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上位效应对遗传算法可靠性的影响（英文）

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2019年第2期20卷 109-116页

作者： Sajad JAFARI Tomasz KAPITANIAK Karthikeyan RAJAGOPAL viet-Thanh PHAM Fawaz E.ALSAADI Biomedical Engineering Department Amirkabir University of Technology Division of Dynamics Lodz University of Technology Center for Nonlinear Dynamics Defence University6020 BishoftuEthiopia Modeling Evolutionary Algorithms Simulation and Artificial Intelligence Faculty of Electrical&Electronics EngineeringTon Duc Thang University Department of Information Technology Faculty of Computing and ITKing Abdulaziz University

目的:探讨遗传算法的局限性和实用性,并分析基于相互作用产生的上位效应对遗传算法可靠性的影响。创新点:1.指出遗传算法缺陷的根源;2.基于测试样本函数定义目标函数,以判断遗传算法的适用性。方法:1.基于非上位效应函数(表1)和上位效... 详细信息

目的:探讨遗传算法的局限性和实用性,并分析基于相互作用产生的上位效应对遗传算法可靠性的影响。创新点:1.指出遗传算法缺陷的根源;2.基于测试样本函数定义目标函数,以判断遗传算法的适用性。方法:1.基于非上位效应函数(表1)和上位效应函数(表2),以及非上位效应函数F4和上位效应函数F6的结构图来验证遗传算法可靠性;2.通过计算样本函数(公式(1))和遗传算法流程(图3)表达遗传算法的工作原理。3.利用克洛弗函数(公式(2))和计算不同结构角下的函数分布(图4),进一步判断匹配度(表3)和计算效率(表4);定义新的目标函数(公式(9))和一组新的变量(公式(10))来实现变量相关性解离。结论:1.对当前遗传算法存在的不足给出了独到见解,并认为正定性的假设并非可以保证遗传算法实际的有效性和优化性。2.定义成本代价函数用以判断遗传算法可靠性,并分别考虑上位性和非上位性效应两种情形。当成本代价函数在非上位性效应下时,遗传算法是有效的;否则,可以把N维函数降级为N个一维函数,从而采用更简单的算法来判断。基于一些通用的基准,进一步设计三类样本函数来证实以上判断,且这些样本函数适合于上位性效应情形和非上位效应情形。3.遗传算法的瓶颈在于主算子和相干匹配性;可以通过破坏某些结构来实现变量关系的解离,从而抑制相干匹配性对遗传算法的影响。希望相关读者在处理实际优化问题时能验证作者关于上位效应的定性结论,并给出更可靠的方法来表征这种效应。

关键词：上位性效应遗传算法相干匹配性叠加性优化成本代价函数

Genetic diversity in two threatened species in vietnam:Taxus chinensis and Taxus wallichiana

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Journal of Forestry Research 2017年第2期28卷 265-272页

作者： Dinh Duy Vu Thi Tuyet Xuan Bui Minh Tam Nguyen Dinh Giap Vu Minh duc Nguyen Van Thang Bui Xiaohua Huang Yi Zhang College of Forestry Northwest A&F UniversityYangling 712100ShaanxiPeople's Republic of China vietnam National Museum of Nature Vietnam Academy of Science and Technology(VAST)18 Hoang Quoc VietCau GiayHanoiVietnam Institute of Ecology and Biological Resource(VAST) 18 Hoang Quoc VietCau GiayHanoiVietnam Institute of Natural Products Chemistry(VAST) 18 Hoang Quoc VietCau GiayHanoiVietnam Institute of Forest Biotechnology Vietnam Forestry UniversityXuan MaiChuong MyHanoiVietnam

