• Journal of KSNVE
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• v.9 no.6
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• pp.1187-1192
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• 1999

The purpose of this study is to determine the most appropriate experimental method of the measurement of "damping loss factors" (DLF) for the statistical energy analysis(SEA) calculation. The successful prediction of vibration levels from the structure is critically dependent on the accurate estimation of DLF's not only in conventional vibration analysis but especially in SEA. Unforunately, calculation of accurate DLF is not an easy matter. So experimental methods are made use of for the DLF values. Three kinds of experimental methods for estimating DLF, i.e. decay rate method, half-power bandwidth method and power balance method, are presented and tests are carried out for the plate and the cylindrical shell examples. Pro and con of each methods is reviewed. Finally, calculated DLF values are used for vibration level estimation using commercial SEA software and compared with measured vibration data.tion data.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 1997.04a
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• pp.545-550
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• 1997

It is well known that Statistical Energy Analysis(SEA) is one of very attractive analytical methods to solve shipboard noise problems. With reasonable successes, many applications of SEA to shipboard noise prediction have been reported. However when one wishes to obtain theoretical predictions by using SEA in practical systems, he will find difficulty in modeling of source systems, that is, foundations where to place main engine, generator, compressor, and so on. Also, he will find that it is hard to determine the amount of power flow from machinery to structures. In this paper, SEA of a simple foundation model was carried out using the estimated amount of power flow from source; the estimated mobility method. The comparison between the estimated and measured results is presented. That comparison shows a method to get structure-borne noise power from the combination of machinery and foundation. This prediction method gave a good results for a air-compressor mounted on a model foundation. The method is expected to give a reasonable power output in practical problems.

• Proceedings of the KSR Conference
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• 2009.05b
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• pp.447-453
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• 2009

The interior noise of the High Speed Train(HST) is analyzed by applying the statistical energy analysis (SEA) method. The interior of each vehicle is divided lengthwise into nine cavities. Since the rolling noise and aerodynamics noise are expected to be dominant noise sources, they are treated as the noise sources in the model. To further simplify the model, curtains and seats are excluded. The simulation runs involving one-car, three-car and five-car trains are conducted. The maximum predicted noise level is 98.4dB. The results also show that the predicted noise levels are within 0.23% of each other. The results imply that it is not necessary to estimate the interior noise of the train by constructing multiple-car train models. The noise estimate based on just one-car train can be optimal with respect to the computational effort and modeling time.

• Parasites, Hosts and Diseases
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• v.24 no.1
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• pp.49-54
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• 1986

To evaluate the immature eggs of Paragonimus westermani as a source of diagnostic antigen, about a million eggs which were excreted by 104 adult worms were collected; their saline extract(soluble egg antigen; PwSEA) was prepared. The specific IgG and IgM antibody levels were observed in experimental dog paragonimiasis by micro ESISA, using PwSEA as well as whole worm extract of 12 week-old P. westermani(PwWWE). The protein composition of the PwSEA was observed by disc-PAGE. The results could be summarized as follows: 1. Specific IgG antibody to PwSEA begant to increase on 8 weeks after the experimental infection; it maintained its high level until the observation period of 13 weeks. The levels of IgM antibody to PwSEA however, did not show any significant change. 2. Specific IgG antibody to PwWWE began to increase earlier from 2 weeks after the infection and continued to increase until the observation period of 13 weeks. Its level was much higher than that to PwSEA. Specific IgM antibody to PwWWE increased temporarily during 2-8 weeks after the infection. 3. By disc-PAGE, PwSEA showed 2 protein bands of very low motility. The bands of PwSEA corresponded to the frist and second bands in the electrophoretic pattern of PwWWE of the 12 week-old worms. The above results indicated that the PwSEA induced antibody production in dog paragonimiasis, but its antigenicity was weaker than PwWWE to be used as a diagnostic antigen.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.3
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• pp.259-268
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• 2010

Data on squid catches by the Korean jig fishery in sea blocks ($30'{\times}30'$), water temperatures at depth(30m, 50m and 100m) and zooplankton biomass in the East Sea from 1980 to 1999 were analyzed to examine the mechanism of formation of the high density stock area. Japanese common squid (Todarodes pacificus) catch in the East Sea was low in 1980s, while the catch was high in 1990s. The five sea blocks (No. 76, 82, 83, 87, 88) of the southern part in the eastern coastal waters of Korea showed high levels of percentage of total catch (35.1%), whereas the four sea blocks (No. 65, 71, 72, 78) of the coastal waters of Uleung Island showed high levels of percentage of CPUE (61.2%) for 20 years. Squid catches showed monthly fluctuations according to the vertical distribution of optimum water temperature for fishing ($14^{\circ}C{\sim}19^{\circ}C$). High total catch and high CPUE area matched well with $10^{\circ}C$ isothermal lines at 100m depth indicating northern limiting of Tsushima Warm Current, and temporal and spatial change in $10^{\circ}C$ isothermal line caused the change in total catch and CPUE. Horizontal distribution of zooplankton biomass by sea block was not matched well with those of total catch and CPUE, however pattern of time-series change in total zooplankton biomass was similar to that in total squid catch.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3785-3791
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• 2012

Dissolved oxygen is one of the most important factors controlling growth in aquatic organisms. Hypoxia is generally defined as dissolved oxygen less than 2.8 mg $O_2/L$ (equivalent to 2 mL $O_2/L$ or 91.4 mM). Therefore, hypoxia zone can cause a serious problem in marine ecosystem. In this study, to investigate embryotoxic (fertilization and embryo development rates) effects of hypoxia on sea urchin Strongylocentrotus nudus were exposed to dissolved oxygen levels of 7.6 mg $O_2/L$ (normoxia) and 1.8 mg $O_2/L$ (hypoxia) for 2 days at $15^{\circ}C$ and 33 ‰. Also, Expression levels of stress related gene (HSP70) and antioxidant related gene (glutathione reductase) in the sea urchins exposed to hypoxia were confirmed by Immunoblotting and RT-PCR analysis. In results, we showed that developmental rates were dramatically reduced in hypoxia condition. Molecular analysis demonstrated that higher HSP70 (5.5 fold) and glutathione reductase gene (2.79 fold) were present in the sea urchin exposed to hypoxia. Our results suggested that hypoxia can cause the abnormal development and elicits a stress and antioxidant response on sea urchin.

