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Asian Herpetological Research 2015年第1期6卷 66-72页

作者： Dzung Trung le anh Van PHAM Son Hung Lan NGUYEN Thomas ZIEGleR Truong Quang NGUYEN Faculty of Biology Hanoi National University of Education Faculty of Biology and Chemistry Tay Bac University AG Zoologischer Garten Kln Institute of Ecology and Biological Resources Vietnam Academy of Science and Technology

Two amphibian species,Megophrys daweimontisandAmolops vitreus,are recorded for the ifrst time from Vietnam, on the basis of a new amphibian collection from Dien Bien and Son La provinces. In addition, acoustic analysis ofA. vitreus is also provided based on the advertisement calls recorded in Muong Nhe Nature Reserve of Dien Bien Province, Vietnam.

关键词： Amolops vitreus Megophrys daweimontis new records advertisement call Dien Bien Province Son La Province

The future of COVID-19 vaccination rates for children

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Asian Pacific Journal of Tropical Medicine 2022年第9期15卷 381-382页

作者： Giao Huynh Kimberly H.Nguyen Han Thi Ngoc Nguyen tuan Diep Tran Pham le An Faculty of Public Health University of Medicine and Pharmacy at Ho Chi Minh CityHo Chi Minh CityVietnam Department of Public Health and Community Medicine Tufts University School of MedicineBostonMAUSA Infection Control Department University Medical Center Ho Chi Minh CityHo Chi Minh CityVietnam Faculty of Medicine University of Medicine and Pharmacy at Ho Chi Minh CityHo Chi Minh CityVietnam Family Medicine Training Center University of Medicine and Pharmacy at Ho Chi Minh CityHo Chi Minh CityVietnam

The COVID-19 pandemic has been ongoing for over two years since the first case was reported in the end of January *** has successfully controlled the pandemic through its vaccination campaign,targeted messages and applications of various public health interventions including social distancing,quarantining,masking,and hand washing,which have made some significant achievements in reducing hospitalizations and deaths[1].

关键词： vaccination targeted COV

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

Gravitationally lensed extended sources: the case of QSO RXJ0911

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Research in Astronomy and Astrophysics 2013年第7期13卷 803-814页

作者： Do Thi Hoai Pham Tuyet Nhung Pham tuan anh Frederic Boone Pierre Darriulat Pham Ngoc Diep Pham Ngoc Dong Nguyen Van Hiep Nguyen Thi Thao VATLY INST179Hoang Quoc VietCau GiayHanoiVietnam IRAP 14avenue Edouard BelinF31400 ToulouseFrance

After a brief reminder of the mechanism of gravitational lensing of ex- tended sources, the particular case of the host galaxy of QSO RXJ0911, a high red-shift （z - 2.8） quadruply imaged quasar, is explored. The non linearity of the problem, together with the proximity of the source to a cusp of the lens inner caustic, has impor-tant consequences on the dependence of the image appearance on the size and shape of the source. Their expected main features and their interpretation in terms of source extension and shape are investigated in a spirit of simplicity and in preparation for the analysis of high sensitivity and spatial resolution images that will soon be within reach with the completion of the Atacama Large Millimeter/submillimeter Array （ALMA）. In particular, the information on source size carded by relative image brightness is dis-cussed. Extension of the results to other types of quadruply imaged quasars is briefly considered.

关键词： gravitational lensing - galaxies: high-redshift

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

Assessing Satellite-Based Precipitation Products to Create Flood Forecasting in the Da River Basin, Vietnam

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Journal of Geoscience and Environment Protection 2019年第11期7卷 113-123页

作者： le Viet Son Luong Ngoc Chung Bui tuan Hai Sai Hong anh Nguyen Duy Quang Division for Water Resources Planning for the North Region Institute of Water Resources Planning Hanoi Vietnam Board of directors Institute of Water Resources Planning Hanoi Vietnam Department of Agro-Environmental Sciences Graduate School of Bioresource and Bioenvironmental Sciences Kyushu University Fukuoka Japan

The Da River Basin is an international basin where available access to hydrological data is limited;it has a total basin area of 52,900 km2, about 50% of the area in which it is located, Vietnam. The Da River is the primary source of water for agriculture in 25 provinces and cities, and the primary source of drinking water for more than 30 million people in both urban and rural areas. It has huge economic and historical value. However, flood forecasting for the Da River basin has not been adequately addressed yet because of the challenge of the inconsistency, scarcity, poor spatial representation, as well as difficult access and incompleteness of the availability of ground observed rainfall data. In this research, the IFAS model has been utilized to assess the benefits of using satellite-based precipitation products to create flood forecasting for the whole research area. The results showed that the Integrated Flood Analysis System (IFAS) model was able to integrate the satellite-based precipitation products for simulating the flood event in the Da River basin. Also, the 3B42RT algorithm showed a definite improvement in reproducing the flood peak and low flow very well in the research area. These results could be used to enhance the effectiveness of flood management strategy in the basin.

