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.

Comparison of Hanwoo with Holstein of OPU derived Embryo and Offspring Production

Jong‐In Jin,Byung‐Hyun Choi,Seong‐Su Kim,Hyun‐Tae Jo,Il‐Keun Kong 한국동물생명공학회(구 한국동물번식학회) 2011 발생공학 국제심포지엄 및 학술대회 Vol.2011 No.1

The objective of this study was to evaluate the comparison of production efficiency of oocytes and OPU (ovum pick‐up) derived embryos of Hanwoo with Holstein. The OPU session of each species (6 cows) was carried out from the Hanwoo (106 sessions) and Holstein (114 sessions) at intervals of 3 4 days (2 times per week) for 3 months. Cumulus‐oocyte‐complexes (COCs) retrieved were classified into 4 grades by the status of oocyte cytoplasm and cumulus cells. The COCs collected were matured in vitro in TCM‐199 supplemented with 10% FBS, 10 mg/ml FSH and 1 mg/ml estradiol‐ 17β in 5% CO2 and over 99% humidity for 24 h. After 24 h co‐incubation with post‐thaw sperm, the presumed zygotes were cultured in CR1aa medium with 4 mg/ml BSA for 3 days and then changed CR1aa medium with 10% of FBS for another 3 4 days. The Mean number of aspirated follicles and collected oocytes were not significantly different between Hanwoo and Holstein spacies (10.4±0.42 vs. 11.4±0.41 and 7.5±0.38 vs. 6.1±0.37 per session). But the collection rate of oocytes from aspirated follicles were significantly higher in Hanwoo (72.8%) than that in Holstein (53.6%) (p< 0.05). Furthermore, the average number of good quality oocytes (Grade I and II) was 5.9±0.28 and 4.1±0.27 (Mean±SD), and the cleavage rate and the development rate to blastocysts was significantly (p<0.05) higher in Hanwoo (40.0%) than Holstein (21.6%). The OPU derived embryos of Hanwoo were transferred 83 times into 52 recipients and then 42 calves were produced from 44 pregnancy recipients. In conclusion, the efficiency of OPU derived embryo was significantly different between Hanwoo and Holstein species. In vitro culture system for OPU derived embryo production should be optimized for industrialization and the improvement of livestock.

Application of Artificial Insemination Technology for Dairy Breeding in Mongolia

Hyun‐Tae Jo,Jong‐In Jin,Seong‐Su Kim,Byung‐Hyun Choi,Tumor Baldan,Jung‐Gyu Lee,Yun‐Shik Kim,Sam‐Churl Kim,Il‐Keun Kong 한국동물생명공학회(구 한국동물번식학회) 2011 발생공학 국제심포지엄 및 학술대회 Vol.2011 No.1

This study was focused on improvement of milk production in Mongolia dairy industry by artificial insemination (AI) technology, of which was supported from ODA project of KOICA in Republic of Korea. The study was started from January 2009 to present and 3rd years in this year. So, all data, especially synchronization and pregnancy of dairy cows (Holstein) will be summarized in final result in this year. For synchronization, total 81 dairy cows selected from 4 private farms that were 38, 30, 8 and 5 in Undarmal milk, Onjin (Enkhbayer), Jargalant, and BRM School, respectively. All the dairy cows were injected intramuscular (IM) of 5 ml PGF2α in the vulva and detected estrus 2 to 3 days after PGF2α injection. Total 78 out of 81 dairy cows (96.3%) were detected estrus by only 1 time injection of PGF2α. The dairy cows that were induced estrus, inseminated with 0.5 ml dairy frozen semen by conventional AI techniques. The pregnancy diagnosis of the AI dairy cows was detected by uterus palpation after 60 days of insemination. Total 75 from 78 inseminated dairy cows (90.1%) were diagnosis pregnant. The estrus induction and pregnant rate were very effective using PGF2α injection and conventional AI techniques in Mongolia dairy cow. The results indicated that AI after estrus induction in Mongolia dairy cows could be applied to dairy breeding technology to improve the breeding efficiency and milk production.

