• 대한기계학회논문집A
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• 제30권12호
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• pp.1603-1610
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• 2006

In this paper compressive characteristics of composite egg-box panels were investigated and energy absorption was calculated from the nominal stress-strain relations obtained by the compressive tests. Several different stacking sequences and number of plies were introduced for investigation of static compression characteristics and the energy absorption rates of composite egg-box panels. The compressive stress-strain relation and energy absorption of various composite egg-box panels were compared with those of aluminium egg-box panels. From the test results it was found that the fracture behavior of composite egg-box panel was affected by stacking angle causing different local deformation, during lay-up and draping processes and types of prepreg; that is, plain weave carbon/epoxy and 4-harness satin glass/epoxy. The energy absorption capacity of composite egg-box panels were proved to be higher than that of aluminium egg-box panels with low mass.

• 한국응용곤충학회지
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• 제19권2호
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• pp.109-112
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• 1980

본답후기인 8중-9상순에 걸쳐 끝동매미충 난에 기생하는 기생봉의 종류와 이들의 기생율을 남부 4개 지역에서 재래품종과 통일계통 품종 포장에서 조사한 결과는 다음과 같다. 1. 난에 기생하는 실적으로 Gonatocerus sp. 2종과 Paracentrobia andoi 그리고 Anagrus sp. 1종 등 모두 4종의 난기생봉이 분포하고 있음이 밝혀졌다. 2. 기생율 조사 결과 Gonatocerus sp.의 평균 난괴기생율과 난립기생율은 각각 $58.8\%$와 $41.0\%$였고 Paracentrobia andoi의 경우에는 각각 $6.2\%$와 $5.3\%$로서 Gonatocerus sp.가 Paracentrobia andoi의 기생율 보다 훨씬 높안 우점종을 이루어 있었으며 이들 두 종이 같은 난괴에 혼재하는 율은 $5.4\%$였다.

• 한국응용곤충학회지
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• 제41권3호
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• pp.225-231
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• 2002

곤충병원성 선충인 Steinernema carpocapsae All (ScA)과 포천(ScP) 계통, S.glaseri NC (SgN)와 동래(SgD) 계통, Heterorhabditis bacteriophora NC 1 계통(HbN)이 당근뿌리혹선충 (Meloidogyne hapla)의 난낭 형성에 미치는 영향을 구명하기 위하여 토마토를 이용한 pot실험을 수행한 결과는 다음과 같다. 450마리의 당근뿌리혹선충이 있는 100g 토양에 곤충병원성 선충을 2.5$\times$$10^{5}$ 마리 농도로 처리한 결과 ScA처리에서 9.4-36.5개, SgN처리에서 5.7-24.7개, HbN처리에서 11.2-16.0개로서 당근뿌리혹선충 단독 처리에서의 62.5개보다 난낭수가 매우 적었다. Steinernema선충을 100㎤당 100마리, 200마리의 당근뿌리혹선충에 대해 2,020마리/토양 350g와 1.6$\times$$10^{5}$ 마리 농도로 처리한 결과 Steinernema 선충의 종간, 계통별 또는 처리농도 간에는 난낭수의 차이가 없었으나, 당근뿌리혹선충 단독 처리와 비교하면 난낭수가 현저히 감소하였다 곤충병원성 선충을 당근뿌리혹선충 처리 3일 전에 처리한 것이 3일 후에 처리한 것보다 난낭 형성 억제에 더 효과적이었다. 한편, 곤충병원성 선충은 토마토의 생육에 아무런 영향을 끼치지 않았다.

