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Advances in Remote Sensing 2016年第4期5卷 284-295页

作者： Nguyen Thi quynh Trang le Quang Toan Tong Thi Huyen Ai Nguyen Vu Giang Pham Viet Hoa Space Technology Institute Vietnam Academy of Science and Technology Hanoi Vietnam Ho Chi Minh Institute of Resource Geography Vietnam Academy of Science and Technology Ho Chi Minh City Vietnam

Many researches have been performed comparing object-based classification (OBC) and pixel-based classification (PBC), particularly in classifying high-resolution satellite images. VNREDSat-1 is the first optical remote sensing satellite of Vietnam with resolution of 2.5 m (Panchromatic) and 10 m (Multispectral). The objective of this research is to compare two classification approaches using VNREDSat-1 image for mapping mangrove forest in Vien An Dong commune, Ngoc Hien district, Ca Mau province. ISODATA algorithm (in PBC method) and membership function classifier (in OBC method) were chosen to classify the same image. The results show that the overall accuracies of OBC and PBC are 73% and 62.16% respectively, and OBC solved the “salt and pepper” which is the main issue of PBC as well. Therefore, OBC is supposed to be the better approach to classify VNREDSat-1 for mapping mangrove forest in Ngoc Hien commune.

关键词： Object-Based Classification Pixel-Based Classification VNREDSat-1 Mangrove Forest Ca Mau

不同参数下封闭矩形声腔的结构-声耦合特性分析

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东南大学学报（自然科学版） 2013年第3期43卷 503-508页

作者：王园张建润顾伟黎文琼东南大学机械工程学院南京211189

基于模态耦合分析法建立了板-声腔耦合系统的自由振动模型,分析了声腔深度对耦合系统共振频率、模态衰减时间的影响,并详细研究了声腔深度变化时,板模态和声腔模态耦合过程中的能量传递、系统共振频率和模态衰减时间的改变.分析表明,声... 详细信息

基于模态耦合分析法建立了板-声腔耦合系统的自由振动模型,分析了声腔深度对耦合系统共振频率、模态衰减时间的影响,并详细研究了声腔深度变化时,板模态和声腔模态耦合过程中的能量传递、系统共振频率和模态衰减时间的改变.分析表明,声腔深度改变时,影响声腔模态与板模态传递因子大小的因素有声腔深度和对应的耦合前共振频率差.在声腔模态与板模态出现强耦合的声腔深度附近,对应腔控模态和板控模态的共振频率出现跃变现象,而在耦合最强的声腔深度处耦合系统模态衰减时间趋于相等,声腔声场和板振动之间的能量传递最大.

关键词：耦合特性共振频率模态衰减时间传递因子

Characteristics of the gene encoding pyrroline-5-carboxylate synthase(P5CS) in Vietnamese soybean cultivars(Glycine max ***)

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Characteristics of the gene encoding pyrroline-5-carboxylate...

Ethanol extracts of Scutellaria baicalensis protect against lipopolysaccharide-induced acute liver injury in mice

International Conference on Biology, Environment and Chemistry（ICBEC 2010）

作者： Chu Hoang Mau Nguyen Thi Thuy Huong Chu Hoang Lan Nguyen Tuan anh le Van Son Chu Hoang Ha Dept.of Genetics Faculty of Biology Thainguyen University Dept.of Genetics Faculty of Biology Vietnam National University of Science Dept.of Environment Faculty of Agricultural Environment Thainguyen University Lab.of Plant Cell Biotechnology Institute of Biotechnology