麻黃의 사람 비점막 섬유아세포 monocyte chemotactic protein 중 MCP - 1 , MCP - 2 , 및 MCP - 3 분비에 대한 효과

김현미,이향숙,김정선,조정제,유영천,안현종,최훈,임강현 대한본초학회 2002 大韓本草學會誌 Vol.17 No.1

Recent reports have proposed that Ephedrae Herba may modulate the immune response on allergy or asthma. Human nasal mucosal fibroblasts are a rich source cytokines, inflammatory mediators, and chemokines. Chemokines are important for the recruitment of leukocytes to sites of infection, which is essential in host defense. Objectives : The objective of this study was to investigate the effect of Ephedrae Herba on the release of the chemokines such as monocyte chemotactic protein(MCP)-1, MCP-2, and MCP-3 in human nasal mucosal fibroblasts after stimulation with cytokines like tumor necrosis factor -α(TNF-α), interferon-γ(IFN-γ), and interleukin -1β(IL-1β).

원위 대퇴골의 고립성 골연골종에서 발생한 속발성 연골 육종 1례 보고

정필현,황장수,강석,김용민,오형호,채동주,김종필 동국대학교 경주대학 1996 東國論集 Vol.15 No.-

연골육종은 비교적 서서히 자라며 늦게 전이하는 악성 연골 종양으로 알려져 있다. 골 연골종에서 발생한 속발성 연골육종은 발생빈도는 드물며 타부위로의 전이가 적고 악성도가 낮은 경우가 많아 적합한 수술적 치료로서 좋은 예후를 보이는 것으로 보고되고 있다. 본 동국대학교 정형외과학 교실에서는 우측 대퇴골 원위부 골간단부에 생긴 고립성 골 연골종에서 이차적으로 발생한 연골육종을 치험한 바 문헌고찰과 함께 보고하는 바이다. A case of Secondary Chondrosarcoma Arising from Solitary Osteochondroma of the Distal Femur Department of Orthopaedic Surgery, College of Medicine, DongGuk University Phil Hyun Chung M.D., Jung Su Hwang M.D., Suk Kang M.D., Yang Mln Kim M.D., Hyung Ho Oh M.D., Dong Ju Chae M.D., Jong Pil Kim M.D. Chondrpsarcoma is a malignant cartilage-forming tumor that grows slowly and metastasis of this tumor occurs in late stage. Secondary chondrosarcomas arising from a solitary osteocartilaginous exostosis are rare and those have a better prognosis than other chondrosarcomas, and they rarely metastasize. We present our experience with a case of secondary chondrpsarcoma arising in solitary osteochondroma of distal metaphysis of right femur with clinical details.

일본제국대학(日本帝國大學)의 조선유학생(朝鮮留學生) 연구(硏究)(1) -경도제국대학(京都帝國大學) 조선유학생의 현황, 사회경제적 출신 배경, 졸업 후 경력을 중심으로

