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Prediction of Shear Bond Strength of Asphalt Concrete Pavement Using Machine learning Models and Grid Search Optimization Technique

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 691-712页

作者： Quynh-Anh Thi Bui Dam Duc Nguyen Hiep van le Indra Prakash Binh Thai Pham Civil Engineering Department University of Transport Technology54 Trieu KhucThanh XuanHanoi100000Vietnam DDG(R)Geological Survey of India Gandhinagar382010India

Determination of Shear Bond strength(SBS)at interlayer of double-layer asphalt concrete is crucial in flexible pavement *** study used three Machine learning(ML)models,including K-Nearest Neighbors(KNN),Extra Trees(ET),and Light Gradient Boosting Machine(LGBM),to predict SBS based on easily determinable input ***,the Grid Search technique was employed for hyper-parameter tuning of the ML models,and cross-validation and learning curve analysis were used for training the *** models were built on a database of 240 experimental results and three input variables:temperature,normal pressure,and tack coat *** validation was performed using three statistical criteria:the coefficient of determination(R2),the Root Mean Square Error(RMSE),and the mean absolute error(MAE).Additionally,SHAP analysis was also used to validate the importance of the input variables in the prediction of the *** show that these models accurately predict SBS,with LGBM providing outstanding ***(Shapley Additive explanation)analysis for LGBM indicates that temperature is the most influential factor on ***,the proposed ML models can quickly and accurately predict SBS between two layers of asphalt concrete,serving practical applications in flexible pavement structure design.

关键词： Shear bond asphalt pavement grid search optimization machine learning

Finite element analysis of functionally graded sandwich plates with porosity via a new hyperbolic shear deformation theory

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Defence Technology（防务技术） 2022年第3期18卷 490-508页

作者： Pham van Vinh le Quang Huy Department of Solid Mechanics Le Quy Don Technical University236 Hoang Quoc VietHanoiViet Nam Institute of Techniques for Special Engineering Le Quy Don Technical University236 Hoang Quoc VietHanoiViet Nam

This study focusses on establishing the finite element model based on a new hyperbolic sheareformation theory to investigate the static bending,free vibration,and buckling of the functionally graded sandwich plates with *** novel sandwich plate consists of one homogenous ceramic core and two different functionally graded face sheets which can be widely applied in many fields of engineering and defence *** discrete governing equations of motion are carried out via Hamilton’s principle and finite element *** computation program is coded in MATLAB software and used to study the mechanical behavior of the functionally graded sandwich plate with *** present finite element algorithm can be employed to study the plates with arbitrary shape and boundary *** obtained results are compared with available results in the literature to confirm the reliability of the present ***,a comprehensive investigation of the effects of several parameters on the bending,free vibration,and buckling response of functionally graded sandwich plates is *** numerical results shows that the distribution of porosity plays significant role on the mechanical behavior of the functionally graded sandwich plates。

关键词： Functionally graded sandwich plates Porous plates Hyperbolic shear deformation theory Bending analysis Free vibration analysis Buckling analysis

An analytical model for cross-Kerr nonlinearity in a four-level N-type atomic system with Doppler broadening

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Chinese Physics B 2022年第2期31卷 314-319页

作者： Dinh Xuan Khoa Nguyen Huy Bang Nguyen le Thuy An Nguyen van Phu le van Doai Vinh University 182 Le Duan StreetVinh CityVietna

We present an analytical model for cross-Kerr nonlinear coefficient in a four-level N-type atomic medium under Doppler *** model is applied to87 Rb atoms to analyze the dependence of the cross-Kerr nonlinear coefficient on the external light field and the temperature of atomic *** analysis shows that in the absence of electromagnetically induced transparency(EIT)the cross-Kerr nonlinear coefficient is zero,but it is significantly enhanced when the EIT is *** means that the cross-Kerr effect can be turned on/off when the external light field is on or ***,the amplitude and the sign of the cross-Kerr nonlinear coefficient are easily changed according to the intensity and frequency of the external light *** amplitude of the cross-Kerr nonlinear coefficient remarkably decreases when the temperature of atomic medium *** analytical model can be convenient to fit experimental observations and applied to photonic devices.

