• Title/Summary/Keyword: Optical Internet

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Next Generation Internet Based on Optical Switching Technology (광스위칭 기반 차세대 인터넷)

  • Hahm, J.H.;Kang, S.G.;Park, K.S.;Park, C.H.
    • Electronics and Telecommunications Trends
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    • v.16 no.2 s.68
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    • pp.10-30
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    • 2001
  • 본 고에서는 차세대 인터넷 구축을 위한 요소 기술에 대하여 전반적으로 살펴본다. 우리는 현재보다 1,000배 빠른 차세대 인터넷의 구축을 목표로 하고 있다. 따라서 과연 그만큼 빠른 인터넷의 구축이 필요할 것인가를 검증하는 차원에서 향후 5년 정도의 가까운 시일 내에 있을 인터넷 트래픽의 증대에 대한 수요를 서비스 측면에서 살펴본다. 차세대 인터넷은 풍부한 전송대역폭의 제공과 QoS를 기반으로 한 신뢰성 있는 데이터의 전달을 특징으로 하며, 이를 위해서 광스위칭 기반의 전송 하부구조 위에 MPLS 기술이 사용될 것으로 예상된다. 이를 위한 요소기술로 DWDM 전송기술, MEMS 기반의 광스위칭 소자기술과 함께 광스위칭 기술에 지능을 부여하기 위한 표준화 동향에 대하여 살펴본다. 현재의 IP 기반 인터넷에서 제공하지 못하는 QoS 기능은 MPLS에서 가능하게 될 것이다. MPLS에서의 중요한 응용인 트래픽 엔지니어링과 VPN 서비스는 망이 보다 안정적으로 유지될 수 있도록 지원하면서 기업들이 MPLS 망을 이용하여 자신의 망을 구축할 수 있도록 지원할 것이다. MPLS 기술은 IETF에서 표준화가 진행되고 있으며 라우터 개발업체 및 ISP의 큰 지원을 받고 있다. 차세대 인터넷을 위해서는 전달망의 구축도 필요하지만 이와 함께 차세대 인터넷 응용을 위한 컴퓨팅 인프라도 균형있게 개발되어야 한다. 따라서 현재 그 윤곽을 드러내고 있는 차세대 인터넷 응용 인프라 환경에 대하여 그 등장 배경과 관련 기술에 대하여 조망한다. 차세대 인터넷의 개발을 위해서는 광처리 관련 원천 기술, 프로세서 개발 기술, 라우터 설계 기술 및 서버 개발 기술, 어플리케이션 기반 기술 및 사용자 인터페이스 기술들이 전략적으로 이음새 없이 매끄럽게 통합되어야 한다. 이러한 관점에서 필요한 요소기술들을 다수 보유하고 있는 ETRI의 역할은 매우 중요하리라 생각된다.

SHORT-PERIOD VARIABILITY SURVEY (SPVS) IN BOAO (보현산천문대 단주기변광성 탐사(SPVS)연구)

  • Jeon, Young-Beom;Kim, Seung-Lee;Park, Yoon-Ho;Park, Byeong-Gon;LeeK, Chung-Uk;Lee, Eun-Jeong;Kim, Min-Su;Lee, Kyung-Hoon
    • Publications of The Korean Astronomical Society
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    • v.20 no.1 s.24
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    • pp.21-27
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    • 2005
  • We have been performing a wide-field photometric monitoring program, named SPVS (Short-Period Variability Survey), at the Bohyunsan Optical Astronomy Observatory (BOAO). The observation system consists of a small refracting telescope (D = 155 mm, f = 1050 mm) and a $2k{\times}3k$ CCD Camera. The field of view is $1.0^{\circ}{\times}1.5^{\circ}$. Detection limit is about V = 13 for short-period small amplitude variables such as ${\delta}$ Scuti-type pulsating stars, and about V = 15 for long-period large amplitude variables such as eclipsing binaries and RR Lyrae stars. The instrument is designed to be remote-controlled through internet. The primary purpose of this project is to search for variable objects in bright Galactic open clusters. We present results of test observations conducted towards NGC 7092.

