이상설 : 한국 근대수학교육의 아버지

설한국,이상구,Seol, Han-Guk,Lee, Sang-Gu 한국수학사학회 2009 Journal for history of mathematics Vol.22 No.3

본 논문은 한국수학사에서 연구와 정리가 취약한 시기인 근대수학의 도입기를 조사하면서, 그 근대수학의 도입기에서 만나게 되는 인물인 이상설(李相卨)에 대한 조명을 시도한다. 시대적 상황이 모든 분야의 침체기를 가져온 구한말 이상설은 근대수학에서 당대를 대표하는 높은 학식을 쌓고 뛰어난 재능을 보여주었다. 그간 이상설에 대해 '근대수학교육의 아버지'라는 평가가 없지 않았음에도 불구하고 낯설게 느껴진다면, 그것은 그가 독립운동가로만 강하게 각인된 탓일 것이다. 하지만 그는 19세기말 조선 근대수학의 첫 번째 교과서 편저자이자 수학교사이기도 했음을 새겨둘 필요가 있다. 대유학자이면서도 선구적으로 외국어와 서양과학 특히 근대 서양수학을 이해한 면모는 한국이 배출한 천재 중 하나라는 평가가 결코 과장이 아님을 보여준다. 이에 본 논문에서는 한국 근대수학교육에 커다란 기여를 한 인물인 이상설의 교육과 학문 및 실천업적을 조명한다. 보재 이상설이 1886년경에 쓴 책 <수리>와 최초로 수학과 과학을 관립교육기관의 교육과정에 편성한 과정, 최초의 근대수학교과서로 여겨지는 <산술신서>의 발간, 민족교육기관인 '서전서숙'의 설립 및 운영을 포함한 보재의 업적을 한국수학사 관점에서 조명한다. 또한 <산술신서>의 목차와 구체적인 내용 및 1901년에 출간된 <신정산술>의 내용을 소개하고, 지금까지 부정확하게 알려진 <수리>와 <산술신서>에 관한 몇 가지 역사적 사실을 발굴하여 재조명한다. Most who have heard of Sang-Seol Lee know him for his contribution to the Korean independence movement nearly a hundred years ago. This paper, however, will discuss Lee's other great contribution to his country; that of being "The father of modern mathematical education in Korea". Lee passed the rigorous government officer examination with the highest honor and became a teacher for the royal prince. Later he became the president of Sunkyunkwan, a national institute of higher learning since 1398, and eventually a well-known university bearing the same name. Lee was also a highly regarded Confucian scholar and well versed in foreign languages. He wanted Korea to become a modern country and felt that the areas of science and engineering were studies that needed improving in order to achieve modernization. While researching Western textbooks on the subjects he realized that Western mathematics would be especially important for Korea. With that, it became his mission to integrate Western mathematics into the Korean educational system. This paper will explain the importance of Sang-Seol Lee's contributions to mathematic education in Korea and how it helped Korea become the modern nation it is today.

흰쥐 성장기간에 따른 Xylene의 독성에 관한 연구

이혜자,이상희,전태원,이상일,윤종국 대한의생명과학회 2000 Journal of biomedical laboratory sciences Vol.6 No.3

실험동물에 있어서 연령 차이에 따라서 xylene 독성이 어떠한 차이가 있는지를 검토하는 일환으로 5주령 및 12주령 흰쥐에 50% m-xylene을 체중 100 g 당 0.25 ml씩 1회 투여한 다음 24시간 후에 처치하여 다음과 같은 결과를 얻었다. Xylene 투여로 인한 요 중 methylhippuric acid 함량은 5주령군이 12주령군에 비해 현저하게 높게 나타났다. 그리고 간조직 중 cytochroms P-450 함량은 대조군에 있어서 5주령군이 12주령군 보다 약 50% 정도 낮게 나타났으나 xylene 투여로 인한 cytochrome P-450 함량 증가율은 12주령군 보다 5주령군에서 높게 나타났다. 간 alcohol dehydrogenase 활성치도 대조군에 있어서는 5주령군이 12주령 보다 약 35% 정도 낮게 나타났으나 xylene 투여로 인한 본 효소의 활성 증가율은 5주령군에서 오히려 높게 나타났다. 그러나 간 aldehyde dehydrogenase 활성치는 대조군 및 xylene 투여군 모두 5주령과 12주령간에 유의한 차이를 나타내지 않았다. 한편 xylene 투여시 체중 당 간무게, 간조직 malondialdehyde 함량 및 혈청 ALT 활성 변동을 통하여 간손상 정도를 상호 비교 관찰하였을 때, 12주령군이 5주령 실험동물 보다 간손상이 다소 심하게 나타남을 알 수가 있었다. 이상 실험결과는 연령에 따라 xylene에 의한 간손상의 차이는 이물질의 생체내 대사율이 달리 나타나기 때문일 것으로 생각된다. To evaluate an effect of aging on the xylene toxicity, 50% m-xylene in olive oil (0.25 ml/100 g body wt.) was administered to 5 week and 12 week-old rats one times intraperitoneally and sacrificed at 24 hrs afterwards. The increasing rate of urinary H-methylhippuric acid concentration was higher in 12 week-old rats than 5 week-old rats by the treatment of m-xylene. On the liver function findings, i.e., liver weight/body weight (%), serum levels of ALT activity and hepatic malondialdehyde content, 12 week-old rats showed more severe liver injury than 5 weeks those in xylene-treated rats. And the hepatic cytochrome P-450 contents was higher in 12 weeks rats than those of in 5 week-old rats, but the increasing rate of that was lower in 12 week-old rats. Hepatic alcohol dehydrogenase activity was also higher in 12 week-old rats than in 5 week-old rats whereas the increasing rate of that was higher in 5 week-old than those in 12 week-old rats by the xylene treatment. Furthermore, the hepatic aldehyde dehydrogenase activities were no differences between the 5 and 12 week-old rats both in the control and xylene-treated group, In conclusion, age may influences upon the hepatotoxicity with xylene and it may be responsible for xylene metabolism in rats.

