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American Journal of Operations Research 2018年第2期8卷 82-91页

作者： nguyen Khac Minh nguyen Thanh trung Pham Van Khanh Thang Long Institute of Mathematics and Applied Science Hanoi Vietnam Faculty of Fundamental Science Military Academy of Logistics Hanoi Vietnam

Assume that we want to shell an asset with unknown drift but known that the drift is a two value random variable, and the initial distribution can be estimated. As time goes by, this distribution is updated and base on the probability of the drift takes the small one gives us the stopping rule. Research results show that the optimal strategy to sell the asset is if the initial probability that the drift receives a small value greater than a certain threshold then liquidates the asset immediately, otherwise the asset holder will wait until the probability of the drift receives a small value passing a certain threshold, it is the optimal time to liquidate the asset.

关键词： Optimal Stopping Time Incomplete Information Probability Process

Mean Threshold and ARNN Algorithms for Identification of Eye Commands in an EEG-Controlled Wheelchair

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Engineering（科研） 2013年第10期5卷 284-291页

作者： nguyen Thanh Hai nguyen Van trung Vo Van Toi Biomedical Engineering Department International University Vietnam National University Ho Chi Minh City Vietnam Faculty of Electrical-Electronics Engineering University of Technical Education Ho Chi Minh City Vietnam

This paper represented Autoregressive Neural Network (ARNN) and meant threshold methods for recognizing eye movements for control of an electrical wheelchair using EEG technology. The eye movements such as eyes open, eyes blinks, glancing left and glancing right related to a few areas of human brain were investigated. A Hamming low pass filter was applied to remove noise and artifacts of the eye signals and to extract the frequency range of the measured signals. An autoregressive model was employed to produce coefficients containing features of the EEG eye signals. The coefficients obtained were inserted the input layer of a neural network model to classify the eye activities. In addition, a mean threshold algorithm was employed for classifying eye movements. Two methods were compared to find the better one for applying in the wheelchair control to follow users to reach the desired direction. Experimental results of controlling the wheelchair in the indoor environment illustrated the effectiveness of the proposed approaches.

关键词： Autoregressive NN Model Threshold algorithm EEG Technology Eye Activity and Electrical Wheelchair

Taxonomic notes of three tea-plants(Camellia ***)recently described in Vietnam

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Beverage Plant Research 2022年第1期2卷 174-176页

作者： nguyen trung Thanh Luong Van Dung Le Nguyet Hai Ninh Quang Cuong Truong Shixiong Yang Faculty of Biology VNU University of Science334 Nguyen TraiHanoi 100000Vietnam Faculty of Biology Dalat UniversityPhu Dong ThienVuong str.01Dalat66106Lam DongVietnam Faculty of Nong Lam Hoa Lu UniversityNinh Binh 40000Vietnam Bidoup Nui Ba National Park Tran Hung Dao str.5EDalat66116Lam DongVietnam CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunming 650201YunnanChina

Camellia sinensis *** is a heterotypic synonym of *** *** flosculora and *** were excluded from ***.

关键词： notes Vietnam Camellia

Influence of dietary mannan oligosaccharides supplementation on fingerling clownfish, Amphiprion ocellaris (Cuvier, 1830)

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Journal of Coastal Life Medicine 2017年第8期5卷 325-329页

作者： Hoang Do-Huu trung Kien nguyen Vietnam Academy of Science&Technology(VAST)-Institute of Oceanography 01 Cau DaNha TrangVietnam

Objective: To test the effects of dietary mannan oligosaccharides (MOS) on clownfish Amphiprion ocellaris (A. ocellaris). Methods: Six levels (0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 g/kg diet) of MOS were added to the basal diet (used as control diet) and fed clownfish A. ocellaris [total length (24.21 ± 0.16) mm] for 70 days. Growth performance and tissue protein were measured. Results: The result showed that growth rate was enhanced significantly in fish fed 0.10% and 0.15% MOS in diets compared to fish fed other MOS levels or control (P < 0.05). Survival rate significantly increased in fish fed diets with 0.20% and 0.25% MOS, compared to control. Fraction rates of protein growth were significantly higher in fish fed diets with 0.15%, 0.20%and 0.25% MOS supplementation than those fish fed other MOS inclusion levels and the control (P < 0.04). Dietary MOS concentrations and clownfish growth rates were significantly correlated. Optimal MOS concentration was predicted to be 0.185%, 0.173% and 0.171% at Days 14, 42 and 70, respectively. Conclusions: In conclusion, MOS-supplemented diet benefits for boosting growth, survival and body composition of the clownfish, A. ocellaris.

