• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.330-331
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• 2018

It's prohibited to take sand from southeastern EEZ(Exclusive Economic Zone) from January 2017 in korea. So, the supply of sea sand has been decreased and costs of sea sand are rising as a result in the southeast region. This paper deal with appropriateness of the taking sea sand, circumstance and fisheries damages by extraction of EEZ sand and proposed control measures for ensuring quality of sea sand and consider fishermen support plan for ensuring a stable supply of sand in southeast region of korea.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2013년도 추계학술대회 논문집
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• pp.699-705
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• 2013

This paper presents vibration testing, control, and finite element analysis of a piping system, which is subjected to the changes in fluid levels. Nuclear power plants typically employ a cooling system that uses sea water. These systems are subjected to dynamic characteristic changes caused by sea-level variations, which introduces failures of cooling system components. Therefore in this study, analytical and experimental studies were performed to understand the effect of sea-level changes on the dynamic characteristics of piping systems. It was shown that, as the sea-level increases, pipe's natural frequencies decreases in relation to its mode shape. A 1/14 scale model was also built to compare the results obtained by the analytical study. A good agreement between experiment and analytical studies were observed. Finally, an on-line resonant frequency identification system was proposed and developed, which utilizes piezoelectric transducers as sensors and actuators, in order to avoid catastrophic failure of piping systems.

• 수산해양기술연구
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• 제50권4호
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• pp.542-550
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• 2014

We investigated biomass, diatom species and fucoxanthin contents as cell growth, fatty acid and amino acid contents as nutritional composition of diatoms attached on plate to confirm effects of light emitting diodes (LEDs) due to block off natural light. In the single LED irradiation, biomass showed significantly higher to $30.0{\pm}6.48mg/m^2$ in white LED than that of others (P<0.05). The dominate diatom species was Navicula cancellata. Their lipid contents showed significantly higher to $112.9{\pm}19.23ug/mg$ dry matter (DM) in control than that of others LEDs. But eicosapetaenoic acid (EPA) contents showed significantly higher to $3.3{\pm}0.62ug/mg$ DM than others, but not significantly differed with natural control light treatment (P<0.05). And total protein contents are higher in control and blue LED light than that of others, but essential amino acid contents showed significantly higher to $3.2{\pm}4.8%$ in control (P<0.05). In mixing light with natural and LED light, biomass showed $2.6{\pm}0.22mg/m^2$ in blue LED (P<0.05). Fatty acids contents were not significantly differed with all treatments. Amino acid contents showed to $11.0{\pm}0.33ug/mg$ DM in white LED (P<0.05), but not significantly differed with others LED lights (P>0.05). Therefore, we could suggest that irradiation of blue LED in natural light very benefit to diatom culture for larvae of sea cucumber and abalone and do on.

• 동아시아식생활학회지
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• 제20권3호
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• pp.372-381
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• 2010

This study was designed to examine the effects of sea buckthorn (SBT) on the plasma blood glucose and cholesterol level in diabetic rats. Diabetes mellitus was induced in male Sprague-Dawley rats weighing 200~220 g by an injection of streptozotocin (STZ) dissolved in a citrate buffer into the tail vein at a dose of 45 mg/kg of body weight. Sprague-Dawley rats were fed an AIN-93 recommended diet and the experimental groups were fed a modified diet containing 10% and 20% of SBT powder for 4 weeks. The experimental groups were divided into 6 groups which consisted of normal (N)-control group, N-SBT 10% and N-SBT 20% treated groups, STZ-control, STZ-SBT 10% and STZ-SBT 20% treated groups. The rats' body weight, aminotransferase activities and hematocrit (Hct) values were measured along with plasma levels of blood glucose and cholesterol. Body weight losses were observed by diabetic groups While the nondiabetic rats gained weight. There were significant differences between the control group and the diabetic groups in the weight of kidney. Aspartate aminotransferase activity was lower in the non-diabetic group compared to diabetic experimental groups. The blood glucose were significantly decreased in the 10% SBT of diabetic group. The cholesterol level of STZ-SBT 10% and STZ- SBT 20% were significantly lower than for the STZ-control group. These results show that the supplementation of sea buckthorn leave powder may have favorable influence on reducing blood glucose and cholesterol level in STZ-induced diabetic rats.

• Environmental Analysis Health and Toxicology
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• 제20권4호통권51호
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• pp.333-341
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• 2005

In order to know whether polychaetes could be used as an appropriate organism for the detection of genotoxicity, DNA strand breaks were evaluated in blood cells of a nereidae worm (Perinereis aibuhitensis) exposed to various aquatic chemical pollutants (e.g. Cd, Pb, Pyrene, Benaor[a]pyrene). Hydrogen peroxide increased DNA strand breaks up to the highest concentration (10 $\mu$M). Higher concentration than 0.1 $\mu$M showed a significantly more DNA damage than control. Cadmium and lead also showed higher DNA damage than control, over 1.0 and 1 $\mu$g/L, respectively. In case of pyrene, DNA damage was detected even at 0.001 $\mu$g/L. However, DNA damage decreased due to apoptosis at the highest concentration of pyrene and Pb. This study suggested that the polythaetous blood cells could be used effectively for screening genotoxic contaminants in the environment.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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• pp.1027-1030
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• 2006

