• Title/Summary/Keyword: Curve Parameters

Search Result 1,813, Processing Time 0.026 seconds

Estimation of genetic relationships between growth curve parameters in Guilan sheep

  • Hossein-Zadeh, Navid Ghavi
    • Journal of Animal Science and Technology
    • /
    • v.57 no.5
    • /
    • pp.19.1-19.6
    • /
    • 2015
  • The objective of this study was to estimate variance components and genetic parameters for growth curve parameters in Guilan sheep. Studied traits were parameters of Brody growth model which included A (asymptotic mature weight), B (initial animal weight) and K (maturation rate). The data set and pedigree information used in this study were obtained from the Agricultural Organization of Guilan province (Rasht, Iran) and comprised 8647 growth curve records of lambs from birth to 240 days of age during 1994 to 2014. Marginal posterior distributions of parameters and variance components were estimated using TM program. The Gibbs sampler was run 300000 rounds and the first 60000 rounds were discarded as a burn-in period. Posterior mean estimates of direct heritabilities for A, B and K were 0.39, 0.23 and 0.039, respectively. Estimates of direct genetic correlation between growth curve parameters were 0.57, 0.03 and -0.01 between A-B, A-K and B-K, respectively. Estimates of direct genetic trends for A, B and K were positive and their corresponding values were $0.014{\pm}0.003$ (P < 0.001), $0.0012{\pm}0.0009$ (P > 0.05) and $0.000002{\pm}0.0001$ (P > 0.05), respectively. Residual correlations between growth curve parameters varied form -0.52 (between A-K) to 0.48 (between A-B). Also, phenotypic correlations between growth curve parameters varied form -0.49 (between A-K) to 0.47 (between A-B). The results of this study indicated that improvement of growth curve parameters of Guilan sheep seems feasible in selection programs. It is worthwhile to develop a selection strategy to obtain an appropriate shape of growth curve through changing genetically the parameters of growth model.

Procedure of drawing fragility curve as a function of material parameters

  • Kim, Jang-Ho;Li, Jing;Park, Jeong-Ho;Hong, Jong-Seok
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2006.05a
    • /
    • pp.334-337
    • /
    • 2006
  • Generally, fragility curve has been used in predicting failure of structures due to seismic actions. In this research, the method of drawing fragility curve has been applied to evaluating success/failure of structures and satisfactory/unsatisfactory of concrete mixture performance based on material parameters. In the paper, a detailed explanation of the procedure of drawing fragility curve based on material parameter has been introduced. Fragility curve generating procedure includes generation of virtual data points from limited number of actual data points by bell curve implementation, determination of success/failure status of each data point by assigned criterion, and completion of final fragility curve. For practical applications, workability of concrete mixture content based on "unit water" has been used to obtain fragility curve. Detailed explanation of fragility curve drawing procedure for material parameters is presented.

  • PDF

Geometric Fitting of Parametric Curves and Surfaces

  • Ahn, Sung-Joon
    • Journal of Information Processing Systems
    • /
    • v.4 no.4
    • /
    • pp.153-158
    • /
    • 2008
  • This paper deals with the geometric fitting algorithms for parametric curves and surfaces in 2-D/3-D space, which estimate the curve/surface parameters by minimizing the square sum of the shortest distances between the curve/surface and the given points. We identify three algorithmic approaches for solving the nonlinear problem of geometric fitting. As their general implementation we describe a new algorithm for geometric fitting of parametric curves and surfaces. The curve/surface parameters are estimated in terms of form, position, and rotation parameters. We test and evaluate the performances of the algorithms with fitting examples.

