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结构与土木工程前沿:英文版 2023年第2期17卷 284-305页

作者： hai-van thi MAI May Huu nguyen Son Hoang TRINH hai-Bang LY Civil Engineering Department University of Transport TechnologyHanoi 100000Vietnam Civil and Environmental Engineering Program Graduate School of Advanced Science and EngineeringHiroshima UniversityHiroshima 739-8527Japan

Fiber-reinforced self-compacting concrete(FRSCC)is a typical construction material,and its compressive strength(CS)is a critical mechanical property that must be adequately *** the machine learning(ML)approach to estimating the CS of FRSCC,the current research gaps include the limitations of samples in databases,the applicability constraints of models owing to limited mixture components,and the possibility of applying recently proposed *** study developed different ML models for predicting the CS of FRSCC to address these *** neural network,random forest,and categorical gradient boosting(CatBoost)models were optimized to derive the best predictive model with the aid of a 10-fold cross-validation technique.A database of 381 samples was created,representing the most significant FRSCC dataset compared with previous studies,and it was used for model *** findings indicated that CatBoost outperformed the other two models with excellent predictive abilities(root mean square error of 2.639 MPa,mean absolute error of 1.669 MPa,and coefficient of determination of 0.986 for the test dataset).Finally,a sensitivity analysis using a partial dependence plot was conducted to obtain a thorough understanding of the effect of each input variable on the predicted CS of *** results showed that the cement content,testing age,and superplasticizer content are the most critical factors affecting the CS.

关键词： compressive strength self-compacting concrete artificial neural network decision tree CatBoost

Electrochemical Immunosensor for Detection of Atrazine Based on Polyaniline/Graphene

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Journal of Materials Science & Technology 2016年第6期32卷 539-544页

作者： nguyen van Chu nguyen hai Binh Cao thi Thanh nguyen van Tu nguyen Le Huy nguyen Tuan Dzung Phan Ngoc Minh Vu thi Thu Tran Dai Lam Institute of Materials Science Vietnam Academy of Science and Technology18 Hoang Quoc VietCau Giay.HanoiViet Nam School of Chemical Engineering.Hanoi University of Science and Technology 1 Dai Co VietHanoiViet Ham Institute for Tropical Technology.Vietnam Academy of Science and Technology 18 Hoang Quoc VietHanoiViet Nam Center for High Technology Development Vietnam Academy of Science and Technology18 Hoang Quoc VietHanoiViet Nam University of Science and Technology of Hanoi.18 Hoang Quoc Viet HanoiViet Ham Graduate University of Science and Technology.Vietnam Academy of Science and Technology 18 Hoang Quoc Viet.HanoiViet Nam

In this study, a novel layer-by-layer polyaniline/graphene （PANi/Gr） structure for electrochemical detec- tion of atrazine was developed. Gr film was synthesized by thermal chemical vapor deposition （CVD） method and transferred onto the PANi-predeposited microelectrode. The properties of PANi/Gr film were thoroughly investigated by high-resolution transmission electron microscopy and Raman techniques. The most attractive feature of this system is a suitable microenvironment, which could provide an amplifi- cation of the conductive signal, thus may contribute to enhancing electron transfer and subsequently improve the sensitivity in electrochemical measurements. With low detection limit （- 43 × 10 -12 g/L）, ac-ceptable stability and good reproducibility, the proposed electrochemical immunosensor could be advantageously extended for multiplexed detection of other agents of environmental pollution.

