• 한국지반환경공학회 논문집
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• 제9권7호
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• pp.73-85
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• 2008

우리나라에는 1995년부터 전국에 지하수 관측소를 설치하여 2005년에 320개소를 완료하였으며, 일 4회 지하수위 자료가 자동 측정되고 있다. 지하수 수위 강하곡선법으로 산정한 관측 지점에서의 지하수 함양율 자료의 평균값을 유역 평균 함양율로 사용하는 것은 대표성이 결여되어 있기 때문에 한계가 있다. 따라서, 본 연구에서는 지하수위 미계측 지역을 대상으로 지하수 함양율을 추정할 수 있도록 223개 관측 지점의 특성 인자와 지하수 함양율과의 관계를 통계적 기법을 활용하여 분석하고 이를 토대로 회귀모형을 구축하였다. 본 연구에서는 군집분석을 통하여 분석대상 관측정을 선정하고, 분산분석을 통하여 지하수 함양량 추정에 필요한 4가지 인자(대상 지점 인근하천의 규모, 하천까지 거리, 지형 경사도, 암석 성인)를 추출하였으며, 이들 인자에 대한 각 관측지점의 특성 자료를 수집하여 회귀 모형에 적합시킨 결과 미계측 지역의 지하수 함양율 추정이 가능한 것으로 평가되었다.

• 한국식품위생안전성학회지
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• 제11권4호
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• pp.315-321
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• 1996

Various antimicrobial drug screen tests have been used in order to ensure food safety. However, the conventional screen tests, the Swab Test on Premises(STOP, USA), the Calf Antibiotic and Sulfa Test(CAST, USA) and the European Economic Community 4-plate Test(FPT, EU) are not sufficiently rapid or sensitive enough to detect low levels of sulfa drugs in meat. We developed a new screen test kit for the determination of the antimicrobial residues in meat called the Bacillus megaterium Disk Assay(BmDA). A comparison of BmDA with the older screen tests showed BmDA was as good as the older ones with several advantages. The new test kit is faster-it can be read in 4∼6 hours instead of 16∼18 hours. Moreover, BmDA can discriminate sulfa drugs from other antimicrobial drugs because p-aminobenzoic acid countacts the inhibiting action of sulfa drugs. Minimum detectable levels of sulfa drugs were significantly improved at the lever of 0.025*0.1 pp, compared with the level of 1.0 ppm in FPT. A comparison of BmDA with the older screen tests in HPLC confirmed meat samples exceeded the Korean tolerance value of 0.1 ppm showed BmDA was the most sensitive in the microbiological screen tests. As the microbiological screen tests have already known, a person familiar with simple laboratory techniques should have no difficulty in using it to detect antimicrobial residues in meat. This would be a simple, economic method of antimicrobial residues detection which might be succesfully used by many laboratories.

• Asian Pacific Journal of Cancer Prevention
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• 제14권9호
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• pp.5397-5402
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• 2013

The rates of morbidity and mortality of hepatocellular carcinoma (HCC) have not lessened because of difficulty in treating tumor metastasis. Mongolian Saussurea involucrata (SIE) possesses various anticancer activities, including apoptosis and cell cycle arrest. However, detailed effects and molecular mechanisms of SIE on metastasis are unclear. Thus, the present study was undertaken to investigate antimetastatic effects on HCC cells as well as possible mechanisms. Effects of SIE on the growth, adhesion, migration, aggregation and invasion of the SK-Hep1 human HCC cell line were investigated. SIE inhibited cell growth of metastatic cells in dose- and time-dependent manners. Incubation of SK-Hep1 cells with $200-400{\mu}g/mL$ of SIE significantly inhibited cell adhesion to gelatin-coated substrate. In the migration (wound healing) and aggregation assays, SIE treated cells showed lower levels than untreated cells. Invasion assays revealed that SIE treatment inhibited cell invasion capacity of HCC cells substantially. Quantitative real time PCR showed inhibitory effects of SIE on MMP-2/-9 and MT1-MMP mRNA levels, and stimulatory effects on TIMP-1, an inhibitor of MMPs. The present study not only demonstrated that invasion and motility of cancer cells were inhibited by SIE, but also indicated that such effects were likely associated with the decrease in MMP-2/-9 expression of SK-Hep1 cells. From these results, it was suggested that SIE could be used as potential anti-tumor agent.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 춘계학술대회 논문집
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• pp.808-813
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• 2011

