检索结果-南通市图书馆

International Soil and Water Conservation Research 2019年第4期7卷 362-375页

作者： Chuong Van Huynh Catharien Terwisscha van Scheltinga Ty Huu Pham Non Quoc Duong Phuong Thi Tran Linh Hoang Khanh nguyen Tung Gia Pham ngoc bich nguyen Jos Timmerman Hue University Viet Nam Climate Change and Adaptive Land and Water Management Group Wageningen Environmental ResearchNetherlands University of Agriculture and Forestry Hue UniversityViet Nam

In recent years,water for agricultural production gradually became a significant challenge in the context of climate change in *** solutions are required,which consider the use of resources for both human needs and ecology,and that account for the equitable distribution and the livelihood of the farmers now and in the *** particular,the farmers in the province of Quang Nam faring water shortage in the cultivation of paddy in the summer-autumn *** arise regarding the sharing of the water between the farmers,the drinking water company and the hydropower *** the context of climate change,the water shortage is expected to increase in the *** article presents the results of participatory action research (PAR) approach to develop a local level mechanism for water sharing,in which stakeholders actively *** sharing mechanism was developed,envisioning a sustainable solution for inclusive water *** mechanism was successfully implemented in two cases,one at commune level (Tho stream) and one at the district level (Mo stream).The participatory approach proved to be successful in setting up a broadly acceptable mechanism that will need to be further incorporated in the institutional set-up.

关键词： Adaptation Agriculture Climate change Governance Rice production Water sharing

Spectral properties of the surface reflectance of the northern polar region of Mercury

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2020年第3期20卷 92-107页

作者： nguyen bich ngoc Nicolas Bott Pham ngoc Diep Department of Astrophysics Vietnam National Space CenterVietnam Academy of Science and Technology18 Hoang Quoc VietCau GiayHanoiVietnam Laboratoire d'Etudes Spatiales et d' Instrumentation en Astrophysique l'Observatoire de Paris5 place Jules Janssen 92195 MeudonFrance

We analyze MESSENGER reflectance measurements covering the northern polar region of Mercury,the least studied region of the northern mercurian *** use observations from the Mercury Dual Imaging System Wide-Angle Camera(MDIS/WAC)and the Mercury Atmospheric and Surface Composition Spectrometer(MASCS/VIRS)to study the spectral dependence of the surface *** results obtained from the observations made by both instruments are remarkably *** find that a second degree polynomial description of the measured reflectance spectra gives very good fits to the data and that the information that they carry can best be characterized by two parameters,the mean reflectance and the mean relative spectral slope,averaged over the explored range of *** properties of the four main types of terrains known to form Mercury’s regolith in the northern region,smooth plains(SPs),heavily cratered terrain(HCT),fresh ejecta/materials and red pitted ground(RPG),are examined in terms of these two *** results are compared,and found consistent with those obtained by earlier studies in spite of difficulties met in obtaining accurate reflectance measurements under the large incidence angle condition characteristic of polar *** results will help with the preparation of the BepiColombo mission and with supporting its observational strategy.

关键词： planets and satellites terrestrial planets-planets and satellites surfaces-techniques spectroscopic

Contributions of Rotation,Expansion and Line Broadening to the Morphology and Kinematics of the Inner CSE of Oxygen-rich AGB Star R Hya

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2023年第1期23卷 40-47页

作者： Pham Tuyet Nhung Do Thi Hoai Pierre Darriulat Pham ngoc Diep nguyen bich ngoc Tran Thi Thai Pham Tuan-Anh Department of Astrophysics Vietnam National Space CenterVietnam Academy of Science and Technology18Hoang Quoc VietNghia DoCau GiayHa NoiVietnam

We use archival ALMA observations of the CO(2-1)and SiO(5-4)molecular line emissions of AGB star R Hya to illustrate the relative contributions of rotation,expansion and line broadening to the morphology and kinematics of the circumstellar envelope(CSE)within some~70 au(~0."5)from the centre of the *** give evidence for rotation and important line broadening to dominate the inner region,within~14 au(~100 mas)from the centre of the *** former is about an axis that projects a few degrees west of north and has a projected rotation velocity of a few km s^(-1).The latter occurs within some 7-14 au(50-100 mas)from the centre of the star,with the line width reaching two to three times its value outside this *** suggest that it is caused by shocks induced by stellar pulsations and convective cell *** show the importance of properly accounting for the observed line broadening when discussing rotation and evaluating the radial dependence of the rotation velocity.

