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Frontiers of Structural and Civil Engineering 2022年第2期16卷 224-238页

作者： Hai-Bang LY huong-lan thi vu lanh Si HO Binh Thai PHAM Department of Civil Engineering University of Transport TechnologyHanoi100000Vietnam Civil and Environmental Engineering Program Hiroshima UniversityHiroshima739-8527Japan Department of Science Technology and International CooperationUniversity of Transport TechnologyHanoi100000Vietnam

The consolidation coefficient of soil(C_(v))is a crucial parameter used for the design of structures leaned on soft *** general,the C_(v) is determined experimentally in the ***,the experimental tests are time-consuming as well as ***,researchers tried several ways to determine C_(v) via other simple soil *** this study,we developed a hybrid model of Random Forest coupling with a Relief algorithm(RF-RL)to predict the C_(v) of *** conduct this study,a database of soil parameters collected from a case study region in Vietnam was used for *** performance of the proposed models was assessed via statistical indicators,namely Coefficient of determination(R^(2)),Root Mean Squared Error(RMSE),and Mean Absolute Error(MAE).The proposal models were constructed with four sets of soil variables,including 6,7,8,and 13 *** results revealed that all models performed well with a high performance(R^(2)>0.980).Although the RF-RL model with 13 variables has the highest prediction accuracy(R^(2)=0.9869),the difference compared with other models was negligible(i.e.,R^(2)=0.9824,0.9850,0.9825 for the cases with 6,7,8 inputs,respectively).Thus,it can be concluded that the hybrid model of RF-RL can be employed to predict C_(v) based on the basic soil parameters.

关键词： soil consolidation coefficient machine learning random forest Relief

Fabrication and characterization of YVO_4:Eu^(3+) nanomaterials by the microwave technique

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Journal of Rare Earths 2011年第12期29卷 1137-1141页

作者： Tran Thu huong vu Duc Tu Tran Kim Anh Le thi Vinh Le Quoc Minh Institute of Materials Science Vietnamese Academy of Science and Technology University of Engineering and Technology National University Hanoi Departments of Chemistry Hanoi University of Mining and Geology

Fabrication and characterization of YVO4：Eu^3＋ nanophosphors prepared by microwave （MW） irradiation assisted soft template synthesis were reported. The effects of synthesis conditions such as different powers of MW irradiation, pH values and concentration of reac- tion materials on properties of nanophosphor were also investigated to obtain the controllable size, morphology and high luminescence efficiency. Morphology, crystalline structure, and optical properties were characterized by field emission scanning electron microscopy （FE-SEM）, X-ray diffraction （XRD） and fluorescence spectroscopy, respectively. The results showed that YVOa：Eu^3＋ nanophosphors were obtained by using diethyleneglycol （DEG） as soft template, with pH values in the range of 4 to 12, upon microwave irradiation from 300 to 900 W, at temperature of 80 ℃. The high fluorescent YVOa：Eu^3＋ nanocrystals obtained with size from 15 nm down to 8 nm are more effective to develop an ultrahigh sensitive fluorescent label for biomolecule, cell and tissue.

关键词： microwave synthesis method DEG soft template YVO4:Eu^3+ nanophosphor luminescence rare earths

An Analytical Approach for Nonlinear Buckling Analysis of Torsionally Loaded Sandwich Carbon Nanotube Reinforced Cylindrical Shells with Auxetic Core

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Advances in Applied Mathematics and Mechanics 2023年第2期15卷 468-484页

作者： Dang Thuy Dong Nguyen thi Phuong vu Hoai Nam Le Ngoc Ly Nguyen Van Tien vu Minh Duc Tran Quang Minh vu Tho Hung Nguyen thi huong Giang Faculty of Civil Engineering University of Transport TechnologyHanoi 100000Vietnam Graduate School of Advanced Science and Engineering Hiroshima University1-4-1 KagamiyamaHigashi-HiroshimaHiroshima 739-8527Japan Faculty of Fundamental Science for Engineering University of Transport TechnologyHanoi 100000Vietnam

The main aim of this paper is to present an analytical approach on the postbuckling for torsionally loaded sandwich carbon nanotube(CNT)reinforced cylindrical shells with the auxetic *** considered shells consist of three layers,external and internal CNT reinforced layers,and the auxetic lattice core made by isotropic *** homogenization model for honeycomb auxetic lattice core is utilized,and the equilibrium equations are formulated based on the nonlinear Donnell’s thin shell theory with von Karman geometrical *** three terms of deflection are considered,the Airy’s stress function and Galerkin’s method are utilized,the explicit expression of critical buckling of torsionally loaded shells and load-deflection expression of postbuckling states are *** effects of two carbon nanotube reinforced layers,the auxetic core layer,the volume fraction of carbon nanotube on the torsional buckling behavior are examined and remarked.

