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Acta Mathematica Scientia 2022年第2期42卷 795-812页

作者： Nguyen Xuan LINH Duong Viet THONG Prasit CHOLAMJIAK Pham Anh TUAN luong van long Department of Mathematics Mathematics Falcuty of Information TechnologyNational University of Civil Engineering Division of Applied Mathematics Thu Dau Mot UniversityBinh Duong ProvinceVietnam School of Science University of PhayaoPhayao 56000Thailand Paculty of Mathematical Economics National Economics UniversityHanoi CityVietnam

In this work,we investigate a classical pseudomonotone and Lipschitz continuous variational inequality in the setting of Hilbert space,and present a projection-type approximation method for solving this *** method requires only to compute one projection onto the feasible set per iteration and without any linesearch procedure or additional projections as well as does not need to the prior knowledge of the Lipschitz constant and the sequentially weakly continuity of the variational inequality mapping.A strong convergence is established for the proposed method to a solution of a variational inequality problem under certain mild ***,we give some numerical experiments illustrating the performance of the proposed method for variational inequality problems.

关键词： Inertial method Tseng’s extragradient viscosity method variational inequality problem pseudomonotone mapping strong convergence

A Complex Fuzzy LSTM Network for Temporal-Related Forecasting Problems

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Computers, Materials & Continua 2024年第9期80卷 4173-4196页

作者： Nguyen Tho Thong Nguyen van Quyet Cu Nguyen Giap Nguyen long Giang luong Thi Hong Lan Institute of Information Technology Vietnam Academy of Science and TechnologyHoang Quoc VietCau GiayHanoi100000Vietnam Academic Affairs Department Thai Nguyen University of EducationThai Nguyen250000Vietnam Center of Science and Technology Research and Development Thuongmai UniversityHo Tung MauCau GiayHanoi100000Vietnam Faculty of Information Technology Hanoi University of IndustryBac Tu LiemHanoi100000Vietnam

Time-stamped data is fast and constantly growing and it contains significant information thanks to the quick development ofmanagement platforms and systems based on the Internet and cutting-edge information communication *** the time series data including time series prediction has many practical *** new techniques were developed for use with various types of time series data in the prediction *** those,this work suggests a unique strategy to enhance predicting quality on time-series datasets that the timecycle matters by fusing deep learning methods with fuzzy *** order to increase forecasting accuracy on such type of time-series data,this study proposes integrating deep learning approaches with fuzzy ***,it combines the long short-termmemory network with the complex fuzzy set theory to create an innovative complex fuzzy long short-term memory model(CFLSTM).The proposed model adds a meaningful representation of the time cycle element thanks to a complex fuzzy set to advance the deep learning long short-term memory(LSTM)technique to have greater power for processing time series *** on standard common data sets and real-world data sets published in the UCI Machine Learning Repository demonstrated the proposedmodel’s utility compared to other well-known forecasting *** results of the comparisons supported the applicability of our proposed strategy for forecasting time series data.

关键词： Complex fuzzy set long short-term memory(LSTM) CFLSTM T-CFLSTM

Application of extreme gradient boosting in predicting the viscoelastic characteristics of graphene oxide modified asphalt at medium and high temperatures

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Frontiers of Structural and Civil Engineering 2024年第6期18卷 899-917页

作者： Huong-Giang Thi HOANG Hai-van Thi MAI Hoang long NGUYEN Hai-Bang LY University of Transport Technology Hanoi 100000Vietnam

Complex modulus(G^(*))is one of the important criteria for asphalt classification according to AASHTO M320-10,and is often used to predict the linear viscoelastic behavior of asphalt *** addition,phase angle(φ)characterizes the deformation resilience of asphalt and is used to assess the ratio between the viscous and elastic *** is thus important to quickly and accurately estimate these two *** purpose of this investigation is to construct an extreme gradient boosting(XGB)model to predict G^(*)andφof graphene oxide(GO)modified asphaltat medium and high *** data sets are gathered from previously published experiments,consisting of 357 samples for G^(*)and 339 samples forφ,and the se are used to develop the XGB model using nine inputs representing theasphalt binder *** findings show that XGB is an excellent predictor of G^(*)andφof GO-modified asphalt,evaluated by the coefficient of determination R^(2)(R^(2)=0.990 and 0.9903 for G^(*)andφ,respectively)and root mean square error(RMSE=31.499 and 1.08 for G^(*)andφ,respectively).In addition,the model’s performance is compared with experimental results and five other machine learning(ML)models to highlight its *** the final step,the Shapley additive explanations(SHAP)value analysis is conducted to assess the impact of each input and the correlation between pairs of important features on asphalt’s two physical properties.

