• Title/Summary/Keyword: Genetic gains

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PID Tuning Based on RCGA Using Ziegler-Nichols Method (Ziegler-Nichols를 이용한 실수코딩 유전 알고리즘 기반의 PID 튜닝)

  • Park, Ji-Mo;Kim, Go-Eun;Kim, Jin-Sung;Park, Sung-Man;Heo, Hoon
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.19 no.5
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    • pp.475-481
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    • 2009
  • Real-coded genetic algorithm(RCGA) has better performances than conventional genetic algorithm about dealing with a large domain, the precision and the constrain problem. Also the RCGA has advantage of operation time because it doesn't have to following about decoding operation. In this paper the ranges of PID gains are limited based on Ziegler-Nichols method to consider a long operation time problem that is the main problem of genetic algorithm. Result shows proposed method represents better performance without ignored about result of ZN tuning method and reduces the calculation time.

An Experimental Study on an Optimal Controller for the Overhead Crane Using the Genetic Algorithm (유전자 알고리즘을 이용한 천정크레인의 최적제어기에 실험적 연구)

  • Choi, Hyeung-Sik;Kim, Kil-Tae
    • Journal of the Korean Society for Precision Engineering
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    • v.16 no.1 s.94
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    • pp.34-41
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    • 1999
  • This paper presents a HGA-based(hybrid genetic algorithm) optimal control strategy to control of the swing motion and the transfer of the overhead crane. The objective is to achieve the regulation of the fast swing motion or fast position control. The controller is based on the state feedback. The HGA-based optimal algorithm is applied to find optimal gains of the controller. Computer simulation and experiments were performed to demonstrate the effectiveness of the proposed control scheme.

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GA-LADRC based control for course keeping applied to a mariner class vessel (GA-LADRC를 이용한 Mariner class vessel의 선수각 제어)

  • Jong-Kap AHN
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.59 no.2
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    • pp.145-154
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    • 2023
  • In this study, to control the heading angle of a ship, which is constantly subjected to various internal and external disturbances during the voyage, an LADRC (linear active disturbance rejection control) design that focuses more on improving the disturbance removal performance was proposed. The speed rate of change of the ship's heading angle due to the turn of the rudder angle was selected as a significant factor, and the nonlinear model of the ship's maneuvering equation, including the steering gear, was treated as a total disturbance. It is the similar process with an LADRC design for the first-order transfer function model. At this time, the gains of the controller included in LADRC and the gains of the extended state observer were tuned to RCGAs (real-coded genetic algorithms) to minimize the integral time-weighted absolute error as an evaluation function. The simulation was performed by applying the proposed GA-LADRC controller to the heading angle control of the Mariner class vessel. In particular, it was confirmed that the proposed controller satisfactorily maintains and follows the set course even when the disturbances such as nonlinearity, modelling error, uncertainty and noise of the measurement sensor are considered.

System Parameter Estimation and PID Controller Tuning Based on PPGAs (PPGA 기반의 시스템 파라미터 추정과 PID 제어기 동조)

  • Shin Myung-Ho;Kim Min-Jeong;Lee Yun-Hyung;So Myung-Ok;Jin Gang-Gyoo
    • Journal of Institute of Control, Robotics and Systems
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    • v.12 no.7
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    • pp.644-649
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    • 2006
  • In this paper, a methodology for estimating the model parameters of a discrete-time system and tuning a digital PID controller based on the estimated model and a genetic algorithm is presented. To deal with optimization problems regarding parameter estimation and controller tuning, pseudo-parallel genetic algorithms(PPGAs) are used. The parameters of a discrete-time system are estimated using both the model adjustment technique and a PPGA. The digital PID controller is described by the pulse transfer function and then its three gains are tuned based on both the model reference technique and another PPGA. A set of experimental works on two processes are carried out to illustrate the performance of the proposed method.

