Low Impact Development(LID)를 적용한 비점오염저감 시설의 도로노면 강우유출수에 대한 저류효과와 중금속 축적 모니터링

정석영,장순웅 한국방재학회 2014 한국방재학회 학술발표대회논문집 Vol.2014 No.-

본 연구는 도로의 Low Impact Development(LID) 시설에서 노면유출수의 저류와 토양내의 중금속 축적을 모니터링하였다. 경기도 A시에 위치한 시설로 기존가로수 하향식재와 나무화분 여과상자의 가로수 형태가 있으며, 식생 저류조 형태의 식생플랜트와 식생체류장치로 총 4개의 시설에 대하여 모니터링을 실시하였다. 강우에 실시된 4회의 모니터링에서 시설로 유입된 누적 강우유출수는 0.07~0.77 m3의 범위로 나타났으며, 가로수 형태 시설의 강우 유출수에 대한 시설 유입율은 평균 14.9%였다. 식생 저류조 형태의 경우 평균 4.6%의 유입율로 강우 유출수에 대한 저류능력을 나타내었다. 토양 의 중금속은 표층으로부터 10 cm의 토사를 채취하여 농도변화를 계절(여름, 가을, 겨울)에 따라 모니터링하였다. 타이어의 마모에 의해 발생하는 카드뮴(Cd)의 경우 식생플랜트 시설의 초기 기저농도 0.0014 mg/kg에서 겨울에는 0.0304 mg/kg으로 증가하였다. 나무화분 여과상자에서는 납(Pb)이 0.0263 mg/kg에서 0.0606 mg/kg으로 축적된 것을 확인하였다. 이러한 LID시설의 유량 저류는 도심의 불투수층에서 발생하는 강우 유출수가 하천으로 유입되어 유발되는 홍수 및 수해에 대한 방재 효과와 시설 내 중금속 저감을 기대 할 수 있는 것으로 나타났다.

무딘 물체 주위의 극초음속 유동 해석

정석영,노오현,이동호,변영환,김범수,변우식 한국항공우주학회 1993 한국항공우주학회 학술발표회 논문집 Vol.- No.-

무딘물체 주위의 열적/화학적 비평형 유동 해석

정석영,노오현,변우식 한국항공우주학회 1995 한국항공우주학회 학술발표회 논문집 Vol.- No.-

원추형 압력 Probe 시스템에서 멱 평균을 이용한 마하수 추정

정석영,이정화 한국항공우주학회 2015 한국항공우주학회 학술발표회 논문집 Vol.2015 No.11

풍동시험이나 비행시험에서 유동 변수를 측정하는데 널리 사용하는 압력 측정 시스템중 3개의 전압을 사용하는 원추형 압력 측정 시스템에 대하여 초음속 유동의 마하수를 추정하는 기법에 대한 연구를 수행하였다. 초음속 유동 속에서 측정된 전압은 주어진 형상에 대하여 유동의 마하수와 받음각의 영향을 받기때문에 마하수 추정 기법을 위해 받음각의 영향을 줄이도록 압력 처리 방법을 구성하여야 한다. 원추 위아래 면의 전압은 받음각에 따라 변하므로 그 영향을 상쇄하기 위해 평균을 취하여 대푯값을 산출하는데, 평균 방법에 따라 받음각의 영향을 감소시키는 정도가 다르다. 일반적으로 사용하는 산출 평균보다 멱 평균을 사용할 경우 받음각 영향을 더 감소시킬 수 있어 마하수 추정의 정확도를 올릴 수 있을 것으로 기대된다. A process of flow variable estimation with power-average technique is developed for conical probe system consisting of three pitot probes utilizing in wind-tunnel and flight test in order to measure the flow Mach No. and the flow angles. Flow angle greatly affects pressures measured by the probes located on the lee side and wind side of the cone and usually arithmetic average value of these two pressures is used to make the representative pressure and to calculate the pressure ratio with the pressure from the cone tip. Besides the arithmetic average, three average methods were chosen and the power-average gave the best results.

