• Proceedings of the Korea Contents Association Conference
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• 2015.05a
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• pp.167-168
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• 2015

고에너지 의료용 선형가속기를 이용한 폐암 방사선치료 시 갑상선에 미치는 선량을 평가하였다. 산란광자의 영향은 3DCRT 시 평균 27.9mSv, IMRT에 있어서는 43.6mSv로 평가 되었다. 광중성자의 영향은 3DCRT 시 평균 3.2mSv, IMRT에 있어서는 평균 4.7mSv로 평가 되었다. 산란광자와 광중성자 모두 3DCRT 보다 IMRT가 높은 것으로 평가 되었다. 본 연구를 통하여 고에너지를 이용한 방사선치료 시 인접한 정상조직에 상당한 양의 산란선량이 영향을 주는 것으로 평가된 바와 같이 방사선을 이용한 암 치료 종사자는 이러한 내용을 충분히 인지하여 피폭 저감화를 위한 노력이 필요할 것으로 사료된다.

• Proceedings of the Korea Contents Association Conference
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• 2014.11a
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• pp.181-182
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• 2014

고에너지 의료용 선형가속기를 이용한 폐암 방사선치료 시 갑상선에 미치는 선량을 평가하였다. 산란광자의 영향은 3DCRT 시평균 27.9mSv, IMRT에 있어서는 43.6mSv로 평가 되었다. 광중성자의 영향은 3DCRT 시 평균 3.2mSv, IMRT에 있어서는 평균 4.7mSv로 평가 되었다. 산란광자와 광중성자 모두 3DCRT 보다 IMRT가 높은 것으로 평가 되었다. 본 연구를 통하여 고에너지를 이용한 방사선치료 시 인접한 정상조직에 상당한 양의 산란선량이 영향을 주는 것으로 평가된 바와 같이 방사선을 이용한 암치료 종사자는 이러한 내용을 충분히 인지하여 피폭 저감화를 위한 노력이 필요할 것으로 사료된다.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.6
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• pp.536-542
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• 1984

Fish eggs and larvae in the western waters of Korea are surveyed during the periods from February to August in 1982. Six species of eggs and forty-two species of larvae are occurred in the survey area. The dominant species occurred during the study periods are Ammodytes personatus, Enedrias sp., Engraulis japonica, Callionymus sp., Gobiidae, etc. Major spawning month and ground of each species are estimated from the data, i.e., occurrence month and abundance of eggs and larvae by survey month and area, as well as the optimum water temperature and salinity for spawning.

• Korean Journal of Ichthyology
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• v.5 no.2
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• pp.194-207
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• 1993

This paper deals with seasonal fluctuation of fish communities around the coast of Kunsan, Korea from 1992 to 1993. A total of 98 fish species with 82 genera, 47 families, and 14 orders were collected during the study. Among fishes caught by trawl net, Cynoglossus joyneri and Repomucenus ornatipinnis predominated throughout the year, and by long back net Harengula zunasi and Engraulis japonica except winter season. There is a difference between biomass caught by long back net and by trawl net, the former showing a peak in summer and the latter showing peaks in late spring and winter. This result appears to be due to the occurrences of Platycephalus indicus and Liparis tanakai for the spawning in investigated areas. Among the 14 species collected in the intertidal zone, 13 species of the family Gobiidae were mostly found in the spawning season. These results may suggest that the coastal area of Kunsan provides a good spawning ground for the coastal fishes. It is considered that the seasonal fluctuation of the abundance and species composition in fishes in this area is mainly affected by the water temperature and the bottom habitats.

• Proceedings of the Korea Water Resources Association Conference
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• 2020.06a
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• pp.47-47
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• 2020

하천 유사량 자료는 하천관리를 위해 기초적으로 활용되는 자료로 하천의 유지관리를 위한 유사량 자료의 측정은 필수적이다. 따라서, 현재 국내에서는 전국에 138개소의 국가유사량관측망에서 지속적인 유사량 측정을 수행하고 있지만, 기존의 재래식 부유사 채집기를 이용한 부유사 측정을 수행하고 있어 연간 약 20개소 내외에서만 직접조사가 수행되고 있고, 2019년도 기준 전국 138개소 중에서 2006년~2018년 동안 최소 1회 이상 유사량 측정을 수행한 지점은 40개소로 국가 유사량관측망의 약 29% 지점에 대해서만 조사가 수행되고 있다. 해외의 경우에도 기존 재래식 채집기를 통한 유사량 관측을 주로 수행하고 있지만 최근에는 기존 채집기를 이용한 유사량 조사방법의 고비용·저효율로 인한 시공간적 한계로 인해 대안기술이 개발되고 있다. 특히, 최근 해외에서는 ADCP를 활용한 유사량 측정 기술이 기존 부유사 채집기를 이용한 유사량 조사방법의 대안으로 시도되고 있다. ADCP를 이용한 유사량 측정방법은 ADCP의 초음파산란도를 활용하여 간접적으로 부유사의 농도를 추정하는 기술로 ADCP를 이용하여 유량자료과 함께 유사량 자료를 확보할 수 있을 것으로 기대되는 기술이다. 특히, 기존에 설치된 국가하천 자동유량측정장치(H-ADCP)에 적용이 가능하다면 다지점에서의 지속적인 유량측정과 함께 부유사 농도의 측정이 가능할 것으로 기대되고 있다. 이에 본 연구에서는 기존 국가하천에 설치되어 있는 자동유량측정장치(H-ADCP)의 초음파산란도를 활용한 부유사농도 측정 기술의 적용성을 검토하였다. 적용성의 검토를 위해 2016년 진동지점에서 수집된 H-ADCP 원시자료를 사용하여 초음파산란도를 활용한 부유사농도 측정 방법을 시범적으로 적용하였다. 적용결과, 실측 부유사농도와 H-ADCP로부터 추정된 부유사 농도를 비교를 통해서 H-ADCP를 활용한 부유사농도 측정 방법의 가능성을 확인할 수 있었지만, 기술적인 보완 및 개선이 필요할 것으로 판단되었다. 추후에는 지속적인 연구를 통해 ADCP 유사량 측정기술이 개발된다면 기존 부유사 채집기를 이용한 유사량 측정 방법의 대안으로 유사량 조사를 목적으로 활용이 될 수 있을 것으로 기대한다.

