신 흡수제(KoSol-5)를 적용한 0.1 MW급 Test Bed CO₂ 포집 성능시험

이정현,김범주,신수현,곽노상,이동욱,이지현,심재구,Lee, Junghyun,Kim, Beom-Ju,Shin, Su Hyun,kwak, No-Sang,Lee, Dong Woog,Lee, Ji Hyun,Shim, Jae-Goo 한국공업화학회 2016 공업화학 Vol.27 No.4

한전 전력연구원에서 개발한 고효율 아민계 습식 $CO_2$ 흡수제(KoSol-5)를 적용하여 0.1 MW급 Test Bed $CO_2$ 포집 성능시험을 수행하였다. 500 MW급 석탄화력발전소에서 발생되는 연소 배가스를 적용하여 하루 2톤의 $CO_2$를 처리할 수 있는 연소 후 $CO_2$ 포집기술의 성능을 확인하였으며 또한 국내에서는 유일하게 재생에너지 소비량을 실험적으로 측정함으로써 KoSol-5 흡수제의 성능에 대한 신뢰성 있는 데이터를 제시하고자 하였다. 그리고 주요 공정변수 운전 및 흡수탑 인터쿨링 효율 향상에 따른 에너지 저감 효과를 테스트하였다. 흡수탑에서의 $CO_2$ 제거율은 국제에너지기구 산하 온실가스 프로그램(IEA-GHG)에서 제시하는 $CO_2$ 포집기술 성능평가 기준치($CO_2$ 제거율: 90%)를 안정적으로 유지하였다. 또한 흡수제(KoSol-5)의 재생을 위한 스팀 사용량(재생에너지)은 $2.95GJ/tonCO_2$가 소비되는 것으로 산출되었는데 이는 기존 상용 흡수제(MEA, Monoethanol amine)의 평균 재생에너지 수준(약 $4.0GJ/tonCO_2$) 대비 약 26% 저감 된 수치이다. 본 연구를 통해 한전 전력연구원에서 개발한 KoSol-5 흡수제 및 $CO_2$ 포집 공정의 우수한 $CO_2$ 포집 성능을 확인할 수 있었고, 향후 본 연구에서 성능이 확인된 고효율 흡수제(KoSol-5)를 실증급 $CO_2$ 포집플랜트에 적용할 경우 $CO_2$ 포집비용을 크게 낮출 수 있을 것으로 기대된다. The absorption efficiency of amine $CO_2$ absorbent (KoSol-5) developed by KEPCO research institute was evaluated using a 0.1 MW test bed. The performance of post-combustion technology to capture two tons of $CO_2$ per day from a slipstream of the flue gas from a 500 MW coal-fired power station was first confirmed in Korea. Also the analysis of the absorbent regeneration energy was conducted to suggest the reliable data for the KoSol-5 absorbent performance. And we tested energy reduction effects by improving the absorption tower inter-cooling system. Overall results showed that the $CO_2$ removal rate met the technical guideline ($CO_2$ removal rate : 90%) suggested by IEA-GHG. Also the regeneration energy of the KoSol-5 showed about $3.05GJ/tonCO_2$ which was about 25% reduction in the regeneration energy compared to that of using the commercial absorbent MEA (Monoethanolamine). Based on current experiments, the KoSol-5 absorbent showed high efficiency for $CO_2$ capture. It is expected that the application of KoSol-5 to commercial scale $CO_2$ capture plants could dramatically reduce $CO_2$ capture costs.

대학교 재학생에서 Fatigue Severity Scale의 신뢰도 및 타당도 연구

이정현,정현석,임수미,조한별,마지영,고은,임주연,이선혜,배수진,이유진,류인균,정도언,Lee, Junghyun H.,Jeong, Hyeonseok S.,Lim, Soo Mee,Cho, Han Byul,Ma, Ji-Young,Ko, Eun,Im, Jooyeon J.,Lee, Sun Hea,Bae, Sujin,Lee, Yu-Jin,Lyoo, In Kyoon,Je 대한생물정신의학회 2013 생물정신의학 Vol.20 No.1

