• Transactions of Materials Processing
• /
• v.20 no.3
• /
• pp.222-228
• /
• 2011

This paper is a review of biaxial tensile test equipments and specimens. The stresses acting on a component in service are multiaxial in nature. Therefore, it is necessary to consider the mechanical properties of sheet materials not only under uniaxial but also under these multiaxial stress states. Biaxial testing of metal in industry becomes an important investigation tool for the evaluation of mechanical properties of sheet metals. In this paper, several types of biaxial tensile tests were reviewed, and their advantages and limitations were discussed.

• International Commerce and Information Review
• /
• v.12 no.1
• /
• pp.327-352
• /
• 2010

3PL is the alternative for the corporation seeking to increase its logistics efficiency and effective implement of organization development. This study is to establish effective management method of the logistics companies and suggest further research direction by looking through theoretical background, applications, organization knowledge, international and domestic condition and problems of the 3PL which concludes to policy making. This study suggests corporation’s policy on technology oriented, management participation and knowledge on organization is used to secure competitive edge on logistics service. Close cooperation between departments is needed to acquire technology oriented information from 3PL human resource pool.

• Korean System Dynamics Review
• /
• v.11 no.2
• /
• pp.119-138
• /
• 2010

This study introduces the system dynamics model that simulate total operational availability when 10 equipments made of 3 major components are serviced under the constrains of the maintenance capacity level and the number of spare parts. This simulation is designed on the base of reliability engineering concept so failures of components happens with the rule of engineering factors like the mean time between failure(MTBF) of component and the next failure time of one component is effected by the conditions of other components. We analysed availability of 10 equipments under 121 constrains and executed multiple regression analysis with the simulation result. The analysis provide the managerial insight in the service fields with operation many equipments.

• Korean Management Science Review
• /
• v.15 no.2
• /
• pp.211-227
• /
• 1998

The process of implementing risk management systems for the organizations in financial service industry can be viewed as a diffusion of innovation since the introduction of the risk management systems changes the decision making process on risks faced by the organizations. The purpose of the reported research is to examine the factors that affect the successful implementation of ALM(asset & liability management) systems, the risk management systems managing interest rate risk. Specifically, this paper presents an investigation of three factors from the diffusion of innovation studies; internal factors, external factors, and time. A field survey was conducted for Korean banks that have implemented ALM systems. The results suggest that the perceived uncertainty of market, system supports, and management supports be most significantly related to the successful implementation of the risk management systems. The findings of the current study also suggest a certain amount of time should be passed to diffuse the risk management systems in organizations.

• Korean Management Science Review
• /
• v.11 no.2
• /
• pp.147-159
• /
• 1994

The problems of determining appropriate QOS(Quality of service) requirements of B-ISDN services and finding the corresponding NP(Network Performance) values satisfying the given QOS requirements are very important problems which are directly related to the successful operation of the ATM network, but have not been studied with enough attention yet. The QOS(NP) parameter definition, QOS measurements, and QOS managements are three major problems that should be solved. In this paper, we first introduce the basic concepts of QOS and NP and their relationships. Then we discuss more comprehensive concepts of QOS based on the layered structure of ATM services and the reference time, which can provide a systematic approach for QOS and NP mapping problems. We also provide examples of determining basic QOS(NP) parameters in the ATM layer and a specific example of QOS mapping based on the file transfer in ATM. The results of this paper can be used to establish the comprehensive QOS management model.

• Korean Management Science Review
• /
• v.11 no.3
• /
• pp.103-128
• /
• 1994

Due to the trend of evolution toward a broadband communication network with fiber-optics, the design and operation of fiber-optic network have been received a great deal of research attention recently. Furthermore, even a single fiber link failure in the network may result in severe service loss. Thus, the network survivability becomes an importantissue in planning and designing the network. This survey is on modelling of various fiber-optic subscriber loop network(FSLN) design problems, which are essential ones for providing broadband communication services and B-ISDN services. Models are classified and investigated as either conventional decomposition-iteration approach or integrated design method. To build survivable networks, SHR models are also suggested by ring control schemes. The result of this study will be effectively applied to build a design model for FSLN in the practical applications.

