• The Korea Swine Journal
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• v.21 no.8 s.240
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• pp.80-83
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• 1999

양돈관리에 있어 생산성을 극대화하기 위한 방안을 살펴보면 첫째가 기록관리를 통한 생산성 분석, 둘째는 총산자수 향상을 위한 교배기술, 셋째는 효율적인 주간관리, 넷째는 임신진단을 통한 불임돈의 조기색출, 다섯째는 초산돈 관리와 분만후 5일 이내 자돈의 집중관리가 그것이다. 이 부분에서 총자산수 향상을 위한 교배기술은 무엇보다 중요하다. 특히 모돈에 있어서 이유후 재귀발정의 시기와 강도는 임신에 크나 큰 영향을 미친다. 다음에서 후보돈관리와 모돈관리, 웅돈관리 요령을 살펴보겠다.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.32 no.2
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• pp.196-200
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• 1987

유채박의 사료화를 위한 성분개량을 목표한 육종의 기초자료를 얻고자 유채박의 OZT함량이 낮은 영산유채와 그 함량이 고함유인 품종들을 정역교배하여 얻은 F$_2$세대의 종실을 대상으로 OZT함량에 관여하는 유전자수와 세포질의 영향에 관하여 조사분석한 결과는 다음과 같다. 1. F$_2$세대에서 OZT함양을 영산유채에 기준한 낮은 개체의 출현율은 OZT함량이 저함유인 품종을 모본으로 교배한 조합에서 높게 나타났다. 2. OZT함량의 분리비는 63 : 1에 가장 적중도가 높아 3쌍의 열성유전자가 OZT생성에 관여하고 있는 것으로 추정되었다. 3. OZT함량의 유전에 세포질의 영향이 인정되었다.

• Korean Journal of Poultry Science
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• v.45 no.2
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• pp.125-135
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• 2018

This study was conducted to evaluate the productivity and meat quality of three newly-developed crossbreds of Korean native chicken (2A, 2C, and 2D) as compared with commercial Korean native chicken (CKNC) and commercial broiler. Totally, 400 birds of different crossbreds were randomly allotted to eight pens, each with 50 birds. The birds were reared ad libitum and slaughtered at the age of 12 weeks. Fifty male chickens were slaughtered at the same day in the same slaughterhouse were selected for the comparison of meat quality. The crossbred 2C had greater body weight than that of CKNC (P<0.05), and had similar uniformity with lower death rate. Although shank length of 2C was the longest among the Korean native chicken breeds, the ratio of shank length to body weight was the lowest among them (P<0.05). The crossbred 2C had similar inosine 5'-monophosphate (IMP) content as that of CKNC in breast meat, and the highest IMP content in thigh meat (P<0.05). In a sensory analysis, the crossbred 2C generally showed, similar savory taste and texture as that of CKNC, and the overall acceptability of thigh meat was the highest in CKNC and broiler. Based on the present results, the possibility of commercialization of a newly-developed crossbred of Korean native chicken was confirmed.

• Korean Journal of Poultry Science
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• v.50 no.3
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• pp.133-141
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• 2023

We conducted a 5 × 5 diallel cross-combination test using 1,060 chickens from pure lines of Korean Rhode-C, -D, Korean Leghorn-F, -K, and Korean Native Yellowish-brown chicken (KNC-Y) to develop a new Korean native chicken layer breeder. The laying performance and combining ability, including livability, body weight, age of first egg-laying, hen-day egg production, and egg weight, were analyzed. The livability from birth to 48 weeks was 72.1±24.0%, with the highest observed in the YC and the lowest in the DK combination (P<0.01). The YC combination exhibited the highest general combining ability (GCA), while the YD combination showed the highest specific combining ability (SCA). Regarding body weight, combinations involving Leghorn showed lighter weights compared to combinations with Rhode and KNC-Y (P<0.01). Additionally, the offspring from the KNC-Y combination reached sexual maturity earlier than those from the Rhode combination. The hen-day egg production was 70.7±12.0%, with the highest seen in the CK combination at 86% (P<0.01). The effects of GCA and SCA on hen-day egg production were similar, with the SCA being highest in the YD combination and the GCA being highest in the Rhode-C. Significant differences in egg weight were observed among the combinations, with the eggs from Rhode and Leghorn combinations being heavier than those from combinations with KNC-Y (P<0.01). In conclusion, the YC and YD combinations, characterized by excellent livability, are highly desirable paternal strains, while the CF and CK combinations, with excellent laying performance and moderate egg weight, are preferred maternal strains for Korean native chicken layer breeders.

• Korean Journal of Poultry Science
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• v.41 no.1
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• pp.39-44
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• 2014

The goal of this study was to evaluate the growth performance of crossbred strains using Korean native chicken (KNC). The data were collected from 2012 through 2013 at Poultry Science Division, National Institute of Animal Science, Korea. The number of chicks analyzed in this study was 375. Crossbred were (A) $R{\times}S$, (B) $D{\times}H$, (C) $D{\times}S$, (D) $C{\times}Y$ and (E) $Y{\times}H$. The fertility rates of strains were 94.9% in crossbred A, 91.9% in crossbred B, 91.8% in crossbred C, 89.7% in crossbred D and 93.8% in crossbred E, respectively. The fertility was highest in crossbred A, but crossbred C showed the lowest (p<0.05) based on the hatchability. The crossbreds B and C exhibited a superior performance on body weight gains during growing stages but crossbred D showed the lowest (p<0.05). The feed intake was to the pattern of body weight. The feed intake of crossbred D was significantly lower than other crossbreds. Also, feed conversion ratio of crossbred D showed the lowest (p<0.05). Egg production ratio of crossbred D was significantly higher compared to the other crossbreds. These results suggest that the development of new crossbreds of commercial Korean Native Chickens should be required for better performance.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.3
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• pp.54-59
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• 2005