정종현 ( Jong Hyun Jeong ),( Mizuno Naoki ) 성균관대학교 대동문화연구원 2012 大東文化硏究 Vol.80 No.-

이 글은 개교(1897) 이래 1945년 8월 15일까지 교토제국대학의 조선인 유학생 졸업자 236명의 명단을 추출하고 그들의 학부별 현황, 사회경제적 배경 및 출신고 교, 졸업 이후 식민지 사회에서의 사회적 경력과 해방 이후 남북한에서의 사회적 역 할 등을 다양한 자료를 통해 정리하여 목록화하고 해제한 연구이다. 1년 동안 교토 대학 방문 연구를 통해 수행된 본 연구의 목록은 교토제국대학이 발간한 공식자료 와 당대 조선 유학생들이 생성한 자료, 해방 이후 재일조선인사회의 교토대학 출신 들이 남긴 자료, 아직 생존해 있는 교토제국대학 출신의 백종원(白宗元)(1948, 경제학부졸(經濟學部卒)), 강상균(姜祥均)(1950, 법학부졸(法學部卒)) 두 졸업생과의 인터뷰를 통해 구성한 구술자료 및 다양한 회고록과 고등문관시험 합격자의 총독부 신원조회, 조선총독부 직원록, 각종 인명사전 등을 기반으로 하여 작성되었다. 이들 자료의 분석을 통해 식민지 유력자 집단의 교육을 통한 재생산의 실상을 확인할 수 있었으며, 졸업 이후 제국대학 출신 자들의 사회적 경력이 대부분 관료로 이어지고 있는 점을 논증함으로써 식민지 권력과 제국대학 출신 지식인 집단의 밀월관계를 확인할 수 있었다. 동시에 그들의 의 식이 제국대학 출신의 특권의식과 피식민지인으로서의 분노 사이에서 균열되며 식 민지 권력과 불화하는 측면을 확인할 수 있었다. 전체적인 이력의 조사를 통해서 식 민지 및 남북한 사회의 제영역에서 그들이 사회적 중추를 형성하고 있다는 점을 논증할 수 있었다. 본 연구를 향후 여타 제국대학으로 확장하여 제국대학의 조선인 유학생 전모를 파악하는 것이 향후의 과제이다. The purpose of this study was to examine Korean students who studied at Kyoto University in Japan. A list of 236 Korean students who graduated from that university since its foundation in 1897 till August 15, 1945, was obtained, and a wide variety of materials were analyzed to investigate the state of their departments, their socioeconomic background, alma mater, social career in the colony after graduation and social roles in South or North Korea after the liberation of the nation to prepare their bibliographical notes. The bibliography was prepared by visiting the university for a year and based on the official data released by the university, data provided by contemporary Korean students studying there, and data offered after the liberation of the nation by Korean residents in Japan who graduated from that university. And additional data were utilized: oral statements of two graduates from that university, various memoirs and biographical dictionaries. Two graduates who were still alive were interviewed to obtain their oral statements. One was Baek Jong-won who graduated in 1948 from the college of economics, and the other was Kang Sang-kyun who graduated in 1950 from the college of laws. Besides, a relevant organization was asked to confirm the successful applicants for the higher civil official examination administered by the then government-general, and the staff list of the Joseon government-general was consulted as well. The analysis of these data made it possible to check how contemporary influential people continued to be produced through education in the colony, and it showed that as for the social career of the graduates of Kyoto University, most of them became bureaucrats, which indicated the honeymoon relationship between contemporary power of the colony and the intellectuals who graduated from that university. At the same time, it``s found that they were torn between the sense of privilege as graduates of Kyoto university and wrath as colonials, which implied that they were in conflicts with contemporary power. As a result of analyzing their entire career, it``s found that they were leading figures not only during the Japanese occupation but in every field of South Korea and North Korea. In the future, it``s required to examine Korean students at other Japanese universities during the Japanese occupation to offer an overview of their life and career.

1998년과 2007년 사이 12∼13세 남녀 청소년의 체격, 골격성숙도, 체력 비교

송종국(Jong Kook Song),채서연(Seo Yeon Chae),채주희(Joo Hee Chae),김현배(Hyun Bae Kim),강효정(Hyo Jung Kang) 한국사회체육학회 2008 한국사회체육학회지 Vol.0 No.34

