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Application of machine learning technique for predicting and evaluating chloride ingress in concrete

Frontiers of Structural and Civil Engineering 2022年第9期16卷 1153-1169页

作者： van Quan TRAN van loi giap Dinh Phien VU Riya Catherine GEORGE Lanh Si HO Department of Civil Engineering University of Transport TechnologyHanoi 100000Vietnam Civil and Environmental Engineering Program Graduate School of Advanced Science and EngineeringHiroshima UniversityHiroshima 739-8527Japan

The degradation of concrete structure in the marine environment is often related to chloride-induced corrosion of reinforcement ***,the chloride concentration in concrete is a vital parameter for estimating the corrosion level of reinforcement *** research aims at predicting the chloride content in concrete using three hybrid models of gradient boosting(GB),artificial neural network(ANN),and random forest(RF)in combination with particle swarm optimization(PSO).The input variables for modeling include exposure condition,water/binder ratio(W/B),cement content,silica fume,time exposure,and depth of *** results indicate that three models performed well with high accuracy of prediction(R2⩾0.90).Among three hybrid models,the model using GB_PSO achieved the highest prediction accuracy(R2=0.9551,RMSE=0.0327,and MAE=0.0181).Based on the results of sensitivity analysis using SHapley Additive exPlanation(SHAP)and partial dependence plots 1D(PDP-1D),it was found that the exposure condition and depth of measurement were the two most vital variables affecting the prediction of chloride *** the number of different exposure conditions is larger than two,the exposure significantly impacted the chloride content of concrete because the chloride ion ingress is affected by both chemical and physical *** study provides an insight into the evaluation and prediction of the chloride content of concrete in the marine environment.

关键词： gradient boosting random forest chloride content concrete sensitivity analysis

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Synthesis and Characterization of LiAlO2for Passive Dosimetry

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World Journal of Nuclear Science and Technology 2022年第1期12卷 21-27页

作者： Nguyen Thi Thu Ha Trinh van giap Bui Duc Ky Institute for Nuclear Science and Technology Vietnam Atomic Energy Institute Hanoi Vietnam

Lithium aluminate (LiAlO2) powder was synthesized by sol-gel with EDTA method. The resultant powders were characterized by X-Ray Diffraction (XRD) and Scanning Electronic Microscopy (SEM) techniques. In addition, several thermoluminescence properties of synthesized LiAlO2 powder were reported. The results from X-ray diffraction (XRD), the powder prepared by sol-gel with EDTA method showed pure γ-phase when it was calcined at >900°C. Scanning electron microscopy (SEM) results show that the size of the lithium aluminate particles depended strongly on calcination temperature. The linearity is observed of synthesized LiAlO2 powder by sol-gel with EDTA with regression coefficient (R2) is 0.9971.

关键词： LiAlO2 XRD SEM TL Response

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Genetic diversity in two threatened species in Vietnam:Taxus chinensis and Taxus wallichiana

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Journal of Forestry Research 2017年第2期28卷 265-272页

作者： Dinh Duy Vu Thi Tuyet Xuan Bui Minh Tam Nguyen Dinh giap Vu Minh Duc Nguyen van Thang Bui Xiaohua Huang Yi Zhang College of Forestry Northwest A&F UniversityYangling 712100ShaanxiPeople's Republic of China Vietnam National Museum of Nature Vietnam Academy of Science and Technology(VAST)18 Hoang Quoc VietCau GiayHanoiVietnam Institute of Ecology and Biological Resource(VAST) 18 Hoang Quoc VietCau GiayHanoiVietnam Institute of Natural Products Chemistry(VAST) 18 Hoang Quoc VietCau GiayHanoiVietnam Institute of Forest Biotechnology Vietnam Forestry UniversityXuan MaiChuong MyHanoiVietnam

Taxus chinensis and T. wallichiana in have been threatened in their distribution areas in recent decades because of their over-exploitation and reduction and destruction of native habitats. Determining the genetic diversity in populations of the two species will provide guidelines for their protection and preservation. Two hundred and fifteen trees from six populations of T. chinensis and150 sampled trees of T. wallichiana were sampled. Six microsatellite primer pairs selected from 16 primer pairs were used to investigate genetic variation at the population and species levels. Five yielded polymorphic alleles, and among the 13 putative alleles amplified, 11 were polymorphic（accounting for 76.33 %）.Shannon＇s information index（I） and percentage of polymorphic bands（PPB）（I = 0.202 and PPB = 67.22 % for T. chinensis; I = 0.217 and PPB = 65.03 % for T. wallichiana）. Both species had low levels of genetic diversity（mean Ho= 0.107, He= 0.121 for T. chinensis; Ho= 0.095, He= 0.109 for T. wallichiana）. Genetic differentiation among populations was higher（FST= 0.189） for T. chinensis and lower（0.156） for ***, indicating limited gene flow（Nm） among populations for T. chinensis（0.68） and T. wallichiana（0.65）.Variation among individuals of T. chinensis was 63.59 and73.12 % for T. wallichiana. Thus, the threatened status of the two conifers is related to a lack of genetic diversity. All populations are isolated in small forest remnants. An ex situ conservation site should be established with a new population for these species that comprises all the genetic groups for the best chance to improve their fitness under environmental stresses.

