• Title/Summary/Keyword: 연구자수

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Effects of inbreeding depression on litter size of Korean native pig (국내 품종 재래돼지 산자수에 대한 근친퇴화 효과)

  • Kim, Young-Sin;Cho, Kyu-Ho;Lee, Mi-Jin;Kim, Jeong-A;Cho, Eun-Seok;Hong, Joon-Ki
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.6
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    • pp.514-520
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    • 2019
  • The reduction in performance due to inbreeding (i.e. inbreeding depression) has long been documented in plant and animal populations. The population of Korean native pigs are small and this breed is valuable in Korea.. This study was aimed to investigate effects of inbreeding depression on total number of piglets born (TNB) and number of piglets born alive (NBA) in Korean native pigs. We used 2,806 pedigree and 303 sows's data with 483 phenotypic records. After estimating genetic parameters for each traits, inbreeding depression was estimated using a mixed model in which the inbreeding coefficient was included as a covariate. Korean native pigs had high heritability for each traits. Inbreeding coefficient constantly increased from 1998 to 2017~2018 but there is no reduction for each traits in 2017~2018 in compared with those in 1998. Significant inbreeding depression was detected for TNB (p=0.03) but not for NBA (p=0.41). In addition there are significantly positive interactions between inbreeding coefficient and breeding value for both traits (p<0.05). These results suggest that Korean native pigs are still having genetic variation for TNB and NBA, which could overcome reproductive risks from inbreeding coefficient increase.

Generation of Korean Ionospheric Total Electron Content Map Considering Differential Code Bias (Differential Code Bias를 고려한 한반도 전리층 총전자수 지도 생성)

  • Lee, Chang-Moon;Kim, Ji-Hye;Park, Kwan-Dong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.29 no.3
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    • pp.293-301
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    • 2011
  • The ionospheric delay is the largest error source in GPS positioning after the SA effect has been turned off in May, 2000. In this study, we used 44 permanent GPS stations being operated by National Geographic Information Institute (NGII) to estimate Total Electron Content (TEC) based on pseudorange measurements phase-leveled by a linear combination with carrier phases. The Differential Code Bias (DCB) of GPS satellites and receivers was estimated and applied for an accurate estimation of the TEC. To validate our estimates of DCB, changes of TEC values after DCB application were investigated. As a result, the RMS error went down by about an order of magnitude; from 35~45 to 3~4 TECU. After the DCB correction, ionospheric TEC maps were produced at a spatial resolution of $1^{\circ}{\times}1^{\circ}$. To analyze the effect of the number of sites used for map generation on the accuracy of TEC values, we tried 10, 20, 30, and 44 stations and the RMS error was computed with the Global Ionosphere Map as the truth. While the RMS error was 5.3 TECU when 10 sites are used, the error reduced to 3.9 TECU for the case of 44 stations.

데이터마이닝 기법을 이용한 이동통신 광고 전략

  • 김정숙;나종화
    • Proceedings of the Korean Association for Survey Research Conference
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    • 2001.06a
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    • pp.128-140
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    • 2001
  • 현재 국내의 이동통신 가입자수와 무선인터넷 가입자수가 급증하면서 인터넷과 이동 통신을 연계한 광고서비스나 직접 휴대폰에 광고를 제공하는 서비스가 등장하고 있다. 그러나 현재 이동통신에 제공되고 있는 광고서비스는 문자메세지를 이용하는 단문광고이고 제공되는 광고도 휴대폰 이용자가 직접 듣고 확인해야 하는 불편함을 가지고 있다. 따라서 본 연구에서는 이동통신을 활용하여 고객의 니즈(Needs)에 부합되는 광고를 제공할 수 있는 새로운 광고기법을 제안하고 이에 대한 수요예측과 데이터 마이닝 기법을 적용하여 이 광고에 대한 타겟마케팅 전략을 제시하고자 한다.

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A DETECTION STUDY OF THE IONOSPHERIC TOTAL ELECTRON CONTENTS VARIATIONS USING GPS NETWORK (GPS 기준국망을 이용한 전리층 총전자수 변화 검출 연구)

  • Choi, Byung-Kyu;Park, Jong-Uk;Lee, Sang-Jeong
    • Journal of Astronomy and Space Sciences
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    • v.24 no.4
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    • pp.269-274
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    • 2007
  • We established a regional ionospheric model for investigating ionospheric TEC (Total Electron Contents) variations over the Korean Peninsula during major geomagnetic storms. In order to monitor the ionospheric TEC variations, we used nine permanent GPS reference stations uniformly distributed in South Korea operated by the Korea Astronomy and Space Science Institute (KASI). The cubic spline smoothing (CSS) interpolation method was used to analyze the characteristics of the ionospheric TEC variations. It has been found that variations of TEC over the Korean Peninsula increase when a major geomagnetic storm occurred on November 20, 2003. The TEC has increased about one and a half of those averaged quite days at the specific time during a geomagnetic storm. It has been indicated that the KASI GPS-derived TEC has a correlation with the geomagnetic storm indices (eq. Kp and Dst indices).

