• Title/Summary/Keyword: $<_+$-stable

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A study of stable output of solid-state laser through feedback control (Feedback 제어를 통한 고체 레이저의 출력특성 안정화에 관한 연구)

  • Song, K.Y.;Kwak, S.Y.;Hong, J.H.;Noh, K.K.;Kim, W.Y.;Kang, U.;Kim, H.J.
    • Proceedings of the KIEE Conference
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    • 2002.07c
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    • pp.1853-1855
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    • 2002
  • A pulsed Nd:YAG laser is used widely in many applications such as materials processing, communications, military and medical instruments. It is important to control the laser energy in those fields with using a pulsed Nd:YAG laser. In this paper, constant-frequency current resonant half-bridge inverter and feedback control circuit are used to have output stable. This laser power supply is designed and fabri which was isolated. Also, this study is used an one-chip microprocessor, SCR, current transform A stable output of this Nd:YAG laser system investigated. The tested results are described.

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On Development the Stable Learning Algorithm for Recurrent Neural Network Control System (귀환 신경망의 안정적 학습 알고리듬 개발)

  • 연정흠;원경재;정일훈;진흥태
    • Journal of the Korean Institute of Intelligent Systems
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    • v.7 no.3
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    • pp.3-11
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    • 1997
  • One of major research areas in the recurrent neural network is to develop stable learning algorithm. In this paper, the stable learning algorithm is developed by utilizing the evolutionary programming. The effectiveness of the proposed learning algorithm will be verified by simulating two d.0.f. robot manipulator.

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Postural stability test of double leg support and single limb stance (양발로 선 자세와 한발로 선 자세의 자세안정도 검사)

  • Kwon, Mi-Ji
    • Journal of Korean Physical Therapy Science
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    • v.5 no.4
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    • pp.851-860
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    • 1998
  • The purpose of this study was to quantitatively observe changes in postural stability of double leg support and single limb stance. Thirty-six healthy subjects participated in the study. Postural stability were examined using Dynamic Balance System. Each trial was 25 sec in duration. Each of 6 conditions{double leg support and single limb stance ; eyes open in stable platform, eyes closed in stable platform, eyes open in dynamic platform) evaluated effect of visual, vestibular, proprioceptive system. Center of balance found for displacement to the left along the X axis in double leg support and to the forward on left toe in single limb stance. Sway index was the lowest in double leg support with eyes open in stable platform and the higher in single limb stance with eyes closed in stance platform. We believe that reliable and valid measures should be used to determine the contributing factors of our client's postural problems so that we can design the most effective treatment possible.

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Intelligent Auto-Tuning for Adaptive Control of DC Motor System with Load Inertia of Great Variation

  • Woraphojn Khongphasook;Vipan Prijapanij;anant, Phornsuk-Ratiroch;Jongkol Ngamwiwit;Hiroshi Hirata
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.442-442
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    • 2000
  • The intelligent auto-tuning method fur a strongly stable adaptive control system of a DC motor with great load inertia variation is proposed. The stable characteristic polynomial that is designed by an optimal servo is specified for the adaptive pole placement control system. The appropriate adaptive control system can be derived, by adjusting automatically the weight of a performance criterion in optimal control by means of the fuzzy inference on the basis of the stability index.

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Stabilizing Mechanism for Methane Rich-Lean Flame (메탄 과농-희박 예혼합화염의 안정화 메커니즘)

  • Lee, Won-Nam;Seo, Dong-Kyu
    • 한국연소학회:학술대회논문집
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    • 2002.11a
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    • pp.19-24
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    • 2002
  • Recent studies of a triple flame suggested that the presence of triple point (triple line in this planar configuration) could explain the mechanisms of stable fuel-lean premixed flames with equivalence ratio lower than the flammability limit. In the present study, for better understanding of the stability mechanisms of fuel rich-lean premixed flames, the fuel-rich flames were replaced with hot coils that will provide heat flux into the fuel-lean flames. It is found that the fuel-lean premixed flames could be stabilized without any triple point (triple line): however, the equivalence ratio limit for stable fuel-lean flame in this case is higher than that of the present work with the presence of fuel-rich flames. These results demonstrate that heat flux coming from fuel-rich flames should be considered in order to properly understand the roll of a triple flame for stable fuel rich-lean flames.

