• Proceedings of the KSRS Conference
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• 2009.03a
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• pp.40-45
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• 2009

본 연구에서는 기후 등의 영향을 받지 않고 레이더 산란 측정을 할 수 있는 X-band antenna 기반의 자동관측 시스템을 이용하여 벼 생육시기에 따른 후방산란계수와 벼 생육인자와의 관계를 분석하여 후방산란계수를 이용한 벼 생육인자를 추정한 것을 목적으로 하였다. 2008년도 국립농업과학원 시험포장 ($37^{\circ}$15'28.0"N, $126^{\circ}$59'21.5"E)에서 추청벼를 대상으로 생육시기별 후방산란계수를 관측하였는데 모든 편파별 후방산란계수가 벼 유수형성기 (7월 말경)까지 증가하다가 그 후 감소하다가 수확기가 가까워지는 9월 중순이후 다시 증가하는 dual-peak 현상을 보였고 특히 W-편파의 경우 9월 초순부터 후방산란계수 증가가 다른 polarization에 비해 크게 나타났다. 후방산란계수와 작물생육인자와의 관계를 분석한 결과 고주파수인 X-band는 상대적으로 바이오메스, 엽 면적지수와의 상관이 낮게 나타났지만 이삭 건물중은 VV-편파 후방산란계수와 상관관계를 보였다. 이삭 건물중과 상관관계가 높게 나타난 X-band의 W-편파 후방산란계수를 이용하여 수확기 이삭 건물중을 추정하였는데 VV-편파 후방산란계수와 이삭 건물중과는 결정계수 $(R^2)$가 0.85이었고, 이삭 건물중 실측값과 추정값을 비교해 본 결과 1:1 line에 근접하게 분포하였다 ($R^2$=0.85).

• Korean Journal of Ichthyology
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• v.18 no.1
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• pp.27-35
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• 2006

During spawning season of female in a Korean oily bitterling, Acheilognathus koreensis, the ventral region near the base of the pectoral fin becomes to be protruded outward of body and enlarged. This ventral process consists of both organs as rectum (vent) and inner ovipositor. The rectum consists of mucosa, lamina propria-submucosa, muscularis, and squamous epithelial layer (peritoneum=serosa) surrounding them. The mucosa contains numerous mucous cells meaning acid mucopolysaccharides in nature. The inner ovipositor is similar to that of the rectum, but the mucosa have no mucous cell, unlike that of the rectum. Whereas, the outer ovipositor has a straight and long tube which are not connected with the ventral process any more. The outer ovipositor was similar to the structure of the inner ovipositor in the ventral process. However, the outer ovipositor has no muscularis, and consists of three layers: mucosa, lamina propria-submucoa, and squamous epithelia. The outer ovipositor without the muscularis seems serves as a tube that eggs discharged from the outer ovipositor allow to send inside mussel, unlike that of the inner ovipositor performing rhythmic contractions of the layers of the muscularies for propelling to the matured oocytes to the outer ovipositor.

• Korean journal of applied entomology
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• v.42 no.1
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• pp.43-51
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• 2003

This study was carried out to develop the forecasting model of Pseudococcus comtocki Kuwana for timing spray. Field phonology and temperature-dependent development of p. comstocki were studied, and its stage transition models were developed. p comstocki occurred three generations a year in Suwon. The 1 st adults occurred during mid to late June, and the 2nd adults were abundant during mid to late August. The 3rd adults were observed after late October. The development times of each instar of p. comstocki decreased with increasing temperature up to 25$^{\circ}C$, and thereafter the development times increased. The estimated low-threshold temperatures were 14.5, 8.4, 10.2, 11.8, and 10.1$^{\circ}C$ for eggs, 1st+2nd nymphs, 3rd nymphs, preoviposition, and 1st nymphs to preoviposition, respectively. The degree-days (thermal constants) for completion of each instar development were 105 DD for egg,315 DD for 1st+2nd nymph, 143 DD for 3rd nymph, 143 DD for preoviposition, and 599 DD for 1 st nymph to preoviposition. The stage transition models of p. comstocki, which simulate the proportion of individuals shifted from a stage to the next stage, were constructed using the modified Sharpe and DeMichele model and the Weibull function. In field validation, degree-day models using mean-minus-base, sine wave, and rectangle method showed 2-3d, 1-7d, and 0-6 d deviation with actual data in predicting the peak oviposition time of the 1st and 2nd generation adults, respectively. The rate summation model, in which daily development rates estimated by biophysical model of Sharpe and DeMichele were accumulated, showed 1-2 d deviation with actual data at the same phonology predictions.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.19 no.1
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• pp.35-40
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• 2014

Hatching date, main spawning period and growth of juvenile marbled flounder (Pseudopleuronectes yokohamae) were determined by analysis of microstructure in otoliths. Marbled flounders were collected by a small beam trawl in Namhae from February 2011 to January 2012. The length (L, mm) was related to body weight (W, g); $W=9.76^*10^{-8}L^{4.39}$ ($r^2=0.93$). The length was also related to otolith radius (R, ${\mu}m$); L=0.0795R+0.2249 ($r^2=0.92$). The growth in length was represented by Gompertz growth curve; $L_t=135{\exp}\{-{\exp}[0.0103(t-116)]\}$ ($r^2=0.83$). The hatching date calculated from the number of daily growth increments in otoliths was between mid-December and mid-February.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.5
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• pp.550-555
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• 1999

