공간통계기법을 이용한 도로교통기반의 온실가스 관한 연구 -대구광역시를 대상으로-

이상우,이승욱,이승엽,홍원화,Lee, Sang Woo,Lee, Seung Wook,Lee, Seung Yeob,Hong, Won Hwa 한국공간정보학회 2014 한국공간정보학회지 Vol.22 No.1

본 연구는 대구광역시의 주요도로를 대상으로 공간통계기법을 이용하여 도로교통 온실가스 배출량을 신뢰성있게 예측하여 추정된 배출량으로 행정구별에 따라 도로교통에서 발생한 온실가스 배출량을 산정하는 것을 목적으로 하였다. 첫째, 주요도로의 교통량 관측지점에서 실시간으로 조사한 교통량을 이용하여 관측지점에서 발생한 온실가스 배출량을 산정하였다. 둘째, 일반 크리깅(Universal Kriging)기법을 이용하여 공간적 상관성에 의해 미 관측지점의 온실가스 배출량을 신뢰성 있게 추정하기 위해 적합한 베리오그램 모델링을 설정하였다. 이에 교차검증을 통하여 적합한 베리오그램 모델과 크리깅 기법의 타당성을 검증하였다. 셋째, 검증된 크리깅 기법으로 미 관측지점의 도로교통에서 발생한 온실가스 배출량을 예측하여 행정구별로 도로교통 온실가스 배출량을 추정하여 산정하였다. 그 결과, 도로교통 온실가스 배출량을 행정구별로 보면 북구가 약 $291,878,020kgCO_2eq/yr$로 가장 많은 온실가스를 배출하는 것으로 나타났다. This study was intended to reliably predict the traffic green house gas emission in Daegu with the use of spatial statistical technique and calculate the traffic green house gas emission of each administrative district on the basis of the accurately predicted emission. First, with the use of the traffic actually surveyed at a traffic observation point, and traffic green house gas emission was calculated. Secondly, on the basis of the calculation, and with the use of Universal Kriging technique, this researcher set a suitable variogram modeling to accurately and reliably predict the green house gas emission at non-observation point suitable through spatial correlation, and then performed cross validation to prove the validity of the proper variogram modeling and Kriging technique. Thirdly, with the use of the validated kriging technique, traffic green gas emission was visualized, and its distribution features were analyzed to predict and calculate the traffic green house gas emission of each administrative district. As a result, regarding the traffic green house gas emission of each administration, it was found that Bukgu had the highest green house gas emission of $291,878,020kgCO_2eq/yr$.

$Ar/N_2 및 Kr/N_2$혼합가스의 교류절연파괴 특성

이상우,김인식,이동인,이광식,김이국,Lee, Sang-Woo,Kim, In-Sik,Lee, Dong-In,Lee, Kwang-Sik,Kim, Lee-Kook 대한전기학회 2001 전기학회논문지C Vol.50 No.12

In this paper, the ac breakdown characteristics of pure Ar, Kr and $N_2$ gas with gas pressure range of 58.8-137.3[kPa] under uniform and non-uniform fields were investigated, and the measured values were compared with those In Ar/$N_2$ and Kr/$N_2$ gas mixtures with pressure varying. Summarizing the experimental results, the breakdown voltages of Pure $N_2$gas, under uniform and non-uniform fields, were increased about 4.8 and 1.1 times than those of pure Ar gas, and about 4.4 and 1.2 times than those of pure Kr gas, and the ac breakdown voltage increased with the pressure increasing. The breakdown voltages of Ar/$N_2$ gas mixtures were decreased with decreasing the mixture ratio of Pure $N_2$ gas. In case of Ar(85%)/$N_2$ (15%) and Ar(70%)/$N_2$ (30%) gas mixtures comparing to the pure Ar gas, the breakdown voltages under uniform field were increased about 1.8 and 2.2 times, and under non-uniform field were increased about 1.1 and 1.3 times at the pressure of 101.3[kPa]. Also, in case of Kr(85%)/$N_2$ (15%) and Kr(70%)/$N_2$ (30%) gas mixtures comparing to the pure Kr gas, the breakdown voltages under uniform field were increased about 1.7 and 2.0 times, and under non-uniform field were increased about 1.0 and 1.2 times. Corona inception voltage of Kr(70%)/$N_2$(30%) gas mixtures under non-uniform fields were increased about 1.28 times than those of Ar(70%)/$N_2$ (30%) gas mixtures. In case of practical incandescent lamps, luminous and lifetime of Kr(70%)/$N_2$ (30%) gas mixtures were increased about 1.15 and 1.21 times than those of Ar(70%)/$N_2$ (30%) gas mixtures.

