수학적 재능에 대한 Krutetskii의 연구 분석

김성현,한인기,Kim, Sung-Hyun,Han, In-Ki 영남수학회 2011 East Asian mathematical journal Vol.27 No.4

In this study we study Krutetskii and Krutetskii's monograph 'The Psychology of Mathematical Abilities in Schoolchidren' which is published in Russia(in Russian) and USA(in English). We describe Krutetskii's biography briefly, which was not published in Korea. We analyze the methods, procedures, and results which are presented in the Krutetskii' work, and systemize these. Our study will give a overview of Krutetskii' viewpoint about mathematical abilities.

기천(氣喘)에 대(對)한 문헌적(文獻的) 고찰(考察)

김성현,Kim, Sung-Hyun 대한한방내과학회 1992 大韓韓方內科學會誌 Vol.13 No.2

This study has been carried out to investigate the cause, symptom and treatment of Gi-Chun (氣喘) by referring to 32 literatures. The results were obtained as follows; 1. The factor causing Gi-Chun (氣喘) is almost damage of feeling (七情損傷). 2. The symptom of Gi-Chun (氣喘) is as follows. agony, breathing urgent, cold hand and feet, body tired, low appetite 3. The treatment of Gi-Chun (氣喘) is as follows. Sunpaeganggi(宣肺降氣), Jihaepyungchun(止咳平喘), gudam(去痰) 4. The drugs(herb) of Gi-Chun (氣喘) is as follows. Samatang(四磨湯), Sachiltang(四七湯), Sojaganggitang(蘇子降氣湯), Gilgyungjigaktang(桔梗枳殼湯), Gamisachiltang(加味四七湯), Gamisoyosan(加味逍遙散).

키토산 분자량에 따른 Rhodamine 6G-Sodium Dodecyl Sulfate계의 응집효과에 관한 연구

김성현,나재운,오정선,송기동,Kim, Sung Hyun,Nah, Jae Woon,Oh, Jeong Sun,Song, Ki Dong 대한화학회 1998 대한화학회지 Vol.42 No.6

Chitin was extracted from crab shell of Portuns triberculatus and deacethylated to yield chitosan with various molecular weights. The absorption and the fluorescence spectra of Rhodamine 6G(Rh 6G)-sodium dodecyl sulfate(SDS) and Rh 6G-chitosan systems were obtained. From the spectra, we observed that the absorption and the fluorescence intensity of Rh 6G-SDS system decreased when S/D(the concentration of SDS to that of Rh 6G ratio) was below or at 32, while they increased when S/D was above 32. From the suspended solid(SS) removal rate and the transmittance of Rh 6G-SDS-chitosan system, we found that when S/D ratio was 32 its flocculating behaviour was much stronger than Rh 6G-SDS system. As the concentration and the molecular weight of chitosan increased, we also found that S/D range was extended from 32 to 100. With increasing the molecular weight of chitosan, the SS removal rate increased around pH 2~9 but decreased remarkably at pH>12. 산업폐기물인 꽃게의 껍질로부터 chitin을 탈아세틸화시켜 분자량이 서로 다른 chitosan을 제조하였다. Rhodamine 6G(Rh 6G)-sodium dodecyl sulfate(SDS)계 및 Rh 6G-chitosan계들의 흡수 및 형과 spectra를 조사하였고, chitosan의 분자량 및 pH에 따른 Rh 6G-SDS-chitosan계의 응집효과에 대해 조사하였다. Rh 6G-SDS계의 흡광도나 형광세기는 S/D(SDS 농도/Rh 6G 농도)=32 이하에서 감소하다가 그 이상에서 다시 증가하였다. 부유물질(SS) 제거율이나 투광도로부터 S/D=32에서 chitosan을 첨가한 Rh 6G-SDS-chitosan계의 응집 성능이 Rh 6G-SDS계에 비해 훨씬 우수함을 알 수 있었다. 그리고 chitosan의 농도나 분자량이 크면 클수록, S/D 첨가 범위는 32에서 100까지 확대되는 것을 알 수 있었다. 부유물질의 제거율은 chitosan의 분자량이 클수록 pH 2∼9에서 우수한 성능을 가지는 반면, pH 12 이상에서 부유물질의 제거율은 현저히 저하되는 것을 알 수 있었다.

