• 제목/요약/키워드: Regulating Structure

검색결과 170건 처리시간 0.028초

쌍롤형 박판주조기의 모델링과 적응최적제어 (Modeling and adaptive optimal control of a twin roll strip caster)

  • 김성훈;홍금식;이교일
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
    • /
    • pp.325-328
    • /
    • 1997
  • In this paper the modeling and control of a twin roll strip caster is investigated. Mathematical models for the strip casting process are obtained by analyzing five critical areas such that the molten steel level in the pool, solidification process, roll separating force and torque, roll dynamics including hydraulic actuators, and roll drive system. A two-level control strategy is proposed. At lower level, three local subsystems are independently feedback-controlled by suitable local controllers which perform well to the behaviors of each subsystem. They are a variable structure control of the molten steel level in the pool, an adaptive predictive control of the roll gap which is directly related to the strip thickness, and an $H^{\infty}$ control of the roll drive system. At higher level, all reference signals to the lower level subsystems are generated by an optimal controller in the perspective of regulating the strip thickness and roll separating force. Simulations are provided..

  • PDF

Osteopathy 의 한의학적 임상활용 방안에 관한 소고 (The Study on Clinical Application of Osteopathy to Oriental Medicine)

  • 홍서영;임형호
    • 대한추나의학회지
    • /
    • 제3권1호
    • /
    • pp.85-96
    • /
    • 2002
  • Objectives : The purpose of this study is to get knowledge about osteopathy and to applicate the osteopathy to oriental medicine. Methods: We investigated several books and literatures on osteopathy related sites explored by internet to know the general theories and present conditions of osteopathy in Korea and other countries. Results & Conclusion : 1. The principles of osteopathy are as follows. First, the human being is a dynamic unit of function. Second, the body possesses self regulating mechanisms which are self healing in nature. Third, structure and function are reciprocally interrelated. Fourth, the body rational therapy is based upon knowledge and use of the above three principles. 2. Doctors of osteopathy evaluate the musculoskeletal system to identify structural problems and to support the body's natural tendency toward health and self healing. 3. We can applicate the osteopathy to oriental clinical medicine based on interpreting the principles of osteopathy.

  • PDF

Evaluation of proteomic strategies for analyzing ubiquitinated proteins

  • Peng, Jun Min
    • BMB Reports
    • /
    • 제41권3호
    • /
    • pp.177-183
    • /
    • 2008
  • Ubiquitin is an essential, highly-conserved small regulatory protein in eukaryotic cells. It covalently modifies a wide variety of targeted proteins in the forms of monomer and polymers, altering the conformation and binding properties of the proteins and thus regulating proteasomal delivery, protein activities and localization. Mass spectrometry has emerged as an indispensable tool for in-depth characterization of protein ubiquitination. Ubiquitinated proteins in cell lysates are usually enriched by affinity chromatography and subsequently analyzed by mass spectrometry for identification and quantification. Ubiquitin-conjugated amino acid residues can be determined by unique mass shift caused by the modification. Moreover, the complex structure of polyubiquitin chains on substrates can be dissected by bottom-up and middle-down mass spectrometric approaches, revealing potential novel functions of polyubiquitin linkages. Here I review the advances and caveats of these strategies, emphasizing caution in the validation of ubiquitinated proteins and in the interpretation of raw data.

하이브리드 섬유 보강 시멘트 복합체의 인장 특성에 관한 연구 (A Study on Tension Properties on Hybrid Fiber Reinforced Cement-Based Composit)

  • 안영태;홍성걸
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
    • /
    • pp.340-343
    • /
    • 2004
  • The cement-based composites have been used for construction industry because of their economy, suitability for architecture and structure function, fire resistance, low fee of repair, easiness for acquisition. but the limited strain capacity of these makes them tension-weak, brittle, and considerable notch-sensitive. As one of solution, FRC(fiber reinforced concrete) have been investigated for regulating weakness of the cement-based composites. In these day different fiber types are proposed for better performance such as HFRC(hybrid fiber reinforced concrete). This study shows experimental results to search the ultimate strength, the ultimate mean strain, and the tension toughness of HFRC. The tension toughness is proportional to the amount of steel fiber and carbon fiber. In this experimental program we kept the total of steel fiber and carbon fiber as $1.0\%,\;1.5\%$, respectively.

  • PDF

NMR Characterization of Oxidized Form of Human 8-kDa Dynein Light Chain

  • Shin, Jae-Sun;Jeong, Woo-Jin;Chi, Seung-Wook
    • 한국자기공명학회논문지
    • /
    • 제14권2호
    • /
    • pp.127-133
    • /
    • