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A comparative evaluation of microstructural and mechanical behavior of fiber laser beam and tungsten inert gas dissimilar ultra high strength steel welds

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Defence Technology（防务技术） 2016年第6期12卷 464-472页

作者： Jaiteerth r. JOSHI Mastanaiah POTTA Kumar ADEPU ramesh Kumar KATTA Madhusudhan reddy GANKIDI Defence research and Development Laboratory Kanchanbagh Hyderabad Telangana 500058 India National Institute of Technology Warangal Telangana 502205 India Defence Metallurgical research Laboratory Kanchanbagh Hyderabad Telangana 500058 India

The influence of different welding processes on the mechanical properties and the corresponding variation in the microstructural features have been investigated for the dissimilar weldments of 18% Ni maraging steel 250 and AISI 4130 steel. The weld joints are realized through two different fusion welding processes, tungsten inert arc welding(TIG) and laser beam welding(LBW), in this study. The dissimilar steel welds were characterized through optical microstructures, microhardness survey across the weldment and evaluation of tensile properties. The fiber laser beam welds have demonstrated superior mechanical properties and reduced heat affected zone as compared to the TIG weldments.

关键词： TIG welding Fiber laser AISI 4130 steel Laser beam welding Maraging steel

Influence of isovector pairing and particle-number projection effects on spectroscopic factors for one-pair like-particle transfer reactions in proton-rich even-even nuclei

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Chinese Physics C 2018年第4期42卷 171-187页

作者： Y.Benbouzid N.H.Allal M.Fellah M.r.Oudih Laboratoire de Physique Theorique-Faculte de Physique-USTHB BP32 El-Alia16111 Bab-EzzouarAlgerAlgeria

Isovector neutron-proton（np） pairing and particle-number fluctuation effects on the spectroscopic factors（SF） corresponding to one-pair like-particle transfer reactions in proton-rich even-even nuclei are studied. With this aim, expressions of the SF corresponding to two-neutron stripping and two-proton pick-up reactions, which take into account the isovector np pairing effect, are established within the generalized BCS approach, using a schematic definition proposed by Chasman. Expressions of the same SF which strictly conserve the particle number are also established within the Sharp-BCS（SBCS） discrete projection method. In both cases, it is shown that these expressions generalize those obtained when only the pairing between like particles is considered. First, the formalism is tested within the richardson schematic model. Second, it is applied to study even-even proton-rich nuclei using the single-particle energies of a Woods-Saxon mean-field. In both cases, it is shown that the np pairing effect and the particle-number projection effect on the SF values are important, particularly in N =Z nuclei, and must then be taken into account.

关键词： neutron-proton pairing particle-number fluctuations spectroscopic factor

A New Modified GM (1,1) Model: Grey Optimization Model

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Journal of Systems Engineering and Electronics 2001年第2期12卷 1-5页

作者： Xiao Xinping College of Scienced, Wuhan University of Technologyl 430063, P r. China Deng Julong Dept. of Control, Huazhong University of Science and Technology, Wuhan 430074,P. r. China College of Sciences Wuhan University of Technology 430063 P. R. China Dept. of Control Huazhong University of Science and Technology Wuhan 430074 P. R. China

Based on the optimization method, a new modified GM (1,1) model is presented, which is characterized by more accuracy prediction for the grey modeling.

关键词： GM (1,1) Grey optimization model Optimization method.

Generalized Linear Model with Elastic Net regularization and Convolutional Neural Network for Evaluating Aphanomyces root rot Severity in Lentil

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Plant Phenomics 2020年第1期2卷 378-388页

作者： Afef Marzougui Yu Ma rebecca J.McGee Lav r.Khot Sindhuja Sankaran Department of Biological Systems Engineering Washington State UniversityPullmanWAUSA Department of Horticulture Washington State UniversityPullmanWAUSA United States Department of Agriculture-Agricultural research Service Grain Legume Genetics and Physiology Research UnitWashington State UniversityPullmanWAUSA

