• Journal of the Korea Institute of Information Security & Cryptology
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• v.10 no.1
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• pp.65-75
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• 2000

역할 기반 접근 제어(RBAC: Role Based Access Control)는 각 시스템 자원의 안전성을 보장하기 위한 접근 제어 기술이다. 거대한 네트워크에서 보안 관리의 복잡성과 비용을 줄여주는 기능 때문에, 특히 상업적인 분야에서 더욱 큰 관심을 끌고 있다. 본 논문에서는 RBAC 역할 계층 구조 개념만을 사용할 경우의 취약점을 해결하기 위해 두 가지 연산을 제시하였다. 그리고 이를 통하여 사용자와 권한(pemission)을 간접적으로 연관시킴으로써, RBAC 관리자가 사용자마다 연산을 추가하거나 삭제할 수 있도록 하였고 직관적인 관리자 인터페이스를 제공하여 관리자가 쉽게 사용자 역할, 그리고 연산 사이의 관계를 파악할 수 있도록 하였다. 그리고 이를 기반으로 RBAC 시스템을 설계하고 대학의 종합정보 시스템을 모델로 구현하였다.

• Journal of Radiation Protection and Research
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• v.33 no.4
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• pp.127-134
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• 2008

Potential economic impact of a hypothetical severe accident at a nuclear power plant(Uljin units 3/4) was estimated by applying the Delphi method, which is based on the expert judgements and opinions, in the process of quantifying uncertain factors. For the purpose of this study, it is assumed that the radioactive plume directs the inland direction. Since the economic risk can be divided into direct costs and indirect effects and more uncertainties are involved in the latter, the direct costs were estimated first and the indirect effects were then estimated by applying a weighting factor to the direct cost. The Delphi method however subjects to risk of distortion or discrimination of variables because of the human behavior pattern. A mathematical approach based on the Bayesian inferences was employed for data processing to improve the Delphi results. For this task, a model for data processing was developed. One-dimensional Monte Carlo Analysis was applied to get a distribution of values of the weighting factor. The mean and median values of the weighting factor for the indirect effects appeared to be 2.59 and 2.08, respectively. These values are higher than the value suggested by OECD/NEA, 1.25. Some factors such as small territory and public attitude sensitive to radiation could affect the judgement of panel. Then the parameters of the model for estimating the direct costs were classified as U- and V-types, and two-dimensional Monte Carlo analysis was applied to quantify the overall economic risk. The resulting median of the overall economic risk was about 3.9% of the gross domestic products(GDP) of Korea in 2006. When the cost of electricity loss, the highest direct cost, was not taken into account, the overall economic risk was reduced to 2.2% of GDP. This assessment can be used as a reference for justifying the radiological emergency planning and preparedness.

• Journal of Distribution Research
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• v.16 no.1
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• pp.179-222
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• 2011

This research investigates the influence of relational characteristics on 'co-defection', customer defection following salesperson turnover, in the context of salesperson-customer relationship. Based on the social exchange theory, it was hypothesized that perceived relational benefits and switching costs affect directly the customer's intentions to defect. Key constructs in relationship marketing such as customer satisfaction, trust, and loyalty were hypothesized to affect the customer's intention to defect as well as perceived relational benefits and switching costs. The results of structural equation modeling using a survey sample of 503 insurance customers who purchased life insurance policies through salespersons unveiled that the customer satisfaction with salesperson and the customer trust in salesperson strongly influence the salesperson-owned customer loyalty. However, they did not have significant direct effects on co-defection intentions. All paths from salesperson-owned customer loyalty to perceived relational benefits and perceived switching costs were also significant. Salesperson-owned customer loyalty did not have significant direct effects on co-defection intentions, but it had significant indirect effects on co-defection intentions through relational benefits and switching costs. Three sub-dimensions of perceived relational benefits had significant positive effects on co-defection intentions while the perceived switching costs had significant negative effects on co-defection intentions. The significance of our research findings were verified by comparing the hypothesized model and the rival model in the past studies.

• Journal of the Earthquake Engineering Society of Korea
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• v.12 no.3
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• pp.1-10
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• 2008

The seismic performance of a structure designed without consideration of seismic loading can be effectively enhanced through seismic rehabilitation. The appropriate level of rehabilitation should be determined based on the decision criteria that minimize the anticipated earthquake-related losses. To estimate the anticipated losses, seismic risk analysis should be performed considering the probabilistic characteristics of the hazard and the structural damage. This study presents the decision procedure in which the probabilistic seismic demand model is utilized for the effective estimation and minimization of the total seismic losses through seismic rehabilitation. The probability density function and the cumulative distribution function of the structural damage for a specified time period are established in a closed form, and are combined with the loss functions to derive the expected seismic loss. The procedure presented in this study could be effectively used for making decisions on the seismic rehabilitation of structural systems.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.132-132
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• 2018

