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Journal of Environmental Protection 2022年第11期13卷 870-880页

作者： Vo Thi Anh Tran Khanh Minh Ha Lan Anh mai dinh kien Vu Hoai Dang Duc Nhan Institute for Nuclear Science and Technology Hanoi Vietnam

The δ18O and δ2H stable isotope techniques for studying properties of groundwater and surface help us to understand more clearly about the distribution and movement of groundwater in the South of Hanoi area. There were 68 water samples from the studying area and analyzed by a Liquid Water Isotope Analyzer (LWIA-24D). The stable isotope values of the groundwater from Pleistocene aquifers were range from -3.21‰ to -9.55‰ δ18O and -35.32‰ to -67.44‰ δ2H;rainwater from -8.18‰ to -4.13‰ δ18O and -61.19‰ to -17.93‰ δ2H;Red river water from -7.51‰ to -5.29‰ δ18O and -51.60‰ to -38.99‰ δ2H. Based on stable isotope characteristics, the results show that there was a relationship between surface water and groundwater in the South of Hanoi city. It is that groundwater recharges for river water in the dry season with 74%, and in the rainfall season groundwater is recharged from river with 87%.

关键词： Stable Isotopes Groundwater Surface Water River Water Precipitation Recharge

Robust Finite-Time Stability and Stabilization of a Class of Fractional-Order Switched Nonlinear Systems

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Journal of Systems Science & Complexity 2019年第6期32卷 1479-1497页

作者： mai Viet Thuan dinh Cong Huong Department for Management of Science and Technology Development Ton Due Thang UniversityHo Chi Minh CityVietnam Faculty of Mathematics and Statistics Ton Due Thang UniversityHo Chi Minh CityVietnam Department of Mathematics Quynhon UniversityBinhdinhVietnam

This paper deals with the problem of finite-time boundedness and fin计e-time stabilization boundedness of frax?tional-order switched nonlinear systems with exogenous *** constructing a simple Lyapunov-like function and using some properties of Caputo derivative,the authors obtain some new sufficient conditions for the problem via linear matrix inequalities,which can be efficiently solved by using existing convex algorithms.A constructive geometric is used to design switching laws amongst the *** obtained results are more general and useful than some existing works,and cover them as special cases,in which only linear fractional-order systems were *** examples are provided to demonstrate the effectiveness of the proposed results.

关键词： Caputo fractional-order derivative finite-time boundedness fractional-order switched systems linear matrix inequalities

New Results on Stability and Stabilization of Delayed Caputo Fractional Order Systems with Convex Polytopic Uncertainties

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Journal of Systems Science & Complexity 2020年第3期33卷 563-583页

作者： dinh Cong Huong mai Viet Thuan DUONG Thi Hong Department for Management of Science and Technology Development Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Mathematics and Statistics Ton Duc Thang UniversityHo Chi Minh CityVietnam Department of Mathematics and Informatics Thainguyen University of SciencesThainguyenVietnam

In this paper,the problems of robust stability and stabilization,for the first time,are studied for delayed fractional-order linear systems with convex polytopic *** authors derive some sufficient conditions for the problems based on linear matrix inequality technique combined with fractional Razumikhin stability *** the results are obtained in terms of linear matrix inequalities that are numerically *** proposed results are quite general and improve those given in the literature since many factors,such as discrete and distributed delays,convex polytopic uncertainties,global stability and stabilizability,are *** examples and simulation results are given to illustrate the effectiveness of the effectiveness of our results.

关键词： Convex polytopic uncertainty delayed caputo fractional-order systems fractional Razumikhin theorem linear matrix inequality robust stability robust stabilization

Simulation of stabilizing process of dielectric nanoparticle in optical trap using counter-propagating pulsed laser beams

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Chinese Optics Letters 2010年第3期8卷 332-334页

作者： Ho Quang Quy mai Van Luu Hoang dinh Hai Donan Zhuang Institute of Applied PhysicsNEWTECHPRO Vietnam Academy of Science and Technology Faculty of PhysicsVinh University Pedagogical College of Nghean Department of PhysicsKing Mingkut's University of Technology Thonburi

The stabilizing process of glass particle in water by optical trap using the pulsed counter-propagating Gaussian beams is investigated. The influence of the optical power and the particle dimension on the rate and tim... 详细信息

关键词： Simulation of stabilizing process of dielectric nanoparticle in optical trap using counter-propagating pulsed laser beams