Phenomics technologies allow quantitative assessment of phenotypes across a larger number of plant genotypes compared to traditional phenotyping *** utilization of such technologies has enabled the generation of multidimensional plant traits creating big ***,to harness the power of phenomics technologies,more sophisticated data analysis methods are *** this study,Aphanomyces root rot(Arr)resistance in 547 lentil accessions and lines was evaluated using red-Green-Blue(rGB)images of *** created a dataset of 6,460 root images that were annotated by a plant breeder based on the disease *** approaches,generalized linear model with elastic net regularization(EN)and convolutional neural network(CNN),were developed to classify disease resistance categories into three classes:resistant,partially resistant,and *** results indicated that the selected image features using EN models were able to classify three disease categories with an accuracy of up to 0:91±0:004(0:96±0:005 resistant,0:82±0:009 partially resistant,and 0:92±0:007 susceptible)compared to CNN with an accuracy of about 0:84±0:009(0:96±0:008 resistant,0:68±0:026 partially resistant,and 0:83±0:015 susceptible).The resistant class was accurately detected using both classification ***,partially resistant class was challenging to detect as the features(data)of the partially resistant class often overlapped with those of resistant and susceptible ***,the findings provided insights on the use of phenomics techniques and machine learning approaches to provide quantitative measures of Arr resistance in lentil.

关键词： classify Elastic roots

Intrinsic ferromagnetism in CoBr2 nanolayers:a DFT+U and Monte Carlo study

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Communications in Theoretical Physics 2021年第11期73卷 165-170页

作者： A Jabar r Masrour G Kadim M Hamedoun A Hourmatallah N Benzakour A rezzouk K Bouslykhane J Kharbach Laboratory of Solid Physics Faculty of Sciences Dhar El MahrazSidi Mohamed Ben Abdellah UniversityBP 1796FezMorocco MAScIr Institute of Nanomaterials and NanotechnologiesRabatMorocco Equipe de Physique du Solide Laboratoire LIPIEcole Normale SupérieureBensoudaBP 5206FèsMorocco

The intrinsic ferromagnetism of CoBr2 bulk was investigated using DFT(density functional theory)combined with the full potential linear augmented plane wave method and Monte Carlo *** ground state of CoBr2 exhibits ferromagnetic behavior and a semiconductor *** used the generalized gradient approximation(GGA)and GGA+U(Hubbard correction)approximations to determinate the magnetic *** magnetic moment reached the experimental value and was in good agreement with the other theoretical *** value obtained was used as an input to a Monte Carlo study to calculate the thermal magnetization and magnetic hysteresis *** behavior was observed and was found to be due to an positive exchange *** results lead us to believe that this material could be a promising spintronic material.

关键词： CoBr2 nanolayer DFT Monte Carlo transition temperature magnetic hysteresis cycles

Finite Groups in Which Sylow Normalizers Admit Supplements

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Acta Mathematica Sinica,English Series 2007年第3期23卷 417-422页

作者： Tian Ze LI School of Mathematical Sciences,Peking University,Beijing 100871,P.r.China School of Mathematical Sciences Peking University Beijing 100871 P. R. China

For a group G and a subgroup M of G,we say that a subgroup A of G is a supplement toM in G,if G=*** prove that a finite group in which every Sylow normalizer admits a nilpotentsupplement is *** particular we confirm a... 详细信息

关键词： Sylow normalizer Supplement Wreath product

PrEDICTION OF THE GrAIN SIZE OF SUSPENDED SEDIMENT:IMPLICATIONS FOr CALCULATING SUSPENDED SEDIMENT CONCENTrATIONS USING SINGLE FrEQUENCY ACOUSTIC BACKSCATTEr

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International Journal of Sediment research 2007年第1期22卷 1-15页

作者： r. A. KUHNLE D. G. WrEN J. P. CHAMBErS Dr.research Hydraulic Engineer National Sedimentation Laboratory U. S. Department of Agriculture Agricultural Research Service Oxford Mississippi 38655 USA Senior research Scientist National Center for Physical Acoustics University of Mississippi University Mississippi 38677 USA

Collection of samples of suspended sediment transported by streams and rivers is difficult and expensive. Emerging technologies, such as acoustic backscatter, have promise to decrease costs and allow more thorough sampling of transported sediment in streams and rivers. Acoustic backscatter information may be used to calculate the concentration of suspended sand-sized sediment given the vertical distribution of sediment size. Therefore, procedures to accurately compute suspended sediment size distributions from easily obtained river data are badly needed. In this study, techniques to predict the size of suspended sand are examined and their application to measuring concentrations using acoustic backscatter data are explored. Three methods to predict the size of sediment in suspension using bed sediment, flow criteria, and a modified form of the rouse equation yielded mean suspended sediment sizes that differed from means of measured data by 7 to 50 percent. When one sample near the bed was used as a reference, mean error was reduced to about 5 percent. These errors in size determination translate into errors of 7 to 156 percent in the prediction of sediment concentration using backscatter data from 1 MHz single frequency acoustics.

