• Title/Summary/Keyword: 에너지 공간

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A Study on Metadata for Sharing the Information of Earth Observation (지구 관측자료 공유를 위한 메타데이터 연구)

  • Lee, Hye-Young;Kwak, Seung-Jin
    • Journal of the Korean Society for Library and Information Science
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    • v.41 no.2
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    • pp.257-276
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    • 2007
  • The purpose of this study is to design the metadata for sharing and efficiently using the informations of Earth Observations in Korea. Recently the GEO(Group on Earth Observations) has been starting to manage all nation's informations in a way that benefits the environment as well as humanity by taking a pulse of the plants. For that reason, we have to construct the infra-system to manage and integrate the 12 social benefit areas in Korea; disaster, health, energy, climate, water, biodiversity, agriculture, forest, ocean, space information and geographical information system(GIS). But these informations have only been managed with varied metadatas in each area of observation, and then it is difficult to integrate varied informations. In this study, we solve the problem with meta-metadata.

A Study for the Screen Door System Driving Stiffness of Motor Control Method (모터 제어 방식의 스크린 도어 시스템 구동강성 검증)

  • Lee, Jung-Hyun;Lee, Seon-Bong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.4
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    • pp.2385-2390
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    • 2015
  • In the beginning run, urban railway had been required as transportation. But now days urban railway have stayed in the platform for long time, the platform is faced the problem that is improvement of environment as one of the living space. Thus, sliding automatic door on the basis of screen door have used in huge distribution market, hospital, restaurant and public office because it is comfortable that customer's convenience and entrance are controled. So screen door not only requires customer's convenience and safe, clean area and energy conservation but demands optimal design technology development of screen door system that is confirmed by element parts of design and confidence. In this paper, For secure confidence of screen door, after as modeling roller and frame's system, confirming the result for qualification of driving stiffness. And then it suggests that it is possible to increase performance and declines fraction defective of element's part.

Analysis of Characteristics of White LED Light Source for TV Lighting (TV 조명용 백색 LED의 광원 특성 분석)

  • Lee, Kook-Se;Moon, Nam-Mee
    • Journal of Broadcast Engineering
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    • v.15 no.4
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    • pp.461-473
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    • 2010
  • Since eco friendly and power saving products recently got into the limelight for the protection of environment, LED light technology has caught much of attention as the next generation broadcasting lighting. The newly introduced light source has such advantages as higher efficiency, longer life and its slim and compact forms leading to conveniency in installations. When combined with digital light control it gives more dynamic and various features to lighting. In this paper, used CIE standard for measuring light sources by their purposes and forms to make a comparative analysis of spectral distribution and color rendition of LED light source to those of existing lighting systems. By means of the cast shadowing and color reproduction tests I also tried to figure out the effects of LED lighting design on TV visuals where higher quality is crucial with the audience's increasing demands for quality image.

A Numerical Study of Radiation Effect under Smoke Movement in Room Fire (실내화재에서 연기거동에 미치는 복사영향에 대한 수치해석적 연구)

  • 정진용;유홍선;홍기배
    • Fire Science and Engineering
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    • v.14 no.3
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    • pp.6-12
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    • 2000
  • This paper describes the smoke movement of a fire field model based on a self-developed SMEP(Smoke Movement Estimating Program) code to the simulation of fire induced flows in the two types of compartment space containing the radiation effect under smoke movement in room fire. The SMEP using PISO algorithm solves conservation equations for mass, momentum, energy and species, together with those for the modified k-$\varepsilon $ turbulence model with buoyancy term. Also it solves the radiation equation using the discrete ordinates method. The result of the calculated smoke temperature containing radiation effect has shown reasonable agreement compared with the experimental data. On the other hand, a difference of a lot was found between the temperature predicted by the SMEP with only convection effect and obtained by the experimental result. This seems to come from the radiation effect of $H_2$O and $CO_2$ gas under smoke productions. Thus, the consideration of the radiation effect under smoke in fire may be necessary in order to produce more realistic result.

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Approximate Lost Data Recovery Scheme for Data Centric Storage Environments in Wireless Sensor Networks (무선 센서 네트워크 데이터 중심 저장 환경을 위한 소실 데이터 근사 복구 기법)

  • Seong, Dong-Ook;Park, Jun-Ho;Hong, Seung-Wan;Yoo, Jae-Soo
    • The Journal of the Korea Contents Association
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    • v.12 no.7
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    • pp.21-28
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    • 2012
  • The data centric storage (DCS) scheme is one of representative methods to efficiently store and maintain data generated in wireless sensor networks. In the DCS schemes, each node has the specified data range for storing data. This feature is highly vulnerable to the faults of nodes. In this paper, we propose a new recovery scheme for the lost data caused by the faults of nodes in DCS environments. The proposed scheme improves the accuracy of query results by recovering the lost data using the spatial continuity of physical data. To show the superiority of our proposed scheme, we simulate it in the DCS environments with the faults of nodes. In the result, our proposed scheme improves the accuracy by about 28% through about 2.5% additional energy consumption over the existing scheme.

