检索结果-南通市图书馆

STABiLiTY OF A VON kARMAN EQUATiON WiTH iNFiNiTE MEMORY

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Scientia 2017年第4期37卷 965-973页

作者： Sun-Hye park Center for Education Accreditation Pusan National UniversityBusan 609-735South Korea

in this paper, we consider a von karman equation with infinite memory. For yon karman equations with finite memory, there is a lot of literature concerning on existence of the solutions, decay of the energy, and existence of the attractors. However, there are few results on existence and energy decay rate of the solutions for yon karman equations with infinite memory. The main goal of the present paper is to generalize previous results by treating infinite history instead of finite history.

关键词： yon karman equation general decay infinite memory

Universal Jensen's Equations in Banach Modules over a C-Algebra and its Unitary Group

在线全文

学校读者我要写书评

暂无评论

Acta Mathematica Sinica,English Series 2004年第6期20卷 1047-1056页

作者： Chun Gil park Department of Mathematics Chungnam National University

in this paper,we prove the generalized Hyers-Ulam-Rassias stability of universal Jensen's equations in Banach modules over a unital C~*-*** is applied to show the stability of universal Jensen's equations in a Hilbert module over a unital C~*-***,we prove the stability of linear operators in a Hilbert module over a unitat C~*-algebra.

关键词： Banach module over C~*-algebra Universal Jensen's equation Stability Hilbert module over C~*-algebra Real rank O Unitary group

Extended X-ray absorption fine structure (EXAFS) of FAPbi_(3) for understanding local structure-stability relation in perovskite solar cells

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 2022年第4期31卷 549-554页

作者： Dong-Ho kang Yong-Jun park Yun-Sung Jeon Nam-Gyu park School of Chemical Engineering and Center for Antibonding Regulated Crystals Sungkyunkwan UniversitySuwon 16419Korea

Perovskite solar cells (PSCs) employing formamidinium lead iodide (FAPbi_(3)) have shown high ***,operational stability has been issued due to phase instability of α phase FAPbi_(3) at ambient *** precursors in the perovskite precursor solution has been proposed to improve not only power conversion efficiency (PCE) but also device ***,there is a controversial issue on the beneficial effect on PCE and/or stability between excess FAi and excess Pbi_(2).We report here extended X-ray absorption fine structure (EXAFS) of FAPbi_(3) to study local structural change and explain the effect of excess precursors on photovoltaic performance and *** films prepared from the precursor solution with excess Pbi_(2)shows better stability than those from the one with excess FAi,despite similar PCE.A rapid phase transition from α phase to non-perovskite δ phase is observed from the perovskite film formed by excess ***,the (Pb-i) bond distance evaluated by the Pb L_(iii)-edge EXAFS study is increased by excess FAi,which is responsible for the phase transition and poor device *** work can provide important insight into local structure-stability relation in the FAPbi_(3)-based PSCs.

关键词： Extended X-ray absorption fine structure EXAFS Excess precursor Local structure Stability Perovskite solar cells

Amine functionalization on thermal and mechanical behaviors of graphite nanofibers-loaded epoxy composites

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2023年第20期151卷 80-88页

作者： Seong-Hwang kim Sang-Jin park Seul-Yi Lee Soo-Jin park Department of Chemistry Inha University100 InharoIncheon 22212the Republic of Korea

With the growing demand for faster and more powerful computing,effective heat dissipation is essential to ensure the longevity,reliability,and high performance of electronic *** the field of modern electronic packaging materials,there is a great need for graphitic material-loaded polymeric composites(GPCs)with excellent thermal ***,the enhancement efficiency of GPCs is hindered by the agglomeration of fillers and the interfacial thermal resistance caused by the lack of continuous thermally conductive pathways between the filler and *** the interfaces between filler and matrix is of great importance in optimizing the performances of ***,we fabricated graphite nanofibers(GNF)-loaded nanocomposites using acid-functionalized GNF(AGNF)and acidtetraethylenepentamine-functionalized(TGNF)as a filler and epoxy resin as a matrix with different GNF loading contents to explore the interfacial properties of the *** optimal GNF loading for AGNF was 0.5 wt.%,while the TGNF showed 0.75 wt.%.The highest thermal conductivity(0.51 W m^(−1) k^(−1))and fracture toughness(25.8 MPa m^(1/2))values were found in the TGNF-loaded nanocomposites with a fraction of 0.75 wt.%,representing enhancements of∼145%and∼400%,respectively,compared to those of neat *** experimental data presented herein demonstrate that the interfacial properties play a significant role in enhancing the thermal and mechanical performances of the *** present approach is expected to serve as a valuable tool in the design of conductive polymeric nanocomposites for further practical applications,such as thermal interface materials and packaging of high-power electric devices.

