${Fe_3}Al-4Cr$ 합금의 고온산화

김기영,이동복,Kim, Gi-Young,Lee, Dong-Bok 한국재료학회 2001 한국재료학회지 Vol.11 No.1

Intermetallics of Fe-28%Al($Fe_3Al$) and Fe-28%Al-4%Cr($Fe_3Al-4Cr$) were oxidized at 1073, 1273 and 1473k in air for up to 17 days. The oxidation resistance of$Fe_3Al-4Cr$ was basically similar to or better than that of $Fe_3Al$. The oxide scales formed on $Fe_3Al$ consisted essentially of pure ${\alpha}-AL_2O_3$, while those formed on $Fe_3Al-4Cr$ consisted of ${\alpha}-AL_2O_3$ having dissolved iron and chromium ions. The preferential outward diffusion of substrate elements to form the outer oxide layer led to the formation of Kirkendall voids at the oxide-matrix interface. The scales formed on $Fe_3Al(-4Cr)$ were thin and dense up to 1273K, but they spalled easily at 1473K, accompanied by more weight gains.

퓨록산의 고정화 및 알카인 생성을 위한 퓨록산이민 유도체의 합성과 기체상 분해 반응

김기영,황광진,Kim, Gi-Young,Hwang, Kwang-Jin 대한화학회 2009 대한화학회지 Vol.53 No.1

미세술기를 이용한 정계정맥류절제술이 정자 핵 내 DNA Integrity에 미치는 효과

김기영,이재석,지희준,김종현,Kim, Gi-Young,Lee, Jae-Seok,Chi, Hee-Jun,Kim, Jong-Hyun 대한생식의학회 2010 Clinical and Experimental Reproductive Medicine Vol.37 No.3

목 적: 인간 정자 핵 내의 DNA integrity는 배아의 발달 및 임신 유지에 중요한 역할을 하여 DNA integrity가 손상된 경우 불임과 유산의 원인이 된다고 하며, 정계정맥류는 DNA 손상을 일으키는 대표적인 원인 중 하나이다. 본 연구에서는 미세술기를 이용한 정계정맥류절제술로 정계정맥류를 교정을 하였을 때 정자 핵 내 DNA integrity가 어떠한 영향을 받는지에 대하여 알아보았다. 연구방법: 2006년 4월부터 2007년 4월까지 불임을 주소로 미세술기를 이용한 정계정맥류절제술을 받았던 18명의 환자에서 수술 전 후에 정액검사의 다른 지표들과 함께 정자 핵 내 DNA integrity가 어떻게 변화하였는지 조사하였다. 정자 핵 내 DNA integrity를 측정하는 방법으로 comet assay를 시행하였고, comet assay를 통한 DNA 손상 정도는 DNA fragmentation index (DFI)로 나타내었다. 결 과: 수술 후 4개월에 모든 환자에서 재발의 소견은 보이지 않았으며, DNA 손상 정도를 나타내는 평균 DFI는 수술 전에 19.3%, 수술 후에 13.7%로 유의한 변화를 보였다. 수술 전 DFI가 10 이상으로 비정상인 14명의 환자들 중 12명 (85%)에서 개선 소견을 보였으나, 수술 전 DFI가 10 미만인 정상 환자 4명에서는 1명 (25%)만이 개선 소견을 보였다. 수술 후 정자의 밀도, 운동성, 생존성에서 호전 양상을 보였으나 유의한 차이는 없었다. 결 론: 미세술기를 이용한 정계정맥류절제술을 통한 수술적 교정은 정액검사상의 다른 지표의 개선 뿐 아니라, 정자 핵 내 DNA 손상을 감소시킬 수 있다. 이상에서 정계정맥류의 수술적 교정으로 정자 핵 내 DNA integrity의 개선을 기대할 수 있으며, 이는 보다 양호한 정자를 많이 얻을 수 있어 자연임신이나 보조 생식술의 성공 가능성을 높일 수 있다는 점을 제시한다. Objective: Human sperm nucleus DNA damage may negatively affect pregnancy outcome, and the spermatozoa of infertile men have more DNA damage than that of fertile men. The aim of this study was to evaluate the effect of microsurgical varicocelectomy on human sperm nucleus DNA integrity. Methods: We reviewed the medical records of 18 subfertile male patients who underwent microsurgical varicocelectomy at our hospital from April 2006 to April 2007. Varicocele was diagnosed by physical examination and Doppler ultrasound. Standard semen analysis was performed in 18 patients before and 4 months after microsurgical varicoceletcomy using a computer assisted semen analyzer. Sperm nucleus DNA integrity was assessed by a single-cell gel electrophoresis (comet assay). Results: No recurrence of varicocele was observed after 4 months later. The DNA fragmentation index improved after varicocelectomy compared with pre-operatively (19.3 versus 13.7%, respectively, p<0.05). Semen analysis parameters (total count, concentration, motile sperm, viability, strict morphology) increased after varicocelectomy, but the difference did not reach statistical significance. Conclusion: Our data suggest that microsurgical varicocelectomy can improve semen analysis parameters and human sperm nucleus DNA integrity in infertile men with varicocele.

