濟州島 植物群落의 生態學的 硏究 : 진달래 群落을 中心으로 The Communities of Rhododendeum mucronulatum

車鍾煥,金喆洙 동국대학교 농림과학연구소 1969 農林科學 論文集 Vol.3 No.-

This study is a series of plant ecological research of the Quelpart Island This experiment is concerned with an investigation of ground vegetation of Rhododendeum mucronulatum communities and analysis of soil properties located in the southern and northern parts of Hanla Mountain during the period from 1968 to 1969. 1. The number of species and the order of the dominant species which have appeared in each area near Yong Jin Kak, the northern part of Mt. Hanla are found as follow; ◁표 삽입▷(원문을 참조하세요) 2. The plants appeared among the Rhododendeum mucronulatum communities in the southern part of Mt. Hanla are found to be 29 species. The order of percentage of frequency are as follows : Agrimonia eupatoria, Carex aphanolepis, Carex siderosticta, Cirsium xanthocanthum, Rhododendeum mucronulatum, Duchesnea indica, etc. 3. Rhododendeum mucronulatum shows the high frequency in the A and B areas, Cirsium xanthocanthum and Carex siderosticta appear the highest in the C and D areas. 4. The species appeared in Rhododendeum mucronulatum communities are shown as follows : Cirsium xanthocanthum, Carex aphanolepis, Carex siderosticta, Smilax nipponica and Duchesnea indica having the highest frequency. 5. Although the same Rhododendeum mucronulatum community, Frequency Index Community Coefficient (F. I. C. C.) were different according to the directions, for example F. I. C. C. shown at the three parts of north Yong Jin Kak was high, while F. I. C. C. between the southern and the northern parts were low. 6. The differences of mineral contents of surface soils in the above states four places could be seen as follows : Total nitrogen, available phosphorus, exchangeable calcium, cation exchange capacity, organic matter and water content etc. 7. In the depth of 30 ㎝ of soil, the significant differences of soil properties have apparently been observed among total nitrogen, available phosphorus, organic matter and water contents etc. 8. The prominent differences of soil properties were seen in the available phosphorus, organic matter, and water content etc. in the depth of 60㎝ from soil surface. 9. The soil properties of B and C in each area have shown relatively high soil fertility. 10. The differences of soil properties in each soil horizon have been observed in total nitrogen, available phosphorus, exchangeable potassium and organic matter, and the more the depth increased, the lower value could be seen. 11. The correlation among the soil properties has been observed between organic matter and total nitrogen; organic matter and cation exchange capacity; exchangeable K and total nitrogen; exchangeable K and available phosphorus.

가공송전선로의 고장점 추정에 관한 알고리즘

申明澈,金喆煥 成均館大學校 科學技術硏究所 1985 論文集 Vol.36 No.1

As power systems expand and mature, the need for reliable and accurate fault location techniques grows imperative. Determination of the fault location means determining the distance between the location of the protection device and the location of the transmission line in which the fault has just appeared. For this purpose voltage and current are measured at the location of the protective device and the short circuit impedance can be determined. In this paper, the Algorithm to determine rapidly and accurately where faults have occured on a transmission line has been presented. Also, the Newton-Raphson method is used solving the nonlinear Algebraic Equation, and sufficient accuracy by applying to the KEPCO practical power system was obtained within seven iteration. Therefore, this study is expected that it is contributed to improve the reliability of power supplying, searching for the fault location rapidly and exactly, in power system fault.

확률ㆍ통계영역을 중심으로 한 고교 수학 Ⅰ 교과서의 비교

김철환,박동준 釜慶大學校 1999 釜慶大學校 論文集 Vol.4 No.1

This paper considers the contents of current mathematics I textbooks in high schools. The contents of the textbooks are reviewed with related to education objects. In particular, probability and atatistics chapters re examined based on the definition and explanation for curriculum proposed by The Education Ministry. The textbooks analyzed are the current five mathematics I textbooks of high schools under the sixth educational procedures. The chapters of textbooks are specifically analyzed with respect to array, order, organization, development, terminalogy, symbol, historical mathematician, assignment of problems and chapter summary focused on probability and statistics chapters.