• Korean Journal of Ichthyology
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• v.23 no.4
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• pp.261-268
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• 2011

To clarify the annual reproductive cycle of the Korean perch, Coreoperca herzi, the seasonal changes in gonadosomatic index (GSI), hepatosomatic index (HSI), histological aspects of gonad and liver, and plasma levels of sex steroid hormones were investigated from June 1994 to April 1996. The annual variations of GSI and HSI were positively related to the plasma levels of sex steroid hormones. Estradiol-$17{\beta}$ (E2) and testosterone levels were raised during the April to May. Based on the related results, annual reproductive cycle of the fish could be divided into five successive stages; 1) Growing stage (from February to March: GSI was increased rapidly and oocytes with yolk vesicle was increased. Nucleus migrates toward the animal pole. Spermatids were activated from the epithelial tissue of lobuli). 2) Maturation and spawning stage (from April to June: Oocytes were accumulated yolk globules. Active spermatogenesis was observed). 3) Degeneration or stagnation phase (from July to August). 4) Recovery phase (from September to November) and 5) resting phase (from December to January). The main spawning period was in May.

• 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.

• Development and Reproduction
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• v.9 no.2
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• pp.123-134
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• 2005

Germ cell development during oogenesis, ovarian maturation and first sexual maturity in female Ruditapes philippinarum were investigated by cytological and histological observations. R. philippinarum is dioecious. During vitellogenesis, the Golgi complex, glycogen particles, and mitochondria were involved in the formation of lipid droplets and lipid granules in the cytoplasm of the early vitellogenic oocyte. In the late vitellogenic oocyte, cortical granules, the endoplasmic reticulum, and mitochondria were involved in the formation of proteid yolk granules in the cytoplasm. At this time, exogenous lipid granular substance and glycogen particles in the germinal epithelium passed into the oocyte through the microvilli of the vitelline envelope. The spawning period was once a year between early June and early October, and the main spawning occurred between July and August when seawater temperature was approximately $20^{\circ}C$. The reproductive cycle of this species can be categorized into five successive stages: early active stage(January to March), late active stage(Februaryto May), ripe stage(April to August), partially spawned stage(May to October), and spent/inactive stage (August to February). Percentages of female clams at first sexual maturity of $15.1{\sim}20.0mm$ in shell length were 52.6%(50% of the rate of group maturity was 17.83mm in length), and 100% for the clams >25.1mm.

• Korean Journal of Ichthyology
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• v.12 no.3
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• pp.192-202
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• 2000

Reproductive biology of the slimy, Leiognathus nuchalis was investigated by means of histological methods. Sex ratio was 1.81 : 1 in female to male. Developmental pattern of oocytes was group-synchronous. Testicular structure was restricted spermatogonial testis-type of tubular testis. The size of first group maturity is 7.5 cm in total length. Gonadosomatic index(GSI) of female was the highest in July(12.83) and the lowest in September(1.08). GSI of male was the highest in June(19.0) and the lowest in October(0.24). Hepatosomatic index(HSI) of female showed to be positively correlated with GSI. Thoracic spot index(TSI) showed to be the minimum value from May to July when the maturation and ripe season of gonad. Reproductive cycle of female could be classified into the growing(March~May), maturation(May~June), ripe and spent(June~August), recovery(August~November), and resting stage(November~March). Reproductive cycle of male could be classified into the multiplicative and growing(January~April), maturation(April~May), ripe and spent(June~August), recovery(August~October), and resting stage(October~December).

• Korean Journal of Poultry Science
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• v.37 no.4
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• pp.361-372
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• 2010

Serological evaluation for the poultry is important for various reasons, such as designing and assessing the vaccination program and diagnosing diseases and for this reason, serologic tests for the layer flocks have been conducted on a regular basis. Moreover, the nationwide serological survey and analysis are essential to understand the epidemiological status of national poultry industry. In this sense, the study was conducted to evaluate the immune status of the layer flocks with the sera submitted to Avian Disease Laboratory, Chungbuk National University in 2009, and several important viral diseases were selected for evaluation including low pathogenic avian influenza (LPAI), Newcastle disease (ND), infectious bronchitis (IB) and avian metapneumovirus (aMPV). For LPAI and ND, the age-related patterns of geometric mean titer (GMT) changes were similar but there were differences in the flock positive rate and the level of GMT due to the different vaccination policy. In the case of IB, the values of GMT showed that the field infection was more prevalent than expected. For aMPV, positive birds in a flock increased as the layers got older, which reflected the course of field infection because vaccination against aMPV was not allowed in 2009. From this study, the immune status for the main viral diseases in layers became more clarified but this information was limited because of only one year study. Therefore, serological survey needs to be conducted on a yearly basis and furthermore include broilers and breeders for a better understanding of the health status in the national poultry industry.