<출판저널> 연중기획 '이달의 책, 이달의 저자' 편집기획자의 말

김선혜,Kim, Seon-Hye 대한출판문화협회 2003 출판저널 Vol.332 No.-

원전 혼합배관 고주기 열피로 평가방법론의 적용성 평가

김선혜,성희동,최재붕,허남수,박정순,최영환,Kim, Sun-Hye,Sung, Hee-Dong,Choi, Jae-Boong,Huh, Nam-Su,Park, Jeong-Soon,Choi, Young-Hwan 한국압력기기공학회 2011 한국압력기기공학회 논문집 Vol.7 No.4

Turbulent mixing of hot and cold coolants is one of the possible causes of high cycle thermal fatigue in piping systems of nuclear power plants. A typical situation for such mixing appears in turbulent flow through a T-junction. Since the high cycle thermal fatigue caused by thermal striping was not considered in the piping fatigue design in several nuclear power plants, it is very important to evaluate the effect of thermal striping on the integrity of mixing tees. In the present work, before conducting detailed evaluation, three thermal striping evaluation methodology suggested by EPRI, JSME and NESC are analyzed. Then, a by-pass pipe connected to the shutdown cooling system heat exchanger is investigated by using these evaluation methodology. Consequently, the resulting thermal stresses and the fatigue life of the mixing tee are reviewed and compared to each other. Futhermore, the limitation of each methodology are also presented in this paper.

국제공동연구 PARTRIDGE를 통한 확률론적 건전성 평가 기술 개발 현황

김선혜,박정순,김진수,이진호,윤은섭,양준석,이재곤,박홍선,오영진,강선예,윤기석,박재학,Kim, Sun Hye,Park, Jung Soon,Kim, Jin Su,Lee, Jin Ho,Yun, Eun Sub,Yang, Jun Seog,Lee, Jae Gon,Park, Hong Sun,Oh, Young Jin,Kang, Sun Yeh,Yoon, Ki Seok,P 한국압력기기공학회 2013 한국압력기기공학회 논문집 Vol.9 No.1

A probabilistic assessment code, PRO-LOCA ver. 3.7 which was developed in an international co-operative research program, PARTRIDGE was evaluated by conducting sensitivity analysis. The effect of some variables such as simulation methods (adaptive sampling, iteration numbers, weld residual stress model), crack features(Poisson's arrival rate, maximum numbers of cracks, initial flaw size, fabrication flaws), operating and loading conditions(temperature, primary bending stress, earthquake strength and frequency), and inspection model(inspection intervals, detectable leak rate) on the failure probabilities of a surge line nozzle was investigated. The results of sensitivity analysis shows the remaining problems of the PRO-LOCA code such as the instability of adaptive sampling and unexpected trend of failure probabilities at an early stage.

충방전 과정중 구조가 안정한 Zr이 도핑된 LiCoO₂ 분말

김선혜,심광보,안재평,김창삼,Kim, Seon-Hye,Shim, Kwang-Bo,Ahn, Jae-Pyoung,Kim, Chang-Sam 한국세라믹학회 2008 한국세라믹학회지 Vol.45 No.3

Zirconium-doped $Li_{1.1}Co_{1-x}Zr_xO_2(0{\leq}x{\leq}0.05)$ powders as cathode materials for lithium ion batteries were synthesized using an ultrasonic spray pyrolysis method. Cyclic voltammetry and cyclic stability tests were performed, and the changes of microstructure were observed. The solubility limit of zirconium into $Li_{1.1}CoO_2$ was less than 5 mol%, and monoclinic $Li_2ZrO_3$ phase was formed above the limit. The Zr-doping suppressed the grain growth and increased the lattice parameters of the hexagonal $LiCoO_2$ phase. The Zr-dopiong of 1mol% resulted in the best cyclic performance in the range of $3.0{\sim}4.3V$ at 1C rate (140 mA/g); the initial discharge capacity decreased from 158 mAh/g to 60 mAh/g in the undoped powder, while from 154 mAh/g to 135 mAh/g in the Zr-doped powder of 1 mol% after 30 cycles. The excellent cycle stability of Zr-doped powder was due to the low polarization during chargedischarge processes which resulted from the delayed collapse of the crystal structure of the active materials with Zr-doping.

