• Journal of Korean Society of Coastal and Ocean Engineers
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• v.26 no.2
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• pp.81-95
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• 2014

In the present study, the statistical analysis on the storm waves in the East Sea have been carried out, and the several storm waves were reproduced by the modified WAM as a first step for the accurate and prompt forecasting and warning against the swell waves in East Sea. According to the present study, the occurrences of the storm waves from the North were the most probable, while the waves from the Northeast were most frequently observed. It was found that the significant wave heights of storm waves from the North and Northern northeast were larger than those of storm waves from the Northeast. But due to long fetch distance, the significant wave periods of storm waves from the Northesast were longer than those of North and Northern northeast. In addition to the wave analysis, the numerical experiments for the storm waves in East Sea were carried out using the modified WAM, and three periods of storm waves in 2013 were calculated. The numerical results were well agreed with wave measurements. However the numerical simulation results in shallow water region showed lower accuracies compared to deep water, which might be due to lower resolution of wind field and bottom topography caused by large grid size, 5 minute, adopted in the present study. Overall computational efficiency of the modified WAM found to be excellent compared to original WAM. It is because the modified WAM adopted the implicit scheme, thereby the present model performed 10 time faster than original WAM in computation time.

• Journal of the Korean Association of Geographic Information Studies
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• v.16 no.4
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• pp.91-105
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• 2013

This study performed an assessment of wave power potential in the Kangwon and Dongnam regions encompassing the East Sea and part of South Sea. Annual electricity production and economic effects of 28 wave energy converters with 750kW capacity were analyzed using significant wave height and peak wave period data(created from the NOAA's NWW3 model) and InVEST software(developed by Stanford University and University of Minnesota). Annual electricity production was estimated to be up to 1,207MWh/year and at least 163MWh/year. The spatial pattern of annual electricity production showed that the sea far from land has higher wave power potential than the sea near coast. The net present value(NPV) of 28 wave energy converters was calculated by considering an operation period of 25 years. When assuming that the electricity produced from wave energy converters is transferred to onshore power plants through underwater cables, the NPV was estimated to be up to 5,883USD(6,600,000KRW) and at least -63,494USD(-71,000,000KRW). In contrast, the NPV increased up to 28,095 USD(31,600,000KRW) when assuming that the electricity is utilized in the Ulleungdo and Dokdo. In addition, it was found that the break-even line of NPV in the East Sea becomes closer towards the land according to the increment of electricity price. The NPV of wave energy converters near the Ulleungdo and Dokdo will be 88,158 USD(99,000,000KRW) if the increment of electricity price is 100KRW.

• Journal of Biomedical Engineering Research
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• v.21 no.3 s.61
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• pp.239-246
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• 2000

In this paper. we propose a semi-automatic segmentation algorithm to extract organ in 3D medical data by using a manually segmentation result in a sing1e slice. Generally region glowing based tracking method consists of 3 steps object projection. seed extraction and boundary decision by region growing. But because the boundary between organs in medical data is vague, improper seeds make the boundary dig into the organ or extend to the false region. In the proposed algorithm seeds are carefully extracted to find suitable boundaries between organs after region growing. And the jagged boundary at low gradient region after region growing is corrected by post-processing using Fourier descriptor. Also two-path tracking make it possible to catch up newly appeared areas. The proposed algorithm provides satisfactory results in segmenting 1 mm distance kidneys from X-rav CT body image set of 82 slices.