COMPARATIVE GENOMIC HYBRIDIZATION STUDIES ON CHOLANGIOCARCINOMA IN KOREA

  • Lee, Chul-Hoon;Park, Bu-Young;Kim, Min--Kyoung;Jee- Hong Kyhm;Park, Ho-Soon;Cho, Youl-Hee
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2001.10a
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    • pp.190-190
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    • 2001
  • The elucidation of the genetic changes of cholangiocarcinoma is very important for understanding the molecular mechanism of carcinogenesis and progression of cholangiocarcinoma. In order to identify the gains or losses of the copy number of DNA sequence in cholangiocarcinoma, we used comparative genomic hybridization to study 33 cases of cholangiocarcinoma. The whole DNAs from each tumor tissue were labeled with different fluorochromes and then simultaneously hybridized to normal metaphase spread chromosomes.(omitted)

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Relative Genetic Effects of Duroc and Taoyuan Breeds on the Economic Traits of Their Hybrids

  • Yen, N.T.;Tai, C.;Cheng, Y.S.;Huang, M.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.4
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    • pp.447-454
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    • 2001
  • For determining the relative genetic effects of Duroc (D) and Taoyuan (T) breeds on the economic traits of their hybrids, 72 litters of pigs, from four mating types, namely TT (T♂$\times$T♀), DD (D♂$\times$D♀) and D-T hybrids (TD, T♂$\times$D♀ and DT, D♂$\times$T♀) were used in this study. The various crossbreeding parameters were estimated by comparisons among mating types using linear contrasts of least-square analysis. The results of reproductive traits analysis showed that T breed had contributed superior genetic effects on the total number of piglets at birth (TBN) (p<0.10) and number of live piglets at 21 days (LP21) (p<0.05) to the D-T hybrids. Estimates of maternal genetic effects showed that the T females were superior in TBN (p<0.05), but inferior in average birth weight (ABW) and average litter birth weight (LBW) (p<0.01) to the D females. Direct heterosis effects were significant for LBW, LP21 and LWT21 (p<0.01). Least-squares analysis of other economic traits showed that T breed had relative negative effects on all growth traits, withers height (WH), body type index (BTI), average backfat thickness (ABF), carcass length (LENG), loin eye area (longissimus) (LEARA), and lean percentage (LEAN) of D-T hybrids (p<0.05). Estimates of direct genetic effects showed that the D breed was superior to the T breed in all growth and carcass traits except the average backfat (BF). Estimates of maternal genetic effects showed that average body weight at 180 days (WT180) of progenies from T sows were lighter than from D sows. Progenies from D females had larger and leaner carcass than those from T females. Direct heterosis effects were significant for average daily weight gains from 150 to 180 days ($ADG_{150-180}$) (p<0.05) and for average body weights at 150 (WT150), and 180 days (WT180), average daily weight gains from birth to 150 and 180 days ($ADG_{150}$ and $ADG_{180}$, respectively), WH, body length (BL), ABF, BTI, and LENG (p<0.01). The results showed that D-T hybrids tended to have superior TBN and LP21 than D breed, and to be superior in all growth and most conformation and carcass traits to the T breed.

A Design of Tracking Controller of Wheeled Mobile Robot using Fuzzy Logic and Genetic Algorithm (퍼지논리와 유전알고리즘을 이용한 차륜형 이동로봇의 제어기 설계)

  • Kim, Dae-Jun;Choi, Young-Kiu
    • Proceedings of the KIEE Conference
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    • 2000.07d
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    • pp.2837-2839
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    • 2000
  • We design a stable controller for a mobile robot with variable gains and reference velocity in order to apply the proper gains and reference velocity, which are generated with fuzzy logic in on-line. The stability is guranteed by the Lyapunov theory. The fuzzy logic rules is found in off-line with GA strategy which drives each object function to be the least. The proposed controller is applied smooth path tracking due to the local path planing. Simulation results show robust performances under a different initial conditions.

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Variance component analysis of growth and production traits in Vanaraja male line chickens using animal model

