하천변 지하수 양수로 인한 하천수 감소 영향의 공간적 평가 - 죽산천 유역을 중심으로 -

이정우,김남원,정일문,이민호,Lee, Jeongwoo,Kim, Nam Won,Chung, Il Moon,Lee, Min Ho 한국수자원학회 2015 한국수자원학회논문집 Vol.48 No.7

본 연구에서는 죽산천 주변 지역에 대해 지하수 양수에 따른 하천수 감소 영향을 공간적으로 분석하였다. 하천 주변 500 m 이내에 위치한 지하수 관정 각각에 대해 지표수-지하수 결합모형 SWAT-MODFLOW를 이용하여 양수 후 하천수 감소량을 반복적으로 모의하였다. 모의 결과, 양수량 대비 하천수 감소율이 20~96%의 범위로 큰 차이를 보였으며, 특히, 하천과 관정간 이격거리가 100 m 이내, 수리확산 계수가 $500m^2/d$ 초과, 하천바닥층 수리전도성이 25 m/d를 초과한 경우에 양수량 대비 하천수 감소율이 60%를 넘어 양수 영향이 큰 것으로 분석되었다. 지하수 관정의 공간적인 위치에 따른 하천수 감소 영향을 정량적으로 쉽게 파악할 수 있도록 관정 위치별 하천수 감소량을 양수량 대비 퍼센트 값을 가지는 등치선 곡선으로 나타내었다. 죽산천 중하류구간 주변지역이 상류지역에 비해 지하수 양수로 인한 영향이 단기간에 크게 하천에 도달하였으며, 양수기간 5년 동안 평균적으로 약 66.7%의 하천수 감소율이 발생하는 것으로 분석되었다. 하천수량에 미치는 지하수 양수 영향을 공간적으로 표출함으로써 하천변 지하수 허가 관리에 있어 객관적인 정보로 활용할 수 있을 것이다. The objective of this study is to spatially assess the streamflow depletion due to groundwater pumping near the main stream of Juksanchoen watershed. The surface water and groundwater integrated model, SWAT-MODFLOW, in this study, was used to simulate streamflow responses to each groundwater pumping from wells located within 500m from the stream. The simulated results showed that the streamflow depletion rate divided by the pumping rate for each well location ranges from 20% to 96%. In particular, the streamflow depletion exceeds 60% of pumping rate if the distance between stream and well is lower than 100 m, hydraulic diffusivity is higher than $500m^2/d$, and streambed hydraulic conductance is above 25m/d. The simulated results were also presented in the form of spatial distribution maps that indicate the fraction of the well pumping rate in order to show the effect of a single well more comprehensively and easily. From the developed areal distribution of stream depletion, higher and more rapid responses to pumping occur near middle-downstream reach, and the spatially averaged percent depletion is about 66.7% for five years of pumping. The streamflow depletion map can provide objective information for the near-stream groundwater permission and management.

안성천 상류유역 하천유량에 미치는 농업용 저수지와 지하수 이용 영향 분석

이정우,김남원,정일문,이정은,Lee, Jeongwoo,Kim, Nam Won,Chung, Il-Moon,Lee, Jeong Eun 대한토목학회 2015 대한토목학회논문집 Vol.35 No.4

