• 제목/요약/키워드: ISL

검색결과 78건 처리시간 0.026초

OFDM MIMO radar waveform design for targets identification

  • Bai, Ting;Zheng, Nae;Chen, Song
    • ETRI Journal
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    • 제40권5호
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    • pp.592-603
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    • 2018
  • In order to obtain better target identification performance, an efficient waveform design method with high range resolution and low sidelobe level for orthogonal frequency division multiplexing (OFDM) multiple-input multiple-output (MIMO) radar is proposed in this paper. First, the wideband CP-based OFDM signal is transmitted on each antenna to guarantee large bandwidth and high range resolution. Next, a complex orthogonal design (COD) is utilized to achieve code domain orthogonality among antennas, so that the spatial diversity can be obtained in MIMO radar, and only the range sidelobe on the first antenna needs suppressing. Furthermore, sidelobe suppression is expressed as an optimization problem. The integrated sidelobe level (ISL) is adopted to construct the objective function, which is solved using the Broyden-Fletcher-Goldfarb-Shanno (BFGS) algorithm. The numerical results demonstrate the superiority in performance (high resolution, strict orthogonality, and low sidelobe level) of the proposed method compared to existing algorithms.

거제도산 육서빈모류의 분류학적 연구 (On a Small Collection of Earthworms from Geo-Je Isl., Korea)

  • Song, Min-Ja;Paik, kap-Yong
    • 한국동물학회지
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    • 제13권4호
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    • pp.101-111
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    • 1970
  • 저자들은 1970년 8월에 채집된 거제도산 지렁이 총 251 개체를 정리한 결과 다음 2과 2속 9종을 얻었다. Pheretima acincta, Ph. agrestis, Ph. geojeinsulae n. sp., Ph. gucheonensis n. sp., Ph. heteropoda, Ph. hilgendorfi, Ph. koreana and Ph. soulensis; Allolobophora caliginosa trapezoides. 거제도의 지렁이에 관해서는 지금까지 보고된 바 없으므로 이들은 전부 거제도 미기록종이되며 이들 중에는 한국 미기리록종 Ph. acincta(Goto et Hatai, 1899)와 두개의 신종, Ph. geojeinsulae, Ph. gucheonensis를 포함하고 있다. Ph. geojeinsulae는 체장 185-210mm, 체폭 10-12mm, 체절수 125-136개, spermathecal pore는 2雙으로서 5/6 및 6/7에 있다. 본 종은 spermathecal pore region과 male pore region의 모양으로 이 속의 다른 종과는 뚜렷이 구별된다. 또 Ph. gucheonensis는 일본산의 Ph. tappensis Ohfuchi, 1935와 비슷하나 체장이 짧으며 (70:100), 특히 내부의 spermatheca의 모양이 전혀 다를 뿐 아니라 10/11, 11/12의 septa가 있는 점으로 뚜렷이 구별된다.

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분할등화기를 이용한 개선된 비적적응필터 (Improved Multiplication Free Adaptive Digital Filter with the Fractionally-Spaced Equalizer)

  • Yoon, Dal-Hwan
    • 대한전자공학회논문지SP
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    • 제39권2호
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    • pp.137-146
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    • 2002
  • 데이터 전송채널에서 부호간간섭(ISI)을 제거하기 위해 개선된 비적적응 디지털필터(IMADF)의 구조와 수렴해석이 이루어진다. 0평균, 백색잠음하에서 분할등화기(FSE)를 이용한 IMADF의 수렴특성을 해석한다. 실험결과 IMADF 알고리즘의 수렴독성이 Sign 알고리즘과는 같으나, MADF 알고리즘 보다 우수하다. 특히 입력신호의 상관관계가 높을 때 유용한 특성을 갖는다.

Ulleung-do earthworms - Dagelet Island revisited

  • Blakemore, Robert J.
    • Journal of Species Research
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    • 제2권1호
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    • pp.55-68
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    • 2013
  • Previous surveys on Ulleung-do (Dagelet Isl.) found just ten earthworm taxa while the current survey unearthed a dozen species. Placement of parthenogenetic 'tube' Amynthas dageletensis Hong & Kim, 2005 is resolved as it clearly belongs in synonymy of Metaphire soulensis (Kobayashi, 1938) which becomes a new Ulleung-do record. Other new megascolecids are recorded since Amynthas heteropodus (Goto & Hatai, 1898) and A. baemsagolensis Hong & James, 2001 are confirmed as synonyms of A. corticis (Kinberg, 1867) and A. carnosus (Goto & Hatai, 1899), respectively. The latter taxon is differentiated and its synonym A. pingi (Stephenson, 1925) provisionally revived. New lumbricids are Bimastos parvus (Eisen, 1874), Eisenia japonica (Michaelsen, 1892) and questionably Dendrodrilus rubidus (Savigny, 1826). All confirmed species are common exotics with no endemics. Drawida moniligastrids were not yet located on this remote island for reasons unknown.

