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*** human visual cortex responses to flickering light using functional near infrared spectroscopy and constrained ICA

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Journal of Innovative Optical Health Sciences 2014年第6期7卷 77-89页

作者： nguyen duc Thang Vo Van Toi Le Giang Tran nguyen Huynh Minh Tam Lan Anh Trinh Biomedical Engineering Department International University Vietnam National Universities HCMCVietnam University of Saskatchewan Canada Electronics Engineering Department Posts and Telecommunications Institute of Technology Ho Chi Minh City Vietnam

The human visual sensitivity to the flickering light has been under investigation for *** finding of research in this area can contribute to the understanding of human visual system mechanism and visual disorders,and establishing diagnosis and treatment of *** aim of this study is to investigate the ffects of the flickering light to the visual cortex by monitoring the hemodynamic responses of the brain with the functional near infrared spectrosoopy(ENIRS)*** the acquired fNIRS signals are afected by physiological factors and measurement artifacts,constrained independent component analysis(eICA)was applied to extract the actual fNIRS responses from the obtained *** experimental results revealed significant changes(p<0.0001)of the hemodynamic responses of the visual *** the baseline when the flickering stimulation was *** the uses of cICA,the contrast to noise ratio(CNR),reflecting the contrast of hemodynamic concentration between rest and task,became *** indicated the improvement of the NIRS signals when the noise was *** subsequent studies,statistical analysis was used to infer the correlation between the NIRS signals and the visual *** found that there was a slight decrease of the oxygenated hemoglobin con-centration(about 5.69%)over four frequencies when the modulation ***,the variations of oxy and deoxy-hemoglobin were not statistically significant.

关键词： Papillometre visual stimulation functional near infrared spectroscopy constrained independent component analysis

Formability improvement and blank shape definition for deep drawing of cylindrical cup with complex curve profile from SPCC sheets using FEM

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Journal of Central South University 2014年第1期21卷 27-34页

作者： duc-Toan nguyen Duy-Khoe Dinh Hong-Minh Thi nguyen Tien-Long Banh Young-Suk Kim School of Mechanical Engineering Hanoi University of Science and Technology1A-Dai Co Viet StreetHai Ba Trung DistrictHanoi CityVietnam Department of Mechanical Engineering Hungyen University of Technology and EducationHungyenVietnam Department of Mechanical Engineering Kyungpook National University1370 SangyeokBuk-kuDaegu 702-701Korea

In the current work, to predict and improve the formability of deep drawing process for steel plate cold rolled commercial grade （SPCC） sheets, three parameters including the blanking force, the die and punch comer radius were considered. The experimental plan according to Taguchi＇s orthogonal array was coupled with the finite element method （FEM） simulations. Firstly, the data from the test of stress-strain and forming limit curves were used as input into ABAQUS/Explicit finite element code to predict the failure occurrence of deep drawing process. The three parameters were then validated to establish their effects on the press formability. The optimum case found via simulation was finally confirmed through an experiment. In order to obtain the complex curve profile of cup shape after deep drawing, the anisotropic behavior of earring phenomenon was modeled and implemented into FEM. After such phenomenon was correctly predicted, an error metric compared with design curve was then measured.

关键词： finite element method SPCC deep-drawing forming limit diagram criterion Taguchi's method earring prediction

Twin reversed arterial perfusion sequence-a rare and dangerous complication form of monochorionic twins:A case report

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World Journal of Clinical Cases 2022年第28期10卷 10214-10219页

作者： nguyen Duy Anh nguyen-Thi Thu Ha nguyen-Thi Sim nguyen Khac Toan Phan-Thi Huyen Thuong nguyen Minh duc Fetal Medicine Center Hanoi Obstetrics and Gynecology HospitalHanoi 100000Vietnam Department of Assisted Reproduction Hanoi Obstetrics and Gynecology HospitalHanoi 100000Vietnam Department of Obstetrics and Gynecology Hanoi University of Medicine and PharmacyHanoi 100000Vietnam Department of Radiology Pham Ngoc Thach University of MedicineHo Chi Minh City 700000Vietnam

