• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2012.07a
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• pp.145-149
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• 2012

2005년 국내에서 본방송을 실시한 DMB는 모바일 방송이라는 새로운 방송 이용 환경을 창출하였다. 더불어 기존 TV를 통한 재난 방송의 사각지대로 거론되어 온 야외, 정전, 해상, 이동 환경에서 재난정보를 전달할 수 있어 방송 매체로 평가되면서, 다양한 기술 개발이 진행되었다. KBS는 DMB를 통한 재난경보방송 기술을 구현하여 2008년 제주도 지역 실험방송과 2009년 전국 실험방송을 거쳐 2010년 8월부터 본방송을 실시하는 등, DMB 재난경보방송 체계 마련을 위해 노력하여 왔다. 이러한 과정에서 차기 국가 모바일 재난경보 체계 마련의 필요성과 방향성에 대한 경험적 안을 제시해 본다. 본 연구는 급변하는 미디어 환경을 고려하여 모바일 재난 정보 전달체계에서 통신망의 역할을 강화하여 방송과 융합한 모델을 마련하고, 조속히 범국가적 재난정보의 표준 규격을 마련할 것을 촉구하며, 궁극적으로 뉴미디어 도입 정책에서 재난 정보전달에 관한 공공성 정책이 우선되어야 함을 제시하였다.

• Journal of KIISE:Computing Practices and Letters
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• v.13 no.6
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• pp.422-426
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• 2007

Personal mobile devices equipped with non-volatile storage such as MP3 player, PMP, cellular phone, and USB memory require safety for the stored data on the devices. One of the safety requirements is secure deletion, which is removing stored data completely so that the data can not be restored illegally. In this paper, we study how to design the secure deletion on Flash memory, commonly used as storage media for mobile devices. We consider two possible secure deletion policy, named zero-overwrite and garbage-collection respectively, and analyze how each policy affects the performance of Flash memory file systems. Then, we propose an adaptive file deletion scheme that exploits the merits of the two possible policies. Specifically, the proposed scheme applies the zero-overwrite policy for small files, whereas it employs the garbage-collection policy for large files. Real implementation experiments show that the scheme is not only secure but also efficient.

• Korean journal of communication and information
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• v.36
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• pp.374-398
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• 2006

This paper attempts to identify motivations of the satellite DMB use and to examine the relationship between user motivations and structure of genre consumption. Firstly, this paper identified motivational dimensions for satellite DMB usage. The results of the factor analysis revealed three dimensions: information-seeking, entertainment-oriented and social communication. It accounts for 69.9% of the variances found within this data. Secondly, the results of the regression analyses suggested that both information seeking and entertainment-oriented motivations were closely related to genre preferences of satellite DMB contents. In addition, these two motivations predicted genre repertoires and similarity in genre consumption. In conclusion, motivations of the satellite DMB use were the best predictors for explaining the structure of genre consumption.

• Journal of Radiation Protection and Research
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• v.27 no.2
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• pp.111-120
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• 2002

A reference scenario of vault safety case prepared by the IAEA for the near-surface disposal facility of low-and informed]ate-level radioactive wastes is assessed with the MASCOT program. The appropriate conceptual models for the MASCOT implementation is developed. An assessment of groundwater pathway through a drinking well as a geosphere-biosphere interface is performed first. then biosphere pathway is analysed to estimate the radiological consequences of the disposed radionuclides based on compartment modeling approach. The validity of conceptual modeling for the reference scenario is investigated where possible comparing to the results generated by the other assessment. The result of this study shows that the typical conceptual model for groundwater pathway represented by the compartment model ran be satisfactorily used for safety assessment of the entire disposal system in a cons]stent way. It is also shown that safety assessment of a disposal facility considering complex and various pathways would be possible by the MASCOT program.

• Journal of Distribution Research
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• v.15 no.5
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• pp.103-126
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• 2010

The development of an industry including distribution sector is influenced by not only government policy but the related firms' behaviors. Recently the large-scale retailers have had more enormous channel power than any other distributors including monopolistic makers. Now is the time for government to prepare some policies against the unfair transaction behaviors by large-scale retailers. In this paper I tried to inquire into the distribution competition policy from a political correspondent point of view related with the transition of distribution system. For the purpose of this article I compared the case of Korea with Japan. According to the results so far inquired, there are some commons and differences in the cases of the two. Some suggestions are as follows. Considering the predominant position the concept of large-scale retailers is to be extended from a single store to numerous chain stores in the political level. Government needs to examine the standard propriety for large-scale retailer; the size of selling area and amount of sales a year. When a large-scale retailer store is to be established, it need to be taken a permit or a pre-inspection. The Fair Trade Commission have to secure the neutrality from Government's strategies. And government should find out the examples of unfair transaction behavior types and prepare some proper guidelines continually. For the last time statistical data by distributors are to be fitted out and the actual investigations for estimating the effects of government policies need to be enforced.