The cylindrical object are widely used as mechanical parts in the manufacturing process. In order to handling those objects using a robot or an automated machine automatically, the pose of the object must be known. The pose can be described by two rotation angles; one angle about the x axis and the other about the y axis. In the many previous researches these angles were obtained by the computationally intensive algorithm, that is, fitting the data as a polynomial and doing pseudo inverse. So that, this method required high performance microprocessor. In this paper in order to avoid complex computation, a new method based on a genetic algorithm is proposed and analyzed through a series of simulations. This algorithm utilized the geometry of the cylindrical shape. The simulation results show that this method find the pose angles very well In most cases, but the computation time is randomly changed because the genetic algorithm is basically one of the random search method.

• Journal of Life Science
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• v.17 no.11
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• pp.1477-1481
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• 2007

The mating systems of natural populations of Vicia tetrasperm in Korea were determined using allozyme analysis. The result suggests that V. tetrasperm is low rates of outcrossing or mix-mating outcrossing (self-fertilization, s < 0.5). At the population levels, the values of inbreeding coefficient of ten populations in Korea varied from 0.131 to 0.176, giving an average 0.154. For ten natural populations, multi-locus estimates of outcrossing (tm) was 0.333 across fifteen polymorphic loci, with individual population values ranging from 0.269 to 0.423. The differences between the tm and ts values were not close to zero (tm - ts > 0.154), indicating that biparental inbreeding was significant in the loci. The reason for relatively low outcrossing rates of some populations could be attributed to extensive consanguineous mating and isolation of flowering mature plants. Although heterozygote excess was observed in one natural population, most populations exhibited varying degrees of inbreeding and heterozygotes deficit. Thus, selection against homozygotes operated in the progeny populations throughout the life cycle.

• Journal of Sericultural and Entomological Science
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• v.31 no.1
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• pp.20-24
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• 1989

The purpose of this experiment was to obtain the basic information on heterosis and inbreeding depression of quantitative characters in the silkworm by diallel crosses of seven varieties differing widely in each character. Period of 5th instar cocoon weight, cocoon layer weight, cocoon layer ratio, boiling off ratio, raw silk percent, bave length, bave weight, bave size, weight of first molting larva and fourth molting larva were investigated. The results obtained were summarized as follows : The degrees of positive heterosis of cocoon weight and cocoon layer weight were higher. Period of 5th instar and boiling off ratio were negative heterosis. In F1 generation, cocoon weight and bave weight showed positive heterobeltiosis, while fifth instar-period, cocoon layer ratio and boiling off ratio showed negative heterobeltiosis in the F1 and F2 generation. Inbreeding depression was observed in cocoon layer ratio and boiling off ratio.

• The Korean Journal of Mycology
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• v.31 no.2
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• pp.98-102
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• 2003

Metalaxyl sensitivity related with distribution feature of mating type was characterized far Phytophthora capsici population, totally 433 isolates of the red-pepper pathogen collected from 75 pepper fields in Korea from 1995 to 1998. At the concentration of metalaxyl $2{\mu}g/ml$, inhibition rate of mycelial growth of P. capsici isolates was 68.2% in average compared to control, and 28.6% isolates in average were estimated as resistance to the chemical. Isolates of field unit with a single mating type revealed similar level of sensitivity to metalaxyl and showed sensitive or resistant in most field units. However, isolates of field units with both mating types revealed diverse sensitivity level to the chemical and various occurrence ratio of metalaxyl sensitive : resistant in each field unit. Results indicated that different levels of metalaxyl sensitivity of P. capsici population in Korea seem to be closely related with occurrence ratio of A1 : A2 mating type of each field.

• FLOWER RESEARCH JOURNAL
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• v.16 no.2
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• pp.118-123
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• 2008

For effective production of interspecific hybrids of Lilium and valuable new cultivars, we used Lilium Asiatic hybrid 'Tiny Ghost' as the female parent, and Oriental group, and Longiflorum group and Martagon as the male parents. Percentage pollen germination in Oriental hybrid 'Sorbonne' was the highest with 64%. As results of using normal style pollination and cut style pollination methods, all seed sets were formed in normal style pollinated treatment, except in 'Aktiva'. Pollen germination percent of Longiflorum hybrid 'Norina' was higher than that 'Gelria'. However, all crossings using 'Norina' failed to set seeds. Corresponding fertilization ratio was different from genetic compatibility, even in the same group. From the crossing using 'Aktiva' as the male parent one bulb was obtained derived from one embryo sac. And using 'Sorbonne' as the male parent, one plantlet was obtained after four ovule cultures. Crossing using 'Gelria' as the male parent five embryos, 15 embryo sacs, and seven ovules per one ovary were obtained. Among them, 18 plantlets germinated, with the germination percent of 66.7%. Crossings using L. hansonii, Martagon group, as the male parent resulted in 40% germination from five ovules.