In this study, the odor compounds emitted from the field workplaces at the Pohang steel complex were measured using analytical instruments and the olfactory method. In addition, the reduction of odor emissions by pyroligneous liquid was evaluated. The odor samples were obtained from slag pots and dry pits, which refrigerate hot slag, and the target compounds were hydrogen sulfide (H₂S) and ammonia (NH₃). The levels of odor emissions varied with meteorological and operating conditions, but emissions from dry pits were always much higher than those from slag pots. As the concentration of pyroligneous liquid increased, the concentrations of H₂S and the ratios of dilution decreased. Together with this result and the guideline of odor emissions, the increase of pyroligneous liquid (more than 2.5 times) in cooling water was suggested to reduce odor emissions. Actually, the reduced levels of H₂S at the slag pot and the dry pit were observed (70 and 94%, respectively) after the increased amount of pyroligneous liquid. However, in order to determine the optimal amount of pyroligneous liquid for the economical and efficient removal of odor emissions, the system of cooling water has to be improved and more samples are required for a comprehensive analysis.

The main objective of the statistical analysis about industrial accidents is to find out what is the dangerous factor in its own industrial field so that it is possible to prevent or decrease the number of the possible accidents by educating those who work in the fields for safety tools. However, so far, there is no technique of quantitative evaluation on danger. Almost all previous researches as to industrial accidents have only relied on the frequency analysis such as the analysis of the constituent ratio on accidents. As an application of data mining technique, this paper presents analysis on the efficiency of the CHAID algorithm to classify types of industrial accidents data and thereby identifies potential weak points in accident risk grouping.

산업재해 통계분석의 커다란 목적은 각 산업별로 주 위험요인을 도출하고 이에 따른 안전교육의 실시 또는 안전장치 등을 보완함으로써 산업재해를 줄이거나 예방하는데 있다고 볼 수 있다. 그러나 일반 제조업이나 건설업 등에서는 아직까지도 정량적 위험성 평가 기법이 개발되어 있지 않은 실정이다. 따라서 효율적인 위험성 평가 기법의 개발이 필요하다. 본 연구에서는 데이터마이닝 기법을 이용한 산업재해 예방을 위한 최적 알고리즘 선정 방법을 제시한다.

Many researches have been focused on the analysis of industry disasters in order to reduce them. As a similar endeavor, this paper provides a propensity analysis of injured people from various industries using classification and regression tree(CART), a data mining algorithm. The sample for this work was chosen from 25,157data related to various industries during one year ( 2003.2~2004.1 ) at Kangwon-Do in Korea. For the purpose of this paper, eight independent variables (injured date, injured time, injured month, type of Injured person, continuous service period, sex, company size, age)are taken from injured person group. According to the analysis result, it is found that five out of the eight factors that are predicted as significant have salient effects. Factors of season, time/hour, day of the week, or month which disasters happened do not show any significant effect. This paper provides common features of injured people. The provided analysis result will be helpful as a starting point for root cause analysis and reduction of industry disasters and also for development of a guideline of safety management.

생체 폐를 대신해서 임시적으로 제공하는 폐 보조 장치(LAD)의 사용은 기계 환기술의 단순화와 체외순환 막형 인공폐의 기능을 결합하여 급성호흡부전 환자에 적합하다. 본 연구에서의 주 관심은 폐 보조 장치에서의 막 진동 효율에 있었으며 정량적인 실험 측정은 혈액 용혈에 대한 막 진동 의존을 확인하기 위하여 실행하였다. 또, 혈액 용혈은 막 진동이 이루어질 때 한계 용혈의 가진 주파수 대에서 결정하였다. 최대 기체 전달율을 보이는 675의 중공사 막으로 이루어져 있는 유형 5의 가진 주파수에서 최대 진폭의 발생 및 중공사에 진동의 전달에 의해 최대 산소 전달율이 일어났다. 이 주파수가 혈류량에 가동 가능했던 제 2 형태의 공진 주파수가 되어 높은 각 혈류량 비에서 25±5 헤르쯔까지 가진이 되었으며, 혈액 용혈은 25±5 헤르쯔의 가진 주파수에서 상대적으로 낮았다. 따라서 우리는 이 폐 보조 장치의 한계 용혈 주파수가 25±5 헤르쯔인 것으로 결정했다.

