산모혈과 제대혈에서 연농도에 관한 조사

이덕희,문종국,배강우,이용환,김진하,박강원 大韓産業醫學會 1996 대한직업환경의학회지 Vol.8 No.3

This study was conducted to evaluate the blood lead levels in 141 pregnant women who were not occupationally exposed to lead and their umbilical cord, and to identify some differences in blood lead levels by living area. The subjects were all delivered at St. Benedict Hospital in Pusan and the blood lead levels were measured by graphite furance atomic absorption spectrophotometer. The summarized results were as follows. 1. The geometric mean lead levels in maternal and cord blood were 8.0±1.8μg/dl, 5.0±0.6μg/dl respectively. 2. Lead levels in maternal(8.7±1.7μg/dl) and cord blood(5.4μ±0.7μg/dl) of industrial area(n=24) were higher than residential area(n=124) which were 7.9±1.7μg/dl and 5.0±0.6μg/dl respectively(p<0.05). 3. Maternal blood lead concentration was significantly correlated to cord blood lead concentration(r=0.6090, p<0.001), but other variables(maternal age, paternal smoking, birth weight, etc) were not correlated.

UHF 대역의 휴대전화 착신기능 제한 시스템의 설계 및 제작

남효덕,김종석,김병철 嶺南大學校 工業技術硏究所 2001 工業技術硏究所論文集 Vol.29 No.2

As demands grow for restricting use of cellular phones by attendants in the public places such as conference rooms, churches, and playhouses etc., a call blocking system against UHF band cellular signals is developed for other attendants who do not want to be disturbed by the phone rings. The idea of preventing a cellular phone from ringing was developed from the fact that the system radiates interferent signals having 0.1 to 0.05 watts of CW wave, makes it possible to increase the error rates of output signal of PSK modem, and hence makes the cellular phone Impossible to receive the right call signal. The system designed in this study was set up and tested in the several public places and found itself very effective.

전이균형(Transitional Equilibrium)을 이용한 인플레이션조세의 후생비용 분석

서종덕 大田大學校 社會科學硏究所 2005 社會科學論文集 Vol.24 No.1

본 연구에서는 신고전파의 성장모형을 이용하여 인플레이션의 진행에 따른 후생효과를 분석하고 있다. 정상상태 간에 존재하는 조정비용을 고려함과 동시에 조세를 모형에 도입하여 후생비용을 정태적인 측면과 동태적인 측면(전이균형)에서 분석하고 있다. 그 결과 조정비용의 존재와 조세의 왜곡효과가 존재하는 경우 후생비용의 크기는 기존의 연구결과 보다 크게 나타나고 있다. This paper uses the neoclassical growth model in which administration of policies is costly to evaluate the size of welfare cost of inflation tax. In addition, we consider the taxes on capital and labor which have effect on the size of welfare cost, so that we can find the equilibriums of both stationary and non -stationary. We find that the presence of adjustment cost increase the welfare cost of inflation. Second, the welfare cost of inflation in the case of higher rate of unemployment is lower. Finally, the interaction between monetary and fiscal polices makes the negative effect on policy maker so that welfare costs is more higher than without fiscal polices