关键词： Suspended sediment Grain size Acoustic backscatter Concentration errors

Comparative transcriptomics of anadromous and resident brook charr Salvelinus fontinalis before their first salt water transition

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Current Zoology 2012年第1期58卷 158-170页

作者： Boulet, Marylène Normandeau, Éric Bougas, Bérénice Audet, Céline Bernatchez, Louis IBIS (Institut de Biologie Intégrative et des Systèmes) Université Laval Québec QC G1V 0A6 Canada ISMEr Université du Québec à Rimouski Rimouski QC G5L 3A1 Canada

Most salmonid taxa have an anadromous life history strategy, whereby fish migrate to saltwater habitats for a growth period before returning to freshwater habitats for spawning. Moreover, several species are characterized by different life history tactics whereby resident and anadromous forms may occur in genetically differentiated populations within a same species, as well as polymorphism within a population. The molecular mechanisms underlying the physiological differences between anadromous and resident forms during the first transition from freshwater to saltwater environments are only partially understood. Insofar re- search has typically focused on species of the genus Salmo. Here, using a 16,000 cDNA array, we tested the hypothesis that ana- dromous brook charr Salvelinus fontinalis are characterized by differences in their transcriptome relative to resident brook charr before the anadromous fish migration. Families originating from parapatric populations of anadromous and resident charr were reared in controlled environments mimicking natural temperature and photoperiod, and sampled in spring, while still in fresh wa- ter. While anadromous and resident charr showed similar transcriptome profiles in white muscle, they were characterized by striking differences in their gill transcriptome profiles. Genes that were upregulated in the gills of anadromous charr were princi- pally involved in metabolism （mitochondrial electron transport chain, glucose metabolism, and protein synthesis）, development （tissue differentiation） and innate immunity. We discuss the nature of these transcriptomic differences in relation to molecular mechanisms underlying the expression of anadromous and resident life history tactics and suggest that the anadromous charr express some of the molecular processes present in other migratory salmonids [Current Zoology 58 （1）： 158-170, 2012].

关键词： Transcriptome Life history tactics Anadromy Migration to salt water Ecotypes Salmohids

Transcriptome Analysis of Arabidopsis Wild-Type and gl3-sst sim Trichomes Identifies Four Additional Genes required for Trichome Development

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Molecular Plant 2009年第4期2卷 803-822页

作者： M. David Marks Jonathan r Wenger Edward Gilding ross Jilk richard A. Dixon Department of Plant Biology University of Minnesota St Paul MN 551108 USA Department of Chemistry University of Wisconsin-River Falls River Falls Wl 54022 USA Plant Biology Division Samuel Roberts Noble Foundation Ardmore OK 73401 USA

Transcriptome analyses have been performed on mature trichomes isolated from wild-type Arabidopsis leaves and on leaf trichomes isolated from the g13-sst sim double mutant, which exhibit many attributes of immature trichomes. The mature trichome profile contained many highly expressed genes involved in cell wall synthesis, protein turnover, and abiotic stress response. The most highly expressed genes in the g13-sst sim profile encoded ribosomal proteins and other proteins involved in translation. Comparative analyses showed that all but one of the genes encoding transcription factors previously found to be important for trichome formation, and many other trichome-important genes, were preferentially expressed in gl3-sst sim trichomes. The analysis of genes preferentially expressed in gl3-sst sim led to the identification of four additional genes required for normal trichome development. One of these was the HDG2 gene, which is a member of the HD-ZIP IV transcription factor gene family. Mutations in this gene did not alter trichome expansion, but did alter mature trichome cell walls. Mutations in BIT resulted in a loss of trichome branch formation. The relationship between bit and the phenotypically identical mutant, sti, was explored. Mutations in PEL3, which was previously shown to be required for development of the leaf cuticle, resulted in the occasional tangling of expanding trichomes. Mutations in another gene encoding a protein with an unknown function altered trichome branch formation.

关键词： Cell wall cell differentiation homeodomain wax trichome