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Frontiers of Structural and Civil Engineering 2024年第9期18卷 1401-1423页

作者： Thu Huong NGUYEN THI Van Ke TRAN Quoc Hoa PHAM School of Mechanical and Automotive Engineering Hanoi University of IndustryHanoi 100000Vietnam faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoi 100000Vietnam faculty of Engineering and Technology Nguyen Tat Thanh UniversityHo Chi Minh City 700000Vietnam

This work uses isogeometric analysis(IGA),which is based on nonlocal hypothesis and higher-order shear beam hypothesis,to investigate the static bending and free oscillation of a magneto-electro-elastic functionally graded(MEE-FG)nanobeam subject to elastic boundary constraints(BCs).The magneto-electric boundary condition and the Maxwell equation are used to calculate the variation of electric and magnetic potentials along the thickness direction of the *** study is innovative since it does not use the conventional boundary ***,an elastic system of straight and torsion springs with controllable stiffness is used to support nanobeams’beginning and end positions,creating customizable *** governing equations of motion of nanobeams are established by applying Hamilton’s principle and IGA is used to determine deflections and natural frequency *** studies were performed to evaluate the convergence and accuracy of the proposed *** from this,the impact of the input parameters on the static bending and free oscillation of the MEE-FG nanobeam is examined in *** findings could be valuable for analyzing and designing innovative structures constructed of functionally graded MEE materials.

关键词： elastic boundary conditions isogeometric analysis nanobeam via nonlocal theory grading of magneto-electro-elastic functions

Exploring impacts of COVID-19 on spatial and temporal patterns of visitors to Canadian Rocky Mountain National Parks from social media big data

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Journal of forestry Research 2024年第4期35卷 13-33页

作者： Dehui Christina Geng Amy Li Jieyu Zhang Howie W.Harshaw Christopher Gaston Wanli Wu Guangyu Wang National Park Research Centre Faculty of ForestryUniversity of British ColumbiaVancouver V6T 1Z4Canada faculty of Applied Science University of British ColumbiaVancouver V6T 1Z3Canada Paul G.Allen School of Computer Science&Engineering University of WashingtonSeattleWA 98195USA faculty of Kinesiology Sportand RecreationUniversity of AlbertaEdmonton T6G 2J9Canada Department of Wood Science Faculty of ForestryUniversity of British ColumbiaVancouver V6T 1Z4Canada

COVID-19 posed challenges for global tourism *** in visitor temporal and spatial patterns and their associated determinants pre-and peri-pandemic in Canadian Rocky Mountain National Parks are *** was collected through social media programming and analyzed using spatiotemporal analysis and a geographically weighted regression(GWR)*** highlight that COVID-19 significantly changed park visitation *** tended to explore more remote areas *** GWR model also indicated distance to nearby trails was a significant influence on visitor *** results indicate that the pandemic influenced tourism temporal and spatial *** research presents a novel approach using combined social media big data which can be extended to the field of tourism management,and has important implications to manage visitor patterns and to allocate resources efficiently to satisfy multiple objectives of park management.

关键词： Tourism management Social media big data National parks COVID-19 Geographical weighted regression

Cooperative THz communication for UAVs in 6G and beyond

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Green Energy and Intelligent Transportation 2024年第1期3卷 25-31页

作者： Nazifa Mustari Muhammet Ali Karabulut A.F.M.Shahen Shah Ufuk Tureli Department of Electronics and Communication Engineering Yildiz Technical UniversityTurkey Department of Electrical Electronics Engineering Faculty of Engineering and ArchitectureKafkas UniversityKarsTurkey

One of the key components of any smart city is considered to be its intelligent transportation systems(ITSs).Unmanned aerial vehicles(UAVs)are envisioned in several ITS application fields because of their autonomous operation,mobility,communication/processing capabilities,and other *** this paper,cooperative terahertz(THz)communication is proposed for flying ad hoc networks(FANETs),which is a particular kind of network made up of a collection of small UAVs linked in an ad hoc fashion and working together to accomplish high-level *** frequency spectrum for wireless communication has been expanding continuously in order to meet the demand for *** the forthcoming 6G and beyond,communications in the THz range will be vital,similar to how mmWave-band communications are currently influencing the 5G of wireless mobile *** finite state machine(FSM)of the proposed cooperative communication system for THz band is presented.A Markov chain model-based analytical study is carried out,which derives relationships among ***,numerical results are provided to support the analytical study.

