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Assessment of Water Quality in Shrimp Culture Areas of the Mekong Delta

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Journal of Agricultural Science and Technology(B) 2014年第7期4卷 571-580页

作者： Vu ngoc Ut nguyen Ba Quoc Son Sam Phone College of Aquaculture and Fisheries Can Tho University Can Tho City 70 000 Vietnam

A Study on Effects of Blade Pitch on the Hydrodynamic Performances of a Propeller by Using CFD

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Journal of Shipping and Ocean Engineering 2018年第1期8卷 36-42页

作者： nguyen Chi Cong LUONG ngoc Loi NGO Van He Vietnam Marine University Haiphong 180000 Vietnam Hanoi University of Science and Technology Hanoi 10000 Vietnam

The main objective of this work is to use the CFD (Computational Fluid Dynamics) technique to study the effects of pitch ratio on the controllable pitch propeller"s thrust characteristic. The propeller analyzed is at the following design condition: diameter of 3.65 m, speed of 200 rpm, blade number of 4, average pitch of 2.459 m, pitch ratio at 0.7 of 0.6737. The first stage involves the mesh generation and refinement on domain of the designed propeller. The second stage deals with the identification of initial and boundary conditions of the mesh-equipped module. In the final stage, various results are calculated and analyzed for pitch ratio affecting on the propeller"s thrust characteristic. The achieved results are the basis design and improving efficiency of the controllable pitch propeller.

关键词：推进器 CFD 沥青水动力学表演设计条件液体动力学边界条件

Monitoring Heart Rate Variability Based on Self-powered ECG Sensor Tag

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Journal of Electronic & Information Systems 2022年第2期4卷 10-20页

作者： Nhat Minh Tran ngoc-Giao Pham Thang Viet Tran Department of Telecommunication Sai Gon UniversityVietnam Department of Computing Fundamentals FPT UniversityHanoiVietnam Department of Science and Technology Nguyen Tat Thanh UniversityHo Chi Minh CityVietnam

This paper proposes a batteryless sensing and computational device to collect and process electrocardiography(ECG)signals for monitoring heart rate variability(HRV).The proposed system comprises of a passive UHF radio frequency identification(RFID)tag,an extreme low power microcontroller,a low-power ECG circuit,and a radio frequency(RF)energy *** microcontroller and ECG circuits consume less power of only~30μA and~3 mA,***,the proposed RF harvester operating at frequency band of 902 MHz~928 MHz can sufficiently collect available energy from the RFID reader to supply power to the system within a maximum distance of~2 *** extract R-peak of the ECG signal,a robust algorithm that consumes less time processing is also *** information of R-peaks is stored into an Electronic Product Code(EPC)Class 1st Generation 1st compliant ID of the tag and read by the *** reader is functioned to collected the R-peak data with sampling rate of 100ms;therefore,the user application can monitor fully range of *** performance of the proposed system shows that this study can provide a good solution in paving the way to new classes of healthcare applications.

关键词： Batteryless ECG sensor Heart rate monitoring UHF RFID

Effect of Yb^(3+) concentration on Er^(3+) luminescence properties of sol-gelderived silica-alumina xerogels

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Optoelectronics Letters 2006年第5期2卷 354-357页

作者： K.Tran ngoc H.Pham Thanh C.nguyen Duc C.Armellini A.Chiasera M.Ferrari Y.Jestin M.Montagna E.Moser S.Pelli G.C.Righini CNR-IFN Istituto di Fotonica e Nanotecnologie CSMFO groupvia Sommarie 14I-38050 PovoTrentoItaly ITIMS-Hanoi University of Technology No 1Dai Co VietHanoiVietnam Dipartimento di Fisica Università di TrentoCSMFO groupvia Sommarive 14I-38050 PovoTrentoItaly CNR-IFAC Nello Carrara Institute of Applied Physics Lab.of Optoelectronic TechnologiesVia Madonna del Piano 1050019 Sesto FiorentinoFirenzeItaly

Er3+/Yb3+ co-doped silica-alumina monolithic xerogels were prepared with the same concentration on 2 000 Er/Si ppm and 6 000 Al/Si *** Yb/Si content was varied from 0 to 4 000 *** of the samples was achieved by thermal treatment in air at 950 ℃ for 120 hours with a heating rate 0.1 ℃/*** spectroscopy was used to obtain information about the effective excitation efficiency of Er3+ ions by co-doping with Yb 3+ *** infrared-to-visible up-conversion luminescence has been investigated upon continuous wave excitation at 980 *** samples exhibit red,green and blue up-conversion *** is found that the intensity of up-conversion luminescence increases with increasing Yb3+ doping *** opposite behavior is observed for the 4I13/2 luminescence of the Er3+ ions.

