Evaluation of Hot Deformation and Dynamic Recrystallization Behaviors of Advanced Reduced-Activated Alloy (ARAA)

Sang‑Wook Kim,Hyeon‑Woo Son,Taek‑Kyun Jung,Young‑Bum Chun,Yi‑Hyun Park,Ji‑Woon Lee,Soong‑Keun Hyun 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.4

The hot deformation behavior of advanced reduced-activation alloy (ARAA) was investigated using hot torsion tests. Thefl ow stress decreased as deformation temperature increased and as strain rate decreased. The fl ow behavior demonstratedthe typical dynamic recrystallization (DRX). Based on the constitutive analysis of peak stress, the activation energy for hotdeformation was found to be 330.3 kJ mol −1 . Peak stress was analyzed as a function of the Zener–Hollomon parameter, andcalculated and experimental values were in good agreement. A DRX kinetic model for ARAA was derived with deformationconditions based on the Avrami-type model. It was confi rmed that the volume fraction of dynamically recrystallized grainsincreased as deformation temperature increased and as strain rate decreased. The necklace structure and grain boundarybulging were observed in the deformed microstructure of ARAA. The suggested DRX mechanism for ARAA during hotworking is discontinuous DRX.

Effects of Pilger Rolling and Heat Treatment on Microstructure and Corrosion Resistance of Ag-electroplated 304 Stainless Steel Tubes

Hyun Park,Woo‑Jin Lee,Jae‑Han Son,Han‑Kyun Shin,Sung‑Kyu Hong,Hyo‑Jong Lee 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.8

We introduce a cost-effective method that combines electroplating with metal cold working processes to manufacture compositetubes with robust corrosion resistance. First, a 3-step electroplating process was developed to form an adhesive anduniform Ag coating on the outer wall of a 304 stainless steel tube. The process consisted of a Ni-strike step for removing thepassivation layer of the initial 304 tube, Cu deposition for smoothing the surface by adding a buffer layer, and Ag deposition. To reinforce the interfacial adhesion between the electroplated layers and the 304 tube and increase the area of the Ag coating,a pilger rolling or pilger rolling + heat-treatment process was performed after the Ag electroplating process. Scanningelectron microscopy of the composite tubes after each process indicated that the as-deposited Ag coating changed fromhaving a rough to smooth surface after only pilger rolling and with additional heat treatment. Electron backscatter diffractionanalysis of the microstructures and textures of the tubes revealed that dynamic recrystallization occurred extensively duringpilger rolling, resulting in the formation of a relatively defect-free grain structure without heat treatment. Furthermore,electrochemical polarization curves determined that the Ag-coated composite tubes are superior to the uncoated 304 tubein terms of corrosion resistance under Cl−atmosphere, owing to the formation of a AgCl passivation layer during testing. Surface analysis of the composite tubes suggests that the properties of the AgCl passivation layer are related to the grainsize of the Ag coating and the density of plastic-deformation-induced defects.

Request and Question Perspective in Interlanguage Pragmatics

Sung Kyu Yun,Woo-hyun Jung 한국사회언어학회 2004 사회언어학 Vol.12 No.2

Yun, Sung Kyu & Jung, Woo-hyun. 2004. Request and Question Perspective in Interlanguage Pragmatics. The Sociolinguistic Journal of Korea, 12(2). This paper is an interlanguage pragmatic study of request and question perspective. It aims to explore whether there are any differences in request perspective between American English native speakers and Korean EFL learners. To this end, this study employed a Discourse Completion Test, which consisted of eight situations. Data were collected from three different groups: native speakers of English; Korean learners of English; native speakers of Korean. The results showed that the learners deviated from native pragmatic norms in the choice of perspective in a relatively systematic way. The same held even more obviously in the use of please in interacting with request perspective. It was also shown that the mismatch between the native and nonnative groups in perspective was an instance of pragmatic transfer. The results suggested that the notions of imposition and politeness operated differently in perspective between the native and nonnative groups. It is expected that this study will shed light on the phenomenon of interlanguage pragmatics and the aspect of pragmatic transfer, revealing how learners differ from native speakers with respect to request perspective and what causes the differences.