알루미늄이 첨가된 Li(Ni_1/3Co_1/3Mn_1/3-xAl_x)O₂ 양극활물질의 전기화학적 특성

김선혜,심광보,김창삼,Kim Seon-Hye,Shim Kwang-Bo,Kim Chang-Sam 한국전기화학회 2006 한국전기화학회지 Vol.9 No.2

초음파분무열분해법과 한 단계의 후열처리로 이차상이 없는 Al이 첨가된 $Li(Ni_{1/3}Co_{1/3}Mn_{1/3-x}Al_x)O_2$ (x=0.0, 0.005, 0.01. 0.05) 리튬이차전지용 양극활물질을 합성하였다. 합성된 분말은 Al의 첨가량이 많아짐에 따라서 $I_{003}/I_{104}$ 비는 감소하고 입자가 커지는 경향을 보였다. 상온에서 전류밀도 1C의 rate로 $3.0\sim4.5V$ 범위에서 충방전 시험한 결과, Al 치환량이 0.5와 1.0 at%에서는 초기용량이 180과 $184mAhg^{-1}$으로 치환하지 않았을 때의 $182mAhg^{-1}$과 차이가 없었으며, 싸이클 특성도 치환하지 않은 것과 0.5, 1.0 at% 치환한 조성에서 각각 81, 77, 81%의 방전용량이 유지되었다. 그러나 $3.0\sim4.6V$에서는 치환효과가 확실하게 나타나서, 50 싸이클 후의 치환하지 않은 것의 방전용량은 초기용량의 30%가지 감소한데 비하여 Al을 0.5 at% 치환한 것은 70%를 유지하였다. 치환에 의한 싸이클 특성 향상은 XPS 분석 결과 Al 치환이 $Mn^{3+}$의 양을 감소시켰기 때문인 것으로 사료되었다. Cathode materials of Al-doped $Li(Ni_{1/3}Co_{1/3}Mn_{1/3-x}Al_x)O_2$ (x=0.0, 0.005, 0.01 0.05) for lithium ion batteries were synthesized with ultra-sonic spray pyrolysis method and single-step heat treatment. No secondary phases were found in all synthesized powders. The intensity ratio of $I_{003}\;to\;I_{104}$, however, slightly decreased and the particle size increased with the Al contents. The cells with bare, 0.5 and 1.0 at% Al-doped powders showed the initial discharge capacities of 182, 180 and $184mAhg^{-1}$ in a voltage range of $3.0\sim4.5V$ at 1C rate, and the capacity retentions of 81, 77 and 78% at the end of 30 cycles, respectively. But in the voltage range of $3.0\sim4.6V$, the Al-doping significantly enhanced the cycle stability. For example, the discharge capacity after 50 cycles was maintained to 70% in the 0.5 at% Al-doped sample compared to only 30% in no doped sample. The improvement of the cycle stability was thought to be due to $Mn^{3+}$ ion decrease as the Al doping from the XPS analysis results.

F-47 Rate of acute exacerbation in never smoker COPD versus smoker COPD

김선혜,( Sun Mi Choi ),( Jinwoo Lee ),( Young Sik Park ),( Chang-hoon Lee ),( Sang-min Lee ),( Jae-joon Yim ),( Young Whan Kim ),( Sung Koo Han ),( Chul-gyu Yoo ) 대한결핵 및 호흡기학회 2016 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.121 No.-

Aims: A substantial proportion of patients with chronic obstructive pulmonary disease(COPD) have never smoked. There is limited information about outcomes of the disease in this population. The aim of this study was to investigate the frequency and severity of acute exacerbation in never-smokers and in ever-smokers. Methods: This retrospective study included 420 COPD patients who visited the pulmonology outpatient clinic at Seoul national university hospital between June, 2012, and December, 2012. A diagnosis of COPD was based on the post-bronchodilator FEV1/FVC ratio, according to current GOLD guidelines. Never-smokers were defined as those with a lifetime exposure of less than 10 pack year. We assessed the frequency and severity of acute exacerbation during a median follow up of 38 months. Results: Among 420 COPD patients,154 never smokers and 266 ever smokers were enrolled.Total mean numbers of exacerbations per patient per year(1.70±3.22 vs 1.42±2.37; p 0.335), moderate exacerbations, treated with oral antibiotics and prednisolones, (1.04±2.20 vs 0.96±2.00; p 0.710), and severe exacerbations requiring hospitalizations and emergency department visit (0.53 ± 1.64 vs 0.36 ± 0.82; p 0.228) are no significant difference between never-smokers group and ever-smokers group. And the adjusted odds ratios for total number of exacerbations, moderate and severe exacerbations were 1.13(1.00-1.27), 0.80(0.43-1.46), and 0.876(0.47-1.72), respectively. Conclusions: Our findings suggest that the frequency and severity of exacerbations is not associated with smoking status.

