• The Korean Journal of Malacology
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• v.25 no.1
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• pp.23-28
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• 2009

Samplings have been monthly collected in Jeju Island, Korea, using ser nets. A total of 759 individuals were sampled from June to November 2006. We analyzed mantle length distribution, monthly changes in maturity stages, maturation size and sex ratio. Mean Mantle length of the female specimens ranged from 6.7 to 50.3 cm and that of the male specimens ranged from 6.7 and 50.0 cm. The spawning period was November. The Mantle length at 50 % group maturity was estimated to be 17.1 cm. Sex ratio was 1 : 1.3 (male : female), suggesting the female population may be predominant.

• Journal of Aquaculture
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• v.13 no.3
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• pp.245-251
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• 2000

Carapace width (CW) of main size class of the snow crab was 70~90 mm for females and 80~100 mm for males. The CW holds a stronger relation with body weight than that of carapace length (CL). The number of eggs attached to the pleopods was in the range of 35,000 and 114,000 eggs in crabs with 65 and 88 mm CW, respectively). The logistic maturity curve on morphometric measurements and gonad examination, defined by the presence of egg brooding in wide abdomen of the female and spermatophores inside the vasa deferentia of the male indicated that 50 % of crabs attained gonadal maturity at 54.2 mm and 58.8 mm CW for females and males, respectively. In the relationship between CW and body weight, a sharp break at 53~55 mm CW indicates that morphological changes associated with maturity have occurred.

• Korean Journal of Plant Taxonomy
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• v.43 no.2
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• pp.128-138
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• 2013

The conservation status of an endemic perennial herb, Hanabusaya asiatica (Nakai) Nakai (Campanulaceae) was determined by applying the IUCN risk assessment criteria from our field study and available specimen data. Also, the GIS technology was used to develop a species distribution map to calculate the extent of occurrence (EOO) and area of occupancy (AOO) for the taxon. After two years of continuous field studies, 269 mature individuals were found in four localities in 2011, while 216 mature individuals were confirmed in three localities in 2012. Based on the following data, such as EOO (2,742 $km^2$), AOO (76 $km^2$) and estimated population size of mature individuals, the taxon, which is known as 20 localities in Korean peninsula, is evaluated as the category of Endangered (EN). A major difficulty in application of IUCN criteria to Korean rare plants were the lack of essential biological information and understanding the correct knowledge of the IUCN criteria in previous Korean studies. Sound conclusions regarding the conservation status of individual species require more intensive population studies, observations, and applying IUCN assessment procedures correctly.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.10a
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• pp.139-139
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• 2003

최근, 한우의 수정란 체외이식두수가 급격히 늘어나고 있으나, 모축의 등록번호를 대부분 확인 할 수 없으며, 확인이 가능할지라도 개체별 수정란의 생산이 거의 이루어지지 않고 있다. 본 실험에서는 모축의 등록번호가 확인된 개체의 난소로부터 채취한 난포란만을 체외성숙, 수정, 배양하여 배 발생율을 조사하고, 동결성적을 조사하였다. 도축된 한우의 난소를 개체별로 채취하여 2$0^{\circ}C$생리식염수에 넣어 3시간 이내에 실험실로 운반하고, 난포란을 채취하였다 개체별로 채취한 난포란은 9~47개/난소였고, 평균 14.3개/난소였다. 개체별 난포란은 IVMD 101 (일본, 펩티트연구소)에서 22물24시간 동안 체외 성숙시킨 후, IVF 100(일본, 펩티트연구소)으로 2회 세정한 후, 각각의 배양액 50${\mu}\ell$ 소적에 5개씩 5~6시간 수정시켰다. 수정란을 저 산소 배지 IVD 101 (일본, 펩티트연구소)로 7~9일간 배양하여 배 발생율을 조사하고 동결하였다. 평균 수정율은 81%, 배반포의 발생율은 35% 였으며, 동결 가능한 수정란은 평균 4개/두 정도 얻을 수 있었다. 이상의 결과로 한우의 개체가 확인된 난소로부터 수정란생산이 가능하고, 육질등급이 우수한 한우의 수정란생산이 가능해졌으며, 앞으로 고 능력 젖소의 난소에서도 고능력 수정란의 생산이 가능할 것으로 사료된다.

