대구지역의 대기오염도 특성평가(I) : 지역별 및 계절별 농도변동을 중심으로 Locational and Seasonal variations

백성옥,최진수,황승만,김광은 嶺南大學校 環境問題硏究所 1996 環境硏究 Vol.15 No.2

본 연구는 대구지방환경관리청과 유관기관 등에서 과거 7년간(1988~1994년) 측정한 대기질 관련자료중 아황산가스, 분진, 일산화탄소, 질소산화물 및 오존을 대상으로 통계분석하여 각기 배출강도가 다른 지역별 농도분포 특성을 평가하였고 대구지역의 전반적인 대기질 변화추이를 파악하였다. 그 결과 각 지점별 아황산가스의 농도는 전형적인 동고하저형을 나타내었으며, 도시가스공급과 황함량규제등 연료변환 정책의 효과로 인해 점차적으로 감소하고 있는 추세를 보이고 있다. 부유분진은 결측치가 많아 장기적인 농도변화추이를 판단하기는 어려웠으나 아황산가스와 같이 큰 계절적인 변동은 보이지 않았다. 질소산화물의 전반적인 농도분포는 장기 환경기준치 50ppb를 초과하지 않는 수준이었으나 최근엔 이동배출원의 영향이 가중되어 그 농도가 꾸준히 증가하는 추세인 반면 동고하저형의 계절적인 변동을 나타내는 일산화탄소는 가정용 무연탄 사용량의 감소로 대기중 일산화탄소의 농도는 점점 감소하고 있는 추세이다. 오존은 전반적으로 일사량이 많은 하절기에 농도가 높았고 동절기에는 농도가 낮은 경향을 보였다. 한편 주요 대기오염물질의 장·단기 기준달성도를 비교분석한 결과 대구지역의 대기오염물질중 아황산가스의 고농도 발생빈도는 공업지역에 집중되어 있었으며 질소산화물과 일산화탄소는 아직은 장·단기 환경기준을 초과하지 않는 수준으로 나타났고, 분진과 오존의 경우는 공업지역 뿐만 아니라 전지역에서 그 발생빈도가 유사하게 나타났다. In this study, characteristics and distributional patterns of the concentrations of air pollutants in Taegu area were evaluated using a data-base established from the ambient air quality monitoring stations for the period of 1989 to 1994. The result of this study demonstrated that in each sampling site, the SO_2 concentrations were much higher in winter than those in summer. However, a decreasing tendency was clearly shown in the annual variation of SO_2 concentrations, largely due to the use of LPG instead of anthracite coal for local heating systems and to the fuel policy of using lower sulfur content fuel in industrial sectors. Unlike SO_2, there was no distinct seasonal variation in the concentrations of suspended particulate matter. Concentrations of NO_x were found to be generally lower than the long term ambient air quality standard (50 ppb). The NO_x concentration has been gradually increased, reflecting the rapidly increased number of vehicles In this area, while the CO levels In ambient air were declind because of the reduced use of coal for domestic purposes. The Ozone concentrations in Taegu area exhibited that there has been already photochemical smog phenomena during the summer season when the insolation is strong.

Pyriminobac-methyl과 azimsulfuron 합제의 신규제형인 분산형 정제에 대한 독성 평가

백경진,이동연,이상훈,김태원,정두순,임종환,김명석,박병권,윤효인 충남대학교 수의과대학 동물의과학연구소 2004 動物醫科學硏究誌 Vol.12 No.-

Dispersible tablets disintegrate either to form a stabilized suspension rapidly in water, or to disperse instantaneously in the rice field without the aid of water. In this study, the newly formulated dispersible tablet form of herbicidal combination, pyriminobac-methyl and azimsulfuron, was evaluated the safety for human and animals in the toxicological viewpoints. The LD_(50) value of dispersible tablet form for pyriminobac-methyl and azimsulfuron was above 2,500 mg/kg for the oral route and above 2,000 mg/kg for the dermal route. It is considered to have low acute oral and dermal toxicity based on the findings of the present studies. In addition, the combination of pyriminobac-methyl and azimsulfuron showed mild skin irritant under the conditions of this study and conjunctival redness and slight opacity on cornea appeared from 1 hour after application.

