• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.26 no.1
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• pp.17-26
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• 2008

The 1st order level network of Korea was adjusted simultaneously in 1987. After that, the 1 st order level network of Korea was adjusted simultaneously by National Geographic Information Institute in 2006. The levelling data were acquired by digital level with invar staff from 2001 through 2006. The 1st order level network consists of 36 level lines. Among them, 34 level lines comprise 11 level loops. Among 36 level lines, 4 level lines have fore & back error larger than the regulations for the 1st order levelling of NGII, Korea. Also, the closing error of 3 loops of level network exceed the regulation for the 1st order levelling of NGII. The standard error of fore and back leveling between bench marks(${\eta}_1$) are distributed between 0.2 $mm/{\surd}km$ and 1.7 $mm/{\surd}km$. The standard error of loop closing(${\eta}_2$) is 2.0 $mm/{\surd}km$. This result means that the 1st order level network of Korea qualifies for the high precision leveling defined by International Geodetic Association in 1948. As the result of the 1st order level network adjustment, the reference standard error($\hat{{\sigma}_0}$) of the level network was 1.8 $mm/{\surd}km$, which is twice as good as that of the 1st adjustment of level networks in 1987.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.7 no.1
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• pp.11-18
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• 1989

Observations to precise levelling nets contain different types of error because it has been caried out with various instruments and techniques, and also completed through long period. In order to establish a precise levelling nets, therefore, the weight function has to be selected adequately in the adjustment of nets. The purpose of the study is to determine a suitable weight function for the first order geodetic levelling nets in Korea and, therefore, the various numerical tests are performed with different statistical error models. The result of the study shows that the weight function, W＝1/$L^2$ is more efficient than W＝1/L in the first order levelling nets in the Korea.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.7 no.2
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• pp.1-6
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• 1989

The adjustment of levelling net is being done to the order of nets independently by using the least square method. For the small size net, it has difficulties in verification and statistical analysis of the net since the degree of freedom is low At the same time, it is also difficult to evaluate the error of lower order net correctly. The aim of this study is to analyse the properties of combined adjustment method compared with the independent adjustment method by using the data which have been measured during 1967-1987. Another aim is to analyse the influences of normal orthometric correction and changes of datum. Finally, Korean leveling net has been evaluated by applying real redundancy and variance component estimation.

• Journal of KIISE
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• v.44 no.12
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• pp.1290-1295
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• 2017

Document classification, a task of classifying the category of each document based on text, is one of the fundamental areas for natural language processing. Document classification may be used in various fields such as topic classification and sentiment classification. Neural network models for document classification can be divided into two categories: word-level models and character-level models that treat words and characters as basic units respectively. In this study, we propose a neural network model that combines character-level and word-level models to improve performance of document classification. The proposed model extracts the feature vector of each word by combining information obtained from a word embedding matrix and information encoded by a character-level neural network. Based on feature vectors of words, the model classifies documents with a hierarchical structure wherein recurrent neural networks with attention mechanisms are used for both the word and the sentence levels. Experiments on real life datasets demonstrate effectiveness of our proposed model.

• Journal of Digital Convergence
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• v.11 no.3
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• pp.243-253
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• 2013

As global competition is more intensive, SCM is becoming more and more important in order to achieve competitiveness. It is necessary for firms to understand weak points among the integrated supply chain through supply chain assessment in order to implement SCM successfully and cost-effectively. In this paper, we review previous studies of SCM performance measurements and propose a supply chain assessment framework for shipbuilding industry, which is one of the major ETO industry. Based on 3 supply chain domains which are demand, supply, and product management, we decompose the whole supply chain process into 3 level lower processes and propose capability measurement matric for shipbuilding firms. A case study has been conducted to validate the proposed framework and results are presented at the end.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.6 no.6
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• pp.395-402
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• 2016

Recently, firms confront to rapid environmental changes due to scientific development and demand change. Firms are trying to improve supply chain capability to react these environmental changes. Being in these improvement processes, it is important to collaborate with other partners in the supply chain. Firms have tried to outsource their in-house activity to other partners and have eliminated wasteful factors in their process and the supply chain is getting leaner. This study investigates the effect of waste factor degree on supply chain performance under external risks. Test results in this paper show that waste level has negative relationship with supply chain performance. The effect of waste level on the supply chain performance is influenced by external risk. As waste level increases, risk has moderating effect between waste level and supply chain performance. That means it is important to focus on utilization, productivity or integration properly for managing the external risk in order to improve the supply chain performance.