물리화학적 처리를 이용한 군부대 사격장 내 중금속 오염 토양의 정화

이상우,이우춘,이상환,김순오,Lee, Sang-Woo,Lee, Woo-Chun,Lee, Sang-Hwan,Kim, Soon-Oh 한국지하수토양환경학회 2021 지하수토양환경 Vol.26 No.5

This study evaluated the feasibility of combined use of physical separation and soil washing to remediate heavy metals (Pb and Cu) contaminated soil in a military shooting range. The soils were classified into two types based on the level of heavy metal concentrations: a higher contaminated soil (HCS) with Pb and Cu concentrations of 6,243 mg/kg and 407 mg/kg, respectively, and a lower contaminated soil (LCS) with their concentrations of 1,658 mg/kg and 232 mg/kg. Pb level in both soils exceeded the regulatory limit (700 mg/kg), and its concentration generally increased with decreasing soil particle size. However, in some cases, Pb concentrations increased with increasing soil particle size, presumably due to the presence of residues of bullets in the soil matrix. As a pretreatment step, a shaking table was used for physical separation of soil to remove bullet residues while fractionating the contaminated soils into different sizes. The most effective separation and fractionation were achieved at vibration velocity of 296 rpm/min, the table slope of 7.0°, and the separating water flow rate of 23 L/min. The efficiency of ensuing soil washing process for LCS was maximized by using 0.5% HCl with the soil:washing solution mixing ratio of 1:3 for 1 hr treatment. On the contrary, HCS was most effectively remediated by using 1.0% HCl with the same soil:solution mixing ratio for 3 hr. This work demonstrated that the combined use of physical separation and soil washing could be a viable option to remediate soils highly contaminated with heavy metals.

천수만 해역에서 장마기 담수 방류가 플랑크톤에 미치는 영향

이상우,박철,이두별,이재광,Lee, Sangwoo,Park, Chul,Lee, Doobyoul,Lee, Jaegwang 한국해양학회 2014 바다 Vol.19 No.1

반폐쇄적인 천수만에서 장마기 동안 짧은 기간에 대량의 담수가 집중적으로 유입될 때 발생할 수 있는 플랑크톤 생태계의 영향을 파악하고자 하였다. 이를 위해 장마기 전 후, 2012년 6월 27일부터 9월 1일까지 약 열흘 간격으로 수온, 염분, chlorophyll a 농도, 영양염 농도와 동물플랑크톤의 분포를 조사하여, 이들 각 변수간의 관계를 파악해 보았다. 담수 방류 후 영양염 농도는 약 2배 이상 증가하였고, 그 결과로 나타나는 chlorophyll a 농도 증가는 수 일이 소요되는 것으로 추정되었다. 동물플랑크톤의 경우는 먹이생물인 식물플랑크톤의 증가에 따른 개체수 증가라는 긍정적인 면과 염분 충격으로 인한 사망이라는 부정적인 면이 동시에 나타나는 것으로 여겨졌다. 급격한 염분 하강으로 인한 동물플랑크톤의 사망률은 최고 40%까지 나타났으나, 사체의 빠른 침강으로 신뢰할 만한 사망률 추정에는 한계가 있었다. The impact of freshwater discharge on plankton was investigated in a semi-closed Cheonsu Bay during the rainy season. Field observations for environmental factors (seawater temperatures, salinities, chlorophyll a concentrations and nutrient concentrations) and zooplankton sampling were carried out from June 27 to September 1, 2012 at about 10 days interval. The relationship between the measured parameters and estimated values of zooplankton abundance were examined. After freshwater discharge, nutrient concentrations increased up to about twice and resultant increase of chlorophyll a followed within about 10 days. Both positive and negative impacts on zooplankton were observed. Positive one was the numerical response of zooplankton on this increased food supply, and negative one was the increased mortality caused by sudden changes in salinity. Maximum mortality of copepods was found to be up to 40%, although fast sinking of carcass made it difficult to estimate reliable mortality caused by salinity shock.

