• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.4
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• pp.83-91
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• 2021

In this study, to improve the connection performance between the existing reinforced concrete (R/C) frame and the strengthening member, we proposed a new H-section steel frame with elastic pad (HSFEP) system for seismic rehabilitation of existing medium-to-low-rise reinforced concrete (R/C) buildings. This HSFEP strengthening system exhibits an excellent connection performance because an elastic pad is installed between the existing structure and reinforcing frame. The method shows a strength design approach implemented via retrofitting, to easily increase the ultimate lateral load capacity of R/C buildings lacking seismic data, which exhibit shear failure mechanism. Two full-size two-story R/C frame specimens were designed based on an existing R/C building in Korea lacking seismic data, and then strengthened using the HSFEP system; thus, one control specimen and one specimen strengthened with the HSFEP system were used. Pseudodynamic tests were conducted to verify the effects of seismic retrofitting, and the earthquake response behavior with use of the proposed method, in terms of the maximum response strength, response displacement, and degree of earthquake damage compared with the control R/C frame. Test results revealed that the proposed HSFEP strengthening method, internally applied to the R/C frame, effectively increased the lateral ultimate strength, resulting in reduced response displacement of R/C structures under large scale earthquake conditions.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.5
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• pp.149-156
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• 2021

FRP has been proposed to replace the steel as a reinforcement in the concrete structures for addressing the corrosion issue. However, FRP-Rebar does not behave in the same manner as steel because the properties of FRP are different. For example, FRP-Rebar has a high tensile strength, low stiffness, and linear elastic behavior which results in a difference bonding mechanism to transfer the load between the reinforcement and the surrounding concrete. Therefore, bonding behavior between FRP-Rebar and concrete has to be investigated using the bonding test. So, Pull-out test has been used to estimate bond behavior because it is simple. However, the results of pull-out test have a difference with flexural-boding behavior of FRP-Rebar concrete member. So, it is needed to evaluate the real fleuxral-bonding behavior. In this study, the evaluation method to flexural-bonding behavior of FRP-Rebar concrete member was reviewed and compared. It was found that the most accurate evaluation method for the fleuxral-bonding behavior of FRP-Rebar concrete member was splice beam test, however, the size and length of specimen have to increase than other test method and the design and analysis of splice beam is complex. Meanwhile, characteristics of concrete could be reflected by using arched beam test, unlike hinged beam test which is based on the ignored change of moment arm length in equilibrium equation. However, the possibility of shear failure exists before the flexural-bonding failure occur.

• Journal of Climate Change Research
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• v.2 no.2
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• pp.115-131
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• 2011

Out of all the possible actions that can be taken to respond to greenhouse gas reduction, including development of greenhouse gas reduction technology, infrastructure, actions to improve energy saving and efficiency, and offset with carbon emission reductions (CERs), this study shall focus on the investment on CERs. This study will take a look at risks involved with investing in CERs such as UN registration refusal risk and CERs price fluctuation, and will design risk management model which shall be verified. The goal of this paper is to provide optimized CERs investment strategies for different types of investors, such as general trading companies seeking for investment opportunities and financial companies with plans for green products development and investment by preparation for carbon market. It is expected that the global competitiveness of domestic financial companies shall be improved by taking actions on carbon market instead of previous passive response to climate change and that Korea, the number two Carbon Emissions supplier and number one derivatives market in terms of volume, shall be able to lead the worldwide carbon market.

• Journal of Life Science
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• v.29 no.5
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• pp.621-630
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• 2019