There are hundreds of thousands call center workers wearing acoustic device. However, researches and noise exposure measurements on the noise transmitted from acoustic devices have seldom been performed due to the difficulty of measurement and to the absence of the measuring method in Korea. The aim of this study is to set up management measures to protect hearing loss on the call operator by acquiring measurement data of noise transmitted from the headset Noise exposure measurements of 17 operators were performed in 7 call centers and Head and Torso Simulator method in compliance with the ISO Standard 11904-2 was used for the measurement of noise transmitted from the headset Sound pressure levels(SPL) transmitted from the headset were 73.2~86 dB(A). The operator exposed to the highest SPL set up his volume control at 9 which was the highest volume level. The volume control level, adjustable from 1 to 9, could be identified 12 out of 17 operators and the range of volume levels was 4.5~9. As a result of Pearson Correlation Analysis, the correlation between volume level and SPL transmitted from the headset showed high relation as significance at the 0.672 level(p<0.05). To protect hearing loss of call center operators, it is more practical and effective measure to limit the volume level below the noise exposure level, i.e. 85 dB(A), rather than to carry out noise monitoring considering cost-effective aspect.

• 대한인간공학회지
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• 제26권2호
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• pp.45-59
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• 2007

The operating tasks of overhead crane have caused undue stress to the operators from physical, mental, and environmental workload. Existing workload assessment models for musculoskeletal disorders such as OWAS, RULA, and QEC have limited applicability to the crane operating tasks because they focus mainly on physical factors and do not consider the relative importance of each factor. The present study was to develop a workload assessment model customized to overhead crane operation, following a systematic process: (1) analyzing task characteristics, (2) selecting workload factors, (3) developing assessment methods, (4) establishing action levels, and (5) computerizing the assessment model. Based on literature review, worksite survey, and focus group interview, 4 physical factors (awkward posture, static posture, repetitive motion, and excessive force), 6 mental factors (visual demand, auditory demand, task complexity and difficulty, time urgency, work schedule related stress, and safety related stress), and 4 environmental factors (noise, vibration, dust, and temperature) were selected and their rating scales and relative weights were determined. Then, based on the workload assessment results of 8 overhead cranes operated at different workplaces, the action levels of each factor category were established. Finally, the crane operation assessment model was computerized for effective analysis and report preparation. The present approach is applicable to develop a customized workload assessment model for an operating task under consideration.

• 한국소음진동공학회논문집
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• 제21권7호
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• pp.615-621
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• 2011

There are hundreds of thousands call center workers wearing acoustic device. However, researches and noise exposure measurements on the noise transmitted from acoustic devices have seldom been performed due to the difficulty of measurement and to the absence of the measuring method in Korea. The aim of this study is to set up management measures to protect hearing loss on the call operator by acquiring measurement data of noise transmitted from the headset. Noise exposure measurements of 17 operators were performed in 7 call centers and head and Torso simulator method in compliance with the ISO standard 11904-2 was used for the measurement of noise transmitted from the headset. Sound pressure levels(SPL) transmitted from the headset were 73.2~86 dB(A). The operator exposed to the highest SPL set up his volume control at 9 which was the highest volume level. The volume control level, adjustable from 1 to 9, could be identified 12 out of 17 operators and the range of volume levels was 4.5~9. As a result of pearson correlation analysis, the correlation between volume level and SPL transmitted from the headset showed high relation as significance at the 0.672 level(p<0.05). To protect hearing loss of call center operators, it is more practical and effective measure to limit the volume level below the noise exposure level, i.e. 85 dB(A), rather than to carry out noise monitoring considering cost-effective aspect.

• 예술인문사회 융합 멀티미디어 논문지
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• 제9권3호
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• pp.241-250
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• 2019

이 연구는 TOPIK 급수 3급 이상의 외국인 유학생을 대상으로 전자설문을 활용한 '한국 속담' 인지정도를 파악하는데 목적이 있다. 응답자 53명 중 해당 급수에 해당하는 응답자는 45명이 되었으며, 기본정보 외에 추가질문을 통해 자료를 얻었다. 연구결과, 한국어 학습 방법으로는 모국과 한국의 교육기관에서의 수업이 80.0%로 나타났으나 교육기관을 통한 속담 학습은 57.8%에 불과한 것으로 나타났다. 외국인 유학생들의 한국 속담에 대한 높은 관심의 증가에도 불구하고 그 기대에 부응하는 체계적 속담 교육이 이루어지지 않았다. 그리고 이들은 한국 속담의 비유적 표현을 어렵게 인식하였다. 또한 이들의 TOPIK 급수 소지에 비해 한국 속담을 이해하는 수준은 매우 낮은 것으로 나타났다. 체계적 속담 교육의 부재는 한국 속담의 비유적 표현을 이해하기 힘들게 하는 원인으로 파악된다. 학업 후 한국어 교수자가 되고자 하는 외국인 유학생의 수가 많은 만큼 속담 학습이 개인학습으로 그치기 보다 한국어 교육과 같이 한국 속담 교육의 체계적 학습이 이루어지도록 개선되어야 할 필요가 있다.