关键词：铒离子二氧化硅干凝胶光致发光

PRRS in Vietnam and Its Diagnosis

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Journal of Life Sciences 2015年第6期9卷 272-276页

作者： ngoc Hai nguyen Thi Hong Vi Vuong Tan Hung Vo Department of Infectious Diseases and Public Health Faculty of Animal Science and Veterinary Medicine Nong Lam UniversityHo Chi Minh city 0084-8 Vietnam HanViet Veterinary Diagnosis Laboratory Nong Lam University Ho Chi Minh city 0084-8 Vietnam

Genotyping 42 serum samples taken from the pigs in the oubreaks from 2009 to 2013 with RT-PCR and nested RT-PCR, showed more than 80% of samples were positive with Chinese PRRSV clade, and the others were European and North American classical PRRSV genotypes. Ten serum samples from unnapprent PRRS herds were examined for antibodies against PRRSV with ELISA and also for PRRSV with RT-PCR. It was clearly that the titer of antibodies against PRRSV by ELISA test could not be used for interpreting PRRSV infection. In despite of PRRS vaccination or non-vaccination, a risk of PRRSV infection and re-infection exist, utilizing RT-PCR in combination with serology will give the producer and veterinarian PRRSV more exact situation in the herds.

关键词： PRRSV感染 RT-PCR ELISA抗体 ELISA试验越南诊断 PRRS疫苗血清学

Rutting Resistance of Asphalt Pavement Mixes by Finite Element Modelling and Optimisation

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Journal of Construction Research 2019年第2期1卷 1-7页

作者： Chau Phuong Ngo Van Bac nguyen Thanh Phong nguyen ngoc Bay Pham Van Phuc Le Van Hung nguyen Faculty of Civil Engineering University of Transport and CommunicationsCampus in Ho Chi Minh CityVietnam College of Engineering and Technology University of DerbyDerbyUnited Kingdom

Asphalt pavement rtting is a major safety concem and is one of the main distress modes of asphalt *** into asphalt pavement mixes that provide strong resistance for nutting is considered of great significance as it can help provide extended pavement life and significant cost savings in pavement maintenance and *** objectives of this study are to develop numernical models to investigate the ntting of asphalt concrete pavements and to find optimal design of asphalt pave-ment mix for nutting ***-dimensional Finite Element mod-els were first developed to simulate both the axial compression and wheel track testing in which a visco elastic-plastic material model was used to predict the ntting of the asphalt concrete pavements.A strain hardening creep model with the material parameters developed from experimental testing was employed to model the time-dependent characteristics of the asphalt concrete *** results were validated against the pre-vious experimental wheel track test results of different pavement ***,optimisation techniques using the Design Of Experiments method were applied to the simulation rutting results by varying creep parameters to identify their effects on rutting resistance in order to obtain an optimal asphalt pavements *** results of this paper clearly demonstrate an efficient and effective experimental-numerical method and tool set towards optimal design for asphalt concrete pavements for rutting resis-tance.

关键词： Visco-elastic-plastic Creep Asphalt pavement Rutting Wheel track testing Finite Element modelling Design of experiments Optimisation

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辞职去重庆留学

神州学人 2016年第4期 18-18页

作者： nguyen quynh HOA 重庆大学

我在越南的时候,只知道中国的北京、上海、深圳等大城市,直到我的汉语老师给我介绍中国的一个被叫作"山城"的城市——重庆,我才知道重庆是中国四大直辖市之一。老师说那座城市有山有水,在我的脑海里慢慢画出一幅山水画。2013年夏天,我... 详细信息

我在越南的时候,只知道中国的北京、上海、深圳等大城市,直到我的汉语老师给我介绍中国的一个被叫作"山城"的城市——重庆,我才知道重庆是中国四大直辖市之一。老师说那座城市有山有水,在我的脑海里慢慢画出一幅山水画。2013年夏天,我收到重庆大学中国政府奖学金录取通