关键词： Electrochemical immunosensor Polyaniline Graphene Atrazine

A comparative analysis of weight-based machine learning methods for landslide susceptibility mapping in Ha Giang area

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Big Earth Data 2023年第4期7卷 1005-1034页

作者： Thanh Trinh Binh Thanh Luu Trang Ha thi Le Duong Huy nguyen Trong van Tran thi hai van nguyen Khanh Quoc nguyen Lien thi nguyen Faculty of Computer Science Phenikaa UniversityYen NghiaHa DongHanoi 12116Vietnam Phenikaa Research and Technology Institute(PRATI) A&A Green Phoenix Group JSCNo.167 Hoang NganTrung HoaCau GiayHanoi 11313Vietnam Northwestern Geological Division General Department of Geology and Minerals of VietnamHanoiVietnam Youth union office Thuyloi University175 Tay SonDong DaHanoiVietnam Center of Remote Sensing and Geohazards Vietnam Institute of Geosciences and Mineral ResourcesHanoiVietnam

Landslide susceptibility maps (LSMs) are very crucial for planningpolicies in hazardous areas. However, the accuracy and reliability ofLSMs depend on available data and the selection of suitable *** study is conducted to produce LSMs by combinations of machinelearning methods and weighting techniques for Ha Giang province,Vietnam, where has limited data. In study area, we gather 11 landslideconditioning factors and establish a landslide inventory *** the weights of classes (or factors) is very important toprepare data for machine learning methods to generate LSMs. Wefrst use frequency ratio (FR) and analytic hierarchy process (AHP)techniques to generate the weights. Then, random forest (RF), supportvector machine (SVM), logistic regression (LR), and AHP methods arecombined with FR and AHP weights to yield accurate and reliableLSMs. Finally, the performance of these methods is evaluated by fivestatistical metrics, ROC and R-index. The empirical results have shownthat RF is the best method in terms of R-index and the five metrics, *** rate (0.9661), FP rate (0.0), ACC (0.9835), MAE (0.0046), and RMSE(0.0350) for this study area. this study opens the perspective of weightbasedmachine learning methods for landslide susceptibility mapping.

关键词： Landslide logistic regression random forest SvM Vietnam

Optimization Agricultural Supply Chain:A Case Study of Fertilizer Supplier Selection

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Computers, Materials & Continua 2022年第8期72卷 4057-4068页

作者： nguyen van Thanh nguyen thi Kim Lan Syed Tam Husain nguyen Hoang hai nguyen Viet Tinh Faculty of Commerce Van Lang UniversityHo Chi Minh CityVietnam International Education Institute Van Lang UniversityHo Chi Minh CityVietnam

The 21st century is associated with the IndustrialRevolution 4.0 and the organic agriculture trend,making the utilization of high-quality fertilizers,abundant nutritional content,economical,and no affect to environment *** to the new concept,clean agricultural production and organic agricultural products are not allowed to excessively use synthetic chemicals such as chemical fertilizers,and plant protection drugs,but priority is to use manure,organic fertilizers,and natural mineral *** must meet the balanced nutritional requirements of crops,maintain,and improve the fertility of the ground,protect the surrounding ecosystem,and leave harmful effects in agricultural products,products with high quality,safe for users and high economic efficiency for *** achieve the above goal,the selection of a fertilizer supplier is an important decision,supporting the supply chain’s sustainable development,fertilizer supplier selection is a multicriteria decision making model,the decision maker must assess all qualitative and quantitative *** this paper,the author proposed an integer decision making model including Fuzzy Analytic Hierarchy Process(FAHP)and Complex Proportional Assessment of Alternatives(COPRAS)for fertilizer supplier *** weightings of the criteria are calculated by using FAHP,COPRAS is then applied for ranking some potential fertilizer *** efficiency of the proposed models is proved by a case study conducted in a farm located in the south of *** research is the first fertilizer supplier evaluation and se-lection model in Vietnam by interviewing experts and reviewing the ***-search result is to provide a case study on evaluating supplier in agricultural supply chain utilizing the model proposed by the combination of FAHP and COPRAS models.