행우서옥본(杏雨書屋本)『황제내경태소(黃帝內經太素)』 권(卷)21, 권(卷)27의 출간(出刊) 의의(意義)와 그 내용에 대한 고찰(考察)

김종현 ( Jong Hyun Kim ),백유상 ( You Sang Baik ),장우창 ( Woo Chang Jang ),정창현 ( Chang Hyun Jeong ) 대한한의학원전학회(구 대한원전의사학회) 2011 대한한의학원전학회지 Vol.24 No.5

『Hwangjenaegyeong-taeso(黃帝內經太素)』 is a classic work of Yang Sang-seon(楊上善), which comprises original articles of 『Hwangjenaegyeong(黃帝內經)』 along with 『Somun(素問)』, 『Yeongchu (靈樞)』, and 『gapeul(甲乙)』, as a one of the oldest annotated publications. Therefore, its significance lies in that 『Hwangjenaegyeong-taeso(黃帝內經太素)』 is a valuable work to reconstruct the original text of 『Hwangjenaegyeong(黃帝內經)』 and comprehend its fundamental ideas. The only printed edition of 『Hwangjenaegyeong-taeso(黃帝內經太素)』 was photocopied in 1981, and is currently known as ``Orient Edition``. While ``Orient Edition`` was referred to as the draft for the latest revised edition, volume 21 and 27 were photocopied from hand-copied edition, not the original. The original publications of ``Orient Edition`` have been stocked at ``Haengwuseook(杏雨書屋)`` of Japan and were recently published. Hence, a comparative study between the two original volumes and the former ones has been conducted. Although the most of the differences were trivial, some may have led to distorted interpretation of the text. The errors of the former revised edition fall into a few specific categories, and the most significant ones were errors that were made during the hand-copying procedure. Moreover, there were errors that were made due to the low resolution of the former draft, and simple errors during the publishing. In this work, examples of such cases were presented, and the results were collected.

국내 한의학 학술지에 발표된 동의보감 연구 현황 조사

한창현(Chang-hyun Han),박상영(Sang-young Park),권오민(Oh-min Kwon),안상영(Sang-young Ahn),안상우(Sang-woo Ahn) 한국의사학회 2009 한국의사학회지 Vol.22 No.2

Background : To understand Korean medicine it is crucial to first understand medical aspect of ‘DongUiBoGam’. It is also meaningful that it became one of the influential book even to posterity. Also based on the apprehension, we can take a view of development of Korean medicine led by ‘DongUiBoGam’. Objectives : This study aims to review the status, study field, specialist of DongUiBoGam. In the process, this review will grasp trends in this field of studies and will direct further researches into the right direction. Method : The computerized Korean databases were searched from their respective inceptions up to December 2008. The search terms used were ‘DongUiBoGam’ and random or Korean language terms related to DongUiBoGam. Several specialized journals were also manually searched for relevant articles. Result : Since the 2000s, DongUiBoGam papers in the Korean Literature is increased. Published 58 papers on The Korean Journal of Oriental Medical Prescription were more than the other journals. 58 papers published in The Korean Journal of Oriental Medical Prescription are the best in many areas related to Korean medicine. Most people have submitted papers related to DongUiBoGam was Woo-yeal Jeong. Conclusions : ‘DongUiBoGam’ research is conducted and current tendency and outlook for ‘DongUiBoGam’ is carried out focusing on several associations.

기관지폐 이형성증의 임상 양상: 다기관 연구

성기혜 ( Ki Hye Sung ),김민희 ( Min Hee Kim ),김은령 ( Eun Ryoung Kim ),심재원 ( Jae Won Shim ),이정주 ( Jung Ju Lee ),임재우 ( Jae Woo Im ),진현승 ( Hyun Seung Jin ) 대한주산의학회 2009 Perinatology Vol.20 No.3

