• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.4A
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• pp.528-538
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• 2000

Mobile computing system requires both precise identification and secure authentication scheme on remote mobile entities, which is based on the distributed mobile node. In this paper, existing discrete logarithm based $Schnorr^{[7]}$ like entity authentication schemes are improved by the analysis of performance and security on the hi-directional interactive proofs. And $EIGamal^{[14]}$ like efficient authentication schemes are also proposed. Then, these are enhanced with oblivious transfer based mono directional authentication schemes based on trusted third party for applying to the mobile agent based computing systems. Therefore, proposed schemes provide compatible performance and safety on mobile entity authentication processes.

• Geophysics and Geophysical Exploration
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• v.11 no.4
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• pp.373-378
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• 2008

Being widely used for preparation of geographic maps in the field of earth sciences, Generic Mapping Tools (GMT) is difficult to understand the contents for user, and not working well with Microsoft (MS) Window PC. By utilizing R package, 'GEOmap', we can do mapping work at MS window PC with commands easier than those of GMT. In addition, the R commands offer interactive help. Here we introduce brief feature of 'GEOmap', and illustrate the procedure for preparing tomographic maps with an example.

• Journal of Broadcast Engineering
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• v.2 no.2
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• pp.182-193
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• 1997

In this paper, we propose technical and structural solutions for various problems in two-way digital communication services in CATV networks by actual field tests. The two-way digital communication services include VOD, video conferencing, distance learning, interactive game and internet service. We investigate the quality of T -1 level 0.544 Mbps) upstream digital signal while varying the number of subscribers in three different cells in accordance with ITU-T G.821. Based on this investigation, several ways to cope with the problems identified are suggested.

• Journal of the Korean housing association
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• v.16 no.4
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• pp.45-55
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• 2005

The cubist collagists proposed radically different ideas about the nature of order, and about the nature of artistic space. The collage substitutes an order which is constructed on relationships for the more rigid order of traditional art. Collage presents new theories of communication with the viewer, of relationships and of signs. This paper is an investigation of these ideas and how they have been applied to Mies Van der Rohe's making of architecture: Barcelona Pavilion and Tugendhat house. Collage in Mies' works has been executed in a limited manner. In Mies' works, one can begin to recognize some basic traits of collage. Textures, forms, and fragments begin to interact with each other and exploit those principles of contrast and juxtaposition that give collage a value as an expressive medium. Many of the formal aspects of collage are readily apparent in much of the work which we see around use today, but we should look at the attitudes and beliefs upon which collage is built for a further understanding of how its principles can be applied.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.8B
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• pp.482-491
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• 2007

This paper proposes a k-disjoint-path routing algorithm that provides energy efficient and reliable message transmission in wireless sensor networks. The proposed algorithm sends messages through a single path without the occurrence of critical events. However, it sends through k disjoint paths(k>1) under the occurrence of critical events. The proposed algorithm detects the occurrence of critical events by monitoring changing data patterns, and calculates k from a well-defined fault model and the target-delivery ratio. Our simulations reveal that the proposed algorithm is more resilient to node failure than other routing algorithms, and it also decreases energy consumption and reduces the average delay much more than multi-path and path-repair algorithms.

• Proceedings of the Korea Institute of Convergence Signal Processing
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• 2005.11a
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• pp.256-259
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• 2005

