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Pesticide Risk Reduction of Vegetable Farmers: A Case Study in Vietnam

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Journal of Environmental Protection 2021年第12期12卷 1055-1068页

作者： nguyen Van Song nguyen Thi Thuy nguyen Cong Tiep Thai Van Ha nguyen dang Que nguyen Thi Xuan Huong Vietnam National University of Agriculture Hanoi Vietnam National Academy of Education Management (NAEM) Hanoi Vietnam National Academy of Public Administration (NAPA) Hanoi Vietnam Vietnam National University of Forestry (VNUF) Hanoi Vietnam

A survey was carried out on farmers cultivating vegetables in Gia Lam district, Hanoi city, Vietnam to investigate their practice in reducing pesticide risks in their farming. Pesticides were an important input in the production there, but the risks of pesticides in recent years had been insignificant. Research results showed that the majority of farmers had relatively well implemented various solutions to reduce pesticides risks in their production, including actively using alternative pest management (IPM) solutions, using biological pesticides, using pesticides properly according to the 4-right pesticide use principle, using labour protection while spraying, and applying treatment measures after spraying. The study suggested solutions to reduce and avoid pesticide risks.

关键词： Pesticides Risk Reduction Vegetable Farming

Effectiveness of Sentinel-1-2 Multi-Temporal Composite Images for Land-Cover Monitoring in the Indochinese Peninsula

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Journal of Geoscience and Environment Protection 2020年第9期8卷 24-32页

作者： nguyen Thanh Hoan Ram C. Sharma nguyen Van Dung dang Xuan Tung Institute of Geography Vietnam Academy of Science and Technology Hanoi Vietnam Graduate University of Science and Technology Vietnam Academy of Science and Technology Hanoi Vietnam Department of Informatics Tokyo University of Information Sciences Chiba Japan Institute of Geological Sciences Vietnam Academy of Science and Technology Hanoi Vietnam

The Indochinese Peninsula, which contains two thirds of the world’s tropical forests, however, is one of the world’s most threatened habitat with some of the highest rates of deforestation and land use changes. Availability of higher resolution satellite data collected by the likes of Landsat 8 and Sentinel-1-2 has brought new opportunities for precise land cover monitoring in recent years. However, utilizing a massive volume of high spatial and temporal resolution data for ecological applications is challenging. One approach is to employ composite images generated from the multi-temporal satellite data. The research was conducted in two study sites located in the Indochinese Peninsula, Laos-Thailand and Vietnam-Cambodia, vulnerable to deforestation and land use changes. We assessed the potential of recently available composite images, such as Biophysical Image Composite (BIC), Forest Cover Composite (FCC), Enhanced Forest Cover Composite (EFCC), and Water Cover Composite (WCC) for the classification and mapping of land cover types. Three machine learning classifiers, k-Nearest Neighbors (KNN), Support Vector Machines (SVM) and Random Forests (RF) were employed and the performance of composite images was evaluated quantitatively with the support of ground truth data. The overall accuracies (Kappa coefficient) obtained from the combination of composite images were 0.92 (0.89) and 0.90 (0.86) for Laos-Thailand, and Vietnam sites respectively. These results highlight effectiveness of the composite images for the classification and mapping of land cover types.

关键词： Satellite Remote Sensing Machine Learning Optical Radar

Surface molecular doping of all-inorganic perovskite using zethrenes molecules

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Nano Research 2019年第1期12卷 77-84页

作者： Arramel Hu Pan Aozhen Xie Songyan Hou Xinmao Yin Chi Sin Tang nguyen T.Hoa Muhammad D.Birowosuto Hong Wang Cuong dang Andrivo Rusydi Andrew T.S.Wee Jishan Wu Department of Physics National University of Singapore2 Science Drive 3Singapore 117542Singapore Centre for Advanced 2D Materials National University of SingaporeBlock S14Level 66 Science Drive 2Singapore 117546Singapore Department of Chemistry National University of Singapore3 Science Drive 3Singapore 117543Singapore CINTRA UMICNRS/NTU/THALES 3288 Research Techno Plaza50 Nanyang DriveLevel 6Border X BlockSingapore 637553Singapore School of Electrical and Electronic Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore Energy Research Institute@NTU(ERI@N) Nanyang Technological UniversityResearch Techno PlazaX-Frontier BlockLevel 550 Nanyang DriveSingapore 637553Singapore Singapore Synchrotron Light Source National University of Singapore5 Research LinkSingapore 1176033Singapore NUS Graduate School for Integrative Sciences and Engineering(NGS) National University of SingaporeSingapore 117456Singapore NUSNNI-NanoCore National University of SingaporeSingapore 117411Singapore Institute of Materials Research&Engineering(IMRE) Agency far ScienceTechnology and Research(A^*STAR)2 Fusionopolis WayInnovisSingapore 138634Singapore