关键词： Cooperative MAC THz UAVs 6G

Characteristics of Biopellets Manufactured from Various Lignocellulosic Feedstocks as Alternative Renewable Energy Sources

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Journal of Renewable Materials 2024年第6期12卷 1103-1123页

作者： Anggara Ridho Putra Apri Heri Iswanto Arif Nuryawan Saptadi Darmawan ElvaraWindra Madyaratri Widya Fatriasari Lee Seng Hua Petar Antov Harisyah Manurung Ade Pera Amydha Sudrajat Herawati Pendi Department of Forest Products Faculty of ForestryUniversitas Sumatera Utara.Kampus USU Padang BulanMedan20155Indonesia Research Center for Biomass and Bioproducts National Research and Innovation Agency(BRIN)Jl Raya Bogor KM 46 CibinongBogor16911Indonesia Department of Wood Industry Faculty of Applied SciencesUniversiti Teknologi MARA(UiTM)Cawangan Pahang Kampus JengkaShah Alam26400Malaysia faculty of Forest Industry University of ForestrySofia1797Bulgaria

The increased valorization of renewable and cost-effective lignocellulosic feedstocks represents a viable,sustainable,and eco-friendly approach toward the production of biopellets as alternative energy *** aim of this research work was to investigate and evaluate the feasibility of using various lignocellulosic raw materials,i.e.,raru(Cotylelobium melanoxylon),mangrove(Rhizophora spp.),sengon(Paraserianthes falcataria),kemenyan toba(Styrax sumatrana),oil palm(Elaeis guineensis),manau rattan(Calamus manan),and belangke bamboo(Gigantochloa pruriens)for manufacturing biopellets with different particle *** raw materials used were tested for their moisture content,specific gravity,ash,cellulose,and lignin *** addition,thermal analyses,i.e.,calorific values,thermogravimetric analysis(TGA),and differential scanning calorimetry(DSC),were *** following properties of the biopellets produced were investigated:moisture content,volatile matter,ash content,fixed carbon,density,and thermal *** on an analysis of the raw materials,raru had the lowest moisture content(12%)and ash content(1.5%)and the highest specific gravity(1.2).Markedly,palm oil stem had the highestα-cellulose(55%)and lignin(37%)*** accordance with the SNI 8675:2018 standard requirements,biopellets with optimal properties(moisture content of 1.4%,ash content of 0.79%,density of 1.09 g/m^(3),calorific value of 4672 cal/g,and TGA residue of 13.9%),were manufactured from raru wood.

关键词： Biomass biopellet renewable energy particle size

Exact solution for thermal vibration of multi-directional functionally graded porous plates submerged in fluid medium

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Defence Technology（防务技术） 2024年第5期35卷 77-99页

作者： Quoc-Hoa Pham Van Ke Tran Phu-Cuong Nguyen faculty of Engineering and Technology Nguyen Tat Thanh UniversityHo Chi Minh CityViet Nam faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoiViet Nam Advanced Structural Engineering Laboratory Department of Structural EngineeringFaculty of Civil EngineeringHo Chi Minh City Open UniversityHo Chi Minh CityViet Nam

An analytical method for analyzing the thermal vibration of multi-directional functionally graded porous rectangular plates in fluid media with novel porosity patterns is developed in this *** properties of MFG porous plates change according to the length,width,and thickness directions for various materials and the porosity distribution which can be widely applied in many fields of engineering and defence ***,new porous rules that depend on spatial coordinates and grading indexes are proposed in the present *** Hamilton's principle and the refined higher-order shear deformation plate theory,the governing equation of motion of an MFG porous rectangular plate in a fluid medium(the fluid-plate system)is *** fluid velocity potential is derived from the boundary conditions of the fluid-plate system and is used to compute the extra *** GalerkinVlasov solution is used to solve and give natural frequencies of MFG porous plates with various boundary conditions in a fluid *** validity and reliability of the suggested method are confirmed by comparing numerical results of the present work with those from available works in the *** effects of different parameters on the thermal vibration response of MFG porous rectangular plates are studied in *** findings demonstrate that the behavior of the structure within a liquid medium differs significantly from that within a vacuum ***,they offer appropriate operational approaches for the structure when employed in various mediums.

