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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 (<i>δ</i><sup>13</sup>C)

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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

GLOBALLY ATTRACTING SOLUTIONS TO IMPULSIVE FRACTIONAL DIFFERENTIAL INCLUSIONS OF SOBOLEV TYPE

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Acta Mathematica Scientia 2017年第5期37卷 1295-1318页

作者： Van Hien LE Dinh Ke tran Trong Kinh CHU Department of Mathematics Hanoi National University of Education 136 Xuan ThuyCau GiayHanoiVietnam Department of Mathematics Hanoi Pedagogical University No.2VinhphucVietnam

We study a generalized Cauchy problem associated with a class of impulsive fractional differential inclusions of Sobolev type in Banach spaces. Our aim is to prove the existence of a compact set of globally attracting solutions to the problem in question. An application to fractional partial differential equations subject to impulsive effects is given to illustrate our results.

关键词： globally attracting solution impulsive condition nonlocal condition condensing map measure of non-compactness MNC-estimate

Novel Time Series Bagging Based Hybrid Models for Predicting Historical Water Levels in the Mekong Delta Region, Vietnam

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Computer Modeling in Engineering & Sciences 2022年第6期131卷 1431-1449页

作者： Nguyen Thanh Hoan Nguyen Van Dung Ho Le Thu Hoa Thuy Quynh Nadhir Al-Ansari tran Van Phong Phan Trong Trinh Dam Duc Nguyen Hiep Van Le Hanh Bich thi Nguyen Mahdis Amiri Indra Prakash Binh Thai Pham Institute of Geography Vietnam Academy of Science and TechnologyHanoi10000Viet Nam Department of Civil Environmental and Natural Resources EngineeringLulea University of TechnologyLulea97187Sweden Institute of Geological Sciences Vietnam Academy of Science and Technology(VAST)Dong DaHanoi10000Viet Nam University of transport Technology Thanh XuanHa Noi10000Viet Nam Department of Watershed&Arid Zone Management Gorgan University of Agricultural Sciences&Natural ResourcesGorgan***Iran DDG(R)Geological Survey of India Gandhinagar382010India

Water level predictions in the river,lake and delta play an important role in flood *** year Mekong River delta of Vietnam is experiencing flood due to heavy monsoon rains and high *** subsidence may also aggravate flooding problems in this ***,accurate predictions of water levels in this region are very important to forewarn the people and authorities for taking timely adequate remedial measures to prevent losses of life and *** are so many methods available to predict the water levels based on historical data but nowadays Machine Learning(ML)methods are considered the best tool for accurate *** this study,we have used surface water level data of 18 water level measurement stations of the Mekong River delta from 2000 to 2018 to build novel time-series Bagging based hybrid ML models namely:Bagging(RF),Bagging(SOM)and Bagging(M5P)to predict historical water levels in the study *** of the Bagging-based hybrid models were compared with Reduced Error Pruning Trees(REPT),which is a benchmark ML *** data of 19 years period was divided into 70:30 ratio for the *** data of the period 1/2000 to 5/2013(which is about 70%of total data)was used for the training and for the period 5/2013 to 12/2018(which is about 30%of total data)was used for testing(validating)the *** of the models was evaluated using standard statistical measures:Coefficient of Determination(R2),Root Mean Square Error(RMSE)and Mean Absolute Error(MAE).Results show that the performance of all the developed models is good(R2>0.9)for the prediction of water levels in the study ***,the Bagging-based hybrid models are slightly better than another model such as ***,these Bagging-based hybrid time series models can be used for predicting water levels at Mekong data.

关键词： Computational techniques bagging water level time series algorithms

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现阶段越南大众体育的管理体制研究

武术研究 2018年第2期3卷 131-134页

作者：阮氏春芳越南北宁体育大学管理教研室越南北宁省121300

文章采用文献资料法、访谈法、社会调查法等研究方法调查、了解现阶段越南大众体育的管理体制。结果表明:现阶段,越南大众体育管理体制包括政府管理系统和社会管理系统,但以政府管理系统为主。政府管理系统从中央级覆盖到县级,乡镇级还... 详细信息

文章采用文献资料法、访谈法、社会调查法等研究方法调查、了解现阶段越南大众体育的管理体制。结果表明:现阶段,越南大众体育管理体制包括政府管理系统和社会管理系统,但以政府管理系统为主。政府管理系统从中央级覆盖到县级,乡镇级还没有正式的大众体育政府管理机构,只有文、社干部。在人力、财力、物力等各方面的资源,越南大众体育政府管理系统的实力还比较薄弱。社会管理系统已初步成立,但处于有名无实,基本上没有实际活动,大部分还是各类政府管理机构的"延伸",带有"半官方"性质的状况。政府与社会管理系统之间职能交叉、混乱,缺乏协调的运行机制。

