• 제목/요약/키워드: outer space environment

검색결과 79건 처리시간 0.029초

수중통신에서 Zero Forcing기법을 이용한 최적의 시공간 부호화 알고리즘 (An Optimal Space Time Coding Algorithm with Zero Forcing Method in Underwater Channel)

  • 권해찬;박태두;천승용;이상국;정지원
    • 한국항해항만학회지
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    • 제38권4호
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    • pp.349-356
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    • 2014
  • 수중통신에서는 다중경로로 인해 심벌간의 상호간섭이 발생하여 시스템의 성능을 저하시킨다. 최근 수중 통신시스템에서는 이러한 열악한 채널환경을 극복하고 전송률을 향상시키기 위하여 등화기 및 채널 부호화와 시공간 부호화 방식의 효율적인 연접 구조가 수중통신에서 MIMO시스템으로 응용되어 연구되고 있다. 수중 MIMO 환경에서 시공간 부호화 방식 중에서는 시공간 블록 부호화 방식과 시공간 격자 부호화 방식이 있으며, 시공간 격자 부호화 방식이 등화기 및 채널 부호화 방식에 최적이다. 따라서 본 논문에서는 다중경로 채널 환경에서 효율적인 전송을 위해 터보 Pi 부호화기를 외부부호로 사용하고, MIMO시스템에서 전송 다이버시티와 부호화이득을 동시에 가지는 시공간 격자부호를 내부부호로 구성한다. 그리고 심볼간 상호 간섭 제거를 위해 Zero Forcing 등화기법을 사용하여 수중채널에서의 시뮬레이션을 통해 성능을 확인하였다.

독일 공동주택 놀이터의 친환경적 특성 연구 (A Study on the Eco-friendly Properties of Apartment Housing Playground in Germany)

  • 김자경
    • 한국실내디자인학회논문집
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    • 제24권5호
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    • pp.87-98
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    • 2015
  • As an apartment house as well as improving quality of life is becoming one of the brands, it is increasing the importance of the outer space with the facilities in the housing complex. In particular, the outdoor playground such as the community facilities that children and adults share as the activity areas for residents has received attention. However, actually children have not used many of Korean apartment housing playgrounds that were installed formally in the scrap area according to the housing plan by residential construction standards. it is considered necessary to improve the quality of the playground in housing complex and reform it in order to make the eco-friendly play space in which children can play safely and h healthily. As an alternative, we analyzed the eco-friendly properties of the playgrounds installed in the eco-friendly housing complex in Germany and derived the main planning elements of eco-friendly playground. In the observational survey of the 10 playgrounds in 9 housing complexes in 5 regions in Germany, we evaluated the environment-friendliness of these playgrounds in the 8 fields(location and placement, ecological environment, play space, play equipment and facilities, additional facilities, materials and resources, energy saving, environmental load reduction) according to the levels(suitable, partial reflection, unsuitable, non-reflection) of reflection of eco-friendly planning factors. The following is the summary of the results about the reflection of eco-friendly planning factors. In terms of "suitable": location and placement(88.8%), play equipment and facilities(73.5%), additional facilities(60.6%), environmental load reduction(54%), and ecological environment(50%) were higher than others. In terms of "unsuitable": there was nothing. In terms of "non-reflection": energy saving(95%), additional facilities(32.2%), and materials and resources(30.9%) were in order. Therefore, on the basis of these results, this study proposed the planning indicators to be considered first and the planning factors that should be complemented and improved in the construction of apartment housing playground in future.

지붕일체형 PV모듈의 건축특성 및 적용사례 분석연구 (A study on the Architectural Condition and Cases of BIPV-module for Roof)

  • 이응직
    • KIEAE Journal
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    • 제6권3호
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    • pp.49-56
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    • 2006
  • The roof among the outer surfaces of buildings is an optimum place to install PV since it is the best favorable part in the building to be exposed to day light. Especially, in case of module of BIPV for Roof, it should have essentially the functions of both electricity generation and roof-finish as a construction material. The followings are the results of the study which has analyzed the architectural conditions and applications thereof at the job site. -The aesthetic function of BIPV module is very important because the roof, mostly located at the top of the buildings, is easily recognized and affects outer interior design of the building a lot. -The heat proof of BIPV for Roof could affect the energy consumption through the roof having a wide area. -For architectural condition to the weather, the roof has to ensure the stability of the weather, humidity proof, and airtightness to the wind respectively. -For architectural condition of the structure, endurance by physical power such as stability of both combining and fixing and transfer of load should be ensured. -For residents protection, it has also architectural functions to secure for the space and shield ozone, UV and noxious substances. -Through its practical applications, It is already confirmed that there are various types of BIPV modules overseas and its application has been proved successfully.

