SNL-EFDC를 이용한 군산항 유사퇴적고 계산의 비교 연구

이동주 ( Dong-joo Lee ),송상현 ( Sang-hyun Song ) 한국환경기술학회 2015 한국환경기술학회지 Vol.16 No.4

본 논문은 Ziegler, Lick, and Jones에 의해 개발된 SEDZLJ라 부르는 유사역학 알고리즘이 계산되는 SNL-EFDC 모델을 이용하여 군산항의 퇴적고 계산에 관하여 연구하였다. SEDZLJ모듈은 SEDflume 이나 Annular flumes로부터 얻은 현장 침식률 및 침식 한계전단응력 자료를 직접 결합할 필요가 있다. 군산항에서는 SEDflume 자료를 구할 수 없기 때문에 Ryu와 Yim에 의한 Annular flumes 실험으로부터 얻은 현장 침식률 및 침식 한계전단응력 자료를 이용하였다. SNL-EFDC 모델이 군산항의 유사퇴적고를 계산하기 위해 적용되었고 관측된 부유사 농도와 퇴적고를 사용하여 검증되었다. 유사 퇴적고 계산에 대한 모델의 적용성은 NSEC가 0.72로 침식과 퇴적의 물리적 변화가 적절하게 재현됨이 입증되었다. 부가적으로 검증된 모델은 저면 활성층두께에 대한 매개변수 α값의 영향을 조사하기 위해 사용되었고, Lee와 Park에 의해 수행된 SEDTM을 이용한 유사이동 계산의 결과와 비교하기 위해 사용되었다. 그 결과, 매개변수 α값의 변화는 유사퇴적고 계산에 미미한 영향이 미치는 것으로 나타났다. SEDZLJ에 의한 결과를 SEDTM의 것과 비교할 때 SEDZLJ모듈이 군산항에서 SEDTM 보다 NSEC가 0.03향상 되어 토사이송 과정을 재현함이 확인되었다. This paper was studied on the sediment deposition height computation at Gunsan port using recently advanced SNL-EFDC model which the sediment dynamics algorithm was called as SEDZLJ developed by Ziegler, Lick and Jones. SEDZLJ module needs to directly incorporate site-specific erosion rate and critical shear stress data from SEDflume or Annularflumes. Here this model attempted to use site-specific erosion rate and critical shear stress data from Annular flumes experiment by Ryu and Yim instead of unavailable SEDflume data at Gunsan port. SNL-EFDC was applicated to calculate deposition height at Gunsan port and verified using observed values for suspended sediment concentration and sediment deposition height. The model applicability for sediment deposition height computation was evaluated as NSEC 0.72 and verified that it reproduced the physical variations of erosion and deposition. In addition, the verified model was used to investigate the effect of parameter “α” on the active bed layer thickness and used to compare with the result of sediment transport computation using SEDTM done by Lee and Park. As a result, it was found that the change of parameter “α” value has a negligible effect on sediment deposition height computation. As results of SEDZLJ are compared with those of SEDTM, it was identified that SEDZLJ module reproduces the sediment transport process more appropriately than SEDTM at Gunsan port with advanced NSEC 0.03.

2000년 정유업계 동향

이동주,Lee, Dong-Ju 대한석유협회 2001 석유와 에너지 Vol.2001 No.9

학술정담 공재 (恭齋) 윤두서의 (尹斗緖) 회화

이동주,최순우,안휘준 ( Dong Ju Lee,Soon Woo Choi,Hwi Jun Ahn ) 일지사 1979 韓國學報 Vol.5 No.4

Factors Influencing Learning Satisfaction of Migrant Workers in Korea with E-learning-Based Occupational Safety and Health Education

