• Title/Summary/Keyword: 주기기

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동해안 참가자미, Limanda herzensteini의 생식주기

  • 장윤정;이정용;장영진
    • Proceedings of the Korean Aquaculture Society Conference
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    • 2003.10a
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    • pp.53-53
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    • 2003
  • 참가자미, Limanda herzensteini는 가자미목 (Pleuronectiformes), 가자미과 (Pleuronectidae)에 속하며, 우리나라의 동해, 일본의 세토내해 이북, 중국 및 사할린 근해에 분포하는 어종이다. 본 종은 연안정착성 어종으로 동해안에서 낚시 및 저인망 어업에 의해 어획되는 산업적 가치가 큰 고급어종이며, 저수온에 강하여 한류성 해역에서의 양식 가능성이 매우 높다고 할 수 있다. 또한 최근에는 참가자미의 자원량 감소가 두드러지고 있으므로 자원증강이 절실히 요구된다. 이 연구에서는 주 어획지역인 강원도 주문진 인근해역에서 1998년 9월부터 1999년 10월까지 자연산 참가자미의 연간 생식소중량지수의 변화를 조사 하였으며, 조직학적 조사에 의한 생식소 발달과정과 생식주기를 밝혔다. 정소는 정소엽 형태이며, 각각의 정소엽은 여러개의 소낭구조를 가진다. 각 소낭내의 생식세포들은 같은 단계의 발달상태를 보인다. 난소는 원추형의 낭상으로 체강벽에서 연결되는 난소간막에 의해 부착되어 있으며, 내부는 결체성 조직인 다수의 난소박판으로 구성되며, 이곳에서 난원세포가 유래한다. 수컷의 GSI는 1월에 가장 높았으며, 암컷의 GSI는 3월에 가장 높은 값을 보였다. 생식주기는 성장기(6~9월), 성숙기(10~12월), 완숙 및 산란기(1~3월) 그리고 회복 및 휴지기(4~5월)로 나눌 수 있었다. 난모세포의 발달양식은 난군동기발달형에 속하였다.

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Reproductive Cycle of Seabass, Lateolabrax japonicus (농어, Lateolabrax japonicus의 생식주기)

  • Kang, Duck-Young;Han, Hyoung-Kyun;An, Cheul-Min
    • Korean Journal of Ichthyology
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    • v.13 no.3
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    • pp.201-209
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    • 2001
  • Annual reproductive cycle of seabass, Lateolabrax japonicus, was histologically investigated based on samples captured on the coast of the Tongyoung, South Korea. The gonadosomatic index (GSI) of females began to increase in October and reached its maximum in February. The GSI of males reached its maximum in December. The change of GSI and gonadal tissue showed that the annual reproductive cycle was classified into the following successive four stages: (1) the degenerative and resting stage from March to August, (2) the growth stage from September to November, (3) the mature stage from November to December, and (4) the ripe and spawning stage from December to March.

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Variable Rate Limiter in Virus Throttling for Reducing Connection Delay (연결설정 지연 단축을 위한 바이러스 쓰로틀링의 가변 비율 제한기)

  • Shim, Jae-Hong
    • The KIPS Transactions:PartC
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    • v.13C no.5 s.108
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    • pp.559-566
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    • 2006
  • Virus throttling technique, one of many early worm detection techniques, detects the Internet worm propagation by limiting the connect requests within a certain ratio. The typical virus throttling detects worm occurrence by monitoring the length of delay queue with the fixed period of rate limiter. In this paper, we propose an algorithm that controls the period of rate limiter autonomically by utilizing the weighted average delay queue length and suggest various period determination policies that use the weighted average delay queue length as an input parameter. Through deep experiments, it is verified that the proposed technique is able to lessen inconvenience of users by reducing the connection delay time with haying just little effect on worm detection time.

Reproductive Cycle of the Brown sole, Limanda herzensteini in Eastern Waters of Korea (동해안 참가자미, Limanda herzensteini의 생식주기)

  • 장윤정;이정용;장영진
    • Journal of Aquaculture
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    • v.17 no.2
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    • pp.128-132
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    • 2004
  • Reproductive cycle of the brown sole, Limanda herzensteini was investigated by means of histological methods. The testis showed the presence of seminiferous tubule. The tubule consisted of many testicular cysts, each of which contained numerous germ cells - all at the same developmental stage. The ovary consisted of several ovarian lamellae and the oogonia originated from the inner surface of the ovarian lamella. Oocyte development was group-synchronous. Gonadosomatic index (GSI) of the male and female was the highest in January and March, respectively. Reproductive cycle could be classified into the growing (June-September), maturation (October-December), ripe and spent (January-March), and recovery and resting (April-May).