关键词：长安汽车

Application of Remote Sensing and GIS Technology in Mapping Partition Saline Intrusion to Paddy Land:A Case Study at Phu Vang District,Thua Thien Hue Province

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Journal of Agricultural Science and Technology(A) 2017年第B10期7卷 48-59页

作者： nguyen Hoang Khanh Linh Le ngoc Phuong Quy Truong Do Minh Phuong nguyen Trac Ba An Faculty of Land Resources and Agricultural Environment University of Agriculture and ForestryHue University102 Phung Hung StreetHue 530000Vietnam

Adapting and restricting salinity intrusion in Vietnam is being concerned by more researchers as well as the local *** study aimed to use remote sensing and geographic information system(GIS)technology for mapping paddy areas and salinity intrusion in spring crop 2015 at Phu Vang district,thereby helping precondition for assessing and monitoring changes in salinity intrusion to serve for salinization management in study *** on acquisition imagery,land use map and normalized difference vegetation index(NDVI)were extracted to interpolate the salinity of area by combining the laboratory analysis of collected soil samples from the *** result showed that there were 1,067.107 ha of salinity land area accounting for 10.04%of the rice land in Phu Vang district,where the moderate salinity level was 180.67 ha and low salinity level was 866.431 *** salinity rice land was mainly distributed in Vinh Ha commune,Phu An commune and Phu Dien *** salinity in this area ranged from 0.4 mS/cm to 1.41 mS/cm and the moderate salinity was approximately 0.9 mS/***,this research also showed that the salinity(electrical conductivity)and the development of vegetation(NDVI)were closely related with each other up to 61.4%.

关键词： GIS remote sensing normalized difference vegetation index salinity intrusion paddy land

Assesment of Frequency-Magnitude of Extreme Rainfall Events-Case Study of the MeKong River Delta

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Journal of Environmental Science and Engineering(B) 2015年第3期4卷 161-168页

作者： Pham Hai An Tran Anh Tu Tran Dinh Lan nguyen ngoc Tien Institute of Marine Environment and Resources VAST Haiphong 180000 Vietnam Institute of Marine Geology and Geophysics VAST Hainoi 1000000 Vietnam

Extreme rainfall events are primary natural hazards, which cause a severe threat to people and their properties in populated cities, which are normally located in coastal areas in Vietnam. Analysing these events by using a data series observed over years will support us to draw a picture of how the climate change impact on local environments. The purpose of this report is to understand the characteristics of the extreme rainfall events in MEKONG river delta (south VietNam). Daily rainfall data in the period of 30 years for a meteorological station in each area were collected from the Vietnam National Hydro-meteorological Service. The extreme rainfall events were defined as those exceeding the 95th percentile for each station. The analytical results show that the rainfall values (95th percentile) are 37.4 mm/day at Nam Can station, 27 mm/day at My Thanh station, 22.4 mm/day at Hoa Binh station, 23.8 mm/day at Binh Dai station and 22.7 mm/day at Ben Trai station. The highest rainfall data ever recorded are 246.4 mm/day (Nam Can), 174.5 mm/day (My Thanh), 179 mm/day (Hoa Binh), 187.3 mm/day (Binh Dai) and 136.3 mm/day (Ben Trai) during 1983-2012. The result of the Mann-Kendall tests show that there was a significant creasing of the rainfall at Nam Can, My Thanh station in two periods (1983-2012, 1998-2012) while no clear trend of the rainfall was recoreded at Hoa Binh, Binh Dai, Ben Trai station. In order to estimate the return period of the extreme rainfall events, the method General Extreme Value Distribution was used to calculate frequent distribution. The magnitudes of daily maximum rainfall were from 2 to 100 years. The results of return period show that maximum rainfalls are 46.6 mm at Nam Can station (highest) and 31.4 mm at Hoa Binh station (lowest) during 50 years. Similarly, maximum rainfalls are expected to be about 55.1 mm at Nam Can station and 37.2 mm at Hoa Binh station for 100 years.

关键词：降雨量三角洲湄公河事件 DAPI 幅度检测案例