We present an optical and photoelectron spectroscopic study to elucidate the interfacial electronic properties of organic-inorganic semiconductor heterojunctions formed in a kinetically blocked heptazethrene triisopropylsilyl ethynylene (HZ-TIPS) and its homologue,octazethrene (OZ-TIPS) on an all-inorganic perovskite cesium lead bromide (CsPbBr3) *** photoluminescence behavior of the underlying perovskites upon differing molecular doping conditions was *** turns out that the charge transfer dynamics of thermally-evaporated OZ-TIPS molecule exhibited a faster average lifetime than that of the HZ-TIPS case suggesting the importance of the biradical state in the former *** interfacial dipole was formed at the interface due to the competing interaction between the dispersion force of the bulky TIPS-substituent group and the attractive van der Waals interaction at the first few *** spectroscopy of the physisorbed HZ-TIPS shows chemical shifts,which indicates electron transfer from HZ-TIPS molecules to the CsPbBr3 perovskite single *** contrast,the adsorbed OZ-TIPS molecular layer on CsPbBr3 demonstrates the opposite trend indicating a hole transfer *** average molecular orientation as determined by near edge X-ray absorption fine structure (NEXAFS) suggests that the HZ-TIPS molecular plane is generally lifted with respect to the perovskite *** suggest that the nature of the closed-shell electronic ground state of HZ-TIPS could contribute to the formation of interfacial dipole at the molecule/perovskite interface.

关键词： zethrene photoelectron spectroscopy perovskite near edge X-ray absorption fine structure and molecular doping

GC-MS法测定Calophyllum inophyllum L.中的红厚壳素(英文)

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中国天然药物 2011年第6期9卷 429-434页

作者： Ha Minh hien Paul WS Heng nguyen Van Thi nguyen Khac Quynh Cu Vo Thi Bach Hue Institute of Drug Quality Control-Ho Chi Minh City Ho Chi Minh CityVietnam Department of Pharmacy Faculty of ScienceGEA-NUS Pharmaceutical Processing Research LaboratoryNational University of Sin-gaporeSingapore Faculty of Pharmacy University of Medicine and PharmacyHo Chi Minh CityVietnam

AIM:To establish a GC-MS method for the determination of calophyllolide in Calophyllum inophyllum *** its application in quality control of natural ***:Methanolic extract from Calophyllum inophyllum *** *** was isolated,purified and then identified to serve as a chemical marker for development and validation a GC-MS method according to ICH guideline and *** established method was proved to be useful in quality control with the aid of Principle Component Analysis (PCA),a multivariate data analysis ***:The proposed method was selective against mass spectral deconvoluting software *** linear range was from 3.125-50 μg·*** RSD of intra-and inter-day precision variations were less than 3% and the mean recovery was (101.22±1.98)% (RSD=1.95%).PCA was used to indicate a differentiation of batches in production as well as proving that calophyllolide has influence on the discrimination of extracts from different ***:The proposed capillary gas chromatography/mass spectrometric method for the determination of calophyllolide obtained from resin of Calophyllum inophyllum *** oil showed its suitability,simplicity,rapidity and precision,and it can be used for chemical *** is the first time such a technique was reported in *** multivariate data analysis technique was employed to provide an extensive but inclusive method for quality control of the extracts,to ensure consistency for batch to batch of extracts to be used for product development.

