• Journal of Korean Society of Transportation
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• v.26 no.3
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• pp.169-178
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• 2008

Level of Service (LOS) is one of ways to evaluate operational conditions. It is very important factor in evaluation especially for the facility of highways. However, some studies proved that ${\upsilon}/c$ ratio and accident rate is appeared like a second function which has a U-form. It means there is a gap between LOS and safety of highway facilities. Therefore, this study presents a method for evaluation of a signalized intersection which is considered both smooth traffic operation (delay) and traffic safety (accident). Firstly, as a result of our research, accident rates and EPDO are decreased when it has a big delay. In that reason, it is necessary to make a new Level of Service included traffic safety. Secondly, this study has developed a negative binominal regression model which is based on the relation between accident patterns and stream. Thirdly, standards of LOS are presented which is originated from calculation between annual delay costs and annual accident cost at each intersection. Lastly, worksheet form is presented as an expression to an estimation step of a signalized intersection with traffic accident prediction model and new LOS.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.1
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• pp.73-83
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• 2019

As the awareness of the importance of Start-up increases, the number of entrepreneurs who decide to start their career is gradually increasing. However, the rate of start-up failure is still high and the qualitative level is very low due to lack of start-up performance. In this study, we analyzed the effect of entrepreneurship capability and start-up support system on start-up performance. To that end, 361 valid data were collected from businesses that were established less than seven years ago in Jeollabuk-do on August 1, 2018 and used for study verification through SPSS 21 and AMOS 21. First, the entrepreneurial competence (entrepreneurial competence, managerial competency) has a positive effect on the start-up support system and the technical competency has no significant effect. Second, entrepreneurial competence (entrepreneurial competence, managerial competency, technical competency) has a significant effect on entrepreneurial performance. However, entrepreneurial competence has a meaningful effect on the start-up performance of entrepreneurs with a negative (-) effect. Third, it was found that the start - up support system had a positive effect on the start - up performance. Finally, the start - up support system proved to have mediating effect between entrepreneurial competence and start - up performance. The implications of this study are as follows. In order to increase the start-up performance of the start-up companies, it is proved that increasing the capacity of the start-ups is an important factor. In addition, empirical studies have proved that the use of start-up support system is an important factor that directly or indirectly has a significant effect on start-up performance, We have made meaningful implications that actively supporting and utilizing entrepreneurship is necessary to enhance start-up performance.

• Journal of Internet Computing and Services
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• v.8 no.5
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• pp.81-89
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• 2007

In this thesis, we propose ontology based context-aware recommendation system using concept hierarchy(OCARCH), Context-aware recommendation services are useful to provide an user with relevant information and/or services bared on his current context, However several approaches to context-aware recommendation system have been already proposed, each of them provide information without considering level of information concept bared on his current context, For this reason, we propose OCARCH as system capable of helping people to find their way quickly and easily through large amounts of information by determining level of information concept based on his current context, We are also using prefetching algorithm to store recommendation information that the user is likely to need in the near future based on current predictions, Therefore the OCARCH enables users to obtain relevant information efficiently, Several experiments are performed and the experimental results show that the proposed system provides more effective than conventional context-aware recommendation system.

• The Journal of the Korea Contents Association
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• v.21 no.6
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• pp.678-686
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• 2021

A smiling face usually has a positive effect on interpersonal relationships by delivering a warm impression. However, the stereotype content model and compensation effect between warmth and competence suggested that warmth perceptions caused by a smiling face could influence competence perceptions negatively. This study examined the negative impact of the advertising endorser's smile on purchase intention in an expensive product category by adopting the self-construal level. The study results showed that consumers with independent-self construal (vs. interdependent self-construal) showed a lower purchase intention when exposed to an ad containing an endorser's smile. In comparison, consumers with interdependent-self construal (vs. independent self-construal) showed a lower purchase intention when exposed to an ad without an endorser's smile. Thus, this study demonstrated a moderating role of self-construal in the relationship between advertising endorser's smile and purchase intention. These findings provide valuable theoretical and practical implications for effective advertising strategies in the expensive product category.

• Korea Trade Review
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• v.43 no.2
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• pp.181-204
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• 2018

This study examines the existence of a target leverage and determinants of book and market leverage. A data set of shipping firms from 2009 to 2016 was used to conduct an empirical study. The target leverage which cannot be observed in the market is estimated using a partial-adjustment model of firm capital structure. This study found that factors affecting the capital structure differ with respect to firm size, book value leverage and market value leverage. Shipping firms have a target leverage, adjust the actual leverage toward that target leverage, and consider the target leverage as an optimum leverage. The deviation of the leverage from the target leverage plays an important role to explain changes of leverage level. The greater the deviation results in greater adjustment of shipping firms toward targets. A high level of initial debt reduces leverage changes.