소형 연료전지 연계형 DC GRID 부하 특성

이상우,이상철,권오성,배준형,박태준,강진규,이동하,Lee, Sang-Woo,Lee, Sang-Cheol,Kwon, O-Sung,Bae, Jun-Hyung,Park, Tae-Joon,Kang, Jin-Kyu,Lee, Dong-Ha 한국태양에너지학회 2012 한국태양에너지학회 논문집 Vol.32 No.suppl3

In recent years, understanding the dynamics of DC distribution system has become critically important due mainly to the increasing needs for the interconnection of DC distributed generators and the (DC-based) electric vehicle (EV) charging systems. In this paper, the characteristics of the DC grid system connected to the compact proton exchange membrane fuel cell (PEMFC) has been studied. In particular, the voltage and current transient phenomena were measured by varying the load of the DC grid system. Also, the voltage and current ripple were measured at the different load conditions. Our experimental results clearly manifested that the study contributes to the establishment of fundamental method to characterize the small DC grid system including distributed generation.

반응표면법을 이용한 안전밸브의 최적화

이상우,신대영,변철웅,Lee, Sang-Woo,Shin, Dae-Young,Byun, Cheol-Woong 한국전산구조공학회 2007 한국전산구조공학회논문집 Vol.20 No.5

소화시스템에 사용되는 고압의 소화가스 저장용기에는 저장용기의 파손을 막아주는 안전밸브가 있다. 이러한 안전밸브의 내부에는 원형 박판의 파열 판이 들어 있는데, 저장용기의 내압이 위험수준에 도달하면 파열 판이 파손하여 내압을 배출하는 역할을 한다. 안전밸브의 설계인자는 파열 판의 두께, 안전밸브의 유로 직경, 플라스틱 패킹 링의 내부 직경 그리고 파열 판을 고정하는 볼트 안쪽의 필렛 반경이 있다. 이중에서 파열 판의 두께는 0.2mm로 고정을 하였다. 요인배치법을 사용하여 주효과를 결정하였고 회귀방정식을 유도하였다. 이러한 회귀방정식은 추후 안전밸브의 설계에 있어서 기초 설계 자료로서 활용할 수 있도록 실험 결과와 비교하여 검증하였다. 검증실험 및 회귀방정식에 의한 결과의 오차는 약 $2{\sim}5%$ 정도인 것을 확인하였다. 그리고 반응표면법을 사용하여 기밀테스트 압력인 25MPa에서 파열할 수 있는 안전밸브의 최적 모델을 결정하였다. High pressure storage of the agent gas in fire suppression system was composed of tank, main valve and safety valve, which prevents the fracture of the high pressure storage. The safety valve has circular thin plate as fracture plate that was destroyed over fracture pressure. When inner pressure of the storage is reached the fracture pressure, the safety valve discharges gas and degrades simultaneously the inner pressure of the storage. There are design variables such as flow path diameter, inner diameter of the plastic packing ring, thickness of plate and fillet radius. In this variables, thickness of plate is set to be a value of 0.2mm. The main effect of variables on the inner pressure, has been decided using factorial design and statistical analysis. Therefore, the relation of variables are expressed by regression equation. It is disclosed results that the difference of fracture pressures between the equation and experiment has $2{\sim}5%$. Finally, using response surface method, the optimal design of the safety valve could be decided with safety pressure of 25MPa, where the fracture occurs on circular thin plate.

체계적 지역연구의 꿈-서강대 동아연구소의 연구설계

이상우,Lee, Sang-U 한국대학교육협의회 1985 大學敎育 Vol.16 No.-

군 소화기 사격장 소음측정 및 소음저감 방안 평가

이상우,김희석,정상조,Lee, Sang-Woo,Kim, Hee-Seok,Jeong, Sang-Jo 한국군사과학기술학회 2009 한국군사과학기술학회지 Vol.12 No.1