홍수피해 발생 시 각 지역의 특성에 따라 피해의 정도가 다르게 나타나고 있다. 도시지역의 경우 포장도로로 인하여 불투수 면적이 넓어 배제 시설의 허용 용량을 초과하는 강우 발생 시 지표면 위로 유량이 누적된다. 특히 농촌지역에 비해 도시지역에서 국지적으로 기습적인 강우에 빈번히 침수피해가 발생한다. 우리나라 도시지역은 인구와 건물이 밀집되어 재산과 인명피해 및 교통체증 등으로 인한 간접피해 등 농촌지역에 비해 더 큰 피해가 발생할 수 있다. 도시 지역의 침수 피해 저감을 위해 우수 유출 저감시설과 내수배제 시설을 설치하여 우수의 유출을 지연시키거나 인위적으로 방류부 하천으로 방류시키는 방법이 있지만 이러한 시설의 설치에는 막대한 비용이 필요하며, 내수배제시설이 설치된 장소에 따라 침수현상이 다르게 나타나 저감시설 설치 전 공간적, 효율적으로 설치 가능한 장소와 침수 저감 효율에 대한 분석이 필요하다. 본 연구는 도림1 배수분구를 대상으로 XP-SWMM모델을 이용하였으며, 2010년 09월 21일 침수 발생 당시의 강우를 적용하여, 연구대상지역의 도시유출해석을 진행하였다. 또한, 어린이 공원과 학교운동장에 가상지하저류조를 설치하였을 시 침수저감 효과에 대하여 연구를 진행하였으며, 다양한 지하저류조 설치 시나리오에 따른 침수저감효과를 수심별 침수면적으로 나타내어 분석을 실시하였다. 본 연구를 통해, 도심지 지하 저류시설 도입의 기초자료로 활용될 수 있을 것으로 판단된다.

• Journal of Korea Port Economic Association
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• v.27 no.4
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• pp.13-35
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• 2011

The advancement of the information technology provides a wide range of corporate to cope with new business environments that are different in size, life and operation conditions. The Research methodology used in this study is Technology Acceptance Model. The Study Method are mainly survey and questionnaire. The major result of article can be summarized. Its are as the follows: This paper ware investigated the determinants of 'port service quality', 'perceived usefulness', 'perceived ease of use', 'utilization intention', 'practice use'. There are 400 sended samples and 150 returns, 173 of them are analyzed on a port utilization using TAM model. 1. The Port service quality are found to have a positive effect to 'perceived usefulness', 'perceived ease of use', 'utilization intention' 2. The perceived ease of use are found to have a positive effect to 'perceived usefulness', 'utilization intention' 3. The perceived usefulness is found to be positively related to 'utilization intention' 4. The utilization intention is found to have a positive effect to ''practice use' we hove to provide useful contribution to increase the Korea ports' competitiveness in introduction of port information system. In addition, in order to port development offer some insight in further research.

• Korean Journal of Construction Engineering and Management
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• v.7 no.6
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• pp.151-164
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• 2006

Numerous efforts are currently underway to automate pavementcrack and joint sealing activities. Productivity improvements, improved safety and quality, and reduced road user costs motivate these developments. Recently, an automated pavement crack sealing machine has been developed to automate the process of sealing pavement cracks and joints in Korea. This paper mainly describes the results of the economic feasibility analysis revealed through its overall performance evaluation and field tests. Finally, it is concluded that the automated machine exceeds the performance in terms of productivity, safety, and quality required in conventional method, thus making the machine economically feasible.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.37 no.3
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• pp.611-619
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• 2017

This paper intends to develop unit water production cost (UWPC) between alternative water resources including desalination, freshwater reservoirs, single-purpose dams, underground dams, and two indirect water in-take technologies - riverbank filtration and aquifer storage and recovery (ASR). The UWPCs of water supply schemes including each alternative are determined based on project cost, and operation and maintenance estimation models, which were developed based on real project cost data. The sensitivity analysis of UWPCs reveals that ASR is the lowest cost option in producing drinkable water among the alternatives, followed by riverbank filtration and underground dam. It is expected that economics related to the finding plays a critical role in supporting water resources planning and budget allocation for central and local water authority in Korea.

• Information Systems Review
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• v.7 no.2
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• pp.163-181
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• 2005

In this paper, we report case analysis on entob.com which is one of the leading domestic players in MRO e-marketplace. Critical success factors of achieving early liquidity and right ownerships are addressed for successful e-marketplace launching. Change management issues, required to encourage suppliers participation and to overcome adoption barriers from buyer firms, are suggested and illustrated for the successful implementation of the MRO e-marketplace. The business model architectures enabling to create e-intermediary value to both the suppliers and buyers are detailed. Finally, benefits of buyer firms captured through e-procurement business process streamlining and material cost savings are reported as the successful application stories. The findings suggest practical managerial insights for MRO e-marketplace implementation and further research.

• Journal of the Korean Institute of Gas
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• v.2 no.3
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• pp.49-53
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• 1998

It takes quite a long time for an analyzer, such as gas chromatography, to measure a bulk property of a system, which prevents on-line measurements. Also, the cost of installation and maintenance is very high. Consequently, some other means is needed for on-line measurements of properties and the development of soft sensors based on process variables like temperature and pressure is of great interest. In the field of gas industry, the development of a soft sensor which makes indirect on-line measurements of gas compositions and flow rate, is in progress. In this paper, we proposed a hybrid inner model PLS which improved the prediction performance by taking into account the data structure, as an empirical modeling algorithm. When applied to a design of a soft sensor of a distillation tower, the hybrid inner model PLS showed better prediction performance than other methods.