• Journal of Ocean Engineering and Technology
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• v.26 no.2
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• pp.68-78
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• 2012

This study proposes an improved 3-D model that includes a new non-reflected wave generation system for oblique incident and multi-directional random waves, which enables us to estimate the effect of the various wave-types on 3-D wave fields in a coastal area with permeable submerged breakwaters. Then, using the numerical results,the three-dimensional wave field characteristics around permeable submerged breakwaters are examined in cases of oblique incident and multi-directional random waves. Especially, the wave height, mean surface elevation and mean flow around the submerged breakwaters are discussed in relation to the variation of incident wave condition.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2013.06a
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• pp.275-276
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• 2013

This analysis method is based on the wave pressure function with the continuity in the analytical region including fluid and porous structures. Wave profiles coming with oblique angle to permeable submerged breakwater on the porous seabed are computed numerically by using boundary element method. When compared with the existing results for the oblique incident wave, the results of this study show good agreement. The results indicate that wave profiles own high dependability regarding the change of oblique incident waves and permeable submerged breakwater on the porous seabed. Therefore, the analysis method of this study are estimated to be applied as an accurate numerical analysis referring to oblique incident waves and permeable submerged breakwater on the porous seabed in real sea environment.

• Journal of Korean Society of societal Security
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• v.4 no.1
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• pp.39-47
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• 2011

According to the current basic law of disaster and safety management, Standard Incident Command System is limited to Emergency Rescue Function, and Incident Commanders are only Fire Fighting Agencies. The main purpose of this study is to provide some suggestions to improve general-purpose of Standard ICS for various incidents. Also, there are some suggestions for Emergency Operation Centers as a coordinator and supporter of mobilizing response resources in all large scale disaster.

• International Journal of Naval Architecture and Ocean Engineering
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• v.11 no.1
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• pp.119-130
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• 2019

This paper establishes an iterative calculation model for the hydrodynamic performance of propeller in oblique flow based on low order potential based surface panel method. The hydrodynamic performance of propeller is calculated through panel method which is also used to calculate the induced velocity. The slipstream of propeller is adjusted according to the inflow velocity and the induced velocity. The oblique flow is defined by the axial inflow velocity and the incident angle. The calculation results of an instance show that the thrust and torque of propeller decrease with the increase of axial inflow velocity but increase with the incident angle. The unsteadiness of loads on the propeller blade surface gets more intensified with the increases of axial inflow velocity and incident angle. However, comparing with the effect of axial inflow velocity on the unsteadiness of the hydrodynamic performance of propeller, the effect of the incident angle is more remarkable.

• Anxiety and mood
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• v.19 no.2
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• pp.94-99
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• 2023

Objective : We assessed the effectiveness of a mindfulness-based intervention in improving positive psychological resources in older people who were affected by the Jeju 4·3 incident. Methods : This study included 25 older people recruited from the Jeju 4·3 Trauma Center. The intervention was conducted on a once-a-week basis for six weeks. All participants completed self-report questionnaires, including the Five Facet Mindfulness Questionnaire Short Form (FFMQ) and Positive Resources Test (POREST). Results : This intervention significantly improved the total score and the nonreactivity, observing, acting with awareness, describing, and nonjudging of inner experience FFMQ scores. The interventions also significantly improved the POREST subscale scores. Conclusion : The mindfulness-based intervention significantly improved positive psychological resources in older people exposed to the Jeju 4·3 incident.

• 한국ITS학회:학술대회논문집
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• 2003.11a
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• pp.286-291
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• 2003

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.6
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• pp.69-79
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• 2016

If the security incidents are occurred then, the company concentrates on the quick reaction to security incidents, reports the reason of incidents, it's problem, the result of measure to the top management team. There will be the case that actively finding problems and taking it's actions with linking the internal problems whenever external security incidents are occurred or that having only interest of problems at the moment. It is important that lasting the preventing action to prevent security incidents than not concentrating on only the security incidents are occurred. To do this, the systematical and consistent method for this should be provided. In this paper, we will provide a security incident forecast system. The security incident forecast system updates the incident induction factor which helping to forecast the potential security incidents on the database inferred from the direct security incidents which are occurred inside the company as well as the indirect security incidents which are occurred outside the company and makes interact with the incident experience and the measure process systematically. The security incident forecast system is the efficient measure about the potential security incidents in taking precaution.

• The Journal of the Acoustical Society of Korea
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• v.25 no.3E
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• pp.115-122
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• 2006

The bistatic scattering of an incident wave by a hemi-spherically capped cylinder is of particular interest because it has rarely been studied until the present day. The configuration of a hemi-spherically capped cylinder is similar to naval underwater weapons (submarines, mines, torpedos, etc.), but which is not exactly the same. This paper describes a novel laboratory experiment aimed at direct measurement of bistatic scattering by a hemi-spherically capped cylinder. Bistatic scattering by a hemi-spherically capped cylinder was measured in an acoustic water tank (5m long, 5m wide, 5m deep) using a high frequency projector (120kHz) and hydrophone. Measurements of monostatic scattering were also made under the same conditions. The bistatic scattering pattern by a hemi-spherically capped cylinder was measured against the incident angles $(0^{\circ},\;15^{\circ},\;20^{\circ},\;30^{\circ},\;45^{\circ},\;60^{\circ},\;90^{\circ})$ in order to verify various scattering pattern characteristics by the change of incident angle. The results indicate that the bistatic scattering TS at a wide scattering angle is much stronger than the mono static scattering TS. In bistatic scattering, the forward scattering TS is significantly stronger than the backward scattering TS, and the forward scattering pattern is also broader. In case of seven incident angles, the maximum value of forward scattering TS is about 14dB stronger than that of backward scattering TS. It is also found that forward scattering varies with the incident angle of sound to a much less extent than backscattering, and it is not seriously affected by the incident angle. These features could be the advantages of using forward scattering for detecting underwater targets at long range and increasing detection area and probability.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.9
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• pp.840-846
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• 2011

In this paper, reflection and RCS characteristic of the EGS(Electromagnetic Gradient Surface) due to incident angle and polarization is analyzed. Incident angle, ${\theta}_i$, is rotated from $0^{\circ}$ to $50^{\circ}$ with $10^{\circ}$ steps and perpendicular and parallel polarization of incident wave are also considered each incident angle. Reflection and RCS characteristic is not much affected by variation of polarization for normal incidence(${\theta}_i=0^{\circ}$). Reflection pattern has different characteristic due to variation of incident angle and polarization but the EGS has about 2 dB of RCS difference due to polarization in RCS characteristic.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.21 no.2
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• pp.154-163
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• 2009

Incident wave angles are conventionally estimated by the directional spectrum analysis of wave data collected from in-situ sensors. The in-situ measurements are limited in monitoring incident wave angles in the wide surf zone, since the techniques are typically expensive, labor-intensive, and point-measuring. In this study, estimation of incident wave angles using wave crest features captured in digital video imagery is proposed to observe incident wave directions over the surf zone. Line signatures of wave crests having high image pixel intensities are extracted by moving an interrogation window to identify high intensity pixels in sequential video images. Wave angles are computed by taking the first derivative of the extracted crest signatures, i.e. local slope of the crest signatures in the two-dimensional physical plane. Compared to the wave angle estimates obtained by the directional spectrum analysis, video-based wave angle estimates show good agreements in general.