목적: 최근 극소 저출생 체중아의 생존율의 개선으로 기관지폐 이형성증(bronchopulmonary dysplasia, BPD)이 늘고 있다. 다기관 연구에 의해 전국적인 BPD의 역학, 임상 양상과 각 병원 간의 차이를 조사하여 향후 우리나라의 BPD 감소와 중증도를 줄이는 것을 목적으로 본 연구를 시행하였다. 방법: 2005년 6월부터 2007년 5월까지 건국대학교병원, 영등포 성애병원, 강북삼성병원, 중앙대학교병원, 건양대학교병원, 강릉아산병원의 신생아 집중 치료실에 입원하였던 신생아 4,476명을 대상으로 하였다. BPD의 진단 기준은 비전형적인 BPD를 포함하여 병인적인 분류를 하고 있는 Ogawa 등의 분류법을 이용하여 신생아 호흡 곤란 증후군(respiratory distress syndrome, RDS)과 전형적 또는 미만성 혼탁의 방사선 소견, 산전 감염의 유무에 따라 6가지 type으로 분류하였다. 또한 전체 신생아의 출생체중 분포와 생존율, 각 출생체중 군별 BPD의 발생률, 병태 비율, 사망률 등을 조사하고, 이 후 재택 산소요법 시행 여부와 미숙아 망막증, 괴사성 장염 등의 합병증 여부를 조사하였다. 결과: 생후 28일째 산소 치료가 필요한 신생아는 89명이었고, 이 중 Ogawa 분류법에 의한 BPD 환아는 70명(1.6%)이었으며, 특히 1,500 g 미만의 환아 237명 중 60명(25.3%)이었다. 생후 28일 이상 생존율은 98.7%이고, 사망 예는 없었으며 평균 재원 기간은 97.8±51.2일(43~405일)이었다. BPD는 900~999 g, 1,000~1,249 g의 체중 군에서 발생률이 각각 15명(21.4%)으로 가장 높았으며, 교정 36주 이후에도 산소투여가 필요한 중증 BPD의 경우 900~999 g의 체중 군에서 7명(23.3%)로 가장 높았다. Ogawa 분류법으로 BPD의 각 병태 비율로는 RDS 이후에 나타나는 I, II형이 각각 전체의 17예(24.3%), 44예(62.9%)로 대다수를 차지하였다. 이외에도 III`형은 2예(2.9%), IV형은 2예(2.9%), V형은 5예(7.1%)이었고, III형, VI형은 없었다. 재택 산소요법은 8예에서 시행되어 전체의 11.4%였으며, 이 중 BPD I형이 7예로 87.5%를 차지하였다. 미숙아 망막증은 35명(50.0%)에서 발생하였으며, 700 g 이하 신생아에서 9예(26.5%)로 가장 많았다. 또한 괴사성 장염은 3명(4.3%)이었다. 결론: 본 연구는 국내에서 처음으로 진행된 BPD의 전국적인 다기관 역학 조사로, 대상 신생아의 Ogawa 분류에 의한 BPD 유병률은 1.6% 이었고 1,500 g 미만 신생아의 25.3%이었으며, 전체 신생아의 BPD 70명 중 Ogawa 분류의 I, II형이 각각 24.3%, 62.9%로 대다수를 차지하였다. Purpose: As the neonatal intensive care advanced, the incidence of neonatal bronchopulmonary dysplasia (BPD) has increased. We conducted a multi-center investigation of the prevalence of BPD in six hospitals to investigate the epidemiology of BPD in Korea. Methods: Retrospective reviews ware performed for survival rate, prevalence of BPD of total 4,476 newborn infants who were admitted to neonatal intensive care unit in Konkuk university hospital, Sung-Ae General hospital, Kangbuk Samsung hospital, Chung-Ang university hospital, Konyang university hospital, and Gangneung Asan hospital between June, 2005 and May, 2007. By Ogawa, BPD was defined as oxygen dependency at 28 days after birth, with respiratory distress symptoms and the change of chest x-ray finding, and classified as 6 subtypes. Classic BPD was defined as oxygen dependency at 36 weeks of postmenstrual age. Results: Survival rate at 28 day after birth was 98.7%. BPD infants by Ogawa classification were 70 (1.6% of overall newborn infants), classic BPD infants were 30 (0.7%). Especially, among 237 preterm infants with birth weight less than 1,500 gram who survived to 28 days of life, 60 (25.3%) had BPD by Ogawa classification and 23 (9.7%) had classic BPD. In Ogawa classification, infants with RDS as type I and II, were 17 infants (24.3%) and 44 infants (62.9%). Home oxygen therapy was performed 8 infants (11.4%). Prevalence of retinopathy of prematurity was 35 infants (50.0%), necrotizing enterocolitis was 3 infants (4.3%), and intraventricular hemorrhage was 6 infants (8.6%). Conclusion: Prevalence of BPD infants was 1.6% of overall newborn, 25.3% of preterm infants with birth weight less than 1,500 gram. Among 70 BPD infants, BPD by Ogawa classification with history of RDS as type I and II were 24.3%, 62.9% as the majority of BPD. This study would be the first report of epidemiology of Korean BPD infants by multi-center study.

