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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

Discharging granular material from a rotary kiln in a slumping regime： Theoretical and experimental studies

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particuology 2015年第6期13卷 56-61页

作者： A, Donatelli p. Garzone p. Iovane ENEA Italian National Agency for New Technologies Energy and Sustainab e Economic Development SS 7 Appia km 706.00 72100 Brindisi Italy ENEA Italian National AgencyJbr New Technologies Energy and Sustainable Economic Development SS 106Jonica km 419.50075026 Rotondella (MT) Italy

This study developed a theoretical approach to understanding how a set amount of a granular bed is discharged from a tilted rotary kiln （an empty cylinder） once its particle size distribution （pSD） is known and slumping motion occurs. The basis of the study is that the preparation of material for thermal treat- ment inside a rotary kiln （pyrolysis, gasification, and]or combustion） involves shredding to a desired particle size. Further mechanical stress results from the feeder screws moving material from storage toward the reactor. The most common pSDs found in uniform size reduction processes and mechanical stresses are Gaussian, log-normal, and Rosin-Rammler, of which the latter best fits the pSD in our study. Different particle diameters in the distribution result in an axial segregation when a slumping motion occurs, resulting in particles of different diameters leaving the kiln at different instants. After develop- ing the model, the theoretical data showed good agreement when compared with experimental results obtained from downloading previously shredded carbonaceous material from a rotary kiln at 2 and 4 rpm rotational speeds. The mean residence times at steady state were determined for both rotational speeds and showed good agreement with data provided in the literature.

关键词： Rotary kiln Slumping motion Axial segregation pSD Mean residence time

The sexually dimorphic expression of glutamate transporters and their implication in pain after spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer M.Colón-Mercado Aranza I.Torrado-Tapias Iris K.Salgado Jose M.Santiago Samuel E.Ocasio Rivera Dina p.Bracho-Rincon Luis H.pagan Rivera Jorge D.Miranda Department of physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National Institutes of Health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of puerto Rico Carolina CampusCarolinaPRUSA Institute of Neurobiology San JuanPRUSA

In addition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability and *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male and female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** and female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments and the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter and excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain EAAT-1/GLAST EAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma

Effect of Cold Deformation on phase Evolution and Mechanical properties in an Austenitic Stainless Steel for Structural and Safety Applications

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Journal of Iron and Steel Research International 2012年第4期19卷 63-68页

作者： S K Ghosh p Mallick p p Chattopadhyay Department of Metallurgy and Materials Engineering Bengal Engineering and Science UniversityShibpurHowrah 711 103India

The effects of cold deformation on the formation of strain induced α’ martensite and mechanical properties of an austenitic stainless steel have been examined.X-ray diffraction analysis has revealed that 30% and 40% cold rolling have resulted in the formation of 24% and 31.5% martensite *** investigation has demonstrated that the formation of martensite is enhanced with increase in the percent deformation at 0 ℃.Investigation of mechanical properties reveals that hardness,yield strength and tensile strength values increase where as percent elongation drops with increasing *** fractographic observation corroborates the tensile *** of sub-surface at the fractured end of the tensile sample manifests that void/microcrack nucleation occurs in the interfacial regions of the martensite phase as well as at the austenite-martensite interface

关键词： austenitic stainless steel cold deformation martensite mechanical property

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论湘渝黔边区民族文化旅游区的建立

经济地理 2004年第1期24卷 119-123页

作者：刘沛林 Geoff wall 张玉冰衡阳师范学院资源环境与旅游管理系中国湖南衡阳421008 滑铁卢大学环境研究学院

湘渝黔边区是指以传统的"武陵山区"为核心区域的3省邻近地区,大致包括湖南境内的张家界市、湘西州、怀化市,重庆的黔江区,贵州的铜仁地区和黔东南州等6个地州市,是苗族、土家族、侗族等少数民族集中聚居区,也是全国典型的老、少、边、... 详细信息

湘渝黔边区是指以传统的"武陵山区"为核心区域的3省邻近地区,大致包括湖南境内的张家界市、湘西州、怀化市,重庆的黔江区,贵州的铜仁地区和黔东南州等6个地州市,是苗族、土家族、侗族等少数民族集中聚居区,也是全国典型的老、少、边、穷山区,归属于国家"西部地区"。区域文化上的趋同性、区域旅游资源上的互补性、区域脱贫任务的紧迫性和区域旅游开发的无序性,使湘渝黔边区民族文化旅游区的建立显得十分必要。同时,具备一定基础的旅游开发现状、逐步形成的区域旅游交通网络、各地政府关于旅游业发展认识上的渐趋统一以及区域旅游中心的初步形成,使湘渝黔边区民族文化旅游区的发展成为可能。湘渝黔边区民族文化旅游区的形成,必须着手进行以下工作:迅速编制总体规划,完善旅游交通网络,建立旅游环线,推出区际旅游联合体和共同市场,多渠道吸纳资金,建立特色文化保护区等。

关键词：民族文化旅游区湘渝黔边区湖南重庆贵州旅游资源旅游开发生态博物馆特色文化保护区

Structural and physical property Analysis of ZnO-SnO_2—In_2O_3—Ga_2O_3 Quaternary Transparent Conducting Oxide System

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Journal of Materials Science & Technology 2013年第5期29卷 419-422页

作者： p.Jayaram T.p.Jaya Smagul Zh.Karazhanov p.p.pradyumnan Department of physics University of CalicutCalicut University(P.O.)Malappuram DistrictKerala 673 635India Department for Solar Energy Institute for Energy TechnologyInstituttveien 182027 KjellerNorway