소나무(Pinus densiflora) 묘목의 생장에 미치는 납과 CO₂의 영향

김성현,홍선화,강호정,류희욱,이상돈,조경숙,이인숙,Kim, Sung-Hyun,Hong, Sun-Hwa,Kang, Ho-Jeong,Ryu, Hee-Wook,Lee, Sang-Don,Cho, Kyung-Suk,Lee, In-Sook 한국생태학회 2006 Journal of Ecology and Environment Vol.29 No.6

본 연구는 $CO_2$ 증가와 Pb 오염이 소나무 묘목에 미치는 영향에 대하여 조사하였다. 납 오염 토양(500 mg/kg-soil)과 비오염토양에 2년생 소나무를 식재한 후, $CO_2$ 농도를 380 PPM 혹은 760 ppm으로 조절한 배양기에서 3개월간 생육시킨 후, 소나무 묘목의 성장, 납 함량 변화 및 토양의 물리 화학적 변화를 조사하였다. 소나무의 생체량과 뿌리 길이는$CO_2$ 농도에 따라 유의적인 차이를 보이지 않았으나, 납에 의한 저해는 뚜렷이 나타났다. 납 오염 토양에서 토양중의 납 잔류랑은 $CO_2$ 농도에 영향을 받지 않았으나, 소나무 뿌리중의 축적량은 $CO_2$ 농도가 높으면 2배 정도 높았다. 이러한 결과는 $CO_2$ 농도 증가가 소나무 뿌리의 Pb 생물 이용성에 영향을 미치는 것을 시사한다. This work was investigated the effects of the elevated $CO_2$ and Pb contamination on the growth of Pinus densiflora. Two-years pine trees were planted in Pb-contaminated soils (500 mg/kg-soil) and uncontaminated soils, and cultivated for 3 months in the growth chamber where $CO_2$ concentration was controlled at 380 or 760 ppmv. The growth of P. densiflora were comparatively analyzed in 4 kinds of soil samples (CA : $CO_2$ 380 ppmv + Pb 0 mg/kg, CB : $CO_2$ 380 ppmv + Pb 500 mg/kg, EA : $CO_2$ 760 PPmv + Pb 0 mg/kg, EB : $CO_2$ 760 ppmv + Pb 500 mg/kg). It was measured the growth changes of the p. densiflora caused by $CO_2$ concentration and Pb contamination. The growth of P. densiflora was remarkably inhibited in the Pb-contaminated soil, although the biomass and the root elongations were not significantly affected by the elevated $CO_2$. These results suggested that the growth of p. densiflora was sensitively influenced by Pb contamination rather than $CO_2$ concentration. Compared to the initial soil, total Pb concentration in the soil samples was decreased at 760 ppmv $CO_2$ as well as at 380 ppmv $CO_2$ after 3 months. The accumulation of Pb in the roots at 760 ppmv $CO_2$ was two-fold of that at 380 ppmv $CO_2$, indicating that Pb bioavailability in the root of p. densiflora might be affected by the elevated $CO_2$.

순천만 갈대근권 토양으로부터 얻은 PAH 분해세균의 특성 분석

김성현,강성미,오계현,김승일,윤병준,강형일,Kim Sung-Hyun,Kang Sung-Mi,Oh Kye-Heon,Kim Seung-Il,Yoon Byoung-Jun,Kahng Hyung-Yeel 한국미생물학회 2005 미생물학회지 Vol.41 No.3