关键词： stars AGB and post-AGB-(stars:)circumstellar matter-radio lines

Electronic Band Structure of Carbon Nanotubes with Kekule Structure

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2013年第9期30卷 97-100页

作者： nguyen ngoc Hieu Le Cong Nhan Center of Research and Development Duy Tan UniversityK7/25 Quang TrungDa NangViet Nam Department of Environmental Science Saigon University273 An Duong VuongHo Chi Minh cityViet Nam

Electronic band structure of carbon nanotubes with the Kekule structure is studied by the tight-binding *** give a complete geometrical approach to structural properties of carbon nanotubes with bond alternation,including chiral and achiral *** the Kekule is introduced,all carbon nanotubes become semiconducting with a small band gap at the Fermi *** band gap of the carbon nanotubes depends only on the difference between C–C bond lengths or the resonance integrals.

关键词： carbon structure Fermi

ON BOUNDEDNESS PROPERTY OF SINGULAR INTEGRAL OPERATORS ASSOCIATED TO A SCHRODINGER OPERATOR IN A GENERALIZED MORREY SPACE AND APPLICATIONS

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2020年第5期40卷 1171-1184页

作者： Xuan Truong LE Thanh Nhan nguyen ngoc Trong nguyen Division of Computational Mathematics and Engineering Institute for Computational ScienceTon Due Thang UniversityHo Chi Minh CityVietnam Faculty of Mathematics and Statistics Ton Due Thang UniversityHo Chi Minh CityVietnam Department of Mathematics Ho Chi Minh City University of EducationHo Chi Minh CityVietnam Department of Primary Education Ho Chi Minh City University of EducationHo Chi Minh CityVietnam

In this paper,we provide the boundedness property of the Riesz transforms associated to the Schrodinger operator■=-Δ+V in a new weighted Morrey space which is the generalized version of many previous Morrey type *** additional potential V considered in this paper is a non-negative function satisfying the suitable reverse Holder's *** results are new and general in many cases of *** an application of the boundedness property of these singular integral operators,we obtain some regularity results of solutions to Schrodinger equations in the new Morrey space.

关键词： weighted Morrey spaces Schodinger operator riesz transforms Regularity estima tes

Truly optimal semi-active damping to control free vibration of a single degree of freedom system

在线全文

学校读者我要写书评

暂无评论

Theoretical & Applied Mechanics Letters 2024年第2期14卷 142-145页

作者： Viet Duc La ngoc Tuan nguyen Institute of Mechanics Vietnam Academy of Science and TechnologyHanoi 10000Vietnam Graduate University of Science and Technology Vietnam Academy of Science and TechnologyHanoi 10000Vietnam

This paper studies a single degree of freedom system under free vibration and controlled by a general semiactive damping.A general integral of squared error is considered as the performance index.A one-time switching damping controller is proposed and *** pontryagin maximum principle is used to prove that no other form of semi-active damping can provide the better performance than the proposed one-time switching damping.

关键词： Analytical optimization Quadratic integral Lyapunov equation Pontryagin maximum principle

ON A NONLINEAR VOLTERRA-HAMMERSTEIN INTEGRAL EQUATION IN TWO VARIABLES

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2013年第2期33卷 484-494页

作者： Le Thi Phuong ngoc nguyen Thanh Long Nhatrang Educational College 01 Nguyen Chanh Str.Nhatrang CityVietnam Department of Mathematics and Computer Science University of Natural ScienceVietnam National University Ho Chi Minh City227 Nguyen Van Cu Str.Dist. 5Ho Chi Minh CityVietnam

Using a fixed point theorem of Krasnosel＇skii type, this article proves the exis- tence of asymptotically stable solutions for a Volterra-Hammerstein integral equation in two variables.

关键词： Volterra-Hamnmrstein integral equation in two variables the fixed point theo-rem of Krasnosel'skii type contraction mapping completely continuous asymp-totically stable solution

Examination of n-T_(9) conditions required by N=50,82,126 waiting points in r-process

在线全文

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2021年第10期73卷 147-157页

作者： nguyen Duy Ly nguyen ngoc Duy nguyen Kim Uyen Vinh N T Pham Faculty of Fundamental Sciences Vanlang UniversityHo Chi Minh City 700000Vietnam Department of Physics Sungkyunkwan UniversitySuwon 16419Republic of Korea Department of Physics Ho Chi Minh City University of EducationHo Chi Minh City 700000Vietnam

