클래스 불균형 문제가 있는 텍스트 데이터를 분류하기 위한 상호정보량 기반 특징 선택 기법

서민지,안길승,허선 한국시뮬레이션학회 2017 한국시뮬레이션학회 학술대회집 Vol.2017 No.-

전기화학 기반의 전기 변색 센서 연구 동향

서민지,Seo, Minjee 한국전기화학회 2022 한국전기화학회지 Vol.25 No.4

Along with the increasing need for point-of-care diagnostics, development of portable, user-friendly, as well as sensitive sensors have gained intensive attention. Among various strategies, electrochromic sensors, which are electrochemically operated colorimetric sensors, have been actively studied. With their ability to report the presence and concentration of analytes by optical signals, electrochromic sensors utilize the advantages of both electrochemical and colorimetric sensors, enabling the simplification of device composition as well as convenient interpretation of results. Up to date, electrochromic sensors have been applied for a wide range of analytes, and further developments such as the introduction of flexible platforms or self-powered systems have been reported, providing a path towards the development of wearable sensor devices. In this review, various types of electrochromic sensors, according to the main strategy in which the electrochemical signals are converted to colorimetric signals, are introduced.

실험적 간장해에 의한 지질 함량 변동에 대한 택사 추출액의 영향

서민지,하헌,윤수홍,Seo, Min-Ji,Ha, Hun,Yoon, Soo-Hong 환경독성보건학회 1995 환경독성보건학회지 Vol.10 No.3

The protective and therapeutic effects of Alismatis Rhizoma extracts on rat liver injury induced by carcinogenic polycyclic hydrocarbon, benzo(a)pyrene were investigated in rats. Serum and liver triglyceride, total-cholesterol level and serum HDL-cholesterol content were measured. Alismatis Rhizoma extracts inhibited the enhanced production of lipid in chemically induced liver injury. Among 4 fractions, CHCh fraction revealed the most powerful liver-protective effect. Our results strongly suggest that Alismatis Rhizoma be a promising liver-protective agent.

B도시지역 고층 주상복합건축물 성능위주설계도서 분석을 통한 화재 시뮬레이션 분야 개선방안에 관한 연구

서민지,이양주,안성호,황철홍,최준호 한국화재소방학회 2017 한국화재소방학회논문지 Vol.31 No.4

Recently, in Korea, construction of high-rise buildings has been rapidly increasing. Therefore, in order to minimize the lossof life and property in the event of a fire, “performance-based design” which requires performance equal to or better thancurrent regulations is obligatorily required. However, in the field of fire and evacuation simulation, which occupies a largepart in the performance-based design, detailed technical guidelines have not yet been established. Therefore, various designersare proceeding with the computer simulation modelling by referring to the design report book previously performed. Especially,in the case of the fire simulation, according to the judgment of a designer the scenario type is selected and the input valuesis set. Even if the building is used for the same purpose, it is true that the result can be different depending on how andwho designed it. Therefore, in this paper, we have investigated the fire scenarios type and scenarios input values by randomlyexamining 7 preliminary reports of performance-based design in B metropolitan city. We also propose the improvementstrategy for fire simulation and lay the groundwork for establishment of technical guidelines for fire simulation forperformance-based design. 최근 우리나라에서는 초고층 건축물의 신축이 급증하고 있어 화재 발생 시 인명 및 재산피해를 최소화하기 위해현행 법규와 동등 이상의 성능을 요구하는 ‘성능위주설계’를 의무적으로 시행하고 있다. 그러나 성능위주설계에서큰 비중을 차지하고 있는 화재 및 피난 시뮬레이션 분야는 아직 세부적인 기술적 가이드라인이 제정되지 않아 설계자들이 앞서 수행했던 여러 설계도서들을 참고하여 그와 유사하게 진행하고 있는 실정이다. 그 중에서도 화재시뮬레이션의 경우에는 설계자의 판단에 따라 시나리오 유형을 선정하고 임의로 입력값을 설정하고 있어 같은 용도의 건축물이라 하더라도 누가 어떻게 설계했느냐에 따라 다른 결과가 도출되고 있는 것도 사실이다. 이에 본 논문에서는실제 B도시지역에 접수된 성능위주설계(건축심의 전 단계) 도서 7건을 무작위로 조사하여 화재시나리오 유형과 시나리오별 입력조건 현황을 파악하고 합리적인 화재시뮬레이션의 수행을 위한 개선방안을 제시하여 기술적 가이드라인 제정에 대한 초석을 다지고자 한다.

