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Acta Metallurgica sinica(English Letters) 1996年第6期9卷 443-452页

作者： Z.Q. Hu W.r.sun and s.r. Guo(Institute of Metal research, Chinese Academy of sciences, shenyang 110015, China

The effects of the trace elements, P, s and si,on the solidification, segregation,microstructure and mechanical properties of GH761 and In718 alloys were *** was found that the segregation of the P,s and si can be greatly aggravated or relieved by the precipitation taking place during the solidification. In the heat treated state,P enhances the intergranular precipitation in the GH761 *** refinement of P in In718 alloy causes the appearance of a film-like δ*** increases the intergranular precipitation of the M_6C and the Laves Phase in the In718 alloy.P, s and si play diverse roles in the tensile and the stress rupture properties of the GH761 and In718 alloys. The most striking effect is that P significantly prolongs the stress rupture lives of the GH761 and In718 alloys in a wide range of 0.00050.015 wt% .The mechanisms by which P,s and si influence the superalloys are discussed in the text.

关键词： superalloy,segregation microstructure mechanical property

An Intelligent sDN-IoT Enabled Intrusion Detection system for Healthcare systems Using a Hybrid Deep Learning and Machine Learning Approach

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China Communications 2024年第10期21卷 267-287页

作者： r Arthi s Krishnaveni sherali Zeadally Computational Intelligence School of ComputingSRMISTKattankulathurChennaiIndia College of Communication and Information University of KentuckyUSA

The advent of pandemics such as COVID-19 significantly impacts human behaviour and lives every ***,it is essential to make medical services connected to internet,available in every remote location during these ***,the security issues in the Internet of Medical Things(IoMT)used in these service,make the situation even more critical because cyberattacks on the medical devices might cause treatment delays or clinical ***,services in the healthcare ecosystem need rapid,uninterrupted,and secure *** solution provided in this research addresses security concerns and services availability for patients with critical health in remote *** research aims to develop an intelligent software Defined Networks(sDNs)enabled secure framework for IoT healthcare *** propose a hybrid of machine learning and deep learning techniques(DNN+sVM)to identify network intrusions in the sensor-based healthcare *** addition,this system can efficiently monitor connected devices and suspicious ***,we evaluate the performance of our proposed framework using various performance metrics based on the healthcare application *** experimental results show that the proposed approach effectively detects and mitigates attacks in the sDN-enabled IoT networks and performs better that other state-of-art-approaches.

关键词： deep neural network healthcare intrusion detection system IoT machine learning software-defined networks

Enhanced microstructural stability and mechanical properties of the Ag-containing Mg-Gd-Y alloys

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Journal of Magnesium and Alloys 2020年第4期8卷 1109-1119页

作者： s.Najafi r.Mahmudi school of Metallurgical and Materials Engineering College of EngineeringUniversity of TehranTehranIran

The effect of 0.5,1 and 1.5 wt%Ag addition on the microstructural evolution,thermal stability and mechanical properties of an Mg-5 wt%Gd-1 wt%Y(GW51)alloy was *** as-cast microstructure of the base alloy consisted of the Mg5(Gd,Y)phase in the a-Mg *** obtained results revealed that Ag addition refines the dendritic microstructure of the base alloy,promotes the formation of the new Mgi6Gd2YAg phase,and increases the volume fraction of the Mg5(Gd,Y)*** events resulted in improved hardness,strength,and microstructural stability of the Ag-containing alloys in the as-cast condition and after prolonged exposure to high *** superior mechanical properties of the quaternary alloys over those of the tertiary alloy at low and high temperatures stems from the solid solution hardening effect of Ag,presence of the thermally stable Mgi6Gd2YAg particles,and higher volume fraction of the Mg5(Gd,Y)*** particles can slow down the grain growth during exposure to high temperature,enhancing the stability and strength of the alloys at both room and high temperatures.

关键词： Mg-Gd-Y alloy Ag addition Thermal stability Mechanical properties.

Olfactory receptors in neural regeneration in the central nervous system

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Neural regeneration research 2025年第9期20卷 2480-2494页

作者： rafael Franco Claudia Garrigós Toni Capó Joan serrano-Marín rafael rivas-santisteban Jaume Lillo Molecular Neurobiology Laboratory Department of Biochemistry and Molecular BiomedicineFacultat de BiologiaUniversitat de BarcelonaBarcelonaSpain CiberNed Network Center for Biomedical research in Neurodegenerative Diseases Spanish National Health Institute Carlos ⅢMadridSpain school of Chemistry Universitat de BarcelonaBarcelonaSpain Department of Biochemistry and Physiology School of Pharmacy and Food SciencesUniversitat de BarcelonaBarcelonaSpain Laboratory of Computational Medicine Biostatistics UnitFaculty of MedicineAutonomous University of BarcelonaCampus BellaterraBarcelonaSpain