Fertilization is the beginning of a new life that occurs in the female uterine. The female reproductive tract is composed ovary, oviduct, uterine, vagina and cervix, their physiological features are regulated by estrous cycle. Of these, uterine is a main point to establish embryo development and implantation, and intercommunication between embryo and uterine environment is necessary for suitable pregnancy. Endometrium is part of the uterine, its morphology is repetitively changed by hormones, and characteristic of uterine fluid from endometrium is also changed. Recently, massive proteins of endometrium and uterine fluid can be detected according to develop proteomics and bioinformatics and have been accelerated the understanding of the reproductive biology fields. Moreover, the massive protein information is actively studying with deeply studied theory such as sex hormone signal pathway and angiogenesis in mammals. In this paper, we review understanding of endometrium remodeling, uterine gland and fluid during estrous cycle, additionally studies on endometrium and uterine fluid based on proteomics techniques. Lastly, we introduced methods of the protein-protein correlation using bioinformatics tool that interaction with hormone receptors, representative angiogenetic factors and detected proteins using proteomics in endometrium and uterine fluid. This review will be useful to understanding the study on search of new cell mechanism in endometrium and uterine fluid.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.7
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• pp.291-298
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• 2019

We describe the improvement of insulation performance and the prevention of electrolyte leakage in a single cell in order to prevent the fuming phenomenon caused by leakage of electrolyte in a lithium secondary battery in a submerged weapon (torpedo) operated in Korea. A torpedo using lithium secondary battery as a main power source (propulsion battery) can induce the heat and fuming phenomenon, which makes it inconvenient for naval equipment operation in Korea. In the simulation test, the electrolyte of some battery cells leaked in the battery pack unit, leading to a short circuit between the main power circuit and the terminal tab of the high voltage part. We analyzed the characteristics and mechanism of the lithium secondary battery during this heat generation and fuming phenomenon. In order to prevent leakage of the electrolyte in the lithium secondary battery, the design was improved via fundamental (terminal tap enhancement) and complementary (insulation block selection and installation) measures. Comparison of the performance test before and after the improvement showed that the tensile strength of the tap terminal was improved about 2 times and the withstand voltage characteristic was improved. The application of quality improvement measures resulted in no fuming even after more than 3 years of field operation. This result is expected to improve the operation and storage stability of the torpedo propulsion cell.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.13 no.6
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• pp.129-140
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• 2003

Recently viruses and various hacking tools that threat hosts on a network becomes more intelligent and cleverer, and so the various security mechanisms against them have ken developed during last decades. To detect these network attacks, many NIPSs(Network-based Intrusion Prevention Systems) that are more functional than traditional NIDSs are developed by several companies and organizations. But, many previous NIPSS are hewn to have some weakness in protecting important hosts from network attacks because of its incorrectness and post-management aspects. The aspect of incorrectness means that many NIPSs incorrectly discriminate between normal and attack network traffic in real time. The aspect of post-management means that they generally respond to attacks after the intrusions are already performed to a large extent. Therefore, to detect network attacks in realtime and to increase the capability of analyzing packets, faster and more active responding capabilities are required for NIPS frameworks. In this paper, we propose a framework for real-time intrusion prevention. This framework consists of packet filtering component that works on netfilter in Linux kernel and traffic control component that have a capability of step-by-step control over abnormal network traffic with the CBQ mechanism.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.19 no.3
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• pp.83-93
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• 2009

In recent years, cyber crimes were intended to get financial benefits through malicious attempts such as DDoS attacks, stealing financial information and spamming. Botnets, a network composed of large pool of infected hosts, lead such malicious attacks. The botnets have adopted several evasion techniques and variations. Therefore, it is difficult to detect and eliminate them. Current botnet solutions use a signature based detection mechanism. Furthermore, the solutions cannot cover broad areas enough to detect world-wide botnets. In this study, we suggest an architecture to detect and regulate botnets using cooperative design which includes modules of gathering network traffics and sharing botnet information between ISPs or nations. Proposed architecture is effective to reveal evasive and world-wide botnets, because it does not depend on specific systems or hardwares, and has broadband cooperative framework.