关键词： Fertilizer industry optimization model fuzzy theory agricultural supply chain

Upconversion luminescence of Gd2O3:Er3+and Gd2O3:Er3+/silica nanophosphors fabricated by EDTA combustion method

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Journal of Rare Earths 2019年第11期37卷 1126-1131页

作者： Le Quoc Minh Tran Kim Anh nguyen Duy Hung Pham thi Minh Chau nguyen thi Quy hai Ho van Tuyen Vu thi Thai Ha Vu Duc Tu Wieslaw Strek Institute of Theoretical and Applied Research Duy Tan UniversityDa Nang 55000Viet Nam Advanced Institute for Science and Technology Hanoi University of Science and Technology1 Dai Co VietHai Ba TrungHanoiViet Nam Institute of Materials Science Vietnam Academy of Science and Technology18 Hoang Quoc Viet RoadCau Giay DistrictHanoiViet Nam Institute of Low Temperature and Structure Research Polish Academy of Science 2 OkolnaWroclawPoland

Gd2O3:Er^3+nanophosphors were fabricated by the combustion method in presence of Na2 ethylene diamine tetra acetic acid(EDTA-Na2)as fuel at not high temperature(≤350℃)within a very short time of 5 *** added concentration of Er^3+ions in Gd2O3 matrix was changed from 0.5 mol%to 5.0 mol%.The X-ray diffraction pattern of samples indicates the monoclinic structure of Gd2O3:Er^3+.The morphology and chemical composition analysis of the Gd2O3:Er^3+samples are characterized by a field emission scanning electron microscope(FESEM)and a Fourier-transform infrared spectrometer(FTIR).The photoluminescence(PL),photo luminescence excitation(PLE)and upconversion(UC)at room temperature of the prepared materials with different concentrations of Er^3+were *** PL of Gd2O3:Er^3+nanomaterials are shown in visible at 545,594,623,648,688 nm under excitation at 275 *** emission bands from transitions of Er^3+from 2P3/2 to 4F9/2 are observed,UC luminescent spectra of the Gd2O3:Er^3+/silica nanocomposites under 976 nm excitation show the bands at 548 and 670 *** influence of excitation power at 980 nm for transitions were measured and *** results indicate that the upconversion process of Gd2O3:Er^3+/silica is two photons absorption *** low temperature dependence of UC luminescent intensities of the main bands of Gd2O3:Er^3+was investigated towards development of a nanotemperature sensor in the range of 10-300 K.

关键词： Upconversion luminescence Gd2O3:Er3+ Gd2O3:Er3+/silica Nanophosphors EDTA combustion Rare earths

Investigation of Polymorphisms in Coding Region of OsHKT1in Relation to Salinity in Rice

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Rice science 2016年第6期23卷 334-338页

作者： pham quynh-hoa tran xuan-an nguyen thi-nha-trang tran thi-thuy-anh hoang hai-yen nguyen thi-hong-van tang thi-hanh do thi-phuc Faculty of Biology VNU University of ScienceHanoi334 Nguyen TraiThanh XuanHanoiVietnam Faculty of Agronomy Vietnam National University of AgricultureNgo Xuan Quang StreetTrau QuyGia LamHanoiVietnam

Rice （Oryza sativa） is sensitive to salinity, but the salt tolerance level differs among cultivars,which might result from natural variations in the genes that are responsible for salt tolerance. High-affinitypotassium transporter （HKTs） has been proven to be involved in salt tolerance in plants. Therefore, wescreened for natural nucleotide polymorphism in the coding sequence of OsHKT1, which encodes the HKTprotein in eight Vietnamese rice cultivars differing in salt tolerance level. In total, seven nucleotidesubstitutions in coding sequence of OsHKT1 were found, including two non-synonymous and five synonymoussubstitutions. Further analysis revealed that these two non-synonymous nucleotide substitutions （G50Tand T1209A） caused changes in amino acids （Gly17Val and Asp403Glu） at signal peptide and the loop ofthe sixth transmembrane domain, respectively. To assess the potential effect of these substitutions on theprotein function, the 3D structure of HKT protein variants was modelled by using PHYRE2 webserver. Theresults showed that no difference was observed when compared those predicted 3D structure of HKTprotein variants with each other. In addition, the codon bias of synonymous substitutions cannot clearlyshow correlation with salt tolerance level. It might be interesting to further investigate the functional roles ofdetected non-synonymous substitutions as it might correlate to salt tolerance in rice.