조혈모세포이식 후 골성장인자의 변화 및 골대사에 미치는 영향 : Impact on Bone Mineral Metabolism

백기현,오은숙,오기원,이원영,김혜수,권순용,한제호,강무일,차봉연,이광우,손호영,강성구,김춘추 대한내분비학회 2002 Endocrinology and metabolism Vol.17 No.5

연구배경: 각종 장기이식의 시행이 많아지고 이식 후 생존율이 증가함에 따라 이식 후 합병증에 대한 관심 또한 높아지고 있다. 조혈모세포이식 후에도 다양한 내분비적 합병증이 발생할 수 있으며 골격에 대한 합병증도 문제점으로 대두되고 있다. 조혈모세포 이식 후 발생하는 골소실에는 이식 후 초기의 골형성 저하와 골흡수 증가가 중요한 역할을 담당하리라고 추측되는데 이러한 골재형성불일치(biochemical uncoupling)에 골 성장인자들이 미치는 영향에 대해서는 알려진 바가 없다. 본 연구에서는 조혈모세포이식 전, 후로 말초 혈액에서 IGF-I, FGF-2, M-CSF같은 성장인자의 변화를 알아보고, 이들 성장인자의 변화가 조혈모세포이식 후의 골형과 골흡수에 미치는 영향 및 이식 후 발생되는 골량 소실과의 연관성을 확인해 보고자 하였다. 방법: 여러 가지 혈액질환으로 인해 동종 골수이식을 시행 받은 환자들을 전향적으로 관찰하였으며 이식 전 및 이식 후 1주, 2주, 3주, 4주 및 3개월, 6개월 1년에 말초 혈액에서 골교체표지자를 측정하였다. 이식 전 및 이식1년 후에 요추골 및 대퇴골 골밀도를 측정할 수 있었던 36명의 환자들을 대상으로 냉동 보관되어 있던 혈청을 이용하여 IGF-I, FGF-2 및 M-CSF를 시기별로 측정하였으며 이들 성장인자와 골교체표지자의 변화 및 골밀도 변화 사이의 상관관계를 확인하였다. 결과: 골흡수 표지자인 혈청 ICTP는 이식 전에 비해 이식 후 4주까지 점차 의의 있게 증가하다가 이후 6개월까지 더욱 증가한 후 감소하였다. 골형성 표지자인 osteocalcin은 이식 후 3주까지는 점차 감소하다가 이후 증가하여 이식 후 3개월 및 6개월에 기저치보다 통계적으로 유의하게 증가한 후 감소하였다. 혈청 IGF-I과 FGF-2는 각각 이식 후 3주 및 1주까지 의미있게 감소하다가 이후 증가하였으며 혈청 M-CSF는 이식 후 1주째에 기저치에 비해 의미 있게 증가하였다가 이후 기저치로 회복되었다. 이식 1년 후 평균 요추부 골밀도는 5.2% 감소하였고 평균 근위대퇴골 골밀도는 11.6% 감소하였다. 이식 전 및 이식 후 3주에 측정한 IGF-I과 같은 시기에 측정한 오스테오칼신 사이에 유의한 상관관계가 관찰되었으며 이식 후 3주째의 M-CSF와 골흡수표지자인 M-CSF 사이에서 의미 있는 양의 상관관계를 관찰할 수 있었다. 이식 후 3주 및 3개월에 IGF-I이 낮은 환자일수록 이식 1년 후 근위대퇴골에서의 골소실이 많은 것으로 분석되었다. 결론: 조혈모세포이식 후 발생하는 골소실에는 기존에 알려진 기저질환의 영향, 성호르몬의 감소, 면역억제의 투여, 골수기질세포와 조골세포의 손상 및 이식초기 사이토카인의 변화이외에도 골성장인자가 관련이 있음을 확인하였고, 이는 이식 후 발생되는 골량소실에 중요한 역할을 할 것이라고 사료된다. Background: A loss of bone mass is usually detected after a bone marrow transplantation (BMT), especially during the early post-transplant period. We recently reported that enhanced bone resorption following a BMT was related to both the steroid dose and the increase in IL-6. We also suggested damage to the marrow stromal microenvironment, by myoablation, partly explains the impaired bone formation following a BMT. It is well known that some growth factor play important role in bone growth and osteogenesis. However, the pathogenetic role of bone growth factors in post-BMT bone loss is unknown and data on the changes in the growth factors, in accordance with bone turnover markers and bone mineral density (BMD) changes are scarce. We investigated changes in bone growth factors such as IGF-I (Insulin-like growth factor-I), fibroblast growth factor-2 (FGF-2) and Macrophage colony stimulating factor (M-CSF), during the post-BMT period, and assessed whether the growth factor changes influenced the bone turnover and post-BMT bone loss. The present study is the first prospective study to describe the changes in bone growth factors following a BMT. Methods: We prospectively investigated 110 patients undergoing a BMT, and analyzed 36 patients (32.4±1.3 years, 17 men and 19 women) whose BMDs were measured before, and 1 year after, the BMT. The serum biochemical markers of bone turnover were measured before, 1, 2, 3 and 4 weeks, 3 and 6 months, and 1 year, after the BMT. The serum, FGF-2, IGF-I and M-CSF levels were measured before and 1 and 3 weeks, and 3 months after the BMT. The correlation between the changes of growth factors and various bone parameters was analyzed. Results: The mean bone losses in the lumbar spine and total proximal femur, calculated as the percentage change from the baseline to the level at 1 year, were 5.2(p<0.05) and 11.6%(p<0.01), respectively. the serum type I carboxyterminal telopeptide(ICTP), a bone resorption marker, increased progressively until 6 months after the BMT, but thereafter decreased, to the base value after 1 year. Serum osteocalcin, a bone formation marker, decreased progressively, until 3 weeks after the BMT but then increased transiently, and finally returned to the base level at 1 year. The serum IGF-I and FGF-2 also decreased progressively until 3 weeks 1 week after the BMT, respectively, then increased to the base values at 3 months. The serum M-CSF increased briskly at 1 week post-BMT, then decreased to the base level. There were positive correlations between the percentage changes from the baseline proximal femur BMD and the IGF-I levels 3 weeks and 3 months (r=0.52, p<0.01, r=0.41, p<0.05) post BMT. A significant correlation was found between the IGF-I and osteocalcin levels pre-BMT, and 3 weeks after the BMT. Another positive correlation was found between the M-CSF and the ICTP levels at 3 weeks post BMT (r=0.54, p<0.05). Conclusion: In conclusion, there were significant changes in the serum IGF-I, FGF-2 and M-CSF levels in the immediate post-BMT period, which were related to a decrease in bone formation and loss in the proximal femoral BMD during the year following the BMT (J Kor Soc Endocrinol 17:664∼674, 2002).