关键词： Calophyllum inophyllum Calophyllolide GC-MS Validation

Analytical Results of Cam Ranh-Tuy Phong Fault Characteristics and Its Relation to Mud Eruption in Nam Trung Bo Area, Viet Nam

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Journal of Geological Resource and Engineering 2016年第7期4卷 335-344页

作者： Truong Thanh Phi Van Thom Bui dang Manh nguyen Hanoi University of Natural Resources and Environment Hanoi Vietnam Institute of Geology Viet Nam Academy of Science and Technology Hanoi Vietnam

By analyzing the satellite images, topology map, geology map, geomorphology map, and field survey data, this study has determined the Cam Ranh-Tuy Phong fault in the South Central area, Viet Nam has NE-SW orientation and inclines to SE with high slope angle of 70-80°. During the Pliocene-Quaternary period, the Cam Ranh-Tuy Phong fault is left-lateral movement with the extension mechanisms, which formed the graben have an NE-SW orientation, deposited by Quaternary sediment. The fracture systems and fault are the channels for the mineral water and hot water to move up from the deep zone in the area of Cam Thinh Dong, Ha Nhi, Vinh Hao, Nha Me, Tuy Thinh..., and also to be the channels for the mud material, clay and underground water to move from below zone to the surface to form high mud mounds. The analytical results of clay mud have identified clay mineral composition to be main montmorilonit, illite, kaolinite, calcite, chlorite. The occurrence of montmorilonit minerals in this study area is characterized by the alkali-rich environment. The chemical composition of calcite is determined forming in the environment of with pH 〉 9, characterized by the add climates. Besides, other analytical results of clay mud also identified some minerals, such as： ankerite （Fe, Mg）CO3, calcite and some accessory minerals such as： fluorite, lepidocrokit with the participation hydrothermal process.

关键词： Fault zones mud eruption tectonic activities mineral water hot water.

Households’ Willingness-to-Pay to Reduce the Use of Plastic Bags: Case Study in Viet Nam

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Journal of Environmental Protection 2022年第3期13卷 289-298页

作者： nguyen Van Song nguyen Minh Hieu Vu Ngoc Huyen nguyen dang Que nguyen Van Huong Bui Thi Minh Nguyet Viet Nam National University of Agriculture (VNUA) Ha Noi Viet Nam National Academy of Public Administration (NAPA) Ha Noi Viet Nam Hung Yen University of Technology and Education (UTEHY) Hung Yen Viet Nam Vietnam National University of Forestry Xuan Mai Ha Noi Vietnam

This study used the Binary Logistic regression model to estimate the willingness to pay (WTP) to reduce the use of plastic bags in the daily life of people in the Linh Nam ward. This study notes that households with higher incomes and higher levels of education tend to be more willing to pay. In addition, those who do not have access to information about the harmful effects of plastic bags and receive a higher proposed price often refuse to pay.

关键词： Binary Logistic Regression Willingness to Pay Plastic Bags

Women Empowerment in Household Economic Development:Lessons From Poverty Reduction for Ethnic Minorities in Vietnam

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Psychology Research 2019年第11期9卷 441-450页

作者： dang Thi Hoa nguyen Huu Minh Tran Thi Hong nguyen Thi Tuyet Mai Vietnam Academy of Social Sciences HanoiVietnam

This paper reviews the poverty reduction process in Vietnam and experiences of decision-making empowerment in household economic activities for ethnic minority women in their efforts to reduce *** study analyses data from the Gender Equality Survey,covering 950 households in matrilineal ethnic groups(in the South of Vietnam)in 2018 and life stories of women from Hmong,Tay,Khmer,and Xo dang *** analysis reveals a strong engagement of ethnic minority women(both matrilineal and patriarchal groups)in household economic *** have overcome various cultural barriers to take initiatives in accessing to bank credit,which has been used for developing household *** to their own efforts and supports from the Women’s Union,many ethnic minority households have escaped from poverty,ended food shortage,and started commercial *** a result,ethnic minority women have been increasingly active in both their family and community.

关键词： women empowerment developing countries gender and development identity and culture

Prediction of the Local Scour at the Bridge Square Pier Using a 3D Numerical Model

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Open Journal of Applied Sciences 2014年第2期4卷 34-42页

作者： nguyen Viet Thanh dang Huu Chung Tran Dinh Nghien University of Transport and Communication Hanoi Viet Nam Vietnam Academy of Science and Technology Hanoi Viet Nam

In this paper, the problem on local scour around a single square pier was studied by using both the numerical and physical models. The numerical model for the study is FSUM based on a finite-difference method to solve the Reynolds averaged Navier-Stokes equations (RANS) and the equations for suspended sediment concentration and bed morphology. The computed result was verified through data measured in the experimental flume with a sand bed. In general, the typical features of local scour around the pier were successfully simulated by FSUM, such as stream flow, bow flow, down flow, horseshoe vortex. The comparison between the computation and experiment data shows a quite good fitness. Both numerical model and experiment results show that the maximum scour depth occurs at two front edges of the pier. Although the computed result shows a little bigger scour depth in comparison with the measurement in the physical model, it still confirms the reliability of numerical model in some measure.

