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Determination of the Pore Water Velocity Using a Salt Tracer Combined with Self-Potential Measurements

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Journal of Geoscience and Environment Protection 2023年第1期11卷 15-27页

作者： Huong Huynh Thi Thu Son Le Van Hieu Tran Trong Hai Lai viet Quang Nguyen huu Luan Phan Thi Department of Tracer Techniques Center for Applications of Nuclear Technique in Industry Dalat Vietnam

The tracer technique is recommended as an effective tool in surveying abnormal seepage through lakes and dams. By injecting a tracer into a known upstream location and monitoring the appearance of the tracer in the downstream leak point, it is possible to determine the direction and the average water velocity of the preferential flow through the dam. The detailed result achieved depends on the number of samples and the sampling locations to analyze tracer concentration over time in the field. This study proposes to use noninvasive self-potential measurements to determine the location and time the salt tracer moves through the seepage zone. The connection between the potential signal according to the propagation of the NaCl salt tracer and the water velocity was demonstrated through an experiment on a sandbox model. Experimental results express a good agreement between the time to reach the maximum value of the potential variation and the salt concentration variation with the time that water comes to monitoring locations. The result indicates an ability to determine the pore water velocity of the seepage zone based on the recording of potential signals produced by a salt tracer movement. The salt tracer test using NaCl combined with self-potential measurements was then applied to survey a leaking earth dam in the Dong Nai river basin (vietnam).

关键词： Earthen Dams Tracer Technique Leakage Interstitial Velocity

Face Mask Recognition for Covid-19 Prevention

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Computers, Materials & Continua 2022年第11期73卷 3251-3262页

作者： Trong Hieu Luu Phan Nguyen Ky Phuc Zhiqiu Yu Duy Dung Pham huu Trong Cao College of Engineering Can Tho UniversityCan Tho city910900Viet Nam International University-vietnam National University Vietnam National UniversityHoChiMinh City70000Vietnam Department of Industrial Management National Taiwan University of Science and TechnologyTaipei10607Taiwan

In recent years,the COVID-19 pandemic has negatively impacted all aspects of social *** to ease in the infected method,i.e.,through small liquid particles from the mouth or the nose when people cough,sneeze,speak,sing,or breathe,the virus can quickly spread and create severe problems for people’s *** to some research as well as World Health Organization(WHO)recommendation,one of the most economical and effective methods to prevent the spread of the pandemic is to ask people to wear the face mask in the public space.A face mask will help prevent the droplet and aerosol from person to person to reduce the risk of virus *** simple method can reduce up to 95%of the spread of the ***,this solution depends heavily on social consciousness,which is sometimes *** order to improve the effectiveness of wearing face masks in public spaces,this research proposes an approach for detecting and warning a person who does not wear or misuse the face *** approach uses the deep learning technique that relies on GoogleNet,AlexNet,and VGG16 *** results are synthesized by an ensemble method,i.e.,the bagging *** the experimental results,the approach represents a more than 95%accuracy of face mask recognition.

关键词： Face mask detection deep learning AlexNet GoogLeNet VGG16 ensemble method

氮掺杂碳纳米管包覆碳化硅作为不含金属的催化剂(英文)

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催化学报 2014年第6期35卷 906-913页

作者： Cuong Duong-viet Housseinou Ba Yuefeng Liu Lai Truong-Phuoc Jean-Mario Nhut Cuong Pham-huu Institute of Chemistry and Processes for Energy Environment and Health (ICPEES) ECPM UMR 7515 du CNRS-University of Strasbourg 25 rue Becquerel 67087 Strasbourg Cedex 02 France Hanoi University of Mining and Geology Dong Ngac Tu Liem Hanoi Viet Nam

A hierarchical metal-free catalyst consisting of nitrogen-doped carbon nanotubes decorated onto a silicon carbide (N-CNTs/SiC) macroscopic host structure was prepared. The influence of N-CNTs incorporation on the physical properties of the support was evaluated using different characterization techniques. The catalyst was tested as a metal-free catalyst in the selective oxidation of H2S and steam-free dehydrogenation of ethylbenzene. The N-CNTs/SiC catalyst exhibited extremely good desulfurization performance compared to a Fe2O3/SiC catalyst under less conducive reaction conditions such as low temperature, high space velocity, and a low O2-to-H2S molar ratio. For the dehy-drogenation of ethylbenzene, a higher dehydrogenation activity was obtained with the N-CNTs/SiC catalyst compared to a commercial K-Fe/Al2O3 catalyst. The N-CNTs/SiC catalyst also displayed good stability as a function of time on stream for both reactions, which was attributed to the strong anchoring of the nitrogen dopant in the carbon matrix. The extrudate shape of the SiC support allowed the direct macroscopic shaping of the catalyst for use in a conventional fixed-bed reactor without the problems of catalyst handling, transportation, and pressure drop across the catalyst bed that are encountered with nanoscopic carbon-based catalysts.

