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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

STRONG CONVERGENCE OF AN INERTIAL EXTRAGRADIENT METHOD WITH AN ADAPTIVE NONDECREASING STEP SIZE FOR SOLVING VARIATIONAL INEQUALITIES

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Acta Mathematica Scientia 2022年第2期42卷 795-812页

作者： Nguyen Xuan linh Duong Viet THONG Prasit CHOLAMJIAK Pham Anh tuan Luong Van LONG Department of Mathematics Mathematics Falcuty of Information TechnologyNational University of Civil Engineering Division of Applied Mathematics Thu Dau Mot UniversityBinh Duong ProvinceVietnam School of Science University of PhayaoPhayao 56000Thailand Paculty of Mathematical Economics National Economics UniversityHanoi CityVietnam

In this work,we investigate a classical pseudomonotone and Lipschitz continuous variational inequality in the setting of Hilbert space,and present a projection-type approximation method for solving this *** method requires only to compute one projection onto the feasible set per iteration and without any linesearch procedure or additional projections as well as does not need to the prior knowledge of the Lipschitz constant and the sequentially weakly continuity of the variational inequality mapping.A strong convergence is established for the proposed method to a solution of a variational inequality problem under certain mild ***,we give some numerical experiments illustrating the performance of the proposed method for variational inequality problems.

关键词： Inertial method Tseng’s extragradient viscosity method variational inequality problem pseudomonotone mapping strong convergence

Enrichment of hydrogen in product gas from a pilot-scale rice husk updraft gasification system

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Carbon Resources Conversion 2022年第3期5卷 231-239页

作者： Phan Dinh tuan le Minh Quan Vo Trang Nhi Hoang Minh Huong le Thi Kim Phung Daolun Feng Hochiminh City University of Natural Resources and Environment 236B Le Van Sy St.Tan Binh Dist.Ho Chi Minh City 70.000Viet Nam Applied Research Institute for Natural Resources Materialand Environment58/4 Tran Van Du St.Tan Binh Dist.Ho Chi Minh City 70.000Viet Nam Hochiminh City University of Technology 268 Ly Thuong Kiet St.Dist.10Ho Chi Minh City 70.000Viet Nam Vietnam National University-Ho Chi Minh(VNU-HCM) Linh Trung WardThu Duc CityHo Chi Minh CityViet Nam College of Marine Science and Engineering Shanghai Maritime UniversityShanghai 200135PR China

An updraft gasifier was employed to treat 3 kg of dried rice husk per batch with different types of gasifying agents such as air,steam/air,and air with dolomite catalyst addition at various operating *** H2 content,low heating value,and H2/CO ratio in syngas were compared to determine the most effective solution to enhance the H2 production from rice husk *** presence of dolomite in air gasification produced the highest H2 content in the product gas,up to 15.4 mol%,followed by 7.08 and 3.6 mol%when steam/air and air standalone were used as gasifying agents,*** higher low heating value of syngas 5.1 MJ/Nm3 was observed in catalytic air gasification compared to 3.6 MJ/Nm3 when steam was *** optimal operation condition was reported at an airflow rate of 3 m3/h and a catalyst mixing ratio of 15%.

关键词： Rice husk Enriched hydrogen syngas Dolomite Updraft gasifier

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

Coastal Sea Water Quality of Nha Trang Bay, Khanh Hoa, Viet Nam

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Journal of Shipping and Ocean Engineering 2015年第3期5卷 123-130页

作者： Vo Tran tuan linh Duong Trong Kiem Pham Hong Ngoc le Hung Phu Pham Huu Tam le Thi Vinh Department of Hydro-Geo Chemistry Institute of Oceanography Viet Nam Academy of Science and Technology (VAST) Viet Nam

Nha Trang Bay is famous not only because of its beauty, but also of the biodiversity values, especially coral reefs. Thus, the sea water quality monitoring systems are necessary for effective and available managements to protect the ecosystems and for sustainable development. There have been several monitoring systems here but they have been done separately and unconnectedly. This research was done to take an overview and access the status and changes of water quality from 2007-2014. The data obtained rainy seasons over the years showed a quite good environment here. The environment changes were also monitored and there were some changes between seasons and over years, decreasing, increasing, or unobvious trends. However, the difference was not so much; and there was not the sign of environmental degradation in the bay from 2007 to 2014. Besides, the stoichiometric nutrients limitations were initially assessed. Since Si ratios here were always higher compared to N and P, there was not increased potential for non-diatom algal blooms. Together with the recorded nutrients concentration data, it can be said that there was no evidence of eutrophication in the bay. Although there was partial contamination of some parameters at few moments, the sea water quality of Nha Trang bay was still in a good condition （according to Vietnamese and ASEAN criteria）.

