• Journal of the KSME
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• v.53 no.5
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• pp.45-50
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• 2013

인체장기칩(Human Organs-on-Chips)은 미세공학, 생체모방, 세포생물학 분야의 기술을 시너지 있게 접목하여 개발되는 신개념의 인체 대리모델이다. 이 글에서는, 이러한 생체모사 시스템의 개발 배경과 최근 연구동향, 그리고 잠재성에 대해서 살펴본다.

• Journal of Environmental Policy
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• v.6 no.4
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• pp.103-127
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• 2007

This study presents the political economics models to explore the political landscape of special interest groups influencing the government's decision making process for implementing international environmental standard. Starting with the popular menu-auction types of lobbying frameworks in the literature, the study extends its scope of research to multi-principal and multi-agency based international interest group politics and its hybrid case in order to bring the interaction of the relevant interest politics to the fore. Within a specific factor model of international trade between 2 small open economies, we compare the political equilibrium environmental standards in different institutional frameworks which can be feasible in the sense of recently growing role of environmental interest group. Although the conventional finding suggests that cooperative bargaining between the two countries can attain the globally optimal level of the standard, the paper rather explains that the cooperation between the national interest groups and the hybrid case also generate the stricter standard then national interest politics usually do.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.6B
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• pp.559-567
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• 2009

Distributed Content Delivering Network (DCDN) will make use of the existing resources of the common Internet users in terms of storage space, bandwidth and Internet connectivity to create it. However DCDN has some limitations that are inefficient using of storage space, reliability and having special load balancing (LB) algorithm. So, this paper proposes Re-distribution based CDN (RDCDN) that overcomes the limitations of DCDN. RDCDN has the content re-distribution algorithm and separates surrogates to main surrogate and sub surrogates. Main surrogate can help service reliability be improved by storing all contents as back-up system. And content re-distribution algorithm also can help storage space be saved because all contents are not stored in every surrogate. Especially, when RDCwDN uses content re-distribution algorithm, it can work active load balancing function without extra LB algorithm like as DCDN. Results of simulation show that the proposed architecture can improve reliability and efficiency of storage space, and it also can offer the same performance as that of commercial CDN and DCDN.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.7
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• pp.535-540
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• 2019

The coupling between different models for MDO (Multi-disciplinary Optimization) greatly increases the complexity of the computational framework, while at the same time increasing CPU time and memory usage. To overcome these difficulties, POD (Proper Orthogonal Decomposition) and RBF (Radial Basis Function) are used to solve the optimization problem of determining the thickness of composites and sandwich cores when composite sandwich structures are used as aircraft wing skin materials. POD and RBF are used to construct surrogate models for the wing shape and the load data. Optimization is performed using the objective function and constraint function values which are obtained from the surrogate models.

• Journal of Digital Convergence
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• v.18 no.6
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• pp.17-32
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• 2020

This study analyzes the regulatory issues of stakeholders, the firm, the government, and the individual, in the data industry using the principal-agent theory. While the importance of data driven economy is increasing rapidly, policy regulations and restrictions to use data impede the growth of data industry. We applied descriptive case analysis methodology using principal-agent theory. From our analysis, we found several meaningful results. First, key policy actors in data industry are data firms and the government among stakeholders. Second, two major concerns are that firms frequently invade personal privacy and the global companies obtain monopolistic power in data industry. This paper finally suggests policy and strategy in response to regulatory issues. The government should activate the domestic agent system for the supervision of global companies and increase data protection. Companies need to address discriminatory regulatory environments and expand legal data usage standards. Finally, individuals must embody an active behavior of consent.

• Journal of KIISE:Computing Practices and Letters
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• v.5 no.1
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• pp.122-133
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• 1999

OSI 망 관리는 TMN의 하부 구조로 채택됨에 따라서 앞으로 더욱 많이 쓰일 것으로 기대된다. OSI 망관리는 관리자-대리인 모델을 기본으로 하는데 , 관리 시스템(관리자 역할) 보다 관리대상 시스템(대리인 역할)이 더 중요한 역할을 수행하는 특징을 가진다. 기존의 관리대상 시스템들은 많은 관리 객체들을 대상으로 하는 CMIS 연산 요구를 받았을 때, 관리 객체들을 순차적으로 처리하기 때문에 빠른 응답시간을 보장할 수 없었다. 본논문에서는 CMIS 연산을 효율적으로 처리하는 관리대상 시스템을 위한 다중 쓰레드 기반의 프로세스 구조를 제안한다. 제안된 시스템은 OSIMIS TMN플랫폼을 이용해서 솔라리스 운영체계에서 구현되었다. 제안된 시스템의 성능을 측정해본결과, 관리대상 시스템 내부의 망 자원들을 관리할 때는 성능이 그리 좋지 않았으나 , 시스템 외부의 망 자원들을 관리 할 때는 뛰어난 성능을 보였다.