关键词：催化剂组成碳纳米管碳化硅含金属氮掺杂固定床反应器复合材料氧化铝催化剂

Biomass accumulation of Panax vietnamensis in cell suspension cultures varies with addition of plant growth regulators and organic additives

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Asian Pacific Journal of Tropical Medicine 2017年第9期10卷 907-915页

作者： Tuan Tran Trong Dieu-Hien Truong hoang Chinh Nguyen Dieu-Thai Tran Huyen-Trang Nguyen Thi Giap Do Dang Ho Nguyen huu Plant Cell Technology Department Institute of Tropical BiologyVietnam Academy of Science and Technology9/621 Ha Noi HighwayLinh TrungThu DucHo Chi Minh CityViet Nam Faculty of Applied Sciences Ton Duc Thang University19 Nguyen Huu ThoTan PhongDistrict 7Ho Chi Minh CityViet Nam Genetic Engineering Department Institute of Tropical BiologyVietnam Academy of Science and Technology9/621 Ha Noi HighwayLinh TrungThu DucHo Chi Minh CityViet Nam

Objective: To evaluate the impact of plant growth regulators including kinetin(KN),benzyl adenine and naphthalene acetic acid, yeast extract and casein hydrolyzate on biomass accumulation of vietnamese ginseng Panax vietnamensis(P. vietnamensis) in cell suspension ***: Cell suspension cultures were established from friable calluses derived from leaves and petioles of 3-year-old in-vitro P. vietnamensis plants. The cell suspension cultures were grown in Murashige and Skoog basal media supplemented with various concentrations of KN, benzyl adenine, naphthalene acetic acid, and yeast extract and casein ***: All tested factors generated an increase in the cell biomass of P. vietnamensis in suspension culture, but the impact of each varies depended on the factor type, concentration, and incubation period. Addition of 2.0 mg/L KN resulted in the largest biomass increase after 24 d,(57.0 ± 0.9) and(3.1 ± 0.1) mg/m L fresh and dry weight, respectively,whereas addition of benzyl adenine or naphthalene acetic acid produced optimum levels of Panax cell biomass at 1.0 and 1.5 mg/L, respectively. Addition of the elicitor yeast extract led to a 1.4–2.4 fold increase in biomass of P. vietnamensis, while addition of casein hydrolyzate enhanced biomass accumulation 1.8–2.6 ***: The addition of each factor causes significant changes in biomass accumulation of P. vietnamensis. The largest biomass accumulation is from cultures grown in MS media containing 2.0 mg/L KN for 24 d. The outcome of the present study provides new insights into the optimal suspension culture conditions for studies on the in vitro cell biomass production of P. vietnamensis.

关键词：人参属 vietnamensis 种房间暂停文化种管理者酵母摘录酷蛋白 hydrolyzate 生物资源

Analysis of monomeric and oligomeric organophosphorus flame retardants in fish muscle tissues using liquid chromatographyeelectrospray ionization tandem mass spectrometry:Application to Nile tilapia(Oreochromis niloticus)from an e-waste processing area in northern vietnam

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Emerging Contaminants 2016年第2期2卷 89-97页

作者： Hidenori Matsukami Go Suzuki Nguyen Minh Tue Le huu Tuyen Pham Hung viet Shin Takahashi Shinsuke Tanabe Hidetaka Takigami Center for Material Cycles and Waste Management Research National Institute for Environmental Studies(NIES)16-2 OnogawaTsukuba305-8506Japan Graduate School of Frontier Sciences The University of Tokyo5-1-5 KashiwanohaKashiwa277-8563Japan Center for Marine Environmental Studies(CMES) Ehime University2-5 Bunkyo-choMatsuyama790-8577Japan Centre for Environmental Technology and Sustainable Development(CETASD) VNU Hanoi University of Science334 Nguyen TraiHanoiViet Nam Center of Advanced Technology for the Environment(CATE) Faculty of AgricultureEhime University3-5-7 TarumiMatsuyama790e8566Japan