关键词： Graphite nanofiber Nanocomposites interfacial interaction Thermal conductivity Fracture resistance

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第26期85卷 95-105页

作者： Nana kwabena Adomako Giseung Shin Nokeun park kyoungtae park Jeoung Han kim Department of Materials Science and Engineering Hanbat National UniversityYuseong-guDaejeon34158Republic of Korea Department of Materials Science and Engineering Pusan National UniversityGeumjeong-guBusan46241Republic of Korea School of Materials Science and Engineering Yeungnam University280 Daehak-roGyeongbuk38541Republic of Korea Rare Metal R&D Group Korea Institute of Industrial TechnologyIncheon21999Republic of Korea

High entropy alloys(HEAs)have superior mechanical properties that have enabled them to be used as structural materials in nuclear and aerospace *** a dissimilar joint design is required for these applications,we created a dissimilar joint between CoCrFeMnNi-HEA and duplex stainless steel(DSS)through laser beam welding;a technique capable of producing a sound joint between the two *** structure examination using SEM/EBSD/XRD analysis revealed that the weld metal(WM)exhibits an FCC phase regardless of the postweld heat treatment(PWHT)temperature(800 and 1000℃)without forming detrimental intermetallic compounds or *** heat-affected zone of the CoCrFeMnNi-HEA showed CrMn oxide inclusions while that of the DSS showed no ***,a lower hardness was recorded by the WM compared to the base metal after *** PWHT,the hardness of the WM,CoCrFeMnNi-HEA,and DSS decreased with an increase in the PWHT ***,the decrease in the hardness of the HEA was more significant than in the WM and *** cause for this reduction in hardness was attributed to recrystallization and grain *** addition,a strength of 584 MPa with low ductility was recorded after *** obtained strength was lower than that of the BMs,but comparable to that of the welded *** application of PWHT resulted in over a 20%increment in ductility,with only a marginal reduction in *** defo rmation mechanism in the as-weld joint was mainly dominated by dislocation while that for the PWHT joint was *** propose laser beam offset welding as a technique to improve the mechanical properties of the dissimilar joint,which will be the subject of future studies.

关键词： High entropy alloys Welding Duplex stainless steel Post-weld heat treatment

Room temperature hydrogen sensing performances of multiple networked Ga N nanowire sensors codecorated with Au and Pt nanoparticles

在线全文

学校读者我要写书评

暂无评论

Journal of Central South University 2015年第5期22卷 1614-1618页

作者： park Sunghoon kiM Soohyun park Suyoung LEE Sangmin LEE Chongmu Department of Materials Science and Engineering Inha University 253 Yonghyun-dong Nam-gu Incheon 402-751 Korea Department of Electronic Engineering Inha University 253 Yonghyun-dong Nam-gu Incheon 402-751 Korea

The sensing performances of multiple networked Ga N nanowire(NW) sensor codecorated with Au and Pt nanoparticles were examined. The pristine Ga N nanowires show responses of approximately 108%-173% to 0.05%-0.25% H2 at room temperature. On the other hand, the Ga N nanowires decorated with Au and those decorated with Pt lead to 1.1-1.3 and 1.2-1.6 times,respectively, stronger responses to 0.05%-0.25% H2. in contrast, the Au Pt-codecorated Ga N nanowires show 1.3-2.0 times stronger responses to 0.05%-0.25% H2. in other words, the Ga N nanorods codecorated with Au and Pt nanoparticles show much stronger response to H2 gas than the Au or Pt monometal-decorated counterpart. The underlying mechanism for the enhanced response of the Au Pt-codecorated Ga N nanowire was discussed.