• 대한지역사회영양학회지
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• 제24권2호
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• pp.117-126
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• 2019

Objectives: This study was conducted to investigate the current difficulties surrounding children's obesity management and evaluate the application of a mobile phone as a tool to overcome such difficulties of obesity management from the perspective of main caregivers of elementary school students. Methods: The qualitative data were collected through 3 focus group interviews including 6 full-time housewives, 7 mothers with overweight children, and 4 working mothers. Data were analyzed using a thematic approach. Results: The limitations of current children's obesity management included difficulty in diet management and exercise as well as challenges of setting goals and lack of support at the household and school levels. Mobile technology may be useful to overcome the current problems by providing real-time knowledge on diet management and physical activity, online compensation scheme according to goal setting, and interactive environmental supports at both household and school levels for promoting overall health. Conclusions: The mobile-based multiple support program may assist in overcoming the current limitations of child obesity management by providing tailored information and by creating a more supportive environment.

• 대한통합의학회지
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• 제9권3호
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• pp.125-134
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• 2021

Purpose : This study applies inspiratory muscle resistance exercise with aerobic exercise to smokers and nonsmokers and then determines whether subjects' breathing functions (FVC, FEV1) are increased and how much effect smoking has on the difference in the increase of breathing functions between the two groups. Methods : For this experiment, 26 male adults were selected and randomly allocated to the smoker group (n=13) and nonsmoker group (n=13). The smokers and nonsmokers performed the inspiratory muscle resistance exercise with aerobic exercise three times a week for four weeks. Regarding the breathing functions, the forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) were measured three times: week 0, week 2, and week 4. The aerobic exercise was performed using a stationary bicycle with 8 difficulty levels. The inspiratory muscle resistance exercise was performed using Power Breathe with 10 resistance levels. Results : The study found that the FVC and FEV1 values of the smoker group decreased slightly after four weeks of inspiratory muscle resistance exercise with aerobic exercise. In other words, the difference was not statistically significant. In contrast, the FVC and FEV1 values of the nonsmoker group increased by a statistically significant amount. In addition, the intergroup comparison of the average increases in FVC and FEV1 values showed statistically significant differences. Conclusion : The results of this study show that when inspiratory muscle resistance exercise with aerobic exercise was performed, the increase in the breathing functions of nonsmokers was higher than that of smokers. This confirms that, within the parameters of the study, smoking had a negative effect on the increase of breathing functions. This suggests that quitting smoking must be considered as an essential factor when applying a breathing physiotherapy or a breathing function improvement program in clinical settings

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2021년도 제64차 하계학술대회논문집 29권2호
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• pp.305-307
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• 2021

Alzheimer's Disease (AD) is a cognitive disorder characterized by memory impairment that can be assessed at early stages based on administering clinical tests. However, the AD pathophysiological mechanism is still poorly understood due to the difficulty of distinguishing different levels of AD severity, even using a variety of brain modalities. Therefore, in this study, we present a hybrid EEG-fNIRS modalities to compensate for each other's weaknesses with the help of Machine Learning (ML) techniques for classifying four subject groups, including healthy controls (HC) and three distinguishable groups of AD levels. A concurrent EEF-fNIRS setup was used to record the data from 41 subjects during Oddball and 1-back tasks. We employed both a traditional neural network (NN) and a CNN-LSTM hybrid model for fNIRS and EEG, respectively. The final prediction was then obtained by using majority voting of those models. Classification results indicated that the hybrid EEG-fNIRS feature set achieved a higher accuracy (71.4%) by combining their complementary properties, compared to using EEG (67.9%) or fNIRS alone (68.9%). These findings demonstrate the potential of an EEG-fNIRS hybridization technique coupled with ML-based approaches for further AD studies.