the autonomous first-order AODE F(y,y′)=0 to have a Liouvillian solution over ***,the authors show that a Liouvillian solutionαof this equation is either an algebraic function over C(x)or an algebraic function over C(exp(ax)).As a byproduct,these results lead to an algorithm for determining a Liouvillian general solution of an autonomous AODE of order one of genus *** parametrizations of rational algebraic curves play an important role on this method.

关键词： Algebraic ordinary differential equation autonomous differential equation Liouvillian solution rational algebraic curve rational parametrizations

Assessment by microsatellite analysis of genetic diversity and population structure of Enhalus acoroides from the coast of Khanh Hoa Province, Vietnam

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Acta Oceanologica Sinica 2019年第1期38卷 144-150页

作者： xuan-Vy nguyen Papenbrock Jutta Department of Marine Botany Institute of Oceanography Vietnam Academy of Science and Technology Graduate University of Science and Technology Institute of Botany Leibniz University Hannover

Seagrass beds degraded significantly since the last century on both, global and local scale. The seagrass species Enhalus acoroides(Linnaeus f.) Royle is a common species found in almost all marine ecosystems including bays,lagoons and around offshore islands in tropical regions of the West Pacific. It was shown that genetic diversity is an essential indicator of the conditions of ecosystems. In the present study, microsatellite markers were used to assess the genetic diversity and population structure of six distinct seagrass beds along the coast of the Khanh Hoa Province, Vietnam. The results indicate that the genetic diversity of the populations in the open sea is higher than in the lagoon. Seagrass beds occurring in disturbed sites show reduced genetic diversity. The fixing index value(FST) depicts a relatively high genetic structure among populations. Structure analysis clusters the populations into open sea and lagoon populations and cluster analysis and AMOVA indicate a significant difference between the two groups. There are low but non-significant positive correlations between geographic and genetic *** different habitats of the open sea and the lagoon are probably responsible for forming two groups.

关键词： Enhalus acoroides genetic diversity lagoon open sea population structure

Analysis and control of vibration of ropes in a high-rise elevator under earthquake excitation

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Earthquake Engineering and Engineering Vibration 2019年第2期18卷 447-460页

作者： Thuan xuan nguyen Nanako Miura Akira Sone Faculty of Mechanical Engineering Kyoto Institute Technology Matsugasaki

In this research, the vibration of elevator ropes, including the main rope and compensation rope are investigated simultaneously in a high-rise elevator system under earthquake excitation. Moreover, the paper presents a new control method to restrain the sway of both ropes. This study considers varying rope lengths during elevator operation which cause other system parameters such as natural frequency, and damping ratio to be time-variant variables. The dynamics of the ropes are analyzed by solving the governing non-stationary, nonlinear equation numerically. In order to mitigate the vibration of ropes in several motion conditions, particularly upwards movement, downward movement, stopped at the lowest position, and stopped at the highest position, an active equipment is installed at the compensation sheave. The stability of the system using the controller is analyzed at four states: without disturbance and static car, without disturbance and mobile car, including disturbance and static car, and including disturbance and mobile car. The efficiency of the controller used for dampening the vibration of elevator ropes is validated by numerical simulation results.

关键词： elevator ropes high-rise elevator vibration controller stability