A Study for Precision Equation and Transition curve of Vertical Curve (종곡선의 정밀식과 완화곡선에 관한 연구)

  • Shin, Soon-Ho;Kim, Yong-Eul
    • Proceedings of the KSR Conference
    • /
    • 2008.06a
    • /
    • pp.1676-1682
    • /
    • 2008
  • The vertical curve of railway is installed in changing point where the gradient is more than a certain degree to ensure safe operation of train and comfort of passengers. As a result of CAD work with 3D coordination by using the existing equation, it was found that the simple equation about vertical curve installation suggested in the surveying engineering or railway regulations did not reflect theoretical curvature of circular curve in a case of steep grade and large vertical radius. In this study, for derive precision equation and transition curve about vertical curve, gradient parameters, equation of circles and transition curve equation were used, and it was verified by CAD that the derived equation is exactly satisfied with parameters of geometrical circular and transition curve. This equation could be used to provide more smoothing operation of train and comfort of passengers on vertical curves, especially in case that railway requires precision vertical alignment of track such as super high-speed railway, LRT or Maglev system.

  • PDF

Control of Manipulators with Hyper Degrees of Freedom:Shape Control Based on Curve Parameter Estimation

  • Mochiyama, Hiromi;Shimemura, Etsujiro;Kobayashi, Hisato
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1996.10a
    • /
    • pp.12-15
    • /
    • 1996
  • In this paper, a new shape control law is derived as a result of introducing the parametric curve representation. This control alw is based on the estimation of the curve parameters corresponding to the target joint positions and the target tip position. Estimating target curve parameters makes it possible to find, easily, a simple shape control law by the Lyapunov design method.

  • PDF

HOMOGENEOUS SOLUTION FOR SW LACERTAE

  • Kim, Kyung-Joo;Kang, Young-Woon
    • Journal of Astronomy and Space Sciences
    • /
    • v.13 no.1
    • /
    • pp.19-31
    • /
    • 1996
  • We have analyzed collected photoelectric light curves for light variations of SW Lac. The method of Fourier analysis was adopted to quantify the light variation from season to season. We found the linear relation between the Fourier coefficient, B1 and the magnitude difference between two maxima. The total light of the system has been decreased as much as 0m.04 during approxiamately 20 years time interval. Photoelectric parameters including spot parameters for all light curves were obtained by the method of the Wilson and Devinney differential correction in order to secure the variations of parameters from season to season. SW Lac, not like RS CVn type stars, required to adjust all parameters as well as spot parameters for a reasonable fit to the observations of each epoch. A surface temperature of cooler star is one of the most sensitive parameters to affect a shape of light curve of SW Lac. We conclude that the shape of light curve of SW Lac varies even during one season as well as season to season. The light curve is mainly caused by inhomogeneous surface temperature due to strong chromospheric activity of the system.

  • PDF

Effects of season and age at first calving on genetic and phenotypic characteristics of lactation curve parameters in Holstein cows

  • Torshizi, Mahdi Elahi
    • Journal of Animal Science and Technology
    • /
    • v.58 no.2
    • /
    • pp.8.1-8.14
    • /
    • 2016
  • In this research data representing 72,946 primiparous cows from 724 herds with 638,063 total test day records calved between 2001 and 2011. These data were analysed to determine the effect of age at first and season of calving on parameters of the Wood lactation curve. Also, genetic trend of the lactation curve parameters in different calving years were evaluated. The results indicate that the highest rate of atypical lactation curve was related to cows that calved in summer (28.05 %). The maximum phenotypic relationship between initial milk yield and total 305-d milk yield was observed in cows calved in spring (0.40). The role of peak yield is more than peak time on 305-d total milk yield in primiparous Holstein. One month increase in age at first calving from 18 to 26 month raised 305-d milk yield by around 138 kg and from 27 to 32 month decreased by 61 kg. The persistency of lactation between 101 and 200 days is higher than that of 201-305 days. Our results indicate that the shape of lactation curve is largely dependent on the season of calving (higher level of milk production in cows which calved in autumn and winter). The heritabilities of parameters of lactation curve and persistency measures were low. The genetic trends for peak time, peak yield and 305-d milk yields were positive and estimated to be 0.019, 0.021 and 8.13 kg/year respectively. So the range from 24 to 26.5 month of calving is the optimum calving time in primiparous Holstein for maximizing 305-d milk yield.

