• Title/Summary/Keyword: new horizon

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Multiple fibro-osseous lesions of the jaws: A report of a rare case with a literature review

  • Makkad, Ramanpal Singh;Naidu, Giridhar S.;Nagi, Ravleen;Sagtani, Alok;Patil, Santosh;Shrivastava, Swatantra
    • Imaging Science in Dentistry
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    • v.51 no.4
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    • pp.461-466
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    • 2021
  • Fibro-osseous lesions are a poorly defined category of conditions affecting the jaws and craniofacial bones, and include developmental lesions, reactive or dysplastic lesions, and neoplasms. Fibrous dysplasia and ossifying fibroma are the 2 main types of fibro-osseous lesions affecting the jaw, and ossifying fibroma is a true benign neoplasm of the bone-forming tissues with several well-recognized variants ranging from innocuous to extensively aggressive lesions. However, multiple simultaneous fibro-osseous lesions of the jaw bones involving all quadrants are exceedingly rare. One such case diagnosed by conventional radiography and computed tomography is discussed here.

Receding horizon tracking controller and its stability properties

  • Kwon, Wook-Hyun;Byun, Dae-Gyu
    • 제어로봇시스템학회:학술대회논문집
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    • 1987.10a
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    • pp.801-806
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    • 1987
  • The receding horizon tracking control for the discrete time invariant systems is presented in this paper. This control law is derived with the receding horizon concept from the standard tracking problems. Stability properties of this control law are analyzed. It is shown that there exists a finite horizon index for which the closed loop systems are always asymptotically stable. The receding horizon tracking control is a kind of predictive control and will add a new clan to many existing predictive controls, with which some comparisons are made.

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Receding Horizon FIR Parameter Estimation for Stochastic Systems

  • Lee, Kwan-Ho;Han, Soo-Hee;Lee, Changhun;Kwon, Wook-Hyun
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.159.1-159
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    • 2001
  • A new time-domain FIR parameter estimation called the receding horizon least square estimation (RHLSE) is suggested for stochastic systems by combining the well known least square estimation with the receding horizon strategy. It can be always obtained without the requirement of any \textit{a priori} information about the horizon initial parameter. A fast algorithm for the suggested estimation is also presented which is remarkable in the view of computational advantage and simple implementation. It is shown that the proposed estimation is robust against temporary modeling uncertainties due to their FIR structure through simulation studies.

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A Note on Age Replacement Policy of Used Item at Age $t_0$

  • Lim, J.H.
    • International Journal of Reliability and Applications
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    • v.10 no.1
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    • pp.33-42
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    • 2009
  • In most of literatures of age replacement policy, the authors consider the case that a new item starts operating at time zero and is to be replaced by new one at time T. It is, however, often to purchase used items because of the limited budget. In this paper, we consider age replacement policy of a used item whose age is $t_0$. The mathematical formulas of the expected cost rate per unit time are derived for both infinite-horizon case and finite-horizon case. For each case, we show that the optimal replacement age exists and is finite and investigate the effect of the age of the used item.

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Kalman filters with moving horizons (칼만필터의 응용에 관한 연구)

  • 권욱현;고명삼;박기헌
    • 전기의세계
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    • v.29 no.7
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    • pp.471-477
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    • 1980
  • This paper deals with a modified Kalman filter. An approaching horizon with a suitable initial condition will be considered, which is a little different from the classical Kalman filter. It will be shown in this paper that the new filter with approaching horizons is not only easy to computer but also possesses asymptotic stability properties. Thus this new estimatoris an excellent compromise between the ease of computation and the strict sense of optimality. When this estimator is used for the standard problem, the error covariance bound has been obtained. It is shown that the new estimator can be used as a suboptimal estimator which has a stability property. It is also demonstrated that the steady state Kalman filter can be obtained from the moving horizon estimator by taking the horizon parameter as infinity.

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Receding Horizon $H_{\infty}$ Predictive Control for Linear State-delay Systems

  • Lee, Young-Sam
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.2081-2086
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    • 2005
  • This paper proposes the receding horizon $H_{\infty}$ predictive control (RHHPC) for systems with a state-delay. We first proposes a new cost function for a finite horizon dynamic game problem. The proposed cost function includes two terminal weighting terns, each of which is parameterized by a positive definite matrix, called a terminal weighting matrix. Secondly, we derive the RHHPC from the solution to the finite dynamic game problem. Thirdly, we propose an LMI condition under which the saddle point value satisfies the well-known nonincreasing monotonicity. Finally, we shows the asymptotic stability and $H_{\infty}$-norm boundedness of the closed-loop system controlled by the proposed RHHPC. Through a numerical example, we show that the proposed RHHC is stabilizing and satisfies the infinite horizon $H_{\infty}$-norm bound.

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a survey and some new stability results

  • Byun, Dae-Gyu;Kwon, Wook-Hyun
    • 제어로봇시스템학회:학술대회논문집
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    • 1987.10a
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    • pp.734-740
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    • 1987
  • Various kinds of predictive control design methods such as MAC(Model Algorithmic Control), DMC(Dynamic Matrix Control), MC(Extended Horizon Adaptive Control), GPC(Generalized Predictive Control), RHTC(Receding Horizon Tracking Controller), and PVC(PreView Controller) are surveyed and compared in this paper. In addition, stability properties of these control laws known to date are summarized and some new stability results are presented.

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Condition based age replacement policy of used item

  • Lim, J.H.;Lipi, T.F.;Zuo, M.J.
    • International Journal of Reliability and Applications
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    • v.12 no.2
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    • pp.131-143
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    • 2011
  • In most of literatures of age replacement policy, the authors consider the case that a new item starts operating at time zero and is to be replaced by new one at time T. It is, however, often to purchase used items because of the limited budget. In this paper, we consider age replacement policy of a used item whose age is $t_0$. The mathematical formulas of the expected cost rate per unit time are derived for both infinite-horizon case and finite-horizon case. For each case, we show that the optimal replacement age exists and is finite and investigate the effect of the age of the used item.

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On the Selection of Demand Used in Planning for the Distribution Networks

  • Jun Geol, Baek
    • Journal of the Korea Safety Management & Science
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    • v.6 no.1
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    • pp.135-146
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    • 2004
  • This paper first addresses a distribution planning method on centrally controlled supply chain. The distribution channels are assumed to be network of arborescence form. For such distribution networks, this study proposes a distribution planning scheme when the demands for retail sites are provided for a given planning horizon. As the planning horizon rolls forward, for a new horizon, forecasted demand distributions of periods in the horizon are updated. An idea of controlling customer service level by the selection of demand to be used in the planning (Demand Used in Planning, DUP) from the forecasted values is also discussed.

Receding Horizon Finite Memory Controls for Output Feedback Controls of Discrete-Time State Space Models

  • Han, Soo-Hee;Kwon, Wook-Hyun
    • 제어로봇시스템학회:학술대회논문집
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    • 2003.10a
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    • pp.1896-1900
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    • 2003
  • In this paper, a new type of output feedback control, called a receding horizon finite memory control (RHFMC), is proposed for stochastic discrete-time state space systems. Constraints such as linearity and finite memory structure with respect to an input and an output, and unbiasedness from the optimal state feedback control are required in advance. The proposed RHFMC is chosen to minimize an optimal criterion with these constraints. The RHFMC is obtained in an explicit closed form using the output and input information on the recent time interval. It is shown that the RHFMC consists of a receding horizon control and an FIR filter. The stability of the RHFMC is investigated for stochastic systems.

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