关键词： Nonlinear postbuckling carbon nanotube reinforced composite cylindrical shell torsion auxetic core

Protective effect of Tetracera scandens *** extract against CCl_4-induced acute liver injury in rats

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Asian Pacific Journal of Tropical Biomedicine 2015年第3期5卷 221-227页

作者： Tung Bui Thanh Hai Nguyen Thanh Hue Pham thi Minh huong Le-thi-Thu huong Duong thi Ly Loi vu Duc School of Medicine and Pharmacy Vietnam National University Hanoi University of Pharmacy

Objective:To investigate the protective potential of ethanolic extracts of Tetracera scandens L.(***) against CCl_4 induced oxidative stress in liver ***:Dried leaf powder of *** was extracted with ethanol and concentrated to yield a dry *** were administered with 100 mg/kg of ethanolic extracts orally once daily for one *** were subsequently administered with a single dose of CCl_4(I mL/kg body weight,intraperitoneal injection).Various assays,such as serum levels of alanine aminotransferase,aspartate aminotransferase,lipid peroxidation,protein oxidation(carbonyl protein group),tumor necrosis factor alpha,catalase,superoxide dismutase,and glutathione peroxidase,were used to assess damage caused by CCl_4 and the protective effects of the ethanol extract on liver ***:Hepatotoxicity induced by CCl_4 was evidenced by a significant increase in serum aspartate aminotransferase and alanine aminotransferase level,lipid peroxidation,protein carbonyl group,and tumor necrosis factor alpha,as well as decreased activity of the hepatic antioxidant enzymes(*** *** glutathione peroxidase).Treatment with ethanolic *** extracts prevented all of these typically observed changes in CCl_4-treated ***:Our findings indicate that *** has a significant protective effect against CCl_4 induced hepatotoxicity in *** may be due to its antioxidant properties.

关键词： Tetracera scandens L Antioxidant Carbon tetrachloride Liver toxicity Lipid peroxidation

Viral co-infections among children with confirmed measles at hospitals in Hanoi,Vietnam,2014

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Asian Pacific Journal of Tropical Medicine 2017年第2期10卷 164-167页

作者： Hang Le Khanh Nguyen Loan Phuong Do Van Thanh thi Trieu Son vu Nguyen Phuong vu Mai Hoang Hien thi Pham Thanh thi Le huong thi Thu Tran Cuong Duc vuong Mai thi Quynh Le National Institute of Hygiene and Epidemiology No 1-Yesrsin streetHanoiVietnam

Objective:To characterize viral co-infections among representative hospitalized measles cases during the 2014 Hanoi ***:Throat swabs were collected from 54 pediatric patients with confirmed measles,and molecular diagnostics performed for 10 additional viral respiratory pathogens(Influenza A/H1N1pdm09;A/H3N2 and influenza B;Parainfluenza 1,2,3;Respiratory Synctial Virus,RSV;human Metapneumovirus,hM PV;Adenovirus and Picornavirus).Results:Twenty-one cases(38.9%) showed evidence of infection with other respiratory viruses:15 samples contained measles plus one additional virus,and 6 samples contained measles plus 2 additional *** was detected as a predominant cause of co-infections(13 cases;24.1%),followed by RSV(6 cases;11.1%),A/H1N1pdm09(3 cases;5.6%),PIV3(3 cases;3.7%),Rhinovirus(3 cases;3.7%) and hM PV(1 case;1.96%).Conclusions:Viral co-infections identified from pediatric measles cases may have contributed to increased disease severity and high rate of fatal *** treatment of measles cases may require control of multiple viral respiratory pathogens.

