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基于双能CT深度学习预测取栓术后的脑出血转化

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国际医学放射学杂志 2024年第4期 502-502页

作者： J.Heo y.yoon H.J.Han J.J.kim K.y.Park B.M.kim 常嫣格

摘要目的利用双能CT开发和验证一个深度学习模型，预测血管内取栓术后的脑出血转化。方法该项基于急性缺血性卒中前瞻性登记的回顾性研究，纳入2019年5月—

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Variations in microstructure and bending formability of extruded Mg–Al–Zn–Ca–y–MM alloy with precompression and subsequent annealing treatment conditions

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Journal of Magnesium and Alloys 2022年第9期10卷 2475-2490页

作者： Jong Un Lee Sang-Hoon kim Dong Hee Lee Hyun Ji kim young Min kim Sung Hyuk Park School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Agency for Defense Development Daejeon 34186Republic of Korea Implementation Research Division Korea Institute of Materials ScienceChangwon 51508Republic of Korea

In this study, the bending formability of an extruded Mg–9Al–1Zn–0.3Mn–0.9Ca–0.6y–0.5 MM(AZXWMM91100, wt%) alloy at room temperature is significantly improved through application of a combined precompression and subsequent annealing(PCA) treatment. As the amount of precompression applied along the extrusion direction(ED)(i.e., the total strain) increases from 4% to 6%, the area fraction of ED-oriented grains of the PCA-treated alloy increases, which consequently causes an improvement in its bending formability because these grains accommodate larger tensile strain along the ED during bending. As the temperature of the subsequent annealing treatment increases from 350 ℃ to 450 ℃, both the area fraction of the ED-oriented grains and the average grain size increase, and the residual dislocation density decreases owing to the promotion of boundary migration and occurrence of the recovery process at higher ***, the bending formability of both the 4%-precompressed and the 6%-precompressed samples increases with an increase in the annealing temperature. However, when the precompressed samples are annealed at 300 ℃, their bending formability is lower than that of the extruded alloy because the dislocations formed by precompression remain even after the subsequent annealing at this temperature.

关键词： Magnesium Extrusion Bending Formability Texture

Molecular Dynamics Simulation for Grain Boundary Deformation under Tensile Loading Condition

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Journal of Materials Science & Technology 2001年第1期17卷 145-146页

作者： kim y.S. Choi D.y. Won S.y. Dep. of Mech. Eng. Kyungpook Natl. Univ. Kyungpook South Korea

MD (molecular dynamics) simulations have been performed to observe the behavior of a grain boundary in the α-Fe plate under 2-dimensional loading. In MD simulation, the acceleration of every molecule can be achieved from the potential energy and the force interaction between this molecule and other molecules , and the integration of the motion equation by using Verlet method gives the displacement of each molecule. Initially, four α-Fe rectangular plates having different misorientation angles of the grain boundary are modeled by using the Johnson potential and the Morse potential. The potential energy of the grain boundary system is compared with that of the perfect structure model. Also, the width of the grain boundary can be obtained by investigating the local potential energy distribution. The tensile loading for each grain boundary model is applied and the behavior of the grain boundary is studied. From this study it is clarified that in the case of using the Johnson potential, the obvious fracture mechanism occurs along the grain boundary, and in the case of using the Morse potential, the diffusion of the grain boundary appears instead of the grain boundary fracture.

关键词： Simulation Molecular Dynamics Simulation for Grain Boundary Deformation under Tensile Loading Condition

Rice pollen-specific OsRALF17 and OsRALF19 are essential for pollen tube growth

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植物学报:英文版 2023年第9期65卷 2218-2236页

作者： Eui‐Jung kim Ji‐Hyun kim Woo‐Jong Hong Eun young kim Myung‐Hee kim Su Kyoung Lee Cheol Woo Min Sun Tae kim Soon Ki Park Ki‐Hong Jung yu‐Jin kim Graduate School of Green Bio‐Science&Crop Biotech Institute Kyung Hee UniversityYongin 17104Republic of Korea Department of Life Science and Environmental Biochemistry Life and Industry Convergence Research InstitutePusan National UniversityMiryang 50463Republic of Korea Department of Smart Farm Science Kyung Hee UniversityYongin 17104Republic of Korea School of Applied Biosciences Kyungpook National UniversityDaegu 41566Republic of Korea Genomics Division Department of Agricultural Bio‐ResourcesNational Institute of Agricultural SciencesRural Development AdministrationJeonju 54874Republic of Korea Department of Plant Bioscience Pusan National UniversityMiryang 50463Republic of Korea Research Center for Plant Plasticity Seoul National UniversitySeoul 08826Republic of Korea