Soccer Angles와 이차곡선

정석영,정순진 한국수학교육학회 2011 수학교육 학술지 Vol.2011 No.2

원추유동이론을 이용한 원추형 압력 Probe 시스템의 특성 분석

정석영 한국항공우주학회 2014 한국항공우주학회 학술발표회 논문집 Vol.2014 No.11

풍동시험이나 비행시험에서 유동 변수를 측정하는데 널리 사용하는 압력 측정 시스템중 3개의 전압을 사용하는 원추형 압력 측정 시스템에서 압력 측정이나 유동 변수 추정의 성능을 분석하였다. 원추 유동이론을 이용하여 원추 주위의 압력장과 마하수 분포를 해석하여 측정되는 전압력을 예측하고 마하수와 받음각에 따른 압력 특성을 계산하였다. 측정되는 전압력의 비와 받음각의 영향을 고려하여 평균화된 대푯값을 정의하였고 마하수와 받음각에 따른 특성을 분석하였다. 마하수에 따른 압력비의 변화는 마하수 추정에 사용하기에 충분하다고 판단되나, 받음각에 따른 영향이 있어 오차로 작용할 것으로 생각된다. Probe의 위치에 따른 영향을 분석하였으며 위치각이 작을수록 압력 편차가 작아져서 추정 오차가 줄어들 것으로 예상된다. A process of flow variable estimation with power-average technique is developed for conical probe system consisting of 3 pitot probes utilizing in wind-tunnel and flight test in order to measure the flow Mach No. and the flow angles. Conical flow theory is utilized to analyze pressure field and Mach number distribution around the cone and predict the measured value of total pressure. Averaged pressure ratios, defined as tip pressure over cone pressures and averaged to eliminate the effects of angle of attack, are sufficiently approximated with 3-order polynomials. However, the deviation of averaged pressure ratio still remains and affect the accuracy of Mach number estimation. The smaller angle of probe location gives the lesser deviation of pressure ratio.

Evaluation for Protective Effect of CPV-2 and CPV-2b Vaccines against a Korean CPV-2a Isolate in Pups

정석영,이준석,김현태,김두 한국임상수의학회 2014 한국임상수의학회지 Vol.31 No.5

We evaluated the change of quadriceps angle (QA) after tibial tuberosity transposition. Twenty-nine animalsand 37 limbs of the total 62 case possibilities qualified for this study. The preoperative QA was 24.02 ± 4.02 in grade2, 26.08 ± 5.66 in grade 3 and 30.25 ± 7.41 in grade 4. The postoperative QA was 21.25 ± 3.24 in grade 2, 19.16 ± 3.92in grade 3 and 19.72 ± 7.30 in grade 4. The postoperative QA for all grades significantly decreased when comparedwith the preoperative QA (P < 0.05). However, the postoperative QA values were not within the normal range, althoughthe dogs’ prognosis remained good during the 4-month follow-up period. These results suggest that postoperative The aim of this study was to determine if vaccines containing CPV-2 or CPV-2b provided protection againstchallenge with a recent Korean CPV-2a isolate. Twenty mongrel pups aged 9 weeks old were used. The commercialCPV-2 or CPV-2b vaccines were administered to each of the 8 pups thrice every 3 weeks, respectively. Two weeksafter the last vaccination, all pups were challenged with CPV-2a (VR00174 strain) 1 × 106 TCID50. Clinical signs, fecalexcretion of challenged CPV, and serological response of pups were observed for 2 weeks after challenge. All vaccinatedpups did not display any clinical signs of disease after challenge with Korean CPV-2a isolate, whereas all non-vaccinatedpups exhibited mucoid or hemorrhagic diarrhea, vomiting and anorexia. In all non-vaccinated pups, the virus couldbe detected in feces from 4 days after challenge, whereas in vaccinated pups, no evidence of viral excretion couldbe detected. Two of 4 non-vaccinated pups died 6 days after the challenge. This study showed that the two commercialCPV-2 and CPV-2b vaccines were effective in preventing infection and/or disease caused by the Korean CPV-2a isolate We evaluated the change of quadriceps angle (QA) after tibial tuberosity transposition. Twenty-nine animalsand 37 limbs of the total 62 case possibilities qualified for this study. The preoperative QA was 24.02 ± 4.02 in grade2, 26.08 ± 5.66 in grade 3 and 30.25 ± 7.41 in grade 4. The postoperative QA was 21.25 ± 3.24 in grade 2, 19.16 ± 3.92in grade 3 and 19.72 ± 7.30 in grade 4. The postoperative QA for all grades significantly decreased when comparedwith the preoperative QA (P < 0.05). However, the postoperative QA values were not within the normal range, althoughthe dogs’ prognosis remained good during the 4-month follow-up period. These results suggest that postoperative QAoutside of the normal range may be allowed clinically. and 37 limbs of the total 62 case possibilities qualified for this study. fasting glucose, have been gradually recognized as important prognostic factors in disease progression. However, todate, no study has investigated glucose abnormalities in dogs with chronic mitral valve insufficiency (CMVD). Thus,we hypothesized that glucose metabolism abnormalities due to heart failure may develop in dogs with CMVD. Aprospective study was performed on 113 client-owned dogs with variable CMVD severities. Serum insulin, glucagon,fructosamine, and glucose concentrations were measured, and insulin resistance was determined using the homeostaticmodel assessment (HOMA) score. The serum insulin concentration had a significant inverse association with the heartfailure severity. However, there was no significant association between the heart failure severity and fructosamine,HOMA score, and fasting blood glucose. Insulin, fructosamine, and HOMA had a significant positive association withbody condition scores (BCS), whereas glucose had no association. This study found that insulin secretion in dogswith naturally occurring heart failure due to CMVD might be compromised as the disease worsens