• Journal of Wetlands Research
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• v.23 no.2
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• pp.107-115
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• 2021

In order to analyze wave propagation, tidal current, and sediment transport in the vicinity of the Gaeya open channel, it was classified into before(CASE1W) and after(CASE2W) installation of various artificial structures, and the calculation results for CASE1W and CASE2W were compared. For wave propagation, the results of incident and reflected waves were derived using the SWAN numerical model, and the tidal current velocity results were derived using the FLOW2DH numerical model for tidal current. The results of the SWAN numerical model and the FLOW2DH numerical model became the input conditions for the SEDTRAN numerical model that predicts sediment transport, and the maximum bed shear stress and suspended sediment concentration distribution near the Gaeya open channel were calculated through the SEDTRAN numerical model. As a result of the calculation of the SWAN numerical model, the wave height of CASE2W was increased by 40~50 % compared to CASE1W because the incident wave was diffracted and superimposed and the reflected wave was generated by about 7 km long northen jetty. As a result of the calculation of the FLOW2DH numerical model, According to the northen breakwater, the northen jetty and Geumrando, CASE2W was calculated 10~30 % faster than CASE1W in the tidal current of the Gaeya open channel. As a result of the calculation of the SEDTRAN numerical model, the section where the maximum bed shear stress is 1.0 N/m² or more and the suspended concentration is 80mg/L or more was widely distributed in the Gaeya open channel from the marine environment by the complex wave field(incident wave, reflected wave and tidal wave) and the installation of various artificial structures. it is believed that a sedimentation phenomenon occurred in the Gaeya open channel.

• Iberoamérica
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• v.22 no.2
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• pp.25-57
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• 2020

Eduardo Galeano is a left-wing intellectual who led the criticism and accusations of dictatorship and social absurdity in Latin America. It digs into the truth of hidden history that has not been revealed in official history. He values the memory of history to stop repetition of the unfortunate history of the past. The main research topic of this study, 『The Book of Embraces』, is also an extension of such work. Most of the stories in this work depend on the writer's memory. There is no coherence or integration in the content of the story, and the length of the text is not constant, so it is extremely informal and fragmented. This is a strategy to formally reveal the illogical and irrational reality of Latin America. He analyzes the problems of the separation system prevalent in Latin American society from various perspectives. It separates me and the others as well as the past and the present. It makes the memory of history void and paralyzes the consciousness of history. These systems are fixed for convenient governance. In this situation, the pattern of violence becomes more explicit and broad. The anxiety and fear of the Latin American public become commonplace. It is a reality of enduring daily life without hope. Galeano finds this enduring force in historical memory. He believes that when the past and the present meet and embrace, a new history of the future can be encountered. Galeano does not just criticize reality or cynical attitude but also suggests hope for the future.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.5
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• pp.505-511
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• 2023

In the present study, a deep learning model was established to predict the motion response of small fishing vessels. Hydrodynamic performances were evaluated for two small fishing vessels for the dataset of deep learning model. The deep learning model of the Long Short-Term Memory (LSTM) which is one of the recurrent neural network was utilized. The input data of LSTM model consisted of time series of six(6) degrees of freedom motions and wave height and the output label was selected as the time series data of six(6) degrees of freedom motions. The hyperparameter and input window length studies were performed to optimize LSTM model. The time series motion response according to different wave direction was predicted by establised LSTM. The predicted time series motion response showed good overall agreement with the analysis results. As the length of the time series increased, differences between the predicted values and analysis results were increased, which is due to the reduced influence of long-term data in the training process. The overall error of the predicted data indicated that more than 85% of the data showed an error within 10%. The established LSTM model is expected to be utilized in monitoring and alarm systems for small fishing vessels.

• Journal of the Korean Society for Environmental Technology
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• v.18 no.2
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• pp.165-172
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• 2017

In current stage, it is hard to predict the scale of damage caused by natural disaster and it is hard to deal with it. However, in case of disaster planning level, if it is possible to predict the scale of disaster then quick reaction can be done which will reduce the damage. In the present study, therefore, function of wind wave damage estimation among various disaster is developed. Damage of wind wave and typhoon in eastern and Jeju coastal zone was collected from disaster report (1991~2014) published by Ministry of Public Safety and Security and to reflect inflation rate, 2014 damage cost was converted. Also, wave height, wind speed, wave direction, wave period, etc was collected from Meteorological Administration and Korea Hydrographic and Oceanographic Administration web site. To reflect the characteristic of coastal zone when wave damage occurs, CODI(Coastal Disaster Index), COSI(Coastal Sensitivity Index), CPII(Coastal Potential Impact Index) published by Korea Hydrographic and Oceanographic Agency in 2015 were used. When damage occurs, function predicting wind wave damage was developed through weather condition, regional characteristic index and correlation of damage cost.

