• 제목/요약/키워드: Variable Breadth

검색결과 18건 처리시간 0.019초

Some Aspects of Laying, Incubation and Hatching in the Great Reed-Warbler

  • Yoo, Jeong-Chil;Choi, Yu-Seong
    • The Korean Journal of Ecology
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    • 제25권4호
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    • pp.241-245
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    • 2002
  • During the breeding season of 1998, breeding ecology of the Great Reed-Warbler (Acrocephalus arundinaceus orientalis) was studied at Yangsoo-ri and Yongdam-ri of the Yangpyung-gun, Kyunggi province, Korea. Egg-weight (CV: 6.25) was more variable than either length or breadth, and breadth was the least variable of the measures. Significant variations in overall egg-weight occurred between clutches, and that more of the total variation in egg-weight and shape are due to inter-clutch variation as to intra-clutch variation when the data were pooled. The last egg tends to be larger than the remaining eggs in the clutch of the Great Reed-Warbler, suggesting the Great Reed-Warbler may adopt the brood-survival strategy. When method 3 was used, the most common incubation period is 12 days. In the Great Reed-Warbler, the length of the incubation period was related to clutch-size when method 1 (r=0.485, p<0.05) and method 2 (r=0.621, p<0.01) were employed, but not related to egg weight. The averagee number of days of hatching asynchrony was 2.5, raging 0.5~2.5. Asynchronous hatching was related to the clutch size (r=0.66, p<0.01). Hatching sequence was closely related to the laying sequence (r=0.93, p<0.001), suggesting Great Reed-Warblers incubate their eggs before clutch completion. The effect of egg weight on hatching asynchrony was found in Great Reed-Warblers (t-test, p<0.01).

서해안 송도매립지에서 번식하는 검은머리갈매기의 현황과 번식생태 (Breeding Status and Ecology of Saunders' Gulls (Larus saundersi) in Songdo Reclaimed Land, West Coast of Korea)

  • 권영수;정훈
    • Ocean and Polar Research
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    • 제31권3호
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    • pp.277-282
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    • 2009
  • Saunders' gulls (Laurs saundersi) which are listed as globally vulnerable species on the IUCN Red List are distributed in East Asia and breed mainly in China and Korea. Their population is estimated to be between 7,100 to 9,600. Songdo reclaimed lands in the western coast of South Korea are the main breeding sites for these species. However, most of these breeding sites have been seriously disturbed in the last several years because of new urban development constructions. This study was conducted to provide baseline data on the breeding ecology of Saunders' gulls. Since 1998, the breeding population has rapidly increased in South Korea, with the number of nests rising from 85 nests in 2000 to 185 nests in 2005. Egg volume is more variable than breadth or length. Clutch size, hatching and breeding success were $2.9{\pm}0.81$ (n=182, mean$\pm$sd.), 48.07% (75 hatched egg/156 eggs) and 29.08% (155 fledglings/533 eggs), respectively. Factors affecting breeding failure were predation, rainfall, starvation and supernormal clutches. These results are provided along with other cited literature to argue for conservation of Saunders' gulls.

중소유역의 수문학적 특성이 하천유사량에 미치는 영향 (The Effects of Hydrologic Characteristics on Sediment Discharge in Streams with Small and Medium Size Watersheds)

  • 김활곤;서승덕
    • 한국농공학회지
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    • 제38권3호
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    • pp.127-136
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    • 1996
  • The purpose of this study is to provide with information for the water resources development and management in stream management planning, such as information on the sediment trensport, design of dam and water facilities, river improvement and flood plains management. The major results obtained from the field measurement and analysis of the watershed characteristics, hydraulic and sediment characteristics are as follows ; 1. The rating curve formulas obtained from the analysis of the hydraulic characteristics data collected are ; Q-=110.563 $(H-0.474)^2$ for 0.7m$(H-0.146)^2$ for 0.4m$Sr=aX{^2} {_1} X^{c}{_2}$, in the experimental watershed.

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해양시스템 모형실험을 위한 수중운동계측시스템 개발 연구 (Development of Underwater Motion Measurement System for Model Test of Ocean System)

  • 최종수;홍섭
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2004년도 학술대회지
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    • pp.166-172
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    • 2004
  • An underwater motion measurement system was constructed for applications to the model basin. A commercial motion capture system, FALCON of Motion Analysis Corp., which corrects automatically the distortion caused by refraction of the light passing through water and air, was adopted for underwater motion measurement. The modifications of FALCON system were performed: waterproofing camera housings, markers, connectors, and a new blue ring lighter. the accuracy of the motion measurement was obtained within the calibration error of 0.87mm in average and 0.89mm in standard deviation for the distance of 500mm between two markers on the calibration device. the volume of $2100mm(length)\times2100mm(breadth)\times2300mm(Height)$ was covered with 4 cameras of the underwater motion measurement system. For the performance verification, motion measurement test of a vertical mooring chain model excited at the top end was carried out. The 3D motions of mooring model were measured with variable amplitude and period of the forced excitation. Higher order motions of the mooring model were observed as the excitation period decreases. the performance of the system was verified by successfully measuring 3D motion of mooring model.