판매지원 에이전트에서의 사례기반추론 방법

成百均 충주대 산업과학기술연구소 2000 産業科學論文集 Vol.8 No.-

In this paper, We describe a design of sales agent for negotiation during sales support on the Internet within Case-Based Reasoning(CBR) solutions. First, We propose an multi-agent system which can effectively search complex product on the WWW. And we represent databases and case-bases and propose a CBR cycle for sales agent. We then implement some of them in a prototype for a sales agent and a case study is shown where preliminary approaches are used to negotiate with a customer about his demands and available products in a CBR-based Electronic Commerce solution.

사례 기반 추론을 이용한 사용자 인터페이스 에이전트에 관한 연구

성백균 忠州大學校 1999 한국교통대학교 논문집 Vol.34 No.2

Given that the Web has grown immensely beyond its original homogeneous origin, it is now practically impossible for a Web user to find all her or his informaiton interests through surfing. Intelligent Agents promise to address these user needs. This paper describes the design of user interface agent using CBR(case-based reasoning) for the internet search system. First, After briefly surveying to internet agents, adaptive interface agents and case-based reasoning, We design an internet agent system which can effectively search the index database and serve as an electronic host to visitors of a Web site. We then describe robot agent and indexing agent that extracts concept graph using hyper-link information of web document, and design an user interface agent model using case-based reasoning. Although our system using case-based reasoning is not advanced, it can dfficiently filter the information on the internet according to users' personal interests compared with other search systems.

충주시에서의 LPG 탱크로리 수송중 위험성 평가에 관한 연구

白種培,李聖一 忠州大學校 1997 한국교통대학교 논문집 Vol.32 No.1

The demand of LPG and LNG will increase continuously due to high calories, clearness, and convenience for usage. These gases are used widely for power plants, industrial plants, and domestic fuel. But accidents related with gas are increasing in proportion to the increment of gas usage. Especially, LPG has high ignitability due to a weak dispersion to air and an accumulation at low place because LPG is heavier than air. There are many hazards during transportation as well as production, storage, and usage of LPG. Commonly, tanklorry is used for inland transportation of LPG. If tanklorry were to raise leakage incidents and then LPG is released during transportation, it will have serious effects on the environment as well as human damage to surrounding area. In this study, therefore, hazards which cause LPG of tanklorry to leak during transportation were identified and the risk of LPG transportation was assessed quantitatively. Accordingly, the result of this study might be a useful measure for predicting damage and preparing safe transportation strategies of LPG tanklorry.

자기연상 학습 신경망과 부호 입력 변수를 이용한 종합주가지수 "왼쪽어깨" 패턴 검출 : Associative Neural Network and Sign Variables

백진우,조성준 한국경영과학회 2000 한국경영과학회 학술대회논문집 Vol.- No.2

We proposed a neural network based "left shoulder" detector. The auto-associative neural network was trained with the "left shoulder" patterns obtained from the Korea Composite Stock Price Index, and then tested out-of-sample with a reasonably good result. A hypothetical investment strategy based on the detector achieved a returm of 132% in comparison with 39% returm from a buy and hold strategy

