• Korean Journal of Microbiology
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• v.40 no.1
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• pp.49-53
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• 2004

Barley, wormwood, sea tangle, and soybean were fermented by Bacillus licheniformis B 1 to make Chungkookjang with better flavor and aroma. Maximal protease activity in mixed grains was observed one day after inoculation. pH increased to 8.4 two days after inoculation. Browning material derived from interaction between sugar and amino acids increased 20-fold. Thus, it is proved that Chungkookjang can be made in the mixed grains. Antioxidant activities of mixed fermented grains dissolved in ethanol or methanol (0.2 and 1 %) increased depending on their concentrations. Antioxidant activities were determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH). One % of powder Chungkookjang dissolved in methanol showed highest antioxidant activity. Systolic blood pressure of hypertensive volunteers who took 20 g of mixed fermented powder decreased on average by 10 mmHg in 2 h. Preference of mixed fermented soybean containing barley, wormwood, sea tangle to fermented soybean was demonstrated by t-test analysis. Mixed fermented grains can be developed as a functional food to lower hypertension.

• Journal of Information Management
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• v.30 no.3
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• pp.27-43
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• 1999

The digital library operated in the environment of computer-mediated-communication offered new successful alternative plans for the field and communication methods of the information services that have been provided by the traditional library and this causes the traditional library to move to the new paradigm. In this situation, the information services of the digital library raised the necessity for the communication channels that would cope actively on the spot and for the extention of information services that would supply an unspecified number of the general public with a considerable extention of information services that neglect time and space. This study looked into the communication channels in general for interactions between the digital library and the users in the environment of computer-mediated-communication and observed patterns of communication chennels that the digital library could supply. For the development of the communication model in the digital library, the study presented the communication model for effective information services.

• Proceedings of the Korea Water Resources Association Conference
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• 2017.05a
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• pp.21-21
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• 2017

최근 서울, 부산, 울산 등에서 도시 돌발홍수가 빈번히 발생하고 있고 이에 따른 인명 손실 및 재산 피해가 빠르게 증가하고 있다. 그러나 집중 호우의 대부분은 저고도 대기에서 생성 및 발달되며, 소멸까지의 시간은 2-3 시간에 불과하여 기존의 우리나라 수문기상 관측시스템은 이러한 유형의 강우량 예측에 많은 어려움을 겪고 있는 실정이다. 이 문제를 해결하기 위해 기상, 재난 관련 정부 기관들이 저고도 수문기상 관측을 위한 도시형 X-밴드 레이더 네트워크 구축을 계획하고 있다. 본 연구의 목적은 그보다 선행하여 돌발성 수문기상 재해연구를 위해 한국건설기술연구원에서 도입한 X-band 이중 편파 레이더 시스템을 이용하여 보다 간단하고 정확한 재난 감시 및 예경보 시스템을 개발하는데 있다. 본 연구에서는 X-밴드 레이더 데이터로부터 추정된 정량적 강수량을 모니터링 하여 도시 지역의 돌발홍수를 자동으로 경고하는 방법을 제안한다. 또한 Google 어스 플랫폼을 사용하여 정확한 3D QPE-GIS 매칭 기법을 개발함으로써, 심각한 수문기상 현상이 발생하는 정확한 위치를 추적하고 직관적인 경보서비스를 가능케 한다. 본 연구에서 제안하는 경보시스템은 레이더 데이터 분석도구, 위험결정 도구 및 위험경고 표시 도구의 세 가지 기술로 구성된다. 제안된 돌발홍수 경보시스템은, 시뮬레이션을 통해 X-밴드 레이더 데이터로부터 정량적 강수량이 계산되며, GIS 상에서 레이더 반사도 및 강우강도가 3차원 이미지 형태로 표시된다. 그런 다음 Google 어스에서 3D 큐브 블록으로 대표되는 강수량이 동시에 누적표출 되도록 설계되었다. 또한 분석된 X-밴드 레이더 데이터로부터 지역별 누적 강수량을 업데이트 및 모니터링하고 기 설정된 돌발홍수 발생 한계치(trigger)에 도달하면 홍수경보 메시지를 표시한다. 향후, 제안된 경보시스템에 대한 기술적 도구를 개선하면서 대규모 수문기상 레이더 네트워크로 광범위한 강우를 모니터링하면 전국적인 돌발홍수 경보시스템으로 확대가 가능하다.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.100-100
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• 2018

