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Dietary soluble non-starch polysaccharide level and xylanase supplementation influence performance,egg quality and nutrient utilization in laying hens fed wheat-based diets

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Animal Nutrition 2021年第2期7卷 512-520页

作者： Xa h.nguyen h.ng t.nguyen Natalie K.Morgan University of New England School of Environmental and Rural ScienceArmidaleNew South Wales2351Australia

the aim of this study was to evaluate the effects of dietary soluble non-starch polysaccharide(sNSP)content and xylanase supplementation on production performance,egg quality parameters,and nutrient di-gestibility in hy-line Brown layers from 25 to 32 wk of age.A total of 144 hy-line Brown laying hens(25 wk of age)were randomly allocated to 1 of 4 wheat-based dietary treatments in a 2×2 factorial experimental design,with 36 replicates of individual hens per *** diets were formulated to contain either a high or low sNSP level(at 13.3 or 10.8 g/kg)and were supplemented with either 0 or 12,000 BXU/kg exogenous *** were fed these treatment diets for an 8-wk period,and hen production perfor-mance,including daily egg production,average egg weight,daily egg mass,feed conversion ratio and pro-portion of dirty and abnormal eggs were measured at bird age 25 to 28 wk and 29 to 32 *** interaction between sNSP content of the diet and xylanase supplementation was observed on daily egg production from 25 to 28 wk of age(P-0.018);birds fed the high sNSP diet without xylanase had lower egg production than those fed any other *** interaction between the 2 dietary factors was also observed on hen weight gain at 29 to 32 wk of age(P=0.014),with birds fed the low sNSP diet with 12,000 BXU/kg xylanase presenting greater weight gain compared to those fed the high sNSP diet with 12,000 BXU/kg *** intake at 29 to 32 wk of age was reduced by xylanase supplementation(P=0.047).Xylanase supplemen-tation also increased yolk colour score at both 28 and 32 wk of age,and decreased yolk weight at 32 wk of age(P-0.014,0.037 and 0.013,respectively).Birds fed the low sNSP diet presented lower protein digestibility(P-0.024)than those fed the high sNSP ***,birds fed high sNSP presented higher shell reflectivity at both 28 and 32 wk of age(P-0.05 and 0.036,respectively).the influence of duration of feeding the treatment diets on egg quality was also

关键词： Soluble NSP Xylanase Laying hen Production performance Egg quality

A higher order coupled frequency characteristics study of smart magneto-electro-elastic composite plates with cut-outs using finite element methods

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Defence technology（防务技术） 2021年第1期17卷 100-118页

作者： M.Vinyas D.harursampath t.nguyen thoi Nonlinear Multifunctional Composites Analysis and Design(NMCAD)Laboratory Department of Aerospace EngineeringIndian Institute of ScienceBangalore560012India Division of Computational Mathematics and Engineering Institute for Computational ScienceTon Duc Thang UniversityHo Chi Minh CityViet Nam Faculty of Civil Engineering Ton Duc Thang UniversityHo Chi Minh CityViet Nam

this article deals with investigating the effect of cut-outs on the natural frequencies of magneto-electroelastic(MEE)plates incorporating finite element methods based on higher order shear deformation theory(hSDt).In order to consider the influence of cut-out,the energy of the cut-out domain is subtracted from the total energy of the entire *** governing equations of motions are derived through incorporating hamilton’s principle and the solution is obtained using condensation *** proposed numerical formulation is verified with the results of previously published literature as well as the numerical *** addition,this research focuses on evaluating the effect of geometrical skewness and boundary conditions on the frequency *** influence of cut-outs on the degree of coupling between magnetic,electric and elastic fields is also investigated.

关键词： Cut-out Magneto-electro-elastic Natural frequency higher order shear deformation Coupling

Assessing impacts of energy storage on resilience of distribution systems against hurricanes

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Journal of Modern Power Systems and Clean Energy 2019年第4期7卷 731-740页

作者： hieu t.nguyen John W.MUhS Masood PARVANIA Department of Electrical and Computer Engineering University of UtahSalt Lake CityUT 84112USA

this paper develops a comprehensive framework to analyze the impact of energy storage on improving the resilience of distribution systems against *** paper first develops a spatio-temporal model of progressing hurricane when making landfall that can be used to anticipate outage scenarios caused by the gust-wind *** optimization model is then developed for optimizing the operation of distribution systems during hurricane that captures both pre-outage and post-outage network operation *** simulations are performed on the modified IEEE 33-bus distribution system with real hurricane data in houston to demonstrate the effectiveness of the proposed model.