Olfactory receptors are crucial for detecting odors and play a vital role in our sense of smell,influencing behaviors from food choices to emotional *** receptors also contribute to our perception of flavor and have potential applications in medical diagnostics and environmental *** ability of the olfactory system to regenerate its sensory neurons provides a unique model to study neural regeneration,a phenomenon largely absent in the central nervous *** gained from how olfactory neurons continuously replace themselves and reestablish functional connections can provide strategies to promote similar regenerative processes in the central nervous system,where damage often results in permanent *** the molecular and cellular mechanisms underpinning olfactory neuron regeneration could pave the way for developing therapeutic approaches to treat spinal co rd injuries and neurodegenerative diseases like Alzheimer's *** ctory receptors are found in almost any cell of eve ry orga n/tissue of the mammalian *** ectopic expression provides insights into the chemical structures that can activate olfactory *** addition to odors,olfactory receptors in ectopic expression may respond to endogenous compounds and molecules produced by mucosal colonizing *** analysis of the function of olfactory receptors in ectopic expression provides valuable information on the signaling pathway engaged upon receptor activation and the receptor's role in proliferation and cell differentiation *** review explo res the ectopic expression of olfa ctory receptors and the role they may play in neural regeneration within the central nervous system,with particular attention to compounds that can activate these receptors to initiate regenerative *** suggests that olfactory receptors could serve as potential therapeutic targets for enhancing neural repair and recovery following central nervous syste

关键词： adenosine receptors adrenergic receptors ectopic expression G proteincoupled receptors glia neurons

High-Velocity Projectile Impact Behaviour of Friction stir Welded AA7075 Thick Plates

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Defence Technology（防务技术） 2023年第11期29卷 153-163页

作者： r.Praveen s.r.Koteswara rao G.selvakumar r.Damodaram Department of robotics and Automation Karpaga Vinayaga College of Engineering and TechnologyChengalpattu603308TamilNaduIndia Department of Mechanical Engineering Sri Sivasubramaniya Nadar College of EngineeringChennai603110TamilNaduIndia

In this study, high velocity impact behaviour of friction stir welded AA7075-T651 25 mm thick plates were investigated using a 7.62 mm × 51 mm lead core and 7.62 mm × 39 mm steel core projectiles. Prior to ballistic trails, mechanical and metallurgical properties of friction stir welded AA 7075-T651 25 mm thick plates were studied. Microstructural and hardness studies revealed that friction stir welds constituted three distinct regions namely Weld Nugget(WN), Thermo-Mechanically Affected Zone(TMAZ) and Heat Affected Zone(HAZ). Base Material(BM) and all three weld regions were ballistically tested as per military standard NIJ.0108.01 using lead and steel core bullets at maximum permissible velocities of 830 ± 20 and 700 ± 30 m/s, respectively. It has been found that base material(AA7075-T651)and all three weld regions of 25 mm thick plates were able to resist perforation by both types of projectiles used. However depth of penetration has been found to increase from BM to WN, HAZ and TMAZ for both types of projectiles. In all cases steel core projectiles caused higher depth of penetration compared to those caused by lead core projectiles. TMAZs of the friction stir welds were found to be the weakest zone. The fracture that occurred in the base material was spall fragmentation indicating brittle failure, whereas all zones of friction stir welded AA7075-T651 targets with a front petalling, indicating ductile failure. The post-ballistic tested samples showed no significant change in the microstructure of the BM and WN. On the other hand, TMAZ and HAZ showed severe grain deformation in the direction of projectile penetration, and the formation of adiabatic shear bands(AsB). This work showed that 25 mm thick friction stir welded AA7075-T651 joints responded well to ballistic impact loads, making them a good choice for light combat vehicles.

关键词： Aluminum alloy Thick plate Friction stir welding Ballistic performance Depth of penetration

Microstructures and mechanical properties of dissimilar Nd:YAG laser weldments of AIsI4340 and AIsI316L steels

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International Journal of Minerals,Metallurgy and Materials 2017年第5期24卷 538-549页

作者： A.r.sufizadeh s.A.A.Akbari Mousavi school of Metallurgy and Materials Engineering College of EngineeringUniversity of TehranTehran 11155-4563Iran

This paper presents studies on the microstructure and mechanical properties of AIsI 316L stainless steel and AIsI 4340 low-alloy steel joints formed by the Nd:YAG laser welding process. The weld microstructures and heat affected zones (HAZs) were investigated. Austenitic microstructures were observed in all of the samples. The sizes of the HAZs changed when the heat input was varied, and the 316L sides exhibited a larger HAZ. The cooling rates were calculated by measuring the solidification dendrite arm spacing. It is shown that high cooling rates lead to an austenitic microstructure. Tensile tests were carried out, and the results revealed the tensile properties of both the base metals and the weldments. The hardness test results agreed well with the tensile test results.