This study was accomplished in order to collect fundamental data on microbial roles in recycling process of reed rhizosphere. Sunchon bay, which is considered as one of the marsh and mud environments severely affected by human activities such agriculture and fisheries, was selected as a model place. In our initial efforts, two bacterial consortia were obtained by enrichment culture using PAH mixtures containing anthracene, naphthalene, phenanthrene and pyrene as the sources of carbon and energy, and four pure bacteria capable of rapid degradation of PAH were isolated from them. Four strains designated as SCB1, SCB2, SCB6, and SCB7 revealed by morphological, physiological and molecular analyses were identified as Burkholderia anthina, Alcaligenes sp., Achromobacter xylosoxidans., and Pseudomonas putida, respectively with over $99{\%}$ confidence. Notably, Burkholderia anthina SCB1 and Alcaligenes sp. SCB2 were found to utilize anthracene and pyrene more quickly than naphthalene and phenanthrene, whereas Achromobacter xylosoxidans SCB6 and Pseudomonas putida SCB7 exhibited similar growth and degradation patterns except for pyrene. These facts suggest that the rhizosphere microorganisms capable of PAH degradation might be used to clean up the contamination sites with polycyclic aromatic hydrocarbons. 본 연구는 농업과 어업, 그리고 생태체험과 같은 인간들의 활동으로 인하여 상당히 영향을 받는 갯벌환경 중의 하나인 순천만을 모델장소로 갈대의 환경정화 기능에 있어 근권에 분포하는 미생물의 역할에 대한 기초 자료를 얻고자 수행하였다. 우선, 순천만의 갈대근권 토양을 시료로하고 anthracene, naphthalene, phenanthrene, pyrene 등이 첨가된 다환성 방향족 화합물(polycyclic aromatic hydrocarbons; PAH)을 탄소원 및 에너지원으로 하는 농화 배양을 통하여 두 개의 consortium을 획득하였다. 두 consortium으로부터 순수 분리된 우수한 PAH분해능을 갖는 4개의 균주(SCB1, SCB2, SCB6,그리고 SCB7)를 형태 및 생리학적 특성과 16S rRNA유전자서열을 기초로 분석한 결과 각 균주는 $99{\%}$ 이상의 신뢰도로 Burkholderia sp., Aicaligenes sp., Achromobacter sp., and Pseudomonas sp.로 동정되었다. 주목할 만한 점은 Burkholderia sp. SCB1과 Alcaligenes sp. SCB2는 naphthalene이나 phenanthrene보다 훨씬 안정되어 있는 구조의 anthracene이나 pyrene에서 더 빠른 성장률과 기질 분해율을 나타내는 것으로 밝혀졌다. 반면,Achromobacter sp. SCB6와 Pseudomonas sp. SCB7은 pyrene을 제외한 다른 시험기질에 대하여 유사한 성장 및 분해패턴을 나타내었다. 이러한 결과는 주요한 염습지 식물중의 하나인 갈대의 근권에서 살아가는 이들 PAH 분해 균주들이 PAH와 같은 물질로 오염된 근권 환경의 정화작용에 중요한 역할을 할 수 있음을 제시해 주었다.

N과 AlN 시트에 다양한 기체(CO_x, NO_x, SO_x)의 흡착에 관한 이론 연구

김성현,김백진,신창호,김승준,Kim, Sung-Hyun,Kim, Baek-Jin,Shin, Chang-Ho,Kim, Seung-Joon 대한화학회 2017 대한화학회지 Vol.61 No.1