关键词： Resilience hurricane Energy storage Distribution system

Free vibration analysis of laminated FG-CNt reinforced composite beams using finite element method

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Frontiers of Structural and Civil Engineering 2019年第2期13卷 324-336页

作者： t.VO-DUY V.hO-hUU t.nguyen-thOI Division of Computational Mathematics and Engineering Institute for Computational ScienceTon Due Thang UniversityHo Chi Minh CityVietnam Faculty of Civil Engineering Ton Due Thang UniversityHo Chi Minh CityVietnam

In the present study, the free vibration of laminated functionally graded carbon nanotube reinforced composite beams is analyzed. the laminated beam is made of perfectly bonded carbon nanotubes reinforced composite (CNtRC) layers. In each layer, single-walled carbon nanotubes are assumed to be unifonnly distributed (UD) or functionally graded (FG) distributed along the thickness direction. Effective material properties of the two-phase composites, a mixture of carbon nanotubes (CNts) and an isotropic polymer, are calculated using the extended nile of mixture. the first-order shear deformation theory is used to formulate a governing equation for predicting free vibration of laminated functionally graded carbon nanotubes reinforced composite (FG?CNtRC) beams. the governing equation is solved by the finite element method with various boundary conditions. Several numerical tests are perfbnned to investigate the influence of the CNts volume fractions, CNts distributions, CNts orientation angles, boundary conditions, length-to-thickness ratios and the numbers of layers on the frequencies of the laminated FG-CNtRC beams. Moreover, a laminated composite beam combined by various distribution types of CNts is also studied.

关键词： free vibration analysis laminated FG-CNtRC beam finite element method first-order shear deformation theory composite material

A Note on Skew Cyclic Codes over a Class of Rings

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Algebra Colloquium 2020年第4期27卷 703-712页

作者： hai Q.Dinh Bac t.nguyen Songsak Sriboonchitta Division of Computational Mathematics and Engineering Institute for Computational Science Ton Due Thang University Ho Chi Minh CityVietnam Faculty of Mathematics and Statistics Ton Due Thang University Ho Chi Minh CityVietnam Department of Basic Sciences University of Economics and Business Administration Thai Nguyen UniversityThai Nguyen ProvinceVietnam Centre of Excellence in Econometrics Faculty of Economics Chiang Mai UniversityChiang Mai 52000Thailand

We study skew cyclic codes over a class of rings R=F0■F1■⋯■Ft−1,where each Fi(i=0,…,t−1)is a finite *** prove that a skew cyclic code of arbitrary length over R is equivalent to either a usual cyclic code or a quasi-cyclic code over ***,we discuss possible extension of our results in the more general setting ofδR-dual skew constacyclic codes over R,whereδR is an automorphism of R.

关键词： skew constacyclic codes dual codes repeated-root codes quasi-cyclic codes local rings

Bi-Objective Optimal Control Modification Adaptive Control for Systems with Input Uncertainty

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IEEE/CAA Journal of Automatica Sinica 2014年第4期1卷 423-434页

作者： Nhan t.nguyen Sivasubramanya N.Balakrishnan the NASA Ames Research Center Moffett Field the Missouri University of Science and technology

this paper presents a new model-reference adaptive control method based on a bi-objective optimal control formulation for systems with input uncertainty. A parallel predictor model is constructed to relate the predictor error to the estimation error of the control effectiveness matrix. In this work, we develop an optimal control modification adaptive control approach that seeks to minimize a bi-objective linear quadratic cost function of both the tracking error norm and the predictor error norm simultaneously. the resulting adaptive laws for the parametric uncertainty and control effectiveness uncertainty are dependent on both the tracking error and the predictor error, while the adaptive laws for the feedback gain and command feedforward gain are only dependent on the tracking error. the optimal control modification term provides robustness to the adaptive laws naturally from the optimal control framework. Simulations demonstrate the effectiveness of the proposed adaptive control approach.

关键词： Optimal control Adaptive control Uncertainty Adaptation models Robustness Cost function NASA Learning (artificial intelligence)

Imaging disturbance zones ahead of a tunnel by elastic full-waveform inversion:Adjoint gradient based inversion *** space reduction using a level-set method

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Underground Space 2018年第1期3卷 21-33页

作者： Andre Lamert Luan t.nguyen Wolfgang Friederich tamara Nestorovic Seismology Institute of GeologyMineralogy and GeophysicsRuhr-Uniersity BochumGermany Reservoir Engineering and Rock Physics International Geothermal CenterBochuon University of Applied SciencesGermany Mechanics of Adaptive Systems Institute of Computational EngineeringRudhr-Umiversity BochumGermany

