• 한국수산과학회지
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• 제34권4호
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• pp.355-358
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• 2001

본 논문은 한국 근해 다종어업 자원의 평가모델에 대한 연구결과로서 대형기선저인망쌍끌이어업과 같은 단일어업에 의하여 다종자원을 이용하는 형태이다. 단일어구에 의한 다종자원의 평가모델은 단일어구에 어획되는 다종자원 중 어획량비율이 상위를 차지하는 어종을 선별한 후 각 어종에 대한 혼획율 및 자원생태학적 특성치를 추정하여 Beverton and Holt (1957)의 가입당생산량 모델을 변형시킨 다종가입당 생산량모델을 이용하는 것이다. 이 모델은 현재의 $t_c$에서 다종에 대한$F_{0.1}$에 해 당하는 F값을 구하여 각 어종별 가입당산란자원량 모델에 적용하였으며, 이때의 산란자원량 수준인 $F_{x\%}$를 추정하여 자원평가에 이용하였다.

• 한국수산과학회지
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• 제51권3호
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• pp.254-261
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• 2018

From 2014 to 2017, mortalities of seawater-cultured rainbow trout Oncorhynchus mykiss, were observed in the Goheung and Jeju areas of Korea, with Vibrio anguillarum (seven strains: RT1, 2, 3, 4, 5, 6, and 7) identified as the etiological agent. The phenotypic (based on API 20NE, API ZYM, and E-test kits), serotypic (slide agglutination tests with O1, O2, O3, O4, and O7 antisera), and genotypic (16S rRNA and ompU sequencing) characteristics of the seven RT strains were analyzed and compared to those of seven additional V. anguillarum stains (SF, isolated from sweet fish; FM, isolated from flathead mullet; ATCC43305; ATCC43311; ATCC43307; ATCC43308; and KCTC2711). The phenotypes of the RT strains showed variance, while the slide agglutination tests of the RT1-7, SF, and FM strains all showed positive reactions with serotype O1 antiserum. The 16S rRNA and ompU sequences of the RT1-7, SF, and FM strains were affiliated with V. anguillarum ATCC43305 (Serotype O1), but the ompU sequence of the SF strain differed from those of the RT1-7, FM, and ATCC43311 strains, including one amino acid substitution. We thus confirmed that serotype O1 V. anguillarum, with multiple phenotypes, continues to infect seawater-cultured rainbow trout in Korea.

• 수산해양기술연구
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• 제56권2호
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• pp.83-93
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• 2020

In fisheries, the importance of designing efficient fish cages is being emphasized as aquaculture has become more production than capture fishing. Particularly, the gravity cage system is one of the popular fish cage system in Korea. Currently, gravity cages of various shapes and sizes are being widely designed and installed in offshore and inland seas. The cage is subject to external forces, such as currents and waves, and the shape of the structure and tension on the ropes changes according to these external forces. Thus, it is important to accurately calculate these dynamic behavior, including the external forces and tension on the structure during the design stage. In this study, three types of cage systems with an equal internal volume of 8000 ㎥ were analyzed using mass-spring models and their behavior was interpreted through simulations. These simulations were used to analyze the behavior and tension of the ropes in response to currents and waves to aid in the selection of individual cage sizes for a given total volume. The numerical calculation results indicate that depending on the flow rate, the most resistant system is System 1, which has eight strays, and System 2 and System 3 have 69.4% and 54.8% of the resistance of System 1. Further, total resistance increased as the number of cages increased for all flow rates.

• 한국양식학회지
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• 제5권2호
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• pp.109-115
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• 1992

미꾸라지 양식시 기본 요건인 종묘의 안정적 공급을 위하여 호르몬 처리에 의한 산란 유도와 연중 다산란 유도 가능성을 조사하였다. 미꾸라지는 어체중 g당 $2\~10$ IU 농도의 태반성 성선자극 호르몬(HCG) 1회 주사로 $23.1\~100{\%}$ 산란이 유발되었으며, 특히 6 IU/g의 농도 이상에서는 모든 실험어가 산란하였다. 호르몬 주사 후 산란까지 대개 $13\~25$시간이 소요되었고 HCG농도 증가에 따른 수정율, 부화율 및 위생식소 숙도지수의 변화는 관찰되지 않았다. 어체중 증가에 따라 포란수도 증가하여 어체중 g당 평균 약 $500\~600$의 난을 산란하는 것으로 나타났다. 다산란 유도를 위해 $25^{\circ}C$ 조건하에서 사육하면서 첫 산란 후 사육 일수에 따른 비만도, 간 숙도지수 및 생식소 숙도지수를 조사하고 이를 토대로 재산란을 유도한 결과 미꾸라지 암컷은 최초 산란 후 40 일이 경과하면 양질의 난을 재산란하는 것으로 나타났다.