발생원 유형에 따른 공기 중 휘발성 유기화합물의 비산배출 특성 평가

백성옥,김미현,서영교 한국대기환경학회 2003 한국대기환경학회지 Vol.19 No.4

In this study, the fugitive emission characteristic^ of airborne volatile organic compounds from different source categories were evaluated with respect to the concentrations measured in the vicinity of the sources. A total of 22 different sources were investigated, including gasoline storage and filling stations, painting spray booth, laundry, printing offices, textile industries, and a number of environment sanitary facilities such as landfill, wastewater treatment and incineration plants The target VOCs included 83 individual compounds, which were determined by adsorption sampling and thermal desorption coupled with GC/MS analysis. Overall, the aliphatic compounds appeared to be the most abundant class of compounds in terms of their concentrations, followed by aromatic, and halogenated hydrocarbons. As a single compound, however, toluene was the most abundant one, explaining 11% of the total VOC concentrations as an average of all the dataset. Among source categories. petroleum associated sources such as gasoline storage/filling stations, and laundry factory were identified as the most significant sources of aliphatic hydrocarbons, while aromatic VOCs were dominantly emitted from the sources handling organic solvents, such as painting booth, printing offices, and textile dyeing processes. However, there was no apparent pattern in terms of the contributions of each group to the total VOCs concentrations in environmental sanitary facilities. It was also found that the activated carbon adsorption tower installed for the VOC emission control in some facilities do not show any effective performances, which may result in the increased VOC levels in the ambient atmosphere.

사례기반추론 방법을 이용한 전자우편물 자동 생성에 관한 연구

成百均 충주대학교 산업과학기술연구소 2002 産業科學論文集 Vol.10 No.-

In this paper, We describe a system on automatically construction E-mail documents in a Case-Based Reasoning(CBR) model. First, After briefly surveying to case based reasoning and intelligent agents, we present an multi-agent system which is composed of E-mail Documents Analysis Agent, Index Agent, Search Engine and E-mail Documents Construction Agent. Especially, the agent system on automatically construction E-mail documents makes it possible to propose a new cycle of CBR and a method of computing similarity. And we represent databases and case-bases and propose a CBR cycle for the agent. We then implement some of them in a prototype for the agent and a case study. In the future, the study of Data-mining Technique will help the system develop into a useful agent which can adapt itself to many kinds of users.

광탄성 프린지 위상이동법을 적용한 디스크의 등경 및 등색프린지 분리법에 관한 시뮬레이션

백태현,김명수,조성호 한국비파괴검사학회 2001 한국비파괴검사학회지 Vol.21 No.2

광탄성법은 전체적인 응력장 해석을 위하여 가장 많이 사용되는 방법중의 하나이다. 광탄성법에서 주응력의 차이와 방향은 등색선과 등경선으로 나타난다. 재래식 방법으로는 주응력 방향은 평면 편광기의 편광자와 검광자를 동시에 회전시켜 수작업으로 측정하며, 이를 타디보간법이라 한다. 이러한 방법은 전체적인 응력장 해석시 매우 번거로우며 많은 시간이 걸린다. 재래식 광탄성법에서는 광탄성 프린지로부터 등경선을 분리시킬 수 없다. 본 연구에서는 광탄성이론을 Jones행렬로 나타내고 4단계와 8단계의 위상이동법에 대해서 기술하였다. 컴퓨터시뮬레이션을 통하여 압축하중을 받는 원형디스크의 광탄성 프린지로부터 등경선과 등색선을 분리시킬 수 있는 시험을 하였다. 디스크의 프린지는 응력-광 법칙에 의하여 생성하였다. 8단계 위상이동법으로 얻은 등경선과 등색선의 크기를 이론으로 계산한 값과 비교하였다. 컴퓨터 시뮬레이션으로부터 광탄성 프린지로부터 등경선과 등색선을 분리시킬 수 있는 가능성ㅇ르 예시하였다. Photoelasticity is one of the most widely used methods for whole field stress analysis. In photoelasticity, the difference and the directions of the principal stresses are given isochromatic and isoclinic fringe patterns. Conventionally, principal stress directions are measured by rotating the polarizer and analyzer of a plane polariscope at the same time. This is known to be the Tardy compensation method. This measurement can be very tedious and time consuming in whold field analysis. It is not possible to separate isoclincs from photoelastic fringes by conventional photoelastic technique. In this study, photoelastic theory is represented by Jones matrices and 4-steps and 8-steps phase shifting methods are described. A feasibility study using computer simulation is done to separate isoclincs and isochomatics from photoelastic fringes of a circular disk under diametrical compression. Fringe patterns of the disk are generated using stress optic law. The magnitudes of isoclincs and isochromatics obtained from 8-step phase shifting method are compared with those of theories. From computer simulation, it is verified to separate isoclincs and isochmatics from photoelastic fringes.