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Some Mean Convergence Theorems for the Maximum of normed Double Sums of Banach Space Valued Random Elements

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1727-1740页

作者： Andrew ROSALSKY Le Van THanh nguy.n Thi thuy Department of Statistics University of FloridaGainesvilleFL 32611-8545USA Department of Mathematics Vinh UniversityVinhNghe AnViet Nam High School for Gifted Students Vinh UniversityVinhNghe AnViet Nam

In this correspondence,we establish mean convergence theorems for the maximum of normed double sums of Banach space valued random *** of the results pertain to random elements which are *** expand and improve a number of particular cases in the literature on mean convergence of random elements in Banach *** of the main contributions of the paper is to simplify and improve a recent result of Li,Presnell,and Rosalsky[Journal of Mathematical Inequalities,16,117–126(2022)].A new maximal inequality for double sums of M-dependent random elements is proved which may be of independent *** sharpness of the results is illustrated by four examples.

关键词： Double sum mean convergence Rademacher type p Banach space Banach space valued random element M-dependent random elements

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FDI对越南企业发展的影响研究

FDI对越南企业发展的影响研究

作者：阮维英（nguy(?)n Duy anh）东华大学

学位级别：硕士

国际贸易与外商直接投资是两种重要的国际经济关系,传统上,人们将国际贸易与外商直接投资视作两种不同的经济现象,并分别加以研究。但是随着经济全球的日益深入,二者之间联系越来越密切,表现出相互促进和相互补充的交叉发展特征。20世... 详细信息

国际贸易与外商直接投资是两种重要的国际经济关系,传统上,人们将国际贸易与外商直接投资视作两种不同的经济现象,并分别加以研究。但是随着经济全球的日益深入,二者之间联系越来越密切,表现出相互促进和相互补充的交叉发展特征。20世纪80年代中期,越南实施“改革开放“的新政策,选择了积极融入世界经济体系和广泛与经济全球化的发展战略。25年来,大力吸引外国直接投资成为了越南开展对外经贸合作的重要部分。随着越南改革开放的不断深化,大量外资涌入越南。FDI的流入对越南的经济发展产生了广泛而深刻的影响,尤其08年金融危机爆发后,FDI的变已经成为影响越南经济波动的重要外部因素。FDI通过改变一国的信贷约束和资产价格影响企业的投资和生产决策行为,并通过金融加速器效应,引进经济的大幅波动。作为一名在华越南留学生,在企业管理专业研究生求学期间开始关注FDI对越南企业发展的影响问题,并将作为学位论文展开研究,形成论文.主要研究两个方面：研究越南的FDI通过对越南企业进出口的影响和FDI对于越南国内企业管理运营的影响。并且本人得出总体结论、第一：FDI在越南体现了显著的贸易创造效应。相比之下,越南内资企业的对外贸易总量则处于停滞不前的状态。总之FDI通过它的资本投入、技术投入、提升了越南贸易产品的国际竞争力,迅速扩展了国际市场空间。第二：外资给合资企业带来的新技术并没有对提高越南的国际竞争力做出最大贡献,越南利用外资来获得先进技术和由先进技术确定的竞争力提高的目的并没有完全实现。

关键词： [越南] [外商直接投资] [对外贸易] [企业管理]

Preliminary Study of Photometric Redshifts Based on the Wide Field Survey Telescope

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Research in Astronomy and Astrophysics 2023年第12期23卷 138-152页

作者： Yu Liu Xiao-Zhi Lin Yong-Quan Xue Huynh anh n.Le CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China

The Wide Field Survey Telescope(WFST)is a dedicated time-domain multi-band(u,g,r,i,and z)photometric survey facility under *** this paper,we present a preliminary study that assesses the quality of photometric redshifts based on WFST by utilizing mock observations derived with the galaxy catalog in the COSMOS/UltraVISTA *** apply the template fitting technique to estimate photometric redshifts by using the ZEBRA photometric-redshift code and adopting a modified set of adaptive *** evaluate the bias(median relative offset between the output photometric redshifts and input redshifts),normalized median absolute deviation(σ_(nMAD))and outlier fraction(f_(outlier))of photometric redshifts in two typical WFST observational cases,the single 30 s exposure observations(hereafter shallow mode)and co-added 50 minutes exposure observations(hereafter deep mode).We find bias≲0.006,σ_(nMAD)≲0.03,and f_(outlier)≲5%in the shallow mode and bias≈0.005,σ_(nMAD)≈0.06,and f_(outlier)≈17%–27%in the deep mode,respectively,under various lunar *** the WFST mock observational data with that from the upcoming CSST and Euclid surveys,we demonstrate that the zphot results can be significantly improved,with f_(outlier)≈1%andσ_(nMAD)≈0.02.