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Orthogonal versus Parallel Plating for Distal Humeral Fractures

  • Moon, Jun-Gyu;Lee, Ji-Ho
    • Clinics in Shoulder and Elbow
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    • v.18 no.2
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    • pp.105-112
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    • 2015
  • In orthopedic trauma surgery, treatment of intraarticular distal humerus fractures is a challenge. With development of implants and biomechanical studies, surgical strategies with recommendations including preoperative computed tomography images, proper approaches and open reduction and internal fixation with dual plates have emerged. In addition, as an effort to provide stable fixation to permit early elbow motion, different methods of internal fixation, particularly plate configuration, have evolved. Using dual plates, either oriented parallel to each other or orthogonal, stable fixation has been achieved and satisfactory clinical outcomes have been reported. With rationales and advantages/disadvantages of each plate configuration, both techniques are selected according to surgeons' preference, and, in specific cases, one could be preferred over another. The key to successful fixation by either technique is obtaining anatomical reduction with restoration of two stable columns of the distal humerus.

MEASURES FOR STABILITY OF SLOPE ESTIMATION ON THE SECOND ORDER RESPONSE SURFACE AND EQUALLY-STABLE SLOPE ROTATABILITY

  • Park, Sung H.;Kang, Ho-Seog;Kang, Kee-Hoon
    • Journal of the Korean Statistical Society
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    • v.32 no.4
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    • pp.337-357
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    • 2003
  • This paper introduces new measures for the stability of slope estimation on the second order response surface at a point and on a sphere. As a measure of point stability of slope estimation, we suggest a point dispersion measure of slope variances over all directions at a point. A spherical dispersion measure is also proposed as a measure of spherical stability of slope estimation on each sphere. Some designs are studied to explore the usefulness of the proposed measures. Using the point dispersion measure, another concept of slope rotatability called equally-stable slope rotatability is proposed as a useful property of response surface designs. We provide a set of conditions for a design to have equally-stable slope rotatability.

Stability Analysis of Mathieu Equation by Floquet Theory and Perturbation Method (Floquet 이론과 섭동법에 의한 Mathieu Equation의 안정성해석)

  • Park, Chan Il
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.23 no.8
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    • pp.734-741
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    • 2013
  • In contrast of external excitations, parametric excitations can produce a large response when the excitation frequency is away from the linear natural frequencies. The Mathieu equation is the simplest differential equation with periodic coefficients, which lead to the parametric excitation. The Mathieu equation may have the unbounded solutions. This work conducted the stability analysis for the Mathieu equation, using Floquet theory and numerical method. Using Lindstedt's perturbation method, harmonic solutions of the Mathieu equation and transition curves separating stable from unstable motions were obtained. Using Floquet theory with numerical method, stable and unstable regions were calculated. The numerical method had the same transition curves as the perturbation method. Increased stable regions due to the inclusion of damping were calculated.

Sources of Resistance to Bacterial Wilt Found in Vietnam Collections of Pepper (Capsicum annuum) and Their Nuclear Fertility Restorer Genotypes for Cytoplasmic Male Sterility

  • Tran, Ngoc Hung;Kim, Byung-Soo
    • The Plant Pathology Journal
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    • v.28 no.4
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    • pp.418-422
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    • 2012
  • Eleven hot pepper accessions collected in Vietnam showed stable resistance to bacterial wilt as well-known resistance sources, MC4 and MC5, in repeated inoculation tests with different Ralstonia solanacearum isolates conducted from 2004 to 2010. Seven of these accessions (specifically KC981, KC1006, KC1021, KC1027, KC1045, KC1050, and KC1055) resulted in stable male sterile F1 plants in the crosses with a cytoplasmically male sterile (CMS) Chilseong (CMS-A, Srfrf ), and therefore, they were maintainers (CMS-B) with a genotype of Nrfrf. The rest (KC980, KC995, KC999, and KC1009) produced stable male fertile F1 plants in the crosses, and therefore, were restorers (CMS-C) with a genotype of N(S)RfRf. Therefore, the maintainer and restorer sources of resistance may be used in preference in breeding maternal (CMS and their maintainers) and paternal parents (restorers) for resistance to bacterial wilt, respectively, in the hybrid breeding system utilizing cytoplasmic male sterility.

TURING INSTABILITY IN A PREDATOR-PREY MODEL IN PATCHY SPACE WITH SELF AND CROSS DIFFUSION

  • Aly, Shaban
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.17 no.2
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    • pp.129-138
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    • 2013
  • A spatio-temporal models as systems of ODE which describe two-species Beddington - DeAngelis type predator-prey system living in a habitat of two identical patches linked by migration is investigated. It is assumed in the model that the per capita migration rate of each species is influenced not only by its own but also by the other one's density, i.e. there is cross diffusion present. We show that a standard (self-diffusion) system may be either stable or unstable, a cross-diffusion response can stabilize an unstable standard system and destabilize a stable standard system. For the diffusively stable model, numerical studies show that at a critical value of the bifurcation parameter the system undergoes a Turing bifurcation and the cross migration response is an important factor that should not be ignored when pattern emerges.