불교와 철학 ( 속 ) - 만동종천 (萬東鍾天) ( 조선불교총보 (朝鮮佛敎叢報) 제 12 호 , 1918 년 )

이종천 삼십본산연합사무소 1918 朝鮮佛敎叢報 Vol.12 No.-

최적설계 및 다중공정을 적용한 일체형 접이식 복합재료 날개 개발 연구

이종천 항공우주시스템공학회 2018 항공우주시스템공학회지 Vol.12 No.3

This research was carried out to develop an integrated folding wing made from carbon composite materials. Design requirements were reviewed and composite wing sizing was conducted using design optimization with commercial software. Three composite manufacturing processes including hot-press, pultrusion, and autoclave were evaluated and the most suitable processes for the integrated wing fabrication were selected, with consideration given to performance and cost. The determined manufacturing process was verified by two design development tests for selecting the design concept. Stiffness and strength of the composite wing were estimated through structural analyses. The test loads were calculated and static tests about design limit load and design ultimate load were performed using both wings. As a result, the evaluation criterions of the tests were satisfied and structural safety was verified through the series of structural analyses and testing. 탄소섬유 복합재료를 적용하는 일체형 접이식 날개 개발에 대한 연구를 수행하였다. 설계 요구조건을검토하고 상용 소프트웨어를 적용한 최적설계기법을 통해 복합재료 날개 설계를 실시하였다. 복합재료제조공정인 핫프레스, 펄트루전, 오토클레이브를 평가하고 성능과 비용을 고려하여 일체형 날개제작에가장 적합한 다중공정을 결정하였다. 설계개념 확정을 위해 두 차례의 설계개발시험으로 제작공정을 검증하고 구조해석을 통해 복합재료 날개의 강성과 강도를 예측하였다. 시험하중을 먼저 산출하고 양쪽날개를 대상으로 설계제한하중과 설계극한하중에 대한 정하중 구조시험을 수행하였다. 그 결과, 시험의각 평가기준을 만족하였으며 일련의 구조해석과 시험을 통해 구조안전성을 검증하였다.

염화나트륨 함유 구중청량제의 치면세균막 및 구취 제거 효능평가

이종천,조자원,유현준,김찬호,최병기 대한턱관절교합학회 2022 구강회복응용과학지 Vol.38 No.1

Purpose: The purpose of this study was to evaluate the effects of mouthwash containing sodium chloride on dental plaque, gingival inflammation index, and bad breath through clinical trials. Materials and Methods: This trial was designed as 12 weeks and subjects were instructed to put an appropriate amount of the provided standard detergent on a toothbrush and brush their teeth 3 times a day. They were instructed to gargle a mouthwash provided to each group after brushiung. Efficacy was evaluated by performing gingival and periodontal-related index tests, dental plaque changes, and bad breath tests a total of 5 times. All data were statistically analyzed using 2-sample t-test, paired t-test to compare between groups at 95% significance level using IBM SPSS Statistics 24.0. Results: As a result of the PMA index measurement, the gingivitis improvement effect rate of the experimental group compared to the control group was 107.63% after 8 weeks and 73.08% after 12 weeks. As a result of the PHP index measurement, the plaque improvement effect rate of the experimental group compared to the control group was 79.37% after 8 weeks and 74.06% after 12 weeks. As a result of measuring volatile sulfur compounds using Oral Chroma, the effectiveness of improvement in bad breath in the experimental group was 65.06% after 8 weeks and 99.33% after 12 weeks, compared to the control group. Conclusion: As a result of this study, it was confirmed that effective gingivitis alleviation, plaque removal effect and bad breath removal effect can be expected when a mouthwash containing sodium chloride, green tea extract, and sodium monofluorophosphate is used. (J Dent Rehabil Appl Sci 2022;38(1):1-8)

선진국 환경시료은행의 특성 분석을 통한 국가환경시료은행의 발전방안

이종천,김명진,Lee, Jong-Chun,Kim, Myung-Jin 대한자원환경지질학회 2012 자원환경지질 Vol.45 No.2

The ESBs (Environmental Specimen Banks) have monitoring functions for the contemporary environmental qualities and also offer the future generation tangible information on the past environment by preserving the specimens. This entails the sampling of the representative specimen for each distinctive ecosystem, which is performed under a strict and stipulated procedure and a condition that does not allow any change in the component so that a retrospective analysis can be readily done even in the distant future. It has been more than 30 years that some developing countries started collecting a broad spectrum of specimens to vindicate the effectiveness of an environmental policy and to monitor the long-term variations of background concentrations of environmental pollutants. Though being late, the National Institute of Environmental Research (NIER), Korea, has successfully launched the National Environmental Specimen Bank (NESB) in 2009 equipped with its state-of-the-art automated cryogenic tanks. Since then, the researchers at the NESB have been doing their best to excel the existing ESBs around the world by learning and improving the expertise. To do so, they conducted a pilot study for developing and testing their own Standard Operating Procedure (SOP) based on the analysis of the examples of the other ESBs. The problems from the pilot study had been reviewed to improve the SOP to meet the requirements for an ESB, that is to say, preserving representative environmental specimens in cryogenic condition and enhancing the analytical method. Furthermore, they also need to prepare themselves to address the future challenges by providing some additional functions, which makes it distinguishable from the other ESBs. If successful, this will be a step further to be recognized as a full-fledged member of the ESB society of the world.