We examined the conditions of neutron density(n) and temperature(T9) required for the N = 50, 82,and 126 isotopes to be waiting points(WP) in the r-process. The nuclear mass based on experimental data presented in the AME2020 database(AME and AME ± Δ) and that predicted using FRDM,WS4, DZ10, and KTUY models were employed in our estimations. We found that the conditions required by the N = 50 WP significantly overlap with those required by the N = 82 ones, except for the WS4 model. In addition, the upper(or lower) bounds of the n-T9 conditions based on the models are different from each other due to the deviations in the two-neutron separation *** standard deviations in the nuclear mass of 108 isotopes in the three N = 50, 82, and 126 groups are about rms = 0.192 and 0.434 Me V for the pairs of KTUY-AME and WS4-KTUY models,respectively. We found that these mass uncertainties result in a large discrepancy in the nn-T_(9) conditions, leading to significant differences in the conditions for simultaneously appearing all the three peaks in the r-process abundance. The newly updated FRDM and WS4 calculations can give the overall conditions for the appearance of all the peaks but vice versa for their old versions in a previous study. The change in the final r-process isotopic abundance due to the mass uncertainty is from a few factors to three orders of magnitude. Therefore, accurate nuclear masses of the r-process key nuclei, especially for 76 Fe,81Cu,127Rh,132Cd,192Dy, and 197Tm, are highly recommended to be measured in radioactive-ion beam facilities for a better understanding of the r-process evolution.

关键词： neutron capture r-process nuclear mass isotopic abundance precise mass measurement

Nitrate removal and extracellular polymeric substances of autohydrogenotrophic bacteria under various pH and hydrogen flow rates

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2018年第1期30卷 50-57页

作者： Tran-ngoc-Phu nguyen Pei-Chung Chen Chihpin Huang Institute of Enuironmental Engineering National Chiao Tung UniuersityHsinchu 300Chinese Taipei

In recent years there has been an increasing interest in the use of autohydrogenotrophic bacteria to treat nitrate from wastewater. However, our knowledge about the characteristics of extracellular polymeric substances（EPS） releasing by these activities is not yet very advanced. This study aimed to investigate the change in EPS compositions under various p H values and hydrogen flow rates, taking into consideration nitrogen removal. Results showed that p H 7.5 and a hydrogen flow rate of 90 m L/min were the optimal operating conditions, resulting in 100% nitrogen removal after 6 hr of operation. Soluble and bound polysaccharides decreased, while bound proteins increased with increasing p H. Polysaccharides increased with increasing hydrogen flow rate. No significant change of bound proteins was observed at various hydrogen flow rates.

关键词： Autohydrogenotrophic bacteria Nitrate removal Extracellular polymeric substances Polysaccharides Proteins

Optimizing Bidders Selection of Multi-Round Procurement Problem in Software Project Management Using Parallel Max-Min Ant System Algorithm

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2021年第1期66卷 993-1010页

作者： Dac-Nhuong Le Gia Nhu nguyen arish Garg Quyet-Thang Huynh Trinh ngoc Bao nguyen ngoc Tuan Institute of Research and Development Duy Tan UniversityDa Nang550000Vietnam Faculty of Information Technology Duy Tan UniversityDa Nang550000Vietnam Faculty of Information Technology Haiphong UniversityHaiphong180000Vietnam Graduate School Duy Tan UniversityDa Nang550000Vietnam School of Mathematics Thapar Institute of Engineering and TechnologyPatiala147004India Hanoi University of Science and Technology Hanoi100000Vietnam Hanoi University Hanoi100000Vietnam Department of ICT Ministry of Education and TrainingHanoi100000Vietnam

This paper presents a Game-theoretic optimization via Parallel Min-Max Ant System(PMMAS)algorithm is used in practice to determine the Nash equilibrium value to resolve the confusion in choosing appropriate bidders of multi-round procurement problem in software project *** this end,we introduce an approach that proposes:(i)A Game-theoretic model of multiround procurement problem(ii)A Nash equilibrium strategy corresponds to multi-round strategy bid(iii)An application of PSO for the determination of global Nash *** balance point in Nash Equilibrium can help to maintain a sustainable structure not only in terms of project management but also in terms of future *** an alternative of procuring entities subjectively,a methodology to support decision making has been studied using Nash equilibrium to create a balance point on benefit in procurement where buyers and suppliers need multiple rounds of *** goal focus on the balance point in Nash Equilibrium to optimizing bidder selection in multi-round procurement which is the most beneficial for both investors and selected *** PMMAS algorithm is implemented based on MPI(message passing interface)to find the approximate optimal solution for the question of how to choose bidders and ensure a path for a win-win relationship of all participants in the procurement *** also evaluate the speedup ratio and parallel efficiency between our algorithm and other proposed *** the experiment results,the high feasibility and effectiveness of the PMMAS algorithm are verified.

关键词： Parallel min-max ant system multi-objective multi-round procurement software project management project conflicts Nash equilibrium game theory MPI