关键词： galaxies distances and redshifts-galaxies high-redshift-galaxies photometry

Xanthine oxidase inhibitors from Archidendron clypearia(Jack.) I.C. nielsen: Results from systematic screening of Vietnamese medicinal plants

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Asian Pacific Journal of Tropical Medicine 2017年第6期10卷 619-626页

作者： nguy.n thuy Duong Pham Duc Vinh Phuong Thien Thuong nguy.n Thi Hoai Le nguy.n Thanh Tran The Bach nguy.n Hai nam nguy.n Hoang anh Department of Pharmacology Hanoi University of Pharmacy Department of Pharmaceutical Analysis and Standardization National Institute of Medicinal Materials Department of Pharmacognosy Hue University of Medicine and Pharmacy Institute of Marine Biochemistry Vietnam Academy of Science and Technology Institute of Ecology and Biological Resources Vietnam Academy of Science and Technology Department of Medicinal Chemistry Hanoi University of Pharmacy

Objective: To screen Vietnamese medicinal plants for xanthine oxidase(XO) inhibitory activity and to isolate XO inhibitor(s) from the most active plant. Methods: The plants materials were extracted by methanol. The active plant materials were fractionated using different organic solvents, including n-hexane, ethyl acetate, and n-butanol. Bioassay-guided fractionation and column chromatography were used to isolate compounds. The compounds structures were elucidated by analysis of spectroscopic data, including IR, MS, and nMR. Results: Three hundreds and eleven methanol extracts(CME) belonging to 301 Vietnamese herbs were screened for XO inhibitory activity. Among these plants, 57 extracts displayed XO inhibitory activity at 100 μg/m L with inhibition rates of over 50%. The extracts of Archidendron clypearia, Smilax poilanei, Linociera ramiflora and Passiflora foetida exhibited the greatest potency with IC_(50) values below 30 μg/m L. Chemical study performed on the extract of Archidendron clypearia resulted in the isolation of six compounds, including 1-octacosanol, docosenoic acid, daucosterol, methyl gallate, quercitrin and(-)-7-O-galloyltricetiflavan. The compound(-)-7-O-galloyltricetiflavan showed the most potent XO inhibitory activity with an IC_(50) value of 25.5 μmol/L. Conclusions: From this investigation, four Vietnamese medicinal plants were identified to have XO inhibitory effects with IC_(50) values of the methanol extracts below 30 μg/m L. Compound(-)-7-O-galloyltricetiflavan was identified as an XO inhibitor from Archidendron clypearia with IC_(50) value of 25.5 μmol/L.

关键词： Xanthine oxidase Inhibitor Medicinal plants Vietnam

AGn Lifetimes in UV-selected Galaxies: A Clue to Supermassive Black Hole-galaxy Coevolution

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Research in Astronomy and Astrophysics 2022年第1期22卷 104-113页

作者： Xiaozhi Lin Yongquan Xue Guanwen Fang Lulu Fan Huynh anh n Le Ashraf Ayubinia CAS Key Laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China School of Mathematics and Physics Anqing Normal UniversityAnqing 246133China Shandong Provincial Key Lab of Optical Astronomy and Solar-Terrestrial Environment Institute of Space ScienceShandong UniversityWeihai264209China

The coevolution between supermassive black holes(SMBHs) and their host galaxies has been proposed for more than a decade,albeit with little direct evidence about black hole accretion activities regulating galaxy star formation at z> *** this paper,we study the lifetimes of X-ray active galactic nuclei(AGns) in UV-selected red sequence(RS),blue cloud(BC) and green valley(GV) galaxies,finding that AGn accretion activities are most prominent in GV galaxies at z ~1.5-2,compared with RS and BC *** also compare AGn accretion timescales with typical color transition timescales of UV-selected *** find that the lifetime of GV galaxies at z~1.5-2 is very close to the typical timescale when the AGns residing in them stay in the high-accretion-rate mode at these redshifts;for BC galaxies,the consistency between the color transition timescale and the black hole strong accretion lifetime is more likely to happen at lower redshifts(z nario where AGn accretion activities govern UV color transitions of host galaxies,making galaxies and their central SMBHs coevolve with each other.

关键词： galaxies:active galaxies:formation galaxies:evolution galaxies:high-redshift galaxies:nuclei (galaxies:)quasars:supermassive black holes galaxies:star formation galaxies:statistics

Study of vertically ascending flight of a hawkmoth model

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Acta Mechanica Sinica 2020年第5期36卷 1031-1045,I0002页

作者： anh Tuan nguy.n Vu Dan Thanh Le The Hung Tran V.n.Due Van Binh Phung Faculty of Aerospace Engineering Le Quy Don Technical UniversityHanoiVietnam Institute of Theoretical and Applied Research.Duy Tan University HanoiVietnam Division of Construction Computation Institute for Computational ScienceTon Due Thang UniversityHo Chi Minh CityVietnam Faculty of Civil Engineering Ton Due Thang UniversityHo Chi Minh CityVietnam

This paper provides insight into the wing kinematics,the power requirement and the dynamic stability characteristics of a hawkmoth model in vertically ascending *** wing kinematics of the hawkmoth model is obtained based on the minimum required power *** optimization process is conducted using genetic and simplex algorithms that are coupled with an artificial neural network to rapidly predict the aerodynamic force and required *** training data for the neural network are generated from an unsteady vortex-lattice *** to hover,the results in this study show the larger flapping frequency and the smaller rotation amplitude of the hawkmoth wing kinematics in ascending ***,more power is required when the ascending speed *** conducting a dynamic modal analysis based on a cycle-average approach,the certain effect of the ascending speed on the modal structures of the hawkmoth model was observed.

