• 제목/요약/키워드: wide connection

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고해상도 영상 레이다의 광대역 첩 신호 파형 발생 시뮬레이션과 성능 분석 (Wideband Chirp Waveform Simulation and Performance Analysis for High Range Resolution Radar Imaging)

  • 곽영길
    • 한국항행학회논문지
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    • 제6권2호
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    • pp.97-103
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    • 2002
  • 고해상도 영상레이다에서 초광대역 파형 처리기술은 정밀 표적 식별을 위해서 매우 중요하다. 본 논문에서는 영상 레이다의 거리 분해능을 초 고해상도로 향상시킬 수 있는 방법으로서, 송신 펄스의 첩 변조 파형을 모듈방식으로 확장하여 광대역의 송신 파형을 얻을 수 있는 레이다 첩 파형 설계 기법에 대하여 논한다. 먼저 디지털 첩 신호발생 원리와 광대역 첩 신호 파형을 얻기 위한 신호대역 연결 및 분리 기법을 제시한다. 그리고, 영상 레이다의 거리 해상도 성능분석을 위하여 발생시킨 광대역 신호 파형 발생과 복원과정을 시뮬레이션을 통하여 성능 결과를 제시한다.

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Galaxy Clusters in ELAIS-N1 field

  • Hyun, Minhee;Im, Myungshin;Kim, Jae-Woo;Lee, Seong-Kook;Edge, Alastair C.
    • 천문학회보
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    • 제39권2호
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    • pp.70.2-70.2
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    • 2014
  • Galaxy clusters, the largest gravitationally bound systems, are an important means to place constraints on cosmological models. Moreover, they are excellent places to test galaxy evolution models in connection to the environments. To this day, massive clusters have been found unexpectedly(Kang & Im 2009, Durret et al. 2011, Tashikawa et al. 2012) and evolution of galaxies in cluster have been still controversial (Elbaz et al. 2007, Cooper et al. 2008, Tran et al. 2009). Finding galaxy cluster candidates in a wide, deep imaging survey data will enable us to solve the such issues of modern extragalactic astronomy. We have used multi-wavelength data from the UKIRT Infrared Deep Sky Survey Deep Extragalactic Survey (UKIDSS DXS/J and K bands), Spitzer Wise-area InfraRed Extragalactic survey (SWIRE/two mid-infrared bands), the Panoramic Survey Telescope and Rapid Response System (PAN-STARRS/ g, r, i, z, y bands) and Infrared Medium-deep Survey(IMS/J band). We report new candidates of galaxy clusters and properties of their member galaxies in one of the wide and deep survey fields ELAIS-N1, European Large Area ISO Survey North1, covering sky area of $8.75deg^2$.

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광주(光州) 신창동(新昌洞) 저습지출토(低濕地出土) 나무문짝(비문(扉門))에 관한 연구(硏究) (A Study on the Door Discovered at the Shinchang-dong Wetland Site)

  • 천득염;신상효
    • 건축역사연구
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    • 제15권5호
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    • pp.7-18
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    • 2006
  • A lot of relics were unearthed in the Shinchang-dong wetland site, which can help restore prehistoric life style, including construction tools such as wood doors, wood hammers, ax handgrips, sickle handgrips, wedges, awls, wood pillars and connection members, food vessels made of earth or wood and fish, shell fish, seeds and remains of weapons. In particular, a door was found in the site, which was measured at 110cm long and 37cm wide. If restored it will be 75cm wide. The door seems to date back as far as the 1st century B. C., which would be the oldest one ever discovered in Korea. This paper is intended to explore the implications of the door by investigating the environment of the Shinchang-dong wetland site bearing the relics intact, manufacturing techniques and times of manufacturing of the door as well as attributes of doors presented in the literature related to old time architecture such as Goguryeo tomb paintings and house-shaped vessels. It also intends to provide basic data for study of residential architecture in prehistoric times.

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AKARI Observation of the North Ecliptic Pole (NEP) Supercluster at z=0.087

  • 고종완;임명신
    • 천문학회보
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    • 제35권1호
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    • pp.74.2-74.2
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    • 2010
  • We present a multi-wavelength study of a supercluster in the NEP region at z=0.087, using AKARI (Infrared space telescope) NEP-Wide (5.8 deg2) survey which has obtained an unique IR imaging dataset with contiguous wavelength coverage from 2 to $24{\mu}m$, overcoming the Spitzer limitation of imaging capability at $10-20{\mu}m$. The NEP-Wide survey is also covered in other wavelength such as X-ray, Radio, GALEX UV in the archive, optical (BRI from Maidanak 1.5m and CFHT's MegaPrime), and NIR imaging data (JH from KPNO 2.1m), with nearly 1900 optical spectra, mostly obtained by our group using MMT/Hectospec and WIYN/Hydra. Armed with the multiwavelength datasets, we investigate the connection between IR properties of galaxies and their environments as a tool to understand the evolution of galaxies in a supercluster environment. Specific attention will be given to MIR emission which can trace star formation activities and passive phases right after post-starbursts, and its relation to other wavelength data.