램 가속기 탄체 형상에 따른 데토네이션파와 가속 특성에 관한 연구

  • 전용희;이재우;변영환
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 1999년도 제12회 학술강연회논문집
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    • pp.16-16
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    • 1999
  • 램 가속기 탄체 형상에 따른 가속 특성에 대한 연구는 열적 질식 모드에 대하여 Washington 대학, ISL 연구소 등에서 실험적으로 수행되어 졌으나 초폭굉 연소 모드에 대해서는 아직 미비한 실정이다. 초폭굉 연소 모드 램 가속기의 기본적인 탄체 형상은 원추-원통-원추로 이루어진 형상으로 탄체 전면에 형성된 경사 충격파가 탄체와 가속기 사이에서 반사되며 데토네이션파를 발생시켜 가속하게 된다. 탄체의 형상에 따라서 탄체 주위에 형성되는 충격파 구조는 차이를 나타내게 되고 발생되는 데토네이션파의 위치와 강도를 따라서 탄체의 가속특성은 상당한 차이를 나타낸다. 기본적으로 탄 체의 전면 형상은 경사 충격파의 강도와 단체 주위의 유동장의 특성을 결정하는 주요 요인이고 이에 따라 데토네이션파의 형성과 안정화 역시 결정되어 탄체의 가속 특성을 결정짓는다. 또한 데토네이션파를 임의의 위치에 형성하기 위해 이중 원추형상의 충격파-충격파 상호작용을 이용하여 데토네이션파를 발생시켜 탄체를 가속시킨다.

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Numerical Study on Propulsion Performance Enhancement of Superdetonative mode Ram Accelerator by using strong mixture

  • Sung, Kun-Min;Jeung, In-Seuck
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2008년 영문 학술대회
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    • pp.519-524
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    • 2008
  • A numerical study is conducted to investigate propulsion performance enhancement based on S225 experiment case of ISL(French-German Research Institute of Saint-Louis)'s superdetonative ram accelerator. For govern equation, multi-species Navier-Stokes equation coupled with Baldwin-Lomax turbulence modeling is used. Govern equation is discretized by Roe's FDS and integrated by LU-SGS time integration. Detailed chemical reaction about $H_2/O_2/CO_2$ for high pressure is considered. $2H_2+O_2+2.5CO_2$ mixture was used for propellant gas. For the same over-driven factor, the launching speed of computation was faster than one of S225. Another configuration and condition of S225 was applied. A flame structure is very different from S225. For strong mixture case, it shows ignition by viscous effect. Acceleration and speed increment is higher than S225 computation and experiment. By using more strong mixture, propulsion performance was enhanced.

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Lectotypification of Anaphalis morii Nakai (Asteraceae) with Brief Discussions of its Taxonomic Entity

  • Dong Hyuk Lee;Jun Gi Byeon;Tae Im Heo;Byeong Joo Park;Ji Dong Kim;Jun Woo Lee;Byeong Kwon Lee;Byeong-Hee Choi
    • 한국자원식물학회:학술대회논문집
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    • 한국자원식물학회 2020년도 춘계학술대회
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    • pp.16-16
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    • 2020
  • Systematic studies for genus Anaphalis in Koreaare relatively scarce. As a fundamental step to further taxonomic studies of this genus, we here propose lectotype for A. morii, endemic taxa in Korea with a brief re-evaluation of its taxonomic entity. During the examination of herbarium specimen for A. morii, we found nine sheets of five collections in three herbaria. Among the original materials, we selected a specimen in TI which was first cited by the author and include an additional annotation, matching with his own description. Also, we were able to determine the taxonomic relationships between A. morii and its relatives, A. yakusimensis. Based on our observation, we identified that several morphological characters are clearly differ from A. yakusimensis occurring only Isl. Yakushima in Japan.

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Dynamic Caching Routing Strategy for LEO Satellite Nodes Based on Gradient Boosting Regression Tree

  • Yang Yang;Shengbo Hu;Guiju Lu
    • Journal of Information Processing Systems
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    • 제20권1호
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    • pp.131-147
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    • 2024
  • A routing strategy based on traffic prediction and dynamic cache allocation for satellite nodes is proposed to address the issues of high propagation delay and overall delay of inter-satellite and satellite-to-ground links in low Earth orbit (LEO) satellite systems. The spatial and temporal correlations of satellite network traffic were analyzed, and the relevant traffic through the target satellite was extracted as raw input for traffic prediction. An improved gradient boosting regression tree algorithm was used for traffic prediction. Based on the traffic prediction results, a dynamic cache allocation routing strategy is proposed. The satellite nodes periodically monitor the traffic load on inter-satellite links (ISLs) and dynamically allocate cache resources for each ISL with neighboring nodes. Simulation results demonstrate that the proposed routing strategy effectively reduces packet loss rate and average end-to-end delay and improves the distribution of services across the entire network.