关键词： Amphiprion ocellaris Clownfish Mannan oligosaccharides Growth Body composition

Power Electronic Interface with Islanding Detection and Unbalanced Fault Ride-through Capability

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Journal of Energy and Power Engineering 2012年第11期6卷 1816-1825页

作者： nguyen Duc tuyen Goro Fujita Toshihisa Funabashi Masakatsu Nomurat Department of Electrical Engineering Shibaura Institute of Technology Tokyo 135-8548 Japan Solutions and Development Division Meidensha Corporation Tokyo 141-6029 Japan

Power electronic interface of dispersed generation plays a very important role in connecting a dispersed generation with utility grids. A power electronic interface not only adjusts the amount of active and reactive power injecting into a grid but also implements other importance duties as well. In this study, negative-sequence current injection has been fulfilled in three-phase power electronic interface for two important duties besides injecting reference power into utility grids. The first one is for islanding detection, and the other one is to enhance unbalance-fault ride-through capability of dispersed generation. This paper introduces a mechanism of negative-sequence injection based on controlling two separate coordinates of dq-control and explains the effect of negative-sequence injection in limiting the unbalanced currents generated from a dispersed generation. Using adaptive notch filter as a signal processing unit for the three-phase system, negative-sequence components are observed. The performance of entire control system is evaluated by time domain simulations, PSCAD/EMTDC （power systems computer aided design/electromagnetic transients including DC）.

关键词： Dispersed generation islanding detection negative-sequence components ride-through.

Stress relaxation analysis of single chondrocytes using porohyperelastic model based on AFM experiments

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Theoretical & Applied Mechanics Letters 2014年第5期4卷 74-80页

作者： trung Dung nguyen Adekunle Oloyede Yuantong Gu School of Chemistry Physics and Mechanical EngineeringScience and Engineering FacultyQueensland University of Technology

Based on atomic force microscopy technique, we found that the chon- drocytes exhibits stress relaxation behavior. We explored the mechanism of this stress relaxation behavior and concluded that the intracellular fluid exuding out from the cells during deformation plays the most important role in the stress relax- ation. We applied the inverse finite element analysis technique to determine nec- essary material parameters for porohyperelastic （PHE） model to simulate stress relaxation behavior as this model is proven capable of capturing the non-linear behavior and the fluid-solid interaction during the stress relaxation of the single chondrocytes. It is observed that PHE model can precisely capture the stress re- laxation behavior of single chondrocytes and would be a suitable model for cell biomechanics.

关键词： cell biomechanics chondrocytes atomic force microscopy stress relaxation,porohyperelastic (PHE) constitutive model

三角帆蚌在越南池塘和河道养殖生长发育及环境重要因子分析

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三角帆蚌在越南池塘和河道养殖生长发育及环境重要因子分析

作者： nguyen trung THANH 上海海洋大学

学位级别：硕士

本论文报道了不同养殖模式下三角帆蚌的生长发育及几个环境因子的研究结果。研究内容分为4部分:(1)池塘养殖条件下三角帆蚌生长情况和(2)河道养殖条件下三角帆蚌的生长情况;(3)三角帆蚌的性腺发育评价;(4)养殖水体浮游植物及水质因子分... 详细信息

