전기비저항 및 시추 ‧ 검층자료의 상관해석을 통한 소규모 산사태 지역의 지질 연약대 파악

이선중 ( Sun-joong Lee ),강유경 ( Yu-gyeong Kang ),이철희 ( Cheol-hee Lee ),전수인 ( Su-in Jeon ),김지수 ( Ji-soo Kim ) 대한지질공학회 2020 지질공학 Vol.30 No.1

2014년 충남 태안 신진도리의 해안지역에서 일어난 작은 산사태 지역의 지하구조를 파악하기 위하여 전기비저항 및 하향식 탄성파탐사와 시추 · 물리검층을 실시하였다. 시추 · 검층자료에서 산사태 발생지역의 상부에 위치한 시추공 BH-2의 5~7 m 깊이에서 N값이 현저히 낮아지는 것을 확인하여 하향식 탄성파탐사를 추가 실시하고 이 깊이에서 지질 연약대가 연장되는 것으로 가정하여 하부의 시추공 BH-1 지점까지 전기비저항 탐사를 실시하였다. 8 m 내외의 두께를 갖는 150 Ω · m 이하의 저비저항 이상대는 시추 · 검층자료에서 해석된 세립 실트질 점토로 이루어진 풍화토층과 잘 상관되었다. 시추공 BH-2에 걸쳐있는 지질 연약대는 시추공 BH-1에 비해 상대적으로 작은 밀도 1.6~1.8 g/cm³와 150 Ω · m 이하의 비교적 낮은 전기비저항로 나타나며 포아송 비는 깊이에 따라 그 편차가 크게 나타난다. 이 지역의 산사태는 초과 강수와 이로 인한 상승 지하수면의 영향으로 물을 함유한 실트질 점토를 많이 포함하고 있는 풍화토가 전단력이 감소되어 미끄럼 활동으로 나타난 것으로 해석하였다. Electrical resistivity and downhole seismic surveys were conducted together with bore investigations and well-logging to examine subsurface structures in small-scale landslides at Sinjindo-ri, Geunheung-myeon, Taean-gun, Chungcheongnam-do, Republic of Korea in 2014. On the basis of the low N-values at depths of 5~7 m in borehole BH-2, downhole seismic and electrical dipole-dipole resistivity surveys were performed to delineate geological weak zones. The low-resistivity zones (<150 Ω · m) measure ~8 m in thickness and show a close depth correspondence to weathered soils consisting mainly of silty clays as identified from the bore investigations and well-logging data. Compared with weak zones in borehole BH-1, weak zones in BH-2 are characterized by lower densities (1.6~1.8 g/cm³) and resistivities (<150 Ω · m) and greater variation in Poisson’s ratio. These observations can be explained by the presence of wet silty clays rich in weathered soil material that have resulted from heavy rainfall and rises in groundwater level. Downslope movements are probably caused by the sliding of wet clay that acts to reduce the strength of the weathered soil.

산업폐수의 총유기탄소(TOC) 특성 - 전남 동부권 사업장을 중심으로 -

박보영 ( Bo-young Park ),문희 ( Hee Moon ),허동화 ( Dong-hwa Heo ),전수인 ( Su-in Jeon ),신혜정 ( Hea-jung Sin ),박송인 ( Song-in Park ),김양기 ( Yang-gi Kim ) 한국환경기술학회 2022 한국환경기술학회지 Vol.23 No.6

TOC was applied to the effluent new standard as a substitute of COD_Mn. But the setting of the TOC did not reflect the characteristics of various wastewater, such as the treatment facility size and the discharge type. This study assessed each industrial facility in terms of water quality characteristics by replacing COD_Mn with TOC. In the study, 96 data groups across ten industrial categories based on the Korean Standard Industrial Classification were measured COD_Mn and TOC to obtain data about waste water discharge facilities in the eastern parts of Jeollanam-do province. The measurements show that the mean COD_Mn and TOC concentration were in the ranges of 4.2 mg/L ∼ 82.0 mg/L and 3.7 mg/L ∼ 195.4 mg/L, respectively. The relative ratio(COD_Mn/TOC) was 0.42 ∼ 1.50 and the oxidation rate of COD_Mn was 12.69 % ∼ 45.45 %. The TOC emission rate against the acceptable emission criteria was in the range of 7.73 % ∼ 100.72 %. The result of TOC and COD_Mn was 82.0 mg/L and 195.4 mg/L in other food manufacturing facilities, 8.5 mg/L and 14.2 mg/L in basic petrochemical compound manufacturing facilities, 24.8 mg/L and 25.7 mg/L in transportation equipment repair and car washing or cleaning facilities. Correlations among different organic matters were analyzed according to business categories, and the results show a range of 0.9813 ∼ 0.3742, which points to huge differences among business categories. In addition, the study examined 10 items in 4 Establishments, whose wastewater discharge was less than 200 m3. The result showed that their organic matter discharges had been underestimated as they were in the food industry. These results raise a concern with the possibilities of their exceeding the criteria in case of TOC application and a need for them to improve their processes and consequently change their management methods.

