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Assessment of early-age cracking of high-performance concrete in restrained ring specimens

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Water Science and Engineering 2010年第1期3卷 113-120页

作者： quang-phu nguyen Lin-hua JIANG Qiao ZHU College of Mechanics and Materials Hohai University Nanjing 210098 P R. China Faculty of Civil Engineering Water Resources University Hanoi Vietnam

High-performance concrete （HPC） is stronger and more durable than conventional concrete. However, shrinkage and shrinkage cracking are common phenomena in HPC, especially early-age cracking. This study assessed early-age cracking of HPC for two mixtures using restrained ring tests. The two mixtures were produced with water/binder mass ratio （mw/mB） of 0.22 and 0.40, respectively. The results show that, with greater steel thickness, the higher degree of restraint resulted in a higher interface pressure and earlier cracking. With steel thickness of 6 mm, 19 mm, and 30 mm, the age of cracking were, respectively, 12 days, 8 days, and 5.4 days with the mw/mB = 0.22 mixture; and 22.5 days, 12.6 days, and 7.1 days with the mw/mB= 0.40 mixture. Cases of the same steel thickness show that the ring specimens with a thicker concrete wall crack later. With the mw/mB = 0.22 mixture, concrete walls with thicknesses of 37.5 mm, 75 mm, and 112.5 mm cracked at 3.4 days, 8.0 days, and 9.8 days, respectively; with the mw/mB = 0.40 mixture, the ages of cracking were 7.1 days, 12.6 days, and 16.0 days, respectively.

关键词： high-performance concrete shrinkage early-age cracking restrained ring test

Analysis of an Ar plasma jet in a dielectric barrier discharge conjugated with a microsecond pulse

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Plasma Science and Technology 2019年第9期21卷 73-81页

作者： Duc Ba nguyen quang Hung TRINH Won Gyu LEE Young Sun MOK Department of Chemical and Biological Engineering Jeju National University Jeju 63243 Republic of Korea Center for Advanced Chemistry Institute of Research and Development Duy Tan University 03 Quang Trung Da Nang Vietnam Division of Chemical Engineering and Bioengineering Kangwon National University Chuncheon Kangwon 24341 Republic of Korea

In this work, an Ar plasma jet generated by an AC-microsecond-pulse-driven dielectric barrier discharge reactor, which had two ring-shaped electrodes isolated from the ambient atmosphere by transformer oil, was investigated. By special design of the oil insulation, a chemically active Ar plasma jet along with a safe and stable plasma process as well as low emission of CO and NOxwere successfully achieved. The results indicated that applied voltage and frequency were basic factors influencing the jet temperature, discharge power, and jet length, which increased significantly with the two operating parameters. Meanwhile, gas velocity affected the jet temperature in a reverse direction. In comparison with a He plasma jet, the Ar plasma jet had relatively low jet temperature under the same level of the input parameters, being preferable for bio-applications. The Ar plasma jet has been tested to interact with human skin within 5 min without the perception of burnt skin and electrical shock.

关键词： Ar plasma jet atmospheric pressure plasma jet OES of Ar gas emission of Ar plasma jet transformer oil

Electrochemical Immunosensor for Detection of Atrazine Based on Polyaniline/Graphene

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Journal of Materials Science & Technology 2016年第6期32卷 539-544页

作者： nguyen Van Chu nguyen Hai Binh Cao Thi Thanh nguyen Van Tu nguyen Le Huy nguyen Tuan Dzung Phan Ngoc Minh Vu Thi thu Tran Dai Lam Institute of Materials Science Vietnam Academy of Science and Technology18 Hoang Quoc VietCau Giay.HanoiViet Nam School of Chemical Engineering.Hanoi University of Science and Technology 1 Dai Co VietHanoiViet Ham Institute for Tropical Technology.Vietnam Academy of Science and Technology 18 Hoang Quoc VietHanoiViet Nam Center for High Technology Development Vietnam Academy of Science and Technology18 Hoang Quoc VietHanoiViet Nam University of Science and Technology of Hanoi.18 Hoang Quoc Viet HanoiViet Ham Graduate University of Science and Technology.Vietnam Academy of Science and Technology 18 Hoang Quoc Viet.HanoiViet Nam

In this study, a novel layer-by-layer polyaniline/graphene （PANi/Gr） structure for electrochemical detec- tion of atrazine was developed. Gr film was synthesized by thermal chemical vapor deposition （CVD） method and transferred onto the PANi-predeposited microelectrode. The properties of PANi/Gr film were thoroughly investigated by high-resolution transmission electron microscopy and Raman techniques. The most attractive feature of this system is a suitable microenvironment, which could provide an amplifi- cation of the conductive signal, thus may contribute to enhancing electron transfer and subsequently improve the sensitivity in electrochemical measurements. With low detection limit （- 43 × 10 -12 g/L）, ac-ceptable stability and good reproducibility, the proposed electrochemical immunosensor could be advantageously extended for multiplexed detection of other agents of environmental pollution.

