랫트의 생체내 카드뮴 단독투여 및 카드뮴과 셀레늄 병용투여에 따른 필수원소의 변화

김동현,변정식,조영채,이범식,김광환,김정윤 忠南大學校 環境問題硏究所 1995 環境硏究 Vol.13 No.-

This study was performed to find out the changes of essential elements as Cu, Fe, Zn, and Ca in blood, liver, kidney and testis of rats. The experimental rats were divided into 4 groups that were consisted of control group(groupⅠ), 3.0㎎Cd/kg group(groupⅡ), 3.0㎎Cd +1.0㎎Se/kg group(groupⅢ) and 3.0mgCd+2.5mgSe/kg group(groupⅣ). Each group was intraperitoneal injection with difference dose of cadmium and selenium such as 3.0mgCd/kg, 3.0mgCd+1.0mgSe/kg and 3.0mgCd+2.5mgSe/kg. Rats were killed at the time of 3 day and 28 day, and Cd, Se, Cu, Zn and Ca concentration in several organs were determined by Atomic Absorption Spectrophotometry and inductively Coupled Plasma. Cadmium content in blood, liver, kidney and testis were significantly increased in the Cd alone injection group than Cd mixed with selenium injection groups. But, copper content were not significantly differences in control and each experimental group. Iron content were significantly increased in the Cd alone injection group than others groups. Zinc and calcium content were significantly decreased in the Cd alone injection group than other groups. On the other hand the essential element content in Cd mixed with selenium injection group were almost equaled with those of control group than Cd alone injection group.

6-hydmxydopamine 파킨슨병 모델에서 Apomorphine의 투여에 따른 회전운동 변화의 시간적 추이

홍근식,김병곤,전범석,윤병우,이광우,노재규,이상복,명호진 대한신경과학회 1999 대한신경과학회지 Vol.17 No.1

힘과 운동 관련 선 그래프 해석과 이해에 관한 학생들의 오류 유형 검사 도구의 개발

문충식,김범기 한국교원대학교 과학교육연구소 1999 청람과학교육연구논총 Vol.9 No.1

선 그래프의 논리적이고 상징적인 특징 때문에 선 그래프는 과학, 특히, 물리에서 유용하고 중요한 수단으로 활용되고 있다. 그러나 학생들은 그래프를 해석하고 이해하는 데에 상당한 어려움이 존재한다. 본 연구는 힘과 운동 관련 선 그래프 해석과 이해에 관한 학생들의 어려움을 조사하기 위하여 면담 연구 등의 선행 연구에서 산발적으로 개발되어 사용되고 있는 문항을 바탕으로 신뢰롭고 타당한 검사 도구를 개발하는 것이다. 본 연구에서 개발된 힘과 운동 관련 선 그래프 해석과 이해에 관한 검사도구는 물리 교육과 과학 교육을 전공하는 대학원생들과의 세미나를 통하여 문항 목표와 문항 내용 그리고 내용 타당도를 검토하였으며, 3차에 걸친 예비 검사를 통하여 문항의 변별도와 신뢰도를 검토하였다. 검사 도구의 신뢰도(KR-20)는 0.92이고, 변별도 평균은 0.46이다. Line graphs are important in science, especially, in physics because of their logical and symbolic characteristics. However, students have difficulty interpreting and understanding line graphs. The aim of this study was to develop a reliable and valid instrument for identifying various problems with students' interpreting and understanding line graphs based on the items which had been used in previous studies, such as interviews and pencil and paper tests. The objective of the study and the contents of the items were identified through seminars attended by graduate students with science and physics education majors, Also, the reliability and the descriptive index of the items were tested three times through pilot tests. The reliability (KR-20) of this instrument was 0.92, and the average was 0.46.