本论文报道了不同养殖模式下三角帆蚌的生长发育及几个环境因子的研究结果。研究内容分为4部分:(1)池塘养殖条件下三角帆蚌生长情况和(2)河道养殖条件下三角帆蚌的生长情况;(3)三角帆蚌的性腺发育评价;(4)养殖水体浮游植物及水质因子分析。研究结果如下:三角帆蚌的整个生长周期,60至180日龄(秋季后期和冬季前期)壳长、壳宽、壳高是快速增长的阶段,180到270日龄出现增长延缓,180至270日龄(冬季后期和春季前期)是缓慢增长的阶段,尤其是210-240日龄(水温最低)是生长最慢的时间,270至330日龄(春季后期和夏季前期)由于水温逐渐增高所以生长逐渐增快。300至360日龄是增长最快的阶段。360至420日龄增长变慢。实验I(池塘)贝壳性状及体重高于实验II(河道)。池塘内(I)三角帆蚌90日龄三角帆蚌日增长率(ADG)达到最高为壳长0.548mm/日、壳高0.127mm/日、壳宽0.111mm/日,120日龄养殖时ADG为壳长0.388mm/日、壳高0.116mm/日、壳宽0.110mm/日,150日龄时壳长达到0.416mm/日、壳高0.103mm/日、壳宽0.218mm/日。河道内(II)三角帆蚌90日龄壳长、壳高、壳宽增长率分别为0.479mm/日,0.134mm/日,0.147mm/日。ADG结果表明了一个增长的趋势是壳长、壳高、壳宽增长速度最快在90至150日龄,然后ADG在180日龄至240日龄缓慢。池塘内(I)三角帆蚌60-90日龄壳长比生长率(SGR)达到最高(1.389±0.06%/日)和其它阶段差异有统计学意义(P0.05)。ADG最快点在150日龄时(池塘内的三角帆蚌达0.473±0,011(g/日),河道内的三角帆蚌达0.381±0.065(g/日))。150-180日龄日间体重增长速度减慢,池塘为0.059±0.022(g/日),河道为0.085±0.031(g/日)。210-240日龄增长速度更慢,池塘内的三角帆蚌为0.028±0.022(g/日),河道内的三角帆蚌为0.077±0.032(g/日)。240-270 I和II分别为0.412±0.024(g/日)和0.388±0.023(g/日)。三角帆蚌体重比增长速率(SGRw)在60-90日龄阶段达到最高,I和II分别为3.882%/日和4,668%/日。180-210日龄增长最慢,I和II分别为0,079%/日和0.998%/日。在全周期内平均SGRw I和II分别为1.410%/日和1.574%/日,差异没有统计学意义(P>0.05)。120-270日龄SGRw差异不明显(P>0.05)。池塘和河道水体的浮游植物组成十分丰富,包括大约8门,71种类。池塘内绿藻占优势;河道内硅藻占优势。池塘内特征的种类是Pediastrum sp。河道内叶绿素含量高于河道内,池塘内绿藻占78.3%,蓝藻占69.2%;河道内绿藻门占52.2%,蓝藻门占61.5%,河道内藻类主要是硅藻。池塘内的浮游植物量高于河道内,但多样性指数低于河道内。研究的水环境指标包括水温、p H值、透明度(SD)、溶解氧(DO)、盐度(S)、硬度(H)。水温研究时间池塘和河道平均范围分别在25.5 C-36.5 C和24 C-32.5 C。池塘水体的水温最高为36.5C(夏季后期和秋季前期),最低为25.5C(冬季后期和春季前期);河道内最高为32.5C,最低为24 C,二者均在三角帆蚌的适温范围内。平均透明度池塘高于河道(36.79厘米和33.42厘米)。池塘和河道的透明度都在理想范围(30-40厘米)。溶解氧(DO)在高范围内(池塘水体为4.5-6.5mg/l、河道水体为5.5-7mg/l),DO在11月份最低池塘水体为4.5mg/l,河道水体为5.5m

关键词：三角帆蚌生长发育浮游植物水质指标

基于刨煤机单刨刀截割试验的截割阻力模型研究

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煤炭科学技术 2016年第6期44卷 216-221页

作者：刘芮葭 Chu Viet Dung nguyen Viet tuyen 辽宁工程技术大学机械工程学院辽宁阜新123000

根据刨煤机刨刀截割煤岩阻力谱以及截割机理,辨识出刨头破碎煤岩的所受截割阻力,提出了基于单刨刀截割阻力、刨刀截割规律及运行参数来确定刨头瞬时截割阻力方法,建立刨头截割阻力试验-理论综合模型,给出了截割阻力模型算法。结果表明:... 详细信息

根据刨煤机刨刀截割煤岩阻力谱以及截割机理,辨识出刨头破碎煤岩的所受截割阻力,提出了基于单刨刀截割阻力、刨刀截割规律及运行参数来确定刨头瞬时截割阻力方法,建立刨头截割阻力试验-理论综合模型,给出了截割阻力模型算法。结果表明:当煤岩阻抗为225 N/cm、崩落角为30°、刨刀数量为14把时,刨头上的刨削阻力达到最大96.86 k N,变差系数达到最小0.509 53,载荷波动较小,有利于刨头刨削煤体,理论分析与试验结果基本吻合,截割阻力的特征和量值均有很好的复合度,单刨刀截割试验可反映出煤岩破碎的内在规律。

