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china Communications 2019年第3期16卷 92-102页

作者： Tan N.nguyen Minh Tran thanh-Long nguyen Miroslav Voznak Wireless Communications Research Group Faculty of Electrical and Electronics Engineering Ton Duc Thang University Optoelectronics Research Group Faculty of Electrical and Electronics Engineering Ton Duc Thang University Center for Information Technology Ho Chi Minh City University of Food Industry Faculty of Electrical Engineering and Computer Science VSB-Technical University of Ostrava

In this paper, the system performance of a decode-and-forward(DF) full-duplex(FD) adaptive relaying network over the Rician fading environment is proposed, analyzed and demonstrated. In the first stage, the system is presented with the energy harvesting and information transmission processes. After that, the analytical expressions of the achievable throughput, the outage probability, and symbol error ratio(SER) were proposed, analyzed and demonstrated. Finally, the analytical results are also demonstrated by Monte-Carlo simulation in comparison with the closed-form expressions in the influence of the key system parameters. The results show that the analytical and simulated results match for all possible parameter values.

关键词： relaying network throughput outage probability SER wireless energy harvesting(EH)

Occurrence of microcystins in water,sediment,and aquatic animals in Dau Tieng Reservoir,Vietnam

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Journal of Oceanology and Limnology 2024年第6期42卷 1751-1763页

作者： thanh Luu PHAM Manh Ha BUI Tan Duc nguyen thanh Son DAO Faculty of Environment and Labour Safety Ton Duc Thang UniversityHo Chi Minh City 700000Vietnam Faculty of Environment Saigon UniversityHo Chi Minh City 700000Vietnam Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention and Guangdong Provincial Key Laboratory of Marine BiotechnologyShantou UniversityShantou 515063China Faculty of Environment and Natural Resources Ho Chi Minh City University of Technology(HCMUT)Ho Chi Minh City 700000Vietnam Asian Center for Water Research(Centre Asiatique de Recherchesur l’Eau CARE)Ho Chi Minh City University of Technology(HCMUT)Vietnam National UniversityHo Chi Minh City 700000Vietnam

This study investigates the variations of microcystins(MCs)in water,cyanobacterial blooms,sediment,and aquatic organisms collected from the Dau Tieng Reservoir(DTR).*** liquid chromatography(HPLC)was employed to measure MC concentrations in various target *** indicate that Microcystis *** as the primary MC producer in the *** average concentrations of analyzed MCs in surface water ranged from 1.10 to 5.54μg/L,temporally and *** sediment,average concentrations varied from 0.15 to 1.13μg/g wet weight(WW)temporally and from 0.41 to 0.72μg/g WW *** were detected in different organs of fish species(Oreochromis *** Labiobarbus sp.)and in the entire soft tissues of bivalve(Corbicula sp.)and gastropod(Assiminea sp.).The highest observed MC concentration in July was 0.83±0.22μg/g WW in the intestines of fish Oreochromis *** presence of MCs in grass shrimp Palaemonetes *** observed solely in June,reaching a concentration of 0.28±0.19μg/g *** is the first report of MC accumulation in the grass shrimp Palaemonetes *** field *** the bivalve Corbicula sp.,the presence of analyzed MCs was consistent throughout the study period,except for March and September,with the highest concentrations in July at 0.77±0.1μg/g *** correlation analysis revealed significant positive correlations between MCs in water and sediment with MC concentrations in aquatic animals,indicating the potential transfer of MCs across different trophic *** estimated daily intake values for analyzed MCs indicate that fish collected from the DTR are considered safe for consumption,as long as only the edible organs,such as the muscle,are ***,bivalves or gastropods collected from the DTR are not safe for human *** study underscored the importance of monitoring MC accumulation in aquatic animals used as food to mitigate adverse effects on human health.