유효하고 안전한 용량 결정에 위치를 이용한 비모수적 방법

김선혜,김동재,Kim, Sunhye,Kim, Dongjae 한국통계학회 2014 응용통계연구 Vol.27 No.7

일반적으로 약제 용량 결정 연구는 대조군과 여러 용량 수준을 비교하여 유효성과 안전성을 동시에 만족하는 약물의 치료 범위(therapeutic window)를 찾아내는 데에 관심이 있다. 이 논문에서는 안전성과 유효성을 동시에 만족하는 용량 결정을 위하여 선형 위치(linear placement)에 점수함수(score function)를 이용한 비모수적 검정법을 제안하였다. 또한 Monte Carlo 모의실험을 통하여 기존의 모수적 방법들과 검정력(power)과 FWE(family-wise error rate)를 비교하였다. Typical clinical dose development studies consist of the comparison of several doses of a drug with a placebo. The primary interest is to find therapeutic window that satisfying both efficacy and safety. In this paper, we propose nonparametric method for identifying effective and safe doses in linear placement using score function. The Monte Carlo simulation is adapted to estimate the power and the family-wise error rate(FWE) of proposed procedure are compared with previous methods.

아파트 간이화단의 녹지 조성을 위한 주민 의식조사

김선혜,Kim Sun-Hae 한국조경학회 2004 韓國造景學會誌 Vol.32 No.4

This study is about apartment greening to improve urban environment. To achieve this, questionnaires concerning the planter preferences were distributed. To improve perpendicular greening methods for apartments, MOCT (The Ministry of Construction and Transportation) reformed the law to obligate constructors to make apartment planters in June, 2000. But apartment residents take negative attitudes to making green space. It is difficult to manage the planters as well, so it is necessary that the point at making green spaces at apartments be scrutinized through questionnaires and an active method for making and managing the planter be made. The results show that apartment residents are reluctant to pay the expenses for planting and managing planters and have negative attitudes about plant purchases. If planting and managing of simplified planters are continually entrusted to residents, even vertical landscapes will be affected by illegal diversion and negligence as a result. Therefore, support from governments and local administrations are needed and legal obligation should be imposed on construction companies to install irrigation facilities.

염소계 유기화합물로 오염된 지하수의 반응성 투과 벽체 처리 효율에 대한 온도의 영향

김선혜 ( Sun Hye Kim ),김은지 ( Eun Zi Kim ),김동수 ( Dong Su Kim ) 한국물환경학회 2014 한국물환경학회지 Vol.30 No.2

The influence of temperature on the treatment efficiency of chlorinated organic substances contained in groundwater by permeable reactive barrier which is composed of Feo has been investigated by constructing the Pourbaix diagrams for Fe-H2O system at different temperatures based on thermodynamic estimation. In aerobic condition, the equilibrium potentials for Feo/Fe2+ and Fe2+/Fe3+ were observed to increase, therefore, the dechlorination reaction for organic pollutants by Feo was considered to decline with temperature due to the diminished oxidation of reactive barrier. The result for the variations of the ionization fraction of Fe2+ and Fe3+ ion in the pH range of 0 ~ 2.5 obtained by employing Visual MINTEQ program showed that the ionization fraction of Fe2+ increased with pH, however, that of Fe3+ decreased symmetrically and the extent of the variation of ionization fraction for both ions was raised as temperature rises. The equilibrium pH for Fe3+/Fe(OH)3 was examined to decrease with temperature so that the treatment efficiency of chlorinated organic substance was expected to decrease with temperature due to the enhanced formation of passivating film in aerobic condition. The change of the reactivity of a specific chemical species with temperature was defined quantitatively based on the area of its stable region in Pourbaix diagram and depending on this the reactivity of Fe3+ was shown to decrease with temperature, however, that of Fe(OH)3 was decreased monotonously as temperature is raised for Fe3+/Fe(OH)3 equilibrium system. In anaerobic condition, the equilibrium potential for Feo/Fe2+ was observed to rise and the equilibrium pH for Fe2+/Fe(OH)2 were examined to decrease as temperature increases, therefore, similar to that for aerobic condition the efficiency of the dechlorination reaction for organic substances was considered to be diminished when temperature rises because of the reduced oxidation of Feo and increased formation of Fe(OH)2 passivating film.

교통사고 환자 122례에 대한 한방치료 만족도 및 호전도 조사

김혜련(Hye Ryeon Kim),김선혜(Seon Hye Kim),이연선(Yeon Sun Lee),박서현(Seo Hyun Park),성원석(Won Suk Sung),조현석(Hyun Seok Cho),금동호(Dong Ho Keum),김갑성(Kap Sung Kim),김은정(Eun Jung Kim) 대한한의학회 2018 대한한의학회지 Vol.39 No.3