• Title/Summary/Keyword: Indirect Selection

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Selection Responses for Milk, Fat and Protein Yields in Zimbabwean Holstein Cattle

  • Mandizha, S.;Makuza, S.M.;Mhlanga, F.N.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.7
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    • pp.883-887
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    • 2000
  • One way of evaluating the effectiveness of a dairy breeding program is to measure response to selection. This may be direct or indirect. The objectives of this study were to estimate expected progress for direct selection on milk, fat and protein yields; to estimate the expected correlated responses on indirect selection for milk, fat and protein yields in Zimbabwean Holstein cattle and to establish the effect of selection intensity on responses. The Animal Model contained fixed effects of herd, year of calving, calving month, dry period, milking frequency and additive effects pertaining to cows, sires and dams. AIREML software package was used to analyse the data. The genetic and phenotypic parameters obtained in this study were used to compute direct and correlated responses to selection. Because of the higher heritabilities in first parity, genetic progress was found to be greater when selection was practised on first parity cows as compared to later lactations. It is therefore recommended that older cows in the herd be replaced with improved heifers so as to enhance genetic progress.

Indigenous Thai Beef Cattle Breeding Scheme Incorporating Indirect Measures of Adaptation: Sensitivity to Changes in Heritabilities of and Genetic Correlations between Adaptation Traits

  • Kahi, A.K.;Graser, H.U.
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.8
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    • pp.1039-1046
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    • 2004
  • A model Indigenous Thai beef cattle breeding structure consisting of nucleus, multiplier and commercial units was used to evaluate the effect of changes in heritabilities of and genetic correlations between adaptation traits on genetic gain and profitability. A breeding objective that incorporated adaptation was considered. Two scenarios for improving both the production and the adaptation of animals where also compared in terms of their genetic and economic efficiency. A base scenario was modelled where selection is for production traits and adaptation is assumed to be under the forces of natural selection. The second scenario (+Adaptation) included all the information available for base scenario with the addition of indirect measures of adaptation. These measures included tick count (TICK), faecal egg count (FEC) and rectal temperature (RECT). Therefore, the main difference between these scenarios was seen in the records available for use as selection criteria and hence the level of investments. Additional genetic gain and profitability was generated through incorporating indirect measures of adaptation as criteria measured in the breeding program. Unsurprisingly, the results were sensitive to the changes in heritabilities and genetic correlations between adaptation traits. However, there were more changes in the genetic gain and profitability of the breeding program when the genetic correlations of adaptation and its indirect measures were varied than when the correlations between these measures were. The changes in the magnitudes of the genetic gain and profit per cow stresses the importance of using reliable estimates of these traits in any breeding program.

Techniques and Characteristics of Indirect Restorations

  • Cho, Kyung-Mo
    • Proceedings of the KACD Conference
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    • 2001.11a
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    • pp.593-593
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    • 2001
  • Esthetic restoration techniques can be categorized into "Direct techniques" consist only of intraoral procedures and "Indirect techniques" include intraoral as well as extraoral laboratory steps. Those made extraorally exhibit generally enhanced esthetic potential and anatomy and better hardness and wear resistance, indirect esthetic restorations numerously applied in contemporary dentistry. Indirect restorative materials can be divided into two categories; composite resin-based materials and ceramic-based materials. These materials shows various were resistance, modulus of elasticity, repair postenital, chemical stability, and different laboratory procedures. In this session, benefit of indirect techinques, case selection of this kind of restorations, and material characteristics and fabrication produre of those materials will ber reviewed; Targis, Sculpture, Belleglass, and Post-curing of restorative composite resins in resin-based materials; Dicor, Empress, Cerec, Celay, and conventional firing porcelain in ceramic based materials.

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Estimation of Genetic Correlations and Selection Responses for Carcass Traits between Ultrasound and Real Carcass Measurements in Hanwoo Cows