Using electrospray ionization tandem mass spectrometry combined with liquid chromatography(LC),a novel analytical method was developed to quantify eight monomeric organophosphorus flame retardants(m-PFRs)and three oligomeric organophosphorus flame retardants(o-PFRs)in fish muscle *** optimization and validation experiments indicate that the developed method can determine accurately the concentrations of analytes in fish muscle *** recoveries of analytes in fish muscle samples were in the range of 74-105%.The coefficients of variation of the concentrations of analytes in fish muscle samples were 0.6-8.9%.The concentrations of analytes in procedural blanks were below the limit of quantification(LOQ)***,the developed method was applied to the analysis of m-PFRs and o-PFRs in the muscle samples of tilapias collected from an electronic waste(ewaste)processing area in northern *** concentrations of m-PFRs such as tris(2-chloroethyl)phosphate(TCEP),tris(2-chloroisopropyl)phosphate(TCIPP),and triphenyl phosphate(TPHP)were dominant among the investigated *** respective concentrations of TCEP,TCIPP,and TPHP were up to 160,300,and 230 ng g^-1 lipid weight,respectively,whereas those of o-PFRs were up to 10 ng g^-1 lipid *** results of this study indicate lower accumulation potential of o-PFRs compared with m-PFRs for the first time.

关键词： Monomeric organophosphorus flame retardants Oligomeric organophosphorus flame retardants Liquid chromatographyeelectrospray ionization tandem mass spectrometry Fish muscle tissue e-waste

Improved flood susceptibility mapping using a best first decision tree integrated with ensemble learning techniques

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Geoscience Frontiers 2021年第3期12卷 333-342页

作者： Binh Thai Pham Abolfazl Jaafari Tran Van Phong hoang Phan Hai Yen Tran Thi Tuyen Vu Van Luong huu Duy Nguyen Hiep Van Le Loke Kok Foong University of Transport Technology Ha Noi 100000Viet Nam Research Institute of Forests and Rangelands Agricultural ResearchEducation and Extension Organization(AREEO)TehranIran Institute of Geological Sciences Vietnam Academy of Sciences and Technology84 Chua Lang StreetDong daHa NoiViet Nam Department of Geography School of Social EducationVinh UniversityViet Nam Department of Resource and Environment Management School of Agriculture and ResourcesVinh UniversityViet Nam Faculty of Geography VNU University of Science334 Nguyen TraiHa NoiViet Nam Institute of Research and Development Duy Tan UniversityDa Nang 550000Viet Nam Department for Management of Science and Technology Development Ton Duc Thang UniversityHo Chi Minh CityViet Nam Faculty of Civil Engineering Ton Duc Thang UniversityHo Chi Minh CityViet Nam

Improving the accuracy of flood prediction and mapping is crucial for reducing damage resulting from flood *** this study,we proposed and validated three ensemble models based on the Best First Decision Tree(BFT)and the Bagging(Bagging-BFT),Decorate(Bagging-BFT),and Random Subspace(RSS-BFT)ensemble learning techniques for an improved prediction of flood susceptibility in a spatially-explicit manner.A total number of 126 historical flood events from the Nghe An Province(vietnam)were connected to a set of 10 flood influencing factors(slope,elevation,aspect,curvature,river density,distance from rivers,flow direction,geology,soil,and land use)for generating the training and validation *** models were validated via several performance metrics that demonstrated the capability of all three ensemble models in elucidating the underlying pattern of flood occurrences within the research area and predicting the probability of future flood *** on the Area Under the receiver operating characteristic Curve(AUC),the ensemble Decorate-BFT model that achieved an AUC value of 0.989 was identified as the superior model over the RSS-BFT(AUC=0.982)and Bagging-BFT(AUC=0.967)models.A comparison between the performance of the models and the models previously reported in the literature confirmed that our ensemble models provided a reliable estimate of flood susceptibilities and their resulting susceptibility maps are trustful for flood early warning systems as well as development of mitigation plans.

关键词： Machine learning Ensemble learners Hybrid modeling

Prediction of the Local Scour at the Bridge Square Pier Using a 3D Numerical Model

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Open Journal of Applied Sciences 2014年第2期4卷 34-42页

作者： Nguyen viet Thanh Dang huu Chung Tran Dinh Nghien University of Transport and Communication Hanoi Viet Nam vietnam Academy of Science and Technology Hanoi Viet Nam

In this paper, the problem on local scour around a single square pier was studied by using both the numerical and physical models. The numerical model for the study is FSUM based on a finite-difference method to solve the Reynolds averaged Navier-Stokes equations (RANS) and the equations for suspended sediment concentration and bed morphology. The computed result was verified through data measured in the experimental flume with a sand bed. In general, the typical features of local scour around the pier were successfully simulated by FSUM, such as stream flow, bow flow, down flow, horseshoe vortex. The comparison between the computation and experiment data shows a quite good fitness. Both numerical model and experiment results show that the maximum scour depth occurs at two front edges of the pier. Although the computed result shows a little bigger scour depth in comparison with the measurement in the physical model, it still confirms the reliability of numerical model in some measure.