Taxus chinensis and T. wallichiana in have been threatened in their distribution areas in recent decades because of their over-exploitation and reduction and destruction of native habitats. Determining the genetic diversity in populations of the two species will provide guidelines for their protection and preservation. Two hundred and fifteen trees from six populations of T. chinensis and150 sampled trees of T. wallichiana were sampled. Six microsatellite primer pairs selected from 16 primer pairs were used to investigate genetic variation at the population and species levels. Five yielded polymorphic alleles, and among the 13 putative alleles amplified, 11 were polymorphic（accounting for 76.33 %）.Shannon＇s information index（I） and percentage of polymorphic bands（PPB）（I = 0.202 and PPB = 67.22 % for T. chinensis; I = 0.217 and PPB = 65.03 % for T. wallichiana）. Both species had low levels of genetic diversity（mean Ho= 0.107, He= 0.121 for T. chinensis; Ho= 0.095, He= 0.109 for T. wallichiana）. Genetic differentiation among populations was higher（FST= 0.189） for T. chinensis and lower（0.156） for ***, indicating limited gene flow（Nm） among populations for T. chinensis（0.68） and T. wallichiana（0.65）.Variation among individuals of T. chinensis was 63.59 and73.12 % for T. wallichiana. Thus, the threatened status of the two conifers is related to a lack of genetic diversity. All populations are isolated in small forest remnants. An ex situ conservation site should be established with a new population for these species that comprises all the genetic groups for the best chance to improve their fitness under environmental stresses.

关键词： Taxus populations alleles polymorphic microsatellite vietnam primer accounting putative destruction

Application of Bidirectional Power Converters to Overcome Some Disadvantages of SVC Substation

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Journal of Energy and Power Engineering 2012年第12期6卷 2024-2030页

作者： Ngo duc Minh Le Tien Phong Power System Department Electrical Faculty Thai Nguyen University of Technology Thai Nguyen 250000 Viet Nam

When the authors research on the fact that some SVC （static var compensator） substations connected at some buses in power system, they realized that some main functions ensured to operate well. Those are： compensate reactive power following value U＊ according to the requirements of the vietnamese power system dispath center, flit harmonic by passive filter... However, it still has some disadvantages of this substation that need to be overcome： use large number of main devices, generate harmonics by itself, cause a lot of active power losses. Thus, the authors have an idea to solve these problems by applying a bidirectional power converter with having difference circuit structure and PWM （pulse width modulation） controller with SVM （space vector modulation） pulse generated section, so compensative current which is created by inductance element can be reserved, adjust continuos and always has full sinusoidal form, not generating harmonic. The benefit of this new solution is to eliminate the three above fundamental disadvantages. This new model is built based on authors＇ research about BESS （battery energy storage system）. The research results have been verified by simulations in Matlab/Simulink software.

关键词： SVC TSC TCR BDPC reactive power harmonic.

Value of a new stick-type rapid urine test for the diagnosis of Helicobacter pylori infection in the vietnamese population

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World Journal of Gastroenterology 2014年第17期20卷 5087-5091页

作者： duc T Quach Toru Hiyama Fumio Shimamoto Quang D Le Linh X Ho Nhu HT Vu Masaharu Yoshihara Naomi Uemura Department of Endoscopy University Medical CenterHo Chi Minh 70000Vietnam Health Service Center Hiroshima UniversityHigashihiroshima 739-8514Japan Faculty of Human Culture and Science Prefectural University of HiroshimaHiroshima 734-8558Japan Department of Gastroenterology Gia-Dinh People’s HospitalHo Chi Minh 70000Vietnam Department of Gastroenterology and Hepatology National Center for Global Health and MedicineIchikawa 272-8516Japan

AIM: To assess the value of a new test for the diagnosis of Helicobacter pylori (H. pylori) infection, Rapirun®H. pylori Antibody Stick (Rapirun® Stick), in a vietnamese population.

关键词： Helicobacter pylori, Urine test, Rapirun® Stick, vietnamese, Rapid urease test

Assessment of Water Scarcity Levels in the Srepok River Basin

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Open Journal of Modern Hydrology 2024年第4期14卷 231-249页

作者： Le Van Linh Tu Anh Nguyen Nguyen Anh duc Tran Van Tra Nguyen Thanh Long Dang Dinh duc Tran duc Thinh Nguyen Thi Bich Water Resources Institute Ministry of Natural Resources and Environment Ha Noi Viet Nam Center for Environmental Fluid Dynamics VNU University of Science Ha Noi Viet Nam National Centre for Water Resources Planning and Investigation Ministry of Natural Resources and Environment Ha Noi Viet Nam Institute of Geography Viet Nam Academy of Science and Technology Ha Noi Viet Nam

Water scarcity has become a pressing global issue, worsening food security, hindering economic development, compromising environmental quality, and threatening human health and other fundamental societal needs. viet Nam is among the countries severely affected by water scarcity. This study comprehensively assesses the extent and scale of water scarcity in the Srepok River Basin, considering the impacts of water resource allocation, balance, and environmental flows. The areas heavily affected by water scarcity include Ea Hleo, Ea Krong Ana, and several Srepok River branches, with water scarcity periods mainly concentrated in February, March, and April. The influence of climate change has increased the extent and level of water scarcity in the river, affecting an estimated 1.4 million people for at least one month and about 1 million for at least three months. The agricultural sector is significantly affected by water scarcity, with water shortages of 50% according to the baseline scenario and over 60% according to climate change scenarios.