Handover Call Admission Control for Mobile Femtocells with Free-Space Optical and Macrocellular Backbone Networks

  • Chowdhury, Mostafa Zaman;Saha, Nirzhar;Chae, Sung-Hun;Jang, Yeong-Min
    • International journal of advanced smart convergence
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    • v.1 no.1
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    • pp.19-26
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    • 2012
  • The deployment of mobile femtocellular networks can enhance the service quality for the users inside the vehicles. The deployment of mobile femtocells generates a lot of handover calls. Also, numbers of group handover scenarios are found in mobile femtocellular network deployment. The ability to seamlessly switch between the femtocells and the macrocell networks is a key concern for femtocell network deployment. However, until now there is no effective and complete handover scheme for the mobile femtocell network deployment. Also handover between the backhaul networks is a major concern for the mobile femtocellular network deployment. In this paper, we propose handover control between the access networks for the individual handover cases. Call flows for the handover between the backhaul networks of the macrocell-to-macrocell case are proposed in this paper. We also propose the link switching for the FSO based backhaul networks. The proposed resource allocation scheme ensures the negligible handover call dropping probability as well as higher bandwidth utilization.

Performance Evaluation of control and management protocol for Dynamic lightpath setup based GMPLS network (GMPLS 기반의 동적 경로 설정을 위한 제어 및 관리 프로토콜 성능 평가)

  • Kim Kyoung-Mok;Oh Young-Hwan
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.41 no.12
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    • pp.9-14
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    • 2004
  • As the internet traffic type and size have bun diversified in recent years, the GMPLS-based distributed control and management protocol have surfaced as a serious issue for dynamic optical lightpath setup. In this reason, we investigated and analyzed network performance and protocols using global information-based link state approach and local information based link state approach. We calculated connection setup time, required control bandwidth and setup blocking probability that made from network update period and threshold metrics according to traffic arrival rate. The evaluated results will be used in broadband network and adopted for high speed network in the future widely.

Avatar Application for Fashion Cyber Education - Focused on Optical Illusion of Design Elements according to Body Shapes - (패션 사이버 교육(敎育)을 위한 아바타 제작(製作)및 활용(活用) - 체형(體型)에 따른 디자인요소(要素)의 착시효과(錯視效果)를 중심(中心)으로 -)

  • Lim, Hyun-Jung;Park, Hye-Won
    • Journal of Fashion Business
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    • v.9 no.4
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    • pp.1-15
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    • 2005
  • Interesting education which utilizes cyber visual and audio multimedia effects, we regard it as a very effective education but those programs are not prepared yet. So, the purpose of this research is to provide a new direction for cyber fashion education with the use of avatars as the multimedia factor to increase student's interest and understanding. First, we investigated the present situation of fashion cyber education and the present avatar usage situation online, and also we searched literature and the internet to investigate the general theory of design. Second, we used Adobe photoshop 7.0 to make avatars, then, we used Macromedia Flash MX to design the avatar on our web site, and to make it look more realistic. According to the research results, cyber fashion education is usually used as marketing in certain areas, and for middle school, and high school students it is mainly used as text and lecture videos. When searching for fashion sites that use avatars, we found that most fashion shopping malls use them. Because avatars can give visual effects and also increase interest and fun, they can increase concentration and understanding and can be effective in fashion cyber education.

A Study of Housing Design Guidelines for the Single Household (독신 가구의 주거계획 방향에 관한 연구)

  • Cho, Myung-Eun
    • Journal of Families and Better Life
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    • v.20 no.6
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    • pp.219-227
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    • 2002
  • This study was conducted to examine housing preferences among single-person households and to propose guidelines for housing design choices for single people. One hundred and sixty responses to the questionnaire developed by this researcher were analyzed utilizing frequencies, percentages, and t-tests. There were significant differences between single households and non-single households in various aspects of housing preferences. Differences were found in the desired type and size of housing, needed amount of space, and the importance of space itself. Single persons wanted to live in a small apartment, about 83.45$m^2$ (25.29 pyung) size. They consider the bathroom and the master bedroom more important than the living room and kitchen. They prefer to have specifically function-oriented rooms such as shower, home office, computer room, exercise room, or leisure space. Single persons consider information-technological facilities within an apartment very important. They would like to adopt automatic and electronic technology in the house, such as optical communication network, automatic air-cleaning system, and internet TV. Housing preferences differ significantly according to socio-demographic variables such as gender and age. I propose in this study a small-sized, information-, high-tech- and leisure-oriented design that corresponds with the actual housing preferences of the single-person households.