关键词： Taxus populations alleles polymorphic microsatellite Vietnam primer accounting putative destruction

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Using Isotope Technology for Surface Water Environment Research in Southern Hanoi

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Journal of Environmental Protection 2016年第8期7卷 1113-1118页

作者： Vo Thi Anh Tran Khanh Minh Trinh van giap Ha Lan Anh Nguyen Thanh Cong Nguyen Hong Thinh Vu Hoai Institute for Nuclear Science and Technology Hanoi Vietnam Vinh University Vinh Vietnam

The surface water in the southern of Hanoi capital is researched by identifying δ2H and δ18O stable isotopes together with EC, DO, BOD5, COD, TSS. Surface water samples for studying include the Red river, Nhue river and Kim Nguu river, Thanh Nhan lake, Yen So lake and van Quan lake were collected in the dry season (April) and the rainy season (August) in 2015. The stable isotope analysis results showed that the δ18O values is a range from -42.53‰ to -64.05‰ and, the δ2H values is the range from -5.09‰ to -8.79‰ under global meteoric waterline (in the water vapor region). The δ2H results of the rivers and lakes in the dry season are more negative than the rainy season with a small difference. The δ18O results of lakes in the dry season are more negative than the rainy season, but the δ18O results of river in the dry season are more positive than the rainy season. The results of the EC, BOD, COD, DO, TSS analysis showed that surface water environment has changed clearly in the two seasons and the contamination level in the dry season is usually higher than the rainy season. The lakes and rivers strongly influenced by human activities led to seriously pollution are van Quan lake and Yen So lake, Nhue river and Kim Nguu river.

关键词： Isotope Technology Surface Water Quality Change in Difference Seasons

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Study the Changes in Soil Organic Carbon of Rice-Maize Cropping System in the Top Layer of Alluvisol Soil in Dan Phuong: A Study of C-13 Stable Isotope Composition (δ13C)

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Journal of Environmental Protection 2019年第10期10卷 1361-1372页

作者： Nguyen Thi Hong Thinh Vu Hoai Ha Lan Anh Vo Thi Anh Truong Viet Chau Trinh van giap Tran Minh Tien Isotope Hydrology Laboratory Institute for Nuclear Science and TechnologyHanoiVietnam Soils and Fertilizers Research Institute HanoiVietnam

In this study, the experiments on field were conducted to examine the change in the content of soil organic carbon (SOC), its C-13 stable isotope composition (δ 13C) and some main physical, chemical parameters (soil moisture, pH, soil density, content of humic, fulvic, total N, total P, total K) in alluvial soil of Dan Phuong region—Vietnam at a depth of 0 - 30 cm when we changed the regime from 2 maize -1 rice crop to 2 rice - 1 maize crop per 1 year. In addition to analyzing the main parameters in soil, C content and its δ 13C value in parts of rice and maize (root, stem and leaf) were also analyzed to assess the contribution of plant residues on soil organic carbon content after harvest. The experiment was carried out in 2016-2017 on the field with the traditional farming method of local farmers along with the tropical monsoon weather conditions of the North-Vietnam. The results showed that SOC had positive correlation with total N, total P parameters and negative correlation with δ 13C values of soil samples at two layers (0 - 15 cm and 15 - 30 cm). The average of total dry biomass (stem, stump + roots and leaf parts) per 1 rice and 1 maize crop was 10.64 Mg/ha and 9.09 Mg/ha, respectively. The average of δ 13C value of rice (C3 plant) was -29.78‰ and its value of maize (C4 plant) was -12.61‰. The new plant (rice) contributes to the total soil organic carbon content from 11.31% to 44.14% at the 0 - 15 cm layer and from 6.55% to 11.31% at the 15 - 30 cm layer in one-year experiment period.

关键词： Soil Organic Carbon (SOC) C-13 Stable Isotope Maize and Rice Crop Soil Properties

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Investigation on Infectious Agents of Aborted Pig Fetuses and Its Correlation with PRRSV MLV Vaccine

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Journal of Agricultural Science and Technology(A) 2017年第4期7卷 282-287页

作者： Woo-Taek Oh van-giap Nguyen Hyung-Joon Moon Jee-Hoon Lee Hye-Kwon Kim Seong-Jun Park Hee-Chun Chung Bong-Kyun Park Department of Veterinary Medicine Virology Lab College of Veterinary Medicine and Research Institute for Veterinary ScienceSeoul National University Daehak-ro 1 Gwanak-gu Seou108826 Korea Department of Veterinary Microbiology and Infectious Diseases Faculty of Veterinary Medicine Vietnam National University ofAgriculture Hanoi 50877 Vietnam Viral Infectious Disease Research Unit Green Cross Veterinary Products Yongin 17066 Republic of Korea Viral Infectious Disease Research Center Korea Research Institute of Bioscience and Biotechnology Daejeon 34141 Korea Forensic Medicine Division Daegu Institute National Forensic Service Chilgok 34054 Korea