數値解析을 利用한 粘性土地盤에서의 Retaining Wall의 擧動에 關한 硏究(Ⅰ)

劉範植,金仁培 안성산업대학교 1989 論文集 Vol.21 No.-

This paper deals with the behavior of retaining wall on soil condition and wall stiffness in clay soils. The results of study are as follows. 1. The passive earth pressure in low stiffness sheet pile is larger than it in high stiffness diaphram wall and elasto-plastic limit depth is deepened at the excavation depth of 5.5m above. 2. The deflection in deaphragm wall is more small than sheet pile and the more cohesion increased without relating wall stiffness, the more max, deflection is decreased, also, bending moment in deaphragm wall is lager than sheet pile. 3. When the retaining wall in clay in designed, there is need to design by introducing earth pressure modeling of elasto-plastic equilibrium state.

벽체의 뒷채움이 제한되어 있는 경우의 토압산정이론식

유범식,김훈제 안성산업대학교 1996 論文集 Vol.28 No.-

In case that the length of Backfill behind wall is confined, the active earth pressure acting wall will be reduced as compare with that calculated by conventional active earth pressure theories. Consequently, in this research , the theoritical formula of active earth pressure is proposed and conclusions are following. The angle of failure plane, 'α' of backfill soil is inclined to reduce as 'B/H' increase regardless of the angle of internal friction of backfill soil and earth pressure increase as the angle of internal friction reduce. The reduction effect of active earth pressure according to backfill length increase as 'B/H' more reduce than 'B/H=0.6'.

시멘트기초법에 의한 重金屬 固定效果에 關한 硏究

劉範植,金仁培 안성산업대학교 1994 論文集 Vol.26 No.-

This research evaluated Compressive Strength characteristic and Heavy Metal fixation by Cement-Based Solidification of waste. The Compressive Strength of solidified samples are related to Heavy Metal Elution and the more Compressive Strength is high, the more Heavy Metal is fixed. The Effect of Heavy Metal Fixation is high, specially at above 15% of stabilizer addition. The Compressive Strength is increased with curing times and stabilizer addition. Amount of Heavy Metal Elution by TCLP Method is higher than KSM Method because it is difference of experimental rule.

선 그래프 해석과 이해의 지각·인지 과정에 관한 모형 : 힘과 운동 관련 선 그래프를 중심으로

문충식,김범기 한국교원대학교 과학교육연구소 1998 청람과학교육연구논총 Vol.8 No.1

선그래프는 과학에서 정보를 전달하는 수단으로써 뿐만 아니라 실험의 결과를 해석하는 수단으로 유용하게 활용된다. 그러나 학생들은 그래프의 시각적이면서도 추상적인 특징 때문에 해석이나 이해에 상당한 어려움이 있다. 따라서 선그래프 이해의 지각ㆍ인지 과정을 분석하는 것이 매우 중요하다. 본 연구의 목적은 선그래프 해석과 이해에 관한 지각ㆍ인지 과정에서의 한 모형을 제시하는 것이다. 이 모형은 Pinker의 그래프 도식 이론과 Fisher의 정보 처리 이론에 기초를 두고 있으며, Lohse, Shah, Winn 등의 연구를 참고하여 제시하였다. 그리고 이 모형의 특징은 선그래프 문제를 해결하는 과정을 내용 독립적인 선그래프 해석과정과 내용 의존적인 선그래프 이해과정으로 나누었다. Line graphs are particularly effective in communicating relationships. They can convey vast amounts of information that cannot be communicated effectively by words or numbers alone. Thus, line graphs allow us to communicate scientific information and to see scientific data analyses. However, students are weak in their ability to comprehend line graphs because the features of line graphs are visual and abstract. McDermott et al. (1983) have shown that this is a problem even for many university students in the sciences. Then, it is very important to analyze the perceptual and cognitive processes in the comprehension of line graphs. The purpose of this study is to propose a model of line graph comprehension that includes perceptual and cognitive processes. This model is based on the graph schema theory of Pinker (1990) and the information processing theory of Fisher (1992). The major processes are the interpretation process and the comprehension process. In the interpretation process of line graphs, defined that the visual information of graphs is assimilated with the graph schema and is simultaneously accommodated to graph schema. The comprehension process of line graphs is one in which the result of the graph interpretation is assimilated with the existing conceptual schema on graphs and is simultaneously accommodated to the existing conceptual schema on graphs.

