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Nonlinear vibration analysis of fractional viscoelastic Euler–Bernoulli nanobeams based on the surface stress theory

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Acta mechanica Solida Sinica 2017年第4期30卷 416-424页

作者： m.Faraji Oskouie R.Ansari F.Sadeghi Department of mechanical Engineering University of Guilan

The nonlinear vibrations of viscoelastic Euler-Bernoulli nanobeams are studied using the fractional calculus and the Gurtin-murdoch theory. Employing Hamilton＇s principle, the governing equation considering surface effects is derived. The fractional integro-partial differential governing equation is first converted into a fractional-ordinary differential equation in the time domain using the Galerkin scheme. Thereafter, the set of nonlinear fractional time-dependent equations expressed in a state-space form is solved using the predictorcorrector method. Finally, the effects of initial displacement, fractional derivative order, viscoelasticity coefficient, surface parameters and thickness-to-length ratio on the nonlinear time response of simply-supported and clamped-free silicon viscoelastic nanobeams are investigated.

关键词： Fractional calculus Viscoelastic nanobeam Nonlinear vibrations

Chromatic framework for quantum movies and applications in creating montages

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Frontiers of Computer Science 2018年第4期12卷 736-748页

作者： Fei YAN Sihao JIAO Abdullah m. ILIYASU Zhengang JIANG School of Computer Science and Technology Changchun University of Science and Technology Changchun 130022 China Electrical Engineering Department College of Engineering Prince Sattam Bin Abdulaziz University Al-Kharj 11942 Saudi Arabia

A framework that introduces chromatic considerations to earlier descriptions of movies on quantum computers is proposed. This chromatic framework for quantum movies （CFQm） integrates chromatic components of individual frames （each a multi-channel quantum image - mCQI state） that make up the movie, while each frame is tagged to a time component of a quantum register （i.e., a movie strip）. The formulation of the CFQm framework and properties inherent to the mCQI images facilitate the execution of a cortege of carefully formulated transformations including the frame-to-frame （FTF）, color of interest （COI）, and subblock swapping （SBS） operations that are not realizable on other quantum movie formats. These innovative transformations are deployed in the creation of digital movie-like montages on the CFQm framework. Future studies could explore additional mCQI-related operations and their use to execute more advanced montage applications.

关键词： quantum information quantum computation quantum image processing quantum movie montage

Spherical Parameterization of marching Cubes IsoSurfaces Based upon Nearest Neighbor Coordinates

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Journal of Computer Science & Technology 2009年第1期24卷 30-38页

作者： Gregory m.Nielson 张丽艳李建黄辉扬 Arizona State University TempeAZU.S.A. Nanjing University of Aeronautics and Astronautics Handong Global University National Central University

We present some new methods for parameterizing the triangle mesh surface （TmS） which result from the marching Cubes （mC） algorithm. The methods apply to surfaces of genus zero and the parameter domain is a unit sphere. We take advantage of some special properties of the TmS resulting from the mC algorithm to obtain simple, computational efficient representations of the nearest neighbor coordinates and utilize these coordinates in the characterization of the parameterization by means of systems of equations which are solved iteratively. Examples and comparisons are presented.

关键词： isosurface marching cubes mapping parameterization spherical triangle mesh surface

Lower extremity injuries in vehicle-pedestrian collisions using a legform impactor model

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第2期11卷 97-105页

作者： A.ABVABI A.NASR A.NOORPOOR m.S.KIASAT Department of Automotive Engineering Iran University of Science and TechnologyTehranIran School of Railway Engineering Iran University of Science and TechnologyTehranIran Faculty of marine Technology Amirkabir University of TechnologyTehranIran

Though the bumper of a vehicle plays a major role in protecting the vehicle body against damage in low speed impacts, many bumpers, particularly in large vehicles, are too stiff for pedestrian protection. In designing a bumper for an automobile, pedestrian protection is as important as bumper energy absorption in low speed collisions. To prevent lower extremity injuries in car-pedestrian collisions, it is important to determine the loadings that car front structures impart on the lower extremities and the mechanisms by which injury is caused by these loadings. The present work was focused on gaining more insight into the injury mechanisms leading to both ligament damage and bone fracture during bumper-pedestrian collisions. The European Enhanced Vehicle-safety Committee （EEVC） legform impactor model was introduced and validated against EEVCAVG17 criteria. The collision mechanism between a bumper and this legform impactor was investigated numerically using LS-DYNA software. To identify the effect of the bumper beam material on leg injuries, four analyses were performed on bumpers that had the same assembly but were made from different materials.