생울타리 식재 패턴의 선호도에 관한 연구 (A Study on the Preference of the Hedge Planting Pattern)

  • 최연철;김진선
    • 한국조경학회지
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    • 제25권3호
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    • pp.234-245
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    • 1997
  • This study aims to clarify the preference of the hedge, on focusing the height, density, width of the hedge, which gives limited dwelling space continuity with outer space, promotes the naturality to dwelling environment, and plays an important role as green space in city. For this, it is performed statistical analysis by field survey, by classifying the hedge as planting pattern, and synthesizing the photograph. Therefore, the results of this study are as follows : 1. In the preference of height of the hedge, when only the hedge is composed, 1.5M is preferred, and when the hedge with deciduous tree, with needle-leaf tree, 1.25M is preferred. 2. In the preference of density of the hedge, which are perfect density, in case of the hedge, which are almost density, in case of the needle-leaf tree, are preferred. 3. In the preference of width of the hedge, 0.4M is preferred. 4. In the preferential factors of the hedges, the preference of the hedge is mainly influenced by density. As the result of multiple regression analysis of visual preference as the height, the density, the width, and the regression equation are as follows : Visual Preference = 0.094+0.412(density)+0.370(height)+0.177(width)

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도심복합시설의 공간용도구성 특성에 관한 연구 (Study on the Space Composition Characteristics in the Urban Complex Building)

  • 이강희;채창우
    • KIEAE Journal
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    • 제10권1호
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    • pp.109-116
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    • 2010
  • The city means not only a geographical area as a role of the spatial boundary, but also a socio-economic place to communicate with each area. It requires various functions to get the income and economic-activities. But city has a limitation of a available land to provide the required functions and a sufficient space to supply the urban activity. Therefore, the development trend of city has not been to spread to the horizontal area any more and considered the vertical area. In addition, various functions put into a massive building because many people want to solve the daily requirements without spending time and cost in outer area. In this paper, it aimed at classifying the mixed-use building into function, circulation, relation according to the public and private space and the building shape to provide the design information such as land area, functional complex, accessibility, etc.. The classification of the mixed-use buildings is divided into four areas. The data are collected with foreign countries in Japan, Europe and US. Results of the study are as follows; First, the commercial function is mainly centered with other functions. Second, after studied the development scale, accessibility, building form, the commercial and residential area overwhelmly share at the total area.

우주환경에서 대형 반사경의 습기 방출에 의한 형상 변화 예측방법 (Prediction Method for Moisture-release Surface Deformation of a Large Mirror in the Space Environment)

  • 송인웅;양호순;김학용;김성희;이회윤;김석환
    • 한국광학회지
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    • 제29권4호
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    • pp.166-172
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    • 2018
  • 본 논문에서는 우주의 진공환경에서 반사경 코팅이 흡수한 습기를 방출하면서 나타나는 경면 형상의 변화를 예측하기 위한 새로운 방법론을 제안한다. 직경 50 mm, 두께 1.03 mm의 원형 시편과 간섭계를 통해 진공환경에서 나타나는 시편 형상 변화량을 측정하고 제르니케 프린지 다항식(Zernike fringe polynomial) 곡률항으로 나타내었다. 그 결과 습기 방출에 따른 코팅 스트레스는 152.7 Mpa로 계산되었다. 계산된 스트레스는 1.25 mm 두께 시편의 수치모사 모델에 적용하여 변화된 형상의 곡률항을 측정결과의 표준편차 이내($78.9{\pm}5.9nm$)로 예측할 수 있음을 검증하였다. 이 방법론을 2019년에 발사 예정인 차세대중형위성의 직경 600 mm 쌍곡면경에 적용, 습기 방출에 의한 경면 형상 변화를 계산하여 반사경의 초점거리가 약 $2.005{\mu}m$ 만큼 ?아짐을 예측하였다. 초점거리 변화는 광학 탑재체의 MTF를 한계공간주파수(Nyquist frequency)에서 2.3% 가량 낮추지만, 요구 사양을 만족하여 우주에서도 문제없이 운용 가능함을 확인하였다.