Pollen tube growth is essential for successful double fertilization, which is critical for grain yield in crop plants. Rapid alkalinization factors(RALFs) function as ligands for signal transduction during fertilization. However, functional studies on RALF in monocot plants are ***, we functionally characterized two pollen-specific RALFs in rice(Oryza sativa) using multiple clustered regularly interspaced palindromic repeats(CRISPR)/CRISPR-associated protein 9-induced loss-of-function mutants,peptide treatment, expression analyses, and tag reporter lines. Among the 41 RALF members in rice, OsRALF17 was specifically expressed at the highest level in pollen and pollen *** applied OsRALF17 or OsRALF19peptide inhibited pollen tube germination and elongation at high concentrations but enhanced tube elongation at low concentrations, indicating growth regulation. Double mutants of OsRALF17 and OsRALF19(ralf17/19) exhibited almost full male sterility with defects in pollen hydration, germination, and tube elongation,which was partially recovered by exogenous treatment with OsRALF17 peptide. This study revealed that two partially functionally redundant OsRALF17 and OsRALF19 bind to Oryza sativa male-gene transfer defective 2(OsMTD2) and transmit reactive oxygen species signals for pollen tube germination and integrity maintenance in rice. Transcriptomic analysis confirmed their common downstream genes, in osmtd2 and ralf17/19. This study provides new insights into the role of RALF, expanding our knowledge of the biological role of RALF in regulating rice fertilization.

关键词： CRISPR-Cas9 CrRLK1L monocot Oryza sativa pollen tube growth rapid alkalinization factor(RALF)

Effects of Mo and Zr on Microstructure,Mechanical Properties and Wear Resistance of Fe-Al Based Alloys

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Journal of Materials Science & Technology 2008年第3期24卷 309-312页

作者： I.D.yeo H.S.kim y.G.yoo W.y.kim Advanced Materials R&D Division Korea Institute of Industrial Technology7-47Songdo-dongYeonsu-gu

In this work the microstructure, mechanical properties and wear resistance of Fe-Al based alloys with various alloying elements were studied. The microstructures were examined by optical and scanning electron microscopy （SEM） equipped with an energy dispersive X-ray spectroscope （EDS）. Two types of alloys were prepared by vacuum arc melting. One is Fe-28Al based alloys （D03 structured） with and without alloying elements such as Mo and Zr. The other one is Fe-35Al based alloys （B2 structured） produced with the same manner. For both types of alloys, Mo addition had found to exhibit an equiaxed microstructure, while dendritic structure was observed to show the effect of Zr addition. These microstructural features were more evinced with increasing content of alloying element. Concerning the mechanical properties and wear resistance, Fe-35Al based alloys were superior to Fe-28Al based alloys over the whole temperature range investigated.

关键词： Fe-Al alloy Intermetallic Mechanical properties Wear resistance

High Temperature Mechanical Properties of Ni-Al-Cr Based Alloys for Advanced Die-Materials Applications

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Journal of Materials Science & Technology 2008年第3期24卷 305-308页

作者： W.y.kim H.S.kim y.G.yoo I.D.yeo Advanced Materials R&D Division Korea Institute of Industrial Technology7-47Songdo-dongYeonsu-gu

In this study, we report on advanced Ni3Al based high temperature structural alloys with Zr and B addition in order to apply in the fields of die-casting and high temperature press forming as die materials. Microstructures and mechanical properties of Ni3Al based intermetallic alloys produced by vacuum arc melting were investigated in terms of phase analysis by using a scanning electron microscope （SEM） equipped with an X-ray energy dispersive spectrometer （EDS）, an X-ray diffractometer （XRD） and tensile test. The duplex microstructural feature consisting of γ＇ matrix phase and small intermetallic dispersoids was observed to be distributed over the whole microstructure. The ultimate tensile strength of the present alloy was superior to commercial iron-based and Ni-based die-materials especially in the high temperature region.

关键词： Intermetallic Die material Alloying effect Mechanical property

MOLECULAR DESIGN OF LIGHT EMITTING POLyMERS

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Chinese Journal of Polymer Science 2000年第3期18卷 227-237页

作者： J.W.yu J.K.kim J.MHong y.C.kim H.N.Cho D.y.kim C.y.kim Polymer Materials Laboratory Korea Institute of Science and Technology P.O. Box 131 Cheongryang Seoul 130-650. KoreaPolymer Materials Laboratory Korea Institute of Science and Technology P.O. Box 131 Cheongryang Seoul 130-650. KoreaPolymer Materials Laboratory Korea Institute of Science and Technology P.O. Box 131 Cheongryang Seoul 130-650. KoreaPolymer Materials Laboratory Korea Institute of Science and Technology P.O. Box 131 Cheongryang Seoul 130-650. KoreaPolymer Materials Laboratory Korea Institute of Science and Technology P.O. Box 131 Cheongryang Seoul 130-650. KoreaPolymer Materials Laboratory Korea Institute of Science and Technology P.O. Box 131 Cheongryang Seoul 130-650. KoreaPolymer Materials Laboratory Korea Institute of Science and Technology P.O. Box 131 Cheongryang Seoul 130-650. Korea