关键词： polymorphism salt stress OsHKT1 gene rice

Successful containment of a COVID-19 outbreak in Bach Mai Hospital by prompt and decisive responses

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Asian Pacific Journal of Tropical Medicine 2021年第5期14卷 234-235页

作者： van Minh Hoang thi Phuong Thao Tran thi Ngoc Phuong nguyen thi hai Yen nguyen Quang Tuan nguyen Hanoi University of Public Health HanoiVietnam Bach Mai Hospital HanoiVietnam

In low-and middle-income countries,tertiary care hospitals frequently face an extremely heavy workload and shoulder an even heavier burden during the COVID-19 *** Mai Hospital(BMH),one of the leading tertiary hospitals in Vietnam,is on the frontline in the fierce battle against *** letter aims to describe how BMH tackles the COVID-19 outbreak in the hospitallevel battle,which could support policymakers in time-management and well-preparation for this unpredictable pandemic.

关键词： prompt income policy

Land subsidence prediction for a new urban mass rapid transit line in Hanoi

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Underground Space 2020年第2期5卷 93-104页

作者： Pham Huy Giao Vu thi Hue nguyen Dang Han nguyen thi hai Anh nguyen Ngoc Minh Asian Institute of Technology BangkokThailand Institute of Foundation and Underground FECONHanoiViet Nam Sonhai JSC Viet Nam

The rapidly increasing population,urbanization,and industrialization of Hanoi city in the last few decades have necessitated the urgent development of a new underground public transport infrastructure such as the urban mass rapid transit(UMRT)system that is now under ***,concerns on the possible effects of land subsidence on the to-be-constructed and operated UMRT lines must be *** of the difficulties while assessing land subsidence in Hanoi is the insufficient subsidence monitoring ***,a good geotechnical characterization of the subsoil profile and proper numerical analysis can help predict groundwater pumping-induced subsidence *** UMRT line No.2 that was selected for this study is special as it runs across the old quarter downtown,located at the very heart of Hanoi *** this paper,the Hanoi aquifer system,groundwater extraction,and subsidence monitoring network of Hanoi are reviewed *** data from 30 investigation boreholes were analyzed to characterize the subsoil profile underlying a segment of the UMRT line No.2 that consists of both elevated and underground *** soil layers were identified up to a depth of 50 m,including a compressible soft clay layer 10-15 m thick that is supposed to be most vulnerable to subsidence by groundwater *** on the long-term groundwater monitoring data,one-dimensional finite element method(FEM)consolidation analyses were carried out for three drawdown boundary conditions of 5,10,and 15 m and yielded a total subsidence of 0.15,0.35,and 0.5 m,respectively,after 25 years with 1994 as the reference *** results of this study confirmed that land subsidence in particular should be considered in the construction and maintenance of the UMRT lines in Hanoi,in particular for underground sections that are founded on soft to medium clay layers.

关键词： Hanoi aquifer system Groundwater pumping Land subsidence UMRT line Geotechnical characterization

Ecoregional variations of aboveground biomass and stand structure in evergreen broadleaved forests

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Journal of Forestry Research 2020年第5期31卷 1713-1722页