关键词：越南管理体制大众体育现阶段

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河内与北京城市交通运输系统比较研究

河内与北京城市交通运输系统比较研究

作者：陈秋芳（tran Thu phuong）北京交通大学

学位级别：硕士

随着经济的高速增长,各个城市的交通需求也在快速增长。虽然政府不断加大交通基础设施建设力度,但是仍旧滞后于交通需求的迅猛增长,导致了一系列诸如城市交通拥挤,交通事故不断增加,环境污染加剧等城市交通问题的出现。本文的研究目的... 详细信息

随着经济的高速增长,各个城市的交通需求也在快速增长。虽然政府不断加大交通基础设施建设力度,但是仍旧滞后于交通需求的迅猛增长,导致了一系列诸如城市交通拥挤,交通事故不断增加,环境污染加剧等城市交通问题的出现。本文的研究目的就是为了深入了解城市交通运输系统的发展现状,找出问题存在的根源,并相应地提出未来城市交通运输系统的发展对策和建议。本论文首先系统分析了城市综合交通运输系统的相关理论,包括城市综合交通运输体系的定义、发展框架、发展内容以及发展现状和存在的问题。从整体上找出城市交通运输发展的症结,提出保障性的原则和未来大城市的交通模式选择。然后分别对北京市和河内市的交通运输系统现状进行综合分析,包括社会经济状况、交通基础设施、交通流量、客货运输、交通环境和安全以及智能交通等多个方面,从而找出城市交通运输系统存在的问题和影响因素。最后在详细解读国外典型城市交通运输发展状况的基础上,对北京和河内的城市交通运输系统发展情况给出相应的发展启示,这对北京市和河内市未来的交通运输系统发展具有一定的指导意义。

关键词：交通运输系统分析交通模式基础设施公交优先交通需求管理交通安全

The Effect of ENSO on Hydrological Structure and Environment in the South Central Coast-Vietnam

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Journal of Marine Science 2020年第1期2卷 10-16页

作者： Pham xuan Duong Hoang Trung Du Vo tran Tuan Linh To Duy Thai Phan Minh Thu Institute of Oceanography Vietnam Academy of Science and Technology(VAST)Nha TrangVietnam State Key Laboratory of Estuarine and Coastal Research(SKLEC) East China Normal UniversityShanghaiChina Graduate University of Science and Technology VASTHa NoiVietnam

ENSO(El Niño-Southern Oscillation)phenomena have impacted on the hydrodynamic regime and environmental factors of the tropical ocean in *** case of Vietnamese South-Central Waters,impacts of ENSO only focused on issues of changing seasonal wind,seawater temperature anomalies,changing of water masses as the air-sea *** on several data sets collecting in the period of 2003-2017,new finding of seawater temperature,salinity and environmental factors was identified in the water masses of Vietnamese South-Central *** highest salinity was 35.4‰.During the El Nino event,increasing water temperature and salinity caused to move the deeper water masses to be closer to the sea surface than that initial depth in the neutral *** the La Nina event,the temperature of most water masses reduced by 0.1-3.0℃,and then these water masses could be affected to the deeper *** the phase from strong ENSO event towards the neutral time,nutrient salts of the 4 water masses were lower concentration in the neutral year,causing the lack of phosphorus in sea surface water masses.

关键词： Effect of ENSO Hydrodynamic regime South Central Coast-Vietnam

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越南初中级汉语口语教材分析

越南初中级汉语口语教材分析

作者：陈有芳柔瑞（tran Huu phuong Nhu Thuy）上海师范大学

学位级别：硕士

越南作为中国的邻国,与中国在文化和经济上的关系非常密切。近年来,中越之间的贸易关系愈发紧密,汉语和汉语人才变得越来越重要。虽然越南的很多高校都开设了中文专业,但在汉语教材编写方面的投入比较有限,导致教学质量受到很大影响。... 详细信息