Objectives There are only a limited number of studies on instruments assessing fatigue in university students, although fatigue exerts negative influences on their health and academic performances and fatigue-related complaints are more frequently reported in young adults than middle-aged adults. The aim of this study was to validate the 9-item Fatigue Severity Scale (FSS) among university students including both undergraduate and graduate students in South Korea. Methods A total of 176 university students completed a battery of self-report questionnaires, including the FSS, the Brief Fatigue Inventory (BFI), the Beck Depression Inventory-II (BDI-II), the Beck Anxiety Inventory (BAI), the Medical Outcomes Study Short Form 36 version 2 (MOS-SF36v2), and the Inclusion of Community in the Self Scale (ICS). The data were collected from February of 2012 to June of 2012. The reliability, convergent validity, divergent validity, and exploratory factor analyses were conducted to assess psychometric properties of the FSS. Results The mean FSS score was 3.20 (standard deviation = 1.43). The FSS demonstrated an excellent internal consistency (Cronbach's ${\alpha}$ = 0.93) and item-total correlations ranged from 0.56 to 0.90. Correlations of the FSS with the BFI (r = 0.71, p < 0.01), BDI-II (r = 0.54, p < 0.01), BAI (r = 0.46, p < 0.01), MOS-SF36v2 physical component summary (r = -0.28, p < 0.01), MOS-SF36v2 mental component summary (r = -0.55, p < 0.01), and ICS (Spearman's rho = -0.07, p = 0.33) showed acceptable convergent and divergent validity. Exploratory factor analysis defined one underlying factor (eigenvalue = 5.67) that explained 93.50% of the total variance. Conclusions To the best of our knowledge, this is the first study to investigate reliability and validity of the FSS in university students. The FSS exhibits good psychometric properties for evaluation of fatigue among university students in South Korea. Since the FSS is easy to administer, score, and interpret, it could be a useful tool in research and practice for assessing fatigue among university students.

마블 코믹스와 마블 시네마틱유니버스에서 나타나는 재매개 현상에 대한 연구

이정현,이창욱,Yi, Jung-Hyun,Lee, Chang-Wook 한국디지털정책학회 2021 디지털융복합연구 Vol.19 No.6

본 연구는 인쇄매체가 영상매체로 재매개 되면서 콘텐츠가 변화되는 과정을 분석한다. 미디어를 통해 콘텐츠가 생산되고, 기존의 콘텐츠가 새로운 미디어에 흡수되면서 변화하는 과정을 관찰하여 재매개된 미디어의 특성을 파악한다. 재매개의 이중논리를 적용하여, 인쇄매체가 영상매체로 재매개되는 과정을 분석하고, 그 결과를 통해 매체의 변화와 변용을 이용한 재매개 방식이 디자인에 방법론에 적용될 수 있다는 가능성을 제시한다. 마블 코믹스는 마블 시네마틱 유니버스로 재매개 되었다. 아날로그 미디어가 새로운 미디어로 재매개되는 현상을 이해함으로써, 디자이너가 디자인을 할 때 재매개의 특성을 이용하여 결과물을 도출 할 수 있도록 디자인 방법론을 제시할 수 있다. 매체가 발달함에 따라 디자인의 범주도 넓어지고 있다. 본 연구를 통해 재매개를 이용한 디자인 방법론 제시되길 기대해 본다. This study analyzes the characteristics of the process of changing content as print media is remediation as video media. By applying the dual logic of remediation, we analyze the process of remediation analog media(print) into new media(video). Through the results, we present the possibility that remediation methods using changes and variations in various media can be applied to the design methodology. Marvel Comics has been remediationed as Marvel Cinematic Universe. By understanding the phenomenon that analog media is remediation as new media, Design methodologies can be presented so that designers can derive the results by using the characteristics of remediation when designing.

체외수정 및 배아이식술에서 레이저를 이용한 보조부화술의 효용성에 대한 연구

이정현,한지은,김유신,원형재,조정현,곽인평,엄진희,박은아,최윤정,이동률,윤태기,Lee, Jung-Hyun,Han, Ji-Eun,Kim, You-Shin,Won, Hyung-Jae,Cho, Chung-Hyun,Kwak, In-Pyung,Eum, Jin-Hee,Park, Eun-A,Choi, Yoon-Jung,Lee, Dong-Ryul,Yoon, Tae-Ki 대한생식의학회 2008 Clinical and Experimental Reproductive Medicine Vol.35 No.3