The growth and spawning time of juvenile Ammodytes personatus were analyzed based on the daily growth increment in otolith reading of the sample caught in the coastal waters of Shinsudo, Sacheon from March 20 to May 1, 1988. Daily growth increment in otolith was formed once a day. The estimated spawning time ranged from November, 1987 to March, 1988. The von Bertalanffy growth model and the Gompertz growth model were expressed as, $TL=87.80(1-e^{-0.0074(t+10.79)})$ and $TL=72.59 e^{-1.8417\;e-0.0152t}$ respectively, where TL is total length in mm, t is age in day.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2003.11a
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• pp.109-110
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• 2003

본 시험은 스테비아 부산물의 사료적 가치를 구명하기 위하여 산란계 사료에 첨가하여 산란계의 생산성, 난 품질, 계란의 지방산에 미치는 영향을 고찰하였다. 공시계는 78주령 하이라인 360수로 강제환우후 5％ 산란시기에 시행하여 총 20주 동안 사양시험을 시행하였다. 스테비아 부산물을 산란계 사료에 0, 2, 4, 8 ％를 첨가하여 동일한 에너지(2,800 kcal/kg)와 단백질(16 ％) 수준으로 급여하였으며, 처리구당 5반복, 반복당 18수씩 총 360수를 공시하였다. 시험기간 20주 동안, 총 산란율, 난중, 산란량, 사료요구율은 스테비아 부산물 급여구와 대조구 사이에 유의적인 차이는 없었다. 스테비아 부산물의 급여가 계란의 난 품질에 미치는 영향에서 난각강도, 난각두께, 난백고 및 Haugh Unit는 대조구와 차이가 없었지만, 난황색도는 스테비아 부산물의 급여수준이 증가할수록 높은 수치를 보여 스테비아 4 ％와 8 ％ 급여구는 대조구에 비하여 유의적으로 증가하였다. 계란의 당 전이도 시험에서는 스테비아 부산물을 급여하여 생산된 계란과 대조구 사이에 차이가 없었다. 계란의 지방산 함량은 스테비아 부산물 2 ％와 4 % 급여구가 포화지방산은 감소하였고, 단가 불포화지방산은 유의적으로 증가하였다. 이러한 결과 산란계 사료에서 스테비아 부산물은 원료사료로서 8 ％까지 가능하였다.

• Korean journal of applied entomology
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• v.40 no.2
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• pp.111-115
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• 2001

Orius strigicollis Poppies is an indigenous natural enemy of thrips pests in Korea To develop an efficient mass rearing system for Ο. strigicollis, effects of hatchability, egg numbers and egg harvesting time of Ο. strigicollis were measured in cylindrical cage (251 ㎤) under the conditions of photoperiod 16L : 8D, $55\pm$10% RH and $25\pm$$2^{\circ}C$. The hatchability and developmental period of eggs were 88.5% and 5.7 days, respectively. The highest emergence rate (50.8%) was achieved when the number of eggs laid was ranged from 50 to 100 per arena. The proper harvesting time of newly produced adults was 17 days postoviposition. Relationship between the number of resulting adults per female and the number of female adults per arena was Y : -10.7971n (X) +44.659 ($R^2$=0.7619). The generation time (T), the net reproductive rate ($R_{0}$ ) and the intrinsic rate of natural increase ($r_{m}$ ) were 26.5 days, 6.18 and 0.0687, respectively.

• Korean journal of applied entomology
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• v.42 no.2
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• pp.139-144
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• 2003

The effect of $CO_2$-treatment on interrupting diapause of Bombus ignitus was examined to provide a means for year-round rearing of the bumblebee. When mated young queens were exposed to 65% or 99% $CO_2$ for 30 min daily during two consecutive days, oviposition rate increased to 75% and 77%, respectively, comparing 50% in $CO_2$-untreated queens. At the same time, the days needed to first oviposition shortened to 17-18 days in $CO_2$-treated queens, comparing to 30 days in $CO_2$-untreated queens. $CO_2$-treatment at the second day after mating was appropriate to the oviposition and colony development. $CO_2$-treatment showed a positive effect on the oviposition and colony development, but less than them of overwintered queen in numbers of produced progeny. It can be concluded that $CO_2$-treatment to B. ignitus is insufficient to produce commercial grade bumblebee colony in spite of its capability for promoting oviposition, because the treatment failed to form a big colony.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 1997.06a
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• pp.216.1-216
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• 1997

• Journal of Aquaculture
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• v.10 no.1
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• pp.63-68
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• 1997

The spawning behavior of the silurid catfish, Silurus asotus, was observed from laboratory aquaria after treating with human chorionic gonadotropin (HCG) and injection with pituitary extract of grass carp. The details of the spawning behavior presented here are based upon the observations made from 10 trials with 40 male and 20 female catfishes artificially bred between May and July, 1995. Initial spawning activity started 15 to 16 hours after injection with pituitary extract of grass carp and HCG. The activity was continued with for 2 to 3 hours and repeated mating behavior of the catfish were observed during this period. Compared to the spawning activity of the Japanese catifish, S. biwaensis, S. asotus took a different male position during the period o fsearching its partner. This study also reports some other differences in mating behavior between S. asotus and S. biwaensis.