單相變壓器 過渡勵磁電流의 調波分析

金喆煥,左宗根 제주대학교 1991 논문집 Vol.33 No.-

實測데이터 만으로 構成된 變壓器 等價回路와 鐵心의 磁化慝性을 曲線部分을 指數函數로 直線部分은 1次函數로 表現한 모델에서 印加電壓의 位相變化에 따른 過渡勵磁電流를 계산하여 각 cycle의 高調波를 FFT에 의해 分析하였다. 이 電流에 包含된 高調波成分을 각 cycle별로 高調波電流/過渡勵磁電流尖頭値에 대한 變化를 分析하였고 푸리에係數의 變化도 檢討하였다. This paper describes a method of analyzing harmonics of the transient magnetizing inrush currents in a single phase transformer. An equivalent circuit representation of the transformer, including its magnetic saturation characteristics, is also described. The inrush current wavefroms, which are calculated from the volage equilibrium equation for various switching instants of applied voltage, are deliberately analyzed at each cycle using the fast Fourier transform.

Sparganum에 감염된 흰쥐의 혈액상에관한 연구

이철환 진주여자전문대학 1991 論文集 Vol.14 No.-

In order to investigate the blood compound variety of infected Rats with parasites, the present studies analysed a blood of Wistar imanichi albino Rats infected with Sparganum, and than the increase of globulin quantity and WBC number were investigated The result was as follows ; 1. Globulin quantity was higher increased infected rat than non-infected rat. Especially, this pattern was clearly showed in 40-50 days and 80-90 days after infection. 2. From 30 to 40 days after the infection, the Eosinophil leucocytes of rat were increased, but were not more increased from after 40 days. 3. The Lymphocytes of rats were increased with increasing days from 20 to 100days 4. The Basophil leucocytes and the Monocytes were no variance in the WBC number.

근육교정에 의한 일측성 구순열 교정술

김진환,박철규 大韓成形外科學會 1983 Archives of Plastic Surgery Vol.10 No.2

In the unilateral cleft lip, the orbicularis oris muscle has a abnormal position and orientation. The muscle fibers are parallel to the margins of the cleft and inserted to the columlla in normal side and alar base in cleft side. If the orciculars oris muscle is not rearranged to a normal horizontal position, the balanced symmetry of lip motion and natural full thickness contour cannot be achieved. We have described a muscle repair technique which gives emphasis on the anatomcal horizontal repositionig of the orbicularis oris muscle in case of unilateral cleft lip repair and presented the following results after performing 31 cases. 1. The muscle dissection obviously adds the extended surgical trauma to the lip tissue and makes an operative procedure more complicated, but the postoperative course is uneventful as compared with the non-muscle reconstruction method. 2. By overlapping the two muscle flaps the wide muscle contact and union provide sufficient strength for normal function and the overlapping muscle flaps swell up and simulate philtral ridge. 3. By the separated repair of the orbicularis oris marginalis muscle the lower portion of the lip has a smooth full thickness contour. 4. The deformities of the nasal floor and alar base seem to be improved simultaneously by muscle dissection and repair alone. 5. The muscle repair technique has more advantages in case of wide complete unilateral cleft lip with hypoplastic marginal portion. 6. After the muscle reconstruction the secondary deformities seem to need only minor touch for skin distortions.

輸出의 國民經濟에 있어서의 役割 : 輸出不振과 國民經濟

金哲煥 연세대학교 경영대학원 1980 經營論叢 Vol.14 No.1

우리나라 수은 취급업체의 작업공정 및 수은중독 위험도에 관한 조사연구

차철환,김광종,염용태 大韓産業醫學會 1992 대한직업환경의학회지 Vol.4 No.1

This research was composed of two main parts. Firstly, metal mercury concentration in air of the total 10 fluorescent lamp manufacturing industries, and in urine and in blood of the total of 815 workers, was measured and evaluated in accordance with some contributing variables. Secondly, in order to evaluate the effectiveness of environmental intervention of two industries among the above, differences in mercury concentration sampled before and after the interventions were evaluated. Samples included air samples of work environments and those of urine of workers in two industries. The results were as follows. 1. Among 196 air samples, 39.8% exceeded metal mercury TLV (Threshold Limit Value) of Korea, 0.05mg/m³, and average mercury concentrations by work site were 0.069±0.038mg/m³in exhaustion site the showing highest level, and it declined as the distance from exhaustion site increased. 2. Average mercury concentration in air of exhaustion site was the highest at floor level showing 0.078±0.036mg/m³and the concentration at the level of worker's breathing zone and vacuum exhaustion pump also exceeded the metal mercury TLV. 3. Mercury concentration in urine of 15 workers (1.9%) among 792 workers exceeded dignostic criteria level of 300 μg/l, and of 411 workers (51.9%) exceeded warning level of 50 μg/l. Average mercury concentration in urine of workers was the highest in workers of exhaustion site showing 140.4±88.2μg/l and it declined as the distance from the exhaustion site increased. 4. Among 263 workers, 5 workers (1.9%) showed higher lever of blood mercury concentration than 20μg/l which was said to be dignostic criteria level in Korea, and 100 workers (38.0%) showed higher than 35μg/dl of warning level. 5. Among correlation coefficients between urinary mercury concentration and some contributing variables, the highest was 0.74 which related with the numbers of lamp destroyed per month, and 0.67 with the amount of mercury consumed per lamp, 0.63 with the amount of mercury treated by person in order. 6. Average mercury concentrations in air before the intervention were the level over the TLV, but they decreased after finishing the intervention reaching below the TLV level, showing effectiveness rate of intervention to be 57.3%. Average concentration in urine of workers also decreased after the intervention was half of it.