  • Son, Jihyun;Lee, Deukhwan
    • Journal of Animal Science and Technology
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    • v.55 no.6
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    • pp.501-508
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    • 2013
  • This study was conducted to determine genetic correlations among carcass traits measured by ultrasound and real carcass measurements and to estimate indirect selection responses for real carcass traits based on ultrasound measurements in Hanwoo cows. To accomplish this, 22,080 ultrasound measurement records from 17,926 cows collected from 2001 to 2012 and 11,907 carcass records obtained from fattened cattle from 2008 to 2012 were used. Genetic parameters were estimated based on eye muscle area (EMA), backfat thickness (BF) and marbling score (MS) measured by ultrasound-scanning of live cows and using the official technique on chilled bovine half-carcasses after slaughtering. Heritability and genetic correlation for carcass traits were estimated using a mixed model equation that consisted of environmental effects as fixed parameters and additive genetic effects and residual effects as random parameters, assuming that traits were different between ultrasound and carcass measurements. This statistical method was applied to the average information restricted maximum likelihood method. The heritability of EMA, BF and MS measured by ultrasound were 0.33, 0.61 and 0.46, respectively, while the heritability estimates of the corresponding traits based on carcass measurements were 0.29, 0.40 and 0.38, respectively and the genetic correlation between ultrasound and carcass traits for EMA, BF and MS were 0.41, 0.78 and 0.67, respectively. The genetic correlation between ultrasound and carcass traits was highly positive. Additionally, the selection response for marbling score was estimated to be 0.42 per generation if the cows were selected based on the ultrasound scan marbling score with an assumed selection intensity of 0.8. Overall, these results indicate that the ultrasound scan technique would be applicable to judging cow selection for genetically improved meat quality.

Comparisons of Index Numbers: An Application to Sawmills and Planing Mills Industry of U.S.

  • Ahn, SoEun
    • Journal of Korean Society of Forest Science
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    • v.94 no.2 s.159
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    • pp.82-89
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    • 2005
  • The purpose of this paper is to investigate index numbers by conducting various comparisons among the widely used index formulas. The comparison is considered in three ways; 1) divergences in the magnitudes of index numbers due to the use of different formulas (Laspeyres, Paasche, Fisher, and Tornqvist); 2) the effect of selection of base year (fixed-year base vs. chain-type); 3) the degree of approximation of indirect to direct quantity index. The empirical application is to sawmills and planing mills industry of U.S. using a national time series data covering years of 1948-2000. The results show that the differences between Laspeyres and Paasche index can be substantial in some cases while the difference between Fisher and Tornqvist index is minimal. We also confirm that the selection of base year can cause significant divergences, especially when the variables undergo rapid price or quantity changes over time. We find that indirect quantity index approximates direct quantity index reasonably well in U.S. sawmill industry.

Statistical Genetic Studies on the Selection for Grain Characteristics of Malting Barley (Hordeum distichum L.) (맥주맥(Hordeum distichum, L.)의 우량품종 육성에 있어서 입형질의 선발에 관한 통계유전학적 연구)

  • Bong-Ho Lee;In-Gul Lee
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.21 no.1
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    • pp.71-81
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    • 1976
  • This study was carried out to attain the selection information on grain characters of malting barley. Indirect selection, making use of information on grain thickness, seemed to be an effective method for the selection of 1, 000 grain weight, grain hull and grain yield which were directly affected by grain thickness. Grain yield which had a direct effect on grain, meal and protein content seemed to be an effective selection indicator for them, however, a better method is expected upon improvement of indirect effects of hull and grain yield.

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Considering the Multi-Purpose Display Designed for Aircraft Lightning Protection (낙뢰보호를 고려한 항공기용 다목적 디스플레이 설계)

  • Cheon, Young-Ho;Lee, Seoung-Pil;Park, Jun-Hyeon
    • Journal of Advanced Navigation Technology
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    • v.18 no.5
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    • pp.445-454
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    • 2014
  • In this paper, we introduce measures designed content for RTCA DO-160 F, Section 22 tests performed to verify the effects of indirect lightning and testing process of the test was carried out in the multi-purpose display certification process. This is referred to as indirect effects of lightning capability of an aircraft having electrical electronic equipment failure or damage to bring lightning induced voltages. In order to protect the avionics from lightning indirect effects of these aircraft are analyzing the effects of lightning strikes on aircraft and aircraft systems and interior design needs protection against the threat on their part. In this paper, we introduce RTCA DO-160 F, component selection process according to Section 22 category selection method and the selected level for determining the level of such measures for protection against lightning of multipurpose display for this aircraft. It also introduces the actual test process to confirm that the designed effectiveness of the selected part. We expect a good example of the lightning planned for future development of measures designed avionics through each step of the process introduced this.

The Analysis of Helicopter Maneuvering Flight Using the Indirect Method - Part II. Applicability of High Fidelity Helicopter Models (Indirect Method를 이용한 헬리콥터 기동비행 해석 - Part II. High Fidelity 헬리콥터 모델링의 사용 가능성)

  • Kim, Chang-Joo;Yang, Chang-Deok;Kim, Seung-Ho;Hwang, Chang-Jeon
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.36 no.1
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    • pp.31-38
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    • 2008
  • This paper deals with the nonlinear optimal control approach to helicopter maneuver problems using the indirect method. We apply a penalty function to the integral deviation from a prescribed trajectory to convert the system optimality to an unconstrained optimal control problem. The resultant two-point boundary value problem has been solved by using a multiple-shooting method. This paper focuses on the model selection strategies to resolve the problem of numerical instability and high wait time when a high fidelity model with rotor dynamics is applied. Four different types of helicopter models are identified, two of which are linear models with or without rotor models, as well as two models which include the nonlinear mathematical model for rotor in its formulation. The relative computation time and the number of function calls for each model are compared in order to provide a guideline for the selection of helicopter model.

