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A combination of damage locating vector method （DLv） and differential evolution algorithm （DE） for structural damage assessment

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Frontiers of Structural and Civil Engineering 2018年第1期12卷 92-108页

作者： t. NGUYEN-tHOI A. tRAN-vIEt N. NGUYEN-MINH t. vO-DUY v. HO-HUU Division of Computational Mathematics and Engineering Institute for Computational Science Ton Duc Thang University Hochiminh City Vietnam Division of Construction Computation Institute for Computational Science Ton Duc Thang University Hochiminh City Vietnam Faculty of Civil Engineering Ton Duc Thang University Hochiminh City Vietnam

In this study, a two-stage method is presented for identifying multiple damage scenarios. In the first stage, the damage locating vector （DLv） method using normalized cumulative energy （nce） is employed for damage localization in structures. In the second stage, the differential evolution algorithm （DE） is used for damage severity of the structures. In addition, in the second stage, a modification of an available objective function is made for handing the issue of symmetric structures. to verify the effectiveness of the present technique, numerical examples of a 72-bar space truss and a one-span steel portal frame are considered. In addition, the effect of noise on the performance of the identification results is also investigated. the numerical results show that the proposed combination gives good assessment of damage location and extent for multiple structural damage cases.

关键词： damage assessment damage locating vector method (DLv) differential evolution (DE) multiple damagelocation assurance criterion (MDLAC) mode shape error function

Microstructure, properties and hot workability of M300 grade maraging steel

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Defence technology（防务技术） 2018年第1期14卷 51-58页

作者： K.v.A.Chakravarthi N.t.B.N.Koundinya S.v.S.Narayana Murty B.Nageswara Rao Materials and Mechanical Entity Vikram Sarabhai Space Centre Research scholar Department of Mechanical Engineering K L University Department of Metallurgical Engineering and Materials Science Indian Institute of Technology Department of Mechanical Engineering K L University

this paper presents isothermal uniaxial compression test results of M300 grade maraging steel over a wide range of temperatures(900 e1200℃) and strain rates(0.001 e100 s^(-1)) to examine hot deformability and concurrent microstructural evolution. Processing map is generated and indicated the optimum processing parameters in the temperature range of 1125℃-1200℃ and strain rate range of 0.001 e0.1 s^(-1). High values of the efficiency of power dissipation, microstructural observations and EBSD results indicate softening mechanism to be the occurrence of dynamic recrystallisation. Material constants in a constitutive relation are evaluated from the flow stress data useful in computer modelling.

关键词： Activation energy Constitutive relation Hot deformation M300 grade maraging steel Processing map

Cell Wall Lignin is Polymerised by Class Ⅲ Secretable Plant Peroxidases in Norway Spruce

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Journal of Integrative Plant Biology 2010年第2期52卷 186-194页

作者： Kurt v.Fagerstedt Eija M.Kukkola ville v.t.Koistinen Junko takahashi Kaisa Marjamaa Department of Biological and Environmental Sciences Plant BiologyP.O. Box 65 FI-00014 Helsinki UniversityFinland technical Research Center of Finland (vtt) PL 100002044 VTTFinland

Class Ⅲ secretable plant peroxidases occur as a large family of genes in plants with many functions and probable redundancy. In this review we are concentrating on the evidence we have on the catalysis of lignin polymerization by class Ⅲ plant peroxidases present in the apoplastic space in the xylem of trees. Some evidence exists on the specificity of peroxidase isozymes in lignin polymerization through substrate specificity studies, from antisense mutants in tobacco and poplar and from tissue and cell culture lines of Norway spruce （Picea abies） and Zinnia elegans. In addition, real time （Rt-）PCR results have pointed out that many peroxidases have tissue specific expression patterns in Norway spruce. through combining information on catalytic properties of the enzymes, on the expression patterns of the corresponding genes, and on the presence of monolignols and hydrogen peroxide in the apoplastic space, we can show that specific peroxidases catalyze lignin polymerization in the apoplastic space of Norway spruce xylem.