BACKGROUND Twin reversed arterial perfusion(TRAP) sequence is an extremely rare congenital anomaly in monochorionic(MC) *** condition is characterized by a malformed fetus(acardiac twin) without cardiac activities being perfused by a structurally normal one(pump twin) via an artery-to-artery anastomosis in a reverse *** SUMMARY We described the first case of TRAP to receive laser surgery in *** 26-wk pregnancy was originally misdiagnosed in another hospital as MC twins with single intrauterine fetal *** admission to our center,the diagnosis was amended to a 26-wk TRAP sequence stage *** acardiac twin was 7.5 cm at the longest length,the ratio of the weight of the acardiac twin to the weight of the pump twin was more than 90%,the pump twin showed fetal distress with absent diastolic flow in umbilical artery of pump twin,and the peak systolic velocity in the middle cerebral artery = 1.6 Mo *** performed emergency laser photocoagulation of the acardiac twin’s umbilical *** surgery,we successfully maintained the pregnancy for 8 wk and ended it electively by cesarean section at 34 wk of gestation due to rupture of *** TRAP should be appropriately diagnosed and treated early to avoid complications of the pump *** laser photocoagulation is a new and effective treatment for this condition.

关键词： Twin reversed arterial perfusion Acardiac twin Pump twin Laser Case report

An Ontology-Based Question Answering System for University Admissions Advising

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Intelligent Automation & Soft Computing 2023年第4期36卷 601-616页

作者： Thi Thanh Sang nguyen dang Huu Trong Ho Ngoc Tram Anh nguyen School of Computer Science and Engineering International UniversityVNU-HCMCVietnam National UniversityHo Chi Minh CityVietnam

Question-Answer systems are now very popular and crucial to support human in automatically responding frequent questions in manyﬁ***,these systems depend on learning methods and training ***,it is necessary to prepare such a good dataset,but it is not an easy *** ontol-ogy-based domain knowledge base is able to help to reason semantic information and make effective answers given user *** study proposes a novel chatbot model involving ontology to generate efﬁcient responses automatically.A case study of admissions advising at the International University–VNU HCMC is taken into account in the proposed chatbot.A domain ontology is designed and built based on the domain knowledge of university admissions using Protégé.The Web user interface of the proposed chatbot system is developed as a prototype using *** includes a search engine reasoning the ontology and generat-ing answers to users’*** experiments are carried out to test how the system reacts to different ***ﬁrst experiment examines questions made from some templates,and the second one examines normal questions taken from frequent *** results have shown that the ontology-based chatbot can release meaningful and long *** results are analysed to prove the proposed chatbot is usable and promising.

关键词： Ontology chatbots answer-question systems domain knowledge base admissions advising

Spatial prediction of rainfall-induced shallow landslides using hybrid integration approach of Least-Squares Support Vector Machines and differential evolution optimization:a case study in Central Vietnam

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International Journal of Digital Earth 2016年第11期9卷 1077-1097页

作者： Dieu Tien Bui Binh Thai Pham Quoc Phi nguyen Nhat-duc Hoang Geographic Information System Group Department of Business Administration and Computer ScienceUniversity College of Southeast NorwayBøi TelemarkNorway Faculty of Geomatics and Land Administration Hanoi University of Mining and GeologyHanoiVietnam Department of Civil Engineering Gujarat Technological UniversityAhmedabadGujaratIndia Department of Geotechnical Engineering University of Transport TechnologyHa NoiVietNam Department of Environmental Sciences Hanoi University of Mining and GeologyHanoiVietnam Faculty of Civil Engineering Institute of Research and DevelopmentDuy Tan UniversityDanangVietnam

This study represents a hybrid intelligence approach based on the differential evolution optimization and Least-Squares Support Vector Machines for shallow landslide prediction,named as *** LSSVM is used to establish a landslide prediction model whereas the DE is adopted to search the optimal tuning parameters of the LSSVM *** this research,a GIS database with 129 historical landslide records in the Quy Hop area(Central Vietnam)has been collected to establish the hybrid *** receiver operating characteristic(ROC)curve and area under the curve(AUC)were used to assess the performance of the newly constructed *** results show that the proposed model has high performances with approximately 82%of AUCs on both training and validating *** model’s results were compared with those obtained from other methods,Support Vector Machines,Multilayer Perceptron Neural Networks,and J48 Decision *** result comparison demonstrates that the DE-LSSVMSLP deems best suited for the dataset at hand;therefore,the proposed model can be a promising tool for spatial prediction of rainfall-induced shallow landslides for the study area.