• 한국수산과학회지
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• 제40권3호
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• pp.153-159
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• 2007

We studied oocyte steroidogenesis in relation to oocyte development in the greenling, Hexagrammos otakii, a marine multiple spawner. Vitellogenic and mature oocytes were incubated in vitro in the presence or absence of $[^3H]-17\;{\alpha}-hydroxyprogesterone$ as a precursor. The major metabolites were androgens [androstenedione $(A)_4)$ and testosterone (T)] and estrogens [$17\;{\beta}-estradiol\;(E_2)$ and estrone ($E_1$)] in vitellogenic oocytes. The metabolic rate of T was lower in 1.08 to 12-mm oocytes, while that of $E_2$ increased with oocyte size. The endogenous productions of T, $E_2$ and 17 ${\alpha}-hydroxy$, 20 ${\beta}-dihydroprogesterone\;(17{\alpha}20{\beta}OHP)$ were quantified using a radioimmunoassay in the non-precursor group. The endogenous levels of T and $E_2$ were highest in 1.08 to 12-mm oocytes and $17{\alpha}20{\beta}OHP$ was produced only in 1.90 to 95-mm oocytes. The relationship between oocyte size and steroidogenesis showed that 1.08 to 12-mm oocytes are full vitellogenic following induction of the maturation process. Moreover, $17{\alpha}20{\beta}OHP$ acts as a maturation inducing hormone in H. otakii.

• Fisheries and Aquatic Sciences
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• 제10권3호
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• pp.103-112
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• 2007

High prices, overfishing, and contamination have limited the availability of natural caviar as a food product. We attempted to apply encapsulation by calcium-alginate gel membranes to caviar analog preparation in an effort to produce a high-quality replacement for natural caviar. Physical conditions of stirring speed $(X_1,\;rpm)$ and gelation time $(X_2,\;min)$ as the independent variables for gelation were optimized by response surface methodology. Sphericity $(Y_1,\;%)$, diameter $(Y_2,\;mm)$, membrane thickness $(Y_3,\;mm)$, rupture strength $(Y_4,\;g)$, and rupturing deformation $(Y_5,\;mm)$ were used as the dependent variables to compare characteristics of the capsules for caviar analogs with natural caviar. The values of the independent variables as evaluated by multiple response optimization were $X_1=-0.1271 (278 rpm) and $X_2=0.4436$ (12.2 min), respectively. Predicted values of the four dependent variables were $Y_1=97.7%,\;Y_2=2.97mm,\;Y_4=1,465g,\;and\;Y_5=1.15mm$. Membrane thickness $(Y_3)$ was eliminated from the dependent variables for multiple response optimization because it could not be measured with an image analyzer. The experimental values prepared under the optimal conditions for verification nearly coincided with the predicted values and satisfied the conditions of natural caviar.

• 한국버섯학회지
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• 제8권1호
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• pp.1-5
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• 2010

버섯의 다원적 기능은 생리활성 기능, 가축 사료생산 기능, 유기질 비료 생산 기능, 생태계 분해자로서의 기능, 환경 오염물질 정화 기능, 식품 영양학적, 기호 식품적, 생리활성 기능 이다. 이 중 생리활성 기능, 가축 사료생산 기능, 유기질 비료 생산 기능과 생태계 분해자로서의 기능은 정량화를 하였고 그 나머지 기능은 정량화하는 연구가 더 필요하였다. 정량화된 버섯의 다원적 기능을 경제적 가치로 환산하면 112조 922억원이며 정량화하지 못한 부분까지 합하면 이의 2배 이상될 것으로 추정한다. 이렇게 추정할 경우 쌀의 다원적 기능 약 100조원의 경제적 가치에 비해 버섯은 거의 비슷한 가치가 있다고 볼 수 있다. 버섯의 생리활성물질 베타글루칸의 산업적 가치는 약 112조원, 가축 사료생산 기능은 약 618억원, 유기질 비료생산 기능은 약 56억원, 생태계 분해자로서의 기능은 약 360억원으로 나타났다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1998년도 Proceedings of International Symposium on Remote Sensing
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• pp.236-241
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• 1998