A Study on Path Selection Scheme for Fast Restoration in Multilayer Networks (신속한 다계층 보호 복구를 위한 경로선택 방식 연구)

  • Cho, Yang-Hyun;Kim, Hyun-Cheol
    • Convergence Security Journal
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    • v.12 no.3
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    • pp.35-43
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    • 2012
  • The explosive growth of Internet traffic cause by smart equipment such as smart phone has led to a dramatic increase in demand for data transmission capacity and network control architecture, which requires high transmission rates beyond the conventional transmission capability. Next generation networks are expected to be controlled by Generalized Multi-Protocol Label Switching(GMPLS) protocol suite and operating at multiple switching layers. In order to ensure the most efficient utilization of multilayer network resources, effective global provisioning that providing the network with the possibility of reacting in advance to traffic changes should be provided. In this paper, we proposes a new path selection scheme in multilayer optical networks based on the vertical PCE architecture and a different approach to efficiently exploit multiple PCE cooperation.

Characteristic Changes of Layered Techniques in the Hussein Chalayan's Collections (후세인 샬라얀 컬렉션에 나타난 레이어드 기법의 변화 특성 연구)

  • Koo, Mi-Ji
    • Journal of the Korea Fashion and Costume Design Association
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    • v.9 no.3
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    • pp.221-230
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    • 2007
  • This research was focused on the changes of layered techniques in Hussein Chalayan's collections. For this purpose, the layered techniques in 134 works from Chalayan's collections, 97S/S to 06S/S, which were obtained from fashion magazines and fashion internet site, were analyzed and classified into 15 groups. Layered techniques in his works apparently expressed his philosophy about deconstruction. Multilayered feeling was given through using various techniques such as one layer clothing which was showed like multi-layered clothing. Others were multi-layer clothing which felt like one layer, breaking the stereotyped line of clothing into atypical construction and using various materials or constructive lines which made the optical feeling like one layer or multi-layer clothing, and so on. These layered techniques in Chalayan's collections were differentiated into several categories, such as techniques which were revealed in every collections, techniques which were differentiated from one another collections, techniques which were continuously showed through three collections for connection with each collection, techniques which were used only for Spring/Summer season, and techniques which were uniquely showed in early collection or recent collections.

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On the Pulse Diagnosis via a Thread, Namely "Xuanxizhenmai" (실을 통한 맥진, 소위 현사진맥(懸絲診脈)에 관하여)

  • Choi, Sung-Min;Kim, Ki-Wang
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.16 no.1
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    • pp.1-8
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    • 2012
  • Objectives Although the faith that pulse diagnosis via a thread, namely "Xuanxizhenmai", had been applied to some women in royal families, is widely spread in East Asian countries, but it is still controversial that whether this faith is based on historical facts or just originated from some folk tales. So we provided some reasonable clues to interpret that faith. Methods The digitalized Annals of Joseon Dynasty and Twenty Five Books of Chinese History were used for historical example search. Conventional internet search engines are widely used for investigation of other examples and related interpretations. Additionally, a pilot observation with nylon threads and optical vibration detection devices was performed to confirm it's feasibility. Results Although there are a few evidences supporting Xuanxizhenmai's existence in Qing dynasty, no evidence was found to show it's existence in authoritative annals of Korea and China. The pilot observation showed that in optimal environment, some intense arterial pulse could be propagated dozens of centimeter, but it was not applicable to clinical needs. Conclusions Pulse propagation via a thread was proved to be reproducible within limited extents, but pulse diagnosis via a thread, namely Xuanxizhenmai, seem to have never been used for proper clinical purpose.

Development of HDF Browser for the Utilization of EOC Imagery

  • Seo, Hee-Kyung;Ahn, Seok-Beom;Park, Eun-Chul;Hahn, Kwang-Soo;Choi, Joon-Soo;Kim, Choen
    • Korean Journal of Remote Sensing
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    • v.18 no.1
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    • pp.61-69
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    • 2002
  • The purpose of Electro-Optical Camera (EOC), the primary payload of KOMPSAT-1, is to collect high resolution visible imagery of the Earth including Korean Peninsula. EOC images will be distributed to the public or many user groups including government, public corporations, academic or research institutes. KARI will offer the online service to the users through internet. Some application, e.g., generation of Digital Elevation Model (DEM), needs a secondary data such as satellite ephemeris data, attitude data to process the EOC imagery. EOC imagery with these ancillary information will be distributed in a file of Hierarchical Data Format (HDF) file formal. HDF is a physical file format that allows storage of many different types of scientific data including images, multidimensional data arrays, record oriented data, and point data. By the lack of public domain softwares supporting HDF file format, many public users may not access EOC data without difficulty. The purpose of this research is to develop a browsing system of EOC data for the general users not only for scientists who are the main users of HDF. The system is PC-based and huts user-friendly interface.