The purpose of the present investigation was to compare physique, skeletal maturation and physical fitness in Korean adolescents measured between 1998 and 2007. Subjects participated in the study were a total of 473 Korean adolescents aged 12 to 13 years. In 1998, 349 adolescents were selected from a middle school, located in Sungnam city and 124 middle school students aged 12-13, located in Yongin city were participated in 2007. All measurements were conducted by one of the reseachers (Jong-Kook Song) with two different group of investigators between 1998 and 2007. Anthropometric characteristics were body mass, body height, sitting height, circumferences taken at sites of upper arm, flexed upper arm, chest, waist, hip, thigh, and calf, bone breadth taken at the sites of humerus, and femur, skinfold thicknesses taken at the sites of triceps, subscapular, suprailiac, thigh and medial calf. Skeletal maturity was assessed by TW3 (Tanner et al., 2001). Maturity scores for Radius-Ulna-Short bones (RUS) and bone age were calculated. Physical fitness parameters included flamingo balance, sit and reach, grip strength, sit-ups, standing long jump, bent arm hang, 50m shuttle run and multi-stage shuttle run. All data were analyzed by SAS Enterprise 3.0. Means and standard deviations were calculated by descriptive statistics. Independent t-test was applied to compare dependent variables between measurements. The level of significance was set at p<0.05. Results of the study showed that male adolescents aged 12-13years in 2007 had significantly higher (p<0.0001) femur diameter than adolescents in 1998. Male adolescents in 2007 had higher (p<0.05) chest, waist and calf circumferences than those of adolescents in 1998. Although no difference were found for RUS and bone age in males adolescents between 1998 and 2007 female adolescents in 2007 were significantly delayed for their skeletal maturity level compared to female adolescents in 1998. For physical fitness parameters male adolescents aged 12 years in 2007 performed better for flamingo balance (p<0.01), and 50m shuttle run (p<0.05) than those of adolescents in 1998. However, stand long jump and bent arm hang were significantly decreased in male adolescents in 2007. Female adolescents aged 12-13 years in 2007 had significantly higher flamingo balance, but female adolescents aged 12 years in 2007 performed significantly less for standing long jump (p<0.0001), bent arm hang (p<0.001) and speed (p<0.05) than those of female adolescents in 1998. In conclusions this study suggest that chest circumference for both male and female adolescents in 2007 was significantly higher than those in 1998. Skeletal maturity for female adolescents in 2007 were significantly delayed compared to female adolescents in 1998. Further study is needed to evaluate consistent various.

한국의 정신분열병 외래 환자의 직ㆍ간접비용

박종익,송선희,서동우,장현종,이종국,장안기,김윤,이철,홍진표 大韓神經精神醫學會 2000 신경정신의학 Vol.39 No.3

연구목적 : 정신분열병 외래 환자의 직접 비용과 간접 비용을 추산해 보고, 의료 자원의 적절한 운용과 효과적인 배분을 위한 보건 정책의 기초자료로 사용하고자 한다. 방 법 : 정신분열병 진단을 받은 289명의 환자를 대상으로 6개월간 외래를 방문하면서 사용한 의료비와 시간을 조사하여 직접 비용을 추산하였고, 이 기간 동안 소실된 생산성을 간접 비용으로 환산하였다. 만성질환인 관상동맥 질환을 앓고 있는 환자 82명을 대조군으로 하여 비용을 비교하였다. 결 과 : 정신분열병 환자의 실업률은 72.1%였으며, 직장을 가지고 있는 경우에도 단순노무직의 비율이 64.5%로 매우 높았다. 정신분열병의 직접 비용은 평균 81.5만원으로 관상동맥 질환의 평균 71.5 만원보다 상대적으로 많이 추산되었으나 유의하지는 않았다. 간접 비용은 평균 645.6만원, 258.9 만원으로 정신분열병군이 2.5배 정도 높았다. 결 론 : 정신분열병은 다른 만성질환에 비하여 상대적으로 매우 고비용이 요구되는 질환이며, 보다 체계적인 비용의 추산을 통하여 양질의 정신 보건 서비스를 제공할 수 있는 토대가 마련되어야 할 것이다. Objectives : We have aimed to estimate the direct and indirect costs of treating out-patients with schizophrenia in Korea, to use this fundamental data for the effective management and proper distribution of the medical resource. Method : To estimate the direct cost, we surveyed the medical cost and time of two hundred and eighty-nine out-patients with schizophrenia for six months. And the lost productivity as many months was converted into the indirect cost. Those of eighty-two coronary heart disease patients were also estimated as a comparison group. Results : An unemployement rate of schizophrenic patients was 72.1 percent. Moreover the ratio of the laborer in the sample was, even if employed, 64.5 percent. The mean direct cost of schizophrenic patients was, about 815,000 won, higher than that of coronary heart disease, 715,000 won however it was not statistically significant. The former was also estimated 2.5 times more than the latter for the indirect cost, or 6,456,000 won versus 2,589,000 won. Conclusion : Schizophrenia is a relatively costly illness compared to other chronic illness, so the systematic estimation of the cost is necessary to provide mental health service of high quality.