이동주,Young Joo Lee 한국산업안전보건공단 산업안전보건연구원 2015 Safety and health at work Vol.6 No.3

Background: E-learning-based programs have recently been introduced to the occupational safety and health (OSH) education for migrant workers in Korea. The purpose of this study was to investigate how the factors related to migrant workers’ backgrounds and the instructional design affect the migrant workers’ satisfaction with e-learning-based OSH education. Methods: The data were collected from the surveys of 300 migrant workers who had participated in an OSH education program. Independent sample t test and one-way analysis of variance were conducted to examine differences in the degree of learning satisfaction using background variables. In addition, correlation analysis and multiple regression analysis were conducted to examine relationships between the instructional design variables and the degree of learning satisfaction. Results: There was no significant difference in the degree of learning satisfaction by gender, age, level of education, number of employees, or type of occupation, except for nationality. Among the instructional design variables, “learning content” (b ¼ 0.344, p < 0.001) affected the degree of learning satisfaction most significantly, followed by “motivation to learn” (b ¼ 0.293, p < 0.001), “interactions with learners and instructors” (b ¼ 0.149, p < 0.01), and “previous experience related to e-learning” (b ¼ 0.095, p < 0.05). “Learning environment” had no significant influence on the degree of learning satisfaction. Conclusion: E-learning-based OSH education for migrant workers may be an effective way to increase their safety knowledge and behavior if the accuracy, credibility, and novelty of learning content; strategies to promote learners’ motivation to learn; and interactions with learners and instructors are systematically applied during the development and implementation of e-learning programs.

호우 형태에 따른 호우중심형 면적감소계수 비교

이동주,현석훈,강부식,Lee, Dongjoo,Hyun, Sukhoon,Kang, Boosik 대한토목학회 2015 대한토목학회논문집 Vol.35 No.6

The Fixed Area ARFs (Area Reduction Factors) method has limitations in providing exact information about spatial distribution due to the lack of enough density of rain gauge stations. In this study the storm-centered ARF was evaluated between frontal and typhoon storm events utilizing radar precipitation. In estimating storm-centered ARFs, in order to consider the horizontal advection, direction, and spatial distribution of rain cells, the rotational angle of rainfall of each rainfall event and the optimum areal rainfall within the spatial rain cell envelope was taken into account. Compared with the frontal storm, the ARF of typhoon storm shows narrow range of variability. It is noted that the ARFs of frontal storm increases with the rainfall duration, but those of typhoon storm shows opposite pattern. As a result the typhoon ARFs appear greater than frontal ARFs for 1~3 hours of duration, but less for more than 6 hours of duration. 면적고정형 ARF (Fixed Area ARFs)방법은 강우관측소의 지점강우를 활용하여 산정되고 있으며, 공간적 관측밀도의 제약이 정확한 ARF산정에 제약조건이 되고 있다. 본 연구에서는 레이더 강우관측을 활용하여 호우중심형의 ARF를 제시하고자 한다. 호우중심형 ARF (Storm-centered ARFs)산정 시 강우의 이동성, 방향성, 공간분포를 고려하기 위하여 강우사상별 강우형상에 따른 타원 장축의 방향성 결정, 강우형상에 따른 면적별 최적면적강우량을 산정하여 ARF를 제시하였다. 전선형에 비하여 태풍의 ARF값의 변동 폭이 작은 것을 알 수 있었고, 전선형은 지속시간에 따라 ARF가 증가하지만, 태풍의 경우에는 오히려 ARF가 감소하는 모습을 볼 수 있었다. 이 결과 지속시간이 비교적 짧은 1~3시간에서는 태풍 산바 사상의 ARF가 크게 산정되었으나, 지속시간이 긴 6~24시간에서는 ARF가 전선형 강우에 비해 작게 산정됨을 확인하였다.