• 한국양식학회지
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• 제9권4호
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• pp.345-351
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• 1996

한국산 B. plicatilis, L-type rotifer와 S-type rotifer의 내구란 대량생산은 L-type rotifer의 경우 15일 동안 농축 Chlorella + 빵효모 혼합구와 빵효모 단독구로 하였고 S-type rotifer는 7일동안 1 $m^3$ 수조에서 농축 Chlorella로, $6{\~}8$일 동안 4 $m^3$ 수조에서 냉동 농축 Chlorella + 빵효모로 대량생산하였다. L-type rotifer 내구란 대량생산 실험에서 농축 Chlorella + 빵효모 혼합구가 총 내구란 생산 $54.5{\times}10^6$개, $10^{8}$ rotifers 당 내구란 생산 $30.5{\times}10^6$개, 먹이 건조 중량 1g 당 내구란 생산 $100{\times}10^3$개로 빵효모 단독구 보다 높게 나타났다. S-type rotifer의 내구란 대량생산은 4 $m^3$ 수조에서 냉동 농축 Chlorella + 빵효모를 먹이로 총 내구란 생산 $149{\~}567{\times}10^6$개, $10^{8}$ rotifers당 내구란 생산 $36{\~}123{\times}10^6$개, 먹이 건조 중량 1 g당 내구란 생산 $131{\~}338{\times}10^3$개를 생산하여 1 $m^3$ 수조에서 농축 Chlorella를 단독 먹이로 생산한 경우 보다 높았다.

• 한국수산과학회지
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• 제54권1호
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• pp.31-37
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• 2021

The mass production of fertilized eggs of the convict grouper Hyporthodus septemfasciatus was studied from 2013 to 2020 for industrial aquaculture. The experiment was divided into two groups. Group 1 broodstock was raised from wild-caught fry and used from 2013 to 2020. Group 2 broodstock was raised from artificially propagated fry and used from 2019 to 2020. Males used to collect sperm for artificial insemination weighed more than 7 kg. The effects of various hormones on artificial ovulation were investigated from 2013 onward. Among these, luteinizing hormone-releasing hormone analogue (LHRHa) at 100 ㎍/kg body weight showed the most effective results and was used for artificial egg collection from 2014 onward. In Group 1, the average total egg production per year, average egg production per individual, fertilization rate, and hatching rate were 26,143 mL, 609.7 mL, 93.3%, and 91.8%, respectively, and in Group 2, were 2,750 mL, 316.5 mL, 92.1%, and 90.4%, respectively. Based on these results, we showed that a large number of fertilized eggs for artificial seeding could be produced consistently. Moreover, the mass production of fertilized eggs in Group 2 establishes a foundation for the complete aquaculture cycle of H. septemfasciatus.

• International Journal of Industrial Entomology and Biomaterials
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• 제46권2호
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• pp.55-59
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• 2023

One of the necessary conditions for the mass production of the edible insect, the white-spotted flower chafer Protaetia brevitarsis seulensis (Kolbe), is to breed a strain with excellent egg-laying ability. To identify external morphological traits related to egg-laying ability, we investigated the effects of the weight, length, and width of female adults on egg production. Correlation and multiple regression analyses revealed a positive correlation between the weight of female adults and egg production. This study suggests that selection of heavier females is a good strategy for breeding strains with superior egg-laying characteristics. The results of this study will serve as important foundational data for future breeding of superior strains.

• Asian-Australasian Journal of Animal Sciences
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• 제17권4호
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• pp.518-522
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• 2004

This experiment was conducted to investigate the effects of different levels of dried leftover food (DLF) in the diet on feed utilization and egg-laying performance of hens. One hundred sixty-eight, 18 week old Tetra brown commercial layers, were assigned to 7 treatments in a completely randomized design. Each treatment has four replications per treatment with six animals per replication. All the experimental animals were fed diets for 7 weeks. The treatments included 1) control group without DLF, 2) diet with 10% DLF, 3) diet with 20% DLF, 4) diet with 30% DLF, 5) 10% higher protein level of diet with 10% DLF, 6) 20% higher protein level of diet with 20% DLF and 7) 30% higher protein level of diet with 30% DLF. Average daily feed intake (ADFI) tended to be improved with DLF feeding. ADFI of group fed diets with 20% was significantly higher than that of control (p<0.05). Feed conversions of DLFfed groups were higher than that of control. Egg production tended to be higher in groups fed diets with 10% DLF than control diet without significant differences (p>0.05). However, those of groups fed diets containing 20 and 30% DLF were lower than that of control. Supplementing protein source to DLF-containing diets improved egg production (p<0.05). Increasing level of DLF in the diet for layer decreased egg weight and egg mass compared to control without significant differences (p>0.05). Protein supplementation to DLF-containing diets increased egg mass without significant difference (p>0.05). The range of egg cholesterol concentration of DLF-fed groups was 11.94-14.10 mg/g while that of control group was 12.31 mg/g although there was no significant difference among treatments (p>0.05).