본 연구에서는 안성천 공도수위관측소 상류유역에 대해 지표수-지하수 통합모형 SWAT-MODFLOW를 적용하여 농업용 저수지 관개 및 지하수 이용에 따른 하천유출량 변화를 모의하였다. 유역내에 위치한 고삼 및 금광 저수지 직하류부에서는 관개용수 공급으로 인하여 갈수량이 자연 유량 조건에 비해 각각 약 31.2%, 82.5% 만큼 감소하는 것으로 분석되었다. 반면에 유역 출구부에서는 회귀수 영향으로 농업용 저수지 영향이 작게 나타나 5.7% 정도의 갈수량이 감소하였으며, 지하수 양수 영향과의 복합적 영향으로 약 19.2% 만큼 감소하는 것으로 분석되었다. Streamflow responses to irrigation reservoirs and groundwater withdrawals were simulated using the integrated surface-water and groundwater model, SWAT-MODFLOW for the upstream watershed of the Gongdo station located in the Anseong stream. The simulated results indicated that the irrigation water supply from the Gosam and the Geumkwang reservoirs has caused the decrease of 31.2%, 82.5% in drought flows below the reservoirs, respectively, against the natural flow condition. While, at the outlet of the study watershed, the effects of the irrigation reservoirs were insignificant due to the delayed return flows with the decrease of 5.7% in drought flow. Both of the irrigation reservoirs and groundwater withdrawals have reduced the drought flows by 19.2% at the Gongdo station.

미세전류 특정 주파수와 적용시기에 따른 지연성근육통 유발로 인한 근육의 기계적 특성변화

이정우,이슬,두영택,Lee, Jeongwoo,Lee, Seul,Doo, Yeongtaek 대한통합의학회 2019 대한통합의학회지 Vol.7 No.2

Purpose : The purpose of this study was to determine the effects of specific frequency and application timing of microcurrent (MC) on the mechanical property of muscle caused by delayed onset muscle soreness (DOMS). Methods : The subjects were 32 healthy adults with 8 subjects randomly assigned to four groups (I; 40 Hz MC while inducing DOMS, II; 40 Hz MC immediately after inducing DOMS, III; 284 Hz MC while inducing DOMS, IV; 284 Hz MC immediately after inducing DOMS). DOMS is applied to the biceps brachii muscle while MC was applied at an intensity of $300{\mu}A$ for 10 minutes. The mechanical properties of muscle were measured before and immediately after DOMS. Results : In terms of muscle tone, there were significant differences in interaction effects between time and groups. Regarding muscle elasticity and stiffness, there were no significant differences in interaction effects between time and groups but there were only significant differences in main effects based on time. Conclusion : The results indicated that 40 Hz MC had an effect on reducing muscle tone regardless of application timing. However, both 40 Hz and 284 Hz MC did not trigger changes in muscle elasticity and stiffness regardless of application timing.

죽산천 주변 암반층 지하수 양수로 인한 하천수 감소 영향 분석

이정우,김남원,정일문,차준호,Lee, Jeongwoo,Kim, Nam Won,Chung, Il Moon,Cha, Joon Ho 한국수자원학회 2015 한국수자원학회논문집 Vol.48 No.9

본 연구에서는 죽산천 주변 지역에 대해 SWAT-MODFLOW 결합모형으로 암반층 지하수 양수에 따른 하천수 감소량을 모의하여 하천-관정 이격거리, 대수층 및 하천바닥층 수리특성 등과의 관계를 파악하고, 양수 위치에 따른 하천수 감소량을 공간적으로 표출하여 그 특징을 분석하였다. 양수정 위치에 따른 하천과의 이격거리, 투수량계수, 저류계수, 하천바닥층 수리전도성 등의 차이로 인해 지하수 양수량 대비 하천수 감소량 비율이 10~90%의 범위를 나타내었으며, 투수량계수가 $10m^2/day$ 보다 크거나 저류계수가 0.1보다 작은 경우 대부분 관정에서 하천수 감소율이 50%를 초과하는 것으로 분석되었다. 암반층에서 지하수를 양수할 경우 5년 동안 평균적으로 53.6%의 하천수 감소율을 나타내어 충적층 양수에 비해 12.9% 만큼 덜 감소하는 것으로 분석되었다. 또한 죽산천 중하류부에서 양수 영향이 비교적 크게 나타나는 것으로 분석되었다. The streamflow depletion due to groundwater pumping from deep aquifer near the Juksan stream has been simulated, in this study, by using the surface water and groundwater integrated model, SWAT-ODFLOW in order to analyze the relationship between the stream depletion and hydraulic properties of aquifer and streambed, and to spatially assess the streamflow depletion. The simulated results showed that the streamflow depletion rate divided by the pumping rate for each well location ranges from 10% to 90% with reflecting the various well-stream distance, transmissivity, storativity, and streambed hydraulic conductance. In particular, the streamflow depletion exceeds about 50% of pumping rate for conditions with transmissivity higher than $10m^2/day$ or storage coefficient lower than 0.1. The simulated results in the form of spatial maps indicated that the spatially averaged percent depletion of streamflow is about 53.6% for five years of pumping which is lower than that for shallow aquifer pumping by 12.9%. From the spatially distributed stream depletion, it was found that higher and more rapid stream depletion to pumping occurs near middle-downstream reach.

