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Aquaculture and Fisheries 2021年第4期6卷 432-440页

作者： Khanh Q.nguyen Phu D.tran Luong t.nguyen phuong V.to Corey J.morris Nha trang University 2 Nguyen Dinh ChieuNha TrangViet Nam Fisheries and Oceans Canada St.John’sNL A1C 5X1Canada

the use of high-power lights during night-time purse seining is common in ***,metal halide(mH)lamps are used in the commercial fishery to attract fish,however these lights require more energy,have a shorter lifespan,and lower chromatic performance than light emitting diode(LED)*** study examined catch efficiency and fuel consumption when using LED lamps in combination with reduced numbers of mH lamps(10.24 kW),compared to conventional lighting(28.6 kW),used during purse seining off the coast of Ninh thuan province,*** economic performance associated with using LED lamps in this fishery was also *** found no significant differences in catch rates between the different light treatments,however fuel consumption was significantly *** consumption per nightly trip using LED with mH lamps was 70.8 l(11.1 l/h)compared to114 l(17.45 l/hr)using mH lamps alone,an estimated 37.9%reduction in fuel *** investment in LED lamps by a fishing enterprise will require additional initial costs,however our analysis revealed the financial break-event point can be reached after approximately 101 nightly trips when the fuel price is at the 2015 level of USD$0.74 per *** enterprises can increase their profitability,and reduce CO2 emissions,by using LED lamps in the Vietnamese purse seine fishery.

关键词： LED light Purse seine fishery Fuel consumption Catch comparison Economic efficiency

CLASSIFICAtION OF SOLUtIONS tO HIGHER FRACtIONAL ORDER SYStEmS

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Acta mathematica Scientia 2021年第4期41卷 1302-1320页

作者： phuong LE Faculty of Economic mathematics University of Economics and LawHo Chi Minh CityVietnam VietnamNational UniversityHo Chi Minh CityVietnam

Let 00 for all s,t≥*** main technique we use is the method of moving spheres in integral *** our assumptions are more general than those in the previous literature,some new ideas are introduced to overcome this diffi... 详细信息

Let 0two nonnegative *** study nonnegative classical solutions of the system{(-△)^(α/2)u=f(u,v)in R^(n),(-△)^(β/2)v=g(u,v)in R^(n),and the corresponding equivalent integral *** classify all such solutions when f(s,t)is nondecreasing in s and increasing in t,g(s,t)is increasing in s and nondecreasing in i,and f(μ^(n-α)s,μ^(n-β)t)/μ^(n-α),g(μ^(n-α)s,μ^(n-β)t)/μ^(n-β)are nonincreasing in μ>0 for all s,t≥*** main technique we use is the method of moving spheres in integral *** our assumptions are more general than those in the previous literature,some new ideas are introduced to overcome this difficulty.

关键词： Higher fractional order system integral system general nonlinearity method of moving spheres classification of solutions

Effect of Poly-Alkylene-Glycol Quenchant on the Distortion, Hardness, and microstructure of 65mn Steel

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Computers, materials & Continua 2021年第6期67卷 3249-3264页

作者： thi Xuan tran Xuan phuong nguyen Duong Nam nguyen Dinh toai Vu minh Quang Chau Osamah Ibrahim Khalaf Anh tuan Hoang Hanoi University of Science and technology HanoiVietnam Ho Chi minh City University of transport Ho Chi Minh CityVietnam Vietnam maritime University HaiphongVietnam Industrial University of Ho Chi minh City(IUH) Ho Chi Minh CityVietnam Al-Nahrain Nanorenewable Energy Research Center Al-Nahrain UniversityBaghdadIraq Ho Chi minh city University of technology(HUtECH) Ho Chi Minh CityVietnam

Currently,the 65mn steel is quenched mainly by oil *** though the lower cooling rate of oil compared to water reduces the hardness of steel post quenching,the deforming and cracking of parts are often *** the other hand,the oil media also has the disadvantage of being ammable,creating smoke that adversely affects the *** poly alkylene glycol(PAG)polymer quenchant is commonly used for quenching a variety of steels based on its advantages such as non-ammability and exible cooling rate subjected to varying concentration and stirring *** article examines the effect of PAG polymer quenching solution(with concentrations of 10%and 20%)on deformation,hardness,and microstructure of C-ring samples made of 65mn ***,the performance of PAG polymer quenchant is also compared with those of two common quenching solutions:Water and *** cooling in water,the C-ring samples had the largest deformation and 2 times higher than the results obtained when a 10%PAG solution was *** particular,similar levels of deformation on the C-ring samples were observed in both cases of 20%PAG solution and oil as the primary quenching ***,the hardness level measured between the sampled parts quenched in the 20%PAG solution appeared to be more uniform than that obtained from the oil-quenched *** study of the microscopic structure of steel by optical microscopy combined with X-ray diffraction showed that the water hardened sample exhibited cracks and comprised of two phases,martensite and retained *** to the results of Electron Back Scattering Diffraction(EBSD)analysis and backscattering electronic image(BSE),the content of austenite residue in the sample when the sample was cooled in PAG 10 and 20%solution was 3.21%and 4.73%,respectively and smaller than the measurements obtained from oil quenching ***,the 65mn steel is cooled in 20%PAG solution for high hardness and more evenly distributed than when it is q