실험적 간장해에 의한 지질 함량 변동에 대한 택사 추출액의 영향 ( Effects of Alismatis Rhizoma Extracts on Lipid Components in Experimental Liver Injury )

서민지,하헌,윤수홍 환경독성보건학회 1995 환경독성보건학회지 Vol.10 No.2

Enhanced electrocatalytic activity by nanoconfinement effects at nanoporous indium tin oxide electrodes

서민지,배제현 대한화학회 2024 Bulletin of the Korean Chemical Society Vol.45 No.12

Among various strategies to enhance electrocatalytic activity, nanoporous structured electrodes have been widely utilized owing to their improved performance. Along with enlarged electrode surface, modified crystalline facets, and surface defects of nanoporous electrodes, recent studies have reported their unique electrocatalytic characteristics originating from the nanoconfined space, denoted as the nanoconfinement effect. Introducing nanoporous electrodes with controllable thickness made of indium tin oxide, an electrochemically inert material, has provided an optimal platform for analyzing the contribution of nanoporous structures to the catalytic effects. Nevertheless, the scope of reactants that has been studied based on this system so far is mostly limited to ferric/ferrous redox species in sulfate anion environment. Here, using the nanoporous indium tin oxide electrodes, we demonstrate the nanoconfinement effect toward the ferric/ferrous reaction in a different chemical environment that alters its electrokinetic characteristics compared to the previous studies. Furthermore, a complex multi‐electron transfer reaction of oxygen reduction is employed to explore the effects of nanoporous structure toward inner‐sphere reactions. Our work suggests that the nanoconfinement effects can be applied to a wider range of electrochemical reactions taking place in nanoporous electrodes. Among various strategies to enhance electrocatalytic activity, nanoporous structured electrodes have been widely utilized owing to their improved performance. Along with enlarged electrode surface, modified crystalline facets, and surface defects of nanoporous electrodes, recent studies have reported their unique electrocatalytic characteristics originating from the nanoconfined space, denoted as the nanoconfinement effect. Introducing nanoporous electrodes with controllable thickness made of indium tin oxide, an electrochemically inert material, has provided an optimal platform for analyzing the contribution of nanoporous structures to the catalytic effects. Nevertheless, the scope of reactants that has been studied based on this system so far is mostly limited to ferric/ferrous redox species in sulfate anion environment. Here, using the nanoporous indium tin oxide electrodes, we demonstrate the nanoconfinement effect toward the ferric/ferrous reaction in a different chemical environment that alters its electrokinetic characteristics compared to the previous studies. Furthermore, a complex multi-electron transfer reaction of oxygen reduction is employed to explore the effects of nanoporous structure toward inner-sphere reactions. Our work suggests that the nanoconfinement effects can be applied to a wider range of electrochemical reactions taking place in nanoporous electrodes.

합성개구레이더 인공위성 영상을 활용한 중소규모 하천에서의 유량 추정

서민지,김동균,AHMAD WAQAS,차준호 한국수자원학회 2018 한국수자원학회논문집 Vol.51 No.12

This study suggests a novel approach of estimating stream flow discharge using the Synthetic Aperture Radar (SAR) images taken from 2015 to 2017 by European Space Agency Sentinel-1 satellite. Fifteen small to medium sized rivers in the Han River basin were selected as study area, and the SAR satellite images and flow data from water level and flow observation system operated by the Korea Institute of Hydrological Survey were used for model construction. First, we apply the histogram matching technique to 12 SAR images that have undergone various preprocessing processes for error correction to make the brightness distribution of the images the same. Then, the flow estimation model was constructed by deriving the relationship between the area of ​​the stream water body extracted using the threshold classification method and the in-situ flow data. As a result, we could construct a power function type flow estimation model at the fourteen study areas except for one station. The minimum, the mean, and the maximum coefficient of determination (R2) of the models of at fourteen study areas were 0.30, 0.80, and 0.99, respectively. 본 연구에서는 2015년에서 2017년 사이에 유럽항공우주국 Sentinel-1 위성이 촬영한 Synthetic Aperture Radar (SAR) 영상을 활용하여 한강 유역 내 하천의 유량을 추정하는 모형을 개발하였다. 한강 유역 내 15개 중소규모 하천을 연구지역으로 선정하였으며 SAR 인공위성 영상 자료와 수위 및 유량관측소에서 산정한 유량 자료를 모형 구축을 위하여 사용하였다. 우선, 오류 보정을 위해 다양한 전처리 과정을 거친 12장의 SAR 영상을 히스토그램 매칭 기법을 적용하여 이미지의 밝기 분포를 동일하게 만들었다. 이후 임계치 분류방식을 사용하여 추출된 하천 수체의 면적과 지상관측유량자료와의 관계식을 도출하여 유량추정모형을 구축하였다. 그 결과, 1개소를 제외한 14개 관측소에서 인공위성에서 추출한 하천 면적을 입력 자료로 하는 멱함수 형태의 유량추정모형을 구축할 수 있었다. 14개 관측소의 최소, 평균, 최대 결정 계수(R2)는 0.3, 0.8, 0.99로 나타났다.