关键词： Electrochemical immunosensor Polyaniline Graphene Atrazine

Emotion Recognition with Capsule Neural Network

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Computer Systems Science & Engineering 2022年第6期41卷 1083-1098页

作者： Loan Trinh Van quang H.nguyen thuy Dao Thi Le School of Information and Communication Technology Hanoi University of Science and TechnologyHanoi10000Vietnam Faculty of Information Technology University of Transport and CommunicationsHanoi10000Vietnam

For human-machine communication to be as effective as human-tohuman communication, research on speech emotion recognition is *** the models and the classifiers used to recognize emotions, neural networks appear to be promising due to the network’s ability to learn and the diversity in configuration. Following the convolutional neural network, a capsuleneural network (CapsNet) with inputs and outputs that are not scalar quantitiesbut vectors allows the network to determine the part-whole relationships thatare specific 6 for an object. This paper performs speech emotion recognition basedon CapsNet. The corpora for speech emotion recognition have been augmented byadding white noise and changing voices. The feature parameters of the recognition system input are mel spectrum images along with the characteristics of thesound source, vocal tract and prosody. For the German emotional corpus EMODB, the average accuracy score for 4 emotions, neutral, boredom, anger and happiness, is 99.69%. For Vietnamese emotional corpus BKEmo, this score is94.23% for 4 emotions, neutral, sadness, anger and happiness. The accuracy scoreis highest when combining all the above feature parameters, and this scoreincreases significantly when combining mel spectrum images with the featuresdirectly related to the fundamental frequency.

关键词： Emotion recognition CapsNet data augmentation mel spectrum image fundamental frequency

Emotional Vietnamese Speech Synthesis Using Style-Transfer Learning

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Computer Systems Science & Engineering 2023年第2期44卷 1263-1278页

作者： Thanh X.Le An T.Le quang H.nguyen School of Information and Communication Technology Hanoi University of Science and TechnologyHanoi10000Vietnam

In recent years,speech synthesis systems have allowed for the produc-tion of very high-quality ***,research in this domain is now turning to the problem of integrating emotions into ***,the method of con-structing a speech synthesizer for each emotion has some ***,this method often requires an emotional-speech data set with many *** data sets are very time-intensive and labor-intensive to ***,training each of these models requires computers with large computational capabilities and a lot of effort and time for model *** addition,each model for each emotion failed to take advantage of data sets of other *** this paper,we propose a new method to synthesize emotional speech in which the latent expressions of emotions are learned from a small data set of professional actors through a Flow-tron *** addition,we provide a new method to build a speech corpus that is scalable and whose quality is easy to ***,to produce a high-quality speech synthesis model,we used this data set to train the Tacotron 2 *** used it as a pre-trained model to train the Flowtron *** applied this method to synthesize Vietnamese speech with sadness and *** opi-nion score(MOS)assessment results show that MOS is 3.61 for sadness and 3.95 for *** conclusion,the proposed method proves to be more effec-tive for a high degree of automation and fast emotional sentence generation,using a small emotional-speech data set.

关键词： Emotional speech synthesis ﬂowtron speech synthesis style transfer vietnamese speech

Integrating Machine Learning and Evidential Reasoning for User Profiling and Recommendation

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Journal of Systems Science and Systems Engineering 2023年第4期32卷 393-412页

作者： Toan nguyen Mau quang-Hung Le Duc-Vinh Vo Duy Doan Van-Nam Huynh University of Information Technology Ho Chi Minh CityVietnam Vietnam National University Ho Chi Minh CityVietnam Department of Information Technology Quy Nhon UniversityQuy NhonVietnam Ho Chi Minh City University of Banking Ho Chi Minh CityVietnam School of Knowledge Science Japan Advanced Institute of Science and TechnologyIshikawaJapan

User profiles representing users’preferences and interests play an important role in many applications of personalized *** the rapid growth of social platforms,there is a critical need for efficient solutions to learn user profiles from the information they shared on social platforms so as to improve the quality of recommendation *** problem of user profile learning is significantly challenging due to difficulty in handling data from multiple sources,in different formats and often associated with *** this paper,we introduce an integrated approach that combines advanced Machine Learning techniques with evidential reasoning based on Dempster-Shafer theory of evidence for user profiling and *** developed methods for user profile learning and multi-criteria collaborative filtering are demonstrated with experimental results and analysis that show the effectiveness and practicality of the integrated approach.A proposal for extending multi-criteria recommendation systems by incorporating user profiles learned from different sources of data into the recommendation process so as to provide better recommendation capabilities is also highlighted.