본 연구는 그래핀과 유사한 2차원 붕소-질소(BN)와 알루미늄-질소(AlN) 시트에 여러 대기 유해 가스($CO_x$, $NO_x$, $SO_x$)가 흡착될 때의 구조적 특징과 결합에너지를 밀도 범함수 이론(DFT)과 MP2 방법을 사용하여 연구하였다. 분자 구조는 $B3LYP/6-31G^{**}$와 $CAM-B3LYP/6-31G^{**}$이론 수준에서 최적화하고, 진동 주파수를 계산하여 열역학적으로 가장 안정한 분자 구조를 확인하였다. 결합에너지는 $MP2/6-31G^{**}$ 이론 수준에서 한 점(single point) 에너지를 계산하고, 영점 진동에너지(ZPVE)와 바탕집합 중첩에러(BSSE)를 모두 보정하였다. BN 시트에 가스의 흡착은 모두 물리흡착으로 예측되었으며, AlN 시트에 대한 가스 흡착은 $CO_x$나 $NO_x$에 대해서는 물리흡착이 그리고 $SO_x$에 대해서는 화학 흡착이 일어날 것으로 예측되었다. The adsorption of various atmospheric harmful gases ($CO_x$, $NO_x$, $SO_x$) on graphene-like boron nitride(BN) and aluminum nitride(AlN) sheets was theoretically investigated using density functional theory (DFT) and MP2 methods. The structures were fully optimized at the $B3LYP/6-31G^{**}$ and $CAM-B3LYP/6-31G^{**}$ levels of theory and confirmed to be a local minimum by the calculation of the harmonic vibrational frequencies. The MP2 single-point binding energies were computed at the $CAM-B3LYP/6-31G^{**}$ optimized geometries. Also the zero-point vibrational energy (ZPVE) and 50%-basis set superposition error (BSSE) corrections were included. The adsorptions of gases on the BN sheet were predicted to be a physisorption process and the adsorptions of gases on the AlN sheet were predicted to be a physisorption process for $CO_x$ and $NO_x$ but to be a chemisorption process for $SO_x$.

상폐(傷肺)에 의(依)한 비출혈(鼻出血)의 문헌적(文獻的) 고찰(考察)

김성현,Kim, Sung-Hyun 대한한방내과학회 1991 大韓韓方內科學會誌 Vol.12 No.1

It has been known that the nosebleeding is a king hemorrhage occured to be damaged yang-rak (陽略) & lung. the results obtained were as follows; 1. The cause of nosebleeding were divided internal external, these were lung-heat(肺實熱), wind-heat(風熱), dry-heat(煥熱), wind-cold(風寒), summer-heat(暑熱), and those were transporting of Liver-fire(肝火犯肺), Liver-kidney-fire(肝腎陰虛熱傷肺), Stomach-fire(胃火熾盛), Heart-fire(心火千肺). 2. The treatment of external ; Chungpaesulyul(淸肺泄熱), Yanghyuljihyul(凉血止血), Sanpungchungyul(散風淸熱), Jaeumchungjo(滋陰淸煥). 3. The treatment of internal ; Chungkansahwa(淸肝瀉火), Yanghuljihyul(凉血止血), Jayumganghwa(滋陰降火), Chunguysahwa(淸胃瀉火). The cause of nosebleeding was almost heat (fire), and the treatment were Sanpyo(散表) & Chungri(淸裏).

디지털 방사선 흉부영상의 영상개선과 임상평가

김성현,서태석,최보영,이형구,Kim, Sung-Hyun,Suh, Tae-Suk,Choe, Bo-Young,Lee, Hyoung-Koo 한국의학물리학회 2008 의학물리 Vol.19 No.3

본 연구의 목적은 디지털 방사선 흉부영상의 개선을 위한 영상처리방법을 제안하고 임상적 유용성을 평가하는 것이다. 흉부영상의 edge를 보존하면서 산란성 노이즈 제거를 위한 비선형의 반복 필터가 고안되었다. 영상의 다이나믹 레인지 (dynamic_range)의 조절이 이루어 졌으며, 해부학적 영역과 주변픽셀과의 호환성을 바탕으로 적응적 영상증강이 이루어졌다. 종격동 영역에서의 영상증강과 더불어, 폐 영역에서의 혈관조직, 기관지, 폐 조직 등이 적절하게 증강되었다. 3명의 판독의에 의한 임상평가가 이루어 졌으며, PA 영상에서는 11개, 그리고 Lateral 영상에서는 9개의 해부학적 영역이 면밀하게 관찰되었다. 각각 100장의 영상들이 ITU (International Telecommunication Union) recommendation 500에 따라 평가되어졌으며, 그 결과는 good과 adequate중간인 3.4의 평균치를 보였다. 이는 제안한 영상처리의 임상적 유용성이 최소한 양호함 이상의 가치가 있음을 의미한다. 유용한 해부학적 정보의 손실을 방지하기 위해, 영상표시장치와 인간의 인지계를 고려하면서 영상개선이 이루어졌다. 디지털 방사선기기의 등장으로 진단의 정확성을 향상시키기 위한 지속적인 영상 개선연구가 필요하다. The aim of this study is to suggest the method for image enhancement of digital chest radiograph and evaluate clinically the quality of the resultant image. A nonlinear iterative filter was developed in order to reduce quantum noise preserving edge. Dynamic range was adjusted and adaptive image enhancement was performed based on the property of anatomic region and the degree of compatibility with neighboring pixels. The lung fields were enhanced appropriately to visualize effectively vascular tissue, bronchus and lung tissue with the desired mediastinum enhancement. Clinic evaluation was performed by three radiologists with at least 8 years experience. The anatomic regions of 11 in PA and 9 in Lateral were observed carefully in each 100 radiographs according to ITU (International Telecommunication Union) recommendation 500 protocol. The result showed the mean 3.4 between good and adequate. This means that the clinical utility of the image quality is enough. In this study, image enhancement was carried out considering image display device and human perceptual system to prevent the loss of useful anatomic information. In order to increase the diagnostic accuracy in digital radiograph, the continuous study on image enhancement is needed.