열전퇴형 적외선 검출기의 개발연구

유호종,이현철,김진섭,이종현 경북대학교 센서기술연구소 1997 연차보고서 Vol.1997 No.-

열전퇴형 적외선 검출기의 개발연구를 위해, 센서의 핵심 구성요소인 열차단막, 열전퇴 및 적외선 흡수체에서 각각 요구되는 특성들을 검토하였고, 이들 특성을 실현하는 공정기술의 검증을 위한 시험소자로서 적외선 열원 대신에 Pt 히터 또는 NiCr 히터가 내장된 Bi-Sb 열전쌍 또는 열전퇴를 제작하였으며, 이들의 열응답 특성을 주로 고찰하였다. Pt 히터 저항에 대한 다이아프램 형성전후의 전류-전압 특성 차이 및 이 히터가 내장된 Bi-Sb 열전쌍에 대한 공기 및 진공중에서의 열감도 변화로부터 Si_3N_4/SiO_2/Si_3N_4다이아프램의 열차단 특성을 확인할 수 있었고, 또한 히터의 저항 온도계수를 측정함으로써 인가된 전력에 의한 Pt 히터의 온도를 알 수 있었다. Pt 히터가 내장된 Bi-Sb 열전쌍 시험소자의 열기전력은 히터와 열전쌍 사이의 거리가 증가함에 따라 지수함수적으로 감소하였고, 열전쌍의 열전계수는 약 97㎶/K였다. Pt 또는 NiCr 히터가 내장된 Bi-Sb 열전퇴 시험소자의 전압감도는 열전퇴를 구성하는 열전쌍의 개수가 증가함에 따라 증가하였고, 히터와 열전퇴의 고온 접합부 사이의 거리 및 고온 접합부와 실리콘 림 사이의 거리에 크게 의존하였으며, 또한 진공중에서의 전압감도가 공기중에서의 전압감도보다 더 크게 나타났다. 상기 결과를 바탕으로 하여 열전퇴형 적외선 센서의 시험제작을 위한 공정 설계와 공정용 마스크의 설계 및 제작을 완료하였다. For the development of a thermopile-type infrared detector, the respective characteristics required in thermal isolation layer, thermopile and infrared absorber, which are the core components of the detector, were studied first of all. The Bi-Sb thermocouples and thermopiles with Pt- or NiCr-heater instead of the infrared radiation source have been fabricated as the test devices for the verification of the process technologies to fulfill respective characteristics, and their thermal responsivities were mainly investigated. The thermal isolation of Si_3N_4/SiO_2/Si_3N_4-diaphragm was confirmed by Ⅰ-Ⅴ characteristics difference of the Pt-heaters before and after the diaphragm formation, and the thermal sensitivities change of the Bi-Sb thermocouples in the air and vacuum. It could be known that the thermal loss in the heater is caused by the air, and the heater temperature with input power could be estimated by the measurement of the resistance temperature coefficient of Pt-heater. The thermoelectric voltage of the Bi-Sb thermocouple with Pt-heater decreased exponentially as the distance between heater and thermopile increased, and its thermoelectric coefficient was about 97 ㎶/K. The voltage responsivity of the Bi-Sb thermopile with Pt- or NiCr-heater increased as the number of thermocouples increase, was strongly dependent on the distance between heater and hot junction of the thermopile, and between hot junction and silicon-rim, and the voltage responsivity in the vacuum was higher than that in the air. On the basis of the above results, the process design and preparation of the process mask set for the test fabrication of a thermopile-type infrared sensor have been completed.

민간투자 사업시행자 선정절차 모델 개발

한현종,황지선,신종현,이찬식 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.2

Since「the Act on Private Participation in Infrastructure(PPD)」was established in 1998, a number of projects have been procured by private-sector-initiatived system for infrastructure development. However, there are many shortcomings in the procedure of selecting project promoter for the domestic-PPI projects due to deficient regulations, lack of investment appetites, necessary skills and experiences, etc. An improved promoter selection procedure is necessary to select a competent project promoter and to foster participation of the private party. The purpose of this study is to suggest a procedural model for selecting competent project promoter. This model was made by comparing our regulations and procedures with foreign nation's. The suggested model is comprised of PQ, two phased evaluation system for proposals. To manage the overall procedure well, an involvement of professional "project promoter selection team" would be highly recommended.