• 한국수산과학회지
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• 제50권5호
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• pp.553-560
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• 2017

Fluctuations in the abundance and species composition of fishes in the coastal waters of Geumo-do, Yeosu, Jeollanam-do, Korea were investigated from 2002 to 2005. A gill net with entrances on both sides was used to collect a total of 469 individuals (55,180 g) of 3 orders, 18 families, and 28 species. The dominant species was Sebastes inermis (60 individuals, 5,670 g), followed by Neoditrema ransonneti (46 individuals, 2,290 g), and Pseudaesopia japonica (38 individuals, 3,080 g). The highest number of individuals was found in 2004, while the biomass was highest in 2005. The diversity index was highest in 2004 (H'=2.703) and lowest in 2002 (H'=2.580). The dominance index was highest in 2004 (D=3.983) and lowest in 2002 (D=3.404). The richness index was highest in 2003 (RI=0.337) and lowest in 2002 (RI=0.261). Changes in temperature and salinity affected the community structure and the location of spawning grounds. The number of individuals and total biomass increased with changes in temperature and salinity each year.

• 한국수산과학회지
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• 제50권3호
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• pp.296-301
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• 2017

We conducted a study to 1) determine the indicators of gonadal maturity in male and female Korean walleye pollock Theragra chalcogramma for the purposes of artificial insemination; 2) establish the RNA/DNA ratio of mature eggs in this species; and 3) monitor the effect of refrigerated storage on egg viability and the motility of sperm collected from dead adult males. During the spawning season, the color of female gonads changed from orange to transparent, and that of male gonads changed from pale orange to milky white. The DNA content and RNA/DNA ratio of mature eggs were maintained without significant changes for approximately 6 h when eggs were preserved at $4^{\circ}C$. Sperm could be obtained from both milt and undiluted semen. Sperm obtained from milt ceased moving on the second day after isolation, while over 60% of sperm obtained from semen showed movement until the 13th day. Seven attempts were made to artificially inseminate mature eggs, of which two resulted in successful fertilization. The successful inseminations produced 94,000 and 5,000 fertilized eggs, respectively. This study shows that artificial insemination of walleye pollock is a viable strategy when natural propagation is not possible.

• 한국패류학회지
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• 제28권3호
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• pp.255-258
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• 2012

표본은 2012년 3월 경상북도 독도주변해역에서 자망에 의해 어획된 것이다. 화살꼴뚜기는 몸통길이 (ML) 22.5-34.2cm (평균 $27.1cm{\pm}2.8$) 이다. 지느러미길이 (FL) 는 몸통길이 (ML) 의 2/3정도인 60%를 차지하였다. 지느러미폭(FW) 은 몸통길이 (ML) 의 약 1/2정도이다. 팔은 몸통길이(ML) 에 비해 짧고 굵으며, 팔길이식은 III>II>IV>I 이었다. 왼쪽 4번째 팔의 말단부 약 30%가 교접기로 되어 있다. 교접기는 아주 작은 흡반 및 거의 흔적적인 흡반이 나열되어있다. 표본 44개체 중 암컷 (♀) 은 23개체, 수컷 (♂) 21개체이었다. 생식소 발달단계는 암컷 (♀) 완숙단계, 수컷 (♂) 방정단계였다.

• 한국어류학회지
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• 제23권4호
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• pp.310-313
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• 2011

퉁돔과에 속하는 Aprion virescens 1개체(표준체장 151.4 mm)가 제주연안에서 자망으로 처음 채집되었다. 이 종은 눈 앞에 세로로 깊게 파인 홈이 있고, 가슴지느러미는 매우 짧아 주둥이 길이와 비슷하며 등지느러미에 선명한 4개의 점이 존재한다. 이 미기록종의 속명과 국명은 "녹색퉁돔속", "녹색퉁돔" 이라고 각각 제안하였다.

• 한국어류학회지
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• 제27권3호
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• pp.249-252
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• 2015

농어목 청줄돔과에 속하는 Chaetodontoplus melanosoma 1개체 (표준 체장 123.1 mm)가 2010년 2월 24일 제주도 사계연안의 삼중자망에서 처음으로 채집되었다. 이 종은 체측에 파란색 줄무늬가 없는 대신 멜라닌 색소가 잘 발달되어 있는 점, 눈 뒤에 반점이 없는 점, 그리고 가슴지느러미 기부에 검은색 반점을 가지는 점이 특징이다. 하지만, 청줄돔이 가지는 체측의 파란줄무늬가 이 종의 등지느러미에 희미하게 남아있으며 형태적으로도 유사하기 때문에 이 미기록종의 국명을 "검은청줄돔"으로 제안한다.