The Geomorphic Characteristics of Bulguksa-region and the Earthquake Resistant Structure of the Bulguksa Temple (불국사 지역의 지형특성과 불국사의 내진 구조)

  • Hwang, Sang-Ill
    • Journal of the Korean Geographical Society
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    • v.42 no.3 s.120
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    • pp.315-331
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    • 2007
  • Some reverse fault lines are passing through the alluvial fans and west hill slope of Bulguksa mountains including Mt. Toham in the directions of N-S and NW-SE. The study area is known as relatively unstable, because of active faults. Assuming on the record of Samguksagi about earthquakes, the architects in the construction of the Bulguksa Temple should have recognized the possibility of breakdown from the earthquakes and the need for an unique structure against at that time. Against earthquakes, Grengee technique, a stonework construction technique following wooden one and use of Chuduseok(Dongtleseok or Chumchaseok) were applied for the construction of the Bulguksa Temple. By designing the foundation stone with hole, a structure is prevented from modification that pillars secede from a foundation stone in spite of horizontal load of earthquake while wood construction is strong frame at earthquake. The Bulguksa Temple is usually evaluated to be a beautiful architecture from the appearances like the weight balanced structure with unique decoration. Impressive architectures are beautiful in balance and harmony coming from the important and specific rolls in its own way by each part of whole structure. This beauty comes from the science.

Analysis on the interference reduction by smart antenna in CDMA reverse channel (스마트 안테나에 의한 CDMA 셀룰라 시스템의 역방향 간섭 제거에 관한 연구)

  • 정동규
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.23 no.7
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    • pp.1677-1688
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    • 1998
  • In this paper, we analyze the performance of a DS-CDMA system employing adaptive adaptive array antenna technology at base-station. For the analysis the receiving architecture of a multiple team adaptive base-station array antenna is proposed as a major system omponent, and signal to interference and noise ratio(SINR) on the proposed architecture is developed. We show that the perfomance enhancement of the CDMA system is represented as great reduction of interfreence by employing an array antenna capable of resolving the angular distribution of the mobile users as seen at the ase-station. The energy associated with each mobile or a group of mobiles is thus confined within the addressed volume, greatly reducing the amount of co-channel interference experienced from and by neighboring co-channel cells. In order to ascertain the benefits of such an antenna, a theoretical approach, which eis based on the conventional and proposed antenna systems in a typical mobile radio environment, is adopted. Finally computer simulation results show the insight into how the adaptive array antenna operates when used in conjunction with DS-CDMA and illustrate the potential benefits in the SINR point of view.

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Digital Hologram Encryption using Discrete Wavelet Packet Transform (이산 웨이블릿 패킷 변환을 이용한 디지털 홀로그램의 암호화)

  • Seo, Young-Ho;Choi, Hyun-Jun;Kim, Dong-Wook
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.11C
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    • pp.905-916
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    • 2008
  • In this paper, we propose a new method which estimates and encrypts significant component of digital hologram using discrete wavelet packet transform (DWPT). After analyzing the characteristics of digital hologram in spatial and frequency domain, the required information for ciphering digital hologram was extracted. Based on this information an ciphering method was proposed with wavelet transform and packetization of subbands. The proposed algorithm can encrypt digital hologram in various robust from selecting transform-level and energy threshold. From analyzing the encryption effect numerically and visually, the optimized parameter for encryption is presented. Without additional analyzing process, one can encrypt efficiently digital hologram using the proposed parameter. Although only 0.032% among total data is encrypted, the reconstructed object dose not identified. The paketization information of subbands and the cipher key can be used for the entire secret key.

Preparation of Permselective Membrane by Mean of a Radiation-Induced Grafting (방사선 그래프트에 의한 반투막 제조연구)

  • Young Kun Kong;Hoon Seun Chang;Chong Kwang Lee;Jae Ho Choi
    • Nuclear Engineering and Technology
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    • v.15 no.1
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    • pp.1-10
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    • 1983
  • By controlling both the means of grafting and the cast-solution components, no degradation and dimensional change of radiation-induced graft polymerization were found. The electric resistance of styrene-cellulose acetate grafts increases with increasing styrene content, while those for the hydrophilic monomers show no marked effect. In comparison with the grafted cellulose acetate membrane by simultaneous irradiation method, the appearance of the grafted membrane by post-polymerization method was not markedly changed irrespective of the percent of grafting and radiation dose of electron beam or ${\gamma}$-ray. The combination of crosslinking agents such as divinyl benzene (OB) or trimethyl propane triacrylate (TMPT) in the VP:St:BPO system leads to gradual increase of the percent of grafting. The activation energy for grafting of St:VP:BPO solution onto cellulose acetate membrane was determined to be about 21.8 Kcal/mole over the range of 55$^{\circ}$-8$0^{\circ}C$. The initial rate of grafting (in %/hr) is proportional to the power 0.76 for dose intensities.

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Characteristics of the Nd:YAG laser with stimulated brillouin scattering phase conjugate mirror (유도 브릴루앙 산란 위상공액 거울을 이용한 Nd:YAG 레이저 발진기의 출력특성)

  • 이동원;이성구;박승현;공홍진
    • Korean Journal of Optics and Photonics
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    • v.13 no.6
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    • pp.548-553
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    • 2002
  • We have investigated the output characteristics of a Nd:YAG oscillator with a Stimulated Brillouin Scattering phase conjugation mirror (SBS-PCM). FC-75 is used as an SBS gain medium and Cr:YAG (T=50%) as a Q-switcher. The SBS-PCM consists of an SBS-cell and a simple plano-convex focusing lens system. For the case of not using a Q-switcher, an SBS-cell doesn't work as a phase conjugation mirror. For the case of using a Q-switcher, the energy characteristics remains nearly the same whether using the SBS-cell or not using it. The pulse width is reduced from 50 ns to 40 ns by an SBS-PCM. When the SBS-cell is used with a Q- switcher, the SBS-cell works very well as a phase conjugation mirror and its beam-profile is improved dramatically. And in order to explain the progression of beam-profile, we propose a simple model based on the nonlinear reflectivity of the SBS-PCM, whose reflectivity is dependent on the pumping intensity at the focal plane.