The ship security accidents that occur in ships, at sea, and in ports have become increasingly more serious in recent years, and in particular, maritime terrorism and the abduction by pirates are emerging as an international problem. Accordingly, the International Maritime Organization implemented a measures to enhance ship security by adopting SOLAS Chapter 11-2, ISPS-code in 2004. In this study, it was investigated whether JDS-S4, a directional sound receiver developed for responding to ship security accident, has durability and safety suitable for ships. For the purpose, the conducted emission test (CE102) of the US military standard test (MIL-STD-461F) was performed, and it was confirmed that JDS-S4 satisfies the test conditions sufficiently.

Recently, air pollution from fossil fuels is at a serious level, and the IMO proposes to reduce greenhouse gas emissions by about 70% by 2050, and controls greenhouse gas emissions by applying the energy efficiency disign index(EEDI) to each ship type. In this study, the marine fuel oil viscosity of MGO, MDO, HFO and CGO according to the temperature change was compared and measured and the difference was analyzed. As a result, the viscosity of CGO was 3.32mPa·s, which was almost similar to MGO(3.40mPa·s) and MDO(3.51mPa·s) so it was judged that it could be used as a marine fuel, and it was found that there was a significant difference with HFO at P<0.01 there was.

Valves are widely used in various industrial fields, such as plants, vessels and shipbuilding. In particular, the performance of the valve is an important factor that can influence the performance of the entire system. Therefore, in this basic study to establish a national technical qualification in the domestic field of valve maintenance, demands for the fields of valves and major congruence were analyzed focusing on the industrial facility curriculum of Korea Polytechnics, and level-differentiated trial examinations were applied to relevant majors to standardize the developed valve tester. The trial examination result displayed that in the highest level of difficulty, in the medium level of difficulty and in the lowest level of difficulty, the pass rate was 0%, 17.86% and 39.29% respectively.

In this study, four types of water-heavy fuel oil hybrid emulsion oil were manufactured depending on the moisture content ratio in order to reduce exhaust emissions of heavy fuel oil(Bunder-C), which is necessarily used in vessels, power plants and boilers. The components of the manufactured emulsion oil were analyzed using the ISO standard testing method. The analysis result showed that in the EM25 fuel with a maximum moisture content ratio of 25.0%, the moisture content was 25.0%, the sulphur content was 0.20%, the kinematic viscosity was 144.8mm2/s, the specific gravity was 0.9382, and the flash point was 100 Celsius degrees or above.

Recently air pollution is becoming a global environment issue. Especially, the smoke from engines and boiler systems, which burn fossil fuels directly, is an extremely serious issue. For this reason, IMO is tightening regulations for the control of NOx and SOx. Therefore, in this study, the NOx reduction effect of emulsified oil mixed with 10% of water was tested after applying the emulsified oil to an industrial boiler burner using Bunker-C oil. The study showed that the exhaust gas oxygen concentration of emulsified oil was nearly 1.3% high and this was identified by the effect of dissolved oxygen contained in water. Also, based on the standard oxygen concentration(4%), the average and maximum NOx reduction rates were 28.53% and 30.23% respectively, which means the reduction efficiency was very high.

목 적: 본 연구는 안경테 소재용 셀룰로오스 아세테이트(Cellulose Acetate; CA)의 최적 가공조건을 규 명하여 안경테 전용 가공기의 설계조건 선정에 활용하고자 한다. 방 법: CA안경테 소재의 가공성 평가를 위해 절삭력, 표면조도 및 형상, 칩 형상 등을 분석하였다. 절삭 속도와 이송속도를 가공변수로 다양한 실험을 수행하여 적정 가공조건을 선정하였다. 결 과: CA안경테의 반경방향 절삭력은 절삭속도에 변화에 따른 영향이 미미한 반면, 이송방향 절삭력은 20,000과 30,000 rpm에서 증가하는 경향을 보였다. 표면조도는 날당 이송이 작은 0.05 mm 경우 절삭속도가 증가하면서 양호해지는 결과를 얻었다. 결 론: 안경테 소재용 CA의 가공성을 절삭력과 가공면의 상태를 고려하여 평가하였다. 절삭력을 고려했을 때 절삭속도가 25,000 rpm이 가장 적정한 조건으로 나타났다. 표면조도를 고려했을 경우에는 저 날당 이 송, 고 절삭속도가 최적 가공조건이었다. 따라서 이를 종합했을 때 절삭력은 전체적으로 낮은 값을 가지므로 표면조도를 주요 인자로 고려하여 날당 이송 0.05 mm, 절삭속도 20,000~ 30,000 rpm이 적정 가공조건으 로 나타났다.

