• The Journal of the Korea Contents Association
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• v.18 no.3
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• pp.148-159
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• 2018

This study empirically examined the influence of ownership structure(public/private) and revenue structure (high dependency on advertisement/low dependency on advertisement) of broadcasting companies upon journalists' perceptions regarding the degree of freedom in news reporting, the factors that limit freedom of press, satisfaction with the work autunomy and satisfaction with company's policies of news reporting and editing in light of resource dependency theory. The result showed that both the ownership structure and revenue structure of broadcasting companies influenced the journalists' perception regarding the degree of freedom in news gathering and reporting. It was also confirmed that only the revenue structure affected the level of satisfaction with work autonomy while the degree of satisfaction with the company's policies on editing and programing was influenced by the ownership structure. The perception of the factors that limit the freedom of press was found to be influenced only by the ownership structure, as did the satisfaction with policies on editing and programing. These results are very significant as they show that the level of dependence on advertising revenue affects journalists' news reporting, and that journalists of public broadcasting companies are influenced by the dependence on government or other political powers as well as on advertising revenue.

• Proceedings of the Korean Magnestics Society Conference
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• 1999.04a
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• pp.80-81
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• 1999

• Annual Conference on Human and Language Technology
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• 1996.10a
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• pp.464-468
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• 1996

본 논문에서는 한국어 의존관계 파서의 정확성 및 효율성을 높이기 위해 구구조 내의 지역적 수식 특성을 반영할 수 있는 지역 의존관계의 사용을 제안한다. 의존문법은 자유어순 언어를 잘 설명할 수 있는 장점이 있지만, 전체 문장구조에 관한 의존제약이 너무 미약하기 때문에 단순히 어절간 구문 의존 제약만으로는 원하지 않는 분석 결과가 너무 많이 생성된다. 그러나 자유어순 언어라 하더라도 지역적인 구구조에는 일정한 어순 제약이 존재한다. 명사구, 용언구 등과 같은 구구조를 분석해 보면 수식어의 지배소는 반드시 그 구 안에 있다. 이러한 구조 정보에 기반을 둔 지역 의존관계 규칙을 이용하면 하나의 의존소에 대해서 지배소로 사용될 수 있는 어절의 범위를 제한하여, 원하지 않는 분석 결과를 줄일 수 있다. 한국어는 기본 문장 구조가 그대로 사용되기보다는 하나 이상의 수의 요소들이 첨가되어 보다 긴 문장 구조로 사용되는 경우가 많기 때문에, 본 논문에서 제안한 방법은 시스템 전체의 성능 및 효율을 크게 향상시킬 수 있다. 실험에서는 파싱의 첫 번째 단계에서 지역 의존관계 규칙을 사용하였을 경우 사용하지 않았을 때에 비해서 의존관계의 수가 평균 69% 정도로 줄어들었다.

• Journal of Korean Association for Spatial Structures
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• v.4 no.1 s.11
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• pp.61-68
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• 2004

The wind tracker and structural monitoring system recorded wind and dynamic response data. The measured building is located in the moutatin in Sokcho. The damping ratio and natural frequency were analysed in this paper to obtain amplitude dependence. Amplitude dependent damping was showed clearly in the increasing rate of 9%. The tendency of dynamic properties of building obtained here are useful for the validation of dynamic properties of buildings in the evaluation of serviceability.

• Korean Journal of Optics and Photonics
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• v.18 no.5
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• pp.295-302
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• 2007

This paper presents a rigorous comparison of the design characteristics of polarization-insensitive directional coupler (DC) and multimode interference (MMI) coupler based on rib type waveguides, by using longitudinal modal transmission-line theory (L-MTLT). It shows that the multimode mixing and interference property of MMI can be structurally designed through the continuous evolution of the two-mode coupling property of DC. It also compares and analyzes the coupling efficiency along with the coupling length and the wavelength between polarization-insensitive DC and MMI. From the design properties obtained, it demonstrates for the first time the integration of polarization-insensitive DC or MMI with a Bragg grating and evaluates precisely the filtering characteristics. The numerical results reveal that the DC, as long as it is designed to have the same coupling length for TE and TM modes, has better performance than the MMI in polarization-insensitive filtering behaviour. However, it shows that the MMI with much less coupling length than DC is preferred in the miniaturization of integrated devices.