오염토양의 효율적 조사기법과 측정불확도의 평가방법

이종천 대한자원환경지질학회 2004 자원환경지질 Vol.37 No.1

The concectration and distribution of contaminants obtained from a contaminated land investigation or an environmental geochemistry survey constitutes the basis of a decision-making process on environmental policies or of scientific researches. As the quality of data determines the reliability of the result, the investigation plan should be adjusted according to the purpose of the investigation. In general, the effort to improve the data quality had been focused mainly on the QA/QC procedures in laboratories. The rapid progress of analytical instrument has also contributed toward improving the analytical precision to a sacrificable degree. Nevertheless, in many cases, it is not the analytical precision that needs improvement for the better precision of overall measurement process: it is rather during the sampling process in the field that is responsible for the poor precision. To assess the data quality on a measured value, ISO recommends to provide information on "measurement uncertainty" along with the measured value. The measurement uncertainty in an environmental measurement context can be explained as the statistical number that expresses the degree of the uncertainty stemming from the sampling and analytical procedures. There is a cost involved in order to improve the precision of sampling and analytical methods so as to decrease the degree of measurement uncertainty. The economical point of compromise in an investigation planning can be achieved when the allowable degree of uncertainty has been set before-hand. The investigation can then be planned accordingly not to exceed the uncertainty limit. Furthermore, if the measurement uncertainty estimated from the preliminary investigation can be separated into sampling and analytical uncertainties, it can be used as a criterion where the resources for the investigation should be allotted cost-effectively to reinforce the weakest link of the whole investigation process. This paper aims to present a method of estimating the level of measurement uncertainty of a measured contamination concentration at a site used as an example and to show how the estimated uncertainty can be applied to serve the particular purpose of an investigation.

제3기층 기저역암에 협재되는 벤토나이트의 광물학, 지화학적 연구 및 층서적 적용

이종천,이규호,문희수 대한자원환경지질학회 2001 자원환경지질 Vol.34 No.1

Bentonite layers are intercalated within the basal conglomerates in the Tertiary sedimentary basins of Kampo, Janggi and Pohang, southeastern Korea. Eighteen samples of the bentonites went through X-ray diffraction, scanning electron microscopy, heavy mineral analyses, chemical analyses and oxygen, hydrogen stable isotope analyses to define the mineralogical characters of the bentonites. Heavy minerals such as zircons, apatites, amphiboles and biotites separated from bentonites show clean and euhedral surfaces, which are the characteristic features of volcanic origin. But biotites from the Chunbook Conglomerate are found as altered and heavily broken flakes which implies longer transportation of these bentonites. $TiO_{2}/Al_{2}O_{3} ratios of <2 $\mu$m particle fractions (the Chunbook Conglomerate 0.031; Janggi 0.029; Kampo 0.025) suggest that those are originated from volcanic tuffs. That is, the higher the value is, the more mafic in chemical compositions of the original tuffs. Authigenic montmorillonite and zeolite minerals were observed by SEM, which indicates diagenesis origin of bentonites. But the samples from the Chunbook Conglomerate showed only chaotically packed clay flakes in the matrix of sands or conglomerates, which implies detrital influence, not authigenic origin. The structural formulae of montmorillonite from these basins reflects their environment of formation. Fe (Ⅵ) can show the redox condition of its past environment and much lower $Fe^{2+}(Ⅵ)/Fe^{3+}(Ⅵ)$ ratios in montmorillonite of the Chunbook Conglomerate imply the greater oxidizing influence. Calculated burial depths from oxygen stable isotope data of the samples from the Chunbook Conglomerate generally fall to the range of 929~963 m whereas the real burial depth of this area is only 530~580 m. This could be explained as the bentonites of the Chunbook conglomerate had not been formed in situ. Discriminant analyses with the data from chemical analyses and structural formulae of montmorillonites show that bentonites from three different basins could definitely be distinguished with each other. This result arises from the different chemical compositions of original volcanic ashes and the difference of sedimentary environments.

