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Visualizing traumatic brain injury:ocular clues for diagnosis and assessment

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Neural Regeneration Research 2025年第5期20卷 1399-1400页

作者： Morteza Abyadeh Vivek Gupta Yuyi You Joao A.Paulo mehdi Mirzaei ProGene Technologies Pty Ltd SydneyNSWAustralia Department of Clinical Medicine Faculty of MedicineHealth and Human SciencesMacquarie Medical SchoolMacquarie UniversityMacquarie ParkNorth RydeSydneyNSWAustralia Department of Cell Biology Harvard Medical SchoolBostonMAUSA

Traumatic brain injury (TBI) is defined as damage to the brain resulting from an external sudden physical force or shock to the *** is considered a silent public health epidemic causing significant death and disability *** were 64,000 TBI related deaths reported in the USA in 2020,with about US$76 billion in direct and indirect medical costs annually.

关键词： diagnosis ocular injury

Microstructural characteristics and second-phase particles in yttrium-bearing Fe-10Ni-7Mn martensitic steels

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Journal of Rare Earths 2014年第4期32卷 326-333页

作者： F.Forghani M.nili-ahmadabadi School of Metallurgy and Materials Engineering College of EngineeringUniversity of Tehran Center of Excellence for High Performance Materials University of Tehran

In this study, the microstructure and second-phase particles in yttrium （0.05 wt.%and 0.8 wt.%） bearing Fe-10Ni-7Mn steels were characterized. The results of X-ray analysis as well as scanning electron microscopy coupled with energy dispersive X-ray spectroscopy indicated the formation of （Fe, Ni, Mn）17Y2 precipitates with hexagonal structure in a Fe-10Ni-7Mn-0.8Y （wt.%） alloy. Lattice parameters of these precipitates were calculated as follows：a=0.8485 nm and c=0.8274 nm. Formation of Y2O3 sub-micron particles was also confirmed in both yttrium bearing steels via electrolytic phase extraction method. The effect of these precipitates on the prior austenite grain size was investigated. The results revealed that these precipitates had an effective role in controlling the prior austenite grain size.

关键词： Fe-10Ni-7Mn (wt.%) steel yttrium addition microstructure characterization second-phase particles grain growth rare earths

Surface second-harmonic generation based on periodically poled LiNbO_3 nonlinear optical crystal

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Chinese Physics B 2011年第5期20卷 266-271页

作者： H.nili-ahmadabadi A.R.Khorsandi Department of Physics Esfahan UniversityHezar Jarib Street81746-73441 EsfahanI.R.Iran

We have generated a second-harmonic generation （SHG） of a Q-switched microchip Nd：YAG laser on the surface of a periodically poled LiNbO3 （PPLN） nonlinear crystal near the grazing incidence angle. Three individual SHC waves as transmitted homogeneous, kthomogeneous and reflected radiations have been generated and their intensities are measured and characterized within a desirable range of about 10 different incidence angles of the Nd：YAG laser as pump source on the PPLN surface. The basic of surface nonlinear radiation is also investigated and similar results are calculated and extracted from the theory. Comparison between calculated and measured data shows that they are in good agreement with each other.

关键词： surface SIqG Nd:YAG laser PPLN nonlinear crystal

Effects of coarse riblets on air flow structures over a slender delta wing using particle image velocimetry

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Chinese Journal of Aeronautics 2019年第6期32卷 1367-1379页

作者： Mahdi nili-ahmadabadi Omid NEMATOLLAHI Kyung Chun KIM Department of Mechanical Engineering Isfahan University of TechnologyIsfahan 84156-83111Iran School of Mechanical Engineering Pusan National UniversityBusan 609-735Republic of Korea

This research investigates the aerodynamic performance and flow characteristics of a delta wing with 65° sweep angle and with coarse axial riblets,and then compares with that of a smooth-surface delta *** Image Velocimetry(PIV)were utilized to visualize the flow over the wing at 6 cross-sections upright to the wing surface and parallel to the wing span,as well as 3 longitudinal sections on the leading edge,symmetry plane,and a plane between them at Angles of Attack(AOA)=20°and 30°and Re=1.2×10~5,2.4×10~5,and 3.6×10~*** effects of the riblets were studied on the vortices diameter,vortex breakdown location,vortices distance from the wing surface,flow lines pattern nearby the wing,circulation distribution,and *** results show that the textured model has a positive effect on some of the parameters related to drag reduction and lift *** riblets increase the flow momentum near the wing’s upper surface except near the *** also increase the flow momentum behind the wing.

关键词： Aerodynamic performance Coarse riblet Delta wing Flow structures Particle image velocimetry Vortex

A novel approach for the design of axial flow fan by increasing by-pass ratio in a constantdiameter turbofan

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Propulsion and Power Research 2020年第2期9卷 142-158页

作者： Ali Shahsavari Mahdi nili-ahmadabadi Department of Mechanical Engineering.Isfahan University of Technology Isfahan***Iran

The present study introduces an innovative aerodynamic redesign of an axial flow fan based on constant diffusion factor and radial *** input design parameters such as mass flow rate,hub to tip ratio,aspect ratio,tip diameter and angular velocity are taken from NASA Rotor 67 as a conventional axial flow fan.A computer program is developed to extract the three-dimensional geometry of a fan and to estimate the span-wise distribution of *** new designed fan flow field is investigated in detail by CFD tool at both design and off design ***,a turbofan cycle analysis is conducted based on thermodynamic and gas dynamic principles to evaluate the fan performance in a turbofan engine in comparison to NASA Rotor *** a higher total pressure ratio,meeting the target pressure ratio in lower rotational speed with higher efficiency,delivering more bypass air in a constant diameter and less fuel consumption for the same specific thrust force are the main advantages for the new design strategy in comparison to the conventional designed fans such as Rotor ***,efficiency reduction in fan over speed is the main disadvantage.

