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Rare Metals 2006年第z2期25卷 179-183页

作者： PARK Jong Suk lee kyung Tae lee kyung Sub Department of Material Science and Engineering Hanyang University Seoul 133-731 Korea

In order to control the size and distribution of the high conductive Fe2P in LiFePO4/Fe2P composite, two different cooling rates (Fast: 15 ℃·min-1, Slow: 2 ℃·min-1) were employed after mechanical alloying. The discharge capacity of the fast cooled was 83 mAh·g-1 and the slow cooled 121 mAh·g-1. The particle size of the synthesized powder was examined by transmission electron microscopy and distribution of Fe2P was characterized using scanning electron microscopy (SEM). In addition, two-step heat treatment was carried out for better distribution of Fe2P. X-ray diffraction (XRD) and Rietveld refinement reveal that LiFePO4/Fe2P composite consists of 95.77% LiFePO4 and 4.33% of Fe2P.

关键词： LiFePO4/Fe2P composite mechanical alloying heat treatment discharge capacity

Densification simulation of compacted Al powders using multi-particle finite element method

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中国有色金属学会会刊：英文版 2009年第B09期19卷 68-75页

作者： kyung-Hun lee Jung-Min lee Byung-Min KIM School of Mechanical Engineering Pu san National University

The powder compaction simulations were performed to demonstrate deformation behavior of particles and estimate the effect of different punch speeds and particle diameters on the relative density of powder by a multi-particle finite element model(MPFEM). Individual particle discretized with a finite element mesh allows for a full description of the contact mechanics. In order to verify the reliability of compaction simulation by MPFEM, the compaction tests of porous aluminum with average particle size of 20 μm and 3 μm were performed at different ram speeds of 5, 15, 30 and 60 mm/min by MTS servo-hydraulic tester. The results show that the slow ram speed is of great advantage for powder densification in low compaction force due to sufficient particle rearrangement and compaction force increases with decrease in average particle size of aluminum.

关键词：粉末压实粉末粒子多孔铝有限元法模拟致密化平均粒径有限元模型

A Miniaturized Tadpole Robot Using an Electromagnetic Oscillatory Actuator

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Journal of Bionic Engineering 2015年第1期12卷 29-36页

作者： Bu Hyun Shin kyung-Min lee Seung-Yop lee Department of Mechanical Engineering Hanbat National University Daejeon 305-719 Korea Convergence Technology Examination Division Korean Intellectual Property Office Daejeon 302-701 Korea Department of Mechanical Engineering Sogang University Seoul 121-742 Korea

In this paper, we propose a miniaturized tadpole-like robot using an electromagnetic oscillatory actuator. The electro- magnetic actuator has a simple structure with a moving-magnet type and the body size is 13 mm （length） × 11 mm （height） ×10 mm （width）. A tail has the thickness of 100 μm and the length of 20 mm which is twice of the body-length （BL）. The tail attached to the oscillatory actuator generates undulatory propulsion for the forward swimming. Moreover, the tadpole robot enables the change of the direction by controlling input signal pattems applied to the oscillatory actuator. Prototypes of the tadpole robot have been manufactured and the thrust force and swimming speed are measured to evaluate the performance of the biomimetic robot in water at various tail-beat frequencies. The maximum thrust force is 42 mN at the tail-beat frequency of 30 Hz with voltage of 3 V, enabling the tadpole robot to swim at the speed of 210 mm·s^-1 （6 BL·s^-1）. The tadpole robot can also change its moving direction with the angular velocity of 21 deg·s^-1 at the half pulse pattem of 30 Hz.

关键词： fish robot biomimetics tadpole robot electromagnetic actuator

Effects of elastic-plastic properties of materials on residual indentation impressions in nano-indentation using sharp indenter

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中国有色金属学会会刊：英文版 2012年第S3期22卷 585-595页

作者： Jung-Min lee Chan-Joo lee kyung-Hun lee Byung-Min KIM Dongnam Regional Division Korea Institute of Industrial Technology Precision Manufacturing Systems Division Pusan National University School of Mechanical Engineering Pusan National University

One of the primary features of nano-indentation technique is that the contact area induced by an indenter is indirectly measured by a relationship between the penetration depth and the known geometry of the ***,this indirect measurement occasionally leads to inaccurate properties of the indented *** objective of this study is to investigate the effects of E/σr and the strain hardening exponents n of materials on the behaviors of pile-up and sink-in in nano-indentation and to predict n values of materials from the residual indentation *** relations between the residual indentation profile and n value of the indented material were identified by dimensional ***,they were numerically formulated using FE analysis of nano-indentation for 140 different combinations of elastic-plastic parameters such as E,σy and *** parameters of hrp/hm,herp/hm,Rr/hm and HO&P/Hreal were introduced as various dimensionless parameters to represent and quantify the residual indentation profile after *** were subsequently characterized as dimensionless functions using n and E/σr ***,the validity of these functions was verified through 3D FE analysis of nano-indentation for Al 6061-T6 and AISI 1010 materials.