The increasing demand in the diverse device applications of transparent conducting oxides （TCOs） requires synthesis of new TCOs of n- or p-type conductivity. This article is about materials engineering of ZnO-SnO2- In2O3-Ga2O3 to synthesize powders of the quaternary compound Zn2-xSn1-xlnxGaxO4-δ in the stoichiometry of x = 0.2, 0.3, and 0.4 by solid state reaction at 1275℃. Lattice parameters were determined by X-ray diffraction （XRD） technique and solubility of In3＋ and Ga3＋ in spinel Zn2SnO4 was found at 1275℃. The solubility limit of In3＋ and Ga3＋ in Zn2SnO4 is found at below x = 0.4. The optical transmittance approximated by the UV-Vis reflectance spectra showed excellent characteristics while optical band gap was consistent across 3.2 eV with slight decrease along increasing x value. Carrier mobility of the species was considerably higher than the older versions of zinc stannate spinel co-substitutions whereas the carrier concentrations were moderate.

关键词： Transparent conducting oxides (TCOs) Structural studies Mobility Optical properties

Uranium Bio-Transformations: Chemical or Biological processes?

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Open Journal of Inorganic Chemistry 2017年第2期7卷 28-60页

作者： Erica L.-W. Majumder Judy D. wall Department of Biochemistry University of Missouri Columbia MO USA

Uranium bio-transformations are the many and varying types of interactions that microbes can have with uranium encountered in their environment. In this review, bio-transformations, including reduction, oxidation, respiration, sorption, mineralization, accumulation, precipitation, biomarkers, and sensors are defined and discussed. Consensus and divergences are noted in bioavailability, mechanism of uranium reduction, environment, metabolism and the type of organism. The breadth of organisms with characterized bio-trans formations is also cataloged and discussed. We further debate if uranium biotransformations provide bio-protection or bio-benefit to the microbe and highlight the need for more work in the field to understand if microbes use uranium reduction for energy gain and growth, as having the ability is separate from exercising it. The presentation centers on the fundamental drivers for these processes with an additional exposition of the essential contribution of inorganic chemistry techniques to the molecular characterization of these biological processes.

关键词： Uranium Reduction Bio-Sorption proteobacteria

DENOISING AND HARMONIC DETECTION USING NONORTHOGONAL WAVELET pACKETS IN INDUSTRIAL AppLICATIONS

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Journal of Systems Science & Complexity 2007年第3期20卷 325-343页

作者： p.MERCORELLI Department of Vehicles Production and Process EngineeringUniversity of Applied Sciences WolfsburgRobert-Koch-Platz 8-a.38440 WolfsburgGermany.

New industrial applications call for new methods and new ideas in signal analysis. Wavelet packets are new tools in industrial applications and they have just recently appeared in projects and patents. In training neural networks, for the sake of dimensionality and of ratio of time, compact information is needed. This paper deals with simultaneous noise suppression and signal compression of quasi-harmonic signals. A quasi-harmonic signal is a signal with one dominant harmonic and some more sub harmonics in superposition. Such signals often occur in rail vehicle systems, in which noisy signals are present. Typically, they are signals which come from rail overhead power lines and are generated by intermodulation phenomena and radio interferences. An important task is to monitor and recognize them. This paper proposes an algorithm to differentiate discrete signals from their noisy observations using a library of nonorthonormal bases. The algorithm combines the shrinkage technique and techniques in regression analysis using Shannon Entropy function and Cross Entropy function to select the best discernable bases. Cosine and sine wavelet bases in wavelet packets are used. The algorithm is totally general and can be used in many industrial applications. The effectiveness of the proposed method consists of using as few as possible samples of the measured signal and in the meantime highlighting the difference between the noise and the desired signal. The problem is a difficult one, but well posed. In fact, compression reduces the level of the measured noise and undesired signals but introduces the well known compression noise. The goal is to extract a coherent signal from the measured signal which will be ＂well represented＂ by suitable waveforms and a noisy signal or incoherent signal which cannot be ＂compressed well＂ by the waveforms. Recursive residual iterations with cosine and sine bases allow the extraction of elements of the required signal and the noise. The algorithm

关键词： Data compression denoising rail vehicle control trigonometric bases wavelet packets.

Throughflow and g-jitter effects on binary fluid saturated porous medium

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Applied Mathematics and Mechanics(English Edition) 2015年第10期36卷 1285-1304页

作者： p.KIRAN Department of Applied Mathematics School for Physical Sciences Babasaheb Bhimrao Ambedkar University

A non-autonomous complex Ginzburg-Landau equation （CGLE） for the finite amplitude of convection is derived, and a method is presented here to determine the amplitude of this convection with a weakly nonlinear thermal instability for an oscillatory mode under throughflow and gravity modulation. Only infinitesimal disturbances are considered. The disturbances in velocity, temperature, and solutal fields are treated by a perturbation expansion in powers of the amplitude of the applied gravity field. Throughfiow can stabilize or destabilize the system for stress free and isothermal boundary conditions. The Nusselt and Sherwood numbers are obtained numerically to present the results of heat and mass transfer. It is found that throughfiow and gravity modulation can be used alternately to heat and mass transfer. Further, oscillatory flow, rather than stationary flow, enhances heat and mass transfer.

关键词： weakly nonlinear theory throughflow complex Ginzburg-Landau equation(CGLE) gravity modulation