关键词： complex modulus phase angle graphene oxide asphalt extreme gradient boosting machine learning

The shear strength of the interface between artificial rock and printed concrete at super-early ages

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Frontiers of Structural and Civil Engineering 2024年第1期18卷 51-65页

作者： Yong Yuan Xiaoyun Wang Jiao-long Zhang Yaxin Tao Kim van Tittelboom Luc Taerwe Geert De Schutter College of Civil Engineering Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China Belgium-China Joint Laboratory for Industrialized Construction Tongji UniversityShanghai 200092China Magnel-vandepitte Laboratory for Structural Engineering and Building Materials Ghent UniversityGhent 9052Belgium

3D concrete printing has the potential to replace shotcrete for construction of linings of tunnels in hard *** shear strength of the interface between rock and printed concrete is vital,especially at super-early ***,traditional methods for testing the shear strength of the interface,e.g.,the direct shear test,are time-consuming and result in a high variability for fast-hardening printed *** this paper,a new fast bond shear test is *** test can be completed in 1 min,with another 2 min for preparing the next *** influence of the matrix composition,the age of the printed matrices,and the interface roughness of the artificial rock substrate on the shear strength of the interface was experimentally *** tests were conducted at the age of the matrices at the 1st,the 4th,the 8th,the 16th,the 32nd,and the 64th min after its final setting.A dimensionless formula was established to calculate the shear strength,accounting for the age of the printed matrices,the interface roughness,and the shear failure *** was validated by comparing the calculated results and the experimental results of one group of samples.

关键词： rock tunnel printed concrete interface fast bond shear test shear strength

Comparative Chemical Research in Essential Oils from Six Apiaceae Species Growing in the Northern Region of Vietnam

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1677-1687页

作者： Nguyen Quang Hung Nguyen Thanh Tung Nguyen Phuong Hanh Chu Thi Thu Ha Nguyen Thi Nhung Nguyen Thai An Vu Xuan Giang luong van Hao Oleh Koshovyi Ain Raal Institute of Ecology and Biological Resources Vietnam Academy of Science and Technology(VAST)Cau GiayHa Noi100000Viet Nam Graduate University of Science and Technology Vietnam Academy of Science and Technology(VAST)Cau GiayHa Noi100000Viet Nam Department of Pharmacognosy Faculty of Pharmacognosy and Traditional MedicineHanoi University of PharmacyHoan KiemHa Noi100000Viet Nam Sa Pa Research Center of Medicinal Materials National Institute of Medicinal MaterialsDien Bien PhuSa PaLao Cai330000Viet Nam Institute of Pharmacy Faculty of MedicineUniversity of TartuTartu50411Estonia

Our study aimed to compare the essential oil(EO)concentration and composition of several Apiaceae species growing in the Northern region of *** yields of EOs from materials ranged from 0.03%(root EO of Angelica acutiloba and aerial parts EO of Heracleum bivittatum)-0.27%(leaf EO of Xyloselinum vietnamense).Gas chromatography-mass spectrometry(GC-MS)allowed the identiﬁcation of 74 components in the EOs of six Apiaceae species,making up 94.4%–100.0%of the *** EO from Angelica acutiloba,(Z)-ligustilide accounted for an extremely large proportion(94.9%).EO of Angelica pubescens was dominated by six character-istic components includingα-pinene(21.5%),β-phellandrene(18.1%),p-cymene(12.2%),3-methylnonane(8.7%),o-cymene(8.1%),and D-sylvestrene(6.2%).The EO from Cryptotaenia japonica was characterized by high amounts ofα-selinene(48.7%),β-selinene(23.7%),and trans-β-farnesene(5.4%).The EOs from leaves and stems of Xyloselinum vietnamense were characterized by high concentrations of sabinene(69.8%and 33.8%),4-terpineol(8.7%and 7.4%)andβ-pinene(4.0%and 6.5%)while EOs from aerial parts and root of Xylo-selinum leonidii comprise four characteristic monoterpenes includingα-pinene(28.2%and 52.8%),β-pinene(7.9%and 10.3%),β-phellandrene(7.6%and 15.3%),and sabinene(3.0%and 4.1%).Additionally,cryptone is also one of the major components in the EO of Xyloselinum leonidii(13.2%in the aerial parts oil and 2.8%in the root oil).In the EOs isolated from the aerial parts and root of Heracleum bivittatum,α-pinene(22.5%and 70.2%)andβ-pinene(43.2%and 20.0%)were the predominant *** appeared in the EO from aerial parts of Heracleum bivittatum with a relatively high concentration(13.5%)while bornyl acetate(5.1%)was also one of the main components in the EO from its aerial parts but was not detected in other Apiaceae species in the present *** databases help identify and control the quality of plant material studied from the family Apiaceae growing in Vietnam.