关键词： Nha Trang bay sea water quality environmental trend nutrients limitations

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越南海运服务贸易竞争力影响因素研究

越南海运服务贸易竞争力影响因素研究

作者：杜陈俊灵（DO TRAN tuan linh）华东师范大学

学位级别：硕士

在越南运输服务贸易中,海运服务贸易占比重最大,是最为重要的部门。但是它也面临很多问题,其中逆差情况严重、国际竞争力较低一直是最大的问题。研究现有文献,对于影响越南海运服务贸易竞争力的因素研究相对较少,数据库也有限。本文将... 详细信息

在越南运输服务贸易中,海运服务贸易占比重最大,是最为重要的部门。但是它也面临很多问题,其中逆差情况严重、国际竞争力较低一直是最大的问题。研究现有文献,对于影响越南海运服务贸易竞争力的因素研究相对较少,数据库也有限。本文将当前学术界认为影响海运服务贸易竞争力的因素进行归纳,通过定性、定量和实证分析各个因素的影响程度,从而分析关于该问题的理论。对于越南海运服务贸易竞争力的影响因素的研究如何助于分析越南海运服务贸易面临的主要问题,使其能有针对性地采取适合的对策,还有调整贸易的结构,提高越南海运服务贸易在国际市场的竞争力,促进越南海运服务贸易的发展。因此,本文的选题具有一定实践的价值和意义。在论文中,本文运用归纳法来综合文献和理论,从此提出海运服务贸易的概念,竞争力理论和越南海运服务贸易竞争力的现状。在运用回归分析法时,本文选取了几个变量(沿海规模以上港口的外贸货物吞吐量,海运服务贸易出口额,交通运输业的生产总值,货物贸易出口额,远洋运输量,海运贸易开发度),利用Eviews 6软件进行了多元回归分析。本文还运用比较法来比较越南与各国东南亚海运服务贸易竞争力。最后本文使用模型分析法,运用钻石模型分析越南海运服务贸易竞争力。本文通过泼特的钻石模型从生产要素需求要素,相关支特产业与相关产业,企业战略四个要素来分析越南的海运服务贸易竞争力。

关键词：越南海运服务贸易竞争力影响因素对策

Tissue engineering using mesenchymal stem cells with periosteal wrap for bone defect repair in rabbits

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Plastic and Aesthetic Research 2015年第1期2卷 340-345页

作者： Trung-Hau LêThua Dang-Nhat Pham Khanh-linh Lê Minh-tuan Lê Quang-Ton-Quyen Nguyen Phan-Huy Nguyen Ngoc-Vu Tran Ngoc-Luong Nguyen Willy Boeckx Albert Demey Department of Plastic Reconstructive and Hand SurgeryCenter of Orthopaedic and Plastic SurgeryHue Central HospitalHue City 531120Vietnam Department of Hematology Hue Central HospitalHue City 531120Vietnam Department of Biology College of SciencesHue UniversityHue City 521120Vietnam Department of Plastic Surgery Brugmann University HospitalUniversitélibre de Bruxelles1020 BrusselsBelgium

Aim:Mesenchymal stem cells(MSCs)are an excellent potential source of cells for bone tissue engineering due to their excellent renewal ability and osteogenic differentiation *** study was designed to evaluate the bone formation properties of a demineralized cancellous bone scaffold seeded with MSCs,with or without periosteum,in a critical size bone defect model in ***:Rabbit culture-expanded bone marrow(BM)-MSCs were seeded onto a human demineralized cancellous bone(HDCB)*** defects measuring 15 mm in length were created in each radius.A total of 56 bone defects in 28 rabbits were randomly assigned to one of the 4 groups for scaffold implantation:Group 1:HDCB graft only;Group 2:periosteum-wrapped HDCB graft;Group 3:HDCB graft seeded with BM-MSCs and Group 4:periosteum-wrapped HDCB graft seeded with *** rabbits were sacrificed 12 weeks after surgery for gross observation,radiological assessment,histological analyses and biomechanical ***:New bone(NB)formation and bone healing were successfully achieved,both radiologically and histologically,on demineralized cancellous bone graft seeded with *** were improved when BM-MSCs were associated with ***:This study demonstrates that repair of bone defects in a rabbit model can be achieved through bone grafting using BM-MSCs,implanted on a demineralized cancellous bone *** formation of NB was optimized when combined with the preservation of periosteum at the site of injury.

关键词： Bone defects bone marrow bone tissue engineering mesenchymal stem cells periosteum

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： Panax vietnamensis Plant cell suspension culture Plant regulators Yeast extract Casein hydrolyzate Biomass

玉米种质材料遗传多样性的ISSR分析(英文)

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南方农业学报 2011年第9期42卷 1029-1034页

作者： Vu Van Liet Nguyen Thi Thuy linh Nguyen Thi Thuy Vu Thi Bich Hanh Pham Quang tuan Nguyen Thi Phuong Thao 河内农业大学水稻研究所越南河内河内农业大学生物技术系越南河内

【目的】利用ISSR分子标记分析越南北部山区当地玉米种质材料的遗传多样性。【方法】采用ISSR技术和10个引物对从越南和老挝北部山区3个省收集的21份玉米种质材料即12份普通玉米和9份糯玉米的遗传多样性进行分析。【结果】在21份玉米种... 详细信息

【目的】利用ISSR分子标记分析越南北部山区当地玉米种质材料的遗传多样性。【方法】采用ISSR技术和10个引物对从越南和老挝北部山区3个省收集的21份玉米种质材料即12份普通玉米和9份糯玉米的遗传多样性进行分析。【结果】在21份玉米种质材料中可以检测到108个ISSR片段,其多态性为100%。ISSR引物的多态性信息量值为0.10～0.39,每条引物平均为0.24;分辨力为14.29~0.48,平均每条为4.48。除ISSR-T1以外,所有ISSR引物在13份玉米材料中均产生特异性片段。根据聚类分析结果,使用70%的遗传相似性作为切割点,建立了玉米种质材料系统树,21份玉米种质材料被分为3大类。不同玉米材料的相似系数为0.52~0.90.【结论】ISSR标记可提供玉米种质遗传多样性信息,对越南玉米种质材料的收集、保护和育种具有重要作用。

关键词： ISSR分子标记遗传多样性玉米地方品种聚类分析 PCR