关键词： Polyethylene glycol electron backscattering diffraction quenching media cooling rate backscattering electronic image

A mixed-integer Linear Programming model for Defining Customer Export Limit in PV-rich Low-voltage Distribution Networks

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Journal of modern Power Systems and Clean Energy 2023年第1期11卷 191-200页

作者： Pedro P.Vergara Juan S.Giraldo mauricio Salazar Nanda K.Panda phuong H.nguyen Intelligent Electrical Power Grids(IEPG)Group Delft University of TechnologyDelft 2628CDThe Netherlands Energy transition Studies Group Netherlands Organisation for Applied Scientific Research(TNO)Amsterdam1043 NTThe Netherlands Electrical Energy Systems(EES)Group Eindhoven University of TechnologyEindhovenThe Netherlands IEEE

A photovoltaic(PV)-rich low-voltage(LV)distribution network poses a limit on the export power of PVs due to the voltage magnitude *** defining a customer export limit,switching off the PV inverters can be avoided,and thus reducing power *** on this,this paper proposes a mixed-integer nonlinear programming(mINLP)model to define such optimal customer *** mINLP model aims to minimize the total PV power curtailment while considering the technical operation of the distribution ***,a nonlinear mathematical formulation is ***,a new set of linearizations approximating the Euclidean norm is introduced to turn the mINLP model into an mILP formulation that can be solved with reasonable computational *** extension to consider multiple stochastic scenarios is also *** proposed model has been tested in a real LV distribution network using smart meter measurements and irradiance profiles from a case study in the *** assess the quality of the solution provided by the proposed mILP model,monte Carlo simulations are executed in OpenDSS,while an error assessment between the original mINLP and the approximated mILP model has been conducted.

关键词： Low-voltage distribution network photovoltaic(PV)curtailment optimal power flow monte Carlo simulations

Enhanced corrosion performance of magnesium phosphate conversion coating on AZ31 magnesium alloy

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transactions of Nonferrous metals Society of China 2017年第5期27卷 1087-1095页

作者： nguyen Van phuong manoj GUPtA Sungmo mOON Korea Institute of materials Science Gyeongnam 51508 Korea Department of mechanical Engineering National University of Singapore 119260 Singapore Korea University of Science and technology Daejeon 34113 Korea

magnesium phosphate conversion coating(mPCC)was fabricated on AZ31magnesium alloy for corrosion protection by immersion treatment in a simple mPCC solution containing mg2+and3PO4?*** mPCC on AZ31mg alloy showed micro-cracks structure and a uniform thickness with the thickness of about2.5μm after20min of phosphating *** composition analyzed by energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy revealed that the coating consisted of magnesium phosphate and magnesium hydroxide/oxide *** mPCC showed a significant protective effect on AZ31mg *** corrosion current of mPCC was reduced to about3%of that of the uncoated surface and the time for the deterioration process during immersion in0.5mol/L NaCl solution improved from about10min to about24h.

关键词： magnesium alloy AZ31 alloy magnesium phosphate conversion coating corrosion protection

thermodynamic Simulation on the Change in Phase for Carburizing Process

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Computers, materials & Continua 2021年第7期68卷 1129-1145页

作者： Anh tuan Hoang Xuan phuong nguyen Osamah Ibrahim Khalaf thi Xuan tran minh Quang Chau thi minh Hao Dong Duong Nam nguyen Ho Chi minh city University of technology(HUtECH) HoVietnam Ho Chi minh city University of transport Ho Chi Minh cityVietnam Al-Nahrain University Al-Nahrain Nanorenewable Energy Research CenterBaghdadIraq Hanoi University of Science and technology HanoiVietnam Industrial University of Ho Chi minh City(IUH) Ho Chi Minh cityVietnam Vietnam maritime University HaiphongVietnam

the type of technology used to strengthen the surface structure of machine parts,typically by carbon-permeation,has made a great contribution to the mechanical engineering industry because of its outstanding advantages in corrosion resistance and enhanced mechanical and physical ***,carbon permeation is considered as an optimal method of heat treatment through the diffusion of carbon atoms into the surface of alloy *** study presented research results on the thermodynamic calculation and simulation of the carbon permeability *** Fick’s law,the paper calculated the distribution of carbon concentration in the alloy steel after it is absorbed from the surface into the internal of the *** the SYSWELD software,an analysis was performed on the carbon permeability process to determine the distribution of carbon concentrations in 20Crmo steel that was then followed by a detailed analysis of the microstructure of the sample post the carburizing *** to the calculation results,the surface carbon content was 0.9%and steadily decreased into the *** 3 hours,the depth of the absorbent layer was measured at 0.5 mm for both the cylindrical and cubic *** analyzing the phase,the distribution of martensite phases such as ferrite/pearlite and residual austenite was also determined after the carburizing process.