Some problems on the research and development of the application of methane draining boring technology to prevent hazards in underground coal mines in Vietnam

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Journal of Coal Science & Engineering(China) 2009年第2期15卷 129-133页

作者： NGUYEN Xuan-Thao NGUYEN Tran-Tuan TRAN dinh-kien Institute of Mining Science and Technology University of Mining and Geology

Underground coal mining activities in the Quangninh coal basin (in the North ofVietnam) have been carried out at a depth of-130 m to-150 m,and in the near future thismining depth will become-300 m and-500 *** with the increasing coal output,the quantity of methane and other mine gases emitted from coal beds during mining activitieswill grow bigger and *** to the forecast of the coal mining industry,ifmines go deeper downward,all underground coal mines in the Quangninh basin will beclassified into the mine group with the dangerous level of methane *** gascontrol and management operations with conventional ventilation are less effective andentail high *** of the main solutions is to carry out short,medium and longboreholes for controlling and recovering methane and other mine gases from coal bedsbefore mining *** of drilling activities for methane gas recovery from coalseams with horizontal bore holes at underground coal mines depends on many factors includingthe mine gas draining borehole layout at the roadways,gas content in the coalbeds,technologies for mine gas draining boring activities,and so *** gas existsin the coal beds under the adhesive state with stable physical and chemical *** orderto recover these gases,it is necessary to carry out boreholes and create artificial joints(collecting pits) in coal beds with the impulse method (hydraulic separation method).

关键词： problems methane draining bodng technology Vietnam

Combined transarterial chemoembolization and stereotactic body radiation therapy as a bridge therapy to liver transplant for hepatocellular carcinoma

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Hepatoma Research 2020年第8期6卷 36-45页

作者： Bui Quang Bieu Nguyen dinh Chau Nguyen Xuan kien Le Van Thanh Vu Van Quang Thai Doan Ky Nguyen Tien Thinh mai Hong Bang Department of Radiation Oncology and Radiosurgery Military Central Hospital 108Hanoi 100000Vietnam Department of Hepatobiliary and Pancreatic Surgery Military Central Hospital 108Hanoi 100000Vietnam Department of Gastroenterology and Hepatobiliary Military Central Hospital 108Hanoi 100000Vietnam.

Liver transplant(LT)is the curative treatment for patients with hepatocellular carcinoma(HCC).Bridge therapies are local treatments given to patients on the LT waitlist,to prevent tumor progression and to reduce the dropout *** presentation:We reported a 40-year-old man diagnosed with Barcenola-Clinic Liver Cancer BCLC intermediate stage HCC and Child-Pugh A5 hepatitis B virus cirrhosis who underwent combined bridge therapies to ***,the patient received transarterial chemoembolization(TACE)for two times and showed a partial *** he underwent stereotactic body radiation therapy(SBRT)with a total dose of 45 Gy in 3 *** months later,the tumor size and serum protein induced by Vitamin K absence or antagonists-II,alpha fetoprotein levels decreased *** June 2019 a suitable donor was found and his LT was successfully ***:We propose that a combination of TACE and SBRT was feasible as bridge therapy for HCC patients on the LT waitlist.

关键词： Transarterial chemoembolization stereotactic body radiation therapy bridge therapy hepatocellular carcinoma liver transplant

Evaluation of Weathering Performance of Rosin-Copper Based Treated Wood

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Journal of Renewable Materials 2022年第11期10卷 2765-2780页

作者： Thi Thanh Hien Nguyen Nho Quyet Tran Thi Minh Nguyet Nguyen Hien mai Trinh Xuan Phuong Le Trong kien Nguyen College of Wood Industry and Interior Design Vietnam National University of ForestryHa NoiViet Nam College of Economics and Management Northeast Forestry UniversityHarbinChina

This study aimed to evaluate the effect of natural weathering on some surface characteristics and mechanical properties of Styrax wood treated with mixtures of 1.0%,2.0%,or 4.0%rosin sizing agent and 3%copper *** samples after treatment were exposed to outdoor conditions for one year and changes in color,glossiness,weight loss,compression strength parallel to grain(CSPG),modulus of rupture(MOR),and modulus of elasticity(MOE)were investigated after 6 and 12-month of natural *** results showed that rosin-copper treatment could improve color stability and gloss of samples after *** losses of all rosin-copper treated samples after 12 months of exposure were negligible compared with the untreated control *** addition,rosin-copper treatment enhanced the CSPG compared to untreated controls,but slightly decreased the MOR and MOE of Styrax wood before *** weathering factors induced a reduction for all strength properties,however,the decrease rate for strength properties of rosin-copper treated samples was negligible compared with the untreated control samples after 12-month natural weathering *** FTIR and SEM-EDX confirmed that the use of the rosin-copper formulations to impregnate wood could decrease the hazard of the copper preservative leaching into the environment,while also enhancing more resistance against weathering factors and other biotic factors.

