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Blockchain for Education:Verification and Management of Lifelong Learning Data

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Computer Systems Science & Engineering 2022年第11期43卷 591-604页

作者： ba-Lam Do Van-thanh Nguyen Hoang-Nam Dinh thanh-chung Dao BinhMinh Nguyen School of Information and Communication Technology Hanoi University of Science and TechnologyHanoiVietnam

In recent years,blockchain technology has been applied in the educational domain because of its salient advantages,i.e.,transparency,decentralization,and *** systems typically use public blockchain networks such as Ethereum and Bitcoin to store learning ***,the cost of writing data on these networks is significant,making educational institutions limit data sent to the target network,typically containing only hash codes of the issued *** this paper,we present a system based on a private blockchain network for lifelong learning data authentication and management named B4E(Blockchain For Education).B4E stores not only certificates but also learners’training data such as transcripts and educational programs in order to create a complete record of the lifelong education of each user and verify certificates that they have *** a result,B4E can address two types of fake certificates,i.e.,certificates printed by unlawful organizations and certificates issued by educational institutions for learners who have not met the training *** addition,B4E is designed to allow all participants to easily deploy software packages to manage,share,and check stored information without depending on a single point of *** such,the system enhances the transparency and reliability of the stored *** experiments show that B4E meets expectations for deployment in reality.

关键词： Training data certificate verification and management private blockchain

Optical Anisotropy in van der Waals materials: Impact on Direct Excitation of Plasmons and Photons by Quantum Tunneling

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Light(Science & Applications) 2021年第12期10卷 2387-2398页

作者： Zhe Wang Vijith Kalathingal thanh Xuan Hoang Hong-Son chu Christian A.Nijhuis Department of Chemistry National University of Singapore3 Science Drive 3Singapore 117543Singapore Centre for Advanced 2D Materials National University of Singapore6 Science Drive 2Singapore 117564Singapore Department of Electrical and Computer Engineering National University of Singapore4 Engineering Drive 3Singapore 117583Singapore Department of Electronics and Photonics Institute of High Performance ComputingA*STAR(Agency for ScienceTechnology and Research)1 Fusionopolis WaySingapore 138632Singapore Hybrid Materials for Opto-Electronics Group Department of Molecules and MaterialsMESA+Institute for Nanotechnology and Center for Brain-Inspired Nano SystemsFaculty of Science and TechnologyUniversity of Twente7500 AE EnschedeThe Netherlands

Inelastic quantum mechanical tunneling of electrons across plasmonic tunnel junctions can lead to surface plasmon polariton(SPP)and photon *** far,the optical properties of such junctions have been controlled by changing the shape,or the type of the material,of the electrodes,primarily with the aim to improve SPP or photon emission *** we show that by tuning the tunneling barrier itself,the efficiency of the inelastic tunneling rates can be improved by a factor of *** exploit the anisotropic nature of hexagonal boron nitride(hBN)as the tunneling barrier material in Au//hBN//graphene tunnel junctions where the Au electrode also serves as a plasmonic strip *** this junction constitutes an optically transparent hBN–graphene heterostructure on a glass substrate,it forms an open plasmonic system where the SPPs are directly coupled to the dedicated strip waveguide and photons outcouple to the far *** experimentally and analytically show that the photon emission rate per tunneling electron is significantly improved(~×3)in Au//hBN//graphene tunnel junction due to the enhancement in the local density of optical states(LDOS)arising from the hBN *** the dedicated strip waveguide,SPP outcoupling efficiency is quantified and is found to be∼80%stronger than the radiative outcoupling in Au//hBN//graphene due to the high LDOS of the SPP decay channel associated with the inelastic *** new insights elucidated here deepen our understanding of plasmonic tunnel junctions beyond the isotropic models with enhanced LDOS.

关键词： tunneling strip coupling

Cimicifuga heracleifolia is therapeutically similar to black cohosh in relieving menopausal symptoms: evidence from pharmacological and metabolomics studies

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Chinese Journal of Natural Medicines 2019年第6期17卷 435-445页

作者： MIAO Lan-Yun chu Thi thanh Huyen LI Ping JIANG Yan LI Hui-Jun State Key Laboratory of Natural Medicines China Pharmaceutical UniversityNanjing 210009China College of Chemical Engineering Nanjing Forestry UniversityNanjing 210037China

In the market of botanical dietary supplements, Cimicifuga heracleifolia(CH) has always been considered as an adulterated species of Cimicifuga racemosa(CR), a conventional American herb with promising benefits to counteract troubles arising from the menopause. However, the detailed comparison of their therapeutic effects is lacking. In present study, the pharmacological and metabolomics studies were comparatively conducted between CH and CR in ovariectomized(OVX) female rats. Specifically, estrogen-like, anti-hyperlipidemia and anti-osteoporosis effects were evaluated through measuring serum biochemical parameters, histopathological examination and micro computed tomography(Micro-CT) scanning. At the same time, a gas chromatography-mass spectrometry(GC-MS)-based serum metabolomics method was employed to profile the metabolite compositional changes. As a result, both CR and CH displayed anti-osteoporosis and anti-hyperlipemia on menopause syndrome. Meanwhile, their potentials in improving the OVX-induced metabolic disorders were discovered. In conclusion, these results demonstrated that CH is therapeutically similar to CR in relieving menopausal symptoms and CH could be considered as a promising alternative to CR instead of an adulterant in the market of botanical dietary supplements.