关键词： nano-indentation pile-up sink-in strain hardening exponent FE simulation

PASSIVE DESIGN TECHNIQUES APPLIED TO GREEN BUILDINGS AS AN AESTHETIC AND SPATIAL DESIGN CONCEPT

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Journal of Green Building 2015年第2期10卷 79-109页

作者： Jiyoung lee kyung Sun lee Jaehan Lim Department of Architecture Cheongju University 586Daesung-roNaedok dongSangdang guCheongjuChungbuk360-764Korea School of Architecture Hongik UniversityMH140894 Wausan-roMapo-guSeoul121-791Korea Department of Architectural Engineering Ewha Womans University52 Ewhayodae-gilSodaemun-guSeoul120-750Korea

*** The emergence of environmental problems as major social issues throughout the world has prompted sustainable development efforts in a wide range of areas,including industry,construction,and transportation,followed by the execution of numerous studies and *** concept of sustainable development has been dealt with in earnest in the construction field since the Declaration of Interdependence for a Sustainable Future at the 18th Chicago Convention of UIA in *** Declaration included tasks to be implemented with respect to green buildings,such as the recycling of resources,application of energy-efficient designs,and utilization of natural energy in addition to the application of sustainable *** part of green building practices,countries around the world have been implementing various green building certification standards,such as leeD,GBCC,CASBEE,and BREEAM.

关键词： Sustainability Energy Conservation Passive Design Building Use Climate Zones

Sequential disruption of ALV host receptor genes reveals no sharing of receptors between ALV subgroups A, B, and J

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Journal of Animal Science and Biotechnology 2019年第2期10卷 410-423页

作者： Hong Jo lee kyung Je Park kyung Youn lee Yongxiu Yao Venugopal Nair Jae Yong Han Sciences and Research Institute of Agriculture and Life SciencesSeoul National UniversitySeoul 08826Korea The Pirbright Institute WokingSurrey GU24 0NFUK.

Background: Previously, we showed that targeted disruption of viral receptor genes in avian leukosis virus(ALV)subgroups using clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9))-based genome editing confers resistance to ALV subgroups B and J. Here, we used the same strategy to target the receptor expressed by ALV subgroup A(TVA) and generate chicken cells resistant to infection by this ***: CRISPR/Cas9-based disruption of exon 2 within the tva gene of DF-1 fibroblasts conferred resistance to infection by ALV subgroup A regardless of whether frameshift mutations were introduced during editing. Conversely,overexpression of the wild-type TVA receptor(wtTVA) by tva-modified DF-1 clones restored susceptibility to ALV subgroup A. The results confirm that exon 2, which contains the low-density lipoprotein receptor class A domain of TVA, is critical for virus entry. Furthermore, we sequentially modified DF-1 cells by editing the tva, tvb, and Na^+/H^+ exchange 1(chNHE1) genes, which are the specific receptors for ALV subgroups A, B, and J, ***: Simultaneous editing of multiple receptors to block infection by different subgroups of ALV confirmed that ALV subgroups A, B, and J do not share host receptors. This strategy could be used to generate cells resistant to multiple viral pathogens that use distinct receptors for cell entry.

关键词： Avian leukosis virus CRISPR/Cas9 Genome editing Host receptor TVA

FEA technique of hot plate forming process using cell-typed die with cooling device

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中国有色金属学会会刊：英文版 2012年第S3期22卷 831-837页

作者： Jung-Min lee In-Kyu lee kyung-Hun lee Dae-Soon KIM Byung-Min KIM Dongnam Regional Division Korea Institute of Industrial Technology School of Mechanical Engineering Pusan National University Industrial Technology Division Hyundai Heavy Industries

Hot plate forming using a cell-typed die is a process for forming a large thick plate with a spherical shape for the manufacture of a large spherical LNG ***-typed upper and lower dies made of a framework of steel plates fitted to make a grid pattern are used in this process,and an air-cooling device is separately installed inside the lower die.A finite element analysis (FEA) technique was developed,which included hot forming,air flow,cooling and thermal deformation analysis for the hot plate forming process using the cell-typed ***,the convective and interface heat transfer coefficients were used to reproduce analytically the effects of the cooling device in the hot plate forming analysis.A small-scale model test of the process was conducted to verify the FEA *** analysis results show that the curvature of the final plate agrees well with that of the designed experiment within a maximum relative error of 0.03% at the corner of the plate.