关键词： Finite element model (FEm) Legform impactor Pedestrian safety Lower extremity injury Composite bumper

microstructure and mechanical properties of friction-stir welded St52 steel joints

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International Journal of minerals,metallurgy and materials 2018年第12期25卷 1457-1464页

作者： Tevfik kucukomeroglu Semih m.Aktarer Guven Ipekoglu Gurel Cam Department of mechanical Engineering Karadeniz Technical UniversityTrabzon 61080Turkey Department of Automotive Technology Recep Tayyip Erdogan UniversityRize 53100Turkey Department of mechanical Engineering Iskenderun Technical UniversityHatay 31200Turkey

The aim of this work is to investigate the mechanical properties and microstructures of friction-stir welded(FSWed) St52 structural steel joints. In this study, St52 steel plates with a thickness of 4 mm were butt-welded by friction-stir welding(FSW) using a tungsten carbide tool having a conical pin. The microstructure of the welded zone consists of equiaxed fine ferrite, grain boundary ferrite, Widmanstatten ferrite, and aggregates of ferrite + cementite. The microhardness measurements showed that the hardness of the welded zone was significantly higher than that of the base metal. The FSWed St52 joint exhibited a significant strength overmatching in the weld region and a strength performance similar to or slightly higher than that of the base plate.

关键词： friction-stir welding St52 steel microstructure mechanical properties

Pivotal role of long non-coding ribonucleic acid-X-inactive specific transcript in regulating immune checkpoint programmed death ligand 1 through a shared pathway between miR-194-5p and miR-155-5p in hepatocellular carcinoma

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World Journal of Hepatology 2020年第12期12卷 1211-1227页

作者： Sara m Atwa Heba Handoussa Karim m Hosny margarete Odenthal Hend m El Tayebi Pharmaceutical Biology Department German University in CairoCairo 11865Egypt Department of General Surgery Faculty of MedicineCairo UniversityCairo 11562Egypt Institute for Pathology University Hospital CologneCologne 50924Germany molecular Pharmacology Research Group Department of Pharmacology and ToxicologyFaculty of Pharmacy and BiotechnologyGerman University in CairoCairo 11835Egypt

BACKGROUND Anti-programmed death therapy has thrust immunotherapy into the ***,such therapy has a modest response in hepatocellular carcinoma(HCC).Epigenetic immunomodulation is a suggestive combinatorial therapy with immune checkpoint ***-coding ribonucleic acid(ncRNA)driven regulation is a major mechanism of epigenetic *** the wide range of ncRNAs that co-opt in programmed cell-death protein 1(PD-1)/programmed death ligand 1(PD-L1)regulation,and based on the literature,we hypothesized that miR-155-5p,miR-194-5p and long non-coding RNAs(lncRNAs)X-inactive specific transcript(XIST)and mALAT-1 are involved in a regulatory upstream pathway for PD-1/***,nutraceutical therapeutics in cancers have received increasing ***,it is interesting to study the impact of oleuropein on the respective study key *** To explore potential upstream regulatory ncRNAs for the immune checkpoint PD-1/*** Bioinformatics tools including *** and lnCeDB software were adopted to detect targeting of miR-155-5p,miR-194-5p and lncRNAs XIST and mALAT-1 to PD-L1 mRNA,*** addition,Diana tool was used to predict targeting of both aforementioned miRNAs to lncRNAs XIST and *** and normal tissue samples were collected for scanning of PD-L1,XIST and mALAT-1 *** study the interaction among miR-155-5p,miR-194-5p,lncRNAs XIST and mALAT-1,as well as PD-L1 mRNA,a series of transfections of the Huh-7 cell line was carried *** Bioinformatics software predicted that miR-155-5p and miR-194-5p can target PDL1,mALAT-1 and ***-1 and XIST were predicted to target PD-L1 ***-L1 and XIST were significantly upregulated in 23 HCC biopsies compared to healthy controls;however,mALAT-1 was barely ***-194 induced expression elevated the expression of PD-L1,XIST and ***,overexpression of miR-155-5p induced the upregulation of PD-L1 and XIST,while it had a negative impact on mA

关键词： Hepatocellular carcinoma X-inactive specific transcript miR-155-5p miR-194-5p Programmed cell-death protein 1/Programmed death ligand 1 Immune checkpoint

Development of a drill energy utilization index for aiding selection of drill machines in surface mines

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International Journal of mining Science and Technology 2017年第3期27卷 393-399页

作者： Kumar Suraj Rahul Talreja murthy V.m.S.R. Department of mining Engineering Indian School of Mines Dhanbad India

