회전목마 : 해외위업선에서의 혼승문제에 관하여

이득환 한국해사문제연구소 1988 (月刊)海洋韓國 Vol.181 No.-

임의회귀 검정일 모형을 이용한 홀스타인 젖소의 1산차 산유형질 및 체세포지수에 대한 유전모수

이득환,조주현,한광진 한국동물자원과학회 2003 한국축산학회지 Vol.45 No.5

The objective of this study was to estimate genetic parameters for test-day milk production and somatic cell score using field data collected by dairy herd improvements program in Korea. Random regression animal models were applied to estimate genetic variances for milk production and somatic cell score. Heritabilities for milk yields, fat percentage, protein percentage, solid-not-fat percentage, and somatic cell score from test day records of 5,796 first lactation Holstein cows were estimated by REML algorithm in single trait random regression test-day animal models. For these analyses, Legendre polynomial covariate function was applied to model the fixed effect of age-season, the additive genetic effect and the permanent environment effect as random. Homogeneous residual variance was assumed to be equal throughout lactation. Heritabilities as a function of time were calculated from curve parameters from univariate analyses. Heritability estimates for milk yields were in range of 0.13 to 0.29 throughout first lactation. Heritability estimates for fat percentage, protein percentage and solid-not-fat percentage were withing 0.09 to 0.11, 0.12 to 0.19 and 0.17 to 0.23, respectively. For somatic cell score, heritabilities were within 0.02 to 0.04. Heritabilities for milk productions and somatic cell score were fluctuated by days in milk with comparing 305d milk production.

초음파측정 활용 고급육형 한우개량을 위한 선발반응 Monte Carlo 모의실험

이득환 한국동물자원과학회 2003 한국축산학회지 Vol.45 No.3

고급육형 한우개량을 위하여 현행 실시하고 있는 한우 후대검정에서 조사되는 배장근단면적, 등지방두께 및 근내지방도 등에 대한 유전적 개량량과 초음파 측정장치를 이용한 해당 형질들의 육질판정자료에 의한 간접선발시 유전적 개량량을 모의실험을 통하여 추정하고 상호 그 효율성을 비교하였다. 본 연구에 적용된 Monte Carlo 묘의실험은 각 설정 모형별, 표현형 선발 및 다형질 BLUP 추정방법에 의한 육종가 추정치에 의한 선발을 적용하여 각각 10반복씩 반복 실험하였다. 각 모형별 모의실험 방법은 종축집단의 크기 및 세대 수 그리고 설정모형을 동일하게 설계하였으며 수컷 100두와 암컷 2,000두의 기초집단으로부터 매 세대 수컷 20두와 암컷 1,000두를 3가지 형질에 동일한 가중치를 두어 10세대 동안 선발하였다. 최종 생성된 자료를 이용하여 유전적 개량량을 추정하였고 이를 각 모형별, 선발방법별로 비교, 분석하였다. 분석결과 현행 실시하고 있는 한우 후대검정과 유사한 모의실험에서의 각 형질별 육종가 추정치에 의한 선발시 유전적 개량량과 비교한 결고, 초음파 측정치와 도축 실측치 간의 유전상관을 0.81~0.97으로 가정하고 암, 수 모두 초음파 측정자료를 조사한다는 가정으로 초음파 측정치의 육종가에 의한 선발을 실시할 때, 1.66~2.44 배의 개량 효율성이 있는 것으로 추정되었으며 이들 상관을 0.63~0.68으로 가정한 모의실험에서는 1.18~20.8 배의 개량 효율성이 있는 것으로 추정되었다. 따라서 고급육형 한우개량을 위한 초음파 측정치를 이용한 검정방법을 활용하고 이를 이용한 종축선발을 실시할 때 개량효율을 크게 향상시킬 수 있을 것으로 사료되었다. 반면에 각 형질별 개량 효율성을 살펴보면 개량효율성이 가장 낮은 형질은 근내지방도로써 이는 표현형 변이가 상대적으로 낮은 형질에 선발의 가중치를 동일하게 가정한 것에 기인된 것으로 사료되며 따라서 근내지방도의 변이를 크게 할 수 있는 자료조사방법의 변경, 또는 선발의 가중치를 높이는 방법에 대한 연구가 필요할 것으로 사료되었다. Simulation studies were carried out to investigate the responses of selection for three carcass traits (longissimus muscle area: EMA, fat thickness: BF, and marbling score: MS) based on either adjusted phenotypes (APH) or estimated breeding values (EBV) in multivariate animal model with different breeding schemes. Selection responses were estimated and compared on six different models with respect to breeding schemes using either carcass measurements or real time ultrasonic (RTU) scans generated by Monte Carlo computer simulation supporting closed breeding population. From the base population with 100 sires and 2000 dams, 20 sires and 1000 dams by each generation were selected by either APH or EBV for 10generations. Relative economic weights were equal of three traits as EMA(1): BF(-1) : MS(1) for standardized either APH or EBV. For first two models which were similarly designed with current progeny-test program in Korean cattle, three carcass traits with records either only on male progenies (Model 1) or on male and female progenies (Model 2) were used for selecting breeding stocks. Subsequently, generation intervals on males were assumed as 6~10 years in these two models. The other two models were designed with tools of selection by RTU rather than carcass measurements with genetic correlations of 0.81~0.97 between RTU and corresponding carcass traits in addition to whether with records (Model 4) or without records (Model 3) on female. In these cases, generation intervals on males were assumed as 2~4 years. The remaining last two models were designed as similar with Models 3 and 4 except genetic correlations of 0.63~0.68 between RTU and corresponding carcass traits with records (Model 6) and without records (Model 5) on females. The results from 10 replicates on each model and selecting methods suggested that responses indirect selection for carcass traits in Model 4 were 1.66~2.44 times efficient rather than those in Model 1. Otherwise, in Model 6 with assuming moderate genetic correlations, those efficiencies were 1.18~2.08 times with comparing to responses in Model 1. However, selection response for marbling score was the smallest among three carcass traits because of small variation of measurements. From these results, this study suggested that indirect selection using RTU technology for improving high meat qualities in Korean cattle would be valuable with modifying measuring rules of marbling score forward to large variation or modifying relative economic weight for selection.