关键词： aquatic animal bioaccumulation cyanotoxin health risk toxic cyanobacteria

Green synthesis of three-dimensional magnesium ferrite/titanium dioxide/reduced graphene from Garcinia mangostana extract for crystal violet photodegradation and antibacterial activity

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Journal of Semiconductors 2023年第12期44卷 111-124页

作者： Tong Hoang Lin Che Quang Cong nguyen thanh Hoai Nam Hoang An nguyen Duy Hai Ton That Buu Thoi Le Nhat Binh Hoang Le Minh Lam thanh Ngan Hoang Thuy Kim Ngan Du chi Vi Ta Dang Khoa nguyen Huu Hieu VNU-HCM Key Laboratory of Chemical Engineering and Petroleum Processing(Key CEPP Lab)Ho Chi Minh City University of Technology(HCMUT)268 Ly Thuong Kiet StreetDistrict 10Ho Chi Minh CityVietnam Faculty of Chemical Engineering Ho Chi Minh City University of Technology(HCMUT)268 Ly Thuong Kiet StreetDistrict 10Ho Chi Minh CityVietnam Vietnam National University Ho chi Minh City(VNU-HCM) Linh Trung WardThu Duc CityVietnam

In this study,three-dimensional porous magnesium ferrite/titanium dioxide/reduced graphene oxide(Mg Fe_2O_(4)-GM/TiO_(2)/rGO(MGTG))was successfully synthesized via green and hydrothermal-supported co-precipitation methods using the extract of Garcinia mangostana(***)as a reducing *** characterization results indicate the successful formation of the nano/micro Mg Fe_(2)O_(4)(MFO)and TiO_(2) on the structure of the reduced graphene oxide(rGO),which can also act as efficient support,alleviating the agglomeration of the nano/micro MFO and TiO_(2).The synergic effects of the adsorption and photodegradation activity of the material were investigated according to the removal of crystal violet(CV)under ultraviolet *** effects of catalyst dosage,CV concentration,and p H on the CV removal efficiency of the MGTG were also *** to the results,the CV photodegradation of the MGTG-200 corresponded to the pseudo-first-order kinetic *** reusability of the material after 10 cycles also showed a removal efficiency of 92%.This happened because the materials can easily be recollected using external *** addition,according to the effects of different free radicals·O_(2)^(-),h^(+),and·OH on the photodegradation process,the photocatalysis mechanism of the MGTG was also thoroughly *** antibacterial efficiency of the MGTG was also evaluated according to the inhibition of the Gram-positive bacteria strain Staphylococcus aureus(***).Concurrently,the antibacterial mechanism of the fabricated material was also *** results confirm that the prepared material can be potentially employed in a wide range of applications,including wastewater treatment and antibacterial activity.

关键词： magnesium ferrite titanium dioxide reduced graphene oxide Garcinia mangostana photodegradation antibacterial

Using Adaptive Gain Scheduling LQR Method Control of Arm Driven Inverted Pendulum System Based on PIC18F4431

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Journal of Harbin Institute of Technology(New Series) 2013年第4期20卷 85-92页

作者： Huu Chan thanh nguyen An-Wen Shen Department of Control Science and Engineering HuaZhong University of Science and Technology

The arm driven inverted pendulum system is a highly nonlinear model, muhivariable and absolutely unstable dynamic system so it is very difficult to obtain exact mathematical model and balance the inverted pendulum with variable position of the ann. To solve this problem, this paper presents a mathematical model for arm driven inverted pendulum in mid-position configuration and an adaptive gain scheduling linear quadratic regulator control method for the stabilizing the inverted pendulum. The proposed controllers for arm driven inverted pendulum are simulated using MATLAB-SIMULINK and implemented on an experiment system using PIC 18F4431 mieroeontroller. The result of experiment system shows the control performance to be very good in a wide range stabilization of the arm position.

关键词： Arm Driven Inverted Pendulum (ADIP) adaptive gain scheduling LQR control LQR control swing up pendlum

The Mediating Role of Religious Beliefs in the Relationship between Well-Being and Fear of the Pandemic

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International Journal of Mental Health Promotion 2023年第9期25卷 1019-1031页

作者： Van-Son Huynh thanh-Thao Ly My-Tien nguyen-Thi Xuan thanh Kieu nguyen Gallayaporn Nantachai Vinh-Long Tran-chi Faculty of Psychology Ho Chi Minh City University of EducationHo Chi Minh City700000Vietnam Faculty of Social Sciences and Public Relations HUTECH UniversityHo Chi Minh City700000Vietnam Department of Medical Services Ministry of Public HealthSomdet Phra Sungharaj Nyanasumvara Geriatric HospitalChon Buri20150Thailand Department of Psychiatry Faculty of MedicineChulalongkorn UniversityBangkok10330Thailand