关键词： Shallow landslide Least-Squares Support Vector Machines differential evolution GIS Vietnam

Effects of low energy (160 keV) X-ray on microbial inactivation,sprouting inhibition and genetic variation in potato

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Food Bioscience 2022年第3期47卷 262-270页

作者： nguyen An Son nguyen Thi Nguyet Ha nguyen Thi Minh Sang Le Doan Dinh duc Le Ngoc Trieu Faculty of Physic and Nuclear Engineering Da Lat UniversityViet Nam Dalat Vocational Training College Viet Nam Faculty of Biology Da Lat UniversityViet Nam

The effects of low energy X-ray irradiation on microbial inactivation,sprouting inhibition and genetic variation were *** was an inverse correlation between the exposure dose in range of 0 Gy–5000 Gy and the survival rate of *** dose of 1000 Gy seemed to be suitable for inactivation of microorganisms because the respective survival rate is relatively low (0.59%).Dose rate of 13.87 Gy/min was the most appropriate to inactivate the microorganisms,with the survival rate of 0.37%.Applying the irradiation dose of 1000 Gy and dose rate of 13.87 Gy/min,there was a significant sprouting inhibition of irradiated potatoes compared to the control for six months *** effect of irradiation dose (100–1200 Gy) and dose rate (8.63–19.62 Gy/min) on genetic variation of the irradiated samples was assessed by DNA fingerprints induced from using three molecular techniques including Random Amplified Polymorphic DNA (RAPD),Start Codon Targeted Polymorphism (SCoT) and CAAT box – derived polymorphism (CBDP).At the irradiation dose of 1000 Gy and dose rate of 13.87 Gy/min,the level of genetic variation was relatively low (4.85%).Thus,this treatment is a suitable condition of irradiation for potato treatment with the purpose of preservation.

关键词： Dose Dose rate Low energy X-ray Microbial inactivation Potato

The effectiveness of light emitting diode(LED)lamps in the offshore purse seine fishery in Vietnam

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Aquaculture and Fisheries 2023年第5期8卷 551-557页

作者： nguyen dang Nhat Do Thanh Tien Truong Van Dan nguyen Duy Quynh Tram nguyen Quang Lich Ho dang Phuc nguyen Ngoc Phuoc School of Engineering and Technology Hue University01 Dien Bien PhuHue City52000Viet Nam Faculty of Engineering and Food Technology University of Agriculture and ForestryHue University102 Phung HungHue City52000Viet Nam Faculty of Fisheries University of Agriculture and ForestryHue University102 Phung HungHue City52000Viet Nam Institute of Mathematics Vietnam Academy of Science and Technology18 Hoang Quoc VietCau Giay DistrictHanoi11300Viet Nam

Fishing with artificial light has become one of the most advanced,efficient,and common methods for the night-time purse seining in *** study evaluated the radiation spectrum,CIE chromaticity coordinates,correlated color temperature(CCT),catch rate,fuel consumption,and CO_(2)emissions when using Light emitting diode(LED)lamps(0.196 kW)in comparison with the use of metal halide(MH)lights(1 kW)in the offshore purse seine fishery in Quang Tri province,*** fishing efficiency of the purse seine fishing boats using LED lamps has increased 1.58 times in catch rate than MH lights,although the energy consumption of LED lamp is 4 times *** consumption of boats per trip using LED lamps was one third of that using MH *** use of LED reduced the radiation spectrum,especially the intense UV radiation which negatively affects the health of *** study also showed the potential of CO_(2)emission reduction up to 1.09 tons of CO_(2)per trip per boat from the use of LED lamps in the offshore purse seine fishing boats.