목 적: 보조부화술이 적용되는 좋지 않은 예후를 보여주는 선별된 환자군을 대상으로 산성 용액을 이용한 AHA 방법과 레이저를 이용한 AHL 방법의 효용성을 비교하여, 보다 효과적으로 임신율과 착상률을 높일 수 있는 보조부화술 방법을 찾고자 하였다. 연구방법: 2006년 2월부터 9월까지 체외수정 시술을 시행한 환자 중 보조부화술이 필요한 328주기를 대상으로 산성용액을 이용한 AHA 방법 (180주기)과 ZILOS-tk 레이저를 이용한 AHL 방법 (148주기)으로 나누어 시행하였다. 보조부화술을 시행한 환자군은 환자의 나이가 38세 이상이거나 투명대의 두께가 $18{\mu}m$ 이상, 기저 FSH 농도가 15 mIU/ml이상, 체외수정 시술을 3번 이상 실패한 환자, 이식하는 배아의 상태가 양호하지 않은 환자들로 이상에 적용요인이 있으면 시행하여 무작위로 보조부화술 방법간에 환자들의 임상적 특징과 임신율과 착상률을 분석하였다. 결 과: 전체 보조부화술을 시행한 환자군에 AHL 방법과 AHA 방법간에 임신율 (42.6%, 63/148 vs. 33.3%, 60/180)과 착상률 (17.4%, 82/470 vs. 16.0%, 89/556)에 유의적 차이는 나타나지 않았다. 그러나 나이가 많은 환자군인 Group 1은 임신율 (37.0%, 20/54 vs. 18.7%, 14/75)과 착상률 (14.4%, 23/160 vs. 7.1%, 15/210)이 AHL 방법이 AHA 방법보다 유의적 (p<0.05)으로 높게 나타났다. 전체 환자군이나 선별된 각 군내에 보조부화술 방법간에 환자의 임상적 특징은 유의적 차이가 나타나지 않았다. 3번 이상 체외시술에 실패한 환자군 [Group 2: 43.8% (21/48)과 31.6% (25/79)], 투명대의 두께가 $18{\mu}m$ 이상인 환자군 [Group 3: 43.8% (32/73)과 34.1% (28/82)], 이식한 배아의 질이 양호하지 않은 환자군[Group 4: 25.0% (7/28)과 14.6% (6/41)]에서는 AHL 방법이 임상결과는 좋았으나 유의적 차이는 없었다. 결 론: 레이저를 이용한 AHL 방법이 나이가 많은 환자군과 3번 이상 체외수정 시술에 실패한 환자군에서 AHA방법에 비해 높은 임신율과 착상률을 나타내었다. 결론적으로, AHL을 이용한 보조부화술이 임상적으로 보다 효과적이고 안전한 방법이라고 사료된다. Objective: To evaluate efficacy of assisted hatching by laser (AHL) and acidified Tyrode solution (AHA) in selected groups of IVF-ET patients who have a poor prognosis. Methods: From February 2006 to September 2006, total of 328 IVF-ET cycles with advanced female age (${\geq}38$ years), recurrent implantation failure (${\geq}3$ cycles), thick zona (${\geq}17{\mu}m$), and/or poor quality of embryo were randomly divided into assisted hatching by acidified Tyrode solution (AHA, n=180) and the assisted hatching using the ZILOS-tk laser (AHL, n=148) groups. Clinical outcomes were analyzed and compared between AHA and AHL group based on the patient characteristics. Results: In all AHL and AHA group, there were no significant differences in pregnancy (42.6%, 63/148 vs. 33.3%, 60/180) and implantation rates (17.4%, 82/470 vs. 16.0%, 89/556) However, in advanced female age group (Group 1), pregnancy (37.0%, 20/54 vs. 18.7%, 14/75) and implantation rates (14.4%, 23/160 vs. 7.1%, 15/210) in AHL group were significantly (p<0.05) higher than those of AHA, although there was no difference in patient parameters of both groups. And, the clinical outcome of groups with recurrent implantation failure (Group 2), thick zona pellucida (Group 3) and poor quality embryo (Group 4) were improved in AHL compared to those of AHA: 43.8% (21/48) and 31.6% (25/79) in Group 2, 43.8% (32/73) and 34.1% (28/82) in Group 3, 25.0% (7/28) and 14.6% (6/41) in Group 4, but no significance. Conclusion: The AHL improved the pregnancy and implantation rates in patients with advanced female age and recurrent implantation failure when compared to outcomes achieved from AHA. Therefore, this AHL technique may be a efficient and safe method for patients with poor prognosis.

해외 타이어 업체의 재편 전략

이정현,Lee, Jeong-Hyeon 대한타이어공업협회 2001 타이어 Vol.209 No.-

요통환자(腰痛患者)의 양도락(良導絡) 변화(變化)에 대한 임상적(臨床的) 고찰(考察)

이정현,김민수,이은용,Lee, Jung-hyun,Kim, Min-soo,Lee, Eun-yong 대한침구의학회 2003 대한침구의학회지 Vol.20 No.1

Objective : We investigated association between excessiveness and deficiency of the visceral and twelve merdians and low back pain, by checking Yangdorak. Methods : Clinical studies were done 62 patients who were treated with low back pain to Dept. of Acupuncture & Moxibustion, Hospital of Oriental Medicine in Semyung University from August 2, 2002 to August 20, 2002. We divided low back pain patients into lumbar vertebra strain, herniated nucleous pulposus(H.N.P.) degenerative spondylosis(D.J.D) and tested the potentiality of skin resistance(Yangdorak) to them. Results: 1. H.N.P. groups were more than another groups in comparing with the States over Physiological Limits and the and excessiveness of merdians. 2. In degenerative spondylosis groups, excessiveness of the F3(kidney) was to be superior. In H.N.P. groups deficiency of the H5(triple energiger) was to be superior. In lumbar vertebra strain groups, deficiency of the H5(triple energiger) and excessiveness of the F2(Liver) was to be very superior. Conclusions: We could investigate the relationship of the excessiveness and deficiency of the visceral and twelve merdians to low back spain patients by checking Yangdorak. Specially, Deficiency of the H5(triple energiger) and H4(Small intestine) may be helpful in diagnosis H.N.P..