외과계 중환자에서의 초기 정맥영양공급의 현황 분석과 열량대단백비의 임상적 의의

허은정 ( Eun Jeong Heo ),박가영 ( Ka Young Park ),전수정 ( Su Jeong Jeon ),남궁형욱 ( Hyungwook Namgung ),이은숙 ( Eun Sook Lee ),송인애 ( In Ae Song ) 한국정맥경장영양학회 2015 한국정맥경장영양학회지 Vol.7 No.3

Purpose: Surgical critically ill patients require adequate nutrition support and the American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.) guidelines recommend low non-protein calorie: nitrogen ratio (NPC:N ratio, 70∼100) for critically ill pateints. In this study, we assess the current use of early parenteral nutrition of surgical critically ill patients and analyze the clinical significance of NPC:N. Methods: This is a retrospective study of critically ill adult patients who remained in the intensive care unit (ICU) for over 3 days and could not receive enteral nutrition for the first 7 days. Data on parenteral intake of patients were collected from electronic medical records. Association of NPC:N scores with clinical outcome (length of ICU stay, length; of hospital stay, duration of ventilation, and mortality) were analyzed using Pearson correlation and multiple regression. Results: The study included 72 cases, average parenteral calorie intake was 14.6 kcal/kg/day and protein intake was 0.5 g/kg/day. We assessed the NPC:N scores to determine the patients’ NPC:N for the first 7 days in ICU close to the A.S.P.E.N guidelines. NPC:N scores showed weak negative correlation with length of hospital stay and duration of mechanical ventilation (r=-0.259, P=0.028; r=-0.495, P=0.001). Multiple regression adjusted with APACHE (Acute Physiology and Chronic Health Evaluation) II score, age, and body mass index showed correlation of higher NPC:N score with decreased length of hospital stay and shorter duration of ventilation (P=0.0001, P=0.035, respectively). However, length of ICU stay and mortality within 60 days showed no significant correlation with NPC:N scores. Conclusion: Parenteral calories and protein intakes of critically ill patients in ICU were lower in comparison to A.S.P.E.N. recommendation in this study. Low NPC:N scores might be related to shorter length of hospital stay, duration of mechanical ventilation. Consultation of a nutritional support team could have a positive effect in providing appropriate nutrition support.

육성 탄성파 반사법 탐사자료에서 방사형 트레이스 변환를 이용한 선형 잡음 제거

전수인 ( Su In Jeon ),주현태 ( Hyeon Tae Ju ),이성중 ( Sun Joong Lee ),김지수 ( Ji Soo Kim ) 대한지질공학회 2011 대한지질공학회 학술발표회논문집 Vol.2011 No.1

고체추진제 연소속도 측정의 정밀도 향상을 위한 초음파 신호 잡음제거 기술 연구

전수균(Su-Kyun Jeon),송성진(Sung-Jin Song),김학준(Hak-Joon Kim),고선필(Sun-Feel Ko),오현택(Hyun-Taek Oh),김인철(In-Chul Kim),유지창(Ji-Chang Yoo),정정용(Jung Yong Jung) 한국추진공학회 2009 한국추진공학회 학술대회논문집 Vol.2009 No.5