关键词： IFAS Flood Flow 3B42RT and GSMaP Algorithm

Climate change and groundwater resources in Mekong Delta, Vietnam

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Journal of Groundwater Science and Engineering 2017年第1期5卷 76-90页

作者： Duong D Bui Nghia C Nguyen Nuong T Bui anh T T le Dao T le National Center for Water Resources Planning and Investigation MONRE Vietnam Tokyo Metropolitan University Japan Center for Environmental Fluid Dynamics Hanoi University of Science Vietnam

Groundwater resources have considerable influences on the human population and socioeconomic development of Vietnam and the Mekong River Delta(MRD). This paper presents an overview of the relationship between climate change and groundwater in the MRD, including the challenges, strategies and technical measures. Our results showed that groundwater levels are related to other climate and hydrological variables(i.e., rainfall, river levels, etc.); therefore, the impacts of climate change on the groundwater resources of the Mekong delta are significant, especially on groundwater recharge. Based on the results of this study, it is recommended that groundwater development in the future should focus on reducing groundwater harvesting, enhancing groundwater quantity by establishing artificial works and exploiting surface water. This study suggests that the Artificial Neural Network(ANN) model is an effective tool for forecasting groundwater levels in periods of 1 month and 3 months for aquifers in the natural and tidal regime areas of the delta.

关键词： Groundwater management Climate change ANN model Mekong River Delta

Optimum Determination of Partial Transmission Ratios of Mechanical Driven Systems Using a V-belt and a Three-Step Helical Gearbox

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Journal of Environmental Science and Engineering(B) 2017年第6期6卷 328-331页

作者： Dang anh tuan Nguyen Khac tuan Vu Ngoc Pi Mechanical Engineering Faculty Thai Nguyen University of Technology Thai Nguyen 23000 Vietnam Automotive and Power Machinery Faculty Thai Nguyen University of Technology Thai Nguyen 23000 Vietnam

This paper introduces a new study on the optimum calculation of partial transmission ratios of a mechanical drive system using a V-belt and a three-step helical gearbox in order to get the minimum size of the system. The chosen objective function was the cross section dimension of the system. In solving the optimization problem, the design equation for pitting resistance of a gear set was investigated and equations on moment equilibrium condition of a mechanic system including a V-belt and three helical gear units and their regular resistance condition were analysed. From the results of the study, effective formulas for determination of the partial ratios of the V-belt and three-step helical gearboxes were introduced. As using explicit models, the partial ratios can be determined accurately and simply.

关键词： Transmission ratio gearbox design optimum design V-belt drive helical gearbox.

Calibration of a neutron dose rate meter in various neutron standard fields

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Nuclear Science and Techniques 2020年第6期31卷 75-82页

作者： tuan Khai Nguyen Hoai-Nam Tran Quynh Ngoc Nguyen Thi My Linh Dang Van Loat Bui Thiansin Liamsuwan Ngoc-Thiem le Vietnam Agency for Radiation and Nuclear Safety 113 Tran Duy HungHanoi 100000Vietnam Institute of Fundamental and Applied Sciences Duy Tan UniversityHo Chi Minh 700000Vietnam Faculty of Natural Sciences Duy Tan University3 Quang TrungDa Nang 550000Vietnam Institute for Nuclear Science and Technology VINATOM179 Hoang Quoc VietHanoi 100000Vietnam Faculty of Physics VNU University of Science334 Nguyen TraiHanoi 100000Vietnam Nuclear Research and Development Division Thailand Institute of Nuclear TechnologyOngkharakNakorn NayokThailand 7 Faculty of Medicine and Public HealthHRH Princess Chulabhorn College of Medical ScienceChulabhorn Royal AcademyBangkokThailand

This paper presents the calibration of a neutron dose rate meter and the evaluation of its calibration factors(CFs)in several neutron standard fields(i.e.,two standard fields with bare sources of252Cf and241Am-Be,and five simulated workplace fields with241Am-Be moderated sources).The calibration in standard fields with bare sources was conducted by following the recommendations of the ISO 8529 *** measured total neutron ambient dose equivalent rates,denoted as H*(10)tot,were analyzed to obtain direct components,denoted as H*(10)dir,using a reduced fitting *** CF was then calculated as the ratio between the conventional true value of the neutron ambient dose equivalent rate in a free field,denoted as H*(10)FF,and the value of H*(10)*** contrast,in the simulated workplace neutron fields,the calibration of the neutron dose rate meter was conducted by following the ISO 12789 *** CF was calculated as the ratio between the values of H*(10)totmeasured by a standard instrument(i.e.,Bonner sphere spectrometer)and the neutron dose rate *** CF values were obtained in the range of 0.88–*** standard uncertainties(k=1)of the CFs were determined to be in the range of approximately 6.6–13.1%.

关键词： Neutron standard fields Neutron dose rate meter Calibration factor 252Cf source 241AmBe source

Micro-satellite Constellation The Challenges and the Possible Contribution of VNSC

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Journal of Geological Resource and Engineering 2014年第2期2卷 107-110页

作者： Vu Viet Phuong Pham anh tuan Vietnam National Satellite Center Vietnam Academy of Science and Technology Hanoi 10000 Vietnam

In response to the fast evolution of micro-satellite, the ＂AMC （Asian micro-satellite consortium）＂ is established to promote and accelerate the development of micro-satellite and its applications including future projects such as ＂a super constellation＂. Through this paper, we want to share our views on the challenges facing implementation of micro constellation by many institutions with their benefit requirements and also the possible contribution from Vietnam National Satellite Center to this project.

关键词： Micro-satellite constellation continuous observation Asian satellite.