• Journal of Scientific & Technological Knowledge Infrastructure
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• s.12
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• pp.98-103
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• 2003

1988년 이래 국가기간전산망의 하나로 꾸준히 성장 발전하여 세계적으로 한국의 수준을 대표하는 국가과학기술 및 연구개발 망으로서의 역할을 수행하고 있고, 또한 이러한 역할이 세계수준이 되어야할 책임을 가진 초고속연구망을 상세히 들여다보고 이의 발전방향에 대해서 서술하는 것은 나의 능력으로 매우 부족할 것 같다. 하지만 이러한 매우 중요한 국가 과학기술의 젓줄인 초고속연구망을 2002년 KISTI 기관경영진단위원으로 국가 전체차원에서 다각도로 분석해본 경험과 더불어, 초고속연구망추진위원회 위원장으로서 그동안 초고속연구망(KREONET)사용자와의 교류를 통해 얻은 교훈을 접목하여 발전방향에 대한 몇가지 제언을 정리해보는 것은 나름대로 의미가 있다고 생각하여 본고를 작성하게 되었다.

• Journal of Environmental Policy
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• v.8 no.1
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• pp.31-48
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• 2009

To install and operate the Automatic Noise Monitoring Networks reasonably, which able to monitoring environmental noise continually, is an important issue for making decision to urban environment. Noise level is determined by regional environmental factors, that affected by complex urban environment. Therefore, accurate measurement of environmental noise level has top priority to establish and promote appropriate environmental policies. Currently, Automatic Noise Monitoring System is installed for grasping the environmental noise level and preparing basic data for constructing noise-reduction policies. However, this measurement data is recognized not to be able to reflect a sensory noise. The main reason is the lack of reliable measurement data and unreasonable installation site. The main point of this research ought to be the analysis of installed site of noise monitoring system in Busan.

• The Journal of the Korea Contents Association
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• v.13 no.8
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• pp.360-370
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• 2013

As the mobile telecommunications service market grows rapidly, interconnection opportunities from the fixed network to the mobile network increase and the land-to-mobile (LM) interconnection charge becomes critical factor in competition between fixed and mobile telecommunications service providers. This paper aims to evaluate the LM interconnection charge level in Korea in comparison with those of 36 foreign countries and suggest the regression model for the LM interconnection charge. Based on the regression analysis, we found that regulation, GDP per capita, wire telephone penetration, liberalization are identified as significantly affecting factors on the LM interconnection charge level, and the level of the LM interconnection charge is comparatively low.

• 전기의세계
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• v.58 no.8
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• pp.51-60
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• 2009

지능형 전력망은 통신 기술을 통해 에너지 사용을 최적화 하고 안정성을 높이는 차세대 전력망으로서 그 내부에는 다양한 통신 환경과 특성이 존재한다. 지능형 전력망에서는 일반 수용가의 부하특성이나 전기 사용량 등 비실시간 정보뿐만 아니라 전력망의 안정적이고 지능적인 운영을 위한 다양한 감시제어 데이터와 같은 실시간 정보가 함께 전달된다. 이러한 정보들은 전달 과정에서 누출, 번조가 되지 않고 원하는 사용자에게 원히는 시간과 장소에 정상적으로 전달될 수 있도록 높은 수준의 정보 보안이 뒷받침 되어야 한다. 그러나 최근, 감시제어 정보 전달은 보통 인터넷과 같은 일반적인 통신보다 고품질을 요구하기 때문에, 통신 품질을 저하시킬 수 있는 보안 서비스를 지능형 전력망에 적용하기에는 제약이 따른다. 본 논문은 지능형 전력망의 주요 통신 환경별 요구사항을 살펴보고, 이러한 요구사항을 만족시키면서 높은 수준의 정보 보안을 제공하기 위해 어떠한 보안서비스가 제공되어야 하는지 알아본다.