飮用水 利用現況 및 家庭用 淨水器 管理實態

김정덕,박종안 순천향대학교 1993 논문집 Vol.16 No.3

本 硏究는 飮用水 改善方向에 基礎資料를 提示하고자, 1992年 10月부터 12月사이에 國民學校 學父母 1,540명을 대상으로 설문조사를 하고, 시중에 보급되고 있는 家庭用 淨水器 10종의 필터를 分析하여 다음과 같은 結果를 얻었다. 1. 수돗물을 飮用水 으로 利用하는 家庭은 地域別로 다소 差異를 보이고 있으나 약 50%에 불과하였다. 2. 生水나 藥水를 利用하는 家庭이 26.5%인데, 이들 中 69%가 生水나 藥水를 冷藏保管하지 않고 있어 細菌繁殖 등의 문제가 있으며, 生水나 約水 利用者의 85%가 3일 이상 保管하고도 끓이지 않고 마시고 있어 非衛生的인 것으로 나타났다. 3. 淨水場에서 消毒을 잘 하고 있다고 생각하는 사람은 8.7%뿐이고 수돗물을 그냥 마셔도 좋다고 생각하는 사람도 0.8%에 不過하였으며, 수도관의 상태를 우려하고 있는 사람도 63.4%이었다. 또한 수돗물을 먹을 때는 꼭 끓여서 먹는다고 하는 사람이 93.6%이었으며, 수도요금이 오르더라도 깨끗한 물을 공급받고 싶다는 사람이 91%이상인 바, 수돗물의 수질 개선을 크게 원하고 있었다. 4. 각 家庭의 물탱크 청소를 1년에 한번도 하지 않는 경우가 26.7%로 나타남으로써 급수 탱크에서 침전된 물질들이 계속 쌓여 오히려 오염을 유발할 소지가 있었다. 5. 淨水器 를 소유한 家庭은 전체 對象者의 약 20% 이었으나 실제 사용하는 家庭은 全體 대상자의 6.4%에 不過하였으며, 정수기를 使用하지 않는 이유는 효능을 믿을수 없어서가 51.5%, 통과수가 오히려 나쁘기 때문이 14%로 나타났다. 또한 應答者 중 80% 이상이 淨水器가 農藥, 페놀, THMs 등을 除去할 수 없다고 생각할 정도로 정수기 성능에 대하여 불신감이 높았다. 6. 淨水器의 필터 交換時가期 물 使用量과 관계가 있다는 것을 알고 있는 경우가 63.4%뿐이었고, 水質에 따라 사용해야 할 淨水器의 種類가 다르다는 것을 알고 있는 사람도 42.6%에 불과한바, 정수기의 규격기준이나 필터의 수명에 관한 사용 설명서가 확실하게 제시될 필요성이 있었다. 7. 應答者 中 90%이상이 性能 좋은 淨水器의 開發과 政府의 철저한 製造 檢査, 品質保證 및 追後管理를 바라고 있음이 나타났다. 8. 淨水器 필터에 KS 1급 이상의 活性炭素를 使用한 業體는 20%에 不過하였던바, 필터용 활성탄소의 품질 선정에 신중해야 함을 알 수 있다. This study aims at providing a foundamental data of the quality of drinkable water. For this study, a typical method of questionnair is used. A total of 1,540 parents of elementary schools was asked to fill out a brief factual questionnaire. The questionnaire includes some questions on water purifier used by general hounshold. The following results are obtained from the analysis of the questionnaire. 1. The average rate of housholds drinking city water is about 50%, although rates are different slightly according to sample areas. 2. The proportion of housholds drinking sales water or spring water accounts for 26.5%. However, 69% of those housholds does not keep sales or pring water in the refrigerator , having the problem of increasing bacillus. Furthermore, 85% of the housolds does not drinks raw sales or spring water within 3 days, and is thereby faced with an sanitary problem. 3. Regarding satisfaction degree on th city water, 8.7% of the total housholds surveyed satisfies the treatment of city-water at filtration plants, while merely 0.8% of such housholds thinks that unboiled city water is edible, and 63.4% of the total housholds answers that the state of water pipe is very serious. This results clearly shows that the supply of clean water is very desirable even though the price is increased at a high rate. 4. Contamination problems of water tank appear to be very critical because each houshold has a long period of cleaning interval; 26.7% of the housholds does not clean water tank even once a year. 5. Approximately 20% of the total housholds surveyed has water purifier. However, the only 6.4% among them actually uses water purifier. This is because the housholds believe that water purifier can not remove all the contaminants and hazardous materials such as heavy metals, pesticides, phenol, THMs, and etc. 6. About 63% of the housholds having water purifier knows that the exchange of filter is relate with the total volume of eater used. Also, 42.6% of the housholds recognizes that water purifier should be used according to the quality of water. This indicate that purifier should be used according to correct and valid instruction. 7. About 90% of the housholds wants a newly developed water purifier with good quality as well as a tough inspaction and after-assurance by government on water purifier. 8. Only 20% of the water-purifier manufacturing companies uses the KS-grading "activated carbon" filter in its products, so that every water purifier companies count on the efficiency of water purifier.