A Study on the Cosmetics Store Selection Behavior - Department Stores and Large-Scale Discount Stores - (화장품(化粧品) 점포선택행동(店鋪選擇行動)에 관(關)한 연구(硏究) - 백화점(百貨店)과 대형할인점(大形割引店)을 중심(中心)으로 -)

  • Sun, Jung-Hee;Yoo, Tai-Soon
    • Journal of Fashion Business
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    • v.8 no.2
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    • pp.42-55
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    • 2004
  • The purpose of this study was to classify the contents of department stores and large-scale discount stores of consumer on information source, shopping orientation and store image in an effort to determine which variable gave a crucial impact on cosmetics department stores and large-scale discount stores selection behavior. The subjects of this study were 557 adult women visited department store and large-scale discount store in Busan. The data were analyzed by using Factor analysis, Frequency analysis, Correlation analysis, Cronabach $\alpha$ and Regression analysis. The results were as follows; 1. There was a difference in the demographical characteristics on department stores and large-scale discount stores of consumers. 2. Shopping Orientation of consumers were categorized into 5 types, and information source of consumers did 3 types, and store image of consumers did 5 types. 3. Leisure utilization, store & brand loyalty, store information, personal information, massmedia information, product & operate on, store atmosphere & salesperson and shopping convenience had positive correlations with cosmetics department stores selection beavior. but convenient location, rationality & economy and sales promotion had negative correlations with cosmetics department stores selection beavior. 4. Rationality & economy and sales promotion had positive correlations with cosmetics large-scale discount stores selection beavior. but convenient location, leisure utilization, store & brand loyalty, massmedia information, product & operate on, store atmosphere & salesperson and shopping convenience had negative correlations with cosmetics large-scale discount stores selection beavior. 5. Age, income, business(-), convenient location(-), rationality & economy(-), leisure utilization, store & brand loyalty, store information, personal information, massmedia information, store atmosphere & salesperson, shopping convenience and sales promotion(-) had a direct effect on cosmetics department stores selection beavior. Age, income, marriage, education had an indirect effect on department stores selection beavior through information source and store image, and information source did through store image, and shopping orientation did through store image. 6. Rationality & economy, convenient location(-), leisure utilization(-), store & brand loyalty(-), buying independence(-), personal information, massmedia information(-), product & operate on(-), shopping convenience(-) and sales promotion had a direct effect on cosmetics large-scale discount stores selection beavior. Age, income, marriage, education had an indirect effect on large-scale discount stores selection beavior through information source, shopping orientation and store image, and information source did through store image, and shopping orientation did through store image.

Genetic Evaluation and Selection Response of Birth Weight and Weaning Weight in Indigenous Sabi Sheep

  • Assan, N.;Makuza, S.;Mhlanga, F.;Mabuku, O.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.12
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    • pp.1690-1694
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    • 2002
  • Genetic parameters were estimated for birth weight and weaning weight from three year (1991-1993) data totalling 1100 records of 25 rams to 205 ewes of Indigenous Sabi flock maintained at Grasslands Research Station in Zimbabwe. AIREML procedures were used fitting an Animal Model. The statistical model included the fixed effects of year of lambing, sex of lamb, birth type and the random effect of ewe. Weight of ewe when first joined with ram was included as a covariate. Direct heritability estimates of 0.27 and 0.38, and maternal heritability estimates of 0.24 and 0.09, were obtained for birth weight and weaning weight, respectively. The total heritability estimates were 0.69 and 0.77 for birth weight and weaning weight, respectively. Direct-aternal genetic correlations were high and positive. The corresponding genetic covariance estimates between direct and maternal effects were positive and low, 0.25 and 0.18 for birth weight and weaning weight, respectively. Responses to selection were 0.8 kg and 0.14 kg for birth weight and weaning weight, respectively. The estimated expected correlated response to selection for birth weight by directly selecting for weaning weight was 0.26. Direct heritabilities were moderate; as a result selection for any of these traits should be successful. Maternal heritabilities were low for weaning weight and should have less effect on selection response. Indirect selection can give lower response than direct selection.