본 연구에서는 집중호우에 대한 레이더기반 초단기 강우예측 시스템의 정확도를 향상시키기 위해 초기장 개선 연구를 수행하였다. 집중호우에 적합한 강우를 추정하기 위해 층운형, 대류형, 열대형의 Z-R관계식과 반사도 조건에 따라 층운형과 적운형을 구분하여 Z-R 관계식을 적용하였으며, 이를 초단기 강우예측 시스템의 초기장으로 활용하였다. 또한 2016년 10월 5일 태풍 차바(Chaba)에 의한 집중호우 사례에 대해 지상관측 강우자료와 레이더 추정 및 예측 강우자료와의 비교를 통해 정확도를 정성적 정량적으로 평가하였다. 레이더 강우추정에 대한 분석 결과, 복합형 타입의 Z-R 관계식의 상관계수와 평균제곱근오차가 비슬산레이더의 경우 각각 0.8207, 9.22 mm/hr, 면봉산 레이더의 경우 각각 0.8001, 10.53 mm/hr로 가장 좋은 성능을 보였다. 강우 예측에 대한 분석 결과, 집중호우 사례에 대해 강우강도 공간분포 및 이동 패턴은 평균적으로 잘 모의하였으며, 초단기 강우예측 결과의 평균적으로 POD는 0.97이상, FAR는 0.21 이하로 다소 정확하게 예측하는 것으로 분석되었다. 정량적 평가 결과, 비슬산 레이더의 경우 상관계수가 예측시간 60분까지 0.545이상, 면봉산 레이더의 경우 0.379 이상으로 비교적 좋은 상관성을 보였으며, Z-R관계식 유형에 따른 차이는 작은 것으로 확인되었다. 평균제곱근오차의 경우 열대형과 복합형의 Z-R관계식이 높은 정확도를 가지는 것으로 확인되었다. 본 연구 결과, 초기장 정확도의 개선을 통한 레이더 기반 초단기 강우예측 모형의 정확도 개선 가능성을 확인할 수 있었으며, 향후 지속적인 사례연구 및 검증을 통하여 강우추정 및 강우예측 알고리즘 개선의 노력이 필요하다.

• Journal of the Korean Institute of Gas
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• v.22 no.6
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• pp.1-7
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• 2018

Currently chemical plant risk have been issued by occurring frequent accidents. Accidents can be generally composed of fire, explosion, release in chemical plant. In case of fire and explosion, accident victims are occurred immediately after accident but release accident, late emergency response cause damage to worker. Especially, there are many victims by late emergency response against chemical exposure to skin. In case of chemical exposure to skin, irreversible damage like death, blindness, burn can be prevented by washing immediately. Safety shower can provide the cleaning for chemical exposure to eye, skin. Most of chemical plants are built in 1980s so equipment become superannuated. In this reason, safety shower also cannot operate normally in emergency situation. Therefor safety shower should be managed by installation and management guideline. This study perform the establishment guideline for safety shower installation and inspection to increase the reliability.

• Journal of the Korean Society of Groundwater Environment
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• v.5 no.3
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• pp.148-154
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• 1998

Gubong gold-mine, previously one of the largest gold mines in Korea, is located at the mid-west of the South Korea. In the areas nearby the mine, the shallow groundwater was the major source for domestic and farming water-supply. Soil contamination by Cd, Cu, Pb and Zn was previously known in this area. This study is objected to identify quality of the shallow groundwater, possibly affected by the mine tailings. Samples were collected from a nearby stream, shallow groundwater and seepage from the tailings. Chemical analysis for the water quality includes major cations such as Na, K, Ca, and Mg, anions as F, Cl, NO$_3$, SO$_4$, HCO$_3$, and trace elements as Al, Cr, Mn, Fe, Ni, Cu, Zn, Cd, Pb, Se, As, Hg. Water types could be drawn into four groups from the plots of Piper, Stiff diagrams and cluster analysis. SAR-Conductivity plot indicates the water does not pose either alkalinity or salinity hazards for irrigation. Major contaminant in groundwater appeared to be arsenic, released from arsenopyrites in tailings by oxidation. Dredging of buried railing materials could stimulate the release of arsenic from the sediments to the groundwater.