종교론 (宗敎論)

이종천 통도사 내 취산보림사 1921 취산보림 Vol.1 No.-

땅두릅의 체세포배로부터 2차배 발생과 식물체 재생에 미치는 싸이토카이닌의 영향

이종천,소웅영 한국식물생명공학회 2000 식물생명공학회지 Vol.27 No.2

땅두릅 미성숙 화기절편을 이용하여 1 mg/L 2,4-D의 고체배지에서 배발생 캘러스를 유도하였고 동일조건의 액체배지에서 증식시켰다. 배발생 세포를 270$\mu\textrm{m}$의 걸름체로 거른 다음 배발생 세포는 싸이토카이닌이 포함된 MS 액체배지에서 2주 동안 배양하였고 그후 생장조절물질이 없는 MS 액체배지에서 5주간 배양하여 1차 체세포배가 유도되었다. 이들중 어뢰형과 자엽형 시기의 배를 생장조절물질이 없는 MS고체 배지에 치상하였을 때 캘러스의 형성 없이 2차배가 직접 유도되었다. 2차배를 유도할 때 2mg/L kinetin에서 얻어진 1차 배에서 가장 높은 빈도의 2차배가 발생되었다. 식물체 재생은 1 mg/L kinetin 혹은 1 mg/L zeatin을 처리하여 얻어진 1차 자엽형배로부터 유도된 2차 자엽형배를 생장조절물질이 없는 MS 고체배지에 치상하였을 때 높게 나타났다 (각각 25.4%, 28.6%). 2차배로부터의 3차배 발생과 식물체 재생과의 상관 관계를 볼 때 식물체의 재생에 있어서 3차배의 배발생은 저해적인 영향을 주었다. Embryogenic suspension cultures were initiated using embryogenic callus from immature inflorescence explants (Aralia cordata Thunb.) cultured on solid MS medium containing 1 mg/L 2,4-D for 8 weeks and then the embryogenic callus was proliferated in liquid MS medium containing 1 mg/L 2,4-D. After sieving the suspensions (pore size 270$\mu$m), embryogenic cells were cultured in liquid MS medium with cytokinins (kinetin, BA, zeatin) for two weeks. When the embryogenic cells were transferred to liquid MS basal medium, primary somatic embryos were developed after 5 weeks of culture. Secondary embryos were developed directly from the primary torpedo and cotyledonary embryos cultured in solid MS basal medium. Frequency of secondary embryogenesis was higher on medium containing 2 mg/L kinetin than the other cytokinins. Plant regeneration was highly recorded by placing secondary cotyledonary embryos induced from primary cotyledonary embryos in MS medium containing 2 mg/L kinetin or 2 mg/L zeatin (25.4% and 28.6%, respectively). The plant regeneration from secordary embryos was prohibited by tertiary embryogenesis.

두 변수 탄성지반으로 지지된 원호형 등단면 띠기초의 자유진동

이종천 한국구조물진단유지관리공학회 2009 한국구조물진단유지관리공학회 논문집 Vol.13 No.1

이 논문은 직시각형 단면을 갖는 원호형 등단면 띠기초의 자유진동에 관한 연구이다. 띠기초를 지지하는 지반을 두 변수 탄성지반으로 모형화하였다. 두 변수 탄성지반으로 지지된 원호형 띠기초의 휨-비틀림 자유진동을 지배하는 미분방정식을 유도하고 이를 수치해석하여 고유진동수 및 진동형을 산정하였다. 띠기초의 경계조건은 자유-자유로 하여 최저저차 4개의 고유진동수를 산정하였다. 수치해석의 결과로, 중심각, 깊이비, 접촉비, 탄성계수비, 지반변수 등 5개의 변수가 고유진동수에 미치는 영향을 보고하였다. 변위 및 합응력의 진동형을 그림으로 나타내었다. 실험을 통하여 이 연구의 결과를 검증하였다 This paper deals with the free vibrations of circular strip foundations which have uniform solid rectangular cross-section. The ground which supports circular strips was modeled as the two parameter elastic foundation. Differential equations governing the flexural-torsional free vibrations of circular strips supported by such foundation were derived, and solved numerically for obtaining the natural frequencies and mode shapes. Boundary condition of free-free ends was considered for numerical examples. Four lowest natural frequencies according to the variations of five system parameters i.e. subtended angle, depth ratio, contact ratio, elasticity ratio and soil parameter are reported in the non-dimensional forms. Also, typical mode shapes of both deformations and stress resultants are presented in the figures. Experiment was conducted for validating the theory developed in this study.

기독교 (基督敎)와 불교 (佛敎)의 입각지 (立脚地) ( 조선불교총보 (朝鮮佛敎叢報) 제 14 호 , 1919 년 )

이종천 삼십본산연합사무소 1919 朝鮮佛敎叢報 Vol.14 No.-