고도화된 산업의 발달로 인하여 많은 업종들이 생겨나게 되었고, 그로 인해 크고 작은 사고들이 발생하게 되었다. 사고의 발생은 부상, 사망과 질병 등의 재해자들을 발생시키고, 사고로 인한 재해자의 수는 한 사업장에서도 여러 건씩 발생한다. 이러한 재해자의 공통된 특성 요소와 성향을 분석할 수 있다면, 1%의 재해자라도 더 줄일 수 있으리라 사료된다. 본 논문에서는 업종별 그룹을 통해 재해자들의 특성화 분석을 위하여 총 25,157개의 데이터를 바탕으로 데이터 Mining 기법중의 하나인 Classification and Regression Tree(CART)를 이용하여 분석을 하였다. 종속변수인 10개의 주요 업종을 중심으로 재해자들이 어떠한 성향을 나타내고 있는지 알아보고자 독립변수인 재해자 구분, 재해시간, 근속기간, 성별, 회사 규모와 연령 등 8개 항목을 채택하여 재해자 위험 그룹을 분석하고 그 결과를 제시한다.

해양 구조물은 일반 구조물과는 달리 구조물 속으로 염화물이 침투하기 때문에 시간이 지나면서 빠르게 부식을 하게 되고, 부식이 진행됨에 따라 구조물의 붕괴를 야기 시킨다. 그러므로 염화물의 침투 정도와 부식의 진행 상태를 예측할 수 있다면 사고 예방은 물론, 친환경적 해양 구조물이 될 수 있으리라 사료된다. 본 논문에서는 이러한 해양 구조물의 염화물 침투를 예측하고, 부식으로 인한 구조물 붕괴 및 사고를 예방하고자 Sample Design을 통하여 서로 조건이 다른 시험체를 해수에 잠식시키고, 일정기간이 지난 후 Data를 수집하였다. 수집된 Data는 정규분포(Normal Distribution)를 따르지 않는다는 사실을 알게 되었고, 수집된 데이터를 예측 시스템 구축에 활용하기 위한 준비 단계로서 데이터 선정의 타당성을 검토하기 위해 수명분포분석(Lifetime Distribution Analysis)을 실시한 뒤 그 결과를 제시하였다.

It is not difficult to see the road repairing. There are many and various machines which crush road surface. The efficiency and power of the machine depend on crushing head-shape, crushing interval, crushing load, crushing stress, machine's dropping height and roller's kind. The objective of this study is to select the optimal model among ten models of crushing machine with constraints such as crushing depth, variation, and crushed particle size. And then this paper provides the valid theoretical base on selected model. The data for this study are chosen from the site of construction in Kangnung during three months (2004. 6. 1~2004. 8. 31). The provided methodology in this paper will be fruitful not only for the selection of crushing machine but also for the aspects of construction period, cost, work efficacy according to the condition from the various sites of construction.