기존 연구를 통해 초음파법을 이용한 고체추진제 연소속도 측정 시스템 및 연소속도 산정 기법을 개발하였으며, 스트랜드버너법과 비교하여 두 측정 기법의 특성을 비교해보았다. 그 결과 초음파법은 측정된 추진제의 잔존길이를 연소시간으로 미분함으로써 고체 추진제의 연소속도를 계산하기 때문에 한번의 시험으로 넓은 압력구간에 걸쳐 고체추진제 연소속도를 구하는 장점이 있으나, 초음파 측정신호의 잡음이 연소속도의 정밀도 및 신뢰성에 영향을 미침을 알 수 있었다. 따라서, 본 연구에서는 압력시험과 연소시험에서 획득한 측정신호의 잡음 제거 기법을 제안하고, 제안된 기술을 적용하여 연소속도를 측정한 결과와 제안된 기술을 적용하지 않은 경우를 비교하여 제안된 기술의 성능을 평가하였다. Ultrasonic techniques have the advantage of determining the burning rates with wide range of pressure in only a single test. However, ultrasonic techniques have a drawback, which is that they are using high frequency transducers and it is easily affected by noise. Therefore, ultrasonic measurement method needs noise reduction algorithm to improve or grantee accuracy of burning rate measurements of solid propellants using ultrasound. Thus, in the present study, we propose a noise reduction method of measured ultrasonic signals by applying wavelet shrinkage.

하수처리수 재이용을 위한 수질 현황과 활용방안 연구

전수인 ( Su-in Jeon ),문희 ( Hee Moon ),박보영 ( Bo-young Park ),허동화 ( Dong-hwa Heo ),박찬오 ( Chan-oh Park ) 한국환경기술학회 2021 한국환경기술학회지 Vol.22 No.2

This study aimed to improve the reuse rate of reclaimed water by analyzing the water quality of inflow and discharge water and suggesting an reprocessing strategy for the reclaimed water from five sewage treatment plants in eastern Jeollanam-do. A total of 30 water quality parameters, including 16 general water quality and 14 heavy metal parameters, were analyzed following the water quality standards for reclaimed and discharged water. The results of the analysis confirmed that the reclaimed water from the Yeosu plant could be used for washing, waterhead and river maintenance water; the reclaimed water from Suncheon, Gwangyang Jungang and Gokseong for washing, waterhead, landscaping, and river maintenance; and the reclaimed water from Gwangyang for washing and waterhead. For the reclaimed water to be used for cleaning, toilet flushing, recreational use, or agricultural, an appropriate treatment method, such as chlorine disinfection, activated carbon adsorption, or reverse osmosis, needs to be selected to reprocess the reclaimed water after checking the water quality parameters. If the discharged water meets the water quality standards for reclaimed water, it can be reused or supplied immediately. Therefore, sewage treatment facilities should have a daily assessment of pH, turbidity, bound residual chlorine, odor, and color, weekly measurement of BOD, TN, TP, and total coliforms, and quarterly evaluation of chloride, electrical conductivity, and other heavy metals. These strategies will likely contribute significantly to increasing the reuse rate of reclaimed water.

다검출기 불활성기체 질량분석기를 활용한 <SUP>40</SUP>Ar-<SUP>39</SUP>Ar 연대 측정

김정민(Jeongmin Kim),전수인(Su-In Jeon) 대한지질학회 2013 대한지질학회 학술대회 Vol.2013 No.10

논문 : 엔지니어링 탄성파자료에서 방사변환을 통한 풍화대 및 기반암 표면의 영상강화

김지수 ( Ji Soo Kim ),전수인 ( Su In Jeon ),이선중 ( Sun Joong Lee ) 대한지질공학회 2012 지질공학 Vol.22 No.4