An Analysis of Engine Failures Using Multivariate Data Analysis Method (다변량해석법을 이용한 기관고장분석)

  • 윤석훈
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.23 no.4
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    • pp.198-203
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    • 1987
  • The basis of all approaches to improve reliability of marine engines exists in analyzing the field data of troubles and failures on marine engines. This paper analyses the data of troubles and failures on marine engines by Principal Component Analysis Method, one of Multivariate Data Analysis Method. The total number of data investigated is 211 and the observation period is 9 years. The analyzed factors are categorized among five groups respectively; electric.automatic control equipments, auxiliary machinery, pipings, refrigerators.air conditioners, and main engine. The failures in main engine are discovered by a definite fact of disorder, on the contrary, the failures in auxiliary machinery, refrigerators and air conditioners are discovered by sensible judgement of the operators.

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A Study on the Role of Web-Toon Agency from the View point of Industrial Life Cycle theory (산업수명주기론 관점으로 본 웹툰에이전시 역할에 관한 연구)

  • Kang, Eun-won
    • Cartoon and Animation Studies
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    • s.51
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    • pp.225-254
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    • 2018
  • For the domestic web-toon industry, a new industrial environment has been created by the growth various domestic and international factors, such as technology development, the increase of platforms, charged web-toon, and globalization. Although the role of the agency has not been emphasized at the formation and introduction time of the web-toon, the role growth of the agency has been regularized with the expanding of the web-toon industry. The expending web-toon industry is due to the introduction of smart-phone, by which people can consume the web-toon without any limit of time and place, so the web-toon industry has been growing rapidly. Thereafter the production of the second contents using the web-toon IP has been actively carried out and the activity area of the web-toon artist has been diversified, so the necessity of the specialized web-toon agency has begun to be brought in earnest. In this study, the web-toon industry has been, firstly, classified as transition period of cartoon industry, foothold formation period of web-toon, introduction period of web-toon industry, expansion period, and maturity period according to the industrial life cycle theory. As a result, the web-toon agency has been emerged from the expansion period of web-toon industry, and the role of agency, to prevent web-toon industry entering into declining period from its maturity period, has been researched in this study.

Magneto-inductive Wave in Periodic Chain of Ferrite Cores and Chip Capacitors (페라이트 코어와 칩캐패시터의 주기적 연결구조에서 발생하는 자기유도파)

  • Shin, Kwang-Ho
    • Journal of the Korean Magnetics Society
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    • v.25 no.1
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    • pp.22-26
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    • 2015
  • In this paper, a magneto-inductive wave generated in a chain of LC resonators fabricated with Ni-Zn ferrite cores and chip capacitors is presented. RF signal propagates to neighbor resonator one by one as a consequence of the magnetical coupling between two resonators in the device. The magnetical coupling is due to the mutual inductances along the chain of resonators. So, the signal amplitude (${\approx}$ coupling intensity) is dependent of the mutual inductance which can be adjusted by applied magnetic field. In order to demonstrate the device, some experiments have been carried out systemically. The transmission characteristics of a magneto-inductive wave could be controlled by applied external magnetic field. The device composed of 5 resonators; the center frequencies were estimated to be 32 MHz and 38 MHz with the external magnetic flux density of 75 Oe and 222 Oe, respectively. We expect that the reported results could open a promising way to a high variety of applications in one- and two-dimensional functional devices, such as transducers, delay lines, power dividers and couplers.

The T-tree index recovery for distributed main-memory database systems in ATM switching systems (ATM 교환기용 분산 주기억장치 상주 데이터베이스 시스템에서의 T-tree 색인 구조의 회복 기법)

  • 이승선;조완섭;윤용익
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.9
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    • pp.1867-1879
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    • 1997
  • DREAM-S is a distributed main-memory database system for the real-time processing of shared operational datra in ATM switching systems. DREAM-S has a client-server architecture in which only the server has the diskstorage, and provides the T-Tree index structure for efficient accesses to the data. We propose a recovery technique for the T-Tree index structre in DREAM-S. Although main-memory database system offer efficient access performance, the database int he main-memory may be broken when system failure such as database transaction failure or power failure occurs. Therfore, a recovery technique that recovers the database (including index structures) is essential for fault tolerant ATM switching systems. Proposed recovery technique relieves the bottleneck of the server processors disk operations by maintaining the T-Tree index structure only in the main-memory. In addition, fast recovery is guaranteed even in large number of client systems since the T-Tree index structure(s) in each system can be recovered cncurrently.

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