Pod-edible bean or snap bean is a fairly new crop to domestic farmers but the national demand is steadily increasing in recent years along with the development of western food business and change in dietary patterns. At the same time, much efforts are being made to export it to foreign country, mainly to Japan. The amount of seeds introduced from outside is also continuously increasing along with the enlargement of area planted for the crop. Hybridization breeding for the crop has already been started to supply the cheaper and better seeds which will reduce the seed costs and foster the higher income to the farmers. In this experiment, several technologies related with the production of quality seeds are preliminary investigated. Some of the results obtained are summarized as follows; 1. Highly significant interaction was recognized between planting dates and no. of pods per plant and no. of branches but no interaction between planting dates and plant height and no. of nodes on main stem. Days to maturity was proportionally reduced to later planting dates. 2. Rate of viviparous pods and seeds was gradually increased in later planting dates but rate of germination was increased in earlier planting dates with lower germination rate in white seed coat grains than in colored seed ones. 3. Seed yield was higher in the earlier planting dates with a great deal of varietal difference. Early to mid April was considered to he the optimum planting dates for snap bean in Kyungbuk area. High correlation was recognized between seed yield and no. of pods per plant, no. of seeds per plant, and 100 seed weight. 4. Days to flowering was three and seven days longer in Cheongsong, high mountainous area than in Kunwi, somewhat prairie lowland. One hundred seed weight was also higher in Cheongsong than in Kunwi. Rate of viviparous grains, pods, and decayed seeds was higher in Cheongsong but, at the same time, the rate of germination and seed yield was also higher in Cheongsong. 5. One hundred seed weight of KLG5007 increased continuously up to 35days after flowering and decreased thereafter but that of KLG50027 increased to 40days after flowering and slowly reduced thereafter. The content of crude oil reached to maximum at 40 days after flowering and reduced thereafter. The rate of germination in Gangnangkong 1 was the highest, 89.3%, at 35 days after flowering and reduced thereafter while that in KLG50027 reached to maximum, 70.7%. at 40days after flowering and reduced thereafter. Thus, the optimum harvesting time for snap bean was considered to be 35~40days after flowering. 6. The snap bean pods at yellow bean stage easily became viviparous ones under saturated moisture conditions for 24 hours at . Therefore, it is recommended to harvest pods somewhat earlier than yellow-bean stage and let them do post maturing, especially when it is to be rained.

It is not difficult to see the road repairing. There are many and various machines that can crush road surface. The efficiency and power of the machine depend on crushing head-shape, crushing interval, crushing load, crushing stress, machine's dropping height and roller's kind. The objective of this study is to select the optimal model among ten models of crushing machine with constraints such as crushing depth, variation, and crushed particle size. The data for this study are chosen from the site of construction in Kangnung during three months (2004. 6. 1 ~ 2004. 8. 31). The provided methodology in this paper will be fruitful not only for the selection of crushing machine but also for the aspects of construction period, cost, work efficacy according to the condition from the various sites of construction.

High-speed machining is one of the most effective technologies to improve productivity. Because of the high speed and high feed rate, high-speed machining can give great advantages for the machining of dies and molds. High speed machine tool makers try to

Epithelial-mesenchymal interaction is well known to have an importance during the organ development as well as cell growth and differentiation. However, in vitro experimental model is not well developed to reproduce in vivo cellular micro-environment which provide a epithelial-mesenchymal interaction. The aims of this study were to develop and evaluate the in vitro experimental model that maintains epithelial-mesenchymal interaction by organotypic raft culture, and to characterize biologic properties of three-dimensionally reconstituted human normal oral kertinocyte(NHOK) and immortalized human oral keratinocytes(IHOK) by histological and immunohistochemical analysis. The results were as follows; 1. Best condition of three dimensionally reconstituted IHOK & HaCaT cells are 14 days air-exposure cultivation, 3 days of submerged state, and dermal equivalent consisting type I collagen and IGF cells. 2. In comparison to IHOK, there was better preservation of the overall epidermal strucutures in oral cracioma cells (HN30) & HaCaT cells by organotypic cultures. But orgnaotypic co-culture of the normal keratinocyte showed the thinnest epithelial layer formation. 3. PCNA was detected primarily in the basal layer of normal mucosa and NHOK, whereas was shown throught the epithellium except surface layer of IHOK cells, and it's expression was similar to that of CIS of biopsied patient's tissue 4. Involucrin is expressed in the upper layer of oral mucosa and NHOK raft, but staining for involucrin was induced in the IHOK rafts indicating differentiation is incomplete, and the staining pattern in the IHOK raft was not uniform. 5. Normal oral keratinocyte raft showed weak immunostaining for p53, and p53 expression of IHOK raft increased rahter than in NHOK. In organotypic cultures of normal cells and IHOK, p53 expression was restricted to the proliferative part of epithelium. This is consistent with expression pattern in biopsy specimens of the normal and CIS tissue. 6. In artifically reconstructed NHOK, the pattern of keratin staining showed both similarity and differences from that of intact normal mucosa. An obvious difference was increased expression of CK10 & CK19, and decreased expression of CK6 in a reconstructed NHOK rather than in normal mucosa, and similar expression was in CK4 and CK16. 7. CK19 & CK16 were strongly positive in HPV immortlaized keratinocyte rafts rahter than in NHOK, an indicator of premalignant or malignant changes, while CK10 & CK6 were decreased, and organotypic cultures of IHOK express was similar keratin expression as epithelial dysplasia or CIS tissue. These results suggest that three-dimensional organotypic co-culture of normal oral & immortalized keratinocytes with dermal equivalent consisting type I collagen and fibroblasts results in similar morphologic and immunohistochemical characteristics to in vivo patient specimens. Thus this organotypic system can be used for studing mechanism of epitehlial-mesenchymal interaction in particular regulating epidermal diffenentiation and morphogenes

