• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.5
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• pp.314-326
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• 2014

On 31 March 2007, the abnormal wave occurred along the western coast of Korea. In order to investigate the generation mechanism of abnormal waves and to understand the amplification process of the abnormal waves, the observed data were analyzed and one-dimensional numerical model experiments were performed by using both the linear shallow water equation and the linear Boussinesq equation models. Various types of pressure jump for the abnormal waves previously proposed by other researchers were reviewed. As a result, it was not possible to reproduce the abnormal waves from the previously proposed pressure jumps. In this study, we proposed a new form of pressure jump, and numerical simulations were performed in order to check the validity of the proposed pressure jump. The numerical results showed that the calculated period of abnormal waves and the maximum water elevations agreed reasonably well with those of the observations.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.12 no.1
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• pp.11-18
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• 2000

On the 25th of November in 1997 winter season, unprecedented high waves were recorded at the southern part of Korea Peninsular. The significant wave heights over 4 m were recorded at Marado, Pusan and Ulrungdo successively with time lags. Seoguipo breakwaters which were under construction were damaged by the unexpected high waves. These unprecedented southerly high waves in winter seem to be caused by unusual development and traveling of low pressure. Weather charts and wave fields calculated by a numerical model were analyzed to examine the unusual development of these waves. Protection against the southerly high waves in winter must be considered in coastal constructions and structures.

• The Journal of Internal Korean Medicine
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• v.42 no.4
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• pp.707-717
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• 2021

Objectives: The aim of this study was to introduce the normalization effects of stimulation of both ST36 and CV11, 12, 13 meridian points on the abnormal gastric myoelectrical activity in two cases of functional dyspeptic patients with gastric dysmotility. Methods: Gastric myoelectrical activity was recorded by electrogastrography every two weeks until their gastric myoelectrical activity finally reached the normality. Dominant frequency of gastric slow waves in the fasting and postprandial periods and a dominant power ratio were obtained on each occasion. Patients were treated three times each day: 9 am, 1 pm, and 7 pm. The first treatment consisted of manual and immersion stimulation on all used meridian points for 20 min. In the second and third treatments, electrical stimulation of both ST36 was added. It was conducted for 20 min at a strength intensity of 1.2 times the pain threshold at a frequency of 3 Hz. Results: Stimulation of the above meridian points normalized abnormal gastric myoelectrical activity. The time taken to return from abnormal gastric myoelectrical activity to normal was 16-19 weeks. Conclusion: Stimulation of both ST36 and CV11, 12, 13 meridian points normalized the abnormal gastric myoelectrical activity in the functional dyspepsia of gastric dysmotility.

• Atmosphere
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• v.18 no.4
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• pp.355-365
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• 2008

Synoptic and climatological characteristics of heat waves over Korea and Europe as well as their biometeorological impacts were compared. In July of 1994, excess deaths of about 2,388 in the population of South Korea are estimated by the modified excess death calculation algorithm ofKysely (2004). The excess deaths correspond to the net mortality increase of 12.5% in July of 1994 if we compare the estimated value to the expected number of deaths in this month (i.e., about 19,171). The comparative study of heat waves in Korea and Europe shows that the record-breaking heat waves in both regions are closely associated with prolonged droughts. In particular, reduction of soil moisture, precipitation and cloud cover and enhancement of insolation during the drought periods are very likely to be related to the increase in the intensity and the duration ofheat waves. Climate models predict that the frequency, intensity, and duration of heat waves in the 21 st century will be greatly enhanced in both areas. In order to reduce the biometeorological and socioeconomic impacts due to heat waves, not only the development of heat-related mortality prediction model that can be widely applied to many climate regimes, but also studies on the climatological association between extreme temperatures and abnormal hydrological cycle are needed.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2008.09a
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• pp.180-183
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• 2008

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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• 2008.09b
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• pp.180-183
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• 2008

• Journal of Industrial Convergence
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• v.21 no.8
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• pp.43-49
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• 2023

Since 2018, due to climate change, heat waves and cold waves have caused gradual damage to social infrastructure. Since the damage caused by cold weather has increased every year due to climate change in recent 4 years, the damage that was limited to a specific area is now appearing all over the country, and a lot of efforts are being concentrated from experts in various fields to minimize this. However, it is not easy to study real-time observation of sudden abnormal low temperature in existing studies to reflect local characteristics in discontinuously measured data. In this study, based on the weather-related data that affects the occurrence of cold-weather damage, we developed an algorithm pattern that can identify the time when abnormal cold temperatures occurred after searching for weather patterns at the time of cold-weather damage. The results of this study are expected to be of great help to the related field in that it is possible to confirm the time when the abnormal low temperature occurs due to the data generated in real time without relying on the past data.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2006.11a
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• pp.105-112
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• 2006

Freak waves in the ocean are recently drawing much attention as a natural disaster to ocean structures and navigating ships as well. Several observation data, among them the Draupner New Year Wave, show the very impressive feature of Freak waves whose wave height is up to three times as high as the significant wave height of surrounding waves, In addition, Freak wave appears as an isolated very high crest in somewhat stationary random waves of same order in their wavelengths. Bearing such characteristics in mind, one notices its extraordinary steepness. This strongly suggests that Freak wave is not long lived but transient nature on the whole. A great number of studies to explain these natures were published from both theoretical and numerical point of view. However it is not sure if they are applicable to actual ocean environment. In this paper, we deal with the results concerning abnormal and/or Freak waves from in-situ ocean wave data and point out several remarks to the problems lain behind the contributions in this context. A physical experiment is described to reinforce the subject discussed from the observation data.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.24 no.3
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• pp.217-227
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• 2012

On 31 March 2007, the abnormal wave occurred along western coast of Korean including Yeonggwang. In this paper, this event is studied using available field measurement data for the event analysis and numerical model for reproducing the unknown waves. We found several 1-min interval tidal elevation and mean sea level pressure (MSLP) data along the western coast of Korea and analyzed it using wavelet technique. We computed the arrival time and the propagation direction of abnormal wave using wavelet results and performed the numerical simulation using 2 dimensional shallow water wave model. The sea level under the forcing of air pressure jump was obviously amplified by the Proudman resonant effect. The computed sea levels compared with observations are underestimated, but the order of arrival time at the tidal station showed good agreement.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.11a
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• pp.165-166
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• 2020

The climate on the Korean Peninsula has been warmed recently, abnormal weather conditions such as heat waves, cold waves, and tropical nights have been detected frequently. Precisely, the number of days with cold waves in the winter has increased, and rapid changes of temperature in the morning and afternoon have occurred frequently in the 2000s. Due to the previous phenomenons, this research is focused on evaluating the concrete's Chloride Penetration Resistance and Durability, and the difference of the resistance according to the W/C.