Religion is one of the social entities that has had a significant impact on the *** study’s goals are to investigate the relationship between well-being and fear of COVID-19,as well as to test whether religious beliefs mediate the effect of wellbeing on fear of *** sample comprised of 433 participants in *** Sample t-Test,One-way ANOVA,mediation analysis were used to analyze the *** the levels of well-being,individuals who engage in religious services daily have higher levels than those hardly and never attend,and people from the age of 18 to 30 have higher levels than individuals from 31 to above 60 *** addition,people aged from 51 to above 60 have higher levels of religious beliefs than people aged from 18 to *** experience more fear of COVID-19 compared to *** latter illustrates that religious beliefs mediate the effect of well-being on fear of *** workers and clinicians must prioritize older adults and people with chronic diseases for early mental interventions,and they should be aware of the role of religion in psychological treatment integration.

关键词： Religious beliefs well-being fear pandemic Vietnam

A comparative analysis of weight-based machine learning methods for landslide susceptibility mapping in Ha Giang area

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Big Earth Data 2023年第4期7卷 1005-1034页

作者： thanh Trinh Binh thanh Luu Trang Ha Thi Le Duong Huy nguyen Trong Van Tran Thi Hai Van nguyen Khanh Quoc nguyen Lien Thi nguyen Faculty of Computer Science Phenikaa UniversityYen NghiaHa DongHanoi 12116Vietnam Phenikaa Research and Technology Institute(PRATI) A&A Green Phoenix Group JSCNo.167 Hoang NganTrung HoaCau GiayHanoi 11313Vietnam Northwestern Geological Division General Department of Geology and Minerals of VietnamHanoiVietnam Youth union office Thuyloi University175 Tay SonDong DaHanoiVietnam Center of Remote Sensing and Geohazards Vietnam Institute of Geosciences and Mineral ResourcesHanoiVietnam

Landslide susceptibility maps (LSMs) are very crucial for planningpolicies in hazardous areas. However, the accuracy and reliability ofLSMs depend on available data and the selection of suitable *** study is conducted to produce LSMs by combinations of machinelearning methods and weighting techniques for Ha Giang province,Vietnam, where has limited data. In study area, we gather 11 landslideconditioning factors and establish a landslide inventory *** the weights of classes (or factors) is very important toprepare data for machine learning methods to generate LSMs. Wefrst use frequency ratio (FR) and analytic hierarchy process (AHP)techniques to generate the weights. Then, random forest (RF), supportvector machine (SVM), logistic regression (LR), and AHP methods arecombined with FR and AHP weights to yield accurate and reliableLSMs. Finally, the performance of these methods is evaluated by fivestatistical metrics, ROC and R-index. The empirical results have shownthat RF is the best method in terms of R-index and the five metrics, *** rate (0.9661), FP rate (0.0), ACC (0.9835), MAE (0.0046), and RMSE(0.0350) for this study area. This study opens the perspective of weightbasedmachine learning methods for landslide susceptibility mapping.

关键词： Landslide logistic regression random forest SvM Vietnam

The mechanism and effects of subgrade fluidisation under ballasted railway tracks

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Railway Engineering Science 2020年第2期28卷 113-128页

作者： Buddhima Indraratna Mandeep Singh thanh Trung nguyen Centre for Geomechanics and Railway Engineering University of WollongongWollongong CityNSW 2522Australia Australian Research Council(ARC)Industrial Transformation Training Centre ITTC-RailUniversity of WollongongWollongong CityNSW 2522Australia

The rapid growth in railway infrastructure and the construction of high-speed heavy-haul rail network,especially on ground that is basically unsuitable,poses challenges for geotechnical engineers because a large part of the money invested in the development of railway lines is often spent on track *** fact around the world,the mud pumping of subgrade fines is one of the common reasons why track performance deteriorates and track stability is *** article presents a series of laboratory tests to examine following aspects of mud pumping:(1)the mechanisms of subgrade fluidisation under undrained condition,(2)the effects of mud pumping on the engineering characteristics of ballast,and(3)the use of vertical drains to stabilize subgrade under cyclic *** undrained cyclic triaxial testing on vulnerable soft subgrade was performed by varying the cyclic stress ratio(CSR)from 0.2 to 1.0 and the loading frequency f from 1.0 to 5.0 *** is seen from the test results that for a specimen compacted at an initial dry density of 1790 kg/m3,the top portion of the specimen fluidises at CSR=0.5,irrespective of the applied loading *** cyclic railway loading,the internal redistribution of water at the top of the subgrade layer softens the soil and also reduces its *** response to these problems,this paper explains how the inclusion of vertical drains in soft subgrade will help to prevent mud pumping by alleviating the build-up of excess pore pressures under moving train loads.