3시간 방화도어를 구비한 고층건축물, 장애인, 의료 및 다중이용 시설의 화재시 비상구난용 엘리베이터에 관한 연구

김기영(Gi-Young Kim),장승호(Seung-Ho Jang) 한국생산제조학회 2022 한국생산제조학회지 Vol.31 No.1

거주자 판정 남용 및 조세피난처를 통한 역외탈세에 대한 인식도 연구

김기영(Gi-Young Kim),홍정화(Jung-Hwa Hong) 한국무역연구원 2014 무역연구 Vol.10 No.4

The purpose of this study is to, by modifying and revising a resident determining criteria on current Income Tax Law and clarifying a legislative regulation, examine the extend of perception to practical counterplan which can prevent tax avoidance using pretense to non-resident and offshore tax evasion using Tax Heaven. Summarize of this results are as below. First, about awareness for status of offshore tax evasion, opinions that responding method for offshore tax evasion by current Korean tax system is not enough were appeared. Both revenue officers and tax agents agreed with low responding of current tax system for offshore tax evasion. Second, on current law, with reference to the importance rank about problems for a resident determining criteria, opinions for that ‘on current law, regulations and interpretations for concept of resident can t define concept of resident clearly ’ took the 1st rank by appearing highly. Third, with reference to the importance rank about reason for offshore tax evasion possibility, since opinions about ‘lack of evidence for offshore tax evasion’ took the 1st rank by appearing highly, this study can find out that lack of providing relevant information which can be a beginning approach to the suspicion of offshore tax evasion can be the biggest reason. Forth, with reference to the importance rank about improvement plan for resident decision to prevent offshore tax evasion, the concept of ‘having their own address, that is, “when having a job which is essential to stay more than 1 year continuously” should be defined clearly.’ took the 1st rank by appearing highest. Fifth, with reference to the importance rank for international counterplan to prevent offshore tax evasion, opinions for ‘reinforcement of international cooperation; vitalization of information exchange with other countries and so on ’took the 1st rank by appearing highly. Sixth, with reference to the counterplan which can be done domestically to prevent offshore tax evasion, opinions for ‘foundation of Tax Heaven related law and reducing of actual burdening tax rate when deciding Tax Heaven’ took the 1st rank by appearing highly.

장애인 체육활동에 대한 직장인의 태도

김기영(Kim Gi-Young),한희창(Han Hee-Chang),김도진(Kim Do-Jin) 한국체육과학회 2006 한국체육과학회지 Vol.15 No.3