소아에서 수술 후 발생한 장폐색에 대한 복강경 유착박리술의 초기 경험

이정우,정은영,박우현,최순옥,Lee, Jeongwoo,Jung, Eunyoung,Park, Woo-Hyun,Choi, Soon-Ok 대한소아외과학회 2013 소아외과 Vol.19 No.1

The purpose of this study is to analyze the early experience of the laparoscopic adhesiolysis for the intestinal obstruction due to postoperative adhesion. Seven patients were included in this study. The median age of those patients was 13, and there were 3 males and 4 females. Previous diagnosis and surgical procedure were various in seven cases, including small bowel resection with tapering enteroplasty, Boix-Ochoa fundoplication, Ladd's procedure with appendectomy, mesenteric tumor resection with small bowel anastomosis, ileocecal resection and anastomosis, primary gastric repair, and both high ligation. A successful laparoscopic adhesiolysis was performed in one who had high ligation for inguinal hernia and had a single band adhesion. Six out of 7 (86%) cases needed to convert open surgery due to multiple and dense type of adhesion. In conclusion, laparoscopic approach with postoperative small bowel adhesion seems safe. However, it might be prudently considered because of high rates of conversion in children.

승용디젤 엔진에서 JP-8 연료 적용 시 다단분사를 이용한 배기저감 방법 연구

이정우(Jeongwoo Lee),주상현(Sanghyun Chu),이정연(Jungyeon Lee),이승현(Seunghyun Lee),이윤우(Yoonwoo Lee),이성문(Sungmoon Lee),최회명(Hoimyung Choi),민경덕(Kyungdoug Min) 한국자동차공학회 2014 한국자동차공학회 부문종합 학술대회 Vol.2014 No.5

As a statement of EURO-6 regulation, NOx emission should be reduced as a half of current standard from September, 2014. For the reduction of NOx emission, EGR is the most effective method due to thermal and diluted effects. However, since there is a trade-off relation between NOx and PM emissions, using heavy EGR rate stimulates the increment of PM emission. For this reason, many of Diesel engine have equipped DPF to eliminate PM emission, but it brings the deterioration of fuel consumption. JP-8 could be a good approach to reduce PM emission from Diesel engine. Since cetane number of JP-8 is lower than that of Diesel, ignition delay becomes prolonged. Also, premixed condition between air and fuels could be improved, because distillation temperature of JP-8 is lower than that of Diesel. These two characteristics effect on the reduction of PM emission. However, in previous researches, phenomenon of NOx increment was observed by JP-8 fueled combustion because of prolonged ignition delay. Thus, in this research, reduction of NOx and PM emissions simultaneously is studied by using multiple injection strategy constructing with pilot injections. The result shows low PM emission could be obtained while there is no penalties on NOx emission.