关键词： stainless steel laser welding welded joints microstructure mechanical properties cooling rate

ENTrOPY TOLErANT FUZZY C-MEANs IN MEDICAL IMAGEs

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Journal of Innovative Optical Health sciences 2011年第4期4卷 447-462页

作者： s.r.KANNAN s.rAMATHILAGAM r.DEVI YUEH-MIN HUANG Department of Mathematics ramanujan school of Mathematical sciences Pondicherry University India Department of Mathematics Periyar Government College CuddaloreIndia Department of Engineering science National Cheng Kung University TainanTaiwan

segmenting the Dynamic Contrast-Enhanced Breast Magnetic resonance Images(DCE-BMrI)is an extremely important task to diagnose the disease because it has the highest specificity when acquired with high temporal and spatial resolution and is also corrupted by heavy noise,outliers,and other imaging *** this paper,we intend to develop efficient robust segmentation algorithms based on fuzzy clustering approach for segmenting the *** proposed segmentation algorithms have been amalgamated with effective kernel-induced distance measure on standard fuzzy c-means algorithm along with the spatial neighborhood information,entropy term,and tolerance vector into a fuzzy clustering structure for segmenting the *** significant feature of our proposed algorithms is its capability tofind the optimal membership grades and obtain effective cluster centers automatically by minimizing the proposed robust objective ***,this article demonstrates the superiority of the proposed algorithms for segmenting DCE-BMrI in comparison with other recent kernel-based fuzzy c-means *** the clustering accuracies of the proposed algorithms are validated by using silhouette method in comparison with existed fuzzy clustering algorithms.

关键词： Fuzzy clustering algorithms entropy method segmentation medical images

APPrOXIMATE EsTIMATION OF HArDENING-sOFTENING BEHAVIOUr OF CIrCULAr PIPEs sUBJECTED TO PUrE BENDING

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Acta Mechanica sinica 1997年第3期13卷 227-240页

作者：杨嘉陵 s.r.reid The solid Mechanics research Centre Beijing University of Aeronautics and AstronauticsBeijing 100083China Department of Mechanical Engineering UMISTP.O.Box 88Manchester M60 1QDUK

An approximate method for describing the plastic hardening-softening behaviour of circular pipes subjected to pure bending is presented. Theoretical estimation based on the uniform ovalization model and local collapse model proposed in the paper is incorporated to give several simple formulations with reasonable accuracy for determining the relationship between bending moment (M) and curvature (kappa) in the purely bended pipes. Attention is focused on the critical curvature associated with maximum resistant moment and the maximum change in the original diameter before the end of uniform ovalization stage as well as the local collapse behaviour. some comparisons between analytical results and experimental results are made in order to examine the theory.

关键词： hardening-softening behaviour pure bended pipes circular pipes deformation characteristics of pipes

Two-Layer Non-Hydrostatic Model for Generation and Propagation of Interfacial Waves

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China Ocean Engineering 2019年第1期33卷 65-72页

作者： s.r.Pudjaprasetya I.Magdalena Industrial and Financial Mathematics research Group Faculty of Mathematics and Natural SciencesInstitut Teknologi Bandung

When pycnocline thickness of ocean density is relatively small, density stratification can be well represented as a two-layer system. In this article, a depth integrated model of the two-layer fluid with constant density is considered,and a variant of the edge-based non-hydrostatic numerical scheme is formulated. The resulting scheme is very efficient since it resolves the vertical fluid depth only in two layers. Despite using just two layers, the numerical dispersion is shown to agree with the analytical dispersion curves over a wide range of kd, where k is the wave number and d the water depth. The scheme was tested by simulating an interfacial solitary wave propagating over a flat bottom, as well as over a bottom step. On a laboratory scale, the formation of an interfacial wave is simulated,which also shows the interaction of wave with a triangular bathymetry. Then, a case study using the Lombok strait topography is discussed, and the results show the development of an interfacial wave due to a strong current passing through a sill.

关键词： interfacial waves two-layer non-hydrostatic model dispersion relation

si_3N_4/Ni nanocomposite formed by electroplating: Effect of average size of nanoparticulates

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Transactions of Nonferrous Metals society of China 2010年第6期20卷 1017-1023页

作者： M.A.KHAZrAYIE A.r.s.AGHDAM Department of Materials Engineering Faculty of Engineering Tarbiat Modares University

Properties of si3N4/Ni electroplated nanocomposite such as corrosion current density after long time immersion,roughness of obtained layer and distribution of nanometric particulates were *** effective factors for fabrication of nanocomposite coatings were fixed for better studying the effect of the average size of *** effects of the different average size of nanometric particulates(AsNP)from submicron scale(less than 1μm)to nanometric scale(less than 10 nm)were *** nanostructures of surfaces were examined by scanning electron microscopy(sEM),transmission electron microscopy(TEM)and atomic force microscopy(AFM).Corrosion rates of the coatings were determined using the Tafel polarization *** is seen that decreasing the AsNP will lead to lower corrosion current densities;however,in some cases,pitting phenomena are *** roughness illustrates a minimum level while the distribution of nanometric particulates is more uniform by decreasing the *** effects of pulsed current on electrodeposition(frequency,duty cycle)and concentration of nanoparticulates in electrodeposition bath on trend of obtained curves have been *** surface methodology was applied for optimizing the effective operating conditions of *** levels studied were frequency range between 1 000 and 9 000 Hz,duty cycle between 10%and 90%and concentration of nanoparticulates of 10-90 g/L.

关键词： corrosion electrodeposition nanocomposite nanostructure nano diamond