• 디지털산업정보학회논문지
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• 제12권4호
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• pp.89-96
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• 2016

Before an IT product is used, there is a sequence of the process such as the components supply-demand of the product, their assembly and production, their logistics and delivery, and then finally, the product can be used by a user. During this sequence of the process, there can be many security exposures and risks. In this paper, we show, by examining security cases of various IT products, that there are many security exposures in the process of IT products from their production to their delivery to end users and in their use, and also show how critical the security exposures are. Even though there are various security theories, technologies and security controls, there is still weak link from the production of an IT product to its use, and this weak link can lead to security vulnerabilities and risks. This paper tries to call attention to the importance of the execution of the security control and the control components. We examine the practical cases to find out how the security control is paralyzed, and to show how it is compromised by asymmetric security resources. Lastly, from the cases, we examine and review the possible domestic security issues and their countermeasures.

• 수산해양기술연구
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• 제49권1호
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• pp.1-17
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• 2013

The investigation for species composition and catch in the Korean deep-water of the East Sea (also known as Sea of Japan) was carried out with trammel nets of 7 mesh sizes (6.1~24.2cm) offshore Donghae (2006) and Yangyang (2007) of Korea. The catches were 1,268kg and composed of 37 species between 200m and 1,200m in depth. The principal species caught were Taknka's snailfish, salmon snailfish, red snow crab, hunchback sculpin, snow crab, spinyhead sculpin, Tanaka's eelpout, Alaska cod and so on. Those were target fish for commercial value except salmon snailfish. The mesh sizes for the largest catch were 10.6cm and 15.2cm in the fishing ground of Donghae and Yangyang, respectively. The habitat of snow crab was shallower than that of red snow crab in both areas. Trammel net enabled to investigate fish in deep-water with small fishing vessel and rather cheap expenses in contrast to bottom trawl that required too much of it. With increasing inner mesh size of trammel net the mean size of some principal species such as Taknka's snailfish, spinyhead sculpin, hunchback sculpin, Pacific cod, snow crab, red snow crab and hybrid between snow crab and red snow crab tended to be large in certain range of mesh size.

• 수산해양기술연구
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• 제53권4호
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• pp.317-326
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• 2017

Comparative fishing experiments were conducted in the eastern coastal waters near Uljin, Korea from 2002 to 2004, using the experimental trammel nets to estimate the selectivity for spinyhead sculpin Dasycottus setiger. The inner panels of the nets were made of nylon monofilament with four mesh sizes (82.2, 89.4, 104.8, and 120.2 mm) while its two outer panels were made of twisted nylon multifilament with a mesh size of 510 mm. The SELECT (Share Each Length's Catch Total) procedure with maximum likelihood method was applied to obtain a master selection curve. The different functional models (normal, lognormal, bi-normal, and logistic model) were fitted to the catch data. The lognormal model with the fixed relative fishing intensity was chosen as the best-fitted selection curve through comparison of model deviance and AIC (Akaike's Information Criterion). The optimum relative length (the ratio of fish total length to mesh size) with the maximum relative efficiency was obtained as 2.492.

• 수산해양기술연구
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• 제48권4호
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• pp.301-309
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• 2012

A net-assembling company for gill net fishing gears makes a design based on the size of nets provided and determines floats, types of weights, and numbers. In addition, through the accurate examination of net weights in the process of fishing gear designing, it can prevent an excessive use of designing costs. The weight of twine can be easily calculated by its thickness differences, but the weight of netting has errors to be calibrated since the weight of netting is not changing exponentially with the changes of number and size of meshes. This study aims to suggest and empirically analyze the methods for estimating the weights of netting in accordance with the changes of number, size and thickness of meshes for a sound management of netting and net-assembling companies. Results indicated that the method using the knots and legs of netting was not practically usable because the errors were increased as the number of mesh increased. However, the method using netting area shown its usage potentiality with the calibration of the increasing ratio of mesh numbers.

• 수산해양기술연구
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• 제46권3호
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• pp.223-231
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• 2010

This paper showed the difference between the selectivity of gill net by least square method with polynomials in Kitahara's and that by maximum likelihood analysis for Japanese sandfish and Korean flounder. Catch experiments for Japanese sandfish using commercial vessels off the eastern coast of Korea were conducted with six different mesh sizes between October and December 2007 and those for Korean flounder with five different mesh sizes between 2008 and 2009. The mesh size of 50% probability of catch corresponding to biological maturity length of fish was not different between that by least square method and that by maximum likelihood analysis for Japanese sandfish, however, a little different for Korean flounder, that is, those mesh sizes of 50% probability of catch for biological maturity length of Korean flounder were 10.6cm and 10.1cm by least square method and maximum likelihood analysis, respectively.