• Proceedings of the Korean Society of Fisheries Technology Conference
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• 한국어업기술학회 2003년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.341-342
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• 2003

쥐노래미는 쥐노래미과에 속하는 연안정착성 동계산란어종으로 우리나라 전연안과 중국, 일본에 서식하고 있다. 최근 무분별한 남획으로 인하여 자원량이 급감되어 쥐노래미는 일찍부터 양식대상종으로 각광을 받아왔다. 지금까지 쥐노래미과에 관한 연구ㆍ보고된 것은 정과김(1994)에 의한 노래미의 성숙과 산란이 보고되어 있을뿐 쥐노래미의 성성숙과 산란에 관한 연구는 찾아보기 어렵다. (중략)

• Korean Journal of Environmental Biology
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• 제40권3호
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• pp.281-289
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• 2022

The effect of five different constant temperatures (18, 21, 24, 27, and 30±1℃) and a photoperiod of 14 : 10 (L :D) h on the reproduction parameters of Spodoptera frugiperda was studied. The longevity of adult female S. frugiperda decreased with increasing temperature (22.4 days at 21℃ and 13.9 days at 30℃) but not at 18℃. The pre-oviposition period and oviposition period was the shortest at 30℃ compared to the other temperatures. The total fecundity egg count was 887.4, 1,246.4, 1,348.9, 1,154.9, and 1,034.2 at 18, 21, 24, 27 and 30℃, respectively, during its life span. The survival rate of female S. frugiperda decreased rapidly after 13 days at 18℃, after 14 days at 21℃, after 15 days at 27℃, and after 9 days at 24℃, and 30℃. On the third day after the start of oviposition, 50% of the total fecundity was accomplished. In corn fields at less than the 10-leaf stage, the distribution of S. frugiperda egg masses was observed in the middle and lower plant regions, corresponding to 46.8% and 41.4% of the total egg masses, respectively. Egg masses were mostly found on the underside of the leaf blade (abaxial) of corn(66.7%). After releasing S. frugiperda adults on May 12, May 17, May 25, and May 30, the number of eggs per egg mass was 89.9, 88.5, 126.6, and 127.9, respectively. Egg masses of the subsequent generations of S. frugiperda were observed from late June, and the number of eggs per egg mass was 155.8 in late June, 270.7 in early July, and 303.5 in mid-July.

• KOREAN POULTRY JOURNAL
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• 제40권10호
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• pp.136-139
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• 2008

본고에 저자는 식품으로써 활용가치가 떨어지고 있는 산란노계육의 활용 증진을위해 계육수리미 생산 및 식육푸레이크 생산에 대해서 소개를 한 바 있다. 이번호에서는 산란노계육의 활용을 위한 세 번째 방안으로써 축산과학원에서 수행되었던 과제의 일부 결과물에 대해 소개를 하고자 한다.

• Korean Journal of Ichthyology
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• 제35권4호
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• pp.333-339
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• 2023

The aim of this study was to collect information regarding the sex ratio, size at sexual maturity, and the primary spawning period of Hexagrammos otakii. The sex ratio (female : male) was observed to be 1 : 1.2 (n =739 : 906, with females comprising 81.6% of the population). The gonadosomatic index (GSI) exhibited its highest values in November for females and October for males, coinciding with the primary spawning period from November to January. The total length required for 50% sexual maturity was determined through a logistic regression model and found to be 23.1 cm for females.

• Transactions of the Korean Society of Mechanical Engineers B
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• 제32권11호
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• pp.878-883
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• 2008

The spray characteristics of a high pressure 6-hole injector were examined in a single cylinder optical direct injection spark ignition (DISI) engine. The effects of injection timing, in-cylinder charge motion, fuel injection pressure and coolant temperature were investigated using the 2-dimensional Mie scattering technique. It was confirmed that the in-cylinder charge motion played a major role in the fuel spray distribution during the induction stroke while the propagation of fuel spray was restrained during the compression stroke by the increasing pressure and the upward moving piston. In additions, it was confirmed that the liquid fuel droplets existing at the sprays edges were vaporized by the increase of the coolant temperature.