关键词： Cimicifuga heracleifolia Black cohosh Menopausal symptoms Metabolomics Substitute

Synthesis of cation exchange resin-supported iron and magnesium oxides/hydroxides composite for nitrate removal in water

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Chinese Journal of Chemical Engineering 2021年第4期34卷 378-384页

作者： Trung thanh Nguyen Vu Anh Khoa Tran Le ba Tran Phuoc Toan Phan Minh Tan Nguyen Long Giang bach Surapol Padungthon Cong Khiem Ta Nhat Huy Nguyen Nanomaterial Laboratory An Giang University18 Ung Van Khiem St.Dong Xuyen DistLong Xuyen CityAn Giang ProvinceViet Nam Vietnam National University Ho Chi Minh City Linh Trung WardThu Duc DistrictHo Chi Minh CityViet Nam Faculty of Natural Resources and Environment Ho Chi Minh City University of Technology(HCMUT)268 Ly Thuong Kiet St.Dist.10Ho Chi Minh CityViet Nam Faculty of Engineering-Technology-Environment An Giang University18 Ung Van Khiem StDong Xuyen DistLong Xuyen CityAn Giang ProvinceViet Nam Department of Scientific Research and International Relation Bac Lieu University178 Vo Thi Sau St.Ward 8Bac Lieu CityBac Lieu ProvinceViet Nam NTT Institute of High Technology Nguyen Tat Thanh University298-300A Nguyen Tat ThanhHo Chi Minh CityViet Nam Department of Environmental Engineering Khon Kaen University123 Moo 16 Mittraphap Rd.Nai-MuangMuang DistrictKhon Kaen 40002Thailand

In this study,we reported on the concept and practical use of cation exchange resin(CER)for removing anions in water via pretreating the CER with metal *** cation exchange resinsupported iron and magnesium oxides/hydroxides composite(FeMg/CER)was synthesized and introduced as a new and potential adsorbent for selective removal of nitrate ion in the water *** of FeMg/CER were determined by techniques such as Fouriertransform infrared spectroscopy,scanning electron microscopy,and Xray *** results showed that FeMg/CER material had a high nitrate adsorption capacity of 200 mg NO_(3)^()·g^(1)with a fast equilibrium adsorption time of 30 min at pH *** addition,it had good durability of at least 10 times of regeneration,which could be applied to practical water and wastewater treatment.

关键词： Iron oxide/hydroxide Magnesium oxide/hydroxide Cation exchange resin Adsorption Environment Nanomaterials

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

Small-Scale Household Biogas Digesters as a Viable Option for Energy Recovery and Global Warming Mitigation--Vietnam Case Study

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Journal of Agricultural Science and Technology(A) 2015年第6期5卷 387-395页

作者： thanh ba Ho Timothy Kilgour Roberts Steven Lucas Faculty of Environment and Natural Resources Nong Lain University Ho Chi Minh City Vietnam The Tom Farrell Institute for the Environment University of Newcastle NSW 2308 Australia

Biogas from livestock waste is considered as clean and renewable energy in Vietnam. In the last 20 years, in rural and remote areas of Vietnam, there has been a significant increase of small-scale household biogas digesters. Biogas digesters create the benefits of replacing energy and mitigation of climate change caused by greenhouse gas （GHG） emission and deforestation for firewood and charcoal. Livestock waste produces approximately 85 million tonnes every year and continues to increase, meaning there are huge feedstocks for biogas digesters to meet the energy demands in households. However, there are also many constraints on the development programme for small-scale household biogas digester. In Vietnam, the socio-economic situation and the lack of a sustainable energy policy for biogas from livestock sector are hindering the growth of the biogas digester industry. Government subsidies are needed to encourage farmers to participate. This paper will be helpful not only for the sustainable development of household biogas in Vietnam, but also for the developing program of biogas generation in developing countries with similar agricultural economies to Vietnam.

关键词： Small-scale household biogas renewable energy biogas digester Vietnam.

