4차 산업 혁명으로 해양산업은 해사 관련 기술 및 시스템, 특히 선원의 역할에 상당한 변화가 생길 것으로 예상됩니다. 특히, 자율운항선박(MASS)은 인적과실에 의한 안전사고의 예방과 해상 작업 환경의 개선을 위하여 개발되고 있습니다. IMO는 교육 및 훈련 분야를 포함한 모든 분야에서 MASS의 도입에 대한 준비작업을 하고 있습니다. 이에 반해 국내지정교육기관은 아직 MASS에 탑승할 선원을 육성하기 위한 자격기준이나 교육훈련에 대한 계획을 수립하지 못하고 있는 상황입니다. 따라서 본 논문은 MASS의 특성과 적용기술을 검토하고, AI, 빅 데이터, 사이버 보안 등 급변하는 기술 환경에 최적화될 수 있는 스마트 선원의 능력 및 교육 훈련에 대한 필요성을 제시하고자 한다.

We report the preparation of sulfonated reduced graphene oxide (SRGO) by the sulfonation of graphene oxide followed by radiation-induced chemical reduction. Graphene oxide prepared by the well-known modified Hummer's method was sulfonated with the aryl diazonium salt of sulfanilic acid. Sulfonated graphene oxide (SGO) dispersed in ethanol was subsequently reduced by γ-ray irradiation at various absorbed doses to produce SRGO. The results of optical, chemical, and thermal analyses revealed that SRGO was successfully prepared by γ-ray irradiation-induced chemical reduction of the SGO suspension. Moreover, the electrical conductivity of SRGO was increased up to 2.94 S/cm with an increase of the absorbed dose.

The electrochemical properties of novel metal powders were investigated for the electrode materias of polymer electrolyte memebrane electrolysis. Two types of Pt black and powder electrodes were hot-pressed on the polymer electrolyte membrane to form membrane electrode assembly. The galvanodynamic polarization methode was used to characterize the electrochemical properties of both electrodes. From the experimental results, we concluded that the powder electrode exhibits better electrochemical performance than Pt black as cathode material for the electrolysis.

Mn-Fe oxide and Mn-Fe oxide/(50wt%/50wt%) were prepared by ball milling method. XRD data of the prepared samples revealed that hematite and ferrite phase coexisted. Water splitting at 1273K, after thermal reduction at 1573K, was performed 4 times for the samples. Hydrogen production amount was analyzed by GC with TCD detector. Water splitting capacity of Mn-Fe oxide was improved by ball milling with .

NiTiZrSiSn bulk metallic glass powder was produced using inert gas atomization and then was sprayed onto a SS 41 mild steel substrate using the kinetic spraying process. Through this study, the effects of thermal energy of in-flight particle and crystallization degree by powder preheating temperature were evaluated. The deformation behavior of bulk metallic glass is very interesting and it is largely dependent on the temperature. The crystalline phase formation at impact interface was dependent on the in-flight particle temperature. In addition, variations in the impact behavior need to be considered at high strain rate and in-flight particle temperature.

The number concentrations and the water soluble ionic concentrations of PM2.5 have measured at Gosan site in Jeju, Korea, from March 2010 to December 2010, to clarify their characteristics. PM2.5 number concentrations vary from 22.57 to 975.65 particles/㎝3 with an average value of 240.41 particles/㎝3, which have been recorded evidently high in spring season as compared with those in other season. And the concentrations in small size ranges are greatly higher than those in large size ranges, so the number concentration in the size range 0.25∼0.45 ㎛ has more than 94% of the total number concentration of PM2.5. The major ionic components in PM2.5 are SO4 2-, NH4 + and NO3 -, which are mainly originated from anthropogenic sources, on the other hand, the concentrations of Cl-, K+, Ca2+ and Mg2+ are recorded relatively lower levels. The concentrations of the major ionic components are very high in spring season, but the concentration levels of the other components are recorded significantly high in winter season. On the other hand, in summer season, the lowest concentration levels are observed for overall components as well as the sum of them. The concentration ratios of nss-SO4 2-/SO4 2- and nss-Ca2+/Ca2+ are 98.1% and 88.9%. And the concentration ratio of SO4 2-/NO3 -(3.64) is greatly higher than the value in urban area due to no large NOx emission sources in the measurement. In addition, the correlation and the factor analysis for the number and the ionic concentrations of PM2.5 are performed to identify their sources. From the Pearson correlation analysis and the factor analysis, it can be suggested that the smaller parts(<0.5 ㎛) of PM2.5 is contributed by anthropogenic sources, but the sources of the remaining larger parts of PM2.5 are not able to be specified sources in this study.

The effects of the estrogenic compound 4-nonylphenol (4-NP) on vitellogenesis in juvenile olive flounder ( ) and rockfish ( ) exposed continuously at 10, 50 and levels for 7 days were compared. The expression of VTG mRNA level and protein using specific probes were examined. The levels of plasma estradiol-17 and testosterone (T) were assessed by radioimmunoassay (RIA). Plasma concentrations increased significantly in two female fish species exposed to of 4-NP over concentrations in control fish. Plasma T concentrations increased in . Four days after exposure, the level of VTG mRNA expression increased in and exposed to of 4-NP. In addition, plasma VTG protein expression was seen in and . In and exposed to 4-NP, the changes were noticed mainly in hepatocytic vaculation after 7 days of exposure. Thus, 4-NP may disrupt vitellogenesis in immature fish both directly and indirectly via disrupted steroidogenesis and liver pathology. Immature were the most sensitive to 4-NP exposure in vitellogenesis.

The aerosol number concentration have measured with an aerodynamic particle sizer spectrometer(APS) at Gosan site in Jeju, Korea, from March 2010 to March 2011. And then the atmospheric aerosol number concentration, the temporal variation and the size distribution of aerosol number concentration have been investigated. The aerosol number concentration varies significantly from 748 particles/㎝3 to zero particles/㎝3. The average number concentration in small size ranges are very higher than those in large size ranges. The number concentrations in the size range 0.25∼0.28 ㎛, 0.40∼0.45 ㎛ and 2.0∼2.5 ㎛ are about 84 particles/㎝3, 2 particles/㎝3 and 0.4 particles/㎝3, respectively. The number concentrations in range of larger than 7.5 ㎛ are below 0.001 particles/㎝3. The seasonal variations in the number concentration for smaller particle(<1.0 ㎛) are not much, but the variations for larger particle are very evident. And strong amplitudes of diurnal variations of entire averaged aerosol number concentration are not observed. Size-fractioned aerosol number concentrations are dramatically decreased with increased particle size. The size-fractioned aerosol number concentrations in size range 0.8∼4.0 ㎛ during nighttime are evidently higher than during daytime, but similar levels are appeared in other size range. The seasonal differences in the size-fractioned number concentrations for smaller size range(<0.7 ㎛) are not observed, however, the remarkable seasonal differences are observed for larger size than 0.7 ㎛.