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PHV 척도를 기준한 피하지방후, 근과 골 변인의 사춘기 발육분출에 관한 연구 (A Study on the Adolescent Growth Spurt of Skinfold, Muscle and Bone Variables Aligned on Peak Height Velocity in Boys and Girls)

  • 신상근
    • 생명과학회지
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    • 제16권2호
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    • pp.339-344
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    • 2006
  • 인간의 신체적 발육에 있어서 현저한 변화를 보이며, 다른 연령기에 비해 신체교육의 가능성이 크다고 인식되는 아동기와 사춘기 남 녀를 대상으로 생리학적 연령의 PHV 척도를 기준한 피하지방후, 근과 골 변인의 사춘기 발육분출 변화 양상을 분석 평가 하였다. 신장의 PHV 출현은 남자의 경우 $13{\sim}14$세 사이 이며, 여자는 2년 빠른 $11{\sim}12$세 사이인 것으로 나타났다. 체지방의 4개부위에 대한 피하지방후합은 남자의 경우 PHV 출현 -2년에 $8.9mm{\cdot}yr^{-1}$로, 여자는 PHV 출현 +2년에 $11.3mm{\cdot}yr^{-1}$로 PV에 각각 도달 하였으며, 남 녀 모두 사춘기발육분출 에서 증감의 변동이 많은 양상을 나타내었다. 상완골폭에 있어서 남자의 경우 PHV 출현 -3년과 +2년에 $0.6cm{\cdot}yr^{-1}$$0.5cm{\cdot}yr^{-1}$로 2번의 PV에 도달하는 bi-modal 현상을 보였고, 여자는 PHV 출현 -1년에 $0.3cm{\cdot}yr^{-1}$로 PV에 도달하였다. 대퇴골폭에 있어서 남자는 PHV 출현과 동일시점에 $0.4cm{\cdot}yr^{-1}$로, 여자는 PHV 출현 -2년에 $0.4cm{\cdot}yr^{-1}$로 각각 PV에 도달하였다. 근육의 상완이두근 최대위에 있어서 남자는 PHV 출현 +2년에 $2.6cm{\cdot}yr^{-1}$, 여자는 PHV 출현 +1년에 $1.0cm{\cdot}yr^{-1}$로 PV에 각각 도달 하였고, 하퇴위에 있어서 남자는 PHV 출현 +2년에 $1.9cm{\cdot}yr^{-1}$, 여자는 PHV 출현과 동일한 시점에 $1.6cm{\cdot}yr^{-1}$로 PV에 도달 하였다. 전체적으로 보아 PHV 척도를 기준으로한 피하지방후 발육의 경우, 남자는 PHV 출현 이전, 여자는 PHV 출현이후, 골의 발육은 남 녀 모두 PHV 출현 이전, 근육의 발육은 남 녀 모두 PHV출현 이후 PV에 각각 도달하는 양상을 보였다.

유수소통을 통한 태화강 적조해결 방안 연구 (A Study on Taehwa River Red Tide Solution through Stream Flow)

  • 조홍제;윤성규
    • 한국습지학회지
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    • 제13권2호
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    • pp.363-375
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    • 2011
  • 최근 하수관거 매설과 하수종말처리장 등의 건설로 인해 도시하천의 수질이 크게 개선되고 있으나, 하 폐수 처리시설의 부족으로 하천으로 유입되는 다양한 오염물질은 수중생태계 교란과 적조를 발생시키고 있다. 울산 태화강의 하류부는 하폭이 크고 하상경사가 매우 완만한 감조하천으로써 갈 저수기에는 유속이 매우 느리게 된다. 게다가 약 1.2km 떨어져 있는 2개 교량의 전면기초로 된 교각보호공으로 인해 흐름이 정체되고 오염물질이 퇴적되어, 수년전부터 발생하고 있는 태화강 적조의 원인이 되거나 적조를 활성화 시키고 있다. 본 연구에서는 RMA2모형을 이용하여 두 교량의 교각을 독립기초로 개선하고 흐름을 소통시킬 수 있는 통수단면을 확보했을 때, 수리학적으로 개선될 수 있는 유속과 유량의 변화폭을 모의하였다. 그 결과 유속은 최대 약 103%, 유량은 최대 61% 증가하는 것으로 나타났다. 이는 적조를 직접 소멸시킬 수는 없으나 적조발생을 억제하거나 감소시킬 수 있으며, 오염물질의 퇴적을 막아 적조발생 원인을 근원적으로 제어할 수 있는 것으로 판단된다.