Hepatitis B vaccination status and associated factors among health science students

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Asian Pacific Journal of Tropical Medicine 2023年第5期16卷 213-219页

作者： Binh thanh Nguyen Lan Y Vo Tap Van Nguyen Minh Cong Vo Tinh Dang Pham Han Thi Ngoc Nguyen Lynda Boyer-chu Giao Huynh Faculty of Medicine Tra Vinh UniversityTra Vinh CityTra Vinh ProvinceVietnam Faculty of Public Health University of Medicine and Pharmacy at Ho Chi Minh CityHo Chi Minh CityVietnam Faculty of Medical Management Nguyen Tat Thanh UniversityHo Chi Minh CityVietnam Department of Ear Nose Throat-Head and Neck Surgery FV hospitalHo Chi Minh CityVietnam Department of Anaesthesia and Intensive Care FV hospitalHo Chi Minh CityVietnam Infection Control Department University Medical Center Ho Chi Minh CityHo Chi Minh CityVietnam San Francisco Unified School District San FranciscoCaliforniaUSA

Objective:To evaluate hepatitis B virus(HBV)vaccine coverage and its associated factors among health science students in ***:This cross-sectional study involving 459 health science students at Tra Vinh University was conducted between April and June *** were collected using a structured questionnaire with items on sociodemographic characteristics,knowledge and attitude about HBV,and vaccination status.A multivariable logistic regression model was used to explore the factors associated with vaccination ***:The majority of participants were female(65.8%)and enrolled at the medical school(56.2%).A total of 30.3%participants received the full dose of the HBV *** percentages of participants with sufficient knowledge and positive attitudes toward HBV infection were 75.2%and 43.4%,*** was 11.8 times higher in sixth-year medical students than any healthcare student in their first-year[adjusted odds ratio(aOR)11.8,95%CI 3.1-45.1,P<0.001],and the coverage was also significant higher in those who had sufficient knowledge(aOR 2.0,95%CI 1.1-3.9,P<0.05)and positive attitudes(aOR 3.0,95%CI 1.9-4.8,P<0.05)than in their ***:The majority of students were not fully vaccinated against HBV,indicating they were vulnerable to the *** and authorities should reinforce health education messages aimed at encouraging all students to get vaccinated with the HBV vaccine,enhance their awareness and knowledge of HBV,and improve attitudes toward HBV infection prevention.

关键词： Hepatitis B Knowledge Attitude Practice Vaccination Students

A New Method Combining Interior and Exterior Approaches for Linear Programming

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Journal of Mathematics and System Science 2015年第5期5卷 196-206页

作者： Nguyen Ngoc chu Pham Canh Duong Le thanh Hue Institute of Mathematics 18 Hoang Quoc Viet HanoL Vietnam. Center for Information Infrastructure Development Vietnamese Academy of Science and Technology 18 Hoang Quoc Viet HanoiVietnam. Faculty of lnformatics Technology University of Mining and Geology Hanoi Vietnam.

In this paper we present a new method combining interior and exterior approaches to solve linear programming problems. With the assumption that a feasible interior solution to the input system is known, this algorithm uses it and appropriate constraints of the system to construct a sequence of the so called station cones whose vertices tend very fast to the solution to be found. The computational experiments show that the number of iterations of the new algorithm is significantly smaller than that of the second phase of the simplex method. Additionally, when the number of variables and constraints of the problem increase, the number of iterations of the new algorithm increase in a slower manner than that of the simplex method.

关键词： Linear programming simplex method station cone.

High‐sensitivity distributed dynamic strain sensing by combining Rayleigh and Brillouin scattering

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Opto-Electronic Advances 2020年第12期3卷 1-8页

作者： Benzhang Wang Dexin ba Qi chu Liqiang Qiu Dengwang Zhou Yongkang Dong National Key Laboratory of Science and Technology on Tunable Laser Harbin Institute of TechnologyHarbin 150001China

The phase-sensitive optical time-domain reflectometry(φ-OTDR)is a good candidate for distributed dynamic strain sensing,due to its high sensitivity and fast measurement,which has already been widely used in intrusion monitoring,geophysical exploration,*** the frequency scanning basedφ-OTDR,the phase change manifests itself as a shift of the intensity *** correlation between the reference and measured spectra is employed for relative strain demodulation,which has imposed the continuous measurement for the absolute strain ***,the Brillouin optical time domain analysis(BOTDA)allows for the absolute strain demodulation with only one *** this work,the combination of theφ-OTDR and BOTDA has been proposed and demonstrated by using the same set of frequency-scanning optical pulses,and the frequency-agile technique is also introduced for fast measurements.A 9.9 Hz vibration with a strain range of 500 nεhas been measured under two different absolute strains(296.7μεand 554.8με)by integrating the Rayleigh and Brillouin *** sub-micro strain vibration is demonstrated by theφ-OTDR signal with a high sensitivity of 6.8 nε,while the absolute strain is measured by the BOTDA signal with an accuracy of 5.4με.The proposed sensor allows for dynamic absolute strain measurements with a high sensitivity,thus opening a door for new possibilities which are yet to be explored.

关键词： fiber optics sensor Rayleigh scattering Brillouin scattering fast measurement