关键词：刨煤机刨刀截割载荷谱正交试验

Current Status of Sludge Collection, Transportation and Treatment in Ho Chi Minh City

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Journal of Environmental Protection 2013年第12期4卷 1329-1335页

作者： nguyen trung Viet Tran Thi My Dieu nguyen Thi Phuong Loan Department of Environmental Management and Technology Van Lang University Ho Chi Minh City Vietnam.

In the process of construction and development, Ho Chi Minh City is discharging about six types of sludge: 1) sludge from urban wastewater drainage systems;2) sludge from industrial wastewater drainage system;3) sludge from the canal dredging activities periodically;4) sludge from septic tanks;5) sludge from the water treatment station/plant;6) sludge from the construction sites. Sludge’s components are very different among types of sludge, sludge from the sewer network and canal dredging contain mainly sand and soil (70% - 90% dry weight), while the sludge from the wastewater/water treatment station/plant and from septic tanks contain mainly biodegradable organic substances (55% - 80% dry weight). The concentrations of all above-mentioned sludge (except sludge from the hazardous industrial wastewater treatment plant) are lower than toxic threshold. The volume of total sludge is about 3000 - 4000 m3/day (5000 - 6000 tons/day), excepting the amount of sludge generated from the water treatment plant (which is collected and treated separately). Sludge from wastewater treatment plants and septic tanks is collected, transported and recycled to become organic fertilizer. The other types of sludge are collected, transported, and disposed at the “unknown” locations, even though they have different values for use.

关键词： Sludge Sludge Collection Sludge Transportation Sludge Treatment Sludge Management

Hazardous metals emissions from e-waste-processing sites in a village in northern Vietnam

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Emerging Contaminants 2018年第1期4卷 11-21页

作者： Natsuyo Uchida Hidenori Matsukami Masayuki Someya nguyen Minh Tue Le Huu tuyen Pham Hung Viet Shin Takahashi Shinsuke Tanabe Go Suzuki Center for Material Cycles and Waste Management Research National Institute for Environmental Studies(NIES)16-2 OnogawaTsukubaIbaraki305-8506Japan Tokyo Metropolitan Research Institute for Environmental Protection 1-7-5 Shinsuna KotoTokyo136-0075Japan Center for Marine Environmental Studies(CMES) Ehime University2-5 Bunkyo-choMatsuyama790-8577Japan Center for Environmental Technology and Sustainable Development(CETASD) Hanoi University of Science334 Nguyen TraiHanoiViet Nam Center of Advanced Technology for the Environment Graduate School of AgricultureEhime University3-5-7 TarumiMatsuyama790-8566Japan

Inappropriate e-waste-processing operation is a serious issue in developing countries since the early 2000'*** research was conducted to clarify its influences and diffuse toxic substances in the environment at e-waste-processing sites in a village in northern Vietnam from 2012 to *** investigated surface soil samples collected from e-waste-processing sites,open burning sites,and rice paddy *** samples and water samples were also collected from a river that runs through the *** hazardous metal concentration in soil and river sediment samples indicated that 7 elements(Ca,Cu,Mo,Ni,Pb,Sn,and Zn)had high concentrations as a result of *** notably,Pb and Cu had high concentrations in soil samples(Pb:26e2200 mg/kg,Cu:22e3000 mg/kg).The results of a multivariate analysis indicated that these 7 elements were closely correlated with *** of hazardous metals showed an upward trend where e-waste-processing occurred during the 3-year study period,although it was not significant statistically at *** burning activity had a great influence on Cu accumulation,and maximum Cu concentrations increased from 340 mg/kg in 2012e3000 mg/kg in 2014 in soil samples from open-burning *** were large differences in the dominant hazardous metal depending on the type of e-waste-processing workshop because hazardous metal composition was influenced by the types of e-waste and the processing *** is necessary to avoid e-waste processing in open-air environment to control emissions of hazardous ***,open burning should be prohibited.

关键词： E-waste-processing Open burning Soil pollution Hazardous metal