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A Hybrid Optimization Approach of Single point Incremental Sheet Forming of AISI 316L Stainless Steel Using Grey Relation Analysis Coupled with principal Component Analysiss

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 160-166页

作者： A Visagan p Ganesh Department of production Technology Madras Institute of TechnologyChennai-600044India

We investigated the parametric optimization on incremental sheet forming of stainless steel using Grey Relational Analysis(GRA) coupled with principal Component Analysis(pCA). AISI 316L stainless steel sheets were used to develop double wall angle pyramid with aid of tungsten carbide tool. GRA coupled with pCA was used to plan the experiment conditions. Control factors such as Tool Diameter(TD), Step Depth(SD), Bottom Wall Angle(BWA), Feed Rate(FR) and Spindle Speed(SS) on Top Wall Angle(TWA) and Top Wall Angle Surface Roughness(TWASR) have been studied. Wall angle increases with increasing tool diameter due to large contact area between tool and workpiece. As the step depth, feed rate and spindle speed increase,TWASR decreases with increasing tool diameter. As the step depth increasing, the hydrostatic stress is raised causing severe cracks in the deformed surface. Hence it was concluded that the proposed hybrid method was suitable for optimizing the factors and response.

关键词： single point incremental forming AISI 316L taguchi grey relation analysis principal component analysis surface roughness scanning electron microscopy

potential physiological and pathological roles for axonal ryanodine receptors

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Neural Regeneration Research 2023年第4期18卷 756-759页

作者： David p.Stirling Kentucky Spinal Cord Injury Research Center and Departments of Neurological Surgery Anatomical Sciences and NeurobiologyMicrobiology and ImmunologyUniversity of LouisvilleSchool of MedicineLouisvilleKYUSA

Clinical disability following trauma or disease to the spinal cord often involves the loss of vital white matter elements including axons and glia.Although excessive Cais an established driver of axonal degeneration,therapeutically targeting externally sourced Cato date has had limited success in both basic and clinical studies.Contributing factors that may underlie this limited success include the complexity of the many potential sources of Caentry and the discovery that axons also contain substantial amounts of stored Cathat if inappropriately released could contribute to axonal demise.Axonal Castorage is largely accomplished by the axoplasmic reticulum that is part of a continuous network of the endoplasmic reticulum that provides a major sink and source of intracellular Cafrom the tips of dendrites to axonal terminals.This“neuron-within-a-neuron”is positioned to rapidly respond to diverse external and internal stimuli by amplifying cytosolic Calevels and generating short and long distance regenerative Cawaves through Cainduced Carelease.This review provides a glimpse into the molecular machinery that has been implicated in regulating ryanodine receptor mediated Carelease in axons and how dysregulation and/or overstimulation of these internodal axonal signaling nanocomplexes may directly contribute to Ca-dependent axonal demise.Neuronal ryanodine receptors expressed in dendrites,soma,and axonal terminals have been implicated in synaptic transmission and synaptic plasticity,but a physiological role for internodal localized ryanodine receptors remains largely obscure.plausible physiological roles for internodal ryanodine receptors and such an elaborate internodal binary membrane signaling network in axons will also be discussed.

关键词： axomyelinic synapse axon axoplasmic reticulum calcium ryanodine receptor secondary axonal degeneration spinal cord injury voltage-gated calcium channel white matter injury

Effects of site productivity on individual tree maximum basal area growth rates of Eucalyptus pilularis in subtropical Australia

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林业研究:英文版 2023年第6期34卷 1659-1668页

作者： p.W.West Forest Research Centre Southern Cross UniversityLismoreNSW 2480Australia

Inventory data were available from 96 plots of even-aged,monoculture,tall-open forests of Eucalyptus pilularis Smith,aged 2-63 years,growing in sub-tropical regions along the east coast of Australia.A model was developed relating the maximum possible stem basal area growth rate of individual trees to their stem basal area.For any tree size,this maximum increased as site productivity increased.However,the size at which this maximum occurred decreased as productivity increased.Much research has shown that,at any stand age,trees of a particular stem basal area are taller on more productive sites than on less productive ones.Taller trees incur greater respiratory costs to ensure maintenance of the photo synthetic capacity of their canopies;this reduces their growth rates.It was concluded that trees with larger basal areas will have the maximum possible growth rate on a less productive site,whilst trees with smaller basal areas will have the maximum possible on a more productive site.The model developed may constitute the first stage of a complete individual tree growth model system to predict wood yields from these forests.