• Korea Trade Review
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• v.43 no.2
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• pp.47-67
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• 2018

The purpose of this study is to determine factors of FDI inflows which positively influence economic development. While MNCs ultimately decide on which country to engage in FDI, it can be affected by the general investment environment of host countries. Thus, it may be closely linked to national macro socio-economic factors. In the fixed-effect panel regression analysis using 30 years of data of 13 developed countries and 15 developing countries, results indicate that labor redemption exerts the greatest influence on global FDI inflows; this implies that FDI decisions are based on locations featuring higher productivity by the reduction of labor costs. According to the level of economic development, the motive of FDI inflows differs. In developed countries, GDP, government expenditure and consumer expenditure exert the greatest influence on FDI inflows; which shows characteristics of market seeking and horizontal investment. However, in developing countries, labor redemption and human capital exert the greatest influence on FDI inflows; which shows characteristics of efficiency seeking and vertical investment.

• Korean Journal of Construction Engineering and Management
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• v.25 no.2
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• pp.36-44
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• 2024

This paper presents the application of Convolutional Neural Networks (CNNs) and Region of Interest (ROI) techniques for concrete crack analysis. Surfaces of concrete structures, such as beams, etc., are exposed to fatigue stress and cyclic loads, typically resulting in the initiation of cracks at a microscopic level on the structure's surface. Early detection enables preventative measures to mitigate potential damage and failures. Conventional manual inspections often yield subpar results, especially for large-scale infrastructure where access is challenging and detecting cracks can be difficult. This paper presents data collection, edge segmentation and ROI techniques application, and analysis of concrete cracks using Convolutional Neural Networks. This paper aims to achieve the following objectives: Firstly, achieving improved accuracy in crack detection using image-based technology compared to traditional manual inspection methods. Secondly, developing an algorithm that utilizes enhanced Sobel edge segmentation and ROI techniques. The algorithm provides automated crack detection capabilities for non-destructive testing.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.577-586
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• 2018

In this study, traffic safety technology was developed for rural areas by reviewingthe relevant literature and data from the Traffic Accident Analysis System for the Chungcheong region.The goal is to reduce traffic accidents in small regional cities and rural areas in Korea. A road shoulder recognition light was developed to fit the pedestrian characteristics of the people using transportation in rural areas. It also minimizes damage to crops due to light pollution from traffic lights and street lights, and it supplements problems of damage from collision with vehicles and agricultural machines. The efficiency of the technology developed in this study was verified by comparing and analyzing the number of traffic accidents and the saved cost before and after its installation. A test bedwas established based on rural areas and is being evaluated for its applicability and effectiveness. It is expected that the reliability of such facilities could be improved through continuous studies, data collection, and analysis.

• International Journal of Highway Engineering
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• v.14 no.2
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• pp.131-143
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• 2012

The past researches on roadway segment safety estimation focused on intersections, which are the primary traffic accident regions. The past researches on roadway segments, However, analyzed the effects of certain factors on the traffic accident occurrence rate by organizing the individual geometric structures of the roads, and there is still a dearth of researches on the development of a traffic accident estimation model for rural roadway segments. Therefore, this research focused on rural two-lane and multilane roadway segments and developed traffic accident estimation models through the application of statistical techniques. This is required to explain such high frequency of zero counts in the traffic accident data. In this research, it was found that the Hurdle model is more suitable than the Poisson or negative binomial-regression model for explaining the excess zeros case. In addition, main variables were chosen to estimate their effects on traffic accident occurrence at rural roadway segments, and the safety at such rural roadway segments was estimated. In this research, it was assumed that there are different factors that affect the safety at two-way lane and multilane roadway segments, and a traffic accident estimation model was developed by dividing the two-way lane and multilane roadway segments.