Drill machines used in surface mines, particularly in coal, is characterized by a very poor utilization （around 40%） and low availability （around 60%）. The main purpose of this study is to develop a drill selec- tion methodology and simultaneously a performance evaluation technique based on drill cuttings produced and drilling rate achieved. In all 28 blast drilled through were investigated. The drilling was accomplished by 5 different drill machines of Ingersoll-Rand and Revathi working in coal mines of Sonepur Bazari （SECL） and Block-II （BCCL）. The drills are Rotary and Rotary Percussive type using tri- cone rock roller bits. Drill cuttings were collected and sieve analysis was done in the laboratory. Using Rosin Ramler Diagram, coarseness index （CI）, mean chip size （d）, specific-st trace area （SSA） and charac- teristic particle size distribution curves for all the holes drilled were plotted. The predictor equation for drill penetration rate established through multiple regressions was found to have a very good correlation with an index of determination of 0.85. A comparative analysis of particle size distribution curves was used to evaluate the drill efficiency. The suggested approach utilises the area under the curve, after the point of trend reversal and brittleness ratio of the respective bench to arrive at drill energy utilization index （DEUI）, for mapping of drill machine to bench, The developed DEU1 can aid in selecting or mapping a right machine to right bench for achieving higher penetration rate and utilizations.

关键词： Drill cutting parameter Coarseness index mean chip size Specific surface area Particle size distribution curves Drill energy ptilization index

Bending of Euler-Bernoulli nanobeams based on the strain-driven and stress-driven nonlocal integral models: a numerical approach

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Acta mechanica Sinica 2018年第5期34卷 871-882页

作者： m.Faraji Oskouie R.Ansari H.Rouhi Department of mechanical Engineering University of GuilanP.O.Box 3756RashtIran Department of Engineering Science Faculty of Technology and EngineeringEast of GuilanUniversity of GuilanRudsar-Vajargah 44891-63157Iran

Eringen's nonlocal elasticity theory is extensively employed for the analysis of nanostructures because it is able to capture nanoscale *** studies have revealed that using the differential form of the strain-driven version of this theory leads to paradoxical results in some cases,such as bending analysis of cantilevers,and recourse must be made to the integral *** this article,a novel numerical approach is developed for the bending analysis of Euler-Bernoulli nanobeams in the context of strain-and stress-driven integral nonlocal *** numerical approach is proposed for the direct solution to bypass the difficulties related to converting the integral governing equation into a differential ***,the governing equation is derived based on both strain-driven and stress-driven nonlocal models by means of the minimum total potential ***,in each case,the governing equation is obtained in both strong and weak *** solve numerically the derived equations,matrix differential and integral operators are constructed based upon the finite difference technique and trapezoidal integration *** is shown that the proposed numerical approach can be efficiently applied to the strain-driven nonlocal model with the aim of resolving the mentioned ***,it is able to solve the problem based on the strain-driven model without inconsistencies of the application of this model that are reported in the literature.

关键词： Eringen's nonlocal theory Stress-driven model Strain-driven model Euler-Bernoulli beam Numerical approach Paradox

Interactive Effects of Potassium and Phosphorus on Phenology and Grain Yield of Sunflower in Northwest Pakistan

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Pedosphere 2010年第5期20卷 674-680页

作者： AmANULLAH m.W.KHAN Department of Agronomy Faculty of Crop Production SciencesKPK Agricultural University

Potassium(K) and phosphorus(P) applications improve growth,increase yield and yield components of sunflower(Helianthus annuus L.) on K and P deficient soils in Northwest Pakistan.A field experiment was conducted using sunflower ***-33 at the New Developmental Research Farm of KPK Agricultural University,Peshawar,Pakistan,during summer *** experimental design was a randomized complete block in split plot arrangements,with six levels of K(0,25,50,75,100,and 125 kg K ha-1) as main plots and four levels of P(0,45,90,and 135 kg P ha-1) as sub-plots with three *** yield and yield components responded positively to K and P fertilization but the magnitude of response varied with the levels of K and *** to flowering and maturity,grains per head,1000-grain weight,shelling percentage,and grain yield increased tremendously in the K and P-fertilized plots as compared to the control with no K and P *** combined application of 100 kg K and 45 kg P ha-1 significantly increased yield components,grain yield,harvest index,and shelling percentage of sunflower,suggesting that 100 kg K ha-1 in combination with 45 kg P ha-1 could maximize productivity of sunflower planted after wheat on the K and P deficient soils in the study area.

关键词： days to flowering days to maturity harvest index soil yield components