자기식 회전 엔코더의 정밀도에 관한 실험적 연구

이정우(Jeongwoo Lee),파우델 툴시(Tulsi Paudel) 대한기계학회 2015 대한기계학회 춘추학술대회 Vol.춘계 No.-

북한인권 문제에 대한 쟁점과 해법

이정우(Lee JeongWoo) 한국정치정보학회 2011 정치정보연구 Vol.14 No.2

이 글에서는 북한인권 쟁점과 해법이라는 제목으로 인권개선과 국제사회의 개입, 북한인권에 관한 쟁점사항별 분석 그리고 북한인권 개선을 위한 나름대로의 해법을 모색해 보았다. 그러나 안타깝게도 북한인권 상황을 획기적으로 개선시키기 위한 방법론적 해법은 모색되지 못하였다. 다만 북한인권의 개선을 위해서는 한국정부와 민간단체의 끊임없는 대화와 역할 분담 그리고 국제사회와의 공조라는 도식적인 결론을 내릴 수밖에 없는 상황이다. 이러한 결론이 불가피한 것은 북한인권의 개선을 위해서는 다양한 분야에서 포괄적이고 적극적인 노력이 필요하고 최종적으로 북한이 이를 수용할 수 있는 체제안정성의 여유가 생겨야 하기 때문이다. 북핵문제가 해결되지 않고 한반도를 둘러싼 안보적 먹구름속에서 걷히지 않는 상황에서 북한인권 문제는 아무리 개별적으로 접근하려고 해도 그것을 수용하는 쪽이나 지원하는 쪽이나 여러 정치적 고려와 선택을 하지 않을 수 없다. 따라서 이 글에서 살펴 본 쟁점들 모두는 인권상황 자체의 문제가 아니고 현재의 남북관계 상황을 전체적으로 반영하는 것이다. 북한 인권문제는 통일이후 사회통합 과정에서 지대한 영향을 미칠 수 있기 때문에 적극적인 대책이 요구된다. 그러나 북한인권 문제는 개별적 접근으로 해소될 수 있는 사안이 아닌 것도 사실이다. 그러나 이런 이유로 북한인권 문제를 방치할 수 없는 것도 우리의 입장이다. 인권에 대한 문제의 제기만으로도 장기적 차원에서는 북한의 인권개선 및 민주화에 도움을 줄 수 있을 것이기 때문이다. This paper examines how to improve North Korea’s human rights through intervention by international society including South Korea. But I could not find a clear solution methodologically, but there is only way in which South Korean government and civil group should co-work with international society through continuous dialogues and role-sharing. The important thing to improve North Korea’s human rights is the stability of North Korean regime. Thus, there should be lots of political considerations before North Korea’s nuclear crisis ends because North Korean government always thinks of its own regime stability. Therefore, the problem of North Korea’s human rights is not only human rights issue but also reflection of current North Korean politics and inter-Korean situation. Positive and active countermeasures must be needed when we think of North Korea’s human rights problem because it will affect much to social integration even in unified Korea. So, we have no way to avoid North Korea’s human rights problem strategically. It is helpful to improve human rights and democratization of North Korea when we raise issue about it from a long-term perspective.

부산다행복학교 초등학생 학업성취수준 분석

이정우 ( Lee Jeongwoo ),김혜영 ( Kim Hyeyoung ),김동선 ( Kim Dongsun ),한유경 ( Han Youkyoung ),홍창남 ( Hong Changnam ) 한국초등교육학회 2020 초등교육연구 Vol.33 No.1