Fluorene-based alternating and statistical copolymers were synthesized by employing reaction methods of Wittig,Heck and Suzuki. The copolymers were classified into three groups with the photoluminescence (PL) emission maxima at420, 475 and 500 nm, respectively. Statistical copolymers with two chromophores having PL emission maxima at 420 and475 nm emitted light with the emission maximum at 475 nm on photoexcitation at 365 nm and improved the quantumefficiency by the energy transfer. However, the intramolecular energy transfer was inefficient compared to the intermolecularenergy transfer when the two chromophores were apart from each other in the range of the Forster critical distance. Fluorene-pyridinedivinylene alternating copolymer was synthesized by the Wittig reaction and found to have physical, electronic andelectrochemical properties of the individual units intact. The double-layered light emitting diode (LED) with the statisticalcopolymer as an emitting layer and the pyridine-containing copolymer as an electron transporting-hole blocking layer, whichwere sandwiched between ITO and Al, displayed a quantum efficiency of 0.1%.

关键词： Light emitting polymers

CO_2 laser-micro plasma arc hybrid welding for galvanized steel sheets

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Transactions of Nonferrous Metals Society of China 2011年第A1期21卷 47-53页

作者： C.H.kim y.N.AHN J.H.kim Advance Welding & Joining Research Group Korea Institute of Industrial Technology Incheon 406-840 South Korea

A laser lap welding process for zinc-coated steel has a well-known unsolved problem-porosity formation. The boiling temperature of coated zinc is lower than the melting temperature of the base metal, which is steel. In the autogenous laser welding, the zinc vapor generates from the lapped surfaces expels the molten pool and the expulsion causes numerous weld defects, such as spatters and blow holes on the weld surface and porosity inside the welds. The laser-arc hybrid welding was suggested as an alternative method for the laser lap welding because the arc can preheat or post-heat the weldment according to the arrangement of the laser beam and the arc. CO2 laser-micro plasma hybrid welding was applied to the lap welding of zinc-coated steel with zero-gap. The relationships among the weld quality and process parameters of the laser-arc arrangement, and the laser-arc interspacing distance and arc current were investigated using a full-factorial experimental design. The effect of laser-arc arrangement is dominant because the leading plasma arc partially melts the upper steel sheets and vaporizes or oxidizes the coated zinc on the lapped surfaces. Compared with the result from the laser-TIG hybrid welding, the heat input from arc can be reduced by 40%.

关键词： CO2激光镀锌钢板复合焊接等离子弧电弧电流焊缝表面微等离子体焊接热输入

Optimization Analysis of Sustainable Solar Power System for Mobile Communication Systems

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Computers, Materials & Continua 2022年第5期71卷 3243-3255页

作者： Mohammed H.Alsharif Raju Kannadasan Amir y.Hassan Wael Z.Tawfik Mun-Kyeom kim Muhammad Asghar Khan Ahmad A.A.Solyman Department of Electrical Engineering College of Electronics and Information EngineeringSejong University209 Neungdong-roGwangjin-guSeoul05006Korea Department of Electrical and Electronics Engineering Sri Venkateswara College of EngineeringSriprumbudurChennai602117India Department of Power Electronics and Energy Conversion Electronics Research InstituteGiza12622Egypt Department of Physics Faculty of ScienceBeni-Suef UniversityBeni-Suef62511Egypt Department of Energy System Engineering Chung-Ang University84 Heukseok-roDongjak-guSeoul156-756Korea Department of Electrical Engineering Hamdard University Islamabad44000Pakistan Department of Electrical and Electronics Engineering Istanbul Gelisim UniversityAvcılar34310Turkey

Cellular mobile technology has witnessed tremendous growth in recent *** of the challenges facing the operators to extend the coverage of the networks to meet the rising demand for cellular mobile services is the power sources used to supply cellular towers with energy,especially in ***,switch from the conventional sources of energy to a greener and sustainable power model became a target of the academic and industrial sectors in many fields;one of these important fields is the telecommunication ***,this study aims to find the optimum sizing and technoeconomic investigation of a solar photovoltaic scheme to deploy cellular mobile technology infrastructure cleanly and *** optimal solarpowered system is designed by employing the energy-balance procedures of the HOMER software *** problem objective is considered in terms of cost,but the energy system is constrained to meet the power demand *** simulations were performed to determine the optimum sizing,performance and monetary cost of the power system,using long-term meteorological datasets for a case study site with defined longitude(31◦25E)and latitude(30◦06N).From the observed results,the total net present cost(NPC)of the proposed system is$28,***,these outcomes can provide profound economic,technical,and ecological benefits to cellular *** also ensures a sizeable reduction in greenhouse gas that supports sustainable green wireless network(WN)deployment in remote areas.

关键词： Wireless networks green wireless networks green communications sustainability OPEX