한우의 이유시 체중 및 도체형질들에 대한 Bayesian 추론과 Al - REML 간에 유전모수 및 육종가 추정치 비교

이득환 한국동물자원과학회 2001 한국축산학회지 Vol.43 No.3

Heritabilities and Genetic correlations among weaning weight and carcass traits in Korean cattle (Hanwoo) were estimated in multivariate animal model using threshold model with Bayesian inference via Gibbs sampling (TM-GIBBS) and using average information algorithm with restricted maximum likelihood (AI-REML). Those estimates were compared with each other to find out genetic property of each trait according to analytic methodologies. Multivariate animal models were set up with maternal effects for weaning weight and additive genetic effects for all traits in this study and considered age of weaning and age of slaughtering as covariates. Data were 1762 records with missing traits and 3762 animals with pedigree from progeny test program by Agricultural Co-operative Federation and the National Livestock Research Institute in Rural Development Administration in Korea. It was enable to converge to relevant criteria point when average information method for likelihood function of parameters by second derivative and Fisher scoring iteration method was used. Furthermore, all parameter estimates using multivariate threshold model and Gibbs sampling also showed to a consistent property even though estimates were different with each other. Heritability estimates for weaning weight and carcass traits by TM-GIBBS were higher than those by AI-REML in Henderson's MME. In special, heritability estimates of MS were 0.43∼0.65 within 95 confidential interval by TM-GIBBS and 0.351 by AI-REML. Genetic correlations between maternal genetic effects of WWT and direct genetic effects of MS were negatively estimated as -0.33 by TM-GIBBS and AI-REML methods. The correlations of breeding values for marbling score between by TM-GIBBS and by AI-REML were slightly lower as 0.966 in Pearson's correlation and 0.970 in Spearman's rank correlation than those for other traits in this study. This study showed that threshold model of categorical trait and other linear type traits were valid and adaptable to genetic evaluation in Korean cattle.

한우의 주요 경제형질에 대한 유전모수 추정 2 . Henderson 방법에 3 에 의한 증체형질들에 대한 유전력 및 유전상관 (遺傳相關)

이득환,오봉국,박영일,신언익,양영훈 ( D . H . Lee,B . K . Ohh,Y . I . Park,O . Y . Shin,Y . H . Yang ) 한국축산학회 1991 한국축산학회지 Vol.33 No.7

Heritabilities and genetic correlations were estimated by Henderson`s method 3 on the basis of the data from 867 heads of Korean native cattle tested at Korea Native Cattle Improvement Center. The traits for estimation of genetic parameters were body weights at birth, weaning, yearling. and 18-month of age, and chest girth at yearling age. The heritability estimates were 0.12±0.08 at birth weight, 0.31±0.17 at weaning weight. 0.11±0.08 at gain after weaning, and 0.19±0.07 at yearling weight. The genetic correlation between birth weight and gain after weaning was negatively estimated(-0.60), but that between gain after weaning and yearling weight was positively estimated(0.66).

