PURPOSES : The objectives of this study are to evaluate the condition of concrete bridge decks using the multi-channel ground penetrating radar (GPR) testing and compare the value of its dielectric constant value with actual concrete condition. METHODS : The reflection coefficient method was used to measure the dielectric properties of concrete bridge decks. Air-coupled step-frequency GPR testing was used to measure the time taken for reflection from the interfaces between the layers. Specimens of the asphalt mixture and concrete bridge-deck were collected by field coring. GPR testing was conducted on two bridges with different concrete bridge deck conditions on national highways. After the GPR tests, the actual conditions of the concrete bridge deck were investigated using specimen coring. RESULTS : GPR testing indicated that the dielectric constants of concrete bridge decks in good condition ranged from 8 to 10, whereas those corresponding to poor condition ranged from 4 to 6. The results of GPR testing can determine the actual condition and degree of distress of concrete bridge decks determined from the specimen coring data. Therefore, GPR testing is appropriate for nondestructively evaluating the condition of a concrete bridge deck. CONCLUSIONS : The analysis results of the dielectric constants of the concrete bridge deck obtained from multichannel GPR testing were consistent with the actual bridge deck conditions. In the near future, an additional verification process for this approach under different bridge conditions will be required to improve its precision and ensure reliability.

Recently, the government has provided support such as entering new markets, expanding sales channels, and supporting manpower, not just in the form of funding, to efficiently and effectively support limited national resources to improve corporate performance. In this study, we tried to find out the effect of government support for companies that have benefited from the Excellent Technology Research Center Project (ATC Project) and the World Class 300 project using propensity score matching. As a result of the analysis, the effect of government support for the ATC project became visible after the appointment period, while the effect of the World Class 300 project was insignificant. This means that when the size of the company is small, the effect of government support is more pronounced. This suggests that in order to maximize the effectiveness of government support, appropriate national policy interventions such as government innovation funding are needed when the size of the company is small. In this study, differences in the timing, performance indicators, and company size of policy support effects were found in the growth stage of a company from a mid- to long-term time series perspective, suggesting that support policies based on this need to be adjusted and redesigned.

우리나라 해양환경에 유출되는 위험·유해물질(Hazardous Noxious Substances, HNS)의 해양환경 및 사회환경 영향평가 결과 와 HNS 확산 영역, 해양환경 정보, HNS 실태조사 결과 등 관련 연구 결과 및 자료를 정책결정자와 연구자들에게 공유할 수 있는 HNS 국내 용 플랫폼을 구축하고자 한다. 국내의 HNS 관리 및 배출 체계 마련을 위한 의사결정 지원이 가능하고 국내 실정에 적합한 플랫폼의 설계 를 위하여 유해물질의 데이터 관리 및 유출 시 대응 도구, 기초적인 정보 등 플랫폼에 관련된 기술동향을 분석하는 등 국내·외의 플랫폼 개발 사례를 고찰하였다. 유속 벡터의 전처리 기능 개발, 전처리 결과에 따른 동적 시각화 구현, 해양산업시설 배출 HNS의 유출량과 유출 범위의 전처리 모듈, HNS 해양환경 영향평가 연산 모듈 프로토타입을 개발하였다. HNS 해양환경 영향평가를 위한 국내용 HNS 플랫폼은 초기 위해성을 평가하고 대응 및 관련 법제화 시 과학적인 기초 도구로써 활용될 수 있을 것으로 기대된다.