关键词： Measles virus Respiratory viruses Co-infection

Synthesis and characterization of core/shell structured nanophosphors CePO_4:Tb@LaPO_4 by solvothermal method

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Journal of Rare Earths 2011年第12期29卷 1147-1151页

作者： Dinh Xuan Loc Tran thi Kim Chi Tran Thu huong Nguyen vu Tran Kim Anh Wieslaw Strek Le Quoc Minh Institute of Materials Science Vietnam Academy of Science and Technology Institute of Low Temperature and Structure Research Polish Academy of Sciences(PAN) University of Engineering and Technology

Core/shell structured CePO4：Tb（Ⅲ）@LaPO4 and CePOa：Tb（Ⅲ） were successfully synthesized in tris（2-ethylhexyl） phosphate （TEHP） and diethylene glycol （DEG） solvents for comparison of the two techniques in open air and closed reaction vessel. Morphology and crystal structure of the core/shell nanophosphors were determined by using X-ray diffraction （XRD） and transmission electron microscopy （TEM）, which showed that nanophosphors had diameter of about 5-10 nm with the monoclinic monazite phase. The nanophosphors obtained by close vessel procedure showed smaller size, more homogeneity and pure crystallite. The luminescent measurements were done upon the different excitation wavelengths in ultraviolet region and at room temperatm＇e to elucidate the influences of the used solvents and the reaction temperatures. It was found that CePO4：Tb@LaPO4 preparedby the close vessel synthesis showed the intensity of green band of the transfer from 5D4 to 7F5 energy level, which was strongly increased, and the luminescent decay time was 3.2 ms, which was longer than that of naked CePO4：Tb phosphor.

关键词： solvothermal synthesis luminescence CePOn:Tb CePOa:Tb@LaPO4 rare earths

Investigating the customer trust in artificial intelligence: The role of anthropomorphism, empathy response, and interaction

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CAAI Transactions on Intelligence Technology 2023年第1期8卷 260-273页

作者： Nguyen thi Khanh Chi Nam Hoang vu Foreign Trade University HanoiVietnam Faculty of International Economics Foreign Trade UniversityHanoiVietnam

Artificial intelligence(AI)applications are observed in different industries including the services,where the impressive changing pace is boosted by the technological advances in *** use of AI in the daily work of individuals and in shaping the relationship between firms and customers has resulted in increased efficiency and a higher degree of fascination in *** are,however,customers'fears related to the use of ***,understanding how AI affects customer trust is worth *** study focuses on the AI applications and their impact on communication quality and customer *** features of AI applications investigated in this study include anthropomorphism,empathy response and interaction.A model was first empirically validated through Confirmatory Factor Analysis and tested using Covariance-Based Structural Equation *** were then collected from a survey of 507 customers of two banks and two big telecommunication firms in *** results indicate that anthropomorphism and interaction do not play critical roles in generating customer trust in AI unless they create communication quality with *** ability of empathy response makes customers trust in various service *** application seems to be a good solution for service firms to enhance their relationship with customers in difficult circumstances,including a pandemic *** study delivers implications for enhancing AI adoption in the service firms that intend to innovate their future operations.

关键词： AI anthropomorphism empathy response future orientation interaction

Nutritional Practices among Ethnic Minorities and Child Malnutrition in Mountainous Areas of Central Vietnam

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Food and Nutrition Sciences 2013年第1期4卷 82-89页

作者： Le thi huong vu thi Thu Nga Institute of Preventive Medicine and Public Health Hanoi Medical University Hanoi Vietnam.

Background: Despite the success of National Action Plan on Nutrition program in reducing malnutrition among children under 5 years old in Vietnamin recent years, the rate of malnutrition inVietnamremains higher than that rate in other surrounding countries. The rate is especially high in mountainous areas. this study aims to explore the association between the mother’s nutrition care practice and the nutritional status of their children. Methods: 400 Children under 5 years of age and their mothers from Thanh Hoa—a Northern Province of Vietnam were included in this survey. Weight and height of the children were measured. Information related to the mother’s knowledge and practices pertaining to child health care and nutrition was collected. Results: The malnutrition rate was 29.3% by weight for age score (WAZ), 28.3% by height for age score (HAZ) and 10.0% by weight for height score (WHZ). 27.3% of mothers discarded the colostrum milk. 21.3% of children were fed with chewing rice before breastfeeding. Exclusive breastfeeding up to four months was 17.8% and exclusive breastfeeding rates for 6 months or more was 8.6%. Weaning practice before four months of age was 53.7%. There was an association between malnutrition with mother’s ethnic group, and the frequency of consumption of protein rich food. Conclusion: Malnutrition of ethnic minority children under five years of age is still a public health problem in the central mountainous areas ofVietnam. Inappropriate breastfeeding and weaning practice among ethnic minority women were associated with this high rate. Further effort should continue to improve the nutrition status of ethnic minority children under 5 years of age. Customized, culturally adapted interventions for ethnic minority women to strengthen their nutrition care knowledge, attitude and practice, especially breastfeeding and weaning practice are the key to achieving better nutrition status of their children.