In case of rectangular latticed pattern which shearing rigidity is very small, it has a concern to drop Buckling-strength considerably by external force. So, by means of system to increase buckling-strength, there is a method of construction that lattice of dome is reinforced by braced member. In a case like this, shearing rigidity of braced member increase buckling-strength of the whole of structure and can be designed economically from the viewpoint of practice. Therefore, this paper is aimed at investigating how much does rigidity of braced member united with latticed member bearing principal stress of dome increase buckling-strength of the whole of structure. the subject of study is rectangular latticed domes that are a set of 2-way lattice dome which grid is simple and number of member gathering at junction is small. Analysis method is based on FEM dealing with the geometrically nonlinear deflection problems.

곡면가공에서 5축 가공은 복잡한 형상의 공작물에 대한 가공의 필요성이 증대되면서 3축가공보다 자유곡면 가공을 위한 시도와 연구가 활발히 이루어지고 있으나 가공 시 충돌과 간섭의 문제를 해결해야하는 어려움으로 공구경로 생성에 많은 문제점을 내포하고 있다. 이러한 문제를 해결하고자 최근에는 다양한 5축 CAD/CAM Software가 개발 되었고 이를 활용하는 사례가 늘어나고 있다. 본 논문에서는 자유곡면으로 이루어진 대표적인 형상인 Impeller의 복잡한 형상을 CAD Software를 이용하여 모델링 하였고, CAM Software로 공구 경로를 생성 및 검증하였으며 5축 가공기로 직접 가공하였다.

현실적으로 최근 공작기계의 고속화가 급속히 진전되고 있는 것이 세계적인 기술 추세이다. 이와 맞물려 고속공작기계 내지는 고속가공시스템 표준 평가방법의 정립이 필요하다. 이에 본 논문은 고속가공기의 특성이나 성능평가 방법을 위해, 가공방향 조도상차이, 표면조도, X,Y축 이송에 의한 직각도 및 Z축 떨림, 상한돌기, 직경감소와 미소지정, 열변형랑, 가공시간등의 테스트항목을 선정하여 육안검사시편을 개발 및 가공함으로써, 고속가공기의 특징을 분석하여 최적의 기계성능을 활용할 수 있게 하고자 한다.