치주치료 후 구강 내 Volatile Sulfur Compounds(VSC)의 변화

김성현,채경준,정의원,김창성,최성호,조규성,채중규,김종관,방은경,Kim, Sung-Hyun,Chae, Gyeong-Jun,Jung, Ui-Won,Kim, Chang-Sung,Choi, Seong-Ho,Cho, Kyoo-Sung,Chai, Jung-Kyu,Kim, Chong-Kwan,Bang, Eun-Gyeong 대한치주과학회 2006 Journal of Periodontal & Implant Science Vol.36 No.3

Oral malodor may cause a significant social or psychological handicap to those suffering from it. Oral malodor has been correlated with the concentration of volatile sulfur compounds (VSC) produced in the oral cavity. Specific bacteria identified in the production of VSC have been reported and many of these bacteria are commonly suspected periodontal pathogens. The aim of this study was to estimate the change of the VSC concentration after periodontal treatment, Twenty subjects with probing depth $(PD)\;{\geq}5mm$ (experimental group) and 20 subjects with PD<5mm (control group) participated. VSC concentration measurement was made with gas chromatography. VSC concentration was measured at pre-treatment, 2 weeks after scaling and 1 month after periodontal treatment(root planning and flap operation). Maximum probing depth and bleeding on probing(BOP) were also examed at pretreatment and 1 month after periodontal treatment, The conclusions were as follow: 1. In the experimental group VSC concentration and CH3SH/H2S ratio were higher than control group. (p<0.05) 2. Both VSC concentration and CH3SH/H2S ratio showed decrease after periodontal treatment, But only CH3SH/H2S ratio after 1 month periodontal treatment was statistically significantly different from pre-treatment. (p<0.05) 3. CH3SH/H2S ratio tended to be on increase according to maximum probing depth and bleeding on probing. Periodontal disease could be a factor that caused oral malodor and oral malodor could be decreased after periodontal treatment.

FR4 PCB면적과 Via-hole이 LED패키지에 미치는 열적 특성 분석

김성현,이세일,양종경,박대희,Kim, Sung-Hyun,Lee, Se-Il,Yang, Jong-Kyung,Park, Dae-Hee 한국전기전자재료학회 2011 전기전자재료학회논문지 Vol.24 No.3

In this study, the heat transfer capability have been improved by using via-holes in FR4 PCB, when the LED lighting is designed to solve the thermal problem. The thermal resistance and junction temperature were measured by changing the dimension of FR4 PCB and size of via hole. As a result, when the dimension was increased initially, the thermal resistance and junction temperature was decreased rapidly, the ones was stabilized after the dimension of 200 $[mm^2]$. Also, the light output was improved up to maximum 17% by formation of via-hole and expansion of dimension in FR4 PCB. Therefore, the thermal resistance and junction temperature could be improved by expansion of PCB dimension and configuration of via-hole ability.