어선과 같은 소형선박의 충돌사고는 큰 인명피해를 초래한다. 본 연구 이전에 선행된 연구에서는 충돌위험을 판단하고 경보를 발생시키는 소형선박 충돌예방 알고리즘을 개발하였다. 하지만 충돌경보와 같이 안전을 위해 제공되는 서비스는 위험을 예방할 뿐 아니라 이용자의 만족도 또한 어느 정도 수반되어야 효과적으로 기능할 수 있다. 본 연구에서는 소형선박 충돌예방 알고리즘의 실용성 향상을 위해 알고리즘을 개선하고, 알고리즘을 실제로 적용하여 개선결과 및 효과를 확인하고자 하였다. 충돌경보 서비스를 사용한 소형선박 운항자들을 대상으로 설문조사를 수행한 결과, 충돌경보의 정확도 향상과 경보 횟수 및 음량에 대한 사용자들의 요구사항이 확인되었다. 이에 따라 본 연구에서는 사용자 만족도 향상을 위해 알고리즘을 개선하였으며 실제 해상환경에서 개선된 알고리즘을 적용한 실선실험 을 수행하였다. 그 결과 개선 전보다 경보 발생 빈도가 감소하였지만, 위험한 상황에서는 경보가 비교적 꾸준히 발생하였으며, 충돌경보의 정확성과 실용성이 향상된 것으로 분석되었다. 추후에는 개선된 알고리즘의 적정성에 대한 근거자료를 마련하여 알고리즘의 실용성과 신뢰성을 확보한다면 소형선박 충돌사고 예방에 효과적으로 기여할 수 있을 것이다.

The demand for the revitalization of marine tourism in Busan North Port is increasing due to changes in functions such as an increase in harbor traffic volume and the expansion of marine leisure space in Busan. As a result, Busan City plans to set a phased alleviation target for prohibition of cruise ship operations, and to lift the prohibition of excursion ship operations in North Port following the cancellation of the prohibition of excursion ship operations in South Port in 2017. The purpose of this study is to evaluate the risk of excursion ship operations in Busan North Port by applying the marine traffic assessment index and to examine the possibility of excursion ship operations. For this purpose, port status, marine accidents, and traffic flow of Busan North Port were investigated. In addition, marine traffic assessment indexes, such as traffic congestion, risk based on an ES Model, and IWRAP MkII, a maritime risk assessment tool, were used to assess the risk and possibility of excursion ship operations in Busan North Port. This study can be used as basic data for analyzing the risk factors that may occur when excursion ships are operated in Busan North Port and to define how excursion ships should operate, with related safety measures.

Continuous outbreaks of Shigella spp. have raised concerns about the lack of rapid and on-site applicable biosensor method for Shigella detection. Since a bacteriophage has recently been employed as an emerging bio-recognition element in biosensor method, Shigella sonnei-specific bacteriophage was isolated and purified from a slaughterhouse with the final concentration of 2.0×1012 PFU/mL in this study. Analysis of purified S. sonnei-specific bacteriophage using transmission electron microscopy indicated that it possessed an icosahedral head with a relatively long non-contractile tail. It was therefore classified as a member of the Siphoviridae family. Head width, head length, and tail length were 69.9±11.2 nm, 77.5±8.8 nm, and 264.4±33.9 nm, respectively. The genomic DNA size of the S. sonnei-specific bacteriophage was determined to be approximately 25 kb by using 0.4% agarose gel electrophoresis. In specificity test with 43 food-associated microorganisms, the S. sonnei-specific bacteriophage exhibited a clear plaque against S. sonnei only. In addition, the S. sonnei-specific bacteriophage was stable within a wide range of pH values (pH 3-11) and temperatures (4-37 ). Thus, the present study demonstrated the excellent specificity and stability of the S. sonnei-specific bacteriophage as a novel bio-recognition element for S. sonnei detection in foods.

In this study, the antioxidant and anti-wrinkling effects of extracts from Aruncus diocius var. kamtschaticus (ADV) were investigated. According to the results, the ethanol extract has better antioxidant and anti-wrinkling effects than the water extract. The amounts of total polyphenol and flavonoid compounds in the ethanol extract were 122 and 36 mg/g, respectively, while those in the water extract were 87 and 26 mg/g. The antioxidant activities of the ethanol and water extracts were 395 and 4,682 μg/mL as the RC50 values for the DPPH radical scavenging activity, and 227 and 366 μg/mL for the ABTS+ radical scavenging activity, respectively. The reducing power of the ethanol extract (1.58 at 2 mg/mL) was higher than that of the water extract (0.88 at 2 mg/mL). The astringent activities of the ethanol and water extracts were 91.27 and 16.35% at 10 mg/mL, respectively. Furthermore, the ADV ethanol extract treatment of the fibroblast cell after UV irradiation resulted in increased cell viability (10% at 100 μg/mL) and collagen biosynthesis (33% at 100 μg/mL), with a lowering in the MMP-1 expression level (16.8 % at 100 μg/mL). These results demonstrate that AVD provides a remarkable and significant tensor and anti-wrinkling effect on the skin, which could be of a great use in anti-aging skin care products.

This study was carried out to get more operational characteristics of the sequencing batch biofilm reactors with media volume/reactor volume ratio of 15 %, 25 % and 35 %. Experiments were conducted to find the effects of the media packing ratio on organic matters and nutrients removal. Three laboratory scale reactors were fed with synthetic wastewater. During studies, the operation mode was fixed. The organic removal efficiency didn't show large difference among three reactor of different packing media ratios. However, from the study results, the optimum packing media ratios for biological nutrient removal was shown as 25%. The denitrifying PAOs could take up and store phosphate using nitrate as electron acceptor.

An evaluation of the application of SBR and biofilm on small sewerage system was conducted. A newly developed small sewerage system, using SBR, was successfully applied to the nutrient treatment using municipal wastewater. The system was consisted of 6 compartments. Two systems, with SBR (A type) or without SBR (B type), were compared by several parameters (COD, SS, T-N, NH4+-N, NO3--N, NO2--N, alkalinity, pH, DO) in all experimental periods. Also, the time variation of several parameters (DO, pH, NH4+-N, NO3--N, NO2--N) was examined in a SBR applied sewerage system. T-N removal efficiency of B type was higher than that of A type by the effect of nitrification and denitrification even though the COD removal efficiencies were similar. In aeration stage, the pH was decreased from 6.4 to 6.3 within 1 h and increased to 6.65 at the end of aerobic stage, and pH was decreased to 6.2 in non-aeration stage, and these phenomena were explained. The effects of nitrification and denitrification were compared in A type and B type sewerage system, and the typical nitrificaion and denitrification were observed in B type sewerage system.