关键词： Axial flow fan Bypass ratio Computer simulation Design methodology Thermodynamic turbofan cycle analysis

IMPLICITY LINEAR COLLOCATION METHOD AND ITERATED IMPLICITY LINEAR COLLOCATION METHOD FOR THE NUMERICAL SOLUTION OF HAMMERSTEIN FREDHOLM INTEGRAL EQUATIONS ON 2D IRREGULAR DOMAINS

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Journal of Computational Mathematics 2020年第4期38卷 624-637页

作者： H.Laeli Dastjerdi M.nili ahmadabadi Department of Mathematics Farhangian UniversityTehranIran Department of Mathematics Najafabad BranchIslamic Azad UniversityNajafabadIran

In this work,we adapt and compare implicity linear collocation method and iterated implicity linear collocation method for solving nonlinear two dimensional Fredholm integral equations of Hammerstein type using IMQ-RBFs on a non-rectangular *** show to be the most promising RBFs for this kind of *** proposed methods are mesh-free and they are independent of the geometry of *** analysis of the proposed methods together with some benchmark examples are provided which support their reliability and numerical stability.

关键词： Two dimensional equations Irregular domain Fredholm integral equations Mesh-less method Numerical treatment

Investigation of a Centrifugal Compressor and Study of the Area Ratio and TIP Clearance Effects on Performance

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Journal of Thermal Science 2008年第4期17卷 314-323页

作者： Mahdi nili-ahmadabadi Ali Hajilouy-Benisi Mohammad Durali Farhad Ghadak School of Mechanical Engineering Center of Excellence in Energy ConversionSharif University of Technology Aerospace Engineering Department Emam Hossein University

In this research, the centrifugal compressor of a turbocharger is investigated experimentally and numerically. Performance characteristics of the compressor were obtained experimentally by measurements of rotor speed and flow parameters at the inlet and outlet of the compressor. Three dimensional flow field in the impeller and dif- fuser was analyzed numerically using a full Navier-Stokes program with SST turbulence model. The performance characteristics of the compressor were obtained numerically, which were then compared with the experimental results. The comparison shows good agreement. Furthermore, the effect of area ratio and tip clearance on the performance parameters and flow field was stud- ied numerically. The impeller area ratio was changed by cutting the impeller exit axial width from an initial value of 4.1 mm to a final value of 5.1 mm, resulting in an area ratio from 0.792 to 0.965. For the rotor with exit axial width of 4.6 mm, performance was investigated for tip clearance of 0.0, 0.5 and 1.0 mm. Results of this simula- tion at design point showed that the compressor pressure ratio peaked at an area ratio of 0.792 while the effi- ciency peaked at a higher value of area ratio of 0.878. Also the increment of the tip clearance from 0 to 1 mm resulted in 20 percent efficiency decrease.

关键词： centrifugal compressor area ratio tip clearance effect

Numerical study of camber and stagger angle effects on the aerodynamic performance of tandem-blade cascades

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Propulsion and Power Research 2018年第1期7卷 30-42页

作者： Behshad Ghazanfari Mahdi nili-ahmadabadi Ashkan Torabi-Farsani Mohammad Hossein Noorsalehi Department of Mechanical Engineering Isfahan University of TechnologyIsfahan ***Iran

Jet engine manufacturers and designers are seeking for lighter and smaller type of axial *** the aerodynamic characteristics of blades is carried out by controlling the boundary *** way to control the boundary layer is using tandem ***-blade cascades are capable of using highly loaded stages for axial compressors because they provide more works than single-blade *** other words,tandem blades help to achieve a specified total pressure ratio with less number of ***,one of the most important problems for researchers is to optimize the aerodynamic parameters of tandem *** the geometrical parameters of blades is a method to achieve this *** this work,the stagger and camber angle of each blade are first changed while the other geometrical parameters such as overall camber,total stagger angle,the axial overlap,percent pitch and chord ratio are ***,the overall camber angle of tandem blade is changed by increasing the difference between the stagger angle of the first and second blade while the type of two airfoils,axial overlap and percent pitch,overall chord length and overall stagger angle are *** aerodynamic performances of the generated tandem-blade cascades are obtained using two-dimensional numerical solution of *** this,a viscous turbulent flow solver is used for solving the Navier-Stokes *** these simulations,inlet Mach number is fixed to 0.6.

关键词： Tandem blade Axial compressors Cascade Camber angle Stagger angle Flow deflection Loss coefficient

Effects of slope plate variable and reheating on semi-solid structure of ductile cast iron

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China Foundry 2008年第1期5卷 36-38页

作者： M. nili-ahmadabadi F. Pahlevani P. Babaghorbani School of Metallurgy and Materials Engineering University of Tehran Tehran Iran

Semi-solid metal casting and forming are known as a promising process for a wide range of metalalloys production. In spite of growing application of semi-solid processed light alloys, a few works have been reportedabout semi-solid processing of iron and steel. In this research inclined plate was used to change dendritic structureof iron to globular one. The effects of length and slope of plate on the casting structure were examined. The resultsshow that the process can effectively change the dendritic structure to globular. In the slope plate angle of 7.5? andlength of 560 mm with cooling rate of 67K·s-1 the optimum nodular graphite and solid globular particle were *** results also show that by using slope plate inoculant fading can be prevented more easily since the total time ofprocess is rather short. In addition, the semi-solid ductile cast iron prepared by inclined plate method, was reheated to examine the effectof reheating conditions on the microstructure and coarsening kinetics of the alloy. Solid fraction at different reheatingtemperatures and holding time was obtained and based on these results the optimum reheating temperature rangewas determined.

关键词： ductile cast iron semi-solid reheating thixoforming