Estimation of Genetic Parameters for Gestation Length, Wean to First Service, Litter Size and Stillborn Piglets in a Closed Nucleus Swine Breeding Herd (특정 종돈집단의 임신기간, 이유후초종부일, 총산자수 및 사산에 대한 유전모수 추정)

  • Lee, Deukhwan;Son, Jihyun
    • Journal of Animal Science and Technology
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    • v.55 no.5
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    • pp.389-398
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    • 2013
  • This study was conducted to investigate the genetic relationships among four reproductive traits. Data for this study were 7616 records from 1910 Landrace (L) and 10,454 records from 2283 Yorkshire (Y) in a closed nucleus swine herd. Traits considered on this study were gestation length (GL), total number of piglets born (TNB), wean to first service (WFS), and number of stillborn per litter (NSB). Heritabilities and genetic correlations were estimated by using the Bayesian inferences via Gibbs sampling in a four trait linear-threshold repeatability animal mixed model by designating NSB as a categorical trait in the L and Y purebred populations. Effects on the statistical model were considered for parity, contemporary group as fixed and service sire, permanent environmental, animal additive genetic effects as random. Estimates of heritability were 0.21, 0.23, 0.16, and 0.09 for GL, WFS, TNB, and NSB in the L population and 0.35, 0.16, 0.14 and 0.10 for corresponding traits in the Y population, respectively. Genetic correlation for GL was -0.59 and -0.28 with TNB and -0.58 and -0.17 with NSB in the L and Y populations, respectively. The NSB was positively correlated with TNB in the L and Y populations in genetic and environmental aspects. Therefore, the NSB should be taken into account in selecting sows for improving prolificacy of dam line breeding swine stock.

The Changes of Job-Housing Balance and Commuting Trip in Seoul Metropolitan Area: 2005-2010 (수도권의 직주균형과 통근통행의 변화: 2005-2010년)

  • Son, Seungho
    • Journal of the Korean Geographical Society
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    • v.49 no.3
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    • pp.390-404
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    • 2014
  • This study analysed the job-housing balance using the number of employees and workers data, and investigated the relationship between job-housing ratio and commuting trip in the Seoul metropolitan area. Between 2005-2010, in the central business district which functioned as urban center, the number of employees were reduced and population growth slowed. Meanwhile, the suburbanization of employment and population has advanced as the employment and population moved from Seoul to Gyeonggi-do. As the increasement of workers compared to the employees became prominent, the excess workers increased significantly. The size of excess workers acted as a factor which reduced the job-housing ratio. Job-housing imbalance worsened in Gyeonggi-do especially. While in many regions, job-housing imbalance improved in clerical, sales, and professional job sectors, but in some regions, the job-housing imbalance worsened in simple labor job and service job sectors. The number of jobs which job-housing imbalance was eased increased in the employment center. The more the job-housing ratio is high, the lower the degree of self-sufficiency of commuting trip and the proportion of internal commuters. In business centers where the number of employees exceed the number of workers, the job-housing ratio and the proportion of commuting trips coming from other regions showed decreasing trend together. The results bear important implications for regional labour market plans considering the spatial mismatch between jobs and housing.

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Morphological Classification of the Korean Local Corn Lines (재래종(在來種) 옥수수의 형태적(形態的) 특성(特性)에 의(依)한 분류(分類))