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내마모판의 광폭 경화육성 용접비드 형성을 위한 트윈토치 CMAW 공정개발 (Development of Twin Torch Compound Metal Arc Welding Process to Form for Wide Hardfacing Bead of Wearplate)

  • 조상명;김성덕;황규민
    • Journal of Welding and Joining
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    • 제26권2호
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    • pp.50-54
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    • 2008
  • The wearplate with Cr-C has been used in condition of severe abrasion. Recently, the demand of wearplate made by hardfacing with Cr-C has increased in the world, but it is lack of supply and expensive due to low productivity. CMAW (Compound Metal Arc Welding) is very useful process of several welding methods to make wearplate. In this paper, twin torch CMAW to use twin torch at the same time was developed to improve productivity and to ensure quality of wear plate. When the distance between two touches was smaller than 30mm, arc blow was occurred. However when the distance was larger than 35mm, there was no arc blow any more. If the oscillation path of each torch was overlapped together, the melt through at the overlapped zone was occurred due to concentrated heat input in substrate. On the other hand, the turning point of each torch was open more than 5mm, separated bead was generated. Therefore twin torch CMAW which has adequate conditions was able to make wearplate having flatter surface at the bead connection than single torch.

High redshift galaxy clusters in ELAIS-N1/N2 fields with a new color selection technique

  • Hyun, Minhee;Im, Myungshin;Kim, Jae-Woo;Lee, Seong-Kook
    • 천문학회보
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    • 제39권1호
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    • pp.48.1-48.1
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    • 2014
  • Galaxy clusters, the largest gravitationally bound systems, are an important means to place constraints on cosmological models. Moreover, they are excellent places to test galaxy evolution models in connection to the environments. To this day, massive clusters have been found unexpectedly(Kang & Im 2009, Durret et al. 2011, Tashikawa et al. 2012) and evolution of galaxies in cluster have been still controversial (Elbaz et al. 2007, Cooper et al. 2008, Tran et al. 2009). Finding galaxy cluster candidates at z>1 in a wide, deep imaging survey data will enable us to solve the such issues of modern extragalactic astronomy. We report new candidates of galaxy clusters and their physical properties in one of the wide and deep survey fields, European Large Area ISO Survey North1(ELAIS-N1) and North2(ELAIS-N2) fields, covering sky area of and each. We also suggest a new useful color selection technique to separate 1 < z < 2 galaxies from low-z galaxies by combining multi-wavelength data from the UKIRT Infrared Deep Sky Survey Deep Extragalactic Survey (UKIDSS DXS/J and K band), Spitzer Wise-area InfraRed Extragalactic survey (SWIRE/two mid-infrared bands), Canada France Hawaii Telescope (CFHT/z band), Issac Newton Telescope(INT/ u, g, r, i, z band) and Infrared Medium-deep Survey(IMS/J band).

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모먼트법을 이용한 스파이럴 안테나의 해석 및 설계 (Analysis and Design of a Spiral Antenna using Moment Method)

  • 한정세;이갑수;박병우
    • 한국통신학회논문지
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    • 제19권5호
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    • pp.857-871
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    • 1994
  • 본 논문에서는 스파이럴 암폭이 넓은 경우와 좁은 경우, 곡률이 큰 경우와 작은 경우에 대한 스파이럴 안테나를 모먼트법을 이용하여 해석하였다. 그 방법은 안테나를 N개 선소로 분할하고 갤러킨 방법을 이용하여 각 선소의 전류분포를 구하고, 방사패턴을 계산한 다음 이들을 실험 결과와 비교하였다. 안테나의 이득이 주파수에 따란 +_ 5dB 이내로 변화가 있는 것은 밸런과 안테나간의 접속에서 나타나는 반사손실에 의한 것이다. 시뮬레이션 및 실험결과를 통하여, 본 스파이럴 안테나의 광대역 무지향 특성을 확인하였다.