Civil petitions and law suits against the military rifle shooting noise have been increased because many military shooting ranges are located near civilian residential area. In order to solve the noise problems, military have devised various methods. In this study, propagation properties of rifle shot through atmosphere were investigated. The military rifle shooting noise level at 5m from muzzle was between $l14{\sim}120dB$ in all directions. The noise level loom both backward and sideward away from system firing range consisting lines of 8 shooting locations were 90dB, when shots were all fired within 10 seconds. At present some of military bases established sound barriers, muzzle enclosures, silencers, and indoor shooting ranges to reduce noises and these prevention methods can reduce noise by $5{\sim}20dB,\;5{\sim}9dB,\;5{\sim}13dB,\;40{\sim}50dB$, respectively. Even though indoor shooting range has the best performance, it requires very expensive construction cost and has short length between target and shooter. In comparison, muzzle enclosure is cheap, but because it is installed in fixed position it can only be used in one shooting position. Therefore a commander should select appropriate methods to reduce military rifle shooting noise considering distance from residential area to the range, mission of military training, budget, etc.

폭방향으로 분사되는 막냉각 제트의 3차원 유동특성 및 압력손실

이상우,김용범,Lee, Sang-U,Kim,Yong-Beom 대한기계학회 1996 大韓機械學會論文集B Vol.20 No.4

Oil-film flow visualizations and three-dimensional flow measurements using a five-hole probe have been conducted to investigate three-dimensional flow characteristics and total pressure losses of a row of film-cooling jets injected in spanwise direction. For several span-to-diameter ratios, experiments are performed in the case of three velocity ratios of 0.5, 1.0 and 1.5. The flow measurements show that downstream flow due to the injection is characterized by a single streamwise vortex instead of a pair of counter-rotating vortices, which appear in the case of streamwise injection, and the vortex strength strongly depends on the velocity ratio. Regardless of the velocity*y ratio, presence of the spanwise film-cooling jets always produces total pressure loss, which is pronounced when the velocity ratio is large. It has also been found that the production of the total pressure loss is closely related to the secondary vortical flow. In addition, effects of the span-to-diameter ratio on the flow and total pressure loss are discussed in detail.

원산지규정 분석을 통한 수출 중고품에 대한 FTA 특혜관세 활용방안

이상우,이춘수,Sang-Woo Lee,Chun-Su Lee 한국국제상학회 2015 國際商學 Vol.30 No.2

오늘날 무역거래의 대상은 대부분 신품인 경우가 많으나, 최근 물품의 내구성이 증대되 면서 중고차량, 중고기계 등 중고품의 무역거래량도 점차 늘어나고 있는 추세를 보이고 있 다. 이에 중고품에 대한 FTA 특혜관세 활용방안 및 법적 근거에 대한 검토가 필요하다. 그 러나 중고품의 경우 기존 FTA 협정에서 관련 규정이 거의 없기 때문에 중고품이 FTA 특혜 관세의 대상이 될 수 있는지의 여부, 중고품에 대한 원산지판정 방법 등의 문제를 논하는 데에 한계가 있다. 본 연구는 수출 중고품의 FTA 활용현황과 활용상의 문제점을 파악하고, FTA 협정문에 서 규정하고 있는 중고품 관련 원산지규정분석을 통해 중고품의 FTA 특혜관세활용방안을 모색하는데 연구목적을 두고 있다. 특히, 중고품관련 원산지규정 분석을 각 국가별 체결협정 대상으로 검토하기 위해서 중고품의 FTA 특혜관세 적용 가능성 파악을 위한 FTA 협정 상 관련 규정에 대한 검토, 원산지결정기준의 충족 여부에 대한 검토 그리고 신품의 원산지 지위의 중고품 승계문제를 다루고 중고품 수출시 특혜관세 활용방안을 위해 시스템구축 사례를 제시한다. The objective of this study is to grasp the FTA utilization status for used goods that are exported and the problems related to utilization, and to grope for a plan to utilize the FTA preferential tariffs by analyzing rules of origin specified in FTAs in relation to used goods. This study performed a literature review utilizing secondary sources and interview. For used goods, as there are almost no related provisions in the existing FTAs, there are limitations in discussing issues such as whether used goods can be an object of an FTA preferential tariff or not, and the method to determine the county of origin of used goods. Accordingly, cooperation from original manufactures is required for utilization of the FTA preferential tariff on used goods, and a plan to institutionalize such a part should be arranged. Also, rules of origin for used goods is required to be separately specified to allow easier application differently from that of new goods considering the present situation where utilization is practically difficult.