关键词： Machine learning Dempster-Shafer theory of evidence user profiles personalized recommendation preferences

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

Anticancer effects of saponin and saponin–phospholipid complex of Panax notoginseng grown in Vietnam

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Asian Pacific Journal of Tropical Biomedicine 2016年第9期6卷 795-800页

作者： thu Dang Kim Hai nguyen Thanh Duong nguyen thuy Loi Vu Duc thu Vu Thi Hung Vu Manh Patcharee Boonsiri Tung Bui Thanh Department of Pharmacology and Clinical Pharmacy School of Medicine and PharmacyVietnam National University Department of Pharmaceutics and Pharmaceutical Technology School of Medicine and PharmacyVietnam National University Department of Pharmacology Hanoi University of Pharmacy Department of Pharmacognosy and Traditional Pharmacy School of Medicine and PharmacyVietnam National University Faculty of Biology VNU University of Science Key Laboratory of Enzyme and Protein Technology VNU University of Science Department of Pharmacology School of PharmacyLac Hong University Department of Biochemistry Faculty of MedicineKhon Kaen University

Objective:To evaluate the antitumor activity both in vitro and in vivo of saponin–phospholipid complex of Panax ***:The in vitro cytotoxic effect of saponins extract and saponin–phospholipid complex against human lung cancer NCI-H460 and breast cancer cell lines BT474 was examined using MTS *** in vivo evaluation of antitumor potential,saponin and saponin–phospholipid complex were administered orally in rats induced mammary carcinogenesis by 7,12-dimethylbenz(a)anthracene,for 30 ***:Our data showed that saponin–phospholipid complex had stronger anticancer effect compared to saponin *** IC50 values of saponin–phospholipid complex and saponin extract for NCI-H460 cell lines were 28.47 mg/m L and 47.97 mg/mL,respectively and these values for BT474 cells were 53.18 mg/mL and 86.24 mg/mL,*** vivo experiments,administration of saponin,saponin–phospholipid complex and paclitaxel(positive control) effectively suppressed 7,12-dimethylbenz(a) anthracene-induced breast cancer evidenced by a decrease in tumor volume,the reduction of lipid peroxidation level and increase in the body weight,and elevated the enzymatic antioxidant activities of superoxide dismutase,catalase,glutathione peroxidase in rat breast ***:Our study suggests that saponin extract from Panax notoginseng and saponin–phospholipid complex have potential to prevent cancer,especially breast cancer.

关键词： Panax notoginseng Saponin Saponin–phospholipid complex Breast cancer Antitumor

Mathematical modeling and numerical computation of the effective interfacial conditions for Stokes flow on an arbitrarily rough solid surface

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Applied Mathematics and Mechanics(English Edition) 2021年第5期42卷 721-746页

作者： A.T.TRAN H.LE quang Q.C.HE D.H.nguyen Research and Application Center for Technology in Civil Engineering University of Transport and CommunicationsHanoi 10000Vietnam Laboratoire Modelisation et Simulation Multi-Echelle Unite Mixte de Recherche 8208Centre National de la Recherche ScientifiqueUniversite Gustave EiffelMarne-la-Vallee F-77454France School of Mechanical Engineering Southwest Jiaotong UniversityChengdu 610031China

The present work is concerned with a two-dimensional(2D)Stokes flow through a channel bounded by two parallel solid *** distance between the walls may be arbitrary,and the surface of one of the walls can be arbitrarily *** main objective of this work consists in homogenizing the heterogeneous interface between the rough wall and fluid so as to obtain an equivalent smooth slippery fluid/solid interface characterized by an effective slip *** solve the corresponding problem,two efficient numerical approaches are elaborated on the basis of the method of fundamental solution(MFS)and the boundary element methods(BEMs).They are applied to different cases where the fluid/solid interface is periodically or randomly *** results obtained by the proposed two methods are compared with those given by the finite element method and some relevant ones reported in the *** comparison shows that the two proposed methods are particularly efficient and accurate.

关键词： effective slip length method of fundamental solution(MFS) boundary element method(BEM) Stokeslet micro-channel fluid/solid interface