본 연구는 부산교육종단연구 1차∼3차 자료를 활용하여, 부산형 혁신학교인 부산다행복학교 초등학생의 국어·영어·수학 학업성취수준을 일반학교와 비교 분석하였다. 구체적으로, 학업성취수준 격차 분석을 위하여 기술통계를, 학업성취 수준 초기치(시작점)와 성장률 분석을 위하여 선형다층성장모형을 각각 활용하였다. 또한 부모 학력수준(고졸 이하와 4년제 졸 이상)에 따른 학업성취 격차를 동일하게 다행복학교와 일반학교를 비교분석하였다. 분석결과, 다행복학교의 학업성취수준은 세 교과에서 모두 일반학교보다 매년 낮지만, 향상도는 더 높은 수준을 보였다. 성장모형 분석에서도 일반학교의 높은 초기치, 그러나 다행복학교의 높은 성장률이라는 동일한 결과가 나타났다. 부모 학력별 차이의 경우, 학교 유형과 상관없이 고졸 이하 표본은 4년제 졸 이상 표본보다 모든 교과에서 낮은 초기치를 보였다. 그러나 성장률의 경우, 고졸 이하 부모를 둔 다행복학교 학생들이 국어와 수학 교과에서 일반학교의 동일 집단보다 더 높은 성장률을 보였다. 이러한 결과는 다행복학교가 부산 지역에서 학교혁신 모델로서의 지속가능성과 필요성을 보여준다는 점에서 의의가 있다. This article empirically explored the academic achievement in Korean, English, Mathematics of elementary school students enrolled in Busan innovation school called Dahangbok Schools, using the first three waves(2016∼2018) of the Busan Educational Longitudinal Study. Specifically, descriptive statistics were used to present the academic achievement in terms of the achievement gap over time and the degree of improvement, and multi-level linear growth modeling to analyze the initial level of academic achievement and the rate of growth in academic achievement. Also, this article analyzed the academic achievement by parental education (secondary education or lower vs. 4-year college degree or higher) in the context of educational equity. The results indicate that the academic achievement of students enrolled in the Dahangbok Schools was, on average, lower than those of students enrolled in general schools in all the subjects each year. However, the Dahangbok Schools showed a higher degree of improvement in the academic performance. The analysis of multi-level linear growth modeling confirmed these findings. Academic achievement’s initial level appeared to be higher for general schools, but the rate of growth higher for the Dahangbok Schools. On the other hand, students with parents with secondary education or lower showed a lower initial level of academic achievement than those with 4-year college degree or higher in all the subjects regardless of type of school. However, students with parents with secondary education or lower enrolled in the Dahangbok Schools showed the highest growth rate in Korean and Mathematics.

염증성 근육뼈대계 질환에 대한 미세전류의 효과: 메타분석

이정우 ( Lee Jeongwoo ),고운 ( Ko Un ),두영택 ( Doo Yeongtaek ) 대한통합의학회 2020 대한통합의학회지 Vol.8 No.4

Purpose : The purpose of this meta-analysis was to examine the effects of microcurrent on inflammatory musculoskeletal diseases. Methods : Domestic databases (RISS, NDSL, KISS, DBpia, and Kmbase) were searched for studies that conducted clinical trials associated with microcurrent and its impact on inflammatory musculoskeletal diseases. A total of 606 studies published between 2002 and 2019 were identified, with 8 studies satisfying the inclusion data. The studies were classified according to patient, intervention, comparison, and outcome (PICO). The search outcomes were items associated with blood component, pain, and function. The 8 studies that were included in the study were evaluated using R meta-analysis (version 4.0). The quality of 7 randomized control trials was evaluated using Cochrane risk of bias (ROB). The quality of 1 non-randomized control trial was evaluated using risk of bias assessment tool for non-randomized studies (RoBANS). Effect sizes were computed as the corrected standard mean difference (SMD). A random-effect model was used to analyze the effect size because of the high heterogeneity among the studies. Egger’s regression test was carried out to analyze the publishing bias. Results : The following factors had a large effect size involving microcurrent on inflammatory musculoskeletal diseases: blood component (Hedges’s g=-2.46, 95 % CI=-4.20~-0.73), pain (Hedges’s g=3.51, 95 % CI=2.44~4.77), and function (Hedges’s g=3.06, 95 % CI: 1.53~4.58). Except for function (t=1.572, p=.191), Egger’s regression test showed that the publishing bias had statistically significant differences. Conclusion : This study provides evidence for the effectiveness of microcurrent on inflammatory musculoskeletal diseases in terms of blood component, pain, and function. However, due to the small sample sizes used in the included studies, the results of our study should be interpreted cautiously, especially considering the publishing bias.