• Journal of the Korean Magnetics Society
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• v.16 no.1
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• pp.60-65
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• 2006

In order to investigate the dependence of the particle size on the cation distribution in the spinel structure, Mossbauer spectra were taken in the presence of an external magnetic field f3r the magnetic nanoparticles prepared by using a microemulsion method. The crystals are found to have a cubic structure. The results show that as the particle sizes decrease, $Fe^{3+}$ ions migrate from the octahedral site to tetrahedral site.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2011.04a
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• pp.697-700
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• 2011

본 논문에서는 X-FEM을 사용하여 혼합모드 하중 상태에서의 이차원 선형탄성체의 균열문제에 대한 형상 설계민감도 해석을 수행하였다. X-FEM이란 균열과 같은 특수한 해를 근사하는 방법으로써, 확장함수를 도입하여 FEM의 한계를 극복하는 방법론이다. X-FEM 하에서 해를 근사하는 데 쓰이는 확장함수들은 불연속성과 특이성을 포함하고 있어 물리적 영역에 의존한다. 이는 설계민감도 해석을 수행하는 과정에서 그러한 의존성을 고려해주는 것이 필요하다. 따라서 본 논문에서는 X-FEM 기반의 형상 설계민감도 해석해를 제안하고자 한다. 식의 유도는 전 미분 공식에 기초하고 있으며, 형상함수의 설계변분에 대한 의존성에 관한 항을 추가시켰다. 또한, 균열 주위의 국부적인 공간에서의 확장된 자유도에 설계속도를 가한다. 이에 대한 몇 가지 수치 예제를 통하여 개발된 방법론의 타당성을 확인하였다.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.20 no.6
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• pp.761-767
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• 2007

In centralized control system, complicated control systems including sensors, power supply and dampers should be required to satisfy the target response of large-scale structures. The practical applications of the centralized control system, however, is very difficult due to high order finite element model of structures, uncertainty of models, and limitations of the excitation system. In this study, the decentralized response-dependent MR damper of which magnetic field is automatically modulated according to the displacement or velocity transferred to the damper without any sensing and computing systems. this decentralized response-dependent MR damper are investigated according to the ranges of relative magnitude between the control force of MR damper and the story shear force of structures by nonlinear time history analysis. Finally, its performance is compared with centralized LQR algorithm which is used in general centralized control theory for a three story building structure.

• Journal of Korea Port Economic Association
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• v.36 no.4
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• pp.93-106
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• 2020

Trade is an important economic activity. In particular, since the establishment of the World Trade Organization (WTO), the scope of trade has been expanding due to events such as the entry of China into the WTO in 2001, the establishment of a multilateral trading system, mitigation and integration of trade barriers, and the establishment of the free trade agreement (FTA). Despite the expansion of the trade market, however, extreme events such as the 2008 global financial crisis, the 2016 Brexit, and the 2018 US-China trade war have had a direct negative impact on the trade market. Therefore, the present this study analyzed the dependence structure between the international shipping freight rate index, a variable representing trade activities, and the trade uncertainty between the US and China. The following is a summary of the analysis results. First, the US-Chinese trade policy uncertainty and international shipping freight rate index presented a Frank copula and rotated Clayton copula 270° distribution, respectively, showing the same distribution structure for each country. Second, the Kendall's tau correlation revealed a negative dependence between the international shipping freight rate index and US-Chinese trade policy uncertainty. The degree of dependence was greater in the combination of uncertainty in China's trade policy and international shipping freight rates. In other words, the dependence of global demand and trade policy uncertainty confirmed that China was stronger than the US. Finally, the tail dependence results revealed that the US-Chinese trade policy uncertainty and international shipping freight rates were independent of each other. This means that extreme events related to the trade policy uncertainty or international shipping rate index were not affected by each other.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2009.04a
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• pp.412-415
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• 2009

본 논문에서는 등기하 해석법을 이용하여 설계 의존형 하중조건을 갖는 구조물에 대한 형상 최적설계 를 수행하였다. 유한요소 기반 형상 최적설계는 설계영역 매개화에 어려움이 있으나 등기하 해석법은 NURBS 기저 함수와 조정점을 이용함으로써 기하학적 표현이 용이하다는 장점을 가지고 있다. 기하학적으로 정확한 모델은 응답 및 설계민감도 해석에 사용되며, 설계구배 기반의 최적화에 있어서 중요한 역할을 한다. 하중조건이 설계영역의 변화에 따라 변하는 최적설계 문제에서 경계에서 설계민감도가 부정확한 경우, 설계공간에서 최적설계가 균일한 수렴성을 갖기 어렵다. 즉 유한요소법을 이용한 형상 최적설계에서 설계 의존형 하중조건을 갖는 문제를 푸는 경우, 최적설계를 진행할 때 변하는 경계의 부정확성 때문에 정확한 설계민감도를 얻기가 어려운 점이 있다. 본 논문에서는, 엄밀한 기하형상을 표현하는 등기하 설계민감도를 활용한 형상 최적설계 기법이 설계 의존형 하중조건을 갖는 문제에서 좋은 결과를 제시함을 확인하였다.