Performance of electrochemical double layer capacitors using highly porous activated carbons prepared from beer lees

Sang Guk Lee,Hee Moon,Kwang Hyun Park,심왕근,M.S. balathanigaimani 한국공업화학회 2011 Journal of Industrial and Engineering Chemistry Vol.17 No.3

Beer lees precursor is chosen to prepare activated carbons having different physical and chemical properties. The beer lees-based activated carbons (BL-ACs) are characterized by N2 adsorption/desorption isotherms, adsorption energy distributions (AEDs), and X-ray photoelectric spectroscopy (XPS). Furthermore the electrochemical properties of the BL-ACs are assessed using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and constant current charge/discharge method. The maximum specific capacitance (about 188 F/g at discharge current of l mA/cm2) is obtained in 0.1 M H2SO4 electrolyte solution, which is a relatively low electrolyte concentration. The overall results suggest that the BL-ACs are good candidates for EDLC electrode materials.

야뇨증 환아들의 심리사회적 특성에 대한 다기관 연구 : 행동 및 정서 문제를 중심으로

조수철,김재원,신민섭,황준원,한상원,박관현,이상돈,김경도,김건석,서홍진,이유식,정재용,김영균,문두건,남궁미경,한창희,조원열,김영식,배기수,이종국,정우영,신의진 大韓神經精神醫學會 2005 신경정신의학 Vol.44 No.6

Objectives : The aim of this study was to examine the behavioral and emotional problems associated with nocturnal enuresis in Korean children. Methods : Three hundred eighteen children with nocturnal enuresis, together with their parents, completed the Child Behavior Checklist (CBCL), Disruptive Behavior Disorder Scale according to DSM-IV (DBDS), Children's Depression Inventory (CDI), State-Trait Anxiety Inventory for Children (STAIC), and Piers-Harris Children's Self-Concept Scale (PHCSC). Ninety-three normal students were selected as the control group. Results : Compared to the normal control group, the mean scores with regard to the withdrawn, social problems, attention problems, delinquent behavior, aggressive behavior, externalizing problems and total problems profiles were significantly higher in the nocturnal enuresis group according to the CBCL results. The nocturnal enuresis group also scored significantly higher in the ADHD and ODD profiles of the DBDS. The nocturnal enuresis group was more depressed and anxious than the control group according to the results of the CDI and STAI. The mean score of the PHCSC was significantly lower in the nocturnal enuresis group when compared to the normal control group. Conclusion : The results of this study suggest that children with nocturnal enuresis in Korea have clinically relevant behavioral and emotional problems. The findings support the link between nocturnal enuresis and psychopathology in Korean children.

종 분포 모형을 이용한 구상나무림의 지속 및 쇠퇴에 관한 연구 - 전라남도 광양시 백운산을 중심으로 -

조선희 ( Seon Hee Cho ),박종영 ( Jong Young Park ),박정호 ( Jeong Ho Park ),이양근 ( Yang Geun Lee ),문이만 ( Lee Man Mun ),강상호 ( Sang Ho Kang ),김광현 ( Gwang Hyun Kim ),윤종국 ( Jong Guk Yun ) 한국산림과학회 2015 한국산림과학회지 Vol.104 No.3