• Journal of the Korea institute for structural maintenance and inspection
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• v.13 no.6 s.58
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• pp.176-182
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• 2009

Other damage can occur due to the preexisting dull structure and installation of nonenvironmental-friendly concrete structure, lack of function for preventing coastal erosion. Increase of personal income and fast spread of the concept of waterfront casued the initiation of many project to improve aging coastal ports. However, none of environment-friendly structure has been developed and pre-existing solid block, igloo block, tunnel block are used commonly. In piers and lighter's wharf where the ships are mooring, resonance by the generation of a reflected wave caused by penetration wave in the port and port wave increases wave heights in the port and makes difficult to maintain the temperature, causes problems in mooring ships and cargo-working, and eventually increase the occurance of damages of the small ships by the collision. Therefore, development of new types of blcok is necessary. To apply Coastal Environments block developed for this reason, it requires allowable bearing capacity evaluation of shear key. For this study, we made test specimen for connecting part of C.E. Block, and conducted friction test of boundary surface. Data obtained by the experiment was analyzed by finite element analysis and assessed the coefficient of friction between C.E. Block and boundary surface.

• The Korean Journal of Quaternary Research
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• v.31 no.2
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• pp.31-42
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• 2017

Oahu Island is the third largest island of the Hawaiian chain which located in the northern hemisphere close to the center of the Pacific Ocean and is affected by storms and tsunamis in the northern and southern hemispheres. High-wave and high-energy waves are concentrated in the winter and summer, and the Oahu Coast is always in an active erosion environment. These natural effects are likely to become more severe with global warming and sea level rise. In addition, as the anthropogenic factors, there was indiscreet flood of development on the coast until the 1972 coastal management law was enacted. However, the present coastal erosion phenomenon was not serious than thought. The cause can be found in the improvement of the coastal management of the provincial government. The Hawaiian government is no longer applying this method, which was built prior to the enactment of the Coastal Control Act, due to increased erosion and side effects at other sites. So, in Hawaii, it is mainly applied to soft revetment methods such as supplying sand or making artificial sand dunes as an erosion prevention method. In Korea, there are some places where the soft revetment method is applied partially, but it is mainly composed of hard revetment structure.

• Korean Journal of Medicinal Crop Science
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• v.11 no.3
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• pp.246-251
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• 2003

Angiotensin converting enzyme(ACE) belongs to the class of zinc protease and plays an important role in the regulation of blood pressure. In this experiment, we investigated the inhibitory activities of ninety four plant extracts on ACE. The extracts were prepared by water and refluxing with 70% and 100% methanol. Among the extracts, two plant extracts such as Cassia tora, Persicaria cochinchinensis Kitagawa showed more than 60% inhibitory activities, and Foeniculum vulgare Gaertner, Scutellaria baicalensis Georgl, Caragana sinica (Buchoz) Rehder, Inula britannica var. chinensis showed $45.2{\sim}49.7%$ inhibitory activities. Twenty eight plant extracts such as Hemerocallis fulva L, Camptotheca acuminata Decne, Inula britannica var. chinensis, Xanthium strumarium, Polygonatum odoratum, Phellodendron amurense Rupr, Coix lachryma-jobi var. mayuen, Prunus ansu, Hibiscus mutabilis L, Thchosanthes kirilowii, Helianthus annuus, Juglans sinensis showed $30.3{\sim}39.7%$ Inhibitory activities. These results suggest that plant extracts which contain high ACE inhibitory activities may be useful as anti-hypertension agents and to the treatment of hypertension.