Ultraviolet Properties of Dwarf Galaxies in Fornax Cluster and Ursa Major Group

  • Lee, Young-Dae;Rey, Soo-Chang;Pak, Mi-Na;Kim, Suk;Sung, Eon-Chang;Yi, Won-Hyeong;Chung, Ji-Won
    • 천문학회보
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    • 제35권2호
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    • pp.42.1-42.1
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    • 2010
  • We present ultraviolet (UV) photometric properties of dwarf galaxies in Fornax cluster and Ursa Major group in comparison with Virgo cluster using GALEX data. We construct UV color-magnitude relations (CMRs) of dwarf galaxies matching with available optical photometry and SDSS data. Majority of dwarf galaxies in Fornax cluster show sequence in UV CMRs consistent with that of dwarf elliptical (dEs) in Virgo cluster indicating similar age and metallicity properties of dEs in two clusters. The dS0 sequence in Fornax cluster is not distinct as much as that in Virgo cluster. Dwarf galaxies in outer region of the Fornax cluster show more bluer UV colors with a wide scatter in CMRs, which indicates recent star formation activity. We show that the UV colors of dwarf galaxies are related with the distribution and strength of the X-ray emission in the cluster. In contrast to the Fornax cluster, most dwarf galaxies in Ursa Major group are located in the blue cloud showing recent or on-going star formation, and few galaxies show characteristics of dEs. We discuss relationship between UV properties of dwarf galaxies and different environment of cluster.

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토지이용의 지각특성을 고려한 농촌경관 선호성 분석에 관한 연구 (Analysis of landscape preference based on the perception of rural randuse patterns)

  • 서주환;최현상
    • 농촌계획
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    • 제4권2호
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    • pp.29-40
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    • 1998
  • The landscape of rural settlement incurred the loss and worsening of its main feature in the modernization which was progressed by the inner and outer cause - the growth of urbanization and improvement of living and dwelling environment. This study investigates the visual characteristic of land-use in rural and analyzes relations between visual quantities by land-use and a pre(essence of landscape. And it is suggested the basic data of a planning and a management in rural by making clear characteristics and influences of landscape preference elements The visual characteristic of landscape elements that is based on the rural land-use is classified harmony, variety, variables and particulate. And it is classified the object of landscape by recognizing images of landscape produce space, natural environment, settlement place and cultivated land of a special products. In the analysis of landscape preference, it appears that the harmony has a great influence on a suburban, a rural, a mountainous district, and a hamlet in psychology elements and the volume of forest area in visual elements. As a result, it requests rural scenes in harmony with the natural environment. So, the landscape planning which has the regional development and the identity as the rural settlement can be represented by the preservation and development of regional feature.

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외기에 면한 초고층 아파트 천정 내부결로 예측 (Forecast on Internal Condensation at Ceiling of Super-high Apartment Building Faced with Open Air)

  • 안재봉;송영웅;최윤기
    • 한국건설관리학회:학술대회논문집
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    • 한국건설관리학회 2003년도 학술대회지
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    • pp.626-629
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    • 2003
  • 본 연구는 외기에 면한 초고층 아파트 최상층부의 발코니 천장내부에 있는 H-Beam(내화피복+단열재로 구성)과 Parepet 부위 내부결로 발생가능성에 대한 예측을 해 봄으로써 해당공간 거주자의 쾌적한 환경 만족 및 불안을 해소 하는데 그 목적이 있다. 외주부를 성하고 있는 Curtain wall, Stone panel 또는 슬래브 바닥하부 등의 열적 취약공간에 대해 2차원 정상상태(온도평형) 열전도해석 Program을 이용, 온도예측과 온도분포해적을 통해 해당부위의 습기압분포에 따른 내부결로 예측을 실시하였다.

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HVDC 가공 송전선로 전기환경특성 모의시험용 코로나 케이지 계측시스템 개발 (Development of Corona Cage Measurement System for Simulation on Electrical Environmental Characteristics of HVDC Overhead Transmission Line)

  • 길경석;양광호;이성두;주문노
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제55권5호
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    • pp.245-249
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    • 2006
  • Corona characteristics of conductors are dependent on the electric field conditions in the immediate vicinity of the conductors. In case of DC transmission line, particularly, the space charge plays an important role in the electric field distribution. Therefore, DC corona cage simulation is necessary for long-term test in the same conditions. This paper presents the results of designing and constructing hardwares such as DC power supply, measurement system and DAS to carry out the simulation. The corona cage longitudinally is divided into five equal length sections and three inner sections of those are isolated from the ground of outer cage. The measurement items are radio noise, corona current, television noise, audible noise and meteorological conditions. In the next step, various simulations about the type and configuration of two or three candidate conductors will be conducted. And then finally an environmentally-friendly conductor for HVDC overhead transmission line will be decided.