关键词： Water Scarcity Level Water Balance Climate Change RCP 4.5 Srepok River Basin

Research and Design of Inverter Applied in Solar PV Systems Connected to Distribution Grid

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Journal of Electrical Engineering 2019年第1期7卷 28-38页

作者： Nguyen duc Minh Trinh Trong Chuong Bui Van Huy Quach duc Cuong Bui Dinh Thanh Institute of Energy Science Vietnam Academy of Science and Technology18 Hoang Quoc Viet streetCau Giay districtHanoi 10072Vietnam Hanoi University of Industry No. 298Cau Dien streetBac Tu Liem districtHanoi 11915Vietnam Hanoi University of Mining and Geology No.18Pho VienDuc Thang wardBac Tu Liem districtHanoi 11910Vietnam

This paper presents the results of research on the application of inverter in the grid connected solar photovoltaics (PV) system. The main content of the article is to control the three-phase grid connected inverter to meet the requirement of controlling the reactive power to zero at a node of the distribution network while maximizing the active power transmitted to the grid. The control circuits are synthesized on the dq coordinate system and verified on the simulation model by Matlab/Simulink. Both simulation and experimental prototype on 5 kW inverter, being connected to low voltage grid, have been built to show the good results and the practical readiness for implementation.

关键词： SVPWM reactive power solar PV grid connected inverter

Upconversion luminescence of Gd2O3:Er3+and Gd2O3:Er3+/silica nanophosphors fabricated by EDTA combustion method

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Journal of Rare Earths 2019年第11期37卷 1126-1131页

作者： Le Quoc Minh Tran Kim Anh Nguyen Duy Hung Pham Thi Minh Chau Nguyen Thi Quy Hai Ho Van Tuyen Vu Thi Thai Ha Vu duc Tu Wieslaw Strek Institute of Theoretical and Applied Research Duy Tan UniversityDa Nang 55000Viet Nam Advanced Institute for Science and Technology Hanoi University of Science and Technology1 Dai Co VietHai Ba TrungHanoiViet Nam Institute of Materials Science Vietnam Academy of Science and Technology18 Hoang Quoc Viet RoadCau Giay DistrictHanoiViet Nam Institute of Low Temperature and Structure Research Polish Academy of Science 2 OkolnaWroclawPoland

Gd2O3:Er^3+nanophosphors were fabricated by the combustion method in presence of Na2 ethylene diamine tetra acetic acid(EDTA-Na2)as fuel at not high temperature(≤350℃)within a very short time of 5 *** added concentration of Er^3+ions in Gd2O3 matrix was changed from 0.5 mol%to 5.0 mol%.The X-ray diffraction pattern of samples indicates the monoclinic structure of Gd2O3:Er^3+.The morphology and chemical composition analysis of the Gd2O3:Er^3+samples are characterized by a field emission scanning electron microscope(FESEM)and a Fourier-transform infrared spectrometer(FTIR).The photoluminescence(PL),photo luminescence excitation(PLE)and upconversion(UC)at room temperature of the prepared materials with different concentrations of Er^3+were *** PL of Gd2O3:Er^3+nanomaterials are shown in visible at 545,594,623,648,688 nm under excitation at 275 *** emission bands from transitions of Er^3+from 2P3/2 to 4F9/2 are observed,UC luminescent spectra of the Gd2O3:Er^3+/silica nanocomposites under 976 nm excitation show the bands at 548 and 670 *** influence of excitation power at 980 nm for transitions were measured and *** results indicate that the upconversion process of Gd2O3:Er^3+/silica is two photons absorption *** low temperature dependence of UC luminescent intensities of the main bands of Gd2O3:Er^3+was investigated towards development of a nanotemperature sensor in the range of 10-300 K.