모 주물공장 근로자의 작업공정별 분진폭로량, 자각증상 및 건강진단판정 비교

이범식,조영채,변정식,김동현,원선혜,김정윤 忠南大學校 環境問題硏究所 1995 環境硏究 Vol.13 No.-

The relationship among dust exposure dose, special health diagnosis results and subjective symptom questionaire survey for 109 casting foundry workers supervised by a local laber office has been studied from august to october 1993. Subjective symptom, dust exposure dose and health examination evaluation of respective working processes have been analized and concluded as follows; 1. Metal fume concentration in melting process measured 3.21±1.46㎎/㎥ is under threshould limit value(TLV;5.0㎎/㎥), casting sand dust measured in molding and desanding process is 5.8 ±3.41㎎/㎥ and 9.69 ±2.64㎎/㎥ which is 3-5 times higher than TLV(2.0㎎/㎥), metal fume, welding fume and metal dust in finishing process measured 9.34 ±1.32, 13.73 ±16.97 and 10.17 ±3.50㎎/㎥ respectively, which are also 2-3 times higher than TLV(5.0㎎/㎥). 2. The complain rate subjective symptoms appeal evaluated for finishing process are 35.9%, 46.2%, 27.2% and 42.2% for eye smptoms, respiractory, skin, general symptom respectively and the rates above express the highest values and the complain rates for melting process are 24.4%, 37.5% and 35.7% for eye smptoms, respiratory and mental system respectively and for molding and desanding it is 24.3%. 3. Perceived occupational disease rate is found 0.9% with are out of 109 worker surveyed who have been exposed in metal fume of finishing process. 4. 33.0% of workers surved are found to require close examination, the worker of hepatopathy suspected are 21.4% which is the highest and 3.7% for circulatory disturbance suspected. 5. The statistically significant variables in general chracteristics that affect health examination evaluation are smoking(P<0.001), respirator put-on (P<0.05) and working career(P<0.05). 6. Cough(P<0.001), "headache"(P<0.05) and "easily skin exchange by slight stimulation" (P<0.05) are statistically significant to the subjective symptom variables affect health examination evaluation.

Fe-Sn系 燒結合金의 諸性質에 미치는 Sn粉의 粒度 및 配合量의 影響

홍범식,김윤채 三陟大學校 1997 論文集 Vol.30 No.1

Effects of particle size and content of tin powder on the properties of iron-tin sintered alloy for porous bearing were investigated in comparison with those of iron powder compact. The results obtained are as follows; 1) The effect of particle size of tin powder : When the particle size becomes finer, the compact shrinks a little and pore-structure becomes finer and then, the strength increases considerably. 2) The effect of tin powder content : When content of tin powder increases, the compact expands a little and also the pore-structure grows a little. But the strength decreases especially with increasing of the tin content above 1.5wt&. Therefore, it is desirable that the particle size is -350mesh and the content is about 1.0wt%.

경사하중이 작용하는 연약지반의 압밀침하 산정에 관한 연구

박춘식,장정욱,김범수 국립7개대학공동논문집간행위원회 2004 공업기술연구 Vol.4 No.-

This study determined consolidation settlement in soft ground with the tilted load by means of Terzaghi's one-dimensional consolidation theory and FEM. It was also compared with field measured value. The conclusions are summarized in the following. ⅰ) The consolidation settlement from Terzaghi's one-dimensional consolidation theory differ considerably from the measured value, but showed almost similar to that from FEM. ⅱ) Terzaghi's one-dimensional consolidation theory showed variable consolidation settlement according to methods to obtain △P. ⅲ) Consolidation settlement determined by FEM turned out to better evaluate the field settlement than Terzaghi's one-dimensional consolidation theory.