关键词： cell-typed die hot plate forming spherical LNG tank heat transfer coefficient

Miniaturized Twin-legged Robot with an Electromagnetic Oscillatory Actuator

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Journal of Bionic Engineering 2018年第1期15卷 106-113页

作者： Buhyun Shin Youngshik Kim Jamie Paik kyung-min lee Department of Mechanical Engineering Hanbat National University 125 Dongseodaero Yuseong-gu Daejeon 34158 Republic of Korea The Institute of Mechanical Engineering EPFL BM 4118 Station 17 1015-Lausanne Switzerland School of Mechanical Engineering Yeungnam University 280 Daehak-Ro Gyeongsan Gyeongbuk 38541 Republic of Korea

There have been many studies on the moving mechanism of micro robots, such as stick-slip, inchworm like motion, and impact drive. Novel actuators like lead zirconate titanate （PZT）, Shape Memory Alloy （SMA）, magnetostrictive materials, electromagnetic actuators, electoractive polymers, ultrasonic linear motors, and dielectric elastomers are utilized to realize the moving mechanism. The use of a conventional electromagnetic actuator is unfavorable, because of a few drawbacks, such as generation of stray magnetic fields, hard to miniaturize to the millimeter scale because of 3D integration and a scaling law, and power consumption to maintain a certain position. This research presents a micro robot that uses an electromagnetic actuator customized and developed for micro robot. The electromagnetic actuator is designed from a Brushless Direct Current （BLDC） motor to overcome the drawbacks mentioned above. The developed robot is composed of two electromagnetic actuators. The overall size of the robot is 20 mm × 11 mm× 9 mm （length × height × width） and the weight is 3 g. The developed robot is able to move bidirectionally with a maximum moving speed of 15.76 mm·s︿-1 （0.79 body-length per second）. The optimal conditions of an input signal are calculated theoretically and verified with experiments.

关键词： electromagnetic actuator oscillatory actuator bionic micro robot stick-slip brushless DC motor

Ethnic differences in gastric cancer genetic susceptibility:Allele flips of interleukin gene

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World Journal of Gastroenterology 2014年第16期20卷 4558-4565页

作者： Juwon Kim Yoonjung Kim kyung-a lee Department of Laboratory Medicine Yonsei University Wonju College of MedicineGangwon-do 220-701South Korea Department of Laboratory Medicine Yonsei University College of MedicineSeoul 135-720South Korea

Polymorphisms in promoter regions of inflammatory cytokines have been widely studied,and potentially functional polymorphisms have been *** results from meta-analyses of interleukin(IL)-1B and IL-10 polymorphisms show differences in gastric cancer susceptibilities between Caucasian and Asian *** particular,we note the suggestion of an allele flip in IL-1B and IL-10 gene *** Asian populations,the IL-1B-1464G/-511C/-31T haplotype indicates risk for gastric cancer,while the opposite haplotype,IL-1B-1464C/-511T/-31C is the risk-related allele in ***,while IL-10-1082G/-819C/-592C is associated with gastric cancer in Asians,IL-10-1082A/-819T/-592T is linked to gastric cancer risk in *** seemingly contradictory results may be attributed to distinct carcinogenic mechanisms underlying the different gastric cancer *** allele flip observed in IL-10 and gastric cancer appears to reflect allelic heterogeneity,similar to that observed in *** this review,we focus on the allele flip phenomenon observed between different ethnic groups in an effort to resolve certain controversial results from recent studies on interleukin *** addition,we re-emphasize the importance of stratifying gastric cancer subtypes based on anatomical site and Lauren classification to prevent false associations arising through dilution of true ones.

关键词： Allele flip Gastric cancer Interleukin gene

Clawed Miniature Inchworm Robot Driven by Electromagnetic Oscillatory Actuator

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Journal of Bionic Engineering 2015年第4期12卷 519-526页

作者： kyung-min lee Youngshik Kim Jamie K. Paik Buhyun Shin Korean Intellectual Property Office Gov. Complex-Daejeon Bldg. 4 189 Cheongsa-ro Se-gu Daejeon 302-701 Korea Department of Mechanical Engineering Hanbat National University 125 Dongseodaero Yuseong-gu Daejeon 305-719 Korea The Institute of Mechanical Engineering EPFL STIlGM UPPAIK BM 4118 (B~timent BM) Station 17 Switzerland

In this research we propose a novel inchworm robot, which is composed of an Electromagnetic Oscillatory Actuator （EOA） and claws. The EOA consists of a yoke, a magnet, and a coil. The overall robot size is 12.2 mm x 11 mm x 9 mm （length x height ~ width）. The locomotion of the robot is achieved by different amounts of slips when the robot stretches and contracts its front leg. To realize locomotion, the working conditions were calculated theoretically and the calculated input signal was applied to the robot. The performance of the inchworm robot was evaluated experimentally with varying input voltages and frequencies. A simple op-amps based driving circuit was used to provide a square-wave input. Travel speed, average distance per step of the robot, and moving distance of the leg and body at each step were measured. The maximum travel speed was 36 mm-s-1 at 30 Hz, which validates our simple locomotion strategy experimentally.

关键词： electromagnetic actuator micro mobile robot inchworm crawler locomotion