ISBN: (纸本)9789810886424

This research evaluates the ability of six soybean local cultivars and a control cultivar(DT84) to tolerate severe *** this research,SL5 and SL6 have the most stress tolerance while DT84 and SL1 have the least stress *** have isolated P5CS gene as it relates to stress tolerance by using PCR with *** results show that the size of the P5CS gene of the studied cultivars is 2,148 bp,which encodes for 715 amino *** these proteins are compared with the P5CS proteins of the other species,the result shows that the isolated P5CS proteins have a higher identity than other bean *** are located on the same branch of the phylogenetic ***(Pro) is one of the most accumulated osmolytes in salinity and water deficit conditions in plants.P5CS is a key regulatory enzyme involved in prolin biosynthesis in plants and is subject to feedback inhibition by *** conserved aspartate residue at 126 and the phenylalanine at 129 are involved in the feedback inhibition by Pro binding.A gene encoding a feedback insensitive P5CS enzyme was obtained by mutating the P5CS *** mutation was due to a change of an aspartate at position 125 to alanine in the *** mutated gene was cloned in pBT vector and *** gene will be transfered to plants to increase the level of proline overproduction and to enhance the drought tolerance ability.

关键词： drought,Glycine max,point mutation,P5CS,proline.

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Asian Pacific Journal of Tropical Biomedicine 2015年第9期5卷 733-738页

作者： Hai Nguyen Thanh Hue Pham Thi Minh Tuan anh le Huong Duong Thi Ly Tung Nguyen Huu Loi Vu Duc Thu Dang Kim Tung Bui Thanh School of Medicine and Pharmacy Vietnam National University Hanoi University of Pharmacy

Objective: To investigated the protective potential of ethanol extracts of Scutellaria baicalensis(S. baicalensis) against lipopolysaccharide(LPS)-induced liver injury. Methods: Dried roots of S. baicalensis were extracted with ethanol and concentrated to yield a dry residue. Mice were administered 200 mg/kg of the ethanol extracts orally once daily for one week. Animals were subsequently administered a single dose of LPS(5 mg/kg of body weight, intraperitoneal injection). Both protein and m RNA levels of cytokines, such as tumor necrosis factor alpha, interleukin-1β, and interleukin-6 in liver tissues were evaluated by ELISA assay and quantitative PCR. C yclooxygenase-2, inducible nitric oxide synthase, and nuclear factor-κB protein levels in liver tissues were analyzed by western blotting. Results: Liver injury induced by LPS signifi cantly increased necrosis factor alpha, interleukin-1β, interleukin-6, cyclooxygenase-2, inducible nitric oxide synthase, and nuclear factor-κB in liver tissues. Treatment with ethanol extracts of S. baicalensis prevented all of these observed changes associated with LPS-induced injury in liver ***: Our study showed that S. baicalensis is potentially protective against LPS-induced liver injury in mice.

关键词： Scutellaria baicalensis Lipopolysaccharide Liver injury Cytokine Nuclear factor-κB

Experimental Determination of Optimum Exchanged Diameter in Surface Grinding Process

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Journal of Environmental Science and Engineering(A) 2017年第2期6卷 85-89页

作者： Vu Ngoc Pi Luu anh Tung le Xuan Hung Nguyen Van Ngoc Mechanical Engineering Faculty Thai Nguyen University of Technology Thai Nguyen 250000 Vietnam Mechanical Engineering Faculty Ha Tinh Intermediate Vocational School Ha Tinh 480000 Vietnam

In vivo anticancer activity of maesopsin 4—O— β—glucoside isolated from leaves of Artocarpus tonkinensis *** Gagnep

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Asian Pacific Journal of Tropical Medicine 2016年第4期9卷 343-348页

作者： Trinh Thi Thuy Dao Duc Thien Tran Quang Hung Nguyen Thanh Tam Nguyen Thi Hoang anh Nguyen Thi Nga Nguyen Thi Cuc le Phuong Mai Tran Van Sung Domenico V.Delfino Do Thi Thao Institute of Chemistry.Vietnam Academy of Science and Technology Institute of Biotechnology Vietnam Academy of Science and Technology National Research Council Canada Measurement Science and Standards1200 Montreal RoadBuilding M-12.Ottatca.Ontario KIA OR6 Department of Medicine University of PerugiaPiazzale Gambuli.S.Andrea delle Fratte

