• 제목/요약/키워드: Adaptive adjustment

검색결과 136건 처리시간 0.021초

Many-objective Evolutionary Algorithm with Knee point-based Reference Vector Adaptive Adjustment Strategy

  • Zhu, Zhuanghua
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제16권9호
    • /
    • pp.2976-2990
    • /
    • 2022
  • The adaptive adjustment of reference or weight vectors in decomposition-based methods has been a hot research topic in the evolutionary community over the past few years. Although various methods have been proposed regarding this issue, most of them aim to diversify solutions in the objective space to cover the true Pareto fronts as much as possible. Different from them, this paper proposes a knee point-based reference vector adaptive adjustment strategy to concurrently balance the convergence and diversity. To be specific, the knee point-based reference vector adaptive adjustment strategy firstly utilizes knee points to construct the adaptive reference vectors. After that, a new fitness function is defined mathematically. Then, this paper further designs a many-objective evolutionary algorithm with knee point-based reference vector adaptive adjustment strategy, where the mating operation and environmental selection are designed accordingly. The proposed method is extensively tested on the WFG test suite with 8, 10 and 12 objectives and MPDMP with state-of-the-art optimizers. Extensive experimental results demonstrate the superiority of the proposed method over state-of-the-art optimizers and the practicability of the proposed method in tackling practical many-objective optimization problems.

적응적 EWMA 피드백 공정 조정 (Adaptive EWMA Feedback Process Adjustment)

  • 고용해;이성철;전상표
    • 대한안전경영과학회:학술대회논문집
    • /
    • 대한안전경영과학회 1999년도 추계학술대회
    • /
    • pp.237-246
    • /
    • 1999
  • An important problem in process adjustment using feedback is how often to sample the process and when to apply an adjustment. Schemes designed to minimize the overall cost. The cost taken the frequency with which they require observations to be made, and the resulting overall length of time between adjustment. In this article, the process adjustment which is based on the adaptive EWMA forecasts are derived. An example is presented to improve confirm standard varation through the analysis of a data series.

  • PDF

Comparison of sequential estimation in response-adaptive designs with and without covariate-adjustment

  • Park, Eunsik
    • Communications for Statistical Applications and Methods
    • /
    • 제23권4호
    • /
    • pp.287-296
    • /
    • 2016
  • Subjects on one side of the covariate population can be allocated to the inferior treatment when there is interaction between the covariate and treatment along with a response-adaptive (RA) design without covariate adjustment. An RA design allows a newly entered subject to have a better chance so that the subject is treated by a superior treatment based on cumulative information from previous subjects. A covariate-adjusted response-adaptive (CARA) is the same as RA design and additionally adjusts the allocation based on individual covariate information. A comparison has been made for the sequential estimation procedure with and without covariate adjustment to see how ignoring significantly interactive covariate affects the correct treatment allocation. Using logistic models, we present simulation results regarding the coverage probability of treatment effect, correct allocation, and stopping time.

적응적 EWMA 피드백 공정 조정 (Adaptive EWMA Feedback Process Adjustment)

  • 고용해;이성철;전상표
    • 대한안전경영과학회지
    • /
    • 제1권1호
    • /
    • pp.111-121
    • /
    • 1999
  • An important problem in process adjustment using feedback is how often to sample the process and when to apply an adjustment. Schemes are designed to minimize the overall cost. The cost is taken the frequency with which they require observations to be made, and the resulting overall length of time between adjustments. In this article, the process adjustment which is based on the adaptive EWMA forecasts is derived. An example is presented to improve the standard variation through the analysis of data series.

  • PDF

암환자의 대응양식과 불안과의 관계 (Correlation between Mental Adjustment to Cancer and Anxiety)

  • 오복자
    • 종양간호연구
    • /
    • 제9권1호
    • /
    • pp.23-30
    • /
    • 2009
  • Purpose: This study was to identify the relationship between mental adjustment to cancer and anxiety. Method: This study used a cross-sectional descriptive design. A total of 124 ambulatory cancer patients completed the Mental Adjustment to Cancer (MAC) scale and Hospital Anxiety and Depression Scale (HADS). Data were analyzed using descriptive statistics, t-test, ANOVA and Pearson correlation. Results: There was a significantly negative correlation between anxiety and fighting spirit which was adaptive adjustment to cancer (r=-0.29, p<0.001). However, anxiety had significantly positive correlation with helplessness/hopelessness (r=0.38, p<0.001), anxious preoccupation (r=0.55, p< 0.001), and fatalism (r=0.22, p<0.05) to cancer. Conclusion: Cancer patients' mental adjustment is correlated with the degree of the psychosocial distress. Anxious preoccupation and helplessness/hopelessness are the most maladaptive adjustments whereas fighting spirit is one of the most adaptive adjustment to cancer.