关键词： Apiaceae essential oil terpenoids gaschromatography-mass spectrometry

Enhanced Grain Refining Effect of Mg–Zr Master Alloy on Magnesium Alloys via a Synergistic Strategy Involving Heterogeneous Nucleation and Solute‑Driven Growth Restriction

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1354-1366页

作者： Gang Zeng Hong Liu Jing‑Peng Xiong Jian‑long Li Yong Liu Key Laboratory of Lightweight and High Strength Structural Materials of Jiangxi Province School of Advanced ManufacturingNanchang UniversityNanchang 330031China

Zirconium(Zr)emerges as the most effective grain refiner for magnesium(Mg)alloys incorporating ***,Zr is introduced in the form of an Mg–Zr master ***,within Mg–Zr master alloys,Zr predominantly exists in a particle form,which tends to aggregate due to attractive van der Waals *** clustered Zr is prone to settling,thereby reducing its refining impact on Mg *** this work,a combined pretreatment process for Mg–Zr master alloys was proposed,encompassing the introduction of a physical field to intervene the agglomeration of particle Zr and the employ of high-temperature dissolution and peritectic reactions to promote the solid solution of *** results demonstrate that the particle Zr within the pretreated Mg–Zr master alloy is effectively dispersed and refined,and greater solute Zr levels can be *** subsequent grain refinement ability was studied on a typical Mg–6Zn–0.6Zr(wt%)*** outcome highlights that an improvement in the grain refinement efficacy(32.4%)of Mg–Zr master alloys was obtained with a holding time of 60 *** pretreated Mg–Zr master alloy significantly augments the efficiency of grain refinement for Mg alloys through a synergistic strategy involving heterogeneous nucleation and solute-driven growth *** crucial factor in achieving effective grain refinement of Zr in Mg alloys lies in regulating the presence and morphology of Zr in the Mg–Zr master alloy,distinguishing between particle Zr and solute *** study introduces a novel method for developing more efficient Mg–Zr refiners.

关键词： Magnesium alloy Mg-Zr master alloy Grain refinement Heterogeneous nucleation Solute-driven growth restriction Synergistic strategy

Thermodynamics of charged AdS black hole surrounded by quintessence in restricted phase space

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Chinese Physics B 2024年第10期33卷 205-212页

作者： Siyu Jian Siying long Juhua Chen Yongjiu Wang Department of Physics Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Educationand Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China

We study thermodynamics of charged AdS black hole surrounded by quintessence in a new formalism which is called the restricted phase space *** context is based on Visser’s holographic thermodynamics with a fixed antide Sitter radius and a variable Newton *** conjugate variables,central charge C and the chemical potential m,are introduced as a new pair of thermodynamic *** find that the iso-e-charge T-S curve becomes non-monotonic when Qvan der Waals-like phase *** the value of b related to the energy density of Kiselev’s fluid becomes larger,the critical temperature T_(c)will ***,the van derWaals-like phase transition will occur at lower *** is always a non-quilibrium transition from a small unstable black hole to a large stable black hole state in the isocoltage T-S *** exist a maximum and a Hawking-Page phase transition points in theμ-C *** the value of b related to Kiselev’s fluid becomes larger,the Hawking-Page phase transition will occur at lower temperature in the isovoltageμ-T *** other values of the state parameterω,there also exists van der Waals-like phase transition.

关键词： Reissner-Nordstrom qAdS black hole restricted phase space variable Newton constant

Exploring the Interplay between Job Stress,Work Performance,and Attitudes toward Professional Psychological Help among Employees

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International Journal of Mental Health Promotion 2024年第7期26卷 531-545页

作者： Cong Minh Le Son van Huynh Ky Luu Quynh-Nhi Ngoc Ho van Thi Le Nguyen Vinh-long Tran-Chi Center for Mental Health Research and Support University of Social Sciences and HumanitiesVietnam National University Ho Chi Minh CityHo Chi Minh City700000Vietnam Faculty of Psychology Ho Chi Minh City University of EducationHo Chi Minh City700000Vietnam Faculty of Tourism College of BusinessUniversity of Economics Ho Chi Minh CityHo Chi Minh City700000Vietnam Scientific Management Department Dong A UniversityDa Nang500000Vietnam