关键词： Mud pumping Ballasted track Subgrade fluidisation Fouled ballast Prefabricated vertical drains

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 nguyen 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

Engine performance and combustion characteristics of a direct injection compression ignition engine fueled waste cooking oil synthetic diesel

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International Journal of Coal Science & Technology 2020年第3期7卷 560-570页

作者： thanh Viet nguyen Khanh Duc nguyen Nang Xuan Ho Vinh Duy nguyen Department of Internal Combustion Engine School of Transportation EngineeringHanoi University of Science and TechnologyHanoiViet Nam Faculty of Vehicle and Energy Engineering Phenikaa UniversityYen NghiaHa-Dong DistrictHanoiViet Nam

Biodiesels produced from various feedstocks have been considered as alternative fuels used in internal combustion engines without major *** research focuses on producing biodiesel from waste cooking oil(WCOSD)by the catalytic cracking method using MgO as the catalyst and comparing the engine operating characteristics of the test engine when using WCOSD and traditional diesel(CD)as test *** a result,the brake power of the test engine fueled WCOSD,and traditional diesel is ***,the engine fuel consumption in the case of using WCOSD is slight increases in some operating ***,the nitrogen oxides emissions of the test engine fueled WCOSD are higher than those of CD at all tested *** trend is opposite for hydrocarbon emission as the HC emission of the engine fueled by WCOSD reduces 26.3%on *** smoke emission of the test engine in case of using WCOSD is lower 17%on average than that of ***,the carbon monoxide emissions are lower at the low and medium loads and higher at the full *** results show that the new biodiesel has the same characteristics as those of commercial biodiesel and can be used as fuel for diesel engines.

关键词： Feedstock Waste cooking oil Engine characteristics Exhaust missions Ignition timing Fuel consumption

Optimization Agricultural Supply Chain:A Case Study of Fertilizer Supplier Selection

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Computers, Materials & Continua 2022年第8期72卷 4057-4068页

作者： nguyen Van thanh nguyen Thi Kim Lan Syed Tam Husain nguyen Hoang Hai nguyen Viet Tinh Faculty of Commerce Van Lang UniversityHo Chi Minh CityVietnam International Education Institute Van Lang UniversityHo Chi Minh CityVietnam

The 21st century is associated with the IndustrialRevolution 4.0 and the organic agriculture trend,making the utilization of high-quality fertilizers,abundant nutritional content,economical,and no affect to environment *** to the new concept,clean agricultural production and organic agricultural products are not allowed to excessively use synthetic chemicals such as chemical fertilizers,and plant protection drugs,but priority is to use manure,organic fertilizers,and natural mineral *** must meet the balanced nutritional requirements of crops,maintain,and improve the fertility of the ground,protect the surrounding ecosystem,and leave harmful effects in agricultural products,products with high quality,safe for users and high economic efficiency for *** achieve the above goal,the selection of a fertilizer supplier is an important decision,supporting the supply chain’s sustainable development,fertilizer supplier selection is a multicriteria decision making model,the decision maker must assess all qualitative and quantitative *** this paper,the author proposed an integer decision making model including Fuzzy Analytic Hierarchy Process(FAHP)and Complex Proportional Assessment of Alternatives(COPRAS)for fertilizer supplier *** weightings of the criteria are calculated by using FAHP,COPRAS is then applied for ranking some potential fertilizer *** efficiency of the proposed models is proved by a case study conducted in a farm located in the south of *** research is the first fertilizer supplier evaluation and se-lection model in Vietnam by interviewing experts and reviewing the ***-search result is to provide a case study on evaluating supplier in agricultural supply chain utilizing the model proposed by the combination of FAHP and COPRAS models.

关键词： Fertilizer industry optimization model fuzzy theory agricultural supply chain