We used three-dimensional Matrigel culture system to examine the morphognesis of normal and malignant salivary glands cell in vitro including acinar cells(AC), myoepithelial cell(MC), salivary gland adenocarcinoma cells(SGT), mucoepidermoid carcinoma cells(MEC), and immortalized human salivary gland cells(HSG). For this purpose, normal and salivary gland tumor cells cultured in 3-D Matrigel, and characterized histologically and immunohistochemically, compared with same cells grown on monolayer culture and patient tissue from biopsy. 1. In three-dimensional Matrigel culture, HSG cells form acinar structure, SGT cells shows duct like structure, and other AC, MC and MEC cells dont' form any structure , and their morphology was different from that of monolayer cells. 2. Matrigel involved cell proliferation at a similar pattern to cells on plastic monolayer cell cultures, and monolayer cell revealed higher cell viability than that of Matrigel cultured cells. 3. All salivary glands cells on Matrigel or monolayer showed strong PCNA expression, and there is no expression difference in these cells. But some cells including myoepithelial cells in normal and salivary gland tumor tissue showing PCNA lavelling, so there is PCNA expression difference among normal and tumor tissue cells. 4. Actin expression was noted in AC cells on Matrigel, were rare expressed in the other cells except in MEC cells, and was present in myoepithelial cell and ductal cells of normal gland tissue. There is actin expression difference between tissue and cultured cells . 5. S-100 immunoreaction was moderateively positive in MC cells of monolayer culture, myoepithelial cells of normal tissue and pleomorphic adenoma, all cancer cells of mucoepidermoid carcinoma tissue, but significantly decreased in all salivary cells on Matrigel. 6. TGase 2 expression was prominent in MC cells of monolayer and Matrigel cultured, in myoepithelial cells of normal gland and pleomorphic adenoma, epidermoid cells of mucoepidermopid carcioma, and strong reaction in MEC and AC cells of monolayer and Matrigel cultured. 7. Expression of CK in monolayer culture showed strong reaction to CK6 in all sailvary gland cells, and mild reaction to CK10 and CK16 for all salivary cells, CK16 and CK19 expression in monolayer culture was similar to that of Matrigel culture. 8. CK6 and CK10 expression was strongest in AC and MC cells on Matrigel, and CK 4 was negative reaction in AC, SGT, MEC cells, strong reaction in MC cells but mild in SGT cells on Matrigel. Expression of CK was rare in HSG cells compared with other salivary gland cells, CK16 was prominent in SGT cells, CK10 and CK16 showed strongest expression in MEC cells of Matrigel. 9. Monolayer culture of HSG cell shwoing strong reaction to CK6, moderate to CK19 and mild to the others CK, but 3D cultured HSG cells reveal mild expression to CK16, and rare to others CK, intercallated duct in normal gland tissue showing strong to CK19, and mild to the others Ck, so there are CK expression difference in tissue, monolayer and 3-D cultured cells. 10. Monolayer culture of MEC cells represent strong reaction to CK6, mild to other CK, 3-D cells showing increased CK expression including CK6, epidermoid cells and intermediate cells in mucoepidermoid carcinoma tissue reveal positive to CK6 and CK16, mucous cell positive to CK10 and CK19, so Matrigel showed similar CK pattern compared to mucoepidermoid carcinoma tissue rather than monolThese data indicate that the interaction of salivary gland cells with basement membrane is an important factor in salivary gland development and cytodifferentiation, so this model system will be useful to study acinar or ductal differentiation in vitro.ayer cultred.

무발정 증상을 보이는 젖소 65두를 대상으로 몇 가지 호르몬 처리기법을 사용하여 소의 번식효율 향상시키고자 본 실험을 수행하였다. Group 1. Ovsynch program (GnRH-PGF a /PGF a/GnRH), Group 2. Two plus Two program (GnRH-PGF a /PGF a/GnRH), Group 3. progesterone implant (CIDR)-GnRH/PGF a/PGF a/GnRH과 Group 4. (Folli

고속 가공은 고속가공기마다 자체의 기계적 특성이나 강성이 모두 다르므로 공작기계를 생산하는 회사 자체에서 자사의 장비가 가장 좋은 특성을 낼 수 있는 조건을 알아내기 위해서 기계의 여러 가지 항목을 확인하여 만든 육안검사 시편을 개발하여 기계의 특성을 파악한다. 이에 본 논문은 고품위가공의 한 방법으로 기계적 특성이나 성능 테스트규명을 위해, 표면조도, overshoot, 상한돌기, 직경감소와 미소지정, 열변형랑, 가공시간, 상.하방향 조도상차이등의 테스트항목을 선정하여 육안검사시편을 개발 및 가공함으로써 고속가공기의 특징을 분석하여 최적의 기계성능을 활용할 수 있게 하고자 한다.