关键词： Carburizing process 20Crmo steel thermodynamic analysis microstructure formation carbon concentration

Improving Supply Chain Performance through Supplier Selection and Order Allocation Problem

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Computers, materials & Continua 2022年第1期70卷 1667-1681页

作者： Chia-Nan Wang ming-Cheng tsou Chih-Hung Wang Viet tinh nguyen Pham Ngo thi phuong Department of Industrial Engineering and management National Kaohsiung University of Science and TechnologyKaohsiung80778Taiwan Department of Shipping technology National Kaohsiung University of Science and TechnologyKaohsiung80778Taiwan Department of International Business Shih Chien UniversityTaipei80778Taiwan Faculty of Commerce Van Lang UniversityHo Chi Minh City70000Vietnam Faculty of Industrial Engineering and management International UniversityHo Chi Minh City70000Vietnam

Suppliers play the vital role of ensuring the continuous supply of goods to themarket for *** businesses do not maintain a strong bond with their suppliers,they may not be able to secure a steady supply of goods and products for their *** a result of failure to deliver products,the production and business activities of the business can be delayed which leads to the loss of ***,each trading enterprise will have a variety of commodity supply chains withmultiple *** play an important role and contribute to the value of the entire supply *** any supplier encounters a problem,the whole supply chain of businesses will be affected and could lead to not guaranteeing the stable supply to the ***,suppliers can be seen as a threat to businesses where they have the ability to increase input prices or decrease the quality of the required products and services they *** quantity of the business,and the supply lead time directly affect the operations and reduce the profitability of the *** paper mainly focuses on the supplier selection problemunder a variety of price level and product families when using a two-phase fuzzy multi-objective linear *** objectives of the proposed model are to minimize the total purchasing and ordering cost in order to reduce the quantity of defective materials and the late-delivery components from ***,the piecewise linear membership function is applied in themodel to determine an optimal solution which is based on the requirement of decision makers under their fuzzy *** results of this study can be applied in various business environment and provide a reliable decision tool for choosing potential suppliers relating to these *** on the results,the company canmake a good decision on supplier selection;therefore,the company can improve the quality and quantity of their final *** is because,the best supplier can su

关键词： Supplier selection multi-objective linear programming multiprice level multi-product fuzzy sets

Anticaries and antimicrobial activities of methanolic extract from leaves of Cleistocalyx operculatus L.

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Asian Pacific Journal of tropical Biomedicine 2017年第1期7卷 43-48页

作者： phuong thi mai nguyen Nadin Schultze Christin Boger Zeyad Alresley Albert Bolhuis Ulrike Lindequist Department of Plant Biochemistry Institute of BiotechnologyVietnam Academy of Science and Technology Institute of Pharmacy University of Greifswald Department of Pharmacy and Pharmacology University of Bath

Objective: to investigate antimicrobial activities of methanolic extract of leaves of Cleistocalyx operculatus L.(C. operculatus) grown in ***: the methanolic extract of C. operculatus leaves was phytochemically screened and tested for its antimicrobial activity against six Gram-positive bacteria(three of which were antibiotic multiresistant Staphylococcus spp.), two Gram-negative bacteria,and one fungal species using an agar diffusion method. Anticaries activity was tested using p H drop and biofilm assays formed in 96-well plastic ***: Phytochemical screening revealed the presence of flavonoids and terpenes, in which flavonoid content was 6.8 mg/g dry material. Antibacterial activity of the C. operculatus extract was shown only against Gram-positive bacteria Staphylococcus aureus, Bacillus subtilis and Streptococcus mutans GS-5(S. mutans), and three multiresistant bacteria being Staphylococcus epidermidis 847, Staphylococcus haemolyticus 535 and Staphylococcus aureus North German epidemic strain. Interestingly, methanolic extract of C. operculatus leaves exhibited the anticaries activity against S. mutans in terms of inhibition of acid production and biofilm formation. Activity of two key enzymes responsible for acidogenicity of S. mutans, F-AtPase and phosphotransferase system were inhibited by the extract with IC_(50) of 51.0 and 98.0 m g/m L, respectively. Cytotoxicity of the extract against keratinocytes was found only for higher concentrations [IC_(50)=(119.98 ± 4.63) m g/m L].Conclusions: the methanolic extract of C. operculatus leaves has the potential for development of antimicrobial preparations, especially anticaries products.