  • PDF

Parameter Reduction in Digital Adaptive Flight Control System for Spaceplanes

  • Togasaki, Yoshihiro;Shimada, Yuzo;Uchiyama, Kenji
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 2004년도 ICCAS
    • /
    • pp.995-1000
    • /
    • 2004
  • A digital adaptive flight control system is presented for a Japanese automatic landing flight experiment vehicle (ALFLEX). In previous adaptive control systems based on a linear-parameter-varying (LPV) form, the output behavior was excellent, while the behavior of the adjusted parameters was unsatisfactory. In the present study, to obtain a more appropriate parameter adjustment law, the relationship between the coefficient matrices in a continuous-time state equation and the coefficients of a pulse transfer function in a discrete system for conventional aircraft is investigated. As a result, it is revealed that the coefficients of the numerator can be treated as a linear function of dynamic pressure (linear-parameter-varying: LPV), while the coefficients of the denominator can be treated as constant (linear-time-invariant: LTI). From the above analysis, an improved parameter adjustment law is derived by reducing the number of the adjustment parameters. Simulation results also revealed both good output tracking and good parameter adjustment compared with the previous results.

  • PDF

과모델된 선형 시불변 이산 시간 시스템의 적응 제어법칙 (Adaptive control of overmodeled linear time-invariant discrete systems)

  • 양현석;이호신
    • 제어로봇시스템학회논문지
    • /
    • 제2권2호
    • /
    • pp.67-72
    • /
    • 1996
  • This paper presents a parameter adaptive control law that stabilizes and asymptotically regulates any single-input, linear time-invariant, controllable and observable, discrete-time system when only the upper bounds on the order of the system is given. The algorithm presented in this paper comprises basically a nonlinear state feedback law which is represented by functions of the state vector in the controllable subspace of the model, an adaptive identifier of plant parameters which uses inputs and outputs of a certain length, and an adaptive law for feedback gain adjustment. A new psedu-inverse algorithm is used for the adaptive feedback gain adjustment rather than a least-square algorithm. The proposed feedback law results in not only uniform boundedness of the state vector to zero. The superiority of the proposed algorithm over other algorithms is shown through some examples.

  • PDF

유압 서보시스템을 위한 적응제어기 설계 (The Design of Adaptive Controller for a Hydraulic Servo Motor)

  • 이상윤;신위재
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 1998년도 하계종합학술대회논문집
    • /
    • pp.231-234
    • /
    • 1998
  • In this paper, we proposed a adaptive controller which need not adjustment of the scale factor. We have verified by experimental results that applying this proposed adaptive control algorithm to a hydraulic servo system is very satisfactory.

  • PDF

아동이 지각한 어머니의 양육태도와 어머니-자녀관계가 학교생활적응에 미치는 영향 (The Effect of the Mother's Rearing Attitude and Mother-Child Relationship-as Perceived by the child on School Adjustment)

  • 김혜금
    • 대한가정학회지
    • /
    • 제50권6호
    • /
    • pp.65-75
    • /
    • 2012
  • This study was to examine the effect of the mother's rearing attitude and mother-child relationship, as perceived by the child, on adjustment to school life. The present study investigated how the mother's rearing attitude and mother-child relationship, as perceived by the child, influence school life adjustment. The participants were 300 4th grade elementary school students (173 boys and 127 girls), in Seoul. The data were analyzed using Pearson's correlation and multiple regression, by SPSS 12.0 program. The results were as follows: 1) The child who perceived the mother's rearing attitude to be more rational and democratic, was more adaptive in school life. 2) The mother-child relationship that the child perceived, had a positive relationship with the school life adjustment of the child. The child who perceived the mother-child relationship more positively, was more adaptive in school life. 3) In relationship with the teacher and school class, the mother's democratic rearing attitude, as perceived by the child, was found to be the most affecting factor. In relationship with the classmates and school rules, the mother-child relationship, as perceived by the child, was found to be the most affecting factor.

헬리콥터 주로터 블레이드 동적밸런싱 시험을 위한 조절변수 최적화 연구 (A Study on Adjustment Optimization for Dynamic Balancing Test of Helicopter Main Rotor Blade)

  • 송근웅;최종수
    • 한국소음진동공학회논문집
    • /
    • 제26권6_spc호
    • /
    • pp.736-743
    • /
    • 2016
  • This study describes optimization methods for adjustment of helicopter main rotor tracking and balancing (RTB). RTB is a essential process for helicopter operation and maintenance. Linear and non-linear models were developed with past RTB test results for estimation of RTB adjustment. Then global and sequential optimization methods were applied to the each of models. Utilization of the individual optimization method with each model is hard to fulfill the RTB requirements because of different characteristics of each blade. Therefore an ensemble model was used to integrate every estimated adjustment result, and an adaptive method was also applied to adjustment values of the linear model to update for next estimations. The goal of this developed RTB adjustment optimization program is to achieve the requirements within 2 run. Additional tests for comparison of weight factor of the ensemble model are however necessary.