랜덤액세스 장치의 속도성능 향상을 위한 모델추종 제어기의 적용

이정현,박기환,김수현,곽윤근,Lee, J.H,Park, K.H,Kim, S.H,Kwak, Y.K 대한기계학회 1996 大韓機械學會論文集A Vol.20 No.1

In the time optimal control problem, bang-bang control has been used becaese it is the theoretical time minimum solution. However, to improve tracking speed performance in the time optimal control, it is important to select a switching point accurately which makes the velocity zero near the target track. But it is not easy to select the swiching point accurately because of the damping coefficient variation and uncertainties of modeling an actual system. The Adaptive model following control(AMFC) is implemented to relieve the difficulty and inconvenience of this task. The AMFC and make the controlled plant follow as closely as possible to a desired reference model whose switching point can be calculated easily and accurately, assuring the error between the states of the reference model and those of the controlled plant appoaches zero. The hybrid control method composed of AMFC and PID is applied to a tracking actuator of the magneto optical disk drive(MODD) in random access devices to improve its slow tracking performance. According to the simulaion and experimental results, the average tracking time as small as 20ms is obtained for a 3.5 magneto-optical disk drive. The AMFC also can be applied for other random access devices to improve the average tracking performance.

연령에 따른 한국인 손 피부색 차이 분석

홍다검ㆍ이희경ㆍ이정현(Da Geom HongㆍHee kyung LeeㆍJeong Hyun Lee) 한국인체미용예술학회 2016 한국인체미용예술학회지 Vol.17 No.1

Recently, nail industry trends have been shifting from polish nail to gel nail. Because of the popularity of gel nail, the criteria for customers to choose colors have significantly changed. Therefore, there has been a rising demand for a nail color which goes well with skin color, not with the color of clothes, makes the hand more beautiful. Unlike a face, hand skin color isn’t corrected through makeup. Therefore, it is more difficult to find a color which is well matched with the skin tone. In this sense, the accurate analysis and classification of hand skin color which is the first step in the selection of nail color are required. However, it’s still very hard to find studies on hand skin color. To figure out the characteristics of Koreans’ hand skin color by age, this study analyzed differences in hand skin color by age after measuring the tone of the back of the hand and conducting quantitative analysis against 300 women living in Busan, Ulsan and Gyeongnam. The results revealed statistically significant difference (p.001). As the respondents were younger, a bright skin tone was observed. According to analysis on the distribution by the rank, ‘20s’ was the highest with 46% among those with a bright skin tone within top 100 ranks. In top 300 ranks, in contrast, ‘50s’ was the highest with 46% while ‘20s (8%)’ was the lowest. In terms of a skin tone, there was a considerable difference between ‘20s’ and ‘50s.’ Even though no big difference was found between ‘30s’ and ‘40s,’ a skin tone was brighter in the latter.

해양유래 초고온성 고세균 Thermococcus sp. NA1 유전체 해독과 활용

이정현,Lee, Jeong-Hyeon 한국유전체학회 2006 유전체소식 Vol.6 No.4

경찰공무원에서 외상후스트레스장애와 기질 및 성격 특성의 관계

이정현,김옥주,남윤영,신정하,이희봉,김지애,심민영,Lee, Junghyun H.,Kim, Ok Joo,Nam, Yoon-Young,Shin, Jungha,Lee, Heebong,Kim, Jiae,Sim, Minyoung 대한불안의학회 2015 대한불안의학회지 Vol.11 No.1

Objective : Police officers are exposed to job-related traumatic events and have a high prevalence of post-traumatic stress disorder (PTSD). This study examined the relationship between PTSD symptoms and dimensions of temperament and character in police officers. Method : Thirty-six police officers participating in a psychological support program were enrolled. All subjects were asked to complete a demographic questionnaire, the Impact of Event Scale-Revised (IES-R), the Temperament and Character Inventory (TCI) and other self-reported symptoms scales. Results : Among all participants (age $40.8{\pm}10.2$, men 94.4%), the rate of 'post-traumatic stress symptoms group' was 47.2%. After controlling for confounding factors, lower self-directedness scores were significantly associated with higher PTSD symptoms (${\beta}=0.6$, p=0.03) in multiple regression analysis. Conclusion : Character traits, especially self-directedness, were associated with the severity of PTSD symptoms severity. These findings may provide useful information regarding personality factors related to PTSD in police officers.