• Annual Conference on Human and Language Technology
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• 2020.10a
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• pp.563-568
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• 2020

본 연구에서는 블랙박스로 알려진 딥러닝 모델에 설명 근거를 제공할 수 있는 설명자 모델을 적용해 보았다. 영화평 감성 분석을 위해 MLP, CNN으로 구성된 딥러닝 모델과 결정트리의 앙상블인 Gradient Boosting 모델을 이용하여 감성 분류기를 구축하였다. 설명자 모델로는 기울기(gradient)을 기반으로 하는 IG와 레이어 사이의 가중치(weight)을 기반으로 하는 CAM, 그리고 설명가능한 대리 모델을 이용하는 LIME과 입력 속성에 대한 선형모델을 추정하는 SHAP을 사용하였다. 설명자 모델의 특성을 보기 위하여 히트맵과 관련성 높은 N개의 속성을 추출해 보았다. 설명자가 제공하는 기여도에 따라 입력 속성을 제거해 가며 분류기 성능 변화를 측정하는 정량적 평가도 수행하였다. 또한, 사람의 판단 근거와의 일치도를 살펴볼 수 있는 '설명 근거 정확도'라는 새로운 평가 방법을 제안하여 적용해 보았다.

• Journal of the Society of Disaster Information
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• v.19 no.4
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• pp.976-983
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• 2023

Purpose: The dynamic behavior of a bridge structure under seismic loading depends on many uncertainties, such as the nature of the seismic waves and the material and geometric properties. However, not all uncertainties have a significant impact on the dynamic behavior of a bridge structure. Since probabilistic seismic performance evaluation considering even low-impact uncertainties is computationally expensive, the uncertainties should be identified by considering their impact on the dynamic behavior of the bridge. Therefore, in this study, a global sensitivity analysis was performed to identify the main parameters affecting the dynamic behavior of bridges with I-curved girders. Method: Considering the uncertainty of the earthquake and the material and geometric uncertainty of the curved bridge, a finite element analysis was performed, and a surrogate model was developed based on the analysis results. The surrogate model was evaluated using performance metrics such as coefficient of determination, and finally, a global sensitivity analysis based on the surrogate model was performed. Result: The uncertainty factors that have the greatest influence on the stress response of the I-curved girder under seismic loading are the peak ground acceleration (PGA), the height of the bridge (h), and the yield stress of the steel (fy). The main effect sensitivity indices of PGA, h, and fy were found to be 0.7096, 0.0839, and 0.0352, respectively, and the total sensitivity indices were found to be 0.9459, 0.1297, and 0.0678, respectively. Conclusion: The stress response of the I-shaped curved girder is dominated by the uncertainty of the input motions and is strongly influenced by the interaction effect between each uncertainty factor. Therefore, additional sensitivity analysis of the uncertainty of the input motions, such as the number of input motions and the intensity measure(IM), and a global sensitivity analysis considering the structural uncertainty, such as the number and curvature of the curved girders, are required.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.6
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• pp.567-581
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• 2008

As the size of the web is growing explosively, search engines are becoming increasingly important as the primary means to retrieve information from the Internet. A search engine periodically downloads web pages and stores them in the database to provide readers with up-to-date search results. The web crawler is a program that downloads and stores web pages for this purpose. A large-scale search engines uses a parallel web crawler to retrieve the collection of web pages maximizing the download rate. However, the service architecture or experimental analysis of parallel web crawlers has not been fully discussed in the literature. In this paper, we propose an architecture of the parallel web crawler and discuss implementation issues in detail. The proposed parallel web crawler is based on the coordinator/agent model using multiple machines to download web pages in parallel. The coordinator/agent model consists of multiple agent machines to collect web pages and a single coordinator machine to manage them. The parallel web crawler consists of three components: a crawling module for collecting web pages, a converting module for transforming the web pages into a database-friendly format, a ranking module for rating web pages based on their relative importance. We explain each component of the parallel web crawler and implementation methods in detail. Finally, we conduct extensive experiments to analyze the effectiveness of the parallel web crawler. The experimental results clarify the merit of our architecture in that the proposed parallel web crawler is scalable to the number of web pages to crawl and the number of machines used.

• (The) Research of the performance art and culture
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• no.18
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• pp.481-512
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• 2009

This thesis is to investigate the effectiveness of Cinema Therapy through the aspect of vicarious learning, that is, Nayeoug's modelling after Yeonsun, and Yeonsun's modelling after The Little Mermaid, by making My Mother, the Mermaid directed by Park Heungsik. After immature Nayeoung returns from the travel into past time, she is reborn as an mature woman, and finally she can manage a happy marriage life. In Nayeoung's initiation, there is Yeonsun's initiation, in that again, there is a initiation of The Little Mermaid by Hans Christian Andersen. This work is a proper text in explaining the effectiveness of Cinema Therapy which aims at self-awareness and self-improvement because it contains some aspects of the vicarious learning through the movie. Nayeon's mother(Yeonsun), Nayeoung's father(Jinguk) have trouble, and sometimes have friendly relations. The major characters' wish and need are examined out through the analysis of the five basic needs based on reality therapy. As a result, it is found out that when their needs are fulfilled, friendly relation is formed, and when their needs are not fulfilled, unfriendly relation is formed. If their own basic desires are examined, their desires can be fulfilled through the inner control by themselves.