This study is for the basic information to the basic analyzing attitude of on-the-job about capped sports activities with comparing with another factor. We drew conclusions by analyzing Independent t-test and one-way ANOVA(Turkey), 330copies to compare the difference of understanding of on-the-job on condition that the objects are only the people on-the-job. First, there is no significant difference in all fields in attitude of on-the-job's sports activities according to their sex. Second, there are significant differences in cognitive effect according to their age. Third, there are significant differences in cognitive effect and affective effect according to their scholarship. Fourth, there is no significant difference in all fields according to their place of residence. Fifth, there are significant differences in cognitive effect according to their club activities. Sixth, there is no significant difference in all fields according to their service for the handicapped. Seventh, there are significant differences in psycho-motor effect according to their home background. Eighth, there are significant differences in all fields according to their job and religion I'd like to inform you some of proposal through this study's conclusion. I think that the attitude of on-the-job who charges essential work of community speaks for our society. Specially, it's not calculous how the attitude of on-the-job about the handicapped has an effect on our society. Also, the attitude of the handicapped and change of thinking are able to charge 'contact agent' to make the society the one and protect the weak of society. Therefore, it is important that make social method for the weak and encourage to participate on-the-job through social park. I think that the change of thinking in long term and making social method have a positive effect on our society better than now with concern about the handicapped and the participation of non-handicapped.

T-DMB 동일 채널 중계기의 주파수 영역에서 ICI를 고려한 적응형 채널 추정과 결정지향 잡음 제거

김기영(Gi-Young Kim),유상범(Sang-Burm Ryu),유흥균(Heung-Gyoon Ryu) 한국전자파학회 2012 한국전자파학회논문지 Vol.23 No.4

최근 OFDM 시스템의 T-DMB 동일 채널 중계기에서 궤환 신호를 제거하여 송신 출력을 증강시키고, 등화기를 사용하여 ICI(Inter Carrier Interference)를 제거함으로써 시스템 성능을 개선하기 위하여 노력하였다. 그러나 T-DMB 동일 채널 중계기의 경우, 성상도 번짐 현상으로 수신 단말기에서 완벽하게 신호 품질이 개선되지 않고 있다. 그러므로 본 논문에서는 성상도 번짐 현상을 억압하기 위하여 파일럿(PRS)을 이용하여 주파수 영역에서의 ICI를 고려한 적응형 채널 추정과 결정지향 잡음 제거 기법을 제안함으로써 단말기에서 수신 품질을 확보한다. T-DMB 단말기에서 요구되는 QoS(Quality of Service)를 확보하기 위하여 동일 채널 중계기에서 SNR과 BER을 평가하고, 시뮬레이션을 통하여 검증하였다. 시뮬레이션 결과를 통하여 back-off=9 dB 상태에서 위상 잡음 -18 dBc의 경우, 위상 잡음을 보상하여 수신기에서 SNR=14 dB 이하에서 BER=10^-5의 성능을 만족할 수 있다. Recently, many papers have been proposed in order to improve the OFDM system performance in T-DMB DOCR (Digital On Channel Repeater), by using removing the feedback signal so that the transmitter power can be increased or by using the equalizer to remove ICI. Despite these efforts, however, signal quality at the receiving terminal has not been improved because of constellation smearing in T-DMB DOCR. In this paper, in order to suppress constellation smearing, we propose an effective equalizer algorithm that can improve system performance. We perform adaptive channel estimation and non-coherent decision directed noise cancellation method that can estimate the channel subsequently during data symbols period in the frequency domain. So we can obtain better quality of the signal at the receiving terminal. In order to secure QoS(Quality of Service) required in T-DMB handsets, we evaluate SNR and BER in T-DMB DOCR(Digital On Channel Repeater) and verified by simulation. In this simulation results, this system is satisfied the performance of BER=10^-5 at less than SNR=14 dB at the receiver after compensation of phase noise -18 dBc.

내러티브를 통해 살펴본 국제뉴스 현지화 현상

김기영(Kim, Gi Young) 한국번역학회 2013 번역학연구 Vol.14 No.2

국제뉴스 현지화와 그 양가적(ambivalent) 측면

김기영(Kim, Gi Young) 한국번역학회 2014 번역학연구 Vol.15 No.1

동아리 여가활동 참여와 대학생활 만족도의 관계

김기영 ( Gi Young Kim ) 오산대학교 학생생활연구소 2001 학생생활연구 Vol.6 No.-