We present and compare twoﬂexible and effective methodologies to predict disturbance zones ahead of underground tunnels by using elastic full-waveform *** methodology uses a linearized,iterative approach based on misﬁt gradients computed with the adjoint method while the other uses iterative,gradient-free unscented Kalmanﬁltering in conjunction with a level-set *** the former does not involve a priori assumptions on the distribution of elastic properties ahead of the tunnel,the latter intro-duces a massive reduction in the number of explicit model parameters to be inverted for by focusing on the geometric form of potential disturbances and their average elastic *** imaging methodologies are validated through successful reconstructions of simple *** an application,we consider an elastic multiple disturbance *** using identical synthetic time-domain seismo-grams as test data,we obtain satisfactory,albeit different,reconstruction results from the two inversion *** computa-tional costs of both approaches are of the same order of magnitude,with the gradient-based approach showing a slight *** model parameter space reduction approach compensates for this by additionally providing a posteriori estimates of model parameter uncertainty.

关键词： tunnel seismics Full waveform inversion Seismic waves Level-set method Adjoint method Kalman filter

Influence of active constrained layer damping on the coupled vibration response of functionally graded magneto-electro-elastic plates with skewed edges

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Defence technology（防务技术） 2020年第5期16卷 1019-1038页

作者： M.Vinyas D.harursampath t.nguyen-thoi Nonlinear Multifunctional Composites Analysis and Design(NMCAD)Laboratory Department of Aerospace EngineeringIndian Institute of ScienceBangalore560012India Division of Computational Mathematics and Engineering Institute for Computational ScienceTon Duc Thang UniversityHo Chi Minh CityViet Nam Faculty of Civil Engineering Ton Duc Thang UniversityHo Chi Minh CityViet Nam

this article makes the first attempt in assessing the influence of active constrained layer damping(ACLD)treatment towards precise control of frequency responses of functionally graded skew-magneto-electroelastic(FGSMEE)plates by employing finite element *** materials are functionally graded across the thickness of the plate in terms of modest power-law *** principal equations of motion of FGSMEE are derived via hamilton’s principle and solved using condensation *** effect of ACLD patches are modelled by following the complex modulus approach(CMA).Additionally,distinctive emphasis is laid to evaluate the influence of geometrical skewness on the attenuation capabilities of the *** accuracy of the current analysis is corroborated with comparison of previous researches of similar ***,a complete parametric study is directed to understand the combined impacts of various factors like coupling fields,patch location,fiber orientation of piezoelectric patch in association with skew angle and power-law index.

关键词： Vibration control Functionally graded MEE plates Skew angle Active constrained layer damping(ACLD) patches

A deep neural network based surrogate model for damage identification in full-scale structures with incomplete noisy measurements

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 393-410页

作者： tram BUI-ngOC Duy-Khuong LY tam t tRUOng Chanachai th.ngChOM t.nguyen-thOI Laboratory for Computational Mechanics Institute for Computational Science and Artificial IntelligenceVan Lang UniversityHo Chi Minh City 70000Vietnam Faculty of Mechanical-Electrical and Computer Engineering School of TechnologyVan Lang UniversityHo Chi Minh City 70000Vietnam Faculty of Civil Engineering School of TechnologyVan Lang UniversityHo Chi Minh City 70000Vietnam Department of Computer Science Aarhus UniversityAarhus 8000Denmark thammasat University research unit in structural and foundation engineering Department of Civil EngineeringThammasat UniversityPathumthani 12120Thailand Laboratory for Applied and Industrial Mathematics Institute for Computational Science and Artificial IntelligenceVan Lang UniversityHo Chi Minh City 70000Vietnam thammasat School of Engineering Thammasat UniversityPathumthani 12120Thailand

the paper introduces a novel approach for detecting structural damage in full-scale structures using surrogate models generated from incomplete modal data and deep neural networks(DNNs).A significant challenge in this field is the limited availability of measurement data for full-scale structures,which is addressed in this paper by generating data sets using a reduced finite element(FE)model constructed by SAP2000 software and the MAtLAB programming *** surrogate models are trained using response data obtained from the monitored structure through a limited number of measurement *** proposed approach involves training a single surrogate model that can quickly predict the location and severity of damage for all potential *** achieve the most generalized surrogate model,the study explores different types of layers and hyperparameters of the training algorithm and employs state-of-the-art techniques to avoid overfitting and to accelerate the training *** approach’s effectiveness,efficiency,and applicability are demonstrated by two numerical *** study also verifies the robustness of the proposed approach on data sets with sparse and noisy measured ***,the proposed approach is a promising alternative to traditional approaches that rely on FE model updating and optimization algorithms,which can be computationally *** approach also shows potential for broader applications in structural damage detection.

关键词： vibration-based damage detection deep neural network full-scale structures finite element model updating noisy incomplete modal data