The NOAA AVHRR remote sense SST data, collected by the National Fisheries Research and Development Institute (NFRDI), are analyzed in order to understand the spatial and temporal distributions of SST in the seas adjacent to Korea. Our study is based on 10-day SST images during last 7 years (1991-1997). For a time series analysis of multiple 557 images, all of images must be aligned exactly at the same position by adjusting the scales and positions of each SST image. We devised an algorithm which yields automatic detections of cloud pixels from multiple SST images. The cloud detection algorithm is based on a physical constraint that SST anomalies in the ocean do not exceed certain limits (we used $\pm$ 3$^{\circ}C$ as a criterion of SST anomalies). The remote sense SST data are tuned by comparing remote sense data with observed SST at coastal stations. Seasonal variations of SST are studied by harmonic fit of SST normals at each pixel. The SST anomalies are studied by statistical method. We found that the SST anomalies are rather persistent with time scales between 1 and 2 months. Utilizing the persistency of SST anomalies, we devised an algorithm for a prediction of future SST Model fit of SST anomalies to the Markov process model yields that autoregression coefficients of SST anomalies during a time elapse of 10 days are between 0.5 and 0.7. We plan to improve our algorithms of automatic cloud pixel detection and prediction of future SST. Our algorithm is expected to be incorporated to the operational real time service of SST around Korea.

• 한국수산과학회지
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• 제42권5호
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• pp.434-441
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• 2009

This study was conducted to compare the biological activities of 7 melania snails from the family Pleuroceridae (Semisulcospira coreana, Koreanomelania nodifila, Semisulcospira forticosta, Koreoleptoxis globus ovalis, Semisulcospira libertina, Semisulcospira tegulata and Semisulcospira gottschei) in Korea. Among the 7 species, S. coreana, Korean. nodifila, S. forticosta and S. gottschei showed over 80% cytotoxicities on three cancer cell lines (SNU-1, A549 and Hep 3B) compared to the non-treatment, whereas S. libertina and S. tegulata showed almost no growth inhibition activities on the same cancer cell lines. In relation to ACE inhibition activity, only S. coreana, Korean. nodifila, and S. forticosta showed over 60% ACE inhibition activities, whereas other melania snails exhibited inhibition activities of lower than 25%. DPPH radical scavenging activities were also determined, and used to categories melania snails into three groups based on Duncan's multiple range test at P<0.05. The amount of TNF-${\alpha}$ produced by in vitro mouse peritoneal macrophage was determined according to bioactivity on L-929 cells. Three melania snails, S. coreana, Korean. nodifila and S. gottschei, exhibited 95.2%, 89.7% and 93.7% cell death(%) on L-929 cells, respectively. Glucose-6-phosphate dehydrogenase inhibitory activity was also obtained in the extract of S. coreana (31.9%) and Korean. nodifila (28.1%), showing that these extracts can be used as supplemental dietary health foods. In conclusion, we believe that the extracts of melania snails should be given due consideration in functional health food development.

• 한국수산과학회지
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• 제52권5호
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• pp.461-467
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• 2019

Several studies investigating the prevention and treatment of external parasites in farmed olive flounder Paralichthys olivaceus have found that the anticoccidial agent toltrazuril sulfone is an effective antiparasitic. Prior to undertaking a full-scale study, we developed analytical methods to detect the levels of toltrazuril and toltrazuril sulfone in farmed flounder samples using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-MS/MS). This analysis showed that LC-MS/MS changed the mobile phase and collision energy of toltrazuril and toltrazuril sulfone. This was validated using established conditions. Sample pre-treatment for this process involved extraction with dichloromethane and purification by liquid-liquid extraction in formic acid, acetonitrile, and h-hexane, followed by determination of all compounds by LC-MS/MS. Separation was achieved within 10 min by gradient elution using a Capcell Pak C18 ($3.0{\mu}m$, $100{\times}2.0mm$) analytical column (Shiseido UG 120V) with a mixture of 0.1% (v/v) formic acid and acetonitrile. Multiple reaction monitoring was used for selective detection of toltrazuril and toltrazuril sulfone. This method yields satisfactory results for linearity, precision, and limits of quantification. Therefore, the method established in our study will serve as a basis for further research on parasite control by toltrazuril and toltrazuril sulfone.