关键词： electromagnetically induced transparency Kerr nonlinear effect Doppler effect

Behavior of noncircular tunnels excavated in stratified rock masses-Case of underground coal mines

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第1期11卷 99-110页

作者： Ngoc Anh Do Daniel Dias van Diep Dinh Tien Tung Tran van canh Dao Viet Doan Dao Phuc Nhan Nguyen Department of Underground and Mining Construction.Faculty of Civil Engineering Hanoi University of Mining and Ceology School of Automotive and Transportation Engineering Hefei University of Technology Laboratory 35R Crenoble Alpes University

The amount of tunnels excavated along stratified/sedimentary rock masses in Quangninh coal mine area,Vietnam, is gradually increasing. Rock mass in Quangninh is characterized by beddings between rock layers. The behavior of stratified rock masses surrounding the tunnels depends on both the intact rock and the beddings between rock layers. The main characteristics of stratified rock masses that need to be considered are their heterogeneity and anisotropy. Depending on the dip angle of rock layers, movements and failure zones developed surrounding the tunnels can be asymmetrical over the vertical axis of tunnel. This asymmetry causes adverse behaviors of the tunnel structures. The objective of this study is to highlight convergences and yielded zones developed in rock masses surrounding noncircular tunnels in Quangninh coal mine area using a finite element method. The presence of bedding joints is explicitly simulated. The numerical results indicated that with the increase in dip angle of bedding joints, the stress asymmetry over the tunnel vertical axis increases. It gradually leads to an asymmetry of the failure zone surrounding the tunnel. An increase of rock mass quality means a decrease of rock mass sensitivity to the discontinuities. In addition,a dip angle of the bedding joints of approximately 45° could be considered as the critical angle at which the rock mass mechanism changes between sliding and bending.

关键词： Tunnel Bedding Stratification Anisotropic Heterogeneity

Some Strong Laws of Large Numbers for Blockwise Martingale Difference Sequences in Martingale Type p Banach Spaces

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Acta Mathematica Sinica,English Series 2012年第7期28卷 1385-1400页

作者： Andrew ROSALSKY le van THANH Department of Statistics University of Florida Department of Mathematics Vinh University

For a blockwise martingale difference sequence of random elements {Vn, n ≥ 1} taking values in a real separable martingale type p （1 ≤ p ≤ 2） Banach space, conditions are provided for strong laws of large numbers of the form limn→∞ Vi/gn = 0 almost surely to hold where the constants gn ↑∞. A result of Hall and Heyde [Martingale Limit Theory and Its Application, Academic Press, New York, 1980, p. 36] which was obtained for sequences of random variables is extended to a martingale type p （1〈 p ≤2） Banach space setting and to hold with a Marcinkiewicz-Zygmund type normalization. Illustrative examples and counterexamples are provided.

关键词： Sequence of Banach space valued random elements blockwise martingale difference sequence strong law of large numbers almost sure convergence martingale type p Banach space

LiMn_2O_4/CNTs and LiNi_(0.5)Mn_(1.5)O_4/CNTs Nanocomposites as High-Performance Cathode Materials for Lithium-Ion Batteries

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Acta Metallurgica Sinica(English letters) 2015年第1期28卷 122-128页

作者： Thang van le Ha Tran Nguyen Anh Tuan Luu Man van Tran Phung Loan My le Faculty of Materials Technology Ho Chi Minh University of Technology 268 Ly Thuong Kiet Ward 14 District 10 Ho Chi Minh City Vietnam Department of Physical Chemistry University of Science VNUHCM 227 Nguyen Van Cu Street District 5 Ho Chi Minh CityVietnam

The demand of higher energy density and higher power capacity of lithium（Li）-ion secondary batteries has led to the search for electrode materials whose capacities and performance are better than those available today. Carbon nanotubes（CNTs）, with their unique properties such as 1D tubular structure, high electrical and thermal conductivities, and extremely large surface area, have been used as materials to prepare cathodes for Li-ion batteries. The structure and morphology of CNTs were analyzed by X-ray diffraction（XRD）, scanning electron microscopy（SEM）, and transmission electron microscopy（TEM）. The functional groups on the purified CNT surface such as –COOH, –OH were characterized by Fourier Transform infrared spectroscopy. The electrode materials were fabricated from LiMn2O4（LMO）, doped spinel LiNi0.5Mn1.5O4, and purified CNTs via solid-state reaction. The structure and morphology of the electrode were characterized using XRD, SEM, and TEM. Finally, the efficiency of the electrode materials using CNTs was evaluated by cyclic voltammetry and electrochemical impedance spectroscopy.