关键词： Numerical Modeling Experiment Bridge Square Pier Local Scour FSUM Model

Locally weighted learning based hybrid intelligence models for groundwater potential mapping and modeling: A case study at Gia Lai province, vietnam

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Geoscience Frontiers 2021年第5期12卷 54-68页

作者： hoang Phan Hai Yen Binh Thai Pham Tran Van Phong Duong Hai Ha Romulus Costache Hiep Van Le huu Duy Nguyen Mahdis Amiri Nguyen Van Tao Indra Prakash Department of Geography School of Social Sciences EducationVinh University182 Le DuanVinhNghe AnVietnam University of Transport Technology Hanoi 100000Viet Nam Institute of Geological Sciences Vietnam Academy of Science and Technology(VAST)84 Chua LangDong DaHanoiViet Nam Institute for Water and Environment Hanoi 100000Viet Nam Research Institute of the University of Bucharest 90-92 Sos.Panduri5th DistrictBucharestRomania National Institute of Hydrology and Water Management București-Ploiești Road97E1st District013686 BucharestRomania Faculty of Geography VNU University of ScienceVietnam National University334 Nguyen TraiHanoi 100000Viet Nam Department of Watershed&Arid Zone Management Gorgan University of Agricultural Sciences&Natural ResourcesGorgan ***Iran DDG(R)Geological Survey of India Gandhinagar 382010India

The groundwater potential map is an important tool for a sustainable water management and land use planning,particularly for agricultural countries like *** this article,we proposed new machine learning ensemble techniques namely AdaBoost ensemble(ABLWL),Bagging ensemble(BLWL),Multi Boost ensemble(MBLWL),Rotation Forest ensemble(RFLWL)with Locally Weighted Learning(LWL)algorithm as a base classifier to build the groundwater potential map of Gia Lai province in *** this study,eleven conditioning factors(aspect,altitude,curvature,slope,Stream Transport Index(STI),Topographic Wetness Index(TWI),soil,geology,river density,rainfall,land-use)and 134 wells yield data was used to create training(70%)and testing(30%)datasets for the development and validation of the *** statistical indices were used namely Positive Predictive Value(PPV),Negative Predictive Value(NPV),Sensitivity(SST),Specificity(SPF),Accuracy(ACC),Kappa,and Receiver Operating Characteristics(ROC)curve to validate and compare performance of *** show that performance of all the models is good to very good(AUC:0.75 to 0.829)but the ABLWL model with AUC=0.89 is the *** the models applied in this study can support decision-makers to streamline the management of the groundwater and to develop economy not only of specific territories but also in other regions across the world with minor changes of the input parameters.

关键词： Locally weighted learning Hybrid models Groundwater potential GIS vietnam

Drought and conflicts at the local level: Establishing a water sharing mechanism for the summer-autumn rice production in Central vietnam

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International Soil and Water Conservation Research 2019年第4期7卷 362-375页

作者： Chuong Van Huynh Catharien Terwisscha van Scheltinga Ty huu Pham Non Quoc Duong Phuong Thi Tran Linh hoang Khanh Nguyen Tung Gia Pham Ngoc Bich Nguyen Jos Timmerman Hue University Viet Nam Climate Change and Adaptive Land and Water Management Group Wageningen Environmental ResearchNetherlands University of Agriculture and Forestry Hue UniversityViet Nam

In recent years,water for agricultural production gradually became a significant challenge in the context of climate change in *** solutions are required,which consider the use of resources for both human needs and ecology,and that account for the equitable distribution and the livelihood of the farmers now and in the *** particular,the farmers in the province of Quang Nam faring water shortage in the cultivation of paddy in the summer-autumn *** arise regarding the sharing of the water between the farmers,the drinking water company and the hydropower *** the context of climate change,the water shortage is expected to increase in the *** article presents the results of participatory action research (PAR) approach to develop a local level mechanism for water sharing,in which stakeholders actively *** sharing mechanism was developed,envisioning a sustainable solution for inclusive water *** mechanism was successfully implemented in two cases,one at commune level (Tho stream) and one at the district level (Mo stream).The participatory approach proved to be successful in setting up a broadly acceptable mechanism that will need to be further incorporated in the institutional set-up.

关键词： Adaptation Agriculture Climate change Governance Rice production Water sharing