• Proceedings of the Acoustical Society of Korea Conference
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• 1992.06a
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• pp.127-130
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• 1992

한국 근해에서 능동소나 (active sonar) 사용시 사용되는 environmental parameters 가운데 하나인 volume reverberation(REv)을 산출하기 위하여 플랑크톤에 의한 후방산란 강도(backscattering strength)에 대한 연구를 하였다. 이를 위하여 수산진흥원 자료(80-89년)중 부유생물조사표에서 후방산란 강도가 다른 종에 비하여 큰 copepoda의 개체수를 평균한 후, 수심별 개체수를 계산하여 수심별, 주파수별(10, 50kHz), 계절별(2월, 8월) 후방산란 강도와 multipath eigenray model을 이용하여 REv를 산출하였다. 예로 사용한 동남해역(zone:S3), 서해중부해역(zone:W3)에서 주파수별 REv는 일반적인 형태인 포기에는 고주파가 높고, 1.5초 이후에는 저주파가 높게 나타났다. 그러나 여름이 겨울보다 플랑크톤 개체수가 많아 후방산란 강도가 크지만(2-5dB), REv는 겨울이 더 크게 나타났다. 이러한 이유는 SVP profile에 의한 pressure 계산결과, 여름에는 ray가 down-ward이고 겨울에는 duct를 형성하여 ray가 거의 direct로 진행하므로 transmission loss가 여름이 크기 때문이다. 또한 ray tracing결과 여름철에는 ray crossing이 많아 겨울에 비하여 fluctuation이 심하게 나타나는 현상을 보이고 있다. 두 지역 이외에도 한국근해의 정확한 REv을 예측하기 위해서는 플랑크톤의 정확한 측정과, 이론적인 수치와 비교할 수 있는 실측치를 얻는 것이 필요하다고 볼 수 있다.

• KOREAN POULTRY JOURNAL
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• v.24 no.2 s.268
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• pp.131-135
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• 1992

겨울철 산란육성계와 브로일러에서 장염, 미숙변, 연변, 계사과습 등으로 증체, 폐사, 도태율이 증가하여 생산성이 저하되며 산란성계 편입 후에도 능력을 최대한 발휘하지 못하여 고심한다. 여름철에는 콕시듐증이 문제이지만 겨울철은 방한시설에 치중하다보면 장염성 살모넬라증을 일으켜 눈에 보이지 않게 손실을 보게 된다. 닭에서 상기원인체인 살모넬라증은 인수공통전염병(人獸共通傳染病)의 하나로 닭은 물론 사람에게도 오염된 닭고기, 계란을 먹고서 때때로 식중독 증상을 일으킨다. 아울러 닭에서도 과습고온 사육시 연변, 하리, 장염, 소화장해 등으로 생산성 저해 소화기 질병을 일으킨다. 이 달에는 본 질병의 근본원인체인 살모넬라 장염에 대하여 기술한다.

• Korean journal of applied entomology
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• v.53 no.3
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• pp.225-229
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• 2014

Seasonal changes in the firefly (Luciola lateralis) were studied in the laboratory to understand biological characteristics. Fecundity varies with seasons; these were measures at $162.0{\pm}8.67$ in the winter, $226.9{\pm}15.84$ in the spring and $166.6{\pm}9.3$ in the summer. Seasonal change also influenced oviposition period ($6.9{\pm}0.59$ days in the winter, $16.1{\pm}1.10$ days in the spring and $8.2{\pm}0.61$ days in the summer). The firefly oviposited every $2.5{\pm}0.22$ days in the winter, $3.9{\pm}0.25$ days in the spring, and $2.3{\pm}0.14$ days in the summer. Oviposition occurred 3 times in the winter, and 4 times in the spring and summer. The number of eggs per cycle was $52.2{\pm}4.56$ and $55.9{\pm}4.38$ in winter and spring, respectively, and was lower in the summer ($42.2{\pm}3.76$). Egg period significantly differed among seasons. The life span of the firefly was $17.9{\pm}0.14$ days in the winter, $19.7{\pm}0.25$ days in the spring and $16.5{\pm}0.43$ days in the summer.

• KOREAN POULTRY JOURNAL
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• v.26 no.12 s.302
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• pp.111-114
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• 1994

• KOREAN POULTRY JOURNAL
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• v.27 no.2 s.304
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• pp.76-79
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• 1995

• Korean journal of applied entomology
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• v.35 no.3
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• pp.205-208
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• 1996

Psylla pyricola population from Suwon($37^{\circ}$16' N) begins to enter diapause by exposure to a photoperiod of 14hr light. Over 93% of adults were induced to enter diapause when exposed to 13hr loght period, and at 18 and $25^{\circ}C$, the critical photoperiod was not influenced. When the photoperiod was switched during the nymphal stage from 16L to 10L, no morph change was occurred in the 4th and 5th instars. Average number of eggs laid per female was 486.2 in winter form adult and 387.2 in summer form adults, and average oviposition periods were 34 and 24 days, respectively.

• 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.

• KOREAN POULTRY JOURNAL
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• v.45 no.11
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• pp.156-158
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• 2013

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.33 no.2
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• pp.97-108
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• 1997

Variation of the catches and fishing grounds, and spawning ecology of Lophius litulon caught by large staw net were investigated from following as ; L. litulon caught through the year, and the peak in catches showed on January in winter, and the lowest catches showed on August in summer. The fishing grounds of L. litulon were located in the Yellow Sea and the East China Sea. And the main fishing ground was formed in the adjacent waters of Ilhyang-cho, where catches and CPUE were more than 50 M/T, 5 kg/haul, respectively, and the range of coefficient of variation(C.V) was 0.6~0.7. The spawning season of L. litulon was on March and April, when spawning area was formed in waters between Ilhyang-Cho and Cheju-Do. The fishing grounds distribution of L. litulon was obviously different with seasonal variation. Namely, in winter, the fishing grounds were mainly formed in the western waters of Cheju-Do, and on March and April( in spawning season), the fishing grounds were densely formed in the adjacent waters of Ilhyang-Cho, and after May, the fishing grounds were widely dispersed towards in the Yellow Sea and the East China Sea with temperature upgrade.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2001.05a
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• pp.338-339
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• 2001

대게의 산란은 일본 서ㆍ남해 근해에서 겨울∼봄에 이루어지는 것으로 보고된 바있으나 (Yoshida, 1941; Ito, 1963), 이 결과는 자연산 채집에 의한 생태학적인 방법으로 접근한 것이 대부분이며, 일본의 대게 분포수역과 인접한 우리나라 동해안 울진, 축산 근해의 대게 성숙과 산란에 관한 비교자료는 거의 없다. 또, Lim et al.(1998)은 동해안 대게 유생의 부화실험에서, 부화시기가 12월경이라고 하였는데, 앞으로 지역적인 성숙시기의 차이를 검토해 볼 필요가 있다. (중략)