  • Ullengala, Rajkumar;Prince, L. Leslie Leo;Paswan, Chandan;Haunshi, Santosh;Chatterjee, Rudranath
    • Animal Bioscience
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    • v.34 no.4
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    • pp.471-481
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    • 2021
  • Objective: A comprehensive study was conducted to study the effects of partition of variance on accuracy of genetic parameters and genetic trends of economic traits in Vanaraja male line/project directorate-1 (PD-1) chicken. Methods: Variance component analysis utilizing restricted maximum likelihood animal model was carried out with five generations data to delineate the population status, direct additive, maternal genetic, permanent environmental effects, besides genetic trends and performance of economic traits in PD-1 chickens. Genetic trend was estimated by regression of the estimated average breeding values (BV) on generations. Results: The body weight (BW) and shank length (SL) varied significantly (p≤0.01) among the generations, hatches and sexes. The least squares mean of SL at six weeks, the primary trait was 77.44±0.05 mm. All the production traits, viz., BWs, age at sexual maturity, egg production (EP) and egg weight were significantly influenced by generation. Model four with additive, maternal permanent environmental and residual effects was the best model for juvenile growth traits, except for zero-day BW. The heritability estimates for BW and SL at six weeks (SL6) were 0.20±0.03 and 0.17±0.03, respectively. The BV of SL6 in the population increased linearly from 0.03 to 3.62 mm due to selection. Genetic trend was significant (p≤0.05) for SL6, BW6, and production traits. The average genetic gain of EP40 for each generation was significant (p≤0.05) with an average increase of 0.38 eggs per generation. The average inbreeding coefficient was 0.02 in PD-1 line. Conclusion: The population was in ideal condition with negligible inbreeding and the selection was quite effective with significant genetic gains in each generation for primary trait of selection. The animal model minimized the over-estimation of genetic parameters and improved the accuracy of the BV, thus enabling the breeder to select the suitable breeding strategy for genetic improvement.

Implementation of the Controller for a Stable Walking of a Humanoid Robot Using Improved Genetic Algorithm (개선된 유전 알고리즘 기반의 휴머노이드 로봇의 안정 보행을 위한 제어기 구현)

  • Kong, Jung-Shik;Lee, Eung-Hyuk;Kim, Jin-Geol
    • Journal of Institute of Control, Robotics and Systems
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    • v.13 no.5
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    • pp.399-405
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    • 2007
  • This paper deals with the controller for a stable walking of a humanoid robot using genetic algorithm. A humanoid robot has instability during walking because it isn't fixed on the ground, and its nonlinearities of the joints increase its instability. If controller isn't robust, the robot may fall down at the ground during walking because of its nonlinearities. To solve this problem, robust controller is required to reduce the effect of nonlinearities and to gain the good tracking performance. In this paper, motion controller that is based on fuzzy-sliding mode controller is proposed. This controller can remove the effect of the saturation by limitation of the input voltage. It also includes compensator for reducing the effect of the nonlinearity by backlash and PI controller improving the tracking performance. In here, genetic algorithm is used for searching the optimal gains of the controller. From the given controller, a humanoid robot can moved more preciously. All the processes are investigated through simulations and are verified experimentally in a real joint system for a humanoid robot.

Estimation of co-variance components, genetic parameters, and genetic trends of reproductive traits in community-based breeding program of Bonga sheep in Ethiopia

  • Areb, Ebadu;Getachew, Tesfaye;Kirmani, MA;G.silase, Tegbaru;Haile, Aynalem
    • Animal Bioscience
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    • v.34 no.9
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    • pp.1451-1459
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    • 2021
  • Objective: The objectives of the study were to evaluate reproductive performance and selection response through genetic trend of community-based breeding programs (CBBPs) of Bonga sheep. Methods: Reproduction traits data were collected between 2012 and 2018 from Bonga sheep CBBPs. Phenotypic performance was analyzed using the general linear model procedures of Statistical Analysis System. Genetic parameters were estimated by univariate animal model for age at first lambing (AFL) and repeatability models for lambing interval (LI), litter size (LS), and annual reproductive rate (ARR) traits using restricted maximum likelihood method of WOMBAT. For correlations bivariate animal model was used. Best model was chosen based on likelihood ratio test. The genetic trends were estimated by the weighted regression of the average breeding value of the animals on the year of birth/lambing. Results: The overall least squares mean±standard error of AFL, LI, LS, and ARR were 375±12.5, 284±9.9, 1.45±0.010, and 2.31±0.050, respectively. Direct heritability estimates for AFL, LI, LS, and ARR were 0.07±0.190, 0.06±0.120, 0.18±0.070, and 0.25±0.203, respectively. The low heritability for both AFL and LI showed that these traits respond little to selection programs but rather highly depend on animal management options. The annual genetic gains were -0.0281 days, -0.016 days, -0.0002 lambs and 0.0003 lambs for AFL, LI, LS, and ARR, respectively. Conclusion: Implications of the result to future improvement programs were improving management of animals, conservation of prolific flocks and out scaling the CBBP to get better results.