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Assessment of Radiation Dose Caused by Radioactive Gaseous Effluent Released from Nuclear Power Plant Ninh Thuan 1 under Scenario of Normal Working Conditions

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World Journal of Nuclear Science and Technology 2015年第3期5卷 183-191页

作者： Nguyen Tuan Khai Do Xuan Anh Le Dinh Cuong Duong Duc Thang Vuong Thu Bac Nguyen Thi Thu Ha Nguyen Quang Long Trinh van giap Nguyen Hao Quang Institute for Nuclear Science and Technology (INST) Hanoi Vietnam Vietnam Atomic Energy Institute (VINATOM) Hanoi Vietnam

Based on guides RG 1.109, RG 1.111 published by United States Nuclear Regulatory Commission (USNRC), our research concentrates in assessing radiation doses caused by radioactive substances released from the nuclear power plant (NPP) Ninh Thuan 1 under the scenario of normal operation using software package NRCDose72 provided by the USNRC. The database including the released radioactive nuclides, meteorology, terrain, population and agricultural production activities have been collected and processed to build the input data for the model calculation. The wind rose distribution obtained from the meteorological data in a five-year period from 2009-2013 showed that the radioactive nuclides released to environment spread in two main wind directions which are North East and South West. The X/Q (s/m3) and D/Q (s/m2) qualities which are, respectively, the ratio of activity concentration to release rate and that of deposition density of radioactive nuclides to release rate were calculated within an area of 80 km radius from the NPP site using XOQDOQ. Population doses were calculated using GASPAR. The XOQDOQ and GASPAR are two specific softwares in NRCDose72 package.

关键词： NPP Radioactive Release Radiation Dose Population Dose X/Q and D/Q

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Impacts of the Benefit Sharing Mechanism(BSM)Policy Implementation on Forest Protection and Sustainable Use of Non-timber Products at Bach Ma National Park

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Journal of Agricultural Science and Technology(A) 2017年第B10期7卷 68-77页

作者： Nguyen van loi Nguyen Vu Linh Faculty of Forestry University of Agriculture and ForestryHue UniversityHue 530000Vietnam Bach Ma National Park Thua Thien Hue 530000Vietnam

This study aimed to evaluate the impacts of the benefit sharing mechanism(BSM)pilot policy on sustainable use of non-timber forest products(NTFPs)and natural resources conservation in co-management forest of Bach Ma National *** methods were route and permanent plot survey,household interview,in-depth interview,village meeting,group discussion and workshop at commune *** showed that:(1)the BSM policy had brought favorable conditions for local people in sustainable use and development of the NTFPs,as well as minimised the threats to biodiversity in co-managed forest;(2)the harvest amounts of seven selected NTFPs after two years of the BSM policy implementation were higher than growth rate of every NTFP and the permitted harvest amounts of the benefit sharing plans(BSP);(3)although there was a risk of over-exploitation of the NTFPs,the annual yields in 2013 and 2014 were much lower,but more sustainable than that before the BSM implementation;(4)the forest protection status in the co-management areas was also better than ***,this study has also defined and recommended that in order to continue the BSM,it is necessary to ensure the sustainable exploitation of NTFPs,as well as implement more enforcement activities inside the co-management forest area.

关键词： BSM policy co-management non-timber forest products Bach Ma National Park protection and sustainable use

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Technical Procedure Determination of Thoron Indoor Concentration by LR-115 Type II

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Journal of Environmental Science and Engineering(B) 2016年第3期5卷 109-114页

作者： Nguyen Thi Thu Ha Frinh van giap Le Dinh Cuong Center for Environmental Radiation Monitoring and Impact Assessment Institute for Nuclear Science and Technology (INST)Vietnam Atomic Energy Institute (VINATOM) Hanoi 100000 Vietnam

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A Study on Effects of Blade Pitch on the Hydrodynamic Performances of a Propeller by Using CFD

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Journal of Shipping and Ocean Engineering 2018年第1期8卷 36-42页

作者： NGUYEN Chi Cong LUONG Ngoc loi NGO van He Vietnam Marine University Haiphong 180000 Vietnam Hanoi University of Science and Technology Hanoi 10000 Vietnam

The main objective of this work is to use the CFD (Computational Fluid Dynamics) technique to study the effects of pitch ratio on the controllable pitch propeller"s thrust characteristic. The propeller analyzed is at the following design condition: diameter of 3.65 m, speed of 200 rpm, blade number of 4, average pitch of 2.459 m, pitch ratio at 0.7 of 0.6737. The first stage involves the mesh generation and refinement on domain of the designed propeller. The second stage deals with the identification of initial and boundary conditions of the mesh-equipped module. In the final stage, various results are calculated and analyzed for pitch ratio affecting on the propeller"s thrust characteristic. The achieved results are the basis design and improving efficiency of the controllable pitch propeller.

关键词：推进器 CFD 沥青水动力学表演设计条件液体动力学边界条件

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