• Korean Journal of Ichthyology
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• v.29 no.2
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• pp.109-116
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• 2017

We investigated maturation and spawning of Miichthys miiuy in the south-western water of Korea, based on samples collected by stow net from August 2015 to December 2016. We analysed monthly changes in maturity stage, gonadosomatic index (GSI), total length (TL) at 50% group maturity. The spawning period was August to October. We estimated the TL at 50% group maturity as 54.8 cm for females and 49.0 cm for males.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 1998.07a
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• pp.39-40
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• 1998

수온과 광주기를 조절한 실험구는 대조구에 비해 GSI의 peak가 2개월 늦어졌으며, 난소의 발달도 지연되었다. 암컷 혈중의 $E_{2}$와 T 농도도 성숙 단계의 지연에 따라 peak가 각기 다르게 나타났다. 그러나 수온과 광주기를 조절한 그룹의 일부개체는 성숙이 지연되지 않았으며, 수컷의 GSI나 수컷 혈중의 T 농도도 수온과 광주기의 변화에 영향을 받지 않았다.

• Journal of Korean Library and Information Science Society
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• v.55 no.1
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• pp.215-237
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• 2024

This study proposes a selection plan for research entities and PIDs and a strategy for building and operating a PID consortium based on a survey of advanced cases of research entities and PID operations in major countries such as the United Kingdom, Germany, Canada, Japan, China, and Australia. The criteria for selecting research entities and PIDs are 'research life cycle' and 'PID infrastructure maturity'. Based on the two selection criteria, it is proposed to prioritize research entity-PID pairs such as 'Researcher-ORCID', 'Publication-DOI', 'Data-DOI', 'Institution-ROR', 'Grant-DOI', and 'Project-RAiD' and expand to other research entities and PIDs in the emerging stage. The strategy for establishing and operating a PID consortium should encourage the participation of various PID stakeholders, identify the latest trends through collaborative networks with domestic and international PID organizations, lead education and outreach activities to raise awareness and increase utilization of PID, and secure policy support and financial stability. This is expected to lay the foundation for domestic research entities to gain visibility and accessibility at the global level.

• The Korean Journal of Malacology
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• v.25 no.2
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• pp.127-133
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• 2009

The common octopus, Octopus vulgaris is commercially important species in Korea. Korean fishing vessels have actively caught it. However, the study of this species has been poorly known. Therefore, the purpose of this study is to provide information about maturation and spawning period of this species. Samplings have been monthly collected in Tongyoung and Sacheon of Gyeongsangnam-do, using traps. A total of 748 individuals were sampled from February 2007 to January 2008. We analyzed monthly changes in maturity stages, gonadosomatic index, total weight at 50% group maturity. The octopus total weight was between 128.6 and 3381.4 g. Females were distributed between 129.8 and 3381.4 g and males between 128.6 and 2378.4 g. The spawning periods were May to June and September. The total weight at 50% group maturity was estimated to be 919.6 g.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.4
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• pp.380-385
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• 2002

The sand shrimp, Crangon hakodatei commonly occured in the southern coast of Korea. The population structure, growth, mortality, and size at sexual maturity of C. hakodatei were examined by the samples collected from the coastal area of Geoje Island, Korea from October 2000 to October 2001. For estimation of parameters of growth and mortality, monthly length-frequency data were analysed by ELEFAN. Parameters of growth were estimated, using the modified yon Bertalanffy growth function model. The female grew faster and reached larger size at the same age than the male, There was a breeding season showing a peak in winter (January to february). Total mortality by length-converted catch curve was estimated at $3.10 yr^{-1}$, fishing mortality was $0.62 y^{-1}$ and natural mortality was $2.48 yr^{-1}$. The size at $50\%$ sexual maturity for the female ranged from CL 11.00 to 11.50 mm.

• The Korean Journal of Malacology
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• v.25 no.2
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• pp.173-178
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• 2009

The bigfin reef squid, Sepioteuthis lessoniana is commercially important species in Korea. Korean fishing vessels have actively caught it. However, the reproductive Biology of this species has been poorly known. Therefore, the purpose of this study is to provide information on the reproductive biology of Sepioteuthis lessoniana in Jeju Island, Korea. The bigfin reef squid caught by set net, from June to November 2006. Monthly changes in maturity stages, gonad weight, mantle length at 50% group maturity and sex ratio were investigated. The mantle length of the bigfin reef squid was between 10.6 and 32.1 cm. Maturation and spawning occur all year around, with more intensity from July to September, with peak July. The spawning period was June. The mantle length at 50% group maturity was estimated to be 18.01 cm. Sex ratio was 1:1.4 (male:female). The proportion of female was significantly higher than male ($x^2$-test, p > 0.01).