关键词： Hawkmoth Ascending flapping flight-Genetic algorithm Artificial neural network Flight dynamic stability

On the Laws of Large numbers for Double Arrays of Independent Random Elements in Banach Spaces

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Acta Mathematica Sinica,English Series 2014年第8期30卷 1353-1364页

作者： Andrew ROSALSKY Le Van THanh nguy.n Thi thuy Department of Statistics University of FloridaGainesville Department of Mathematics Vinh University

For a double array of independent random elements {Vmn,m ≥ 1,n ≥ 1} in a real separable Banach space,conditions are provided under which the weak and strong laws of large numbers for the double sums mi=1 nj=1Vij,m ≥ 1,n ≥ 1 are *** the identically distributed and the nonidentically distributed cases are *** the main theorems,no assumptions are made concerning the geometry of the underlying Banach *** theorems are applied to obtain Kolmogorov,Brunk–Chung,and Marcinkiewicz–Zygmund type strong laws of large numbers for double sums in Rademacher type p（1 ≤ p ≤ 2） Banach spaces.

关键词： Real separable Banach space double array of independent random elements strong and weak laws of large numbers almost sure convergence convergence in probability Rademacher type p Banach space

Activated carbon derived from rice husk by naOH activation and its application in supercapacitor

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Progress in natural Science:Materials International 2014年第3期24卷 191-198页

作者： Khu Le Van Thu thuy Luong Thi Physical Chemistry Department Hanoi University of Education

Four activated carbon(AC) samples prepared from rice husk under different activation temperatures have been characterized by n2adsorption–desorption isotherms, thermogravimetric analysis(TGA–DTA), Fourier transform infrared spectroscopy(FTIR) and scanning electron microscopy(SEM). The specific surface area of AC sample reached 2681 m2 g 1under activation temperature of 800 1C. The AC samples were then tested as electrode material; the specific capacitance of the as-prepared activated carbon electrode was found to be 172.3 F g 1using cyclic voltammetry at a scan rate of 5 mV s 1and 198.4 F g 1at current density 1000 mA g 1in the charge/discharge mode.& 2014 Chinese Materials Research Society. Production and hosting by Elsevier B.V. All rights reserved.

关键词： Rice husk Activated carbon Supercapacitor Surface area Micropore

A concise review on surface and structural modification of porous zeolite scaffold for enhanced hydrogen storage

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Chinese Journal of Chemical Engineering 2024年第6期70卷 33-53页

作者： B.A.Abdulkadir R.S.R.Mohd Zaki A.T.Abd Wahab S.n.Miskan anh-Tam nguy.n Dai-Viet n.Vo H.D.Setiabudi Centre for Research in Advanced Fluid&Processes Universiti Malaysia Pahang Al-Sultan AbdullahLebuh Persiaran Tun Khalil YaakobGambangPahang 26300Malaysia Faculty of Chemical&Process Engineering Technology Universiti Malaysia Pahang Al-Sultan AbdullahLebuh Persiaran Tun Khalil YaakobGambangPahang 26300Malaysia Center of Excellence for Green Energy and Environmental nanomaterials(CE@GrEEn) Nguyen Tat Thanh University300A Nguyen Tat ThanhDistrict 4Ho Chi Minh City 755414Viet Nam

Investigating zeolites as hydrogen storage scaffolds is imperative due to their porous nature and favorable physicochemical ***,the storage capacity of the unmodified zeolites has been rather unsatisfactory(0.224%-1.082%(mass))compared to its modified ***,the contemporary focus on enhancing hydrogen storage capacities has led to significant attention towards the utilization of modified zeolites,with studies exploring surface modifications through physical and chemical treatments,as well as the integration of various active *** enhanced hydrogen storage properties of zeolites are attributed to the presence of aluminosilicates from alkaline and alkaline-earth metals,resulting in increased storage capacity through interactions with the charge density of these ***,there is a great demand to critically review their role such as well-defined topology,pore structure,good thermal stability,and tunable hydrophilicity in enhanced hydrogen *** article aimed to critically review the recent research findings based on modified zeolite performance for enhanced hydrogen *** of the factors affecting the hydrogen storage capacities of zeolites that can affect the rate of reaction and the stability of the adsorbent,like pressure,structure,and morphology were studied,and ***,future perspectives,recommendations,and directions for modified zeolites were discussed.

关键词： Zeolites Hydrogen storage Surface modification Adsorption Active metal