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Modified models predicting punching capacity of edge column-slab joints considering different codes

  • Hamdy A. Elgohary;Mohamed A. El Zareef
    • Structural Engineering and Mechanics
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    • 제89권4호
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    • pp.363-374
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    • 2024
  • Significant changes have been made to estimate the punching shear capacity for edge column-slab joints in the latest editions of most current codes. The revised equations account for axial forces as well as moments conveyed to columns from slabs, which have a substantial impact on the punching resistance of such joints. Many key design parameters, such as reinforcement-ratio, concrete strength, size-effect, and critical-section perimeter, were treated differently or even ignored in various code provisions. Consequently, wide ranges of predicted punching shear strength were detected by applying different code formulas. Therefore, it is essential to assess the various current Codes' design-equations. Because of the similarity in estimated outcomes, only the ACI, EC, and SNiP are used in this study to cover a wide range of estimation ranges from highly conservative to unconservative. This paper is devoted to analyzing the techniques in these code provisions, comparing the estimated punching resistance with available experimental data, and finally developing efficient models predicting the punching capacity of edge column-slab connections. 63 samples from past investigations were chosen for validation. To appropriately predict the punching shear, newly updated equations for ACI and SNiP are provided based on nonlinear regression analysis. The proposed equations'results match the experimental data quite well.

가상공간지도 기반의 3차원 가상공간 저작도구의 개발 (The Development of Authoring Tool for 3D Virtual Space Based on a Virtual Space Map)

  • 정일홍;김은지
    • 한국컴퓨터정보학회논문지
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    • 제11권2호
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    • pp.177-186
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    • 2006
  • 이 논문은 입력 영상에 대해 기존의 영상기반 렌더링 기법을 적용하고 가상공간지도라는 개념을 도입하여 사실적인 3차원 가상공간을 구축할 수 있는 효율적인 저작도구 개발에 대한 연구를 기술하고 있다. TIP 같은 기존의 기법들은 단일 영상을 사용하여 작은 3D가상공간을 구축하는 반면 여기서 제안하는 저작도구는 복수의 영상을 사용하여 광범위한 가상공간을 구축한다. 이 저작도구는 입력영상 각각에 대해 작은 3차원 가상공간을 구축하고 먼저 정의된 가상공간지도를 사용하여 이 독립적인 3D가상공간을 서로 연결하여 광범위한 3D가상공간을 구축할 수 있게 설계되었다. 가상공간지도는 세 가지 구성요소와 세 가지 방향으로 구성되어있다. 세 가지 구성요소는 특정 공간, 연결점 및 통로이고, 세 가지 방향은 정방향, 역방향 및 양방향이다. 가상공간지도는 가상공간의 연결구조, 네비게이션 정보 등 다양한 정보를 가지고 있다. 또한 이 저작도구는 사용자가 광범위한 3차원 가상공간을 쉽게 구축할 수 있게끔 사용자 인터페이스를 제공하고 있다.

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Mechanistic insight into the progressive retinal atrophy disease in dogs via pathway-based genome-wide association analysis

  • Sheet, Sunirmal;Krishnamoorthy, Srikanth;Park, Woncheoul;Lim, Dajeong;Park, Jong-Eun;Ko, Minjeong;Choi, Bong-Hwan
    • Journal of Animal Science and Technology
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    • 제62권6호
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    • pp.765-776
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    • 2020
  • The retinal degenerative disease, progressive retinal atrophy (PRA) is a major reason of vision impairment in canine population. Canine PRA signifies an inherently dissimilar category of retinal dystrophies which has solid resemblances to human retinis pigmentosa. Even though much is known about the biology of PRA, the knowledge about the intricate connection among genetic loci, genes and pathways associated to this disease in dogs are still remain unknown. Therefore, we have performed a genome wide association study (GWAS) to identify susceptibility single nucleotide polymorphisms (SNPs) of PRA. The GWAS was performed using a case-control based association analysis method on PRA dataset of 129 dogs and 135,553 markers. Further, the gene-set and pathway analysis were conducted in this study. A total of 1,114 markers associations with PRA trait at p < 0.01 were extracted and mapped to 640 unique genes, and then selected significant (p < 0.05) enriched 35 gene ontology (GO) terms and 5 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways contain these genes. In particular, apoptosis process, homophilic cell adhesion, calcium ion binding, and endoplasmic reticulum GO terms as well as pathways related to focal adhesion, cyclic guanosine monophosphate)-protein kinase G signaling, and axon guidance were more likely associated to the PRA disease in dogs. These data could provide new insight for further research on identification of potential genes and causative pathways for PRA in dogs.