• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.4
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• pp.26-37
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• 2020

This study intends to present a fragility analysis method suitable for concrete cable-stayed bridges by performing an analysis reflecting design criteria and material characteristics from the results of inelastic time-history analysis. In order to obtain the fragility curve of the cable-stayed bridge, the limit state of the main component of the cable-stayed bridge is determined, and the damage state is classified by comparing it with the response value based on inelastic time history analysis. The seismic fragility curve of the cable-stayed bridge was made by obtaining the probability of damage to PGA that the dynamic response of the vulnerable parts to input ground motion would exceed the limit state of each structural member. According to the pylon's fragility curve, the probability of moderate damage at 0.5g is 32% for the longitudinal direction, while 7% for the transversal direction, indicating that the probability of damage in the longitudinal direction is higher in the same PGA than in the transversal direction. The seismic fragility curve of the connections showed a very high probability of damage, meaning that damage to the connections caused by earthquakes is very sensitive compared to damage to the pylon and cables. The cable's seismic fragility curve also showed that the probability of complete damage state after moderate damage state gradually decreased, resulting in less than 30% probability of complete damage at 2.0g.

• Journal of Korean Society of Forest Science
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• v.107 no.4
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• pp.378-384
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• 2018

Chinese jujube (Ziziphus jujuba Mill.), a member of family Rhamnaceae, is an economically important species. It has high nutritional value in fruits, and its medicinal properties have led to extensive use in traditional oriental medicine. In this study, we investigated the genetic characteristics of 270 jujube germplasms collected from the six major jujube fruit production areas in Korea including Boeun and Gyeongsan, in order to understand the current situation on cultivated varieties of domestic jujube and to obtain useful data for selection of superior germplasms and establishing their breeding plans. The results of ISSR marker analysis revealed that the Shannon's information index of the 270 germplasms was 0.107 and the genetic similarity was as high as 0.935 showing the dominance of a specific cultivar or germplasm, and almost 67% (180) of them were identified at the same genotype with 'Bokjo'. The domestic commercial jujube populations could be characterized by very low genetic diversity and thus may be vulnerable to external disturbances. In addition, it seems that most of the jujube fruits in domestic market were largely produced through parthenocarpy.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.36 no.3
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• pp.173-184
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• 2023

Presently, the general seismic fragility evaluation method for a bridge system composed of member elements with different nonlinear behaviors against strong earthquakes has been to evaluate at the element-level. This study aims to develop a system-level seismic fragility evaluation method that represents a structural system. Because the seismic behavior of bridges is generally divided into transverse and longitudinal directions, this study evaluated the system-level seismic fragility in both directions separately. The element-level seismic fragility evaluation in the longitudinal direction was performed for piers, bridge bearings, pounding, abutments, and unseating. Because pounding, abutment, and unseating do not affect the transverse directional damages, the element-level seismic fragility evaluation was limited to piers and bridge bearings. Seismic analysis using nonlinear models of various structural members was performed using the OpenSEES program. System-level seismic fragility was evaluated assuming that damage between element-levels was serially connected. Pier damage was identified to have a dominant effect on system-level seismic fragility than other element-level damages. In other words, the most vulnerable element-level seismic fragility has the most dominant effect on the system-level seismic fragility.

• Korean Security Journal
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• no.41
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• pp.293-326
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• 2014

Piracy is a worldwide issue, but the deteriorating security situation in the seas off Somalia, the Gulf of Aden and the wider Western Indian Ocean between 2005 and 2012 and in the increasing number of attacks in the Gulf of Guinea are a major problem. The depth of concern for the problem internationally is amply demonstrated by the levels of co-operation and coordination among naval and other forces from several countries that have assembled in the west Indian Ocean region and the Gulf of Aden to escort ships carrying humanitarian aid to Somalia and to protect vulnerable shipping. Notwithstanding this unprecedented effort, the vast sea area in which the pirates now operate makes it difficult to patrol and monitor effectively, particularly with the limited resources available. More resources, in the form of naval vessels and aircraft, are needed and at every opportunity the IMO encourages Member Governments to make greater efforts to provide the additional naval, aerial surveillance and other resources needed through every means possible. IMO provide interim guidance and recommendations to be taken into account when considering the use of PCASP(privately contracted armed security personnel) if and when a flag State determines that such a measure would be lawful and, following a full risk assessment, appropriate. The interim guidance and recommendations of IMO are not intended to endorse or institutionalize the use of armed guards. Therefore, they do not represent any fundamental change of policy by the Organization in this regard. It is for each flag State, individually, to decide whether or not PCASP should be authorized for use on board ships flying their flag. If a flag State decides to permit this practice, it is up to that State to determine the conditions under which authorization will be granted. Therefore, Korea should be introduced rationally PCASP for safe shipping. PCASP on board ships is much the same to special guard personnel of security services industry act. Act plan of Oceans and fisheries ministry on PCASP collides with special guard personnel system of National Police Agency. Rather than new law making, PCASP regukations have to be included in security services industry act. Management Agency of PCASP is to not Oceans and fisheries ministry, but Central Headquarters Korea Coast Guard of Public Safety and Security Ministry because of specialty and closely connection.