• Journal of the Earthquake Engineering Society of Korea
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• v.7 no.6
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• pp.17-24
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• 2003

The main objective of this paper is to evaluate the control performance of a coulomb friction damper(CFD) for controlling the inelastic behavior of seismically excited structures, The seismic performances of various buildings are evaluated using capacity spectrum method(CSM), and the additional dampings are calculated If the evaluated performance levels of the buildings are below the target level. Maximum friction force of the CFD to achieve additional damping is provided using the concept of equivalent viscous damping, Numerical simulations for single degree of freedom(SDOF) systems with various structural periods and post yield stiffness ratios demonstrate the effectiveness of the proposed procedure.

• The KIPS Transactions:PartD
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• v.12D no.7 s.103
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• pp.937-946
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• 2005

In the current marketplace, there are maturity models, standards, methodologies and guidelines that can help an organization improve the way it does business. All SPI models including ISO/IEC I5504 and CMMI provide the capability level of software process. However, most available improvement models focus on a specific goals and Practices of the processes So my assessors need an objective process measure how to estimate achievement of goals and practices. We proposed quantitative process capability metric (PCM) which can determine the degree of capability And the effective measuring approach help SPI assessor as well as organization unit.

• Journal of KIISE:Computer Systems and Theory
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• v.32 no.9
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• pp.433-444
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• 2005

In video-on-demand(VOD) systems, a broadcast-based scheduling mechanism is known to be a very efficient technique for disseminating popular videos to very large client populations. The main motivations of broadcasting scheduling mechanisms are that they scale up extremely well and they have very modest bandwidth requirements. This paper proposes a new dynamic broadcasting scheduling mechanism, named FDBS (fast dynamic broadcasting scheme), and proves its correctness. This paper also evaluates the performance of FDBS on the basis of a simulation approach. The simulation results indicate that FDBS shows a superior performance over UD, CBHD, and NPB in terms of the average response time with very reasonable bandwidth requirements.

• Proceedings of the Korea Information Processing Society Conference
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• 2015.10a
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• pp.471-474
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• 2015

최근 사물인터넷이 빠른 속도로 발전할 것으로 예측됨에 따라서, 서비스들은 사용자들에게 제공되기 위해서 작은 디바이스부터 거대한 디바이스들간의 임베디드 디바이스의 발전과 센서 허브와 같은 보조 프로세서의 발전을 통해, 서로 연결되고 있으며, 사용자들을 위해 지금보다 더 정확하고 신뢰할 수 있는 맞춤형 사물인터넷 서비스를 제공하기 위한 개발의 필요성이 대두되고 있다. 효과적인 서비스 구축을 위한 기법들로 하위 디바이스 계층의 수준과 상위 어플리케이션 계층의 수준을 서로 구분 지을 수 있도록 서비스 지향형 컴퓨팅 방식을 사용하는 여러 계층 구성의 계층적 추상화 접근 방법이 소개되고 있지만, 사용자들에게 더 정확하고 신뢰할 수 있는 서비스를 구축하는 것은 여전히 다양한 이슈가 존재한다. 본 논문에서는 서비스 객체의 단방향 그래프 구성 기법을 적용하여, 효과적이고 신뢰할 수 있는 사물인터넷 서비스 구성을 위하여 서비스 오브젝트를 단방향 그래프 자료구조로 구성한 새로운 형태의 IoT 미들웨어 구조를 제안한다. 또한, 새로 제안된 미들웨어 구조상에서의 사용자의 사용 시나리오 및 시스템 성능상의 이점을 분산 시뮬레이션을 통하여 증명한다.

• Journal of KIISE:Databases
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• v.28 no.3
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• pp.468-483
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• 2001

In order to enhance the performance, cursor stability, which is a variant of isolation lvel 2 in relational DBMSs, has been widely used in place of isolation level 3, which uses strict two phase locking. However, cursor stability is much less usable in object-relational DBMSs (ORDBMSs) because navigational applications in ORDBMSs can suffer from critical inconsistency problems such as dangling pointers, lost updates, and reading inconsistent complex objects. In this paper, we propose a new isolation level, navigation stability, that prevents the inconsistency problems of cursor stability for navigational applications, while avoiding significant degradation of the concurrency of level 3. First, we analyze the inconsistency problems of cursor stability for navigational applications. Second, we define navigation stability as an extension of cursor stability and show that it solves those inconsistency problems of cursor stability in ORDBMSs. For workloads consisting of transactions of long duration, compared with level 3, the throughput of navigation stability is enhanced by up to 200%; the average response time reduced by as much as 55%; and the abort ratio reduced by as much as 77%. From these results, we conclude that navigation stability is a useful isolation level in ORDBMSs that can be used in place of isolation level 3 to improve the performance and concurrency without significantly sacrificing consistency.