关键词： Secretable Plant Peroxidases in Norway Spruce

Siberian silkmoth outbreaks surpassed geoclimatic barrier in Siberian Mountains

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Journal of Mountain Science 2020年第8期17卷 1891-1900页

作者： KHARUK viacheslav I. IM Sergei t. SOLDAtOv vladimir v. Sukachev Institute of Forest Federal Scientific CenterRussian Academy of ScienceSiberian BranchAcademgorodok 50/28Krasnoyarsk660036 Russia Siberian Federal University Svobodny str.79Krasnoyarsk660041 Russia Reshetnev Siberian State University of Science and technology Krasnoyarsky rabochy str.31Krasnoyarsk660014 Russia Russian Center of Forest Protection Academgorodok 50A/2Krasnoyarsk660036 Russia

Siberian silkmoth(SSM,Dendrolimus sibiricus tschetv.)is the most important defoliator of Siberian pine(Pinus sibirica Du tour)and fir(Abies sibirica Ledeb.)***-induced SSM outbreaks are one of the major driving factors of successions within the taiga *** is suggested that climate change impacted the SSM range and life *** analyzed the migration of alpine and northerly SSM outbreak boundaries in Siberia and the impact of the climate variables and topography on the outbreak *** used time-series scenes(multispectral data,and vegetation indexes EvI and NDII)in combination with field studies,climate variables,and GIS *** found that SSM outbreaks in the area of alpine boundary shifted about 370 m uphill since the mid of *** outbreak onset was promoted by increased dryness and active temperatures and decreased root zone moisture content in the spring-early summer *** terrain topography strongly affected SSM outbreak onset and ***,the outbreak was located at the middle elevations on the gentle concave southeastern slopes,which are the favorable insect habitats between *** the outbreak expanded uphill and downhill,to steeper slopes,and both concave and convex *** with elevation range expansion,SSM surpassed its northern historical outbreak boundary:the potential outbreaks’boundary moved about 300 km *** warming contributes to SSM migration into former outbreak free conifer stands located in highlands and at northern latitudes.

关键词： Insect outbreaks Remote sensing monitoring Insect ranges expansion Siberian silkmoth Forest health Conifer mortality

Combined heat and power economic dispatch problem using the invasive weed optimization algorithm

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Frontiers in Energy 2014年第1期8卷 25-30页

作者： t. JAYABARAtHI Afshin YAZDANI v. RAMESI t. RAGHUNAtHAN School of Electrical En~ineerinz VIT University Vellore 632014 India

Cogeneration units which produce both heat and electric power are found in many process industries. these industries also consume heat directly in addition to electricity. the cogeneration units operate only within a feasible zone. Each point within the feasible zone consists of a specific value of heat and electric power. these units are used along with other units which produce either heat or power exclusively. Hence the economic dispatch problem for these plants optimizing the fuel cost is quite complex and several classical and meta-heuristic algo- rithms have been proposed earlier. this paper applies the invasive weed optimization algorithm which is inspired by the ecological process of weed colonization and distribu- tion. the results obtained have been compared with those obtained by other methods earlier and showed a marked improvement over earlier ones.

关键词： combined heat and power (CHP) economicdispatch meta-heuristic algorithm invasive weed optimiza-tion cogeneration

Combined heat and power economic dispatch problem using firefly algorithm

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Frontiers in Energy 2013年第2期7卷 133-139页

作者： Afshin YAZDANI t. JAYABARAtHI v. RAMESH t. RAGHUNAtHAN School of Electrical Engineering VIT University Vellore 632014 India

Cogeneration units, which produce both heat and electric power, are found in many process industries. these industries also consume heat directly in addition to electricity. the cogeneration units operate only within a feasible zone. Each point within the feasible zone consists of a specific value of heat and electric power. these units are used along with other units, which produce either heat or power exclusively. Hence, the economic dispatch problem for these plants to optimize the fuel cost is quite complex and several classical and meta-heuristic algo- rithms have been proposed earlier. this paper applies the firefly algorithm, which is inspired by the behavior of fireflies which attract each other based on their luminosity. the results obtained have been compared with those obtained by other methods earlier and showed a marked improvement over the earlier methods.