Objective:To investigate the antitumor effect of maesopsin 4-O-β-glucoside(TAT2) isolated from the leaves of Artocarpus tonkinensis(***) *** ***:The antitumor activity of TAT2 was evaluated in lewis lung carcinoma(LLC) tumor-bearing ***/c mice had tumors induced by implantation with 2× 10~6 LLC cells into the subcutaneous right posterior ***-bearing mice were treated orally with a range of doses of TAT2 and a standard drug,*** were observed for tumor growth and mortality *** was collected to determine hematological and biochemical *** TAT2 was isolated from an ethanolic extract of *** *** structure was determined by MS and NMR spectroscopy,and identified as *** compound did not show acute toxicity at the highest dose tested(2 OIK) mg/kg body weight).TAT2 exhibited antitumor activity by decreasing tumor growth,increasing the survival rale,and ameliorating some hematological and biochemical parameters at doses of 100 and 200 mg/kg body weight(Plear antitumor *** to its bioavailability and low toxicity,and the fact that it could be isolated in a large scale from *** leaves,the compound shows promise as a potential anticancer drug.

关键词： Artocarpus tonkinensis BALB/c Hematological parameters lewis lung carcinoma Maesopsin 4-0-β-glucoside

A Neural-network-based Approach to Study the Energy-optimal Hovering Wing Kinematics of a Bionic Hawkmoth Model

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Journal of Bionic Engineering 2019年第5期16卷 904-915页

作者： anh Tuan Nguyen Ngoc Doan Tran Thanh Trung Vu Thanh Dong Pham Quoc Tru Vu Jae-Hung Han Faculty of Aerospace Engineering Le Quy Don Technical University236 Hoang Quoc VietVietnam Office of International Cooperation Le Quy Don Technical University236 Hoang Quoc VietVietnam Department ofAerospace Engineerings Korea Advanced Institute of Science and Technology Daejeon 34141Republic ofKorea

This paper presents the application of an artificial neural network to develop an approach to determine and study the energy-optimal wing kinematics of a hovering bionic hawkmoth model.A three-layered artificial neural network is used for the rapid prediction of the unsteady aerodynamic force acting on the wings and the required *** this artificial network is integrated into genetic and simplex algorithms,the running time of the optimization process is reduced *** validity of this new approach is confirmed in a comparison with a conventional method using an aerodynamic model based on an extended unsteady vortex-lattice method for a sinu soidal wing kinematics *** studying the obtained results,it is found that actual hawkmoths do not hover under an energy-optimal ***,by tilting the stroke plane and lowering the wing positions,they can compromise and expend some energy to enhance their maneuverability and the stability of their flight.

关键词： optimal hovering wing kinematics artificial neural network insect flight genetic algorithm unsteady vortex-lattice method bionics

Use of Sequential, Single and Kinetic Extractive Schemes to Assess Cadmium (Cd) and lead (Pb) Availability in Vietnamese Urban Soils

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American Journal of Analytical Chemistry 2014年第17期5卷 1214-1227页

作者： Nastaran Manouchehri Thi Minh Loi Nguyen Stéphane Besancon Lan anh le Alain Bermond AgroParisTech UMR 1145 Paris France AgroParisTech Laboratoire de Chimie Analytique Paris France Laboratory of Analytical Science and Technology Institute of Chemistry Hanoi Vietnam

Modified BCR sequential extraction, single equilibrium-based EDTA extraction and kinetic fractionation were used for estimating the Pb and Cd availability in a series of soil samples from 3 sites located in urban areas of Hanoi (Vietnam). These schemes were compared to identify a simple, rapid and cheap protocol for routine estimation of Pb and Cd remobilizable fraction and the related potential risk. The comparison of these three approaches revealed their convergence in terms of mobility patterns observed for Pb and Cd. Cd was characterized by higher extractibality and mobility whatever the approach. Pb was distinguished of Cd by its high association to Feoxides, lower extractability, lower rate of desorption and then lower mobility. For this environmental scenario, EDTA single scheme at equilibrium could be suggested as the best suited and a simple protocol for determination of the labile pool of Cd and Pb. The pseudo-total concentrations of Pb and Cd are actually below the Vietnamese standard level, contrary to the results obtained by other authors for agricultural soils at other urban sites of Hanoi.