• KOREAN POULTRY JOURNAL
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• 제50권7호
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• pp.142-144
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• 2018

• Korean Journal of Fisheries and Aquatic Sciences
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• 제15권4호
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• pp.345-358
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• 1982

1980.8-1982.8월까지 일광, 주문진, 돌산, 어청도 및 성산포에서 채집한 1,663미의 보라성게의 성장 및 산란에 관한 조사이다. 1세부터 5세까지의 평균각경은 가각 19, 32, 43, 51, 58mm로 추정됐으며 $l_\infty=84.4 mm,\;k=0.223,\;t_o=-0.187$의 성장식을 보였다. 가경에 대한 각고, 보대, 간보대, 위홍문부경 및 극 길이의 상관관계는 매우 높았다. 연령에 따른 가부분의 상대성장은차이가 없으나 극의 성장에서는 3세까지는 각경에 비례하여 성장하나 그 이후의 연령부터는 반비례하고 있다. 일광해역에서의 산란은 6-10월에 일어나며 주 산란은 8월로 사료한다. 연령에 따른 주 산란시기는 다르며 고연령군은 저연령군 보다 일찍 산란하고 있다. 제주산 보라성게는 8월 이전에 산란을 이미 마친 상태이며 여수산, 일광산은 주로 8월에, 주문진산, 어청도산은 8월 이후에 산란하는 것으로 판단된다.

• Korean Journal of Ichthyology
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• 제28권2호
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• pp.93-99
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• 2016

Spawning period and spawning characteristics of Kichulchoia multifasciata (Pisces: Cobitidae) inhabiting the Yugokcheon (stream) of Nakdonggang (river) were investigated in the area of Segangyo (bridge), Yugok-myeon, Uiryeng-gun, Gyeongsannam-do, Korea from November 2008 to October 2009. The total length of population indicated that 45~55 mm group is one year old, 55~75 mm group is two years old and longer than 75 mm is regarded over three years old in males and 40~55 mm group is one year old, 55~75 mm group is two years old, 75~95 mm group is three years old and longer than 95 mm is considered over four years old in females (January 2009). It has predicted that the spawning period is from May to June (water temperature in the range $21.0{\sim}26.6^{\circ}C$). Sexually matured individuals appeared over the two years old. The number of eggs in the ovaries was 202~747 ($491{\pm}154.0$).

• Korean Journal of Environmental Biology
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• 제40권2호
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• pp.187-198
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• 2022

In this study, Telenomus remus Nixon (Hymenoptera: Scelionidae) was first reported as a natural enemy of the fall armyworm Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) egg collected from corn fields in Korea, and its biological characteristics was studied. Based on morphological and molecular analysis, the parasitoid emerged from S. frugiperda eggs was identified as T. remus. We found that T. remus can attack the eggs of S. frugiperda, Spodoptera litra and Spodoptera exigua under a laboratory condition. The longevity of T. remus female adult was longer than that of male adult. The egg-to-adult period of T. remus was not affected by the host age and sex. T. remus female adult laid at least 1-3 eggs a day to a maximum of 37 or more eggs, and the most oviposited on the 3^rd to 4^th day after emergence. The host preference for oviposition of T. remus adult was high in the order of S. litura>S. exigua>S. frugiperda. T. remus preferred to parasitize 1- and 2-day-old host egg rather than 3-day-old host egg. When compared to the sex ratio of T. remus progeny, the rate of female progeny was higher at the initiation time of oviposition, while the proportion of male progeny increased significantly with female adult age, especially after 8-day-old adult. This information may be useful for improving T. remus mass rearing system and developing a biological control program to control S. frugiperda.

• Korean Journal of Fisheries and Aquatic Sciences
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• 제9권4호
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• pp.251-255
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• 1976

Three hundred and sixty two specimens of Plecoglossus altivelis were randomly sampled from Chunji Stream in Seogwipo, Cheju-Do, during the period from 25 Aug., 1973 to 14 Feb., 1974 to investigate the relationship between total length and dody weight as well as the condition factor during the spawning period. Results obtained are summarized as follows : The relationships between total length and body weight are calculated as below, respectively : $W=0.008639\;L^{3.1806}$ : Prior to spawning period $W=0.01830\;L^{2.7689}$ : During spawning period The above equations differ each other significantly. Nevertheless, the significant difference is not found between sexes. The mean body length decreased during the spawning season. The fact seems to be caused by the death of large fish after spawning. The condition factor was $13.45\%_{\circ}$ on the average in August. The value decreased continuously from September, giving the minimum mean value of $10.25\%_{\circ}$ on Nobember 29. But the value increased again, showing $11.18\%_{\circ}$ in next February. Majority of the fish survived until next year was small ranging from 11 to 12cm in total length.