The effect of extended lactation on parameters of Wood's model of lactation curve in dairy Simmental cows

  • Kopec, Tomas;Chladek, Gustav;Falta, Daniel;Kucera, Josef;Vecera, Milan;Hanus, Oto
    • Animal Bioscience
    • /
    • v.34 no.6
    • /
    • pp.949-956
    • /
    • 2021
  • Objective: This study was focused on the estimation of parameters of Wood's model and description of the lactation curve using the cows which were lactated over 24 months on the first lactation. Methods: The database included 1,333 pure-bred dairy Simmental primiparous cows which lactated for 24 months (732 days). The initial dataset entering the procedure of assessment of parameters of Wood's function included 35,826 milk yield records. Milk yield was recorded throughout lactation, with the earliest record taken on day 6 and the latest on day 1,348 of lactation. This dataset was used for the assessment of parameters a, b, c of Wood's model using the non-linear statistical procedure. These parameters were estimated for different length of lactation. The assessed parameters were used for calculation of some characteristics of lactation curves. Results: The lowest value of a parameter (15.2317) of Wood's model of lactation curve was found out in lactations up to 305 days long, contrary to b and c parameters which were highest in those lactations (0.1029 and 0.0015, respectively). The maximum value of a parameter (17.4329) was found out in lactations up to 640 days long, unlike b and c parameters which were minimal in those lactations (0.0603 and 0.0010, respectively). Conclusion: It can be concluded that the parameters of Wood's model and the shape of lactation curve are changing with the growing number of milk yield records. Also, the assessed parameters revealed a significant milk production potential after 305 days of lactation.

The Retrieval of Abnormal TL Glow Curves Using Modified Glow Curve Analysis Method

  • Lee, Sang-Yoon;Lee, Kun-Jai;Kim, Jang-Lyul;Chang, Si-Young
    • Nuclear Engineering and Technology
    • /
    • v.29 no.5
    • /
    • pp.385-392
    • /
    • 1997
  • The shape of TL glow curve is a useful indicator for assurance of correct reading of the personal dosimeter. Since the reading procedure of TLD is irreversible, however, an analytic remedy should be considered to procure reliable dosimetric information for the readings with irregular glow con shape. In this study, kinetic trapping parameters of CaSO$_4$ : Dy Teflon personal dosimeter(Teledyne PB-6A) were analyzed by Halperin and Braner's model for general-order kinetics. From these kinetic tapping parameters, we also developed a simple procedure to retrieve the dosimetric information from abnormally distorted glow curves. The computerized glow curve deconvolution(CGCD) fitting of the reference glow curve with kinetic parameters from this study yields relative errors of about 5% from the expected integral. It was also found that the glow curve remedial procedure developed could retrieve the distorted TL glow curves within ewer ranges of 1575. With the glow curve retrieval techniques, doses incurred by gamma radiation can now be successfully re-constructed for the CaSO$_4$ : Dy Teflon dosimeter resulting abnormal glow curves.

  • PDF

Multi-thresholds Selection Based on Plane Curves (평면 곡선에 기반한 다중 임계값 결정)

  • Duan, Na;Seo, Suk-T.;Park, Hye-G.;Kwon, Soon-H.
    • Journal of the Korean Institute of Intelligent Systems
    • /
    • v.20 no.2
    • /
    • pp.279-284
    • /
    • 2010
  • The plane curve approach which was proposed by Boukharouba et. al. is a multi-threshold selection method through searching peak-valley based on histogram cumulative distribution function. However the method is required to select parameters to compose plane curve, and the shape of plane curve is affected according to parameters. Therefore detection of peak-valley is effected by parameters. In this paper, we propose an entropy maximizing-based method to select optimal plane curve parameters, and propose a multi-thresholding method based on the selected parameters. The effectiveness of the proposed method is demonstrated by multi-thresholding experiments on various images and comparison with other conventional thresholding methods based on histogram.