越南作为中国的邻国,与中国在文化和经济上的关系非常密切。近年来,中越之间的贸易关系愈发紧密,汉语和汉语人才变得越来越重要。虽然越南的很多高校都开设了中文专业,但在汉语教材编写方面的投入比较有限,导致教学质量受到很大影响。尤其是缺少更多的高质量、有针对性的口语教材,导致口语、阅读等课堂教学并无显著差异。所以,本文认为在开展汉语口语教学时,教师如果能够在教材上有更多的选择,再辅以合适的教学方法,教学效果会有很大改进。本文在进行研究时,主要针对越南汉语初中级口语教材的使用和编写情况和使用者对教材的使用需求进行探讨分析,研究框架主要分为五个部分。第一章,基于宏观层面,阐述本文的研究背景和意义,对国内外学者在编写本土化教材方面的成果进行梳理总结,并对本文开展研究的方法与思路等进行了简单的介绍。第二章,阐述越南汉语口语教材编写和使用情况,主要研究两个部分的内容。其一,对越南汉语教学概括进行简单的介绍。其二,本章对越南汉语口语教材出版情况和使用现状进行研究分析并厘清越南汉语口语教材的特点以及存在的问题。第三章,从使用者角度出发,利用问卷调查方法,调查越南编写和使用汉语教材存在的问题,以便更好地掌握学习者对于教材的实际需求。第四章,分析当前在越南开展汉语口语教学中使用较为广泛的《汉语会话301句》的编排结构、课文内容、词汇、语法和练习方面的编写特点,并在此基础上探讨该教材的优缺点。最后,就当前越南在编写汉语及口语教材存在的问题,提出相关建议和措施。

关键词：越南汉语口语教材编写使用需求

Assessing and Forecasting Saline Intrusion in theVietnamese Mekong Delta Under the Impact of Upstreamflow and Sea Level Rise

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Journal of Environmental Science and Engineering(B) 2019年第5期8卷 174-185页

作者： tran xuan Hai Vu Van Nghi Vu Hoang Hung Do Ngoc Tuan Dang Thanh Lam Can Thu Van Institute for Science and Technology Innovation Ho Chi Minh City 700000Vietnam University of Science Vietnam National UniversityHo Chi Minh City 700000Vietnam Thuyloi University Ha No 100000Vietnam Southern Institute for Water Resources Planning Ho Chi Minh City 700000Vietnam Ho Chi Minh City University of Natural Resources and Environment Ho Chi Minh City 700000Vietnam

Saline intrusion is a hot issue and has always been of concern in the VMD(Vietnamese Mekong Delta),especially in the context of many changes of impact factors such as upstream flows and SLR(Sea Levels Rise).Vulnerability to changes in the upstream flows and SLR ismust-have reasons for updated and interpreted *** information is used for exploiting of soil and water *** 11 model was successfully applied to assess the saline *** study provided the picture of the saline intrusion in the dry season from January to May in the VMD in the existing situation(2015 and 2016)and the future(2030 and 2050)under the impact of flow at Kratie in various frequencies of 18%,50%and 85%based on the time series of 2001-2016,and SLR according to RCP(Representative Concentration Pathway)4.5 scenario of MONRE(Ministry of Natural Resources and Environment)of Vietnam issued in *** results show that in the year 2015 the ASI(Saline Intrusion Area)in the VMD was relatively low due to moderate tidal level and high Kratie discharge(P=18%).The scenario like the situation in 2016 and in the future ASI increased significantly compared to the 2015 baseline scenario which shows that the VMD is very vulnerable to saline *** on multivariate regression analysis,the study also presented the formulas for the relationship between the ASI of 0.25 g/L,2.5 g/L and 4.0 g/L thresholds and the impact factors such as the average discharge at Kratie and the maximum daily tidal level in East Coast during the dry season from January to *** an adjusted R2 at 0.913-0.974,these formulas are believed to be reliable for predicting ASIs based on the Kratie flow and the East Coast tidal level.

关键词： Saline intrusion sea level rise upstream flow VMD

DENSITY ESTIMATES FOR SOLUTIONS OF STOCHASTIC FUNCTIONAL DIFFERENTIAL EQUATIONS

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Acta Mathematica Scientia 2019年第4期39卷 955-970页

作者： Nguyen Tien DUNG Ta Cong SON tran Manh CUONG Nguyen Van TAN Trinh Nhu QUYNH Department of Mathematics FPT University Hoa Lac High Tech Park Hanoi Vietnam Department of Mathematics VNU Hanoi University of Science 334 Nguyen Trai Thanh Xuan Hanoi Vietnam Department of Foundation Academy of Cryptography Techniques Hl Chien Thang Thanh Tri Hanoi Vietnam Military Information Technology Institute 17 Hoang Sam Cau Giay Hanoi Vietnam

In this article, we investigate the density of the solution to a class of stochastic functional differential equations by means of Malliavin calculus. Our aim is to provide upper and lower Gaussian estimates for the d... 详细信息

关键词： Stochastic functional differential equations density estimates Malliavin calculus