关键词： Ga N nanowires metal catalyst bimetallic system gas sensor codecoration

Study of the interface between Steel insert and Aluminum Casting in EPC

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2008年第1期24卷 60-64页

作者： k.H.Choe k.S.park B.H.kang G.S.Cho k.Y.kim k.W.Lee M.H.kim A.ikenaga S.koroyasu Advanced Material Processing Team korea institute of industrial Technology IncheonKorea Department of Materials Engineering korea University of Technology and Education ChoongnamKorea Department of Materials Science and Engineering inha University IncheonKorea Department of Metallurgy and Materials Science Graduate School of Engineering Osaka Prefecture UniversityOsakaJapan Department of Mechanical and Precision Systems Teiko University UtsunomiyaJapan

The effective surface treatment method for steel insert composited with Al base metal by expendable pattern casting （EPC） process and the bonding interface between steel insert and Al base metal were *** was found that Zn plating on steel insert was effective on improving the bonding property between steel insert and Al base metal in EPC *** is thought to promote the formation of diffusion *** almost none content of Zn was observed in the boundary which had been plated on the steel insert.A diffusion layer consisting of Al,Si and Fe was formed at the insert/alloy interface and its hardness was higher than the steel insert as matter of course Al base *** layer turned out to be intermetallic compounds of Al-Si-Fe *** pouring temperature promoted the diffusion of Fe into Al alloy,so Fe content in intermetallic layers increased at higher pouring *** layer nearest to steel disappeared due to applied pressure.

关键词： Expendable pattern casting insert casting intermetallic compound Al-Si-Fesystem

Electrical Properties of Sputter-deposited ZrO2-based Pt/ZrO_2/Si Capacitors

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2006年第6期22卷 807-810页

作者： keunbin YiM Yeonkyu park Anna park Namhee CHO Chongmu LEE Department of Materials Science and Engineering Inha UniversityIncheon 402-751Korea

Pt/ZrO2/Si sandwich structures where ZrO2 is deposited by radio frequency （r.f.） magnetron sputtering using a Zr target in an atmosphere of O2/Ar gas mixture, were fabricated and the effects of the O2/Ar flow ratio in the reactive sputtering process, the annealing temperature, the ZrO2 film thickness on the structure, the surface roughness of ZrO2 films and the electric properties of Pt/ZrO2/Si metal-oxide-semiconductor （MOS） capacitors were investigated. The optimum process parameters of the Pt/ZrO2/Si capacitor based on reactively sputtered-ZrO2 determined in such a way as the capacitance is maximized and the leakage current, the oxide charge, and the interface trap density are minimized that is the O2/Ar flow ratio of 1.5, the annealing temperature of 800℃, and the film thickness of 10 nm. Also the conduction mechanism in the Pt/ZrO2/Si capacitor has been discussed.

关键词： ZrO2 Gate dielectrics Radio frequency Magnetron sputtering

Energy Aware Metaheuristic Optimization with Location Aided Routing Protocol for MANET

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2022年第4期71卷 1567-1580页

作者： E.Ahila Devi k.C.Ramya k.Sathesh kumar Sultan Ahmad Seifedine kadry Hyung Ju park Byeong-Gwon kang Department of instrumentation and Control Engineering St.Joseph’s College of EngineeringChennai600119India Department of Electrical and Electronics Engineering Sri Krishna College of Engineering and TechnologyCoimbatore641008India School of Computing Kalasalingam Academy of Research and EducationKrishnankoil626128India Department of Computer Science College of Computer Engineering and SciencesPrince Sattam Bin Abdulaziz UniversityAlkharj11942Saudi Arabia Department of Applied Data Science Noroff University CollegeKristiansand4612Norway Department of iCT Convergence Soonchunhyang UniversityAsan31538Korea

A mobile ad hoc network(MANET)involves a group of wireless mobile nodes which create an impermanent network with no central authority and *** nodes in the MANET are highly mobile and it results in adequate network topology,link loss,and increase the re-initialization of the route discovery *** planning in MANET is a multi-hop communication process due to the restricted transmission range of the *** aided routing(LAR)is one of the effective routing protocols in MANET which suffers from the issue of high energy *** few research works have focused on resolving energy consumption problem in LAR,energy efficiency still remains a major design *** this aspect,this study introduces an energy aware metaheuristic optimization with LAR(EAMO-LAR)protocol for *** EAMO-LAR protocol makes use of manta ray foraging optimization algorithm(MRFO)to help the searching process for the individual solution to be passed to the LAR *** fitness value of the created solutions is determined next to pass the solutions to the objective *** MRFO algorithm is incorporated into the LAR protocol in the EAMO-LAR protocol to reduce the desired energy *** ensure the improved routing efficiency of the proposed EAMO-LAR protocol,a series of simulations take *** resultant experimental values pointed out the supreme outcome of the EAMO-LAR protocol over the recently compared *** resultant values demonstrated that the EAMO-LAR protocol has accomplished effectual results over the other existing techniques.

关键词： MANET routing lar protocol energy efficiency mrfo algorithm metaheuristics