The present study investigated the habitats of Korean fir trees (Abies koreana E. H. Wilson) on Mt. Baekwun (Baekwun-san), determined the current distribution, quantified the contribution of biological and nonbiological environmental factors affecting the distribution, derived actual and potential habitats, presented a plan for the establishment of protected areas, applied RCP 8.5 climate change scenario to analyze the effects of climate change on the future distribution of Korean fir trees, and predicted future potential habitats. According to the results of the study, 3,325 Korean fir trees (DBH >= 2.5 cm) inhabited Mt. Baekwun, and their distribution area was approximately 150 ha. Populations of Korean fir trees were confirmed to exist at an altitude of 900 m above sea level and were distributed up to 1,200 m. Based on potential distribution, areas appropriate for habitation by Korean fir trees were analyzed to be 450 ha, three times the current distribution area, with a focus on Sang Peak (Sang-bong), Eokbul Peak (Eokbul-bong), Ddari Peak (Ddari-bong), and Dosol Peak (Dosol-bong). The forest stands near Sang Peak, the main peak, were evaluated as those with the most appropriate potential for the habitation of Korean fir trees, and populations of the trees tended to prefer the northern slope rather than the southern slope. When climate change scenario RCP 8.5 was applied and future potential distribution was analyzed, the habitats were expected to decrease in area to 20 ha by 2050, with a focus on Sang Peak, and areas appropriate for habitation were predicted not to exist by 2080. Judging from such results, as global warming accelerates, the habitats of Korean fir trees are clearly expected to move from lowlands to highlands.

Bromobenzene의 투여 횟수에 따른 간독성의 차이

이상희,전태원,윤종국 대한의생명과학회 2000 Journal of biomedical laboratory sciences Vol.6 No.1

실험동물에 있어서 간조직의 손상 정도에 미치는 xenobiotics의 투여기간에 의한 영향을 검토할 목적으로 hepatotoxin의 일종인 bromobenzene의 투여 횟수에 의한 간손상 정도와 이의 기전을 구명 한 결과는 다음과 같다. 횐쥐에 1일 간격으로 bromobenzene (400 mg/kg)을 복강으로 1회, 3회 및 6회 투여 한 실험군을 대상으로 하여 실시한 실험에서 혈청 alanine aminotransferase (ALT)의 확성 및 체중 당 간 무게는 bromobenzene을 1회 투여 한 1일째에는 대조군과 별다른 변동을 볼 수 없었으나 3회 투여 한 3일째에는 유의하게 증가되었으며, 이후 6일째 6회 투여한 실험군에서는 체중 당 간 무게 및 혈청 ALT활성이 3일째 보다 현저히 감소되어 오히려 대조군과 유사하였다. 이와 같이 투여 횟수의 증가에 따른 간손상의 정도가 투여 횟수와 비례하지 않은 것이 어떠한 기전에 의해서 나타나는지를 구명하기 위해 bromobenzene 대사에 관여 하는 간조직 중 aniline hydroxylase 및 glutathione S-transferase 활성과 glutathione (GSH) 함량을 측정한 결과, 이들 대사효소 및 GSH이용률이 bromobenzene 6회 투여 군에서 1회 및 3회 투여군보다 높게 나타났다. 이상 실험 결과를 종합해 볼 때 어떤 독성물질이 생체에 계속 폭로 시 어느 시점에서 중독현상이 경감되는 것은 이 독성물질의 대사율을 증가시켜 해독하려는 생리적응현상이 일어 날 수 있다는 가설을 제시 할 수 있다. A Study on the Effect of Injection Frequency on the Liver Damage in Rats To investigate the effect of injection frequency of bromobenzene on the liver damage, bromobenzene (400 mg/kg, i.p.) was given daily to rats for six days. All experimental animals were sacrificed at 24 hours after the last injection. Morphological changes of the liver were observed under a light microscopic examination. Functional changes of the liver were evaluated by the measurement of alanine aminotransferase activity. To clarify the cause of discrepancy in liver damage, hepatic glutathione (GSH) content, glutathione S-transferase (GSI) and aniline hydroxylase (AH) activities were determined. In the experiments of daily bromobenzene treatments, the sacrificed animals at six day (6 time-injected animals) showed slighter liver damage than those sacrificed at 3 day (3 time-injected ones), based on the liver morphological or functional findings; the decreasing ratio of GSH content and increasing ratio of liver GST and AH activities in the 6 time-injected group were higher than those in the 3 time-injected one.