  • Kwon, Kyeong Hak;Choe, Bong Ho
    • Korean Journal of Agricultural Science
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    • v.13 no.1
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    • pp.1-16
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    • 1986
  • This experiment was carried out to obtain genetic information for future corn breeding. The materials used for the study were obtained from the nationwide collection of Korean local corn lines. A total of 262 lines were used for the study of morphological characters and for the classification of lines. Results obtained are summarized as follows; 1. The days to flowering of lines ranged from 57 days to 87 days. Most lines had an average of 67 days of flowering days. 2. The number of tillers of lines showed a lot of variation among lines with 49.2% of coefficient of variation. 3. The coefficients of variation computed based on the phenotypic observation or measurement of each line were 36.1%, 27.2%, 20.0%, 16.4% and 16.3% for kernel weight per ear, 100 kernel weight, ear height, plant height and ear length, respectively. 4. Ear height, ear length, ear diameter, tiller number and days to flowering were highly and positively correlation with the plant height. Kernel size, ear size, and plant height were highly correlated with 100 kernel weight and kernel weight per ear. 5. The 262 corn lines were possibly classified into four major groups by the Euclidean distance. Group I comprised 110 lines, group II 74 lines, group III 66 lines and group IV 12 lines, respectively. Group I was characterized as having early maturity, medium plant height large kernel size and large ear size. Group II had medium maturity, short plant height, medium kernel size and small ear size. Group III had medium maturity, medium plant height, large kernel size and medium ear size. Group IV had late maturity, long plant height, small kernel size, small ear size and many tillering. 6. The plant height showed significant difference between group I and II, II and III, and II and IV group. No statistical differences were observed between group III and IV. The ear size of group I was significantly different from those of group II, III and IV. Also difference of ear size between group II and III was significant. The kernel size, 100 kernel weight and kernel weight per ear were all significantly different among all groups classified. The row number was different between group I and II. The row number of lines in group IV was significantly different with group I, II, III respectively. The number of tillers and flowering days of lines in group IV were greatly different from those of group I, II and III. 7. The corn lines collected from northwest plain regions and middle hilly regions in Korea had medium maturity, medium plant height, large ear and large kernels. The corn lines from middle eastern hilly regions had medium size of ear kernels. The corn lines from middle southern hilly regions had late maturity, small kernel size and many tillers. The corn lines from southwest plain areas had late maturity, long plant height and many tillers.

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The ornaments modeling applied of amethyst gems and design development of interior jewel modeling (자수정(Amethyst) 보석을 응용한 장신구 조형과 Interior Jewel Modeling의 디자인 개발)

  • Kim, Eun-Ju
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.22 no.4
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    • pp.170-177
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    • 2012
  • Amethyst gems represents thermal effects of far-infrared emission, promotes the body's metabolism, and attracts attention as an eco-friendly interior material. In this paper, amethyst increase the value of jeweling by applying the characteristic purple motif, furthermore, I will intend to develop of design model. Metal crafting of brooch & necklace in the works performed based on the organic three-dimensional shape of the Rhino CAD Data. It was made possible through the precise laminated wax processing and then combining the amethyst. I researched the ornament modeling by applying the 'Golden Ratio', and suggesting utilizing method for interior jewel modeling, and also, is expected that this paper on the amethyst modeling design can contribute to the manufacturers' productivity.

A Study on Modern Applicability of Traditional Korean Embroidery Technique (한국전통자수기법의 현대적 활용에 관한 연구)

  • Lee, Mi Seok;Kim, Chung Ho
    • Journal of the Korean Society of Costume
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    • v.64 no.7
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    • pp.45-56
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    • 2014
  • Embroidery is called 'Ja-Su' in Korea. The purpose of this study is to present a method that utilizes the technology of traditional Korean embroidery to get a genuine feeling of tradition. This study was conducted in the following manner: first, Previous researches and references were used survey traditional embroidery techniques. Second, by using traditional embroidery techniques, the study attempted to develop a design of embroidery household Items with modern sense and practicality. The results of this study are as follows: This study has developed and produced embroidery household items that can be used in modern life by using traditional embroidery techniques. A total of 10 kinds of miscellaneous everyday life utensils and interior pieces were produced. Materials used in the embroidery production were made out of natural fabrics, such as cotton (Kwang-Mok, Mu-Myung), linen, cotton thread were used for a practical reason for practical reasons (i.e. being easily washable). Embroidery techniques used in this study were straight stitch, outline stitch, satin stitch, separate stitch, french knot stitch, long&short stitch, brick stitch, chain stitch, couching stitch, Pad stitch, and pine-leaf stitch. In order to further develop traditional embroidery, a technique passed down from the ancestors, it needs to change to become more suitable for modern life while maintaining the tradition.

Estimation of Fatality Reduction by Introducing Technical Regulation on Pedestrian Protection (보행자 충돌안전기준 도입에 따른 사망자수 감소 효과 추정)

  • Oh, Cheol;Kang, Youn-Soo;Kim, Won-Kyu;Kim, Beom-Il
    • Journal of Korean Society of Transportation
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    • v.23 no.3 s.81
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    • pp.49-57
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    • 2005
  • This study developed a methodology for estimating the fatality reduction by introducing technical regulation on pedestrian protection in pedestrian-vehicle collisions. Modeling a probabilistic pedestrian fatality model with logistic regression approach was one of keen interests, which employed in estimating the fatality reduction. Collision speed obtained from the accident reconstruction was used in the model development. The effects of fatality reduction, in case various Head Injury Criterion (HIC) and collision speeds are applied for the regulation. were presented as the major outcome of this study. It is expected that the outcome of this study would be an invaluable tool to assist in developing various technologies and policies for pedestrian protection.