Development of diurnal warming in the open Okhotsk Sea during the daytime and calm conditions was studied using sea surface temperature (SST) fields retrieved from NOAA AVHRR, Terra and Aqua MODIS, Aqua AMSR-E and ADEOS-II AMSR data. Sea surface wind fields were estimated from AMSR-E/AMSR measurements as well as were obtained from QuikSCAT scatterometer. Weak winds and cloudless conditions were observed in the central area of anticyclone, which moved slowly on 28-30 June 2003 east off Sakhalin. The area where the amplitude of the diurnal SST signal ${\Delta}T$ was significant also shifted slowly and had or circular or elongated shape. The ${\Delta}T$ was estimated relative to the SST values in the areas surrounding the centre of anticyclone where wind speed W exceeded 5- 6 m/s. The diurnal variations of SST, day-night differences were computed using NOAA-12 and NOAA-16 AVHRRderived data. Analysis of simultaneous SST and W fields showed that the increase of W from 0 to 5-6 m/s causes the decrease of ${\Delta}T$ to zero. Maximum warming exceeded $8^{\circ}C$ and was observed in the centre of anticyclone where W = 0 m/s. So strong heating was likely due to the increased chlorophyll a concentration in the area under study that follows from analysis of satellite ocean colour data.

• 한국해양공학회지
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• 제14권3호
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• pp.1-10
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• 2000

In order to effective manage the construction, disaster prevention plan and the harbor tranquility control, meteorological and sea-state characteristics around Cheju Island have been analyzed. Using results and damage examples of the port facilities under severe sea conditions, a reasonable construction control plan considering the regional characteristics of the sea-state and winds was proposed. That is, in northern part of Cheju Island, the construction work is affected mainly by the winter storms, while the typhoon mainly affects the southern part port facilities during summer to Autumn. Considering their typical characteristics, it is strongly suggested that the main construction work should be carried out during April to July in the northern part, and it should be made during October to next July in the southern part of the island. A permeable TTP mounded breakwater was constructed to protect severe waves as a temporal structure under the long-term development plan in Sogipo port. The transmission characteristics of the structure was discussed using the experimental results. The results show that the transmission coefficient $K_{t}$ is over 20% of incident waves, which cause many problems in the cargo handling in relation to harbor tranquility. In conclusion, this kind of permeable structure can be used only as a temporal structure for the disaster prevention under the construction process. It causes many problems in harbor tranquility if it is used as a permanent harbor structures.s.

• 한국항공운항학회지
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• 제19권3호
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• pp.43-53
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• 2011

It is well known some Foreign aircraft used to fly INCHEON FIR(Flight Information Region), especially the island of IEODO without a flight plan, even though foreign aircraft is subject to submitting a flight plan to Flight Information Center(FIC) before its flight. IEODO is a sunken rock 4.6m beneath the sea level, 149km away from Marado. Facing the Yangtze river's sea entrance horizontally and military zones of Korea and China vertically, IEODO is a very important place for national security of North East Asia because it is located at the boundary between China East Sea and Yellow Sea of South Korea. Moreover, JDZ(the 7th mine lot) is just 77NM from IEODO, which possesses natural gas eight times bigger than the gulf region and oil 4.5 times bigger than that of the U.S. In addition, INCHEON FIR, managed by MLTM(Air Traffic Control Center) and Japanese Self-Defense Force's JADIZ(Japanese Air Defense Identification Zone) are overlapping on IEODO whose air space is very complex. This paper focuses on air space, FIR, ADIZ(Air Defense Identification Zone) and related airspace system and suggests strategic implications of how to prevent foreign aircraft from invading INCHEON FIR without permission and of how to utilize the airspace efficiently.

• 한국어병학회지
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• 제22권2호
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• pp.163-166
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• 2009

The ectoparasite ciliate Trichodina has been recorded from above 100 species of freshwater and marine fishes. In April 2009, we investigated the trichodia infection in 13 species of marine fishes captured by emplacement net and gill net in order to understand trichodina infection status among the natural fish populations along the Namhae-Gun coast area, the southen coast of Korea. Trichodina infection was observed in 10 out of 10 sea basses Lateolabrax japonicus, 2 out of 5 finespotted flounder Pleuronichthys cornutus and 1 out of a stone flounder Kareius bicoloratus. The sea bass infected with the parasite showed hypertrophy and exfoliation in gill epithelium. In addition, hyperplasia and lamellar fusion of gill filament were noticed among naturally affected sea bass.

• 한국항만학회지
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• 제12권1호
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• pp.95-104
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• 1998

Water pollution in a semi-enclosed sea area such as a bay due to stagnancy of water has been a serious water environmental problem. Recently, some kinds of new methods to activate the tidal exchange between an inner bay and an outer sea area by control of a tidal residual current have been proposed. However, these methods have several problems, that is, I). deterioration in a natural view due to building of huge structures, II). increase of risk of navigation in case of a submerged structure, III). limition of sea area where a tidal current can be controlled and IV). difficulty in removing those structures in case of occurrence of an unexpected impact on water environment. In this paper, a new method is proposed, which can solve all the above problems, to purify water quality in a semi-enclosed bay by creation and control of a pattern of a tidal residual current. The tidal residual current is controlled by unsymmetric structures, which change the properties of resistance according to the direction of flow, arranged on the sea bottom. In this study, several numerical and hydraulic experiments of tidal current and particle-tracking for various arrangements of bottom roughness in a semi-enclosed model bay were carried out. As a result of experiments, it becomes clear that it is possible to generate a new tidal residual current and to activate a tidal exchange by only operation of bottom roughness arrangement.