초음파법을 이용한 Cr-Mo강 고온배관재료의 크리프손상 평가

이상국 한국비파괴검사학회 2000 한국비파괴검사학회지 Vol.20 No.1

화력발전소 보일러 고온배관인 주증기관, 헤드 및 증기드럼 등의 설비들은 장시간동안 고온고압의 가혹한 조건으로 운전됨에 따라 크리프손상에 의해 열화되고 있다. 이들 설비의 크리프손상측정에 적용되는 종래의 비파괴기법인 레프리카법, 전기저항법 및 경도법 등은 복잡한 측정절차 및 접근성, 검사결과의 신뢰도 및 측정정도 등 여러가지면에서 단점이 많다. 따라서 본 논문에서는 화력발전소 주요 고온배관에서 발생되는 경년열화인 크리프손상에 대한 초음파 측정연구를 수행한 결과로서, 고온배관재료인 Cr-Mo강의 프리프 인공열화재를 대상으로 이들에 대한 크리프손상 상태별 초음파 음속(sound velocity) 및 감쇠(attenuation)의 초음파 신호특성을 평가하였다. Boiler high-temperature pipelines such as main steam pipe, header and steam drum in fossil power plants are degraded by creep damage due to severe operating conditions such as high temperature and high pressure for an extended period time, Conventional measurement techniques(replica method, electric resistance method, and hardness test method) for measuring creep damage have such disadvantages as complex preparation and measurement procedures, too many control parameters, And also these techniques have low practicality and applied only to component surfaces with good accessibility. In this paper, artificial creep degradation test and ultrasonic measurement for their creep degraded specimens(Cr-Mo alloy steels) were carried out for the purpose of evaluation for creep damage. Absolute measuring method of quantitative ultrasonic measurement for material degradation was established, and long term creep degradation tests using life prediction formula were carried out. As a result of ultrasonic tests for crept specimens, we conformed that both the sound velocity decreased and attenuation coefficient linearly increased in proportion to the increase of creep life fraction(φc).

음향방출법에 의한 탄소 섬유 복합재료의 인장 및 파괴

이상국,김옥균,남기우,오세규 韓國非破壞檢査學會 1995 한국비파괴검사학회지 Vol.15 No.1

본 연구는 [0°.90°]₂s와 [0°₂/90°₂]s의 2종류 탄소섬유복합재료에 대한 인장 및 파괴인성 시험시의 파괴거동과 음향방출 특성을 해석하고 성형시의 성형압력과 인장강도 및 파괴인성 간의 상관성을 알아내기 위하여 수행되었다. AE신호는 음향방출장비를 이용하여 성형과정, 인장 및 파괴인성 시험중에 각각 검출하였다. 인장강도는 성형가압 단계수가 적을수록, 그리고 [0°/90°]₂s 시험편 쪽이 [0°₂/90°₂]s 시험편보다 높은 강도를 나타내었다. 파괴인성은 동일한 온도영역에서 거의 같은 값을 나타내나 시험온도가 높아질수록 점차 낮아짐을 알 수 있었다. 한편 인장 및 파괴인성 시험시의 파괴거동과 AE신호간의 상관성을 조사하기 위하여 AE데이터의 AE변수들에 대한 후 신호처리(post processing)와 광학현미경 및 주사형 전자현미경 관찰이 각각 수행되었다. The study was carried out to analyze the fracture behavior and the acoustic emission(AE) characteristics and to find the relationship among tensile strength, fracture toughness and cure pressure in cure process of the carbon fiber reinforced composites of two types, [0°/90°]₂s and [0°₂/90°₂]s. AE signals were detected during the curing process, tensile tests and fracture toughness tests by acoustic emission(AE) measurements, respectively. Tensile strengths showed that the less cure pressurizing steps and the side of [0°/90°]₂s specimens had the higher strengths than those of the others. Fracture toughness by change of test temperature showed nearly same values in the same temperature region, but the higher test temperature had the lower fracture toughness values. In order to examine the relationship between fracture behavior of CFRP in tensile and fracture toughness tests and AE signals, the post processing for AE parameters of AE data and the observations of microscope and SEMA have been carried out respectively.

교각형상에 따른 국부세굴에 관한 실험적 연구

이성대,이현국,신현길,이승훈 한라대학교 2007 論文集 Vol.10 No.-

For geotechnical and economical reasons, various bridge piers have become more and more popular in bridge design. This type of pier can significantly reduce construction costs, compared to spread footer structures when sediment scour is a consideration. However, the scour mechanisms for piles are much more complex, and design of local scour depths more difficult to predict. In this Experiments of local scour around the downward tapering oblong pier with the geometrically nonlinear structurea and a series circular piers are carried out under steady clear water scour conditions. The paper presents the following research results: The scour at a series circular piers is different from that around a single pile, depending on the pile spacing. The interference effect diminishes for pile spacing L_(d)/D=3.5, depending on the pile group arrangement.

수처리 디지털 계장시스템의 성능 향상을 위한 고성능 스텝 모터 개발에 관한 연구

이상호,이진,김현국 삼척대학교 산업과학기술연구소 2001 産業科學技術硏究論文集 Vol.6 No.1

In this paper, we have developed the new dovetail tooth(DVT) shape in order to improve the torque and accuracy of variable reluctance stepping motor(VSM). Also it was analyzed by Finite Element Method(FEM) and Virtual Work Method. As a result of this paper, it was confirmed that the static torque characteristics of VSM was improved considerably.