운세정보 서비스는 전화로 일반 사용자들이 많이 이용하고 있지만 사용자들이 이용하기에 너무 비싸고 서비스 제공자가 항상 대기해야한다는 단점이 있다. 이점을 보완하는 웹서비스가 있지만 언제 어디서나 이 서비스를 활용할 수는 없다. 그래서 VoiceXML을 이용한 운세정보서비스를 구현하였다. VoiceXML은 음성을 웹 페이지처럼 작성할 수 있는 언어이고 웹과도 호환성이 좋아 기존 웹 서비스의 기능을 모두 지원하면서 독립적으로 음성 인터페이스를 제공해 전화와 웹 서비스의 장점을 모두 취할 수 있다. 본 연구에서는 웹 서비스중 오늘의 운세, 궁합, 바이오리듬, 타로카드점을 VoiceXML을 이용하여 구현했다. 12인의 피 실험자가 각 메뉴를 모두 2번씩 실험한 결과 95%이상의 동작 성공률을 보였다. 그리고 실험자에 대한 설문조사 결과 기존 웹 서비스에 비해 범용성과 경제성 면에서 장점을 갖는다는 결과가 나왔다. 앞으로 입력부분에 대화형 서비스 메뉴를 보완하여 더욱 사용이 편리한 서비스로 개선할 계획이다.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.11 no.2
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• pp.60-66
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• 2001

($Ba_x$$Sr_{1-x}$)$TiO_3$ (x=0.9, 0.7, 0.5) thin films were prepared on ITO-coated glass by sol-gel method. Perovskite phase formation temperature of BST thin films seemed to be higher than $600^{\circ}C$. Peaks of perovskite phase shift to high diffraction angles as the Sr/(Ba+Sr) ratio was increased, due to the smaller ionic size of $Sr^{2+}$ than $Ba^{2+}$ . As a heating temperature was increased, the grain became coarser. And as Sr/(Ba + Sr) ratio was increased, the grain became finer. Dielectric constants of the BST(50/50) thin film are higher and dielectric losses of that are lower than those of the others. Dielectric constant and dielectric loss of the BST(50/50) thin film were 652 and 0.042 at 1kHz, respectively.

• The Transactions of the Korea Information Processing Society
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• v.4 no.9
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• pp.2403-2411
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• 1997

Direct3D is a recently developed 3D graphic accelerator such that we could make a Windows graphic programs with Direct3D easily. This paper presents the fractal terrain model viewer developed in terms of Direct3D. The object classes and the input dialog box used the model viewer, program initializing process, and the flow of the model viewer are discussed. Finally, the output of terrain formulation in wire-frame, solid, and point type form are presented. To show the results, the data of a terrain model were made by a fractal technique, the midpoint displacement methods with square lattices of points.

• Proceedings of the Korean Information Science Society Conference
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• 2005.11a
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• pp.814-816
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• 2005

현재 까지 지능형 자동차의 서비스 형태는 주로 차량 운전자에 대한 유용한 정보제공과 엔터테인먼트를 중심으로 연구 되어 왔다. 그러나 유비쿼터스 환경에서의 지능형 자동차와 같이 시간과 장소의 구애됨없이 언제 어디서든 자동차와의 대화와 제어가 가능한 서비스 제공에는 많은 제약 사항을 가진다. 본 논문에서는 CDMA 이동통신망을 이용하는 웹기반 차량 무선원격제어 및 진단을 위한 지능형 차량정보시스템을 설계 및 구현 하였다. 구현한 지능형차량정보시스템은 언제 어디서든 웹브라우져를 통하여 원격지 차량의 제어와 진단이 가능하며, 제어 조작자와 차량 간의 이동성을 제공하다. 뿐만 아니라 인터넷 상의 차량제어서버를 이용하여 차량 진단을 위한 과거 차량 상태 내역을 제공해 줄 수 있기 때문에 보다 효과적인 차량 원격제어와 진단이 가능한 장점을 가진다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.9 no.5
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• pp.45-51
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• 2009

In this paper, we propose a multiplex channel shopping mall services using IPTV. The main idea and features are as follows. First, we suggest bi-directional conversation channel instead of conventional unidirectional channel. Currently shopping mall broadcast services are one sidedly provided by commercial company. In these kinds of methods, efficient communication of information between commercial company and users is difficult problem. In this paper, we can solve this problem by using IPTV technology. Second, we can create new profit model by using combination of both the advantages of internet shopping mall and the advantages of cable TV shopping mall.