关键词： Plate-fluid contact Galerkin Vlasov's method Multi-directional functionally graded plate Novel porosity Thermal vibration Refined higher-order shear deformation theory

Influences of the tank liquid lateral sloshing and mass time-varying on high clearance self-propelled sprayer ride comfort

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International Journal of Agricultural and Biological Engineering 2024年第1期17卷 12-22页

作者： Liquan Lu Junchang Zhang Cui Cui Jun Chen Yu Chen Hongling Jing Shuo Zhang Sugirbay Adilet Chenwei Hu Jiayu Cao College of Mechanical and Electronic Engineering Northwest A&F UniversityYangling 712100ShaanxiChina Weifang Engineering Vocational College Weifang 261000ShandongChina technical faculty S.Seifullin Kazakh Agro Technical UniversityAstana 101400Kazakhstan

To explore the influence of the lateral sloshing and the time-varying mass of the liquid in the tank on the ride comfort of the high-clearance sprayer,a spring-mass-damping equivalent mechanics that can describe the lateral sloshing of the liquid under different filling ratios was constructed based on the equivalent *** Fluent was used to simulate the moment acting on the wall of the tank by the lateral sloshing of the liquid,and then the parameters of the equivalent mechanical model are obtained by fitting and *** analysis of Fluent simulation and bench test on lateral sloshing of tank liquid under different filling *** results show that the lateral sloshing trend of the tank liquid level obtained from the Fluent simulation and the bench test was consistent,which proved the accuracy of the Fluent fluid simulation process and the correctness of the required equivalent mechanical model *** a liquid sloshing equivalent model,a four-degree-of-freedom vertical dynamic model of the sprayer half-car was ***,the performance of the sprayer was systematically analyzed and compared under the excitation of a bump road and a random E-level *** investigation took into account varying liquid filling ratios of 10%,50%,and 90%.The focus lay on evaluating the vertical acceleration of the sprayer body,dynamic deflection of the suspension,and dynamic load on the tires in response to these road *** analysis is conducted independently of the liquid sloshing *** results show that the lateral sloshing of the liquid medicine significantly reduces the ride smoothness of the machine,and makes the vibration response of the machine produce a certain hysteresis *** the reduction of the quality of the liquid medicine in the spray tank,the vibration amplitude of the sprayer body gradually decreases,the hysteresis effect is also gradually *** results presented in this study offer a

关键词： high clearance self-propelled sprayer liquid lateral sloshing ride comfort system dynamics simulation

An isogeometric approach to static and transient analysis of fluid-infiltrated porous metal foam piezoelectric nanoplates with flexoelectric effects and variable nonlocal parameters

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 461-489页

作者： Quoc-Hoa PHAM Van Ke Tran Phu-Cuong Nguyen faculty of Engineering and Technology Nguyen Tat Thanh UniversityHo Chi Minh City 700000Vietnam faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoi 100000Vietnam Advanced Structural Engineering Laboratory Department of Structural EngineeringFaculty of Civil EngineeringHo Chi Minh City Open UniversityHo Chi Minh City 700000Vietnam

In this work,a novel refined higher-order shear deformation plate theory is integrated with nonlocal elasticity theory for analyzing the free vibration,bending,and transient behaviors of fluid-infiltrated porous metal foam piezoelectric nanoplates resting on Pasternak elastic foundation with flexoelectric *** analysis(IGA)and the Navier solution are applied to the *** innovation in the present study is that the influence of the in-plane variation of the nonlocal parameter on the free and forced vibration of the piezoelectric nanoplates is investigated for the first *** nonlocal parameter and material characteristics are assumed to be material-dependent and vary gradually over the thickness of *** on Hamilton’s principle,equations of motion are built,then the IGA approach combined with the Navier solution is used to analyze the static and dynamic response of the ***,we investigate the effects of the porosity coefficients,flexoelectric parameters,elastic stiffness,thickness,and variation of the nonlocal parameters on the mechanical behaviors of the rectangular and elliptical piezoelectric nanoplates.