The perturbation of the steady state of reactive oxygen species due to biotic and abiotic stresses in a plant could lead to protein denaturation through the modification of amino acid residues, including the oxidation of methionine residues. Methionine sulfoxide reductases (MSRs) catalyze the reduction of methionine sulfoxide back to the methionine residue. To assess the role of this enzyme, we generated transgenic rice using a pepper CaMSRB2 gene under the control of the rice Rab21 promoter with/without a selection marker, the bar gene. A drought resistance test on transgenic plants showed that CaMSRB2 confers drought tolerance to rice, as evidenced by less oxidative stress symptoms and a strengthened PSII quantum yield under stress conditions, and increased survival rate and chlorophyll index after the re-watering. The results from immunoblotting using a methionine sulfoxide antibody and nano-LC-MS/MS spectrometry suggest that porphobilinogen deaminase (PBGD), which is involved in chlorophyll synthesis, is a putative target of CaMSRB2. The oxidized methionine content of PBGD expressed in E. coli increased in the presence of H2O2, and the Met-95 and Met-227 residues of PBGD were reduced by CaMSRB2 in the presence of dithiothreitol. An expression profiling analysis of the overexpression lines also suggested that photosystems are less severely affected by drought stress. Our results indicate that CaMSRB2 might play an important functional role in chloroplasts for conferring drought stress tolerance in rice

Nitrate contamination of water environments can create serious problems such as eutrophication of rivers. Conventional biological processes for nitrate removal by heterotrophic denitrification often need additional organic substrates as carbon sources and electron donors. We tried to accelerate biological denitrification by using bioelectrochemical reactor (BER) in which electrode works as an electron donor. Denitrification activity of 8 environmental samples from various sediments, soils, groundwaters, and sludges were tested to establish an efficient enrichment culture for BER. The established enrichment culture from a soil sample showed stable denitrification activity without any nitrite accumulation. Microbial community analysis by using PCR-DGGE method revealed that dominant denitrifiers in the enrichment culture were Pantoea sp., Cronobacter sakazakii, and Castellaniella defragrans. Denitrification rate (0.08 kg/m3·day) of the enrichment culture in BER with electrode poised at -0.5 V (vs Ag/AgCl) was higher than that (2.1×10-2kg/m3·day) of BER without any poised potential. This results suggested that biological denitrification would be improved by supplying potential throughout electrode in BER. Further research using BER without any organic substrate addition is needed to apply this system for bioremediation of water and wastewater contaminated by nitrate.

This study was carried out to develop an efficient process for the elimination of phenol pollutant from soils. An microwave-assisted process (MAP) and a conventional Soxhlet extraction method (SEM) were employed to extract phenol from two types of soils. The effects of extraction methods, aged time of the spiked soil samples, extraction solvent and extraction time on the extraction performance were compared. Our results demonstrate that the recoveries from standard soil spiked were at least 10% higher for MAP than those for the conventional Soxhlet. The extraction time by MAP requires significantly shorter time (1 min) than 18 h of the conventional Soxhlet. The recoveries from non-contaminated soil spiked with phenol were also almost identical for above results. The reduction of the extraction times with efficiency higher than that afforded by the conventional Soxhlet technique supports the suitability of the MAP method.