빅데이터를 사용한 시스템 트레이딩 : KOSPI200 선물을 대상으로

이득환,김수현,강형구 한국재무학회 2014 한국재무학회 학술대회 Vol.2014 No.05

오늘날 우리는 빅데이터를 통해 보다 광범위하고 대규모적이며 정확한 자료를 단시간에 추출 가 능하게 되었다. 이러한 관점에서 본 연구는 빅데이터에 나타난 투자자별 감성이나 정보가 KOSPI200 선물 지수 수익률에 미치는 영향력을 실증 분석하였다. 특히 빅데이터 관련 변수를 새 롭게 정의하고 VAR, 로지스틱 회귀 분석을 통한 예측력을 검정하였다. 이후 예스트레이더를 사용 한 시스템 트레이딩 전략을 적용함으로써 빅데이터를 사용한 투자 전략이 높은 수익을 가져옴을 증명하였다. 실증 분석 결과 빅데이터는 KOSPI200 선물 지수 수익률을 예측하는 정보를 포함한 다는 것을 알 수 있었다. 이러한 실증 분석 결과를 통해 볼 때 본 연구는 개인 투자자의 감성 분 석에서 한 단계 나아가 빅데이터를 활용하여 전문적인 투자자들의 감성, 정보에 대한 추가적인 검증이 필요하다는 것을 시사한다.

번식 육종 1 ; 한우의 종모우 평가방법에 관한 연구 2. 선발지수식과 BLUP 에 의한 단형질 및 다형질 평가방법의 비교

이득환,이문걸,신언익 한국동물자원과학회 ( 구 한국축산학회 ) 1992 한국축산학회 심포지움자료집 Vol.- No.-

범주형 자료를 포함한 다형질 임계개체 모형에서 유전능력 추정 알고리즘

이득환 한국동물자원과학회 2004 한국축산학회지 Vol.46 No.2

Algorithms for estimating breeding values on several categorical data by using latent variables with threshold conception were developed and showed. Thresholds on each categorical trait were estimated by Newton's method via gradients and Hessian matrix. This algorithm was developed by way of expansion of bivariate analysis provided by Quaas(2001). Breeding values on latent variables of categorical traits and observation on linear traits were estimated by preconditioned conjugate gradient(PCG) method, which was known having a property of fast convergence. Example was shown by simulated data with two linear traits and a categorical trait with four categories(CE=calving ease) and a dichotomous trait(SB=Still Birth) in threshold animal mixed model(TAMM). Breeding value estimates in TAMM were compared to those in linear animal mixed model (LAMM). As results, correlation estimates of breeding values to parameters were 0.91~0.92 on CE and 0.87~0.89 on SB in TAMM and 0.72~0.84 on CE and 0.59~0.70 on SB in LAMM. As conclusion, PCG method for estimating breeding values on several categorical traits with linear traits were feasible in TAMM.

Holstein 젖소의 선형심사형질과 등급형질에 대한 유전변이 추정

이득환 한국동물자원과학회 2006 한국축산학회지 Vol.48 No.2

한우의 주요 경제형질에 대한 유전모수 추정 1 . 체중 및 흉위에 대한 일반능력 및 자료의 분포 특성

이득환,오봉국,박영일,신언익,양영훈 ( D . H . Lee,B . K . Ohh,Y . I . Park,O . Y . Shin,Y . H . Yang ) 한국축산학회 1991 한국축산학회지 Vol.33 No.7

This study was carried out to seek the effects of environmental factors and properties of growth as being based on genetic evaluation of Korean native cattle. Analytic data were collected from 973 heads of male calves tested at Korea Native Cattle Improvement Centre from 1985 to 1988. Body weight at birth, weaning. yearling, and gain from weaning to yearling were affected highly(99.99%) by testing year-season and location at birth but the effects of parity was a little significant for growth traits. As data of chest girth at yearling showed highly skewed distribitions. it might be requested for transformation of data for genetic evaluation.