• Food Science of Animal Resources
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• v.30 no.1
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• pp.55-61
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• 2010

Breakfast sausages containing 1, 2, 3, and 4% sea tangle powder (Lamina japonica) were prepared. No differences were found in moisture, protein, and fat contents among the control and treatments. However, the ash content increased with increasing amounts of sea tangle powder (p<0.05). The pH levels in the treated samples were lower than the control in both the meat batters and the breakfast sausages (p<0.05). The $L^*$ and $a^*$ values of the meat batters and breakfast sausages were decreased by the addition of the sea tangle powder, and the control had the highest $b^*$ value (p<0.05). The added sea tangle powder improved cooking loss and improved emulsion stability. The T4 sample (containing 4% sea tangle powder) was shown to have the lowest cooking loss and water loss (p<0.05). The hardness, gumminess, and chewiness of the treatments increased compared to the control due to the presence of dietary fibers in the sea tangle. In the sensory evaluations, the 1% sea tangle powder treatment received a lower color score, but received significantly higher scores for flavor, tenderness, and juiciness (p<0.05). Collectively, the breakfast sausage containing 1% sea tangle powder was determined to have the highest overall acceptability. Altogether, the best results, in terms of physicochemical and sensory properties, were obtained for the breakfast sausage containing 1% sea tangle powder.

• Preventive Nutrition and Food Science
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• v.5 no.4
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• pp.219-224
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• 2000

Dieary effects of sea tangle on immune functions were investigated in diabetic mice. Four groups of ICR mice weighing 33.36$\pm$1.01 g were fed either an AIN-76 diet only (control), or with additional sea tangle powder, sea tangle water extract, and alginate at the level of 13.6%, 4%, and 1%, respectively by weight. Cellulose was omitted in sea tangle powder and alginate diets. After 10 days of feeding respective experimental diets, all mice were made diabetic by five consecutive intramuscular injections of streptozotocin (40mg/kg body weight per day) and fed the diets for four more weeks. Plasma IgG concentrations but not those of IgM were significantly higher in mice fed sea tangle powder, extract or alginate than those on the control diet. Plasma TNF$\alpha$ levels were, however, lower in those fed sea tangle power or water extract than control and alginate fed groups. TNF$\alpha$ releases from macro phages isolated from four groups and cultured with 5 $\mu\textrm{g}$/mL LPS for 24 hors showed a similar tendency to the results of plasma concentrations in the respective groups, but IL-1$\beta$ releases were not different among four groups. Lymphocyte proliferation in response to LPS (10$\mu\textrm{g}$/mL) measured using splenocytes cultured for 3 days was highest in the alginate fed group (594$\pm$38%) and those of sea tangle powder (536$\pm$47%) and extract (547$\pm$34%) fed groups tended to be higher than the control (523$\pm$30%). It is concluded that sea tangle contains immunomodulatory components besides alginate that could enhance humoral immunity of itself. The immunomodulatory effects of sea tangle constituents is regarded as beneficial for diabetic subjects.

• Journal of the Korean earth science society
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• v.41 no.4
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• pp.323-343
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• 2020

Observation data measured at Ieodo Ocean Research Station (IORS) have been utilized in oceanographic and atmospheric studies since 2003. Sea level data observed at the IORS have not been paid attention as compared with many other variables such as aerosol, radiation, turbulent flux, wind, wave, fog, temperature, and salinity. Total sea level rises at the IORS (5.6 mm yr^-1) from both satellite and tide-gauge observations were higher than those in the northeast Asian marginal seas (5.4 mm yr^-1) and the world (4.6 mm yr^-1) from satellite observation from 2009 to 2018. The rates of thermosteric, halosteric, and steric sea level rises were 2.7-4.8, -0.7-2.6, 2.3-7.4 mm yr^-1 from four different calculating methods using observations. The rising rate of the steric sea level was higher than that of the total sea level in the case with additional data quality control. Calculating the non-steric sea level was not found to yield meaningful results, despite the ability to calculate non-steric sea level by simply subtracting the steric sea level from total sea level. This uncertainty did not arise from the data analysis but from a lack of good data, even though tide, temperature, and salinity data were quality controlled two times by Korea Hydrographic and Oceanography Agency. The status of the IORS data suggests that the maintenance management of observation systems, equipment, and data quality control should be improved to facilitate data use from the IORS.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.7 no.4
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• pp.289-304
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• 1995

Time series of the relative sea levels at the selected tide-gauge stations in the North Pacific and historical aerial photographs in the Hawaiian Islands are analyzed. Long-term rising trend of sea level ranges from +1 to +5 mm/yr at most of the stations, which is primarily due to global warming and tectonic motion of the plates. The annual and interannual fluctuations of sea level result from the thermal expansion/contraction of sea-surface layer due to the annual change of the solar radiation and possibly from a coupled ocean-atmosphere phenomenon associated with an ENSO event, respectively. Sea-level changes in three different time-scales (linear trend. annual oscillation, and interannual fluctuation) and their quantitative contribution to the shoreline changes as a result of long-term cross-shore sediment transport arc hypothesized.