• 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.

• 수산해양기술연구
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• 제57권3호
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• pp.185-193
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• 2021

This study was conducted to evaluate the performance of the octopus pot according to mesh sizes. Entering behavior of Octopus minor and bait (Macrophthalmus japonicus) escape rate on the mesh sizes of the pots were investigated for six times in indoor tank. The sea trials for evaluating the performance of Octopus minor pot to different mesh sizes (22, 20 and 18 mm) were conducted for six times from 2017 to 2018 in the coastal sea of Deukyang Bay, the Republic of Korea. Behavior patterns of contact pot to leaved pot were more frequent than contact pot to bait search. When the octopus contacted to the pot, there was no clear search behavior to distinguish the mesh sizes. Total catch of 46% was accounted for 18 mm pots, followed by 34% at 20 mm and 20% at 22 mm (P < 0.05). Catch per unit effort was calculated as 30 g/pot at 22 mm, 44 g/pot at 20 mm and 59 g/pot at 18 mm. As a result of evaluating 50% selection of mantle length and weight on the mesh sizes, mantle length (mm) and weight (g) were 84.6 and 147.8 in 22 mm, followed by 20 and 18 mm.

• Structural Engineering and Mechanics
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• 제55권1호
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• pp.93-109
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• 2015

Finite element analysis (FEA) combined with the concepts of linear elastic fracture mechanics (LEFM) provides a practical and convenient means to study the fracture and crack growth of materials. In this paper, a numerical modeling of crack propagation in the cement mantle of the reconstructed acetabulum is presented. This work is based on the implementation of the displacement extrapolation method (DEM) and the strain energy density (SED) theory in a finite element code. At each crack increment length, the kinking angle is evaluated as a function of stress intensity factors (SIFs). In this paper, we analyzed the mechanical behavior of cracks initiated in the cement mantle by evaluating the SIFs. The effect of the defect on the crack propagation path was highlighted.

• 한국패류학회지
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• 제25권2호
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• pp.173-178
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• 2009

2006년 6월부터 11월까지 매월 1회씩 제주도 귀덕, 신산, 김녕, 강정 연안에서 정치망에 의해 채집된 흰꼴뚜기를 대상으로 흰꼴뚜기의 생식생물학적 특성에 관하여 연구하였다. 조사기간 동안 총 97 개체의 창꼴뚜기 중에서 암컷은 55 개체, 수컷은 42 개체로 나타났다. 암컷의 경우, 조사 기간 중 미숙, 중숙, 성숙, 완숙기의 개체들이 혼재하여 출현하였으며 산란이 가능한 완숙 개체는 조사 전 기간에 걸쳐 관찰되었고, 7월과 8월에 출현비율이 가장 높았다. 수컷도 조사기간 중 미숙, 중숙, 성숙, 완숙기의 개체들이 혼재하여 출현하였으며 생식소의 숙도가 방정이 가능한 성숙단계 이상의 개체는 전 기간에 걸쳐 관찰되었고 완숙기의 개체는 9월에 출현비율이 가장 높았으며 그 결과, 산란기는 7월이라 판단된다. 흰꼴뚜기가 산란에 참여하는 군성숙외투장을 알아본 결과 암컷은 20.5 cm, 수컷은 12.3 cm로 추정되었다.

• 한국해양학회지:바다
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• 제18권3호
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• pp.131-141
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• 2013

본 연구는 2011년 9월에서 12월까지 동해(북부, 중부, 남부), 서해, 동중국해의 해구에서 각각 채집된 살오징어의 계군을 형태 및 유전학 차이를 이용하여 구분하였다. 형태학적 차이에 따른 계군분석은 평균성숙외투장(20-22 cm)을 기준으로 하여 발생시기를 구분하였고, 유전학적 특성에 따른 계군은 mtDNA COI 영역의 염기변이에 의한 유전자 다양성을 이용하여 확인하였다. 본 연구 결과 평균성숙외투장을 기준으로 동해 북부는 발생시기가 하계군, 나머지 집단(동해 중부, 동해 남부, 동중국해 북부, 서해 북부)은 추계군으로 크게 2개의 계군으로 추정되었다. 유전자 분석결과 살오징어 mtDNA COI 영역에서 총 49개의 haplotype을 확인하였다. TCS 분석결과 haplotype 유전자형 네트워크가 star-like형태이며, 모든 집단에서 유전적 다양성(haplotype diversity, h)이 높고(h=0.661~0.841), 반면에 염기 다양도(nucleotide diversity, ${\pi}$)가 낮게 나타난 점으로 미루어보아 국내 서식 살오징어의 경우 최근에 급속한 집단의 분화가 이루어진 것으로 판단된다. Pairwise Fst를 이용한 집단분석결과 비록 모든 집단간의 유전적 차이가 낮게 나타났지만(Fst = 0.001~0.043) 평균성숙외투장 기준으로 같은 추계군으로 분류된 집단(동해 중부, 동해남부, 서해 북부)간에는 유전적 차이를 확인할 수 있었다(P<0.05).