길상산 (강화도)의 관속식물상 (The Vascular Plants in Mt. Gilsangsan (Ganghwa-Isl.), Korea)

  • 김중현;김선유
    • 한국환경생태학회지
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    • 제27권3호
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    • pp.280-304
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    • 2013
  • 본 연구는 길상산의 관속식물상을 밝히고 주요 식물을 조사하였다. 2012년 3월부터 11월까지 총 14회에 걸쳐 수행되었다. 그 결과 관속식물은 122과 359속 529종 7아종 51변종 2품종 3교잡종으로 총 595분류군이 확인되었다. 길상산은 식물구계학상 온대중부지역에 속하고 낙엽활엽수와 침엽수의 혼합림으로 산지의 대부분은 소나무-참나무류림이 우점하며 2차림으로 구성된다. 종 다양성이 높은 과는 국화과(11.0%), 화본과(10.7%), 사초과(6.38%), 콩과(3.86%), 장미과(3.52%)였다. 한국 고유종은 각시족도리풀, 외대으아리, 고광나무, 개나리, 늦둥굴레 등 12분류군이 확인되었다. IUCN 평가기준에 따른 적색목록의 관속식물은 위기종(EN)인 구상나무, 준위협종(NT)은 산닥나무, 흑삼릉, 관심대상종(LC)에 측백나무, 개쓴풀, 금붓꽃, 미평가종(NE)으로 늦둥굴레가 조사되었다. 식물구계학적 특정식물종은 V등급, VI등급이 각각 2분류군, III등급 9분류군, II등급 3분류군, I등급 29분류군 등 45분류군이 발견되었다. 귀화식물은 64분류군으로 확인되었으며, 귀화율은 10.7%로 나타났다. 생태계교란 야생식물에는 애기수영, 가시박, 도깨비가지, 돼지풀, 단풍돼지풀, 미국쑥부쟁이, 서양금혼초, 가시상추 등 8분류군이었다. 또한 생활형조성은 일년생식물(26.5%), 반지중식물(26.0%), 지중식물(14.0%) 등이 높게 나타났다.

The Quality of Life after Lymphaticovenous Anastomosis in 118 Lower Limb Lymphedema Patients

  • Jin Geun Kwon;Yeongsong Kim;Min Young Jang;Hyunsuk Peter Suh;Changsik John Pak;Vaughan Keeley;Jae Yong Jeon;Joon Pio Hong
    • Archives of Plastic Surgery
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    • 제50권5호
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    • pp.514-522
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    • 2023
  • Background This is a prospective study on 118 patients who underwent lymphaticovenous anastomosis (LVA) due to secondary lower limb lymphedema between January 2018 and October 2020 to evaluate patients' quality of life (QOL) using the Quality of Life Measure for Limb Lymphedema (LYMQoL) questionnaire. Methods The outcome measurement included the LYMQoL leg scoring system tool evaluating the function, appearance, symptom, mood, and overall outcome. In addition, correlation analysis was performed for three factors: based on International Society of Lymphology (ISL) stages, disease duration, and amount of volume reduction. Results The LYMQoL tool overall satisfaction score significantly increased at all intervals from 4.4 ± 0.2 preoperative to 6.5 ± 0.3 postoperative at 12 months (p < 0.001). Significant findings were seen for each domain scores compared preoperatively and at 12 months: function score (18.6 ± 0.5 to 15.4 ± 0.6), appearance score (17.8 ± 0.5 to 16.0 ± 0.6), symptom score (11.8 ± 0.3 to 8.9 ± 0.4), and mood score (14.5 ± 0.4 to 11.4 ± 0.5; p < 0.05). The correlation analysis between improvement of the overall score and the ISL stage (p = 0.610, correlation coefficient [r] = -0.047), disease duration (p = 0.659, r = -0.041), and amount of limb volume reduction (p = 0.454, r = -0.070) showed no statistical significance. Conclusion The QOL of secondary lower limb lymphedema patients was significantly improved after LVA regardless of the severity of disease, duration of disease, and amount of volume reduction after LVA. Understanding the patient-reported outcome measurement will help the surgeons to manage and guide the expectations of the patients.