국내 성견의 개 디스템퍼 바이러스에 대한 중화항체가 조사

정석영,안소저,장권식,박선일,김두 한국임상수의학회 2009 한국임상수의학회지 Vol.26 No.5

There were outbreaks of canine distemper in Korea from the late 1990's to the early 2000's even though modified live CDV vaccines had been used as the same way as before. The present study was undertaken to investigate the levels of neutralizing antibodies in the Korean dog population, and the factors associated with the levels, with special reference to the vaccination history of the dogs. A total of 772 serum samples were from clinically healthy dogs with over one year old throughout the Korea from January 2003 to April 2004. Details on the sex, breed, age, vaccination status and disease histories were recorded. The level of neutralizing antibodies titer was determined with a modified version of the microneutralization test. Titers over 16 were classified as protective CDV antibody titers. The overall rate of adult dogs with protective antibody titers was 96.0%. The dogs with protective antibody titers varied depending on age, sex, rearing environment and vaccination status. Because the majority of healthy adult dogs in Korea had adequate serum antibody titers against CDV and the immunity provided by the vaccinations is claimed to last for several years, annual revaccination protocol for CDV in adult dogs should be reconsidered.

Prevalence of Canine Coronaviral Enteritis in Korea

정석영,안소저,박선일,김두 한국임상수의학회 2010 한국임상수의학회지 Vol.27 No.3

Canine coronavirus (CCV) is a cause of sporadic outbreaks of enteritis in dogs. This study was performed to carry out epidemiological investigation on the recent outbreaks of CCV enteritis of dogs and determined the potential prognostic factors affecting the survival of dogs. The 131 (34.4%) out of 381 fecal samples collected from dogs with enteritis were positive for CCV by RT-PCR. The fecal samples contained genotype I (30.5%), genotype II (29.0%),and both genotypes (40.5%) of CCV. The majority of dogs with CCV infection ranged 6-18 weeks of age. Age over 18 weeks was significantly associated with higher survival rate (P < 0.05). Of the clinical signs examined, dogs without anorexia were significantly higher survival rate (P < 0.01). The 90.1% of dogs with CCV infection were co-infected by CCV and CPV-2. From the results of this study, it can be concluded that CCV infection is widespread in the Korean dog population and CCV may be attributed to be one of the important agents causing enteritis in pups.

보험회사의 수평적 리스크관리 평가체제 분석 -RAS식 설문조사방식을 기초로-

정석영,류건식 보험연구원 2002 보험금융연구 Vol.36 No.-

본 논문은 국내에서 영업활동을 하고 있는 전 보험회사를 대상으로 설문조사를 실시하여 수평적 리스크관리평가 체제를 보험회사 형태별, 규모별, 리스크관리 수준별로 실증분석 하였다. 수평적 리스크관리평가 체제라는 관점에서 보았을 때 리스크관리 체제가 상위 체제로 가면서 보험회사 규모면에서 대형사/중소형사의 차이가 뚜렷하게 나타나고 있어, 리스크관리의 전략수립이 어느 때보다도 요구된다. 또한 본 논문의 실증분석에 의하면 우리나라도 보험회사(특히, 중소형사)의 특성에 맞는 리스크관리 체제를 구축하는 방향으로 이루어져야 할 것으로 사료된다. 즉, 각 보험회사의 특성, 핵심 리스크관리 분야를 파악하여 이에 한정된 자원을 투입하여 리스크관리의 효율성을 증대시킬 수 있는 새로운 패러다임이 요구되고 있다. We conduct a survey for insurance companies and analyse the insurer`s risk management using the horizontal risk management framework in terms of the type of business, the size of company, and the level of risk management. Results indicate that it is required to construct an appropriate strategy in risk management, since there are huge differences in the level of risk management among insurance companies when we use the size of the firms as an independent variable. Specifically, the small and medium(S&M) companies need to construct the risk management structures which take account for characteristics of their own businesses. Conclusively, it is time to change risk management toward the new paradigm such that insurance companies including S&M firms evaluate core parts and characteristics of their businesses and identify the priorities of the parts of risk management. By doing so, they could improve efficiency in risk management by investing their limited resources on the top priority.