作者： Tran van Do Mamoru Yamamoto Osamu Kozan Vo Dai hai Phung Dinh Trung nguyen Toan Thang Lai Thanh hai Vu Thanh Nam Trieu Thai Hung Hoang van Thang Tran Duc Manh Cao Chi Khiem Vu Tien Lam nguyen Quang Hung Tran Hoang Quy Pham Quang Tuyen Trinh Ngoc Bon nguyen thi Thu Phuong Ninh Viet Khuong nguyen van Tuan Dang thi hai Ha Tran hai Long Dang van Thuyet Dang thinh Trieu nguyen van thinh Tran Anh hai Duong Quang Trung nguyen van Bich Dinh hai Dang Pham Tien Dung nguyen Huy Hoang Le thi Hanh Phan Minh Quang nguyen thi Thuy Huong Hoang Thanh Son nguyen Thanh Son nguyen thi van Anh nguyen thi Hoai Anh Pham Dinh Sam Hoang thi Nhung Hoang van Thanh nguyen Huu thinh Tran Hong van Ho Trung Luong Bui Kieu Hung Research Institute for Sustainable Humanosphere Kyoto UniversityUjiKyotoJapan Silviculture Research Institute Vietnamese Academy of Forest SciencesNorth Tu LiemHanoiVietnam Center for Southeast Asian Studies Kyoto UniversityKyotoJapan Vietnamese Academy of Forest Sciences North Tu LiemHanoiVietnam Vietnam Administration of Forestry No.2 Ngoc HaBa DinhHanoiVietnam

Biotic and abiotic factors control aboveground biomass(AGB)and the structure of forest *** study analyses the variation of AGB and stand structure of evergreen broadleaved forests among six ecoregions of Vietnam.A data set of 1731-ha plots from 52 locations in undisturbed old-growth forests was *** results indicate that basal area and AGB are closely correlated with annual precipitation,but not with annual temperature,evaporation or hours of *** area and AGB are positively correlated with trees>30 cm *** areas surveyed(52.6%)in these old-growth forests had AGB of 100–200 Mg ha^-1;5.2%had AGB of 400–500 Mg ha^-1,and 0.6%had AGB of>800 Mg ha^-*** percent of the areas surveyed had stand densities of 300–600 ***^-1,and 64%had basal areas of 20–40 m^2 ha^-*** is an important factor influencing the AGB of old-growth,evergreen broadleaved forests in *** causing the loss of large-diameter trees(e.g.,>100 cm DBH)affects AGB but may not seriously affect stand density.

关键词： Aboveground biomass Carbon storage Climatic variables Ecoregion Edaphic variables Oldgrowth forest

Hybrid model to optimize object-based land cover classification by meta-heuristic algorithm:an example for supporting urban management in Ha Noi,Viet Nam

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International Journal of Digital Earth 2019年第10期12卷 1118-1132页

作者： Quang-Thanh Bui Manh Pham van nguyen thi Thuy Hang Quoc-Huy nguyen nguyen Xuan Linh Pham Minh hai Tran Anh Tuan Pham van Cu Center for Applied Research in Remote sensing and GIS(CARGIS) VNU University of ScienceHa NoiViet Nam VNU University of Science Ha NoiViet Nam Vietnam Institute of Geodesy and Cartography Ha NoiViet Nam Ministry of Education and Training Ha NoiViet Nam

this study proposed a novel object-based hybrid classification model named GMNN that combines Grasshopper Optimization Algorithm(GOA)and the multiple-class Neural network(MNN)for urban pattern detection in Hanoi,*** bands of SPOT 7 image and derivable NDVI,NDWI were used to generate image segments with associated attributes by PCI Geomatics *** segments were classified into four urban surface types(namely water,impervious surface,vegetation and bare soil)by the proposed ***,three training and validation datasets of different sizes were used to verify the robustness of this *** all tests,the overall accuracies of the classification were approximately 87%,and the Area under Receiver Operating Characteristic curves for each land cover type was ***,the performance of this model was examined by comparing several statistical indicators with common benchmark *** results showed that GMNN out-performed established methods in all comparable *** results suggested that our hybrid model was successfully deployed in the study area and could be used as an alternative classification method for urban land cover *** a broader sense,classification methods will be enriched with the active and fast-growing contribution of metaheuristic algorithms.

关键词： Urban remote sensing object-based classification neural network grasshopper optimization algorithm