关键词： Light emitting diode(LED)lamp Metal halide(MH)light Offshore purse seine fishery Quang tri province Vietnam

Hole and/or Electron Mediated Ferromagnetism in Diluted Magnetic Semiconductor？

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材料科学与工程（中英文B版） 2012年第4期2卷 317-323页

作者： dang duc Dung nguyen Thi Mua nguyen Van Quyet Sunglae Cho Department of General Physics School of Engineering Physics Ha Noi University of Science and Technology 1 Dai Co Viet roadHa Noi Viet Nam Department of Physics University of Ulsan Ulsan 690-749 Republic of Korea Hanoi Universitv of Prevention and Fizht Fire 243 Khuat Duv Tien Road Hanoi Vietnam School of Materials Science ＆ Engineering University of Ulsan Ulsan 680-749 Republic of Korea

The hole mediated ferromagnetism is well-known in Mn-doped group III-V, IV such as Ga1-xMnxAs, MnxGe1-x etc. So far, the magnetic ordered in this case of co-dopants is still unclear due to the strong limited from both experiment and theoretical prediction. The Curie temperature increase then saturation for increasing the hole concentration as rising p-type dopants concentration. However, Curie temperature slightly decreases then increase again as increase the n-type dopants concentration. In this work, the review of the effect of co-dopants on Mn-based DMSs was considered for both experiment and theoretical. The issues in case of co-doped have been presented in discussion. The finding the answers which way open the new class spintronic materials to develop applications.

关键词：自旋电子材料稀磁半导体铁磁性介导 Mn掺杂居里温度掺杂浓度理论预测

Xanthine oxidase inhibitors from Archidendron clypearia(Jack.) I.C. Nielsen: Results from systematic screening of Vietnamese medicinal plants

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Asian Pacific Journal of Tropical Medicine 2017年第6期10卷 619-626页

作者： nguyen Thuy Duong Pham duc Vinh Phuong Thien Thuong nguyen Thi Hoai Le nguyen Thanh Tran The Bach nguyen Hai Nam nguyen Hoang Anh Department of Pharmacology Hanoi University of Pharmacy Department of Pharmaceutical Analysis and Standardization National Institute of Medicinal Materials Department of Pharmacognosy Hue University of Medicine and Pharmacy Institute of Marine Biochemistry Vietnam Academy of Science and Technology Institute of Ecology and Biological Resources Vietnam Academy of Science and Technology Department of Medicinal Chemistry Hanoi University of Pharmacy

Objective: To screen Vietnamese medicinal plants for xanthine oxidase(XO) inhibitory activity and to isolate XO inhibitor(s) from the most active plant. Methods: The plants materials were extracted by methanol. The active plant materials were fractionated using different organic solvents, including n-hexane, ethyl acetate, and n-butanol. Bioassay-guided fractionation and column chromatography were used to isolate compounds. The compounds structures were elucidated by analysis of spectroscopic data, including IR, MS, and NMR. Results: Three hundreds and eleven methanol extracts(CME) belonging to 301 Vietnamese herbs were screened for XO inhibitory activity. Among these plants, 57 extracts displayed XO inhibitory activity at 100 μg/m L with inhibition rates of over 50%. The extracts of Archidendron clypearia, Smilax poilanei, Linociera ramiflora and Passiflora foetida exhibited the greatest potency with IC_(50) values below 30 μg/m L. Chemical study performed on the extract of Archidendron clypearia resulted in the isolation of six compounds, including 1-octacosanol, docosenoic acid, daucosterol, methyl gallate, quercitrin and(-)-7-O-galloyltricetiflavan. The compound(-)-7-O-galloyltricetiflavan showed the most potent XO inhibitory activity with an IC_(50) value of 25.5 μmol/L. Conclusions: From this investigation, four Vietnamese medicinal plants were identified to have XO inhibitory effects with IC_(50) values of the methanol extracts below 30 μg/m L. Compound(-)-7-O-galloyltricetiflavan was identified as an XO inhibitor from Archidendron clypearia with IC_(50) value of 25.5 μmol/L.

关键词： Xanthine oxidase Inhibitor Medicinal plants Vietnam