关键词： Nanocomposites Carbon nanotubes(CNTs) Spinel materials Lithium-ion batteries(LIBs)

Development and bioequivalence study of potassium chloride extended release tablets

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Asian Journal of Pharmaceutical Sciences 2018年第4期13卷 353-359页

作者： Thu van le Thi Nghiem le Quan Hau le University of Medicine and Pharmacy at Ho Chi Minh city

The purposes of this study are to prepare the generic extended release tablet of potassiumchloride(PC) 600 mg and to compare the absorption of potassium ion from the experimen-tal tablets to that of Kaleorid? LP 600 mg(leo Pharmaceutical Products, Denmark). Car-nauba wax was used as retardant in the matrix core tablets. The core tablets were coatedwith blends of ethyl cellulose(EC) and hydroxypropyl methyl cellulose(HPMC) to modulatethe drug release. Results of a selective two-level, three-factor experiment design revealedthat a blend of 41.75% of EC and 58.25% of HPMC at 4.5% weight gained could produce thecoated tablets having dissolution profiles similar to those of Kaleorid?. A two-treatment,two-period, two-sequence crossover bioequivalence study was carried out on 24 healthyvolunteers to compare the absorption of potassium ion from experimental tablets to thatfrom Kaleorid?. The potassium ion in the urine was measured by a selective electrode of theADVIA 1650 system(Bayer) and used to calculate cumulative urinary excretion and urinaryexcretion rate. Results of 90 percent confidence interval analysis showed that the limits fornatural log-transformed cumulative urinary potassium excretion(Ln Ae 0-24) of test productwere in the range of 3.73–3.79 mEq, corresponding to 99.08%–100.92% of Kaleorid ?, respec-tively, and the limits for natural log-transformed maximal potassium excretion rate( R max) oftest product were in the range of 1.72–1.82 mEq/h, corresponding to 97.34%–102.66% of refer-ence product, respectively. Both of them fell within the bioequivalence interval(80%–125%)of reference product, proving that experimental product is bioequivalent to Kaleorid ?.

关键词： Potassium chloride Ethyl cellulose Hydroxypropyl methyl cellulose Extended release tablet Cumulative urinary excretion Urinary excretion rate

On Mixed Multiplicities of Good Filtrations

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Algebra Colloquium 2015年第3期22卷 421-436页

作者： Duong Quoc Viet le van Dinh Department of Mathematics Hanoi National University of Education 136 Xuan Thuy Street Hanoi Vietnam

This paper interprets mixed multiplicities of good filtrations as Hilbert-Samuel multiplicities, and shows that （ε1,..., εm）-superficial sequences in [16] （2007） and superficial sequences in [15] （1973） are weak-（FC）-sequences in [19] （2000）. As consequences, we not only obtain generalized results for mixed multiplicities of ideals in [15, 16, 19] but also get an improvement of [19, Theorem 3.4] that seems to account well for the essence of [16, Theorem 1.4].

关键词： mixed multiplicity filtration (FC)-sequence superficial sequence

Detecting Lumbar Implant and Diagnosing Scoliosis from Vietnamese X-Ray Imaging Using the Pre-Trained API Models and Transfer learning

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Computers, Materials & Continua 2021年第1期66卷 17-33页

作者： Chung le van Vikram Puri Nguyen Thanh Thao Dac-Nhuong le Duy Tan University Da Nang550000Vietnam Department of Radiology Hue University of Medicine and PharmacyHue UniversityHue530000Vietnam Institute of Research and Development Duy Tan UniversityDanang550000Vietnam Faculty of Information Technology Duy Tan UniversityDanang550000Vietnam

With the rapid growth of the autonomous system,deep learning has become integral parts to enumerate applications especially in the case of healthcare *** body vertebrae are the longest and complex parts of the human *** are numerous kinds of conditions such as scoliosis,vertebra degeneration,and vertebrate disc spacing that are related to the human body vertebrae or spine or *** detection of these problems is very important otherwise patients will suffer from a disease for a *** this proposed system,we developed an autonomous system that detects lumbar implants and diagnoses scoliosis from the modified Vietnamese x-ray *** applied two different approaches including pre-trained APIs and transfer learning with their pre-trained models due to the unavailability of sufficient x-ray medical *** results show that transfer learning is suitable for the modified Vietnamese x-ray imaging data as compared to the pre-trained API ***,we also explored and analyzed four transfer learning models and two pre-trained API models with our datasets in terms of accuracy,sensitivity,and specificity.

关键词： Lumbar implant diagnosing scoliosis X-Ray imaging transfer