Objective:This study explores the interplay between job stress,job-related factors,work performance,and attitudes toward seeking professional psychological help among Vietnamese ***:A total of 374 employees in Vietnam were surveyed using random sampling and an online questionnaire from November 07 to November 28,*** data and self-reported from three scales:The New Job Stress Scale(NJSS),Work Performance(WP),and Attitudes Toward Seeking Professional Psychological Help(ATSPPH_SF)were ***:Significant variations were found across several variables,including forms of work,operating hours,education levels,monthly income,numbers of daily working hours,and the presence of a psychological counseling department within the *** analysis has highlighted direct relationships between key latent *** who were more open to seeking professional help tended to report higher levels of job *** negative relationship was found between job stress and attitudes toward seeking professional ***,work effort was positively associated with work *** analyses revealed the influence of co-worker support on role expectation conflict and work effort,role expectation conflict and work-life balance,as well as interactions between role expectation conflict and attitudes needed toward seeking professional *** analyses showed that work effort mediated relationships between openness to seeking professional help,co-worker support,work-life balance,role expectation conflict,and work *** toward seeking professional help also mediated relationships between work-life balance,job stress,and work ***:The study highlights the complex dynamics surrounding job stress,job-related factors,work performance,and attitudes toward seeking professional psychological help among Vietnamese *** highlights the importance of addressing help-seeking barriers,promoting work engagement

关键词： Stress co-worker support work-life balance role expectation conﬂict professional psychological help-seeking

Two-Dimensional Materials for Highly Efficient and Stable Perovskite Solar Cells

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Nano-Micro Letters 2024年第10期16卷 176-212页

作者： Xiangqian Shen Xuesong Lin Yong Peng Yiqiang Zhang Fei long Qifeng Han Yanbo Wang Liyuan Han State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong UniversityShanghai 200240People's Republic of China Xinjiang Key Laboratory of Solid State Physics and Devices School of Physical Science and TechnologyXinjiang UniversityUrumqi 830046People's Republic of China Special Division of Environmental and Energy Science College of Arts and SciencesKomaba Organization for Educational ExcellenceUniversity of TokyoTokyo 153-8902Japan State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070People's Republic of China College of Chemistry Henan Institute of Advanced TechnologyZhengzhou UniversityZhengzhou 450001People's Republic of China Guangxi Key Laboratory of Optical and Electronic Materials and Devices Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of ResourcesSchool of Materials Science and EngineeringGuilin University of TechnologyGuilin 541004People's Republic of China

Perovskite solar cells(PSCs)offer low costs and high power conversion ***,the lack of long-term stability,primarily stemming from the interfacial defects and the sus-ceptible metal electrodes,hinders their practical *** the past few years,two-dimensional(2D)materials(e.g.,graphene and its derivatives,transitional metal dichalcogenides,MXenes,and black phosphorus)have been identified as a promising solution to solving these problems because of their dangling bond-free surfaces,layer-dependent electronic band structures,tunable functional groups,and inherent ***,recent progress of 2D material toward efficient and stable PSCs is summarized,including its role as both interface materials and *** discuss their beneficial effects on perovskite growth,energy level alignment,defect passivation,as well as blocking external *** particular,the unique properties of 2D materials to form van der Waals heterojunction at the bottom interface are ***,perspectives on the further development of PSCs using 2D materials are provided,such as designing high-quality van der Waals heterojunction,enhancing the uniformity and coverage of 2D nanosheets,and developing new 2D materials-based electrodes.

关键词： Perovskite solar cells Two-dimensional materials Interface engineering van der Waals heterojunction Electrodes

Effects of ENSO and Climate Change on Reference Evapotranspiration in Southern Vietnam

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Journal of Meteorological Research 2021年第5期35卷 868-881页

作者： van Viet luong Industrial University of Ho Chi Minh City Ho Chi Minh City 71408Vietnam

This study aims to evaluate the effects of climate change and El Nino-Southern Oscillation(ENSO)on reference evapotranspiration(ET_(o))in the climate sub-regions of South Vietnam(SVN)and the role of the related meteorological *** trend analysis shows that ET_(o) has been increasing quite clearly,especially during the rainy *** examining the contribution of meteorological variables to the increase of ET_(o),it is indicated that temperature is the main *** the meteorological variables that are related to ET_(o),temperature is also the factor that has gained the most significant *** of variance reveals that there is no difference in the increase of ET_(o) among the climate sub-regions of *** effect of ENSO on ET_(o) is assessed based on the difference in the mean value of ET_(o) between the El Nino and La Nina *** results show that this difference is most obvious from October to May,and the main factor contributing to the increase is not temperature but sunshine *** difference in sunshine hours between the warm and cold phases in these months is around one hour per day,contributing about58%-86%to the ET_(o) *** analysis of variance shows that ENSO has different levels of influences on ET_(o) in the climate *** to the increase in ET_(o) due to climate change over the past 40 years,the ET_(o) difference between El Nino and La Nina phases is many times *** addition,since the effect of ENSO on ET_(o) is most obvious in the study area during the dry season,it is much *** order to mitigate the effect of ENSO on drought in this area,monitoring and forecasting meteorological variables that have the main contribution to the variation of ET_(o),including the number of sunshine hours,should be promoted.

关键词： climate change climate variability El Nino-Southern Oscillation(ENSO) reference evapotranspiration trend analysis sensitivity analysis