关键词： Malnutrition Children Knowledge and Practice Vietnam

Marker-Assisted Selection of Xa21 Conferring Resistance to Bacterial Leaf Blight in indica Rice Cultivar LT2

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Rice science 2018年第1期25卷 52-56页

作者： Hue thi NGUYEN Quang Hong vu Tan Van MAI Thu thi NGUYEN Lam Duc vu Tung Thanh NGUYEN Long Viet NGUYEN Hien Thu thi vu Hue thi NONG Trung Nguyen DINH Nakano TOSHITSUGU Liet Van vu Crop Research and Development Institute Vietnam National University of Agriculture Trau Qui Gia Lam Hanoi 10000 Vietnam Faculty of Agronomy Vietnam National University of Agriculture Trau Qui Gia Lam Hanoi 10000 Vietnam Faculty of Biotechnology Vietnam National University of Agriculture Trau Qui Gia Lam Hanoi 10000 Vietnam Faculty of land Management Vietnam National University of Agriculture Trau Qui Gia Lam Hanoi 10000 Vietnam Japan International Cooperation Agency 16 Phan Chu Trinh Hoan Kiem Hanoi 10000 Vietnam

Bacterial leaf blight of rice (BLB), caused by Xanthomonas oryzae pv. oryzae, is one of the most destructive diseases in Asian rice fields. A high-quality rice variety, LT2, was used as the recipient ***21, which carries the Xa21 gene, was used as the donor parent. The resistance gene Xa21 was introduced into LT2 by marker-assisted backcrossing. Three Xoo races were used to inoculate the improved lines following the clipping method. Eleven BC_3F_3 lines carrying Xa21 were obtained based on molecular markers and agronomic performance. The 11 lines were then inoculated with the three Xoo races. All the 11 improved lines showed better resistance to BLB than the recipient parent LT2. Based on the level of resistance to BLB and their agronomic performance, five lines (BC_3F_3 5.***.5.1, BC_3F_3 5.***.5.12, BC_3F_3 8.***.6.44, BC_3F_3 9.***.4.1 and BC_3F_3 9.***.4.23) were selected as the most promising for commercial release. These improved lines could contribute to rice production in terms of food security.

关键词： rice backcrossing bacterial leaf blight marker-assisted selection

Longitudinal Flight Dynamic Analysis on Vertical Takeoff of a Tailless Flapping-Wing Micro Air Vehicle

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Journal of Bionic Engineering 2018年第2期15卷 283-297页

作者： Loan thi Kim Au vu Hoang Phan Hoon Cheol Park Department of Advanced Technology Fusion and Artificial Muscle Research Center Konkuk University Seou105029 Korea

this paper first analyzed the longitudinal dynamic behavior during vertical takeoff without control of a Flapping-Wing Micro Air Vehicle （FW-MAV）. The standard linear flight dynamics based on small disturbances from trim condition was not applicable for our analysis because the initial flight condition, which was at rest on the ground, could be such a large disturbance from the trim condition that the linearization is invalid. Therefore, we derived linearized Equations of Motion （EoM） which can treat an untrimmed flight condition as a reference for disturbances. The Computational Fluid Dynamic （CFD） software ANSYS Fluent was used to compute the aerodynamic forces and pitching moments. Three flight modes were found： a fast subsidence mode, a slow subsidence mode and a divergence oscil- latory mode. Due to divergence oscillatory mode, the deviation from the reference flight grew with time; the FW-MAV tumbled without control. The simulation showed for the first 0.5 second after leaving the ground （the time that is long enough for delay of feedback control）, the FW-MAV flew up to a height of 6 cm with small horizontal and pitching motion, which is close to a vertical flight.

关键词： bioinspired FW-MAV flight dynamics vertical takeoff CFD linear theory