• 제목/요약/키워드: set net

검색결과 823건 처리시간 0.023초

계류된 수중 유연구조물의 설계 및 시뮬레이션 도구 개발 (Design and Simulation Tools for Moored Underwater Flexible Structures)

  • 이춘우;이지훈;최무열;이건호
    • 한국수산과학회지
    • /
    • 제43권2호
    • /
    • pp.159-168
    • /
    • 2010
  • This paper presents a mathematical model and simulation method for investigating the performance of set net systems and fish cage systems influenced by currents and waves. Both systems consist of netting, mooring ropes, a floating collar and sinkers. The netting and ropes were considered flexible structures and the floating collar was considered an elastic structure. Both were modeled on a mass-spring model. The structures were divided into finite elements and mass points were placed at the mid-point of each element, and the mass points were connected by mass-less springs. Each mass point was subjected to external and internal forces and the total force was calculated at every integration step. An implicit integration scheme was used to solve the nonlinear dynamic system. The computation method was applied to dynamic simulation of actual systems simultaneously influenced by currents and waves in order to evaluate their practicality. The simulation results improved our understanding of the behavior of the structure and provided valuable information concerning the optimized design of set net and fish cage systems exposed to an open ocean environment.

기장 연안 정치망에 어획된 어류의 종조성 및 계절변동 (Species Composition and Seasonal Variations of Fishes Collected by Set Net in Coastal Waters of Gijang, Korea)

  • 이동진;강수경;최광호;정경미
    • 한국수산과학회지
    • /
    • 제47권6호
    • /
    • pp.983-996
    • /
    • 2014
  • Fish catches by a set net from January 2007 to November 2009 were analyzed to assess fish species composition and seasonal variations in the coast of Gijang, Korea. Over 389 kg fish representing 78 species, 45 families and 17 orders were collected during three years of the study. Dominant species were jack mackerel Trachurus japonicus, anchovy Engraulis japonicus and herring Clupea palasii, and these three species comprised 67.3% of the total number of individuals and 60.7% of the total biomass. Size distribution of the dominant species for jack mackerel, anchovy and herring ranged from 2.2 cm to 22.6 cm, from 2.5 cm to 14.8 cm, from 4.0 cm to 29.0 cm in fork length, respectively. Anchovy was the only species that occurred throughout all seasons in the Gijang coast. Generally, species richness was highest in spring (April to June) when sea temperature began to increase.

제주도 귀덕 연안에서 정치망에 의해 채집된 어획물의 종조성 및 어획량 변동 (Species composition and variation of catches by a set net in the coastal waters of Gyudeok, Jeju island)

  • 김맹진;이종희;이창헌;김병엽
    • 수산해양기술연구
    • /
    • 제50권3호
    • /
    • pp.407-415
    • /
    • 2014
  • Fish was caught by a set net in Gwideok, Jeju island that was studied to determine monthly variation of species composition and catch from May 2005 to October 2006. Total catch was 54 species, 44,118 individuals, and 2,152,423.7 g during survey period. Dominant species were Trachurus japonicus and Siganus fuscescens that held 91.3% of total individuals and 71.3% of total abundance. The highest individuals and abundance of catch were in July 2005, and the lowest individuals and abundance of catch were in October 2006 and in October 2005, respectively. As the result, temporal change in abundance have corresponded with changing water temperature.

통영 연안 정치망에 어획된 어류의 종조성 및 계절변동 (Species composition and seasonal variations of fishes collected by set net in coastal waters off Tongyeong, Korea)

  • 이용득;정재묵;김한주
    • 수산해양기술연구
    • /
    • 제59권1호
    • /
    • pp.9-18
    • /
    • 2023
  • Fish samples were collected by a set net from April to December 2020 at the coastal waters off Tongyeong, Korea to determine fish species composition and seasonal variation. A total of 330,675 fish (1,032,578 g) representing 56 species belonging to 39 families were collected during the sampling period. The dominant species were Engraulis japonicus, Trachurus japonicus and Trichiurus japonicus, which accounted for 98.1% of the total number of individuals and 87.5% of the total biomass collected. E. japonicus and Chelidonichthys spinosus appeared every month off the coast of the Tongyeong. Cluster analysis based on the number of individuals of fish were classified into two groups at the dissimilarity level of 57%, and the results of ANOSIM analysis revealed significant differences in community structure among the two groups.