상호작용적 작품에서 놀이속성: 모리스 베나윤(Maurice Benayoun)의 작품을 중심으로 (Attributes of "Play" in Interactive Art: Interpreting Maurice Benayoun's Artworks)

  • 박연숙
    • 미술이론과 현장
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    • 제15호
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    • pp.83-109
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    • 2013
  • The study mainly discusses appreciation of interactive art works seen from the perspective of play attributes that make spectators glimpse the truth of things. The general studies of interactivity, as one of remarkable features in contemporary art, are regarding the relation between the effects of digital media and interactivity as well as video games. From the preceding discussion, I analyze the effects of the appreciating interactive art works which are focused on new sensory systems, the methods to intuit the essence of the art works. Based on the concept, as I investigate the play attributes found in the interactive art works, this study gives attention to the possibility that if the spectators can reach the inherent aspects of interactive art works, while interacting them. Thus to discuss the properties of the play, this article studies play concept of Johan Huizinga(1872-1945), psychologist and anthropologist and play theory of Hans Georg Gadamer(1900-2002) who considers play as a metaphor for art. As Huizinga thinks acting is the important attribute of play, Gadamer argues whenever the term 'play' is used, we should think about 'to-and tro movement' and the movement is absence of goal as well as endlessly renews through repetition. Then what we should pay attention to, seeing the essence of art and play as similar? That is, Gadamer claims, we can understand the truth of things through the play. To apply the play concept to the interactive art works, I research the works of Maurice Benayoun(1957 - ), French interactive artist. By employing interactivity, he attempts to extend and affect the experience of his art works to one of social phenomenon. Striving this, spectators can widen and deepen the breadth of their intuition and recognize the essence of art works. It is the interactive art works that can be the apex of the transformation of structure from the play to the art. The endless repetitive process of play, which is free creation-annihilation process, is similar with the interactive experience of spectators that is variable, de-centered, and multi-sensory. The pure action of the play lets us recognize, sense and accept the world and through the system of interactive art experience, we can expand the horizons of perception. Interactive art works with these play attributes are capable of playing the role that the spectators glimpse the truth of things and experience the world around them.

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제주 북동부 지역의 지형과 대기변수에 따른 AEP계산의 정확성에 대한 연구 (An Accuracy Estimation of AEP Based on Geographic Characteristics and Atmospheric Variations in Northern East Region of Jeju Island)

  • 고정우;이병걸
    • 한국측량학회지
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    • 제30권3호
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    • pp.295-303
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    • 2012
  • 풍력발전 단지의 수익성 평가를 위해 연간 에너지 생산량(AEP ; Annual Energy Production)의 계산이 중요하다. AEP를 계산하기 위해서는 바람의 확률밀도함수(PDF ; Probability Density Function)와 풍력발전기의 발전곡선(PC; Power Curve)이 필요하며, AEP 예측의 정확성을 향상시키기 위해서는 허브 높이에서의 PDF예측과 그 높이의 공기밀도에 따른 풍력발전기 PC의 결정이 중요하다. 본 연구에서는 제주도 한동, 평대의 실관측 풍황탑(met mast) 자료를 이용하였으며 풍속의 PDF를 Weibull 분포 함수로 가정 하였고 Weibull 함수의 파라미터의 값이 높이에 따라 변화하는 양상을 확인하였다. Weibul 함수의 계산은 모멘트법과 LN-least법을 사용하였으며, 모멘트법과 LN-least법에 의한 형상계수의 경우 높이의 증가에 따라 변화를 보이지 않았고 평균값에서 ${\pm}0.1$의 변화 패턴을 보였다. 척도계수의 경우 높이가 증가함에 따라 선형적으로 증가하였으며 지형별 분류에 따른 높이별 척도계수의 기울기는 확연한 차이를 보이고 있었다. 60m 높이에서 관측된 바람의 상대도수와 관측 값의 높이 보정에 의한 공기밀도와 일반식에 의한 공기밀도를 각각 계산하여 그 결과에 대응하는PC를 선택하여 AEP차이를 계산하였다.