• East Asian Economic Review
• /
• v.17 no.1
• /
• pp.27-53
• /
• 2013

In this paper, we look at the relationship between international trade and the rule of law, using the World Justice Project Rule of Law Index, which include index figures on human rights, limits on government powers, transparency and regulatory efficiency. Based on regression analyses using the rule of law index figures and international trade figures (merchandise trade, service trade, exports and imports as percentage of GDP,) international trade and basic human rights seem to have little relationship; but trade has a close positive relationship with strong order and security. Somewhat surprisingly, regulatory transparency and effective implementation seems to have little or no effect on international trade and vice versa. International trade shows a clear positive relationship with the country's criminal justice system, but the relationship with the civil justice system is not as clear as such. For regulatory implementation and civil justice, services trade positively affect these institutions, but these institutions in turn affect exports more strongly than services trade. Finally, the effect of trade on rule of law is stronger on a medium to long term (10-20 year) time horizon.

• East Asian Economic Review
• /
• v.21 no.2
• /
• pp.147-165
• /
• 2017

This study quantifies the dynamic interrelationship between the KOSPI index return and search query data derived from the Naver DataLab. The empirical estimation using a bivariate GARCH model reveals that negative contemporaneous correlations between the stock return and the search frequency prevail during the sample period. Meanwhile, the search frequency has a negative association with the one-week- ahead stock return but not vice versa. In addition to identifying dynamic correlations, the paper also aims to serve as a test bed in which the existence of profitable trading strategies based on big data is explored. Specifically, the strategy interpreting the heightened investor attention as a negative signal for future returns appears to have been superior to the benchmark strategy in terms of the expected utility over wealth. This paper also demonstrates that the big data-based option trading strategy might be able to beat the market under certain conditions. These results highlight the possibility of big data as a potential source-which has been left largely untapped-for establishing profitable trading strategies as well as developing insights on stock market dynamics.

• Review of KIISC
• /
• v.14 no.1
• /
• pp.35-45
• /
• 2004

미래 유비쿼터스 컴퓨팅 환경의 네트워크 인프라 구축을 위한 핵심기술은 무선 ad hoc 네트워크이다. 이러한 ad hoc 네트워크에 대한 보안은 일반 네트워크와 마찬가지로 보안성, 무결성, 가용성 등이 요구되지만. 일반적으로 무선네트워크라는 점, 고정 인프라가 없다는 점, 네트워크 토폴로지가 수시로 변한다는 점 등 때문에 보안문제는 훨씬 어려운 것으로 인식되고 있다. 본 논문에서는 보안 요구사항 중에서 가용성에 중점을 두어, 일반 네트워크와는 다른 유비쿼터스 네트워크에서의 DoS 공격의 여러 가지 유형을 분석한다. 또한 이러한 DoS 공격이 유비쿼터스 네트워크에 미치는 영향을 컴퓨터 시뮬레이션을 통해 전송성능과 생존성의 측면에서 분석한다. 본 논문의 실험결과는 같은 유형의 DoS 공격이더라도 무선 ad hoc 네트워크가 일반적인 네트워크에 비해 더 심각한 피해를 당할 수 있음을 보여준다.

• Review of KIISC
• /
• v.21 no.5
• /
• pp.65-70
• /
• 2011

스마트폰 시장이 전체 모바일 시장에서 큰 비중을 차지하고 있으며, 사용자 수는 급격하게 증가하고 있다. 스마트폰은 다양한 인터페이스 및 기능 등 기존 휴대폰과는 차별화된 장점을 가지고 있으며, 사용자의 취향에 따라 어플리케이션 설치 및 제거가 가능하다. 또한 신용정보, 인증서, 전화번호부 등 다양한 개인정보를 저장하고 있으며, 업무용으로도 사용되고 있다. 이러한 정보를 저장하고 있는 스마트폰에는 다양한 보안 위협이 존재하고 있으며, 개인 및 기업에게 치명적인 피해를 발생 시킬 수 도 있다. 특히 스마트폰을 이용한 DDoS 공격은 기존 DDoS(Distributed Denial of Service) 공격과 비슷하지만 스마트폰만이 가지고 있는 환경 때문에 여러 가지 다른 특정을 보인다. 본 논문에서는 기존 DDoS 공격 기법 및 동향을 알아보고, 좀비 스마트폰과 좀비 PC의 환경을 비교 분석함으로써 스마트폰 DDoS 공격 동향을 살펴본다.