구강내과 내원환자에 관한 역학조사 -충남지역에 대한-

이동주,김기석,Lee, Dong-Ju,Kim, Ki-Suk 대한안면통증구강내과학회 2006 Journal of Oral Medicine and Pain Vol.31 No.1

Temporomandibular disorders (TMD) is a collective term embrassing a number of clinical problems that involve the masticatory musculature, the Temporomandibular joint and associated structures, or both. The prevalence of signs and symptoms associated with TMD can be best appreciated by examining epidemiologic studies. But domestic epidemiologic studies about sex, history, chief complaint, diagnosis were not sufficient comparing with foreign countries. The results obtained as follow. 1. The number of visiting patients were 6500 and mean age was 34.06 year (Male's mean age was 33.15, Female's 34.62). In the age of patients, there was no significant difference between sex. 2. There are most patients who were referred by dentist (80.07%). Most diagnostic group was arthrogenous TMD group and followed by myogenous TMD, soft tissue disease. 3. There was strong interaction between diagnostic groups and chief complaint. 4. There was little pain difference between right and left sides. Male mainly had pain onset under 6 month, but female had pain onset more than 6 month. 5. The number of patients who had joint sound history were 3445 (53.15%). There was no significant difference of pain onset between sex. Clicking sound was most among joint sounds which happened to patients. 6. In analyzing the parafunctional habit, male mainly had bruxism, but female had clenching habit.

지중 열교환기용 시멘트 그라우트에 관한 연구

이동주,백환조,김경만,Lee, Dong-Ju,Baek, Hwan-Jo,Kim, Gyoung-Man 강원대학교 산업기술연구소 2011 産業技術硏究 Vol.31 No.2

In this paper, the applicability of cement grout has been studied as an alternative to bentonite grout for backfill ground heat exchangers. To provide an optimal mixture design, the thermal conductivity of cement grout and bentonite grout with various mixture ratios were experimentally evaluated and compared. Numerical analyses using Fluent(FVM program) were applied to compare the thermal transfer efficiency of the cement grout with that of the bentonite grout used in the construction. Also the effective ground thermal conductivity was measured by In-situ thermal response test. The results showed that the thermal efficiency of the cement grout was better than the bentonite grout. Consequently, the cement grout could be an alternative with more thermal efficiency to bentonite grout for ground heat exchangers.

미국(美國)의 고분자공업(高分子工業)

이동주,Lee, Dong-Ju 韓國고무學會 1966 엘라스토머 및 콤포지트 Vol. No.

광산수의 탈염을 위한 축전식 탈염기술의 적용

이동주,강문성,이상호,박진수,Lee, Dong-Ju,Kang, Moon-Sung,Lee, Sang-Ho,Park, Jin-Soo 한국전기화학회 2014 한국전기화학회지 Vol.17 No.1

본 연구에서 광산수의 재활용을 위해 축전식 탈염공정을 적용하였다. 이를 위해 이온교환폴리머를 코팅한 탄소 전극을 활용하였는데 본 성능을 관찰하기 위해 이온교환폴리머를 코팅하지 않은 탄소 전극으로 광산수의 탈염 운전을 수행하고 비교분석하였다. 또한, 광산수의 높은 농도가 축전식 탈염공정에 미치는 영향을 조사하기 위해 저농도의 기수(NaCl 200 ppm)를 활용한 운전 성능 비교 역시 수행하였다. 연구 결과 이온교환폴리머를 코팅한 탄소 전극을 활용한 광산수 탈염 효율 및 제거양 모두 그렇지 않은 전극에 비해 높았고 에너지 소모량은 더 적게 나타났다. 이는 높은 비패러데이 전류, 높은 염농도에 따른 낮은 용액 저항, 전극 기공 내에서의 이중층 중첩효과에 기인하는 것으로 판단되었다. 또한, 이온교환폴리머를 코팅한 전극을 활용한 기수 탈염 운전 결과 낮은 염농도에 따라 용액의 저항이 높아지고, 제거 대상의 염의 양이 낮아 광산수에 비해 매우 높은 효율을 보였으나, 제거양은 매우 낮음을 알 수 있었다. In this study, capacitive deionization (CDI) was introduced for desalination of mining water. Ion-exchange polymer coated carbon electrodes (IEE) were used in CDI to desalt mining water. The CDI performance using the IEE for desalination of mining water was carried out and then was compared with that using general carbon electrodes without ion-exchange polymer coating (GE). Moreover, to investigate the effect of the concentration of influent solutions on CDI performance, the CDI performance using the IEE for desalination of brackish water (NaCl 200 ppm) was also performed and analyzed. As a result, the higher salt removal efficiency, rate and the lower energy consumption in the CDI process using the IEE and mining water were obtained compared with those using the GE and mining water. It is mainly due to higher non-Faradaic current, low ohmic resistance of the influent, overlapping effect of electric double layers in micropore of the electrode. In addition, the CDI process using the IEE and brackish water shows much higher salt removal efficiency and lower salt removal rate than that using the IEE and mining water. This results from the lower concentration (i.e., higher ohmic resistance) and salt amount of the influent.