关键词： Rosin-copper weathering color stability CSPG MOR MOE

Research on Subcontractor Risk of EPC Hydropower Project in Vietnam

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World Journal of Engineering and Technology 2019年第1期7卷 54-67页

作者： dinh Bui Sy Hung mai Huu Hai Vu Department of Construction Management Can Loc Committee Ha Tinh Vietnam Department of Hydraulic Engineering and Construction National University of Civil Engineering Hanoi Vietnam

Engineering, procurement and construction (EPC) contracts are becoming the most popular form to undertake construction works on large-scale hydropower projects.?The EPC general contractors in Vietnam have been coped with lots of difficulties during the construction phase of hydropower projects, resulting in significant schedule delays and cost overrun. One of the reasons is poor Subcontractors capacity.?In order to overcome above, the current study attempts?to research on identification and control Subcontractors risks of delay process of EPC hydropower project in Vietnam.?Through summarizing international research achievements of previous researches relating on EPC hydropower projects combining with analysis characteristics of developing construction of EPC hydropower projects in Vietnam, the current study pointed out all kinds of subcontractor risk of delay process of EPC hydropower project in Vietnam;?a questionnaire with 18 risk elements was designed and then delivered to experts in EPC hydropower project management area. Based on the risk model, 11 main risk elements were identified which can be categorized into 3 groups.?Lastly, the current study proposed suggestions to reduce or avoid risks as well as approach to control risks.?Furthermore, the findings of this study can be a good managerial reference for project management teams who are working in other countries that have similar economic and investment environment to Vietnam to get their EPC construction project completed on schedule, thus ensuring the benefits to the government, the investor, the contractor, and the parties involved.

关键词： EPC Hydropower Project Risk Analysis and Evaluation Risk Control Prevent Risks

Directly immobilized DNA sensor for label-free detection of herpes virus

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Journal of Biomedical Science and Engineering 2009年第6期2卷 374-379页

作者： Phuong dinh Tam mai Anh Tuan Nguyen Duc Chien 不详

This paper reports the direct immobilization of deoxyribonucleic acid (DNA) sequences of Herpes simplex virus (5’–AT CAC CGA CCC GGA GAG GGA C–3’) on the surface of DNA sensor by using the cyclic voltammetric method with the presence of pyrrole. The potential was scanned from –0.7 volt to + 0.6 volt, the scanning rate was at 100mV/s. This kind of DNA sensor was developed to detect Herpes virus DNA in real samples. The FTIR was applied to verify specific binding of DNA sequence and conducting polymer, the morphology of conducting polymer doped with DNA strands was investigated by using a field emission scanning electron microscope (FE-SEM). The results showed that output signal given by coimmobilized DNA/PPy membrane sensor was better than that given by APTS immobilized membrane sensors. The sensor can detect as low as 2 nM of DNA target in real samples.

关键词： DNA Sensor Hybridization APTS

A Note on Skew Cyclic Codes over a Class of Rings

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Algebra Colloquium 2020年第4期27卷 703-712页

作者： Hai Q.dinh Bac T.Nguyen Songsak Sriboonchitta Division of Computational Mathematics and Engineering Institute for Computational Science Ton Due Thang University Ho Chi Minh CityVietnam Faculty of Mathematics and Statistics Ton Due Thang University Ho Chi Minh CityVietnam Department of Basic Sciences University of Economics and Business Administration Thai Nguyen UniversityThai Nguyen ProvinceVietnam Centre of Excellence in Econometrics Faculty of Economics Chiang Mai UniversityChiang Mai 52000Thailand

We study skew cyclic codes over a class of rings R=F0■F1■⋯■Ft−1,where each Fi(i=0,…,t−1)is a finite *** prove that a skew cyclic code of arbitrary length over R is equivalent to either a usual cyclic code or a quasi-cyclic code over ***,we discuss possible extension of our results in the more general setting ofδR-dual skew constacyclic codes over R,whereδR is an automorphism of R.

关键词： skew constacyclic codes dual codes repeated-root codes quasi-cyclic codes local rings