关键词： combined heat and power (CHP) economicdispatch meta-heuristic algorithm firefly algorithm cogen-eration

Effect of vanadium and chromium on the microstructural features of v–Cr–Mn–Ni spheroidal carbide cast irons

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International Journal of Minerals,Metallurgy and Materials 2014年第11期21卷 1096-1108页

作者： v.G.Efremenko K.Shimizu A.P.Cheiliakh t.v.Kozarevskaya K.Kusumoto K.Yamamoto Department of Metal Science and Heat treatment of Metals Pryazovskyi State Technical UniversityMariupol 87500 Ukraine Manufacturing and Engineering Design Center Muroran Institute of TechnologyMuroran 050-8585 Japan

the objective of this investigation is to study the influence of vanadium（5.0wt%–10.0wt%） and chromium（0–9.0wt%） on the microstructure and hardness of Cr-v-Mn-Ni white cast irons with spheroidal vanadium carbides. the alloys＇ microstructural features are presented and discussed with regard to the distribution of phase elements. the structural constituents of the alloys are spheroidal vC, proeutectoid cementite, ledeburite eutectic, rosette-shaped carbide eutectic（based on M7C3）, pearlite, martensite, and austenite. their combinations and area fraction（AF） ratios are reported to be influenced by the alloys＇ chemical composition. Spheroidized vC particles are found to be sites for the nucleation of carbide eutectics. Cr and v are shown to substitute each other in the vC and M7C3 carbides, respectively. Chromium alloying leads to the formation of a eutectic（γ-Fe ＋ М7С3）, preventing the appearance of proeutectoid cementite in the structure. vanadium and chromium are revealed to increase the total carbide fraction and the amount of austenite in the matrix. Cr is observed to play a key role in controlling the metallic matrix microstructure.

关键词： cast irons carbides microstructure vanadium chromium austenite pearlite

Dreicer Electric Field Definition and Runaway Electrons in Solar Flares

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Research in Astronomy and Astrophysics 2024年第2期24卷 180-184页

作者： Yu.t.tsap A.v.Stepanov Yu.G.Kopylova Crimean Astrophysical Observatory of the Russian Academy of Sciences Nauchny298409Russia Pulkovo Observatory of the Russian Academy of Sciences Pulkovskoje Shosse65/1St.Petersburg196140Russia

We analyze electron acceleration by a large-scale electric field E in a collisional hydrogen plasma under the solar flare coronal conditions based on approaches proposed by Dreicer and Spitzer for the dynamic friction force of *** Dreicer electric field EDr is determined as a critical electric field at which the entire electron population runs *** regimes of strong(E≲E_(Dr))and weak(E≪E_(Dr))electric field are *** is shown that the commonly used formal definition of the Dreicer field leads to an overestimation of its value by about five *** critical velocity at which the electrons of the"tail"of the Maxwell distribution become runaway under the action of the sub-Dreiser electric fields turns out to be underestimated by√3 times in some works because the Coulomb collisions between runaway and thermal electrons are not taken into *** electron acceleration by sub-Dreicer electric fields generated in the solar corona faces difficulties.

关键词： acceleration of particles-Sun flares-Physical Data and Processes

A 96-antenna radioheliograph

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Research in Astronomy and Astrophysics 2014年第7期14卷 864-868页

作者： Sergey v.Lesovoi Alexander t.Altyntsev Eugene F.Ivanov Alexey v.Gubin Institute of Solar-terrestrial Physics

Here we briefly present some design approaches for a multifrequency 96-antenna radioheliograph. the configuration of the array antenna, transmission lines and digital receivers is the main focus of this work. the radioheliograph is a t-shaped centrally condensed radiointerferometer operating in the frequency range 4–8 *** justification for the choice of such a configuration is discussed. the signals from antennas are transmitted to a workroom by analog optical links. the dynamic range and phase errors of the microwave-over-optical signal are considered. the signals after downconverting are processed by digital receivers for delay tracking and fringe stopping. the required step of delay tracking and data rates are considered. two 3-bit data streams（I and Q） are transmitted to a correlator with the transceivers embedded in Field Programmed Gate Array chips and with PCI Express cables.

关键词： telescopes -- instrumentation: interferometers -- Sun: radio radiation