关键词： isogeometric analysis fluid-infiltrated porous piezoelectric nanoplates static and transient analysis flexoelectric effect variable nonlocal parameters

A New Framework for Software Vulnerability Detection Based on an Advanced Computing

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Computers, Materials & Continua 2024年第6期79卷 3699-3723页

作者： Bui Van Cong Cho Do Xuan Department of Information Technology University of Economics and Technical IndustriesHanoi100000Vietnam faculty of Information Security Posts and Telecommunications Institute of TechnologyHanoi100000Vietnam

The detection of software vulnerabilities written in C and C++languages takes a lot of attention and interest *** paper proposes a new framework called DrCSE to improve software vulnerability *** uses an intelligent computation technique based on the combination of two methods:Rebalancing data and representation learning to analyze and evaluate the code property graph(CPG)of the source code for detecting abnormal behavior of software *** do that,DrCSE performs a combination of 3 main processing techniques:(i)building the source code feature profiles,(ii)rebalancing data,and(iii)contrastive *** which,the method(i)extracts the source code’s features based on the vertices and edges of the *** method of rebalancing data has the function of supporting the training process by balancing the experimental ***,contrastive learning techniques learn the important features of the source code by finding and pulling similar ones together while pushing the outliers *** experiment part of this paper demonstrates the superiority of the DrCSE Framework for detecting source code security vulnerabilities using the Verum *** a result,the method proposed in the article has brought a pretty good performance in all metrics,especially the Precision and Recall scores of 39.35%and 69.07%,respectively,proving the efficiency of the DrCSE *** performs better than other approaches,with a 5%boost in Precision and a 5%boost in ***,this is considered the best research result for the software vulnerability detection problem using the Verum dataset according to our survey to date.

关键词： Source code vulnerability source code vulnerability detection code property graph feature profile contrastive learning data rebalancing

Research on the Implementation Path of Ideological and Political Education in the“Horticultural Plant Production Technology”Course under the Rural Revitalization Strategy

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Journal of Contemporary Educational Research 2024年第8期8卷 32-37页

作者： Yuhong Yuan Fujian forestry Vocational technical College Nanping 353000Fujian ProvinceChina

The horticultural industry plays an important role in the rural revitalization *** the core course of horticultural technology,“Horticultural Plant Production Technology”shoulders an important mission in serving the rural revitalization strategy and cultivating a group of rural revitalization talents who truly love agriculture,know agricultural techniques,and understand *** the dimension of ideological and political education in the curriculum,based on the strategy of rural revitalization,the implementation path of ideological and political education in the curriculum is expanded and improved from the construction of education models,curriculum team building,excavation of ideological and political elements,and construction of evaluation systems,in order to improve the level of ideological and political education in horticultural plant production technology courses and provide certain reference and guidance for the ideological and political construction of similar agricultural vocational education courses.

关键词： Rural revitalization Agricultural vocational education Ideological and political education Implementation path

Thermoelectric performance of BiSnTemonolayer with ultralow lattice thermal conductivity induced by hybrid bonding properties:A theoretical prediction

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Science China Technological Sciences 2024年

作者： TANG ShuWei WANG Hao WAN Da LI XiaoDong GUO WanRong ZHENG Tuo QI XiuLing BAI ShuLin College of Materials Science and Engineering Liaoning Technical University faculty of Chemistry Northeast Normal University

The crystal structure,mechanical stability,phonon dispersion,electronic transport properties and thermoelectric （TE） performance of the Bi2Sn2Te6monolayer are assessed with the first-principles calculations and the Boltzmann transport *** Bi2Sn2Te6monolayer is an indirect semiconductor with a band gap of 0.91 eV using the Heyd-Scuseria-Ernzerhof （HSE06）functional in consideration of the spin-orbit coupling （SOC） *** Bi2Sn2Te6monolayer is high thermodynamically and mechanically stable by the assessments of elastic modulus,phonon dispersion curves,and ab initio molecular dynamics （AIMD）*** hybrid bonding characteristics are discovered in Bi2Sn2Te6monolayer,which is advantageous for phonon *** antibonding interactions near the Fermi level weaken the chemical bonding and reduce the phonon vibrational *** to the short phonon relaxation time,strong anharmonic scattering,large Grüneisen parameter,and small phonon group velocity,an ultralow lattice thermal conductivity (0.27 W/（m·K）@300K) is achieved for the *** optimal dimensionless figure of merit （ZT） values for the n-type and p-type Bi2Sn2Te6monolayers are 2.68 and 1.63 at 700 K,respectively,associated with a high TE conversion efficiency of 20.01%at the same ***,the Bi2Sn2Te6monolayer emerges as a promising candidate for TE material with high conversion efficiency.

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