• Korean Chemical Engineering Research
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• v.50 no.5
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• pp.843-849
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• 2012

When we use NiO based particle as an oxygen carrier in a chemical looping combustion system, the fuel conversion and the $CO_2$ selectivity decreased with increasing reaction temperature within high temperature range (> $900^{\circ}C$) due to the increment of exhaust CO concentration from reduction reactor. To improve reduction reactivity at high temperature, the applicable metal oxide component was selected by calculation of the equilibrium CO concentration of metal oxide components. After that, feasibility of reduction reactivity improvement at high temperature was checked by using solid mixture of the selected metal oxide particle and NiO based oxygen carrier. The reactivity was measured and investigated using batch type fluidized bed. The solid mixture of $Co_3O_4/CoAl_2O_4$(10%) and OCN706-1100(90%) showed higher fuel conversion, higher $CO_2$ selectivity and lower CO concentration than OCN706-1100(100%) cases. Consequently, we could conclude that improvement of reduction reactivity at high temperature range by adding some $Co_3O_4$ based oxygen carrier was feasible.

• Journal of Soil and Groundwater Environment
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• v.6 no.1
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• pp.53-62
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• 2001

Effects of surface defect on thermal stability and stress crack resistance of high density polyethylene geomembranes in environmental conditions were examined by comparing the mechanical properties, chemical resistance and failure times of geomembranes between defective cases under different temperatures. Artificial surface defects were added to the surface of geomembranes by scratch apparatus designed specially. The number of surface defects was increased with the smaller size of scratch induced particles, and the more scratch addition numbers at the shear rate of scratch induced mechanism, 100mm/min. The tensile strength were decreased but the tensile strain was increased with the above conditions. In chemical resistance of defective geomembranes, the tensile strength were decreased but the tensile strain was increased with the longer immersion period and the higher temperature under the same scratch induced conditions. Finally, failure times of defective geomembranes by ESCR test were shifted to the shorter time ranges by increasing temperatures.

• Archives of design research
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• v.19 no.2 s.64
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• pp.217-228
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• 2006

It is obvious that the characteristics of the media are related with the visual expression found in film and video shots. It can be assumed that there would be unavoidable distortion when the space and objects are being framed into an image by the camera and that unavoidable distortion can be utilized for creative expression. Therefore the relationship among the shape of filming zone, the structure of the image, and the strategies of disposition of camera, actors, and objects were studied in accordance with expressional attempts found in film and video images. The classified cases of the expressions found in film and video was studied from the view of the dispositions and movements of the physical elements such as camera, actors, and objects which made the designated expression possible. Finally the organization of method to arrange of the elements used for film within film zone was resulted as the expressional directing methods for filming. Later the usefulness of the method was tested by the application of the method in educational procedure and the evaluation of the analysis of the students' results.

• Proceedings of the Korea Society of Design Studies Conference
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• 2005.10a
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• pp.66-67
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• 2005

기존의 데스크톱 컴퓨터가 고정된 공간에서만 사용되는데 반해 개인용 정보단말기(PDA)는 이동하면서 사용이 가능하다는 특징 때문에 소형화면과 작은 부피, 가벼운 용량의 특징을 지닌다. 그러나 이러한 제한된 화면에서는 한 번에 볼 수 있는 정보량이 적어 사용자 중심의 PDA용 GUI 아이콘 설계를 위해서는 우선 PC와 PDA간의 호환을 자유롭게 하는 인터페이스 디자인이 선행되어야 한다. 기존 소형화면에서는 한 번에 볼 수 있는 정보량이 적기 때문에 전체에 대한 개관이 불가능했고, 많은 정보를 담으면, 내용이해가 어려웠는데, 본 논문에서는 효율적인 GUI 아이콘 설계를 통해 정보의 ‘집중’과 ‘선택’ 이 가능한 PDA의 인터페이스 디자인을 알아보고자 한다. 대량 정보를 작은 화면에 종합적으로 담아내어 개관을 가능하게 하고, 정보의 내용과 가치를 아이콘의 크기와 색, 수직 혹은 수평적인 움직임 등의 시각화를 통해 차별화시킴으로써 개별 정보내용의 이해를 가능하게 한다. 앞으로 PDA와 PC의 표준화된 호환 가능한 브라우저가 모든 PDA에 기본 인터페이스로 장착된다면, 다른 매체들 간의 데이터 전송 시스템의 호환을 순조롭게 하여 경제적인 파급 효과 뿐만 아니라 차세대 이동통신의 영역까지 확장하여 산업적인 파급효과도 클 것으로 예상된다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2014.06a
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• pp.15-17
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• 2014

인터넷 미디어 기술이 발달하고 개인형 스마트기기(스마트폰, 태블릿PC 등)가 확대 보급됨에 따라 TV 시청행태가 변하고 있다. TV를 시청하면서 개인형 스마트기기를 이용하여 타매체를 동시 이용하는 시청행태가 증가하고 있다. 이러한 시청행태에 대응하여 세컨드스크린 서비스 기술이 주목 받고 있다. KBS는 콘텐츠 사업자 친화적인 세컨드스크린 서비스 기술에 대해 연구하고 TV 친구라는 의미의 세컨드스크린 서비스 플랫폼인 티벗(TVUT) 플랫폼을 개발하였다. 티벗 플랫폼은 이용자 증가에 따른 시스템 확장성과 서비스의 안정성을 고려하여 클라우드 기반 서비스 플랫폼으로 구축하였다. 본 논문에서는 방송 콘텐츠 관련 부가정보를 쉽게 제공할 수 있는 시스템과 서비스 기술을 제시한다.