• Animal Bioscience
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• 제34권5호
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• pp.886-894
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• 2021

Objective: An experiment was conducted to study the effect of graded concentration of digestible lysine (dLys) on performance of layers fed diets containing sub-optimal level of protein. Methods: Five diets were formulated to contain graded concentrations of dLys (0.700%, 0.665%, 0.630%, 0.593%, and 0.563%), but similar levels of crude protein (15% CP), energy (10.25 MJ ME/kg) and other nutrients. A total of 3,520 hens (26 wk of age) with mean body weight of 1,215+12.65 g were randomly divided into 40 replicate groups of 88 birds in each and housed in an open sided colony cage house. Each diet was offered ad libitum to eight replicates from 27 to 74 wk of age. The performance was compiled at every 28 d and the data for each parameter were grouped into three phases, that is early laying phase (27 to 38 wk), mid laying phase (39 to 58 wk), and late laying phase (59 to 74 wk of age) for statistical analysis. Results: Egg production, egg mass and feed efficiency (feed required to produce an egg) were significantly improved by the dLys level during the early and mid laying phases but not during the late phase. Whereas feed intake was significantly reduced by dLys concentration during mid and late laying phases but not during early laying phase. The egg weight was not affected by dLys concentration in any of the three phases. Conclusion: Based on best fitted statistical models, dietary requirements of dLys worked out to be 0.685%, 0.640%, and 0.586% during early phase, mid phase, and late egg laying phase, respectively. The calculated requirement of dLys for the respective production phases are 727 mg/b/d during the early and mid laying phases and 684 mg/b/d during the late laying phase in diets containing 15% CP.

• Asian-Australasian Journal of Animal Sciences
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• 제16권12호
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• pp.1799-1803
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• 2003

The possibility of lycopene affecting egg yolk pigmentation was studied with lycopene diets containing 0, 4, 8, and $12{\mu}g/g$ meal, respectively. The addition of lycopene above $4{\mu}g/g$ meal significantly improved yolk color after four days of supplementation. The transfer of lycopene into egg yolk was confirmed by thin layer chromatography, and high-performance liquid chromatography-mass spectrometry (HPLC-MS). The deposition rate of lycopene into egg yolk was approximately 2%, which was quantitatively determined using a HPLC with a UV detector. The result indicates that lycopene is a good candidate for egg yolk pigmentation and for making functional eggs.

• 한국가금학회:학술대회논문집
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• 한국가금학회 2000년도 제17차 정기총회 및 학술발표
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• pp.70-72
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• 2000

The Effects of Dietary Supplemental Charcoal Extract (CE) were examined on performance of 19-week-old ISA Brown hens for 12weeks. Four hundred and fifty were randolmy assigned to 0, 0.025, 0.05, 0.075, 0.1% dietary CE, respectively with five replicates of 18 hens per pen. Basal diets contained 17.5% CP and 2,800 ME. Egg production egg weight, feed conversion(FC), and egg qualities were measured in every four weeks. Egg production and FC was slightly improved in 0.05% supplemental CE group compared to that of other treatments, but was not signhificant different. Average egg weight was significantly higher in 0.025% and 0.1% than other treatments(P<0.05). Total egg mass tended to be higher in 0.05% supplementation. Daily feed intake increased in 0.1% supplementation than the others, but was not statistically different. Eggshell breaking strength and Haugh unit were tended to be higher in 0.05% supplementation. There were no significant difference in eggshell thickness and yolk color of all treatments.