Signed-DLMS 적응 알고리즘 이용한 무선 중계 간섭 제거기

유태훈(Tae-Hoon Yoo),우대호(Dae-Ho Woo),김주완(Dae-Ho Woo),하성희(Sung-Hee Ha),반지훈(Ji-Hun Van),이종현(Jong-Hyun Lee) 대한전자공학회 2007 대한전자공학회 학술대회 Vol.2007 No.7

In this paper, we study the signed- DLMS adaptive algorithm of wireless repeater for solving shadow region due to propagation between base station and mobile station. The the signed-DLMS algorithm reduces interference signals from multipath and solves the oscillation problem of repeater by estimation and cancellation. To efficiently reject interference signal. the signed-DLMS adaptive algorithm is applied. The computational complexities of the signed-DLMS are reduced verse standard LMS algorithm. Wireless ICS repeater based on signed-DLMS reduces the cost and is able to increase channel capacities.

Nanogenerators: Fully Rollable Transparent Nanogenerators Based on Graphene Electrodes (Adv. Mater. 19/2010)

Choi, Dukhyun,Choi, Min-Yeol,Choi, Won Mook,Shin, Hyeon-Jin,Park, Hyun-Kyu,Seo, Ju-Seok,Park, Jongbong,Yoon, Seon-Mi,Chae, Seung Jin,Lee, Young Hee,Kim, Sang-Woo,Choi, Jae-Young,Lee, Sang Yoon,Kim, Jo WILEY-VCH Verlag 2010 ADVANCED MATERIALS Vol.22 No.19

<B>Graphic Abstract</B> <P>The cover shows an image of fully rollable transparent nanogenerators synthesized using chemical vapor deposition grown large-scale graphene sheets as transparent electrodes and piezoelectric ZnO nanorod arrays. Sang-Woo Kim, Jae-Young Choi, and co-workers report on p. 2187 the electrical and structural stability of the nanogenerators, with excellent charge scavenging performance under external mechanical loads such as bending and rolling. This study shows that graphene-based nanogenerators are very promising for self-powered rollable transparent device applications. <img src='wiley_img_2010/09359648-2010-22-19-ADMA201090066-content.gif' alt='wiley_img_2010/09359648-2010-22-19-ADMA201090066-content'> </P>

Construction of Stably Transformed Bm 5 Cells by Using Autographa californica Nuclear Polyhedrosis Virus IE 0 Gene

Cho, Eun Sook,Jin, Byung Rae,Sohn, Hung Dae,Choi, Kwang Ho,Kim, Soung Ryul,Kang, Seok Woo,Yun, Eun Young,Kim, Sang Hyun,Kim, Keun Young,Je, Yeon Ho,Kang, Seok Kwon 한국잠사학회 1998 한국잠사곤충학회지 Vol.40 No.2

To construct transfurmed Bm5 cells, Autographa californica nuclear polyhedrosis virus(AcNPV) IE1 gene, an immediate early viral gene was firstly used in this study. AcNPV IE1 gene, which shares on 95.3% nucleotide sequence homology with Bombyx mori nuclear polyhedrosis virus (BmNPV) IE1 gene, was isolated and cloned into pBluescript. Neomycin gene from pKO-neo was inserted under the control of the IE1 promoter to yield pAcIE1-neo. The plasmid pAcIE1-neo was transfected into Bm5 or Sf9 cells, and neomycin-resistant cells were selected in TC100 medium containing 10% fetal bovine serum (FBS) and 1 mg/ml G4l8 for two weeks. Individual clones were picked and each was amplified for further characterization. The genomic DNA from neomycin-resistant cells was isolated and characterized by PCR using AcNPV IEI gene-specific primers and by Southern blot analysis using neomycin gene probe. We concluded that AcNPV IE1 gene was functional in B. mori-derived Bm5 cells as well as Spodoptera fugjprrda-derived Sf9 cells to produce stably-transformed insect cells

THE EFFECT OF H2S IN HYDROGEN MEMBRANE WITH Pd-ZrO₂ LAYER USING CO-SPUTTERING METHOD

Sung-Wook Lee,Jin-Woo Park,Chun-Boo Lee,Dong-Wook Lee,Jong-Soo Park,Shin -Kun Ryi,Sung-Hyun Kim 한국신재생에너지학회 2013 AFORE Vol.2013 No.-