관절경 수술시 슬관절내 온도변화

이동주,김형수,박승림,강준순,염승훈,김신,Lee Tong Joo,Kim Hyoung Soo,Park Seung Rim,Kang Joon Soon,Yeoum Seung Hoon,Kim Shin 대한관절경학회 2002 대한관절경학회지 Vol.6 No.1

Purpose : To document the change in the temperature of the knee joint at the initiation and conclusion of an arthroscopic procedure and correlate this temperature change with other intra-operative variables. Material and Methods : Temperature measurements were performed in 40 consecutive patients(42 cases) that underwent arthroscopic surgery. Temperature measurements were taken at the initiation of the procedure, before and after inflation of the tourniquet. The last measurement was recorded at the end of the surgical procedure. Results : The mean knee joint temperature evaluated before inflation of the torniquet was $35.1{\pm}1.0$, at the end of surgery, $24.6{\pm}1.5^{\circ}C$. The mean temperature change observed from the beginning to the end of the procedure was $10.5^{\circ}C$. The student t test showed a statistically significant difference of the initial joint temperature(p<0.01) between the patient with no and+1 effusion / between the patient with no and +2 effusion. The temperature at the end of the procedure was found to be statistically low correlated (p<0.01) with the lower temperature of the irrigant and the lengthening of the arthroscopic procedure. Conclusion : Consideration should be given to maintaining the saline irrigant to more physiologic temperature to protect the articular cartilage from any possible temperature induced damages. 목적 : 관절경 수술 전,후에 발생되는 관절내 온도 변화를 측정하고, 이러한 온도 변화에 영향을 줄 수 있는 요인을 분석하고자 한다. 대상 및 방법 : 반월상 연골의 손상과 전방 십자 인대 손상으로 관절경 수술이 시행된 연속된 40명의 환자를 대상으로 42예의 슬관절에서 온도 변화가 측정되었다. 슬관절 온도의 측정은 3차례에 걸쳐 실시되었는데, 술 전 지혈대 팽창 전, 지혈대를 팽창시킨 후 그리고 마지막 측정은 수술이 끝난 후에 실시하였다. 결과 : 지혈대 팽창 이전의 슬관절 평균 온도는 $35.1{\pm}1.0^{\circ}C$이었고, 술 후 슬관절 온도는 $24.6{\pm}1.5^{\circ}C$로 측정 되었으며 평균 $10.5^{\circ}C$의 온도 감소를 보였다. 관절 종창이 없는 군과 관절 종창이 경도(+1)인 군 관절 종창이 없는 군과 중등도(+2)인 군간에서의 술 전 슬관절의 온도는 통계적으로 유의한 차이를 보였다(p<0.01), 단지 관주용액의 온도와 수술 시간을 술 후 슬관절 온도와 비교할 때, 관주용액의 온도가 낮을수록(p<0.01), 수술 시간이 길수록 술 후 슬관절 온도가 낮았다.(p<0.01). 결론 : 관주용액의 온도를 체온과 유사하게하고 관주용액을 사용하는 수술 시간을 가능한 줄이도록 노력하는 것이 좋을 것으로 사료된다.