대학생의 내현적 자기애와 대학생활적응의 관계에서 자기자비에 대한 매개효과 연구

서민지 한국콘텐츠학회 2024 한국콘텐츠학회논문지 Vol.24 No.10

본 연구는 대학생의 내현적 자기애, 자기자비가 대학생활적응에 미치는 영향을 살펴보고 내현적 자기애와 대학생활적응의 관계에서 자기자비의 매개효과를 규명하고자 하였다. 본 연구는 대학생을 대상으로 설문조사를 실시하였고, 수집된 자료는 SPSS 24.0, AMOS 24.0을 사용하여 통계분석을 실시하였다. 본 연구의 결과는 다음과 같다. 첫째, 대학생의 내현적 자기애는 자기자비에 유의한 부(-)의 영향을 미치는 것으로 나타났다. 둘째, 대학생의 자기자비는 대학생활적응에 유의한 정(+)의 영향을 미치는 것으로 나타났다. 셋째, 대학생의 내현적 자기애는 대학생활적응에 유의한 부(-)의 영향을 미치는 것으로 나타났다. 넷째, 대학생의 내현적 자기애는 자기자비를 매개로 하여 대학생활적응에 영향을 미치는 것으로 나타났다. 본 연구 결과를 통해 내현적 자기애 성향이 높은 대학생들은 그들의 자기자비 수준을 파악하고 개입 방법으로 포함함으로써 대학생활적응 수준을 향상시킬 수 있음을 제시할 수 있었다. The purpose of this study is to examine the impact of covert narcissism and self-compassion of university students upon their adaptation to university life and examine the mediating effect of self-compassion in the relationship between covert narcissism and adaptation to university life. For this purpose, the researcher surveyed university students, and the data gathered were statistically analyzed using SPSS 24.0 and AMOS 24.0. The findings of this study were as follows; the covert narcissism of university students had a significant and negative impact on self-compassion. Second, the self-compassion of university students had a significant and positive impact on adaptation to university life. Third, the covert narcissism of university students had a significant and negative impact on adaptation to university life. Fourth, the covert narcissism of university students had an impact on their adaptation to university life through mediation by self-compassion. The findings of this study showed that, for university students with a higher tendency to covert narcissism, it would be possible to enhance their adaptation to university life by means of understanding their level of self-compassion and include it as a part of intervention.

자전거 탑승 중 발생한 손상 환자에서 음주의 영향

서민지,조진성,임용수,양혁준,우재혁,최우성 대한응급의학회 2020 대한응급의학회지 Vol.31 No.4

Objective: When bike riding under the influence of alcohol, incidence of injury increases, although reports of highly severe injuries is rare. Therefore, this study aimed to determine how drinking alcohol affects bicycle injuries. Methods: This study included patients who visited the emergency departments at 23 hospitals. Participants were enrolled in the emergency department-based injury in-depth surveillance program of the Korea Centers for Disease Control and Prevention, were over 15-years-old, and were injured while riding a bike either with or without alcohol intake. Patients with important data missing or insufficient data such as Excess Mortality Ratio-adjusted Injury Severity Score (EMR-ISS) were excluded from the analysis. Results: A total of 28,094 patients were analyzed. The alcohol-intake group numbered 1,946 (6.9%) while the non-alcohol- intake group numbered 26,148 (93.1%). The incidence of severe injury (EMR-ISS≥25) in the alcohol-intake group was 451 (23.2%), whereas that in the non-alcohol-intake group was 2,881 (11.0%), which was statistically different between the two groups (P<0.001). According to multivariate logistic regression, the odds ratio of severe injuries in the alcohol-intake group was 2.04 (95% confidence interval, 1.80-2.30) compared to the non-alcohol-intake group after adjusting for age, alcohol use, type of road, sex, injury time, and transportation. Conclusion: Alcohol is associated with an increase in the incidence of severe injuries. Therefore, as part of preventive measures, it will be necessary to tighten regulations on post-drinking bike riding and improve awareness through public relations.

3-D 레이저 스캐너를 이용한 해빙 표면고도 관측

서민지,박지은,박정원,박진구,김현철 (사)지오에이아이데이터학회 2023 GEO DATA Vol.5 No.1

This study aims to introduce a sea ice elevation dataset estimated by using a 3-D laser scanner during the ice camp of the 2022 Arctic summer field survey. The equipment used is FARO’s Laser scanner FOCUS 3D X 130 HDR. The observed sea ice floe is located in the Arctic Ocean (76°13' N, 174°35') and is a multi-year ice with several melt ponds and ice ridges. We scanned eight sections separately, considering the equipment’s maximum horizontal scan range and the ice surface’s topographic features. The raw data were co-registered based on the positions of reference spheres. The result indicated a significant level of accuracy with a target-based vertical mean error of 4.8 mm. The laser scanner data were merged into point clouds ranging from 160×210 m. As a result, sea ice elevation data were generated in 0 to 2.8 m based on the minimum vertical point in the observation range. Sea ice elevation data is an essential variable in estimating the various properties of sea ice, such as ice thickness and roughness. In addition, using climatic variables such as air temperature and energy budget observed simultaneously can help to understand the physical interaction between the sea ice surface and the atmosphere on a local scale.