X' X + C가 비정칙일 때의 일반화능형회귀의 일반적 해의 유도와 해석

김종덕 부산 외국어 대학교 2004 外大論叢 Vol.28 No.-

Generalized ridge regression in which X is of size n×m with rank γ (≤(n, m)) is considered. A detailed derivation process for the estimated regression coefficients and response vectors is shown when the original X (or standardized X) is used instead of the orthogonally transformed one in the situation of possibly singular X'X + C. The regression vector is expressed in such a way that the transformed C is revealed

환경친화적인 무기/유기 Core-Shell의 제조에 관한 연구

설수덕,임재길,임종민,권재범,이내우 한국안전학회 2004 한국안전학회지 Vol.19 No.1

Composite particles using inorganic and organic chemicals were synthesized and the results of those reaction were compared to variation of temperature and agitation speed in presence of CaCO₃ which was adsorbed SDBS. Also the synthesises were optimized according to conversion rate of composite particles. In inorganic/organic core-shell composite particle polymerization, CaCO₃ adsorbed by 0.5wt% surfactant SDBS was prepared initially and then core CaCO₃ was encapsulated by sequential emulsion polymerization using MMA at the addition of APS 3.16X 10^(-3)mo1/L to minimize the coagulated PMMA particle itself during MMA shell polymerization. Encapsulated PMMA on CaCO₃ as inorganic/organic core-shell particles was verified by Fr-IR and DSC analysis. It was found that the CaCO₃ was very well encapsulated by PMMA as shell. The surfaces were distinctly found as spindle shape and broad particle distribution after capsulation.

감성돔, Acanthopagrus schlegeli의 종묘생산 및 성분화에 미치는 영향

한종석,김용구,라성주,윤호섭,이원교,김정,최상덕 國立 麗水大學校 環境問題硏究所 2002 環境硏究論文集 Vol.5 No.-

This study was carried out to produce the seeding of the larvae and juvenile of black sea bream, Acanthopagrus schlegeli in terms of artificial hatching, feeding behavior and growth rate in each factor. Total length of black sea bream larvae hatched was 2.57±0.35mm and after 50 days, total length was 22.08±3.74mm, 49.7% in survival rate. This research was conduced to confirm the effect of tributyltin and 2,4-dinitrophenol on the sex differentiation in Black Sea bream, Acanthopagrus schlegeli. Fish were reared of oral administration of tributyltin at 0.05, 0.5, 5㎍/g and 2,4-dinitrophenol at nominak concentration of 0.05, 0.5, 5, 50㎍/g diet from 156 days to 185 days after hatching. In the process of the differentiation until 156 days after hatching, gonads were composed testis. In contrast, 185 days after hatching, testis were composed of a number of spermatogonia and sperm duct. The female in the control in which sex differentiation of Acanthopagrus schlegeil was normally conducted was 100%. The experimental unit of estradiol-17β, it was 100% in 0.05㎍/g diet concentration, which was similar to the sex ratio of the control. And it was 100% in 0.5㎍/g diet concentration. In each experimental unit with 5, 50㎍/g diet concentrations, every individuals of them differentiated to males. About the experimental unit of tributyltin, the females were 100%, 100%, 100%, 100% and 100% in 0.05㎍/g, 0.5,㎍/g, 5㎍/g and 50㎍/g diet concentrations, respectively. About the experimental unit of 2,4-dinitrophenol, the males were 100% tn 0.05, 0.5, 5, 50㎍/g diet concentrations, respectively.