• Journal of the Korean Geotechnical Society
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• v.38 no.4
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• pp.21-32
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• 2022

Steel pile foundations are widely used for offshore constructions due to their high bearing capacity and efficiency. Typically, offshore structures that have reached the end of their design life are required to be demolished. However, pile foundations are often left on site due to technical and economic limitations. The pile left on the site not only pollutes the environment, but can also cause obstacles for the construction of new structures. Therefore, research is required to completely eliminate these foundations at the site. In this study, a new type of double-wall pile foundation that can drastically reduce the pull-out load was conceptually proposed, and a series of model tests were performed to validate the performance of the double-wall pile foundation. The installation and extraction of the double-wall pile were simulated in dry sand in the model test, and the measured up-lift load was compared to that of the conventional pile. According to the result, the maximum up-lift load induced by the decommissioning of the double-wall pile was reduced by 45% when compared to the traditional pile in dense sand. This study verified the mechanism for reducing the up-lift load of the double-wall foundation and confirmed the possibility of completely decommissioning a pile that has reached the end of its nominal service life.

• Journal of Appropriate Technology
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• v.6 no.2
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• pp.94-102
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• 2020

Renewable energy (RE) is essential to comprise sustainable societies, especially, in rural villages of developing countries. Furthermore, application of off-grid RE systems to health care can improve the quality of life. In this research, a RE-based vaccination supply management system was constructed to enlarge the cold-chain in developing countries for the safe storage and delivery of vaccines. The system was comprised of the construction of RE plants and development of vaccine carriers. RE plants were constructed and connected to health posts in local villages. The cooling mechanism of vaccine carriers was improved and monitoring devices were installed. The effect of the system on vaccine cold-chain was evaluated from the field test and topographical analysis in the southern village of Nepal. RE plants were normally operated for the vaccine refrigerator in the health post. The modified vaccine carriers had a longer operation time and better temperature control via monitoring and RE-based recharging functionality. The topographical analysis estimated that the system can cover larger region. The system prototype showed great potential regarding the possibility of a sustainable and enlarged cold-chain. Thus, RE-based vaccine supply management is expected to facilitate vaccine availability while minimizing waste in the supply chain.

• Journal of Korea Trade
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• v.24 no.6
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• pp.101-114
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• 2020

Purpose - This paper examines the "Arrangement Concerning Mutual Assistance in Court-ordered Interim Measures in Aid of Arbitral Proceedings by the Courts of the Mainland and of the Hong Kong Special Administrative Region" (the Arrangement), which became effective on October 1, 2019, calling on courts of mainland China and Hong Kong for reciprocal commitment in support of court-ordered interim measures in aid of arbitral proceedings. Because the Hong Kong courts have granted interim measures in aid of arbitral proceedings seated in and outside of Hong Kong even prior to the Arrangement becoming effective, this paper focuses on the significance of the Arrangement making Hong Kong the first and only seat outside of mainland China from which parties to arbitral proceedings may successfully obtain interim measures to preserve of assets, properties, and/or evidence from Chinese courts to be enforced in China. Design/methodology - The significance of interim measures in international arbitration and the existing circumstances of interim measures in support of international arbitral proceedings in mainland China and Hong Kong are discussed first in this paper. Due to the confidential nature of arbitral proceedings, while the details of applications for interim measures pursuant to the Arrangement cannot be discussed, in examining the implications of the Arrangement, the relevant and necessary information was made available from the Hong Kong International Arbitration Centre, as it is one of the six qualified arbitral institutions under the Arrangement. Findings - This groundbreaking Arrangement provides a mechanism for parties with China-related matters to more effectively resolve their disputes, the opportunity for Hong Kong to become an unparalleled seat of arbitration, and for mainland China to overcome some of its negative perceptions in international arbitration. Because the Arrangement also allows parties to directly apply for interim measures from mainland Chinese courts, parties with China-related matters should take note of this potential bypassing of the procedural hurdle, which usually requires an arbitral institution to submit such applications in China, and make strategic decisions accordingly as may be appropriate. Originality/value - Because the Arrangement is a recent yet a significant agreement calling on courts of mainland China and Hong Kong for reciprocal commitment in support of court-ordered interim measures in aid of arbitral proceedings, this study will provide useful guidance for parties with China-related matters all over the world, especially in light of China's rapid economic growth and extensive and prominent trade relationships in today's world. Parties who foresee the need for interim measures from mainland Chinese courts should designate Hong Kong as their seat of arbitration and select one of the six qualified arbitral institutions under the Arrangement to administer their arbitral proceedings in order to benefit from the Arrangement.