关键词： Growth model Individual tree Maximum growth rate Eucalyptus pilularis physiological eff ects

Can lithium enhance the extent of axon regeneration and neurological recovery following peripheral nerve trauma?

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Neural Regeneration Research 2022年第5期17卷 948-952页

作者： Damien p.Kuffler Institute of Neurobiology Medical Sciences CampusUniversity of Puerto RicoSan JuanPRUSA

The clinical"gold standard"technique for attempting to restore function to nerves with a gap is to bridge the gap with sensory autografts.However,autografts induce good to excellent recovery only across short nerve gaps,in young patients,and when repairs are performed a short time post nerve trauma.Even under the best of conditions,patients recover good recovery.Although many alternative techniques have been tested,none is as effective as autografts.Therefore,alternative techniques are required that increase the percentage of patients who recover function and the extent of their recovery.This paper examines the actions of lithium,and how it appears to trigger all the cellular and molecular events required to promote axon regeneration,and how both in animal models and clinically,lithium administration enhances both the extent of axon regeneration and neurological recovery.The paper proposes more extensive clinical testing of lithium for its ability and reliability to increase the extent of axon regeneration and functional recovery.

关键词： anastomosis axon regeneration lithium nerve crush nerve gaps nerve repair nerve trauma neurological recovery Schwann cells

Windows of opportunity:a new tree-shrub dynamic at alpine treeline?

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National Science Review 2023年第10期10卷 13-14页

作者： Grant p.Elliott Department of Geography University of Missouri

Of increasing importance while the climate is under the influence of chronic environmental change driven by rising levels of CO2,temperature and vapor pressure deficit(VpD),is understanding how vegetation will respond over space and time as we cross critical thresholds [1].This is especially true in mountain regions where amplified rates of warming are expected to affect the elevational zonation of plant communities [2].

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Adhesion at friction and wear

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Friction 2022年第11期10卷 1859-1878页

作者： Dmitry p.MARKOV Research Institute of Railway Transport Moscow 129851Russia

Our understanding of the surrounding world,from friction to the origin of life,depends on how we imagine the contact interaction of condensed bodies.What are the forces acting in contact with solids?Do they attract(adhesive)or repel(dehesive)?Theory and research at the atomic–molecular level have shown that the force are adhesive,but everyday experiences cast doubt on this conclusion.This article addresses this issue by considering the mistakes made in experimental and theoretical tribology and surface physics.Taking into account the theories of hybridization and dehybridization of electron orbitals and valence bonds,the views on the structure of the surfaces of condensed bodies and the force arising during contact interaction are revised.The influence of van der Waals,hydrogen,covalent,metallic,and ionic bonds on the properties of lubricants is evaluated.The contours of the dehesive–deformation theory of friction and wear are also outlined.

关键词： atomic and molecular interactions adhesion cohesion dehesion friction wear

Assessment of risks, implications, and opportunities of waterborne neurotoxic pesticides

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Journal of Environmental Sciences 2023年第3期125卷 735-741页

作者： Delaram Dara Andrei p.Drabovich Division of Analytical and Environmental Toxicology Department of Laboratory Medicine and PathologyFaculty of Medicine and DentistryUniversity of AlbertaAlberta T6G 2G3Canada

pesticides are a well-known family of chemicals that have contaminated water systems globally. Four common subfamilies of pesticides include organochlorines, organophosphates, pyrethroids, and carbamate insecticides which have been shown to adversely affect the human nervous system. Studies have shown a link between pesticide exposure and decreased viability, proliferation, migration, and differentiation of murine neural stem cells. Besides human exposure directly through water systems, additional factors such as pesticide bioaccumulation, biomagnification and potential synergism due to co-exposure to other environmental contaminants must be considered. A possible avenue to investigate the molecular mechanisms and biomolecules impacted by the various classes of pesticides includes the field of-omics. Discovery of the precise molecular mechanisms behind pesticidemediated neurodegenerative disorders may facilitate development of targeted therapeutics.Likewise, discovery of pesticide biodegradation pathways may enable novel approaches for water system bioremediation using genetically engineered microorganisms. In this minireview, we discuss recently established harmful impacts of various categories of pesticides on the nervous system and the application of-omics field for discovery, validation, and mitigation of pesticide neurotoxicity.