惡臭汚染 事例硏究를 통한 惡臭汚染 防止 및 管理對策

송덕만,최종만 울산대학교 1994 공학연구논문집 Vol.25 No.2

본 연구의 목적은 석유화학산업 지역에서 악취의 외부이동을 감축하기위한 방법론을 개발하고 악취제어사례를 예견하거나 석유화학산업 지역에서 악취영향을 점검하기 위한 악취오염 방지 및 관리전략 수립시 예비지침을 제공하기 위한 것이다. 실제 기상자료와 악취발생원강도를 ISCST 분산모델에 입력시켜 착지점에서의 악취농도수준(o. u.)을 계산할 수 있었다. 본 모델링연구는 1 악취단위전략과 악취완충거리의 개념을 도입하여 석유화학산업 지역에서의 악취제거 및 예측을 수행하는 독특한 방법이라 할 수 있다. 결론적으로, 1 악취단위전략과 악취완충거리 개념을 도입하여 풍하거리에 따른 지표면 악취 농도수준을 예측하는 악취 분산모델링 방법론은 공단에서 배출된 악취오염물질의 제어 및 예측을 위해 악취저감 대책을 위한 전략수립시 예비지침서로 사용될 수 있을 것이다. The objective of this study is to create a methodolgy for reductions in off-site odor migrations at petrochemical industrial sites, and to provide the preliminary guideline in predicting the odor control episodes or in establishing the odor pollution prevention and management strategies for review of odor impact at petrochemical industrial sites. By incorporating the actual meteorological data and odor source strength into the ISCST dispersion model, odor concentration levels(o. u.) at receptors could be calculated. This odor modeling study is a unique approach to odor control and predictions at petrochemical industrial sites using 1 odor unit strategy and odor buffer distance concepts. Consequently, this odor dispersion modeling methodology predicting the ground-level downwind plume centerline odor concentration levels by using 1 odor unit strategy and odor buffer distance concepts can be used as a preliminary guideline in establishing odor reduction management strategy for odor control and prediction at industrial complex sites.

CRW형식 무인항공기 추진시스템의 밸브작동을 고려한 비행모드 전환에 따른 천이성능 특성 연구

공창덕,박종하,강명철,양수석 朝鮮大學校 機械技術硏究所 2005 機械技術硏究 Vol.8 No.1

본 연구는 CRW형식 무인항공기 추진시스템의 밸브작동을 고려한 비행모드에 따른 천이 성능특성을 파악하기 위해 SIMULINK를 이용하여 모델링 하였다. 주 엔진시스템의 천이 모사에는 ICV방법이 적용되었다. 그리고 밸브시스템은 로터리 덕트와 메인 덕트로 빠져나가는 유량을 제어하는 시스템으로서 밸브를 통해 로터리 덕트로 빠져나가는 유량과 메인 덕트를 빠져나가는 유량의 합은 터빈의 출구 유량과 같다는 가정하에 수행되었으며, 이 때 밸브각 변화에 따른 손실, 유량 및 유효면적 등이 고려되었다. 성능해석은 비행 천이 영역인 고도 1Km 비행마하수 0.1에서 엔진최대회전수시 회전익 모드에서 고정익 모드로 변환시외 고정익 모드에서 회전익 모드로 변환 경우들이 수행되었다. In order to investigate transient behaviour of the CRW(Canard Rotor Wing) type UAV(Unmanned Aerial Vehicles) propulsion system during flight mode transition considering flow control valve operation, the propulsion system was modelled using SIMULINK commercial program. For transient simulation of the main engine system, the ICV(Inter-Component Volume) method was applied. The valve system is to control the gas flow of the rotary duct system and the main duct system, and the analysis was performed with an assumption that the total gas mass flow of the main engine is the same as summation of the rotary duct flow and the main duct flow, and with consideration of valve loss, flow rate and effective area in valve angle variation. The performance analysis was carried out during flight mode transitions from the rotary flight mode to the fixed wing flight mode and vice versa mode at altitude of 1Km, flight Mach number 0.1 and maximum engine rpm.

OBD-2의 열 변색 현상에 관한 열역학적 연구

許永德,金明建,金鍾珪 단국대학교 1995 論文集 Vol.29 No.-

The termochromism of OBD-2 has been examined. The OBD-2 exists as a colorless lactone in aprotic solvents. However, the OBD-2 exists in the form of an equilibrium imxture of a colored zwitter-ion and a colorless lactone in protic solvents. When an acid is added to the solution, the OBD-2 exists and equilibrium mixture as a colorless lactone and a colored cation even in aprotic solvents. In order to understand the interaction between the OBD-2 and the solvent, absorption spectra of the OBD-2 in various solvents were measured. The systematic increase of the λ_max of the OBD-2 correlate with the hydrogen-bond donor ability of the solvent in neutral solution. The thermodynamic parameters of the OBD-2 has also been investigated. From the variation of absorbance with temperature, the standard enthalpy changes △H^0 of the equilibrium between the lactone and the zwitter-ion in various solvents have been determined. The standard enthalpy change △H^0 is approximately -7 kJ/mol in protic solvents. In acidic solution, the standard enthalpy change is measured to be to zero in protic solvents within the experimental error. When the carboxylic group is protonated in acidic solution, a poor interaction between the dye and the solvent is expected.