ON THE C-NETS

  • Lee, Seung On;Pi, Young Jin;Oh, Ji Hyun
    • 충청수학회지
    • /
    • 제23권1호
    • /
    • pp.109-117
    • /
    • 2010
  • In this paper, we define the concept of a c-net and study the convergence of c-nets. Also we show that a c-net in a topological space X has a convergent sub-c-net if and only if X is a $Lindel{\ddot{o}}f$ space, if every $G_{\delta}$ set is open in X.

다중 컴퓨터 시스템에서의 Beta-network의 링크선에 관한 Fault-tolerance 분석 (Fault-tolerance Analysis of Link Line of Beta-network in the Multicomputer System)

  • 전우천;김성천
    • 대한전자공학회논문지
    • /
    • 제24권4호
    • /
    • pp.610-617
    • /
    • 1987
  • This thesis is concerned with fault-tolerance of a B-net (Beta-network) which is a kind of interconnection network in the multicomputer system. In this paper, a method for obtaining Maximal Tolerable Fault Set(MTFS) of link line connecting switching elements in the arbitrary B-net is presented. Using this method, it is seen that testing of DFA capability is possible when s-a-faults of link line occur, and criterion for determining degree of fault- tolerance of a B-net in terms of link line is introduced.

  • PDF

한국 남해안의 1개 단위인공어초의 적정 규모 (Optimum Size of a Reef Set in the Southern Water of Korea)

  • 김창길;김호상;서장우;정금철
    • 한국마린엔지니어링학회:학술대회논문집
    • /
    • 한국마린엔지니어링학회 2006년도 전기학술대회논문집
    • /
    • pp.193-194
    • /
    • 2006
  • This study describes the optimum size of a reef set in Korean coastal waters. Data were analyzed in relation to the weight and variety of fish species caught with a three-layer gill net. The results did not indicate a significant difference in the mean catch and mean number of fish species among the three different reef sets, 800, 1,600 and 2400 $m^3$.

  • PDF

Topology-Aware Fanout Set Division Scheme for QoS-Guaranteed Multicast Transmission

  • Kim, Kyungmin;Lee, Jaiyong
    • Journal of Communications and Networks
    • /
    • 제15권6호
    • /
    • pp.614-634
    • /
    • 2013
  • The proliferation of real-time multimedia services requires huge amounts of data transactions demanding strict quality-of-service (QoS) guarantees. Multicast transmission is a promising technique because of its efficient network resource utilization. However, high head-of-line (HOL) blocking probability and lack of service-specific QoS control should be addressed for practical implementations of multicast networks. In this paper, a topology aware fanout set division (TAFD) scheme is proposed to resolve these problems. The proposed scheme is composed of two techniques that reduce HOL blocking probability and expedite packet delivery for large-delay branches regarding multicast tree topology. Since management of global topology information is not necessary, scalability of the proposed scheme is guaranteed. Mathematical analysis investigates effects of the proposed scheme and derives optimal operational parameters. The evaluation results show that the TAFD scheme achieves significant delay reduction and satisfies required delay bounds on various multicast networks.

CNN을 이용한 안저 영상의 녹내장 검출 (Glaucoma Detection of Fundus Images Using Convolution Neural Network)

  • 신수연
    • 한국정보통신학회:학술대회논문집
    • /
    • 한국정보통신학회 2022년도 춘계학술대회
    • /
    • pp.636-638
    • /
    • 2022
  • 본 논문은 의료진단 검출 분야에서 혈관, 신경조직, 망막 손상 그리고 다양한 심혈관계 질환과 치매까지 진단하는 데 유용하게 사용하고 있는 안저 영상에 CNN(Convolution Neural Network) 알고리즘을 적용하고 녹내장 병변을 검출하기 위한 연구를 진행한다. 실험을 위하여 정상 안저 영상과 녹내장 병변이 있는 안저 영상으로 구성된 데이터 세트를 AlexNet으로 분류하고 그 성능을 확인하였다.

  • PDF