• Proceedings of the Safety Management and Science Conference
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• 2012.04a
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• pp.197-204
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• 2012

• Journal of Korean Society of Transportation
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• v.22 no.4 s.75
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• pp.31-42
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• 2004

This study develops Accident Modification Factors (AMF) of countermeasures with Baysian method which are newly proposed for reducing Roadway-Rail grade crossing accidents. This study proposes a new "Bayesian Analytical Framework" for countermeasure assessment which combines "Subjective" Prior Information with "Logical" based Information. The newly proposed "Bayesian Analytical Framework" consists of the following three steps: The 1st step - Countermeasure Selection, Choice of Participants, Selection of Crashes; The 2nd step-Development of Crash History Manual and Countermeasure Evaluation Manual; The 3rd step-Development of AMFs through sound statistical tests. This study used the Komogorov-Smirnov(K-S) Test to determine whether two unknown distribution functions associated with the two populations are identical. The results of the study are that individual responses did not meet the K-S test of identical distributions. while individual vs. group distributions are identical. This indicates that combining the input of several people reduces the impact of individual subjectivity and assumptions and is important for developing a repeatable distribution to develop sound AMFs of countermeasures for reducing Roadway-Rail grade crossing accidents. The procedures of the AMF development conducted in this study can be used to estimate the safety effects of countermeasures for road segments and intersections, in addition to Roadway-Rail grade crossings.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.25 no.2
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• pp.261-270
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• 2015

In information security devices, such as Smart Cards, vulnerabilities of the RSA algorithm which is used to protect the data were found in the Side Channel Analysis. The RSA is especially vulnerable to Power Analysis which uses power consumption when the algorithm is working. Typically Power Analysis is divided into SPA(Simple Power Analysis) and DPA(Differential Power Analysis). On top of this, there is a CA(Collision Analysis) which is a very powerful attack. CA makes it possible to attack using a single waveform, even if the algorithm is designed to secure against SPA and DPA. So Message blinding, which applies the window method, was considered as a countermeasure. But, this method does not provide sufficient safety when the window size is small. Therefore, in this paper, we propose a new countermeasure that provides higher safety against CA. Our countermeasure is a combination of message and exponent blinding which is applied to the window method. In addition, through experiments, we have shown that our countermeasure provides approximately 124% higher attack complexity when the window size is small. Thus it can provide higher safety against CA.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.10
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• pp.147-158
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• 2021

Due to COVID-19, the risk of price volatility in commodity and equity markets increases. The research and application of hedging is the most effective way to reduce the market risk. Hedging is a risk management strategy employed to offset losses in investments by taking an opposite position in a related asset. We use K-means and hierarchical clustering methods to cluster companies and futures products respectively, and analyze the relationship between the number of hedging firms, regional distribution, nature of firms, capital distribution, company size, profitability, number of local Futures Commission Merchants (FCMs), regional location, and listing time. The study shows that listed companies with large scale and good profitability invest more money in hedging, while state-owned enterprises' participation in hedging is more likely to be affected by the company size and the number of local futures commission merchants, and private enterprises are more likely to be affected by the company profitability and the regional location. Listed companies are more willing to choose long-listed and mature futures products for hedging. We also provide policy advice based on our conclusion. So far, there is no study on the characteristics of hedging. This paper fills the gap. The results provide a basis and guidance for people's investment and risk management. Using clustering analysis in hedging study is another innovation of this paper.

• Korean Security Journal
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• no.7
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• pp.287-307
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• 2004

Mass killing and injuring by purpose, the countries that is hurrying countermeasure preparation of investigators who enforce that necessity to compare to intimidation of doing creature weapon is common concerns of the several countries including advanced nation such as the United States of America. Development and use of biological weapon have increased too recently to private citizens unlike development of military purpose in country dimension. The latest WHO is preparing proposal of standard stroke model who each department solidifies preparedness for chemical biological and electronic weapon revising report about biological weapon. But in case of korea, confrontation plan that bamboo broom about possibility of attack to the common people and attack comparing actual state in case of attained nothing but is readying remedy about biological warfare partially in military dimension was not readied. The purpose of this article is a study on threat of bio-weapons and the countermeasure.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.2
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• pp.204-210
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• 2010

The tactical effectiveness, which is the result of applying decision-making algorithms to respond a specific situation with weapons and sensors, is required to analyze according to the integrated combat situation, because each situation, which is intimately involved with each other, influences the surface ship to complete missions successfully. However, the tactical effectiveness have been analyzed in separation of each tactical situation due to the complexity of the integrated tactical situation. This paper is originated from the needs for analyzing the anti-submarine search region of the surface ship after it evades the torpedo by operation of the torpedo countermeasure tactics. It also describes simulation results of effectiveness analysis for the search patterns in the search region.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.12
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• pp.3165-3173
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• 1996

The existing modeling of infrared reticle seekers is perfored in a static sitic situation. Inthis paper, we develop the dynamic simulator of the reticle seekers and propose an efficient signal processing algorithm in multiple targets, especially flares. the developed simuator is essential to analyze the performance of the infrared reticle seekers in various conditions and study effective signal procesing techniques. Simulations show that the proposed counter-countermeasure algorithm is simple and efficient.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.879-882
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• 2003

Differential Power Analysis(DPA) is powerful attack method for smart card. Self-timed circuit has several advantages resisting to DPA. In that reason, DPA countermeasure using self-timed circuit is thought as one of good solution for DPA prevention. In this paper, we examine what self-timed features are good against DPA, and how much we can get benefit from it. Also we test several self-timed circuit implementation style in order to compare DPA resistance factor. Simulation results show that self-timed circuit is more resistant to DPA than conventional synchronous circuit, and can be used for designing cryptographic hardware for smart-card.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.984-989
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• 2000

This paper deals with an analysis and countermeasure of escalator vibration. The vibration characteristics of escalators are studied theoretically and experimentally to find the main cause of severe vibration. The main source of vibration in escalators is found to be chordal effect due to the step chain and sprocket system. It is also found that the vibration become significantly large at so called no load condition, in which the load due to passengers, during down-moving, is equal to the resistive force in the driving system. Dynamic absorbers are implemented to suppress the vibration. A theoretical analysis is made to determine the appropriate dynamic absorber. Theoretical and experimental study shows that dynamic absorber is effective to suppress the vibration in escalators.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.04a
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• pp.216-224
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• 1996

Recently, Korea Highway Corporation has attemped to improve the highway safety in accordance with minimizing user's imconveniences. Currently, the Anti Skidding Pavement(ASP) has been introduced as a safety countermeasure on the safety frailty sections. In this study, a series of field evaluations on pavement skid resistance have been conducted on the skid frailty sections to analyze the effects and problems of the Anti Skidding Pavement (ASP), and to understand the behavior of pavement skid resistance due to pavement type, section characteristics, vehicles' speed and traffec volume. Test results show the Anti Skidding Pavement (ASP) has the effects to induce vehicles' speed reduction. However, there are no effects to increase skid resistance. According to these results, it is demanded to improve the applying method of current Anti Skidding Pavement (ASP) to devise an effective safety countermeasure for pavement skid, and to increase pavement skid resistance.