关键词： Neurotoxic pesticides Water pollution Neural stem cells Omics approaches Drug discovery

Design of Hierarchical Classifier to Improve Speech Emotion Recognition

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Computer Systems Science & Engineering 2023年第1期44卷 19-33页

作者： p.Vasuki Department of IT Sri Sivasubramaniya Nadar College of EngineeringChennai603110India

Automatic Speech Emotion Recognition(SER)is used to recognize emotion from speech automatically.Speech Emotion recognition is working well in a laboratory environment but real-time emotion recognition has been influenced by the variations in gender,age,the cultural and acoustical background of the speaker.The acoustical resemblance between emotional expressions further increases the complexity of recognition.Many recent research works are concentrated to address these effects individually.Instead of addressing every influencing attribute individually,we would like to design a system,which reduces the effect that arises on any factor.We propose a two-level Hierarchical classifier named Interpreter of responses(IR).Thefirst level of IR has been realized using Support Vector Machine(SVM)and Gaussian Mixer Model(GMM)classifiers.In the second level of IR,a discriminative SVM classifier has been trained and tested with meta information offirst-level classifiers along with the input acoustical feature vector which is used in primary classifiers.To train the system with a corpus of versatile nature,an integrated emotion corpus has been composed using emotion samples of 5 speech corpora,namely;EMO-DB,IITKGp-SESC,SAVEE Corpus,Spanish emotion corpus,CMU's Woogle corpus.The hierarchical classifier has been trained and tested using MFCC and Low-Level Descriptors(LLD).The empirical analysis shows that the proposed classifier outperforms the traditional classifiers.The proposed ensemble design is very generic and can be adapted even when the number and nature of features change.Thefirst-level classifiers GMM or SVM may be replaced with any other learning algorithm.

关键词： Speech emotion recognition hierarchical classifier design ensemble emotion speech corpora

Carbon capture for decarbonisation of energy-intensive industries:a comparative review of techno-economic feasibility of solid looping cycles

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Frontiers of Chemical Science and Engineering 2022年第9期16卷 1291-1317页

作者： Mónica p.S.Santos Dawid p.Hanak Energy and power School of WaterEnergy and EnvironmentCranfield UniversityBedfordshire MK430ALUK

Carbon capture and storage will play a crucial role in industrial decarbonisation.However,the current literature presents a large variability in the techno-economic feasibility of CO_(2)capture technologies.Consequently,reliable pathways for carbon capture deployment in energyintensive industries are still missing.This work provides a comprehensive review of the state-of-the-art CO_(2)capture technologies for decarbonisation of the iron and steel,cement,petroleum refining,and pulp and paper industries.Amine scrubbing was shown to be the least feasible option,resulting in the average avoided CO_(2)cost of between 62.7∈t_(CO_(2))^(-1)for the pulp and paper and 104.6∈t_(CO_(2))^(-1)for the iron and steel industry.Its average equivalent energy requirement varied between 2.7(iron and steel)and 5.1MJ_(th)·kg_(CO_(2))^(-1)(cement).Retrofits of emerging calcium looping were shown to improve the overall viability of CO_(2)capture for industrial decarbonisation.Calcium looping was shown to result in the average avoided CO_(2)cost of between 32.7(iron and steel)and 42.9(cement).Its average equivalent energy requirement varied between 2.0(iron and steel)and 3.7(pulp and paper).Such performance demonstrated the superiority of calcium looping for industrial decarbonisation.Further work should focus on standardising the techno-economic assessment of technologies for industrial decarbonisation.

关键词： industrial CO_(2)emissions CCS deployment carbonate looping net-zero industry carbon capture benchmarks