납, 수은 및 유기용제 폭로근로자들의 조기 신장 손상 지표인 요중 N-Acetyl-β-Glucosaminidase activity에 관한 조사연구

차철환,김광종,이은일 大韓産業醫學會 1993 대한직업환경의학회지 Vol.5 No.1

The urinary N-Acetyl-β-Glucosaminidase activity test has been recommended as sensitive method to detect early renal dysfunction by many toxic chemicals. To catch the high reference value of urinary N-Acetyl-β-Glucosaminidase activity in Korean, the total of 108 reference workers exposed only to noise were surveyed. And N-Acetyl-β-Glucosaminidase activities in 42 mercury workers at a fluorescent lamp manufacturing factory and 50 reference workers were measured to detect early renal dysfunction of mercury workers. The total of 27 mercury workers were followed 1 year to examine change of the N-Acetyl-β-Glucosaminidase activities according to the change of urinary mercury level. It was also examined to the N-Acetyl-β-Glucosaminidase activities of 8 lead exposed workers and 44 carbon disulfide exposed workers. It was examined to the correlation coefficients between the N-Acetyl-β-Glucosaminidase activities and total protein, β-1-microglobulin, β-2-microglobulin in 24 hour urine in 42 carbon disulfide exposed workers and 14 medical students as refernce group. And the correlation coeffecients between the N-Acetyl-β-Glucosaminidase activities in 24 hour urines and in spot urines were measured in 12 lead exposed workers and 43 mercury exposed workers. The results were as follows; 1. The high reference value of urinary N-Acetyl-β-Glucosaminidase activities in Korean was 180 nanomole methylumbellyferon/mg creatine of urine. 2. The correlation coefficients of N-Acetyl-β-Glucosaminidase activities and microalbumin, α-1-microglobulin, β-2-microglobulin in 24 hour urine were about 0.5 respectively. 3. The values of N-Acetyl-β-Glucosaminidase activities of spot urines in mercury exposed workers were statistically significant higher than those in reference group. and about 76.5% of workers of whom the urinary mercury level decreased after 1 year follow-up, also decreased the values of N-Acetyl-β-Glucosaminudase activities of spot urines. 4. There was no significant correlation between the N-Acetyl-β-Glucosaminidase activity of spot urines and blood lead level in lead exposed workers. But a half of workers have increased N-Acetyl-β-Glucosaminidase activities above the reference level. 5. The values of N-Acetyl-β-Glucosaminidase activities of spot urines in carbon disulfide exposed workers were statistically significantly higher than those in reference group. And for workers exposed to carbon disulfide and having retinopathy, the meanvalues of the N-Acetyl-β-Glucosaminidase activities were significantly higher, as compared to those having normal retina. 6. the correlation coefficients of N-Acetyl-β-Glucosaminidase activities between the values of 24 hour urines and those of spot urine were 0.76 in carbon disulfide exposed workers, 0.5 in lead exposed workers, 0.4 in mercury exposed workers, respectively. Among the correlation coefficients between the values of first morning urine samples and those of 24 hour urine samples were highest.

職業病鑑定

車喆煥 大韓法醫學會 1990 대한법의학회지 Vol.14 No.1

Korea has achieved rapid industrialization and economic development through the export drive policy since 1960. But these developments gave rise to serious occupational disease, pollution and other health problems. Because occupational disease originate from occupation and work environment unlike common diseases, the society has felt a great interest in occupational disease. In 1988, the number of cases of occupational disease in Korea was 8,919 among the 54.,000 cases of workers physical examination, and detection rate was 1.64%. Workers physical examination system is enforced, under the requirements of Occupational Safety and Health Law. For the judgement of disease due to occupational hazard, it is necessary to consider below items. 1) work character and working hours 2) working environment (threshold limit value of hazard substance) and health effect of hazard substance 3) specific clinical symptoms 4) incubation period 5) past history 6) differential diagnosis from other non-occupational cause 7) detection of other patient having similar symptoms 8) measurement of hazard substance and metabolite in blood and urine