• 한국수산과학회지
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• 제43권3호
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• pp.270-276
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• 2010

This study estimated the heavy metal concentrations in octopus (Octopus minor) and conducted a food safety assessment of octopus. Octopus, a benthic cephalopod, was collected from the Seosan intertidal zone on the west coast of Korea. The samples were digested with acids, and then the cadmium (Cd), copper (Cu), and zinc (Zn) contents were analyzed using inductively coupled plasma mass spectrometry (ICP-MS). The Cd, Cu, and Zn range of concentrations in octopus were 0.06-19 (mean 5.8), 44-1,463 (mean 354.8), and 76-929 (mean 247.9) mg/kg on a dry weight basis, respectively. The concentrations of heavy metals were higher in the internal organs than in the mantle. Of the three heavy metals, copper had the highest concentrations in the internal organs because of the existence of hemocyanin bound with copper in octopus blood, whereas zinc had the highest concentrations in the mantle. No relationship between the concentration of heavy metals and biological parameters (length, weight, and sex) was found. The ratios (I/M) of the heavy metal concentrations in internal organs and mantle were highest for cadmium, although cadmium had much lower concentrations in the internal organs compared with copper and zinc. Considering the provisional tolerable weekly intake (PTWI) of the three heavy metals and the average intake of octopus per day, all three elements should have no adverse effects on humans.

• 한국발생생물학회지:발생과생식
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• 제25권1호
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• pp.67-72
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• 2021

This study investigated the IGF-1 signal in specific tissues using Pacific oysters artificially matured via water temperature elevation. Pacific oysters were subjected to water temperature elevation from March to June, and 20 were randomly sampled each month. The condition index (CI) and tissue weight rate (TWR) were examined by measuring shell length, shell height, shell width, and soft tissue weight. The IGF-1 signal in tissues (adductor muscle, digestive glands, gills, labial palps, mantle edges, and gonads) was analyzed by sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting. From April to June, the TWR of females and males increased from 19.1±2.9 to 21.0±3.6 and 18.2±2.0 to 19.2±2.5, respectively, while the CI remained the same. The IGF-1 signal in each tissue differed. IGF-1 was expressed in the adductor muscle, while tyrosine was expressed in all tissues. The phosphor (p)-ERK and p-AKT activities were high in the adductor muscle, mantle edge, and gonads. IGF-1 signaling affected the growth and maturity of the Pacific oysters examined.

• 수산해양기술연구
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• 제58권2호
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• pp.113-120
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• 2022

The purpose of this study is to provide information about annual variations in catch size and changes in reproductive biology in the common octopus, Octopus vulgaris, a commercially important species in Jeju Island. Samples were collected from coastal waters of Jeju Island, Korea by coastal trap fishery from January to November 2021. Octopus vulgaris have been decreasing in this region since 1984. The mantle length (ML) ranged from 4.5 to 17.8 cm and body weight (BW) ranged form 88.5 to 2,657.5 g. A χ²-test revealed that the number of males was significantly greater than females (χ² = 32.712, df = 10, P<0.05). Mature females were found from January to July and male occurred January to August. The gonadosomatic index value was higher from July to August than other months. The relationship between mantle length and body weight was BW = 2.4527ML^2.3139 (female) and BW = 2.6785ML^2.3159 (male). At 50% group maturity, female and male average weight was estimated to be 554.7 g and 330.6 g, respectively.

• 한국수산과학회지
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• 제30권6호
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• pp.916-922
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• 1997

This paper attempted to estimate mesh selectivity of gill nets for neon flying squid in the north Pacific Ocean. The 11 linear regressions, (P<0.05) were obtained using the data on catch ratios derived from mesh size combinations between two slightly different mesh sizes of 12 kinds of research gillnet (namely 33, 37, 42, 48, 55, 63, 72. 76, 86, 96, 105 and 115 mm in stretched mesh size). There was an increase in the optimum length with the increase in mesh size but standard deviation showed somewhat increase with the increase in the mesh size. The selectivity curves were well fitted to the length frequency distributions obtained from samples for the mesh sizes from 48 mm through 86 mm. For the mesh sizes of 33, 37 and 42 mm the DML (Dorsal Mantle Length) compositions were distributed towards the right hand-limb of the curves. The DML distributions from the 96 mm and larger meshes showed a trend towards the left hand-limb of the curves. The selectivity curves for different mesh sizes indicate that large mesh sizes catch a greater size range of squid, and the gill net fishery in the north Pacific Ocean captures effectively neon flying squid within the range of $9\~43cm$ DML.

• 해양환경안전학회지
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• 제17권4호
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• pp.367-373
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• 2011

1985년부터 1987년까지 황해 $32^{\circ}$ 30'N, $122^{\circ}E-37^{\circ}$ 30'N, $127^{\circ}E$ 해역에서 오징어채낚기어업으로 어획된 살오징어($Todarodes$ $Pacificu$s Steenstrup)를 매월 1회 채집하여 생물학적 특성치를 조사하였다. 황해에서 어획된 살오징어의 주 발생군을 판단하기 위해 Tanaka(1956)의 방법을 사용하여 가을과 겨울발생군으로 분리하였다. 겨울발생군의 비율이 가을발생군의 비율보다 높았다. 생식소 숙도지수(GSI) 월변화에서 암컷은 1985년에는 7월에, 1986년에는 10월에, 1987년에는 8월에 최고값을 나타낸 후 감소하였다. 수컷은 1985년에는 6월에, 1986년에는 7월에, 1987년에는 6월에 최고값을 보였다. 암컷의 50% 군성숙체장를 분석한 결과 1985년에는 외투장(ML) 20.7 cm, 1986년에는 17.9 cm, 1987년에는 17.2 cm로 나타났다. 암수비율은 ML 24 cm 이상 체급에서는 암컷의 비율이 높았으며, 24 cm 미만 체급에서는 수컷의 비율이 높았다. 살오징어의 군성숙체장은 개체군 상태에 의해 영향을 받는 것으로 판단된다.