关键词： Cleistocalyx operculatus Antibacterial activity Anticaries Cytotoxicity

A Risk-Based multi-Criteria Decision Analysis Approach to Evaluating transboundary Water Development—the Case of Lower mekong River Basin

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Journal of Environmental Protection 2021年第5期12卷 345-370页

作者： nguyen phuong Lan Graduate School of Global Environmental Studies Kyoto University Kyoto Japan

the Lower mekong River basin (LmB) covers the lower part of the mekong river basin, including Laos, thailand, Cambodia and Vietnam. Due to numerous pressures from high population growth and intensive hydropower development, the LmB has been facing significant challenges concerning its biodiversity and ecosystem. In 2017, mekong River Commission (mRC), an intergovernmental organisation founded in 1995 among LmB countries, established the Council Study, which analysed the impacts of water development scenarios concerning the environmental, socioeconomic aspects of the LmB. this paper explores the nature of risks to the LmB water development and subsequently evaluates LmB’s water development scenarios described in the Council Study by using a multi-criteria decision analysis (mCDA) method. mCDA method has been widely applied in the field of water resource management in order to assist the decision-making process by systematically evaluating a certain number of alternatives against well-selected criteria through a preference rating scheme. By implementing a risk-based comprehensive assessment of the LmB transboundary water, this study provides insights into the impacts of the increasing risks to the ecosystem and human beings on the water development of the basin over time, which assists to change the awareness and the perspective toward humans’ risks and transboundary river ecosystem of decision-makers. this paper provides valuable recommendations for mRC to improve their policy concerning benefit-sharing scheme, water planning and risk mitigation strategies.

关键词： Lower mekong Basin multi-Criteria Decision Analysis transboundary River Basin Water Development Scenario Ecosystem Risk

Polygonatum kingianum rhizome extract alleviates collagen antibody-induced arthritis by modulating proinflammatory cytokine production in mice

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Asian Pacific Journal of tropical Biomedicine 2020年第11期10卷 490-495页

作者： Huyen Do thi thanh phuong Ngo thi Hien nguyen thi thu Nga nguyen thi Hung Le Ngoc thao Dothi Ha Le minh Graduate University of Science and technology Vietnam Academy of Science and Technology18 Hoang Quoc VietNghia DoCau GiayHanoiVietnam Institute of Natural Products Chemistry Vietnam Academy of Science and Technology18 Hoang Quoc VietNghia DoCau GiayHanoiVietnam Hanoi Open University101 nguyen Hien str Hai Ba Trung Dist.HanoiVietnam Laboratory of Bioassay Institute of BiotechnologyVietnam Academy of Science and Technology18 Hoang Quoc VietNghia DoCau GiayHanoiVietnam Chemistry Lab Project Center for Research and Technology transferVietnam Academy of Science and Technology18 Hoang Quoc VietNghia DoCau GiayHanoiVietnam

Objective: to evaluate the anti-arthritic effects of Polygonatum kingianum rhizome extract using both in vitro and in vivo ***: Lipopolysaccharide-induced RAW 264.7 macrophages were treated with an ethanol extract of Polygonatum kingianum rhizomes at different concentrations to determine nitric oxide and prostaglandin E2(PGE2) production. For in vivo study, Polygonatum kingianum ethanol extract was further investigated for its antiinflammatory effect in a mouse model with collagen antibodyinduced arthritis. Phytochemical study of Polygonatum kingianum ethanol extract was also ***: Saponins(142 mg/g total yield) was the main component in the Polygonatum kingianum ethanol extract. 5α,8α-ergosterol peroxide,(E,E)-9-oxooctadeca-10,12-dienoic acid and 3-(2?-hydroxy-4?-methoxy-benzyl)-5,7-dihydroxy-8-methyl-chroman-4-one were isolated from the extract. Polygonatum kingianum ethanol extract exhibited potential anti-inflammatory effects by inhibiting nitric oxide and PGE2 production in RAW 264.7 cells in a dosedependent manner. the level of arthritis in mice with collagen antibody-induced arthritis was significantly reduced(Pter treatment with Polygonatum kingianum ethanol extract, particularly at a dose of 1 000 mg/kg body weight. Besides, the extract demonstrated the regulatory effects on serum tumor necrosis factoralpha, interleukin-6, and interleukin-10 in treated ***: Polygonatum kingianum ethanol extract has beneficial effects on inflammatory cytokine regulation and PGE2 inhibition in an experimental mouse model with collagen antibody-induced arthritis. the phytochemical screening reveals that the saponin, as the main component, and sterols(daucosterol and 5α,8α-ergosterol peroxide) from Polygonatum kingianum ethanol extract may contribute to its promising in vitro and in vivo anti-inflammatory activities.

关键词： inflammatory cytokine PGE2