关键词： Upconversion luminescence Gd2O3:Er3+ Gd2O3:Er3+/silica Nanophosphors EDTA combustion Rare earths

Genetic diversity and conservation of two threatened dipterocarps(Dipterocarpaceae) in southeast vietnam

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Journal of Forestry Research 2019年第5期30卷 1823-1831页

作者： Dinh-Duy Vu Thi Tuyet-Xuan Bui Minh-duc Nguyen Syed Noor Muhammad Shah Dinh-Giap Vu Yi Zhang Minh-Tam Nguyen Xiao-Hua Huang College of Forestry Northwest A&F UniversityYanglingShaanxi 712100People’s Republic of China vietnam National Museum of Nature Vietnam Academy of Science and Technology(VAST)18 Hoang Quoc VietCau GiayHanoiVietnam Institute of Ecology and Biological Resource Vietnam Academy of Science and Technology(VAST)18 Hoang Quoc VietCau GiayHanoiVietnam Department of Horticulture Faculty of AgricultureGomal UniversityDera Ismail KhanPakistan Institute of Natural Products Chemistry Vietnam Academy of Science and Technology(VAST)18 Hoang Quoc VietCau GiayHanoiVietnam

Two threatened dipterocarp species,Dipterocarpus costatus and Dipterocarpus alatus are well-known endangered species in lowland forests of southeastern vietnam,primarily from habitat loss and over-exploitation of their *** develop conservation strategies for these species,we analyzed 242 samples using nine microsatellite markers to determine the genetic variability within and among five populations of *** and three of ***,representing the natural range of dipterocarps in Southeast *** indicated low levels of genetic variability within populations with an average gene diversity of 0.223 for *** and 0.152 for *** of bottleneck tests indicated a reduction in population size of both species(P>0.05).Genetic differentiation among populations was high(FST=0.347 for *** and 0.274 for ***),indicating limited gene flow(Nm=0.662 for *** and 0.47 for ***)and isolated populations related to geographical *** of molecular variance showed high genetic variation within populations(72.92%for *** and 60.81%for ***)compared to among *** analysis and UPGMA tree also indicated the two optimal genetic clusters related to geographical *** results will provide a platform for the conservation,management and restoration of these species.

关键词： Dipterocarps Genetic conservation Gene diversity SSR primers

Cobalt phosphosulfide nanoparticles encapsulated into heteroatom-doped carbon as bifunctional electrocatalyst for Znair battery

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Advanced Powder Materials

Advanced Powder Materials 2022年第3期1卷 46-53页

作者： Xiaolong Xu Shuo Wang Shiquan Guo Kwan San Hui Jiameng Ma duc Anh Dinh Kwun Nam Hui Hao Wang Lipeng Zhang Guowei Zhou School of Materials Science and Engineering Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China Engineering Faculty of ScienceUniversity of East AngliaNorwichUnited Kingdom Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials EngineeringUniversity of MacaoAvenida da UniversidadeTaipaMacao SARChina NTT Hi-tech Institute Nguyen Tat Thanh UniversityHo Chi Minh City 700000Viet Nam College of Energy State Key Laboratory of Organic Inorganic CompositesBeijing University of Chemical TechnologyBeijing 100029China Key Laboratory of Fine Chemicals in Universities of Shandong Jinan Engineering Laboratory for Multi-scale Functional MaterialsSchool of Chemistry and Chemical EngineeringQilu University of Technology(Shandong Academy of Sciences)Jinan 250353China

CoPS nanoparticles encapsulated with S,P,N tri-doped carbon material(SPNC)were proposed as bifunctional electrocatalyst of oxygen evolution reaction(OER)and oxygen reduction reaction(ORR)derived from zeolitic imidazolate *** functional theory calculations consistently revealed that P element in CoPS@SPNC improves the electrical conductivity and reduces OH^(*)hydrogenation energy barrier on Co sites,thereby facilitating the overall ORR/OER activities.A flexible Zn–air battery with CoPS@SPNC delivered an overpotential of 0.49 V,an energy efficiency above 80%,and a discharge voltage of 1.29 V at 2 mA cm^(-2) for 80 h.

关键词： Bifunctional electrocatalyst Zeolitic imidazolate framework Heteroatom doping Zn-air battery