关键词： Numerical Modeling Experiment Bridge Square Pier Local Scour FSUM Model

图示理论视角下的口语教学方法研究 ——以越南河内国家大学初级阶段汉语本科生为例

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图示理论视角下的口语教学方法研究 —...

作者：邓文贤（dang Van hien）华中师范大学

学位级别：硕士

汉语口语教学在第二语言教学各语言技能教学中可算是最重要的技能。汉语作为外国语教学也不例外。在教材中,尤其是在外语教材中,图示设计起着辅助教学的作用。若能利用图示描写进行口语教学,其效果特别明显。因此,笔者选择“图示理论视... 详细信息

汉语口语教学在第二语言教学各语言技能教学中可算是最重要的技能。汉语作为外国语教学也不例外。在教材中,尤其是在外语教材中,图示设计起着辅助教学的作用。若能利用图示描写进行口语教学,其效果特别明显。因此,笔者选择“图示理论视角下的口语教学方法研究--以越南河内国家大学初级阶段汉语本科生为例”作为自己的汉语国际教育学硕士学位论文。笔者在相关理论的指导下,采取了调查统计法、分析法、描写法以及对比法等对越南河内国家大学下属外语大学汉语专业本科生初级阶段如何利用图示进行汉语口语教学的现状进行考察与分析,阐明问题。本论文共分六章。第一章是绪论。在此,笔者主要确定本论文的研究意义、目的、方法、研究对象、范围及研究任务,同时对国内外学者们的相关研究进行综述。第二章是相关理论依据。在此,笔者对汉语作为第二语言教学、口语教学、图示理论等相关理论进行概括化,为此项研究奠定基本理论依据。第三章为河内国家大学下属外语大学汉语专业本科生初级阶段利用图示进行口语教学现状。在此,笔者选择个案研究,对所选大学汉语专业本科生的利用图示进行口语教学现状进行考察,考察内容包括教材中图示设计现状、教师的教与学生的学三方面。经考察结果分析阐明其优劣并探讨其成因。第四章是利用图示进行汉语口语教学方法与设计。在此,笔者主要根据第三章的考察结果设计利用图示进行汉语口语教学的方法,包括生词所附的图示、语法点所附的图示以及课文所附的图示。第五章是利用图示进行口语教学的实验分析及教学建议。在此,笔者将所设计的教学方案运用于实际教学,经实验考察与分析,加以肯定利用图示进行汉语口语教学新设计的优势并提出相关的教学建议,力求改善其效果。第六章是结语,在此,笔者进行此项研究的研究结果总结。经研究,笔者已经指出该校现行的教材对越南学生的汉语学习而言缺乏了一定的针对性。图示设计在杨寄洲主编的《对外汉语本科系列教材》前五册以及各项语言知识和技能训练上尚未均衡。该校师生的利用图示进行汉语口语教学从认识到方法都存在着—定的不足之处。在成因分析基础上,笔者设计了如何利用图示进行汉语口语教学的步骤及手段并做了实验及实验结果分析。从而提出必须重新设计教材以便不足现行教材的缺陷,师生必须正确认识到图示设计对教材以及语言教学尤其是口语教学的作用,从而改善教学方法。教师在备课过程中已经要确定教学重点,选择具有代表性的图示进行“再创造”,利用多媒体进行形形色色的图示描写方式,丰富口语教学活动,设计一系列具有启发性的问题启发学生了解图示内容并安排情节,选词组句进行个人演讲和对话、会话,提高学生的观察思维联想以及语言运用能力。教师要扮演组织教学的角色,并出示范文让学生模仿。教师不仅在课堂教学中注重图示描写,而且还要采取任务型教学法引导学生在家预习和复习功课,并将图示描写设在口语课考试内容之中,作为口语考试的重要组成部分,从而有效的进行测验,将口语成绩评估当做推动学生学习动机的鞭策力量。笔者希望本论文能够为越南汉语教学尤其是口语教学提供一份有价值参考资料。

关键词：图示理论汉语口语教学越南学生个案研究图示描写