关键词： Trace Metal Soil Sequential Extraction Kinetic Fractionation

Use of Poly-Lactic Acid (PLA) to Enhance Properties of Paper Based on Recycled Pulp

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Advances in Chemical Engineering and Science 2014年第3期4卷 347-360页

作者： Klaus Doelle anh T. le Thomas E. Amidon Biljana M. Bujanovic Department of Paper and Bioprocess Engineering State University of New York College of Environmental Science and Forestry Syracuse USA

Nowadays, recycled paper is broadly used due to environmental reasons. Furthermore, the addition of starch as a dry strength additive improves the properties of recycled paper. Poly-Lactic Acid (PLA), a product from bio-refinery process, has recently been shown to act as a promising strength additive that could be used in combination with starch to further improve the strength of paper. In this study, the use of PLA of three molecular weights (MW) in combination with four different starches was investigated. Three recycled pulps from different origins, with the kappa number of 27.9 to 66 were used. Paper handsheets were made, and selected paper properties were tested. The results indicate that handsheets properties were influenced by the MW of PLAs, the type of starch used, and the lignin content of the pulp. The paper handsheets made from lignin-rich pulp (pulp A, kappa number 66), combined with 0.1% medium MW PLA (PLA_1) and 0.9% cationic starch containing 0.43% N gave the highest improvement for tensile strength, wet tensile strength, air and water resistance. This result verifies that a higher kappa number pulp has better attraction to the hydrophobic PLA. Moreover, the higher charge cationic starch led to higher tensile strength due to the increase of affinity to the anionic fiber surface. Interestingly, results show that amphoteric starch is a promising substitute for high cationic charge starch when combined with the medium MW PLA to improve tensile strength of paper. This study demonstrated that a starch-PLA blend represents a promising approach in improving properties of recycled paper.

关键词： Poly-Lactic Acid (PLA) Recycled Pulp (OCC) Starch Paper Properties Paper Handsheets

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微电网电压不平衡的分层补偿控制策略

哈尔滨工业大学学报 2016年第3期48卷 46-52页

作者：黎金英艾欣邓玉辉新能源电力系统国家重点实验室(华北电力大学) 北京102206 绥和工业学院电气与电子工程学院越南绥和56000

微电网是消纳分布式电源的有效手段之一,然而也带来了其自身的电压控制的难题,特别是公共连接点处的三相电压不平衡问题比较突出,为此提出一种微电网公共连接点电压双极补偿控制方法,上层控制发送与电压的正序和负序分量有关的控制信号... 详细信息

微电网是消纳分布式电源的有效手段之一,然而也带来了其自身的电压控制的难题,特别是公共连接点处的三相电压不平衡问题比较突出,为此提出一种微电网公共连接点电压双极补偿控制方法,上层控制发送与电压的正序和负序分量有关的控制信号,采用双电流环的控制器可得到电流给定值;下层控制通过双电流环控制器实施.针对PCC点三相电压不平衡的问题,应用dq旋转坐标分解原理,提出一种基于改进解耦的双同步坐标系锁相环(IDDSRF-PLL)的控制方法,能够实现正负序分量的独立控制,并通过控制给定模型的正负序电流和电压不平衡补偿控制器得到三相平衡电压,使得公共连接点母线电压的二倍频波动部分为零,从而实现了对三相电压不平衡的补偿控制.利用MATLAB/Simulink对微电网接入电网进行建模仿真,结果表明,分层控制方法能够较好的实现对微电网的电压控制.

关键词：微电网三相电压不平衡锁相环 PQ控制分层控制