엔지니어링 탄성파 반사법 자료에서 자주 부딪히는 문제는 천부 불연속면의 작은 반사 에너지가 발파로 인한 음파, 직접파, 굴절파 및 진폭이 큰 표면파와 같은 잡음으로 가려진다는 점이다. 자료처리 과정에서 그 동안 국내 지반탐사 자료에 적용되지 않았던 방사변환 기법을 통하여 현장에서 얻어진 거리-시간 영역의 자료를 단순히 속도-시간 영역의 자료로 변환시켜 일관성 잡음을 제거하고자 하였다. 적용성 평가를 위해 수백 미터 깊이를 대상으로 하는 고품질의 퇴적분지 탐사자료와 수십 미터 깊이를 대상으로 하는 잡음이 많은 엔지니어링 탐사자료를 시험자료로 선택하였다. 이 방법은 대역 통과 필터링과 주파수-파수 필터링에 비해 반사파의 진폭을 약화시키지 않고 음파, 표면파, 직접파, 굴절파와 같은 천부된 저주파 제거 필터를 적용할 때 표면파 분산 구간은 물론 주파수-파수 필터링에서 통제하기 힘든 직접파, 굴절파 및 음파의 중첩 구간(50m 깊이 이내)에 있는 천부 반사면들이 효과적으로 부각되었다. 일관성 있는 선형 잡음에 제한되어 적용되는 이 방법은 앞으로 속도-시간 영역에서 각 종 잡음의 분포 특성을 정확히 파악할 때 엔지니어링 자료에 흔히 나타날 수 있는 절리, 파쇄대, 천부 단층에 의한 회절파와 역-산란파와 같은 잡음도 충분히 조절할 수 있을 것으로 보인다. A difficulty encountered in engineering seismic mapping is that reflection events from shallow discontinuities are commonly overlapped with coherent noise such as air wave, direct waves, head waves, and high-amplitude surface waves, Here, the radial trace transform, a simple geometric re-mapping of a trace gather(x-t domain) to another trace gather(v-t domain), is applied to investigate the rejection effect of coherent linear noises. Two different types of data sets were selected as a representative database: good-quality data for intermediate sounding (hundreds of meters) in a sedimentary basin and very noisy data for shallow(≤50m) mapping of the weathered zone and bed-rock surface. Results obtained with cascaded application of the radial transform and low-cut filtering proved to be as good as, or better than, those produced using f-k filtering, and were especially effective for air wave and direct wave. This simple transform enables better understanding of the characteristics of various types of noise in the RT domain, and can be generally applied to overcoming diffractions and back-scatterings caused by joints, fractures, and faults commonly that are encountered in geotechnical problems.

전곡 지역 제4기 현무암질 암석의 <SUP>40</SUP>Ar-<SUP>39</SUP>Ar 연대

김정민(Jeongmin Kim),최정헌(Jeong-Heon Choi),전수인(Su-In Jeon),박울재(Wooljae Park),남성수(Seongsu Nam) 대한지질학회 2014 대한지질학회 학술대회 Vol.2014 No.10

전곡 지역 제4기 현무암질 암석의 <SUP>40</SUP>Ar-<SUP>39</SUP>Ar 연대 측정

김정민(Jeongmin Kim),최정헌(Jeong-Heon Choi),전수인(Su In Jeon),박울재(Ul Jae Park),남성수(Seong Soo Nam) 한국암석학회 2014 암석학회지 Vol.23 No.4

한반도 중부 전곡 지역 한탄강 유역에는 제4기 시기에 분출한 현무암질 암석들이 화산대지 및 하식절벽으로서 분포한다. 국내 최초로 도입된 다검출기 불활성기체 질량분석기와 레이저 가열장치를 이용하여 전곡 지역에서 산출하는 현무암질 암석의 <SUP>40</SUP>Ar-<SUP>39</SUP>Ar 연대를 측정하였다. 전곡읍 은대리 지역 하식절벽의 현무암들은 하부에서 상부로 가면서 0.54±0.07 Ma, 0.48±0.01 Ma, 0.12±0.01 Ma의 연대를 나타내며 전곡리 지역의 현무암에서 0.43±0.04 Ma의 연대가 얻어진다. 이 결과는 0.12-0.54 Ma 사이에 전곡 지역에 단속적인 화산암의 분출이 있었을 가능성을 시사한다. Quaternary basaltic rocks occur as volcanic plateau and/or river cliff in the watershed area of Hantan River in Jeongok, central Korea. We measured <SUP>40</SUP>Ar-<SUP>39</SUP>Ar ages for the basaltic rocks from Jeongok area using the multi-collector noble gas mass spectrometer and laser heating device introduced for the first time in Korea. The basaltic rocks from the river cliff in Eundae-ri area show the systematic change in <SUP>40</SUP>Ar-<SUP>39</SUP>Ar ages from 0.54±0.07 Ma through 0.48±0.01 Ma to 0.12±0.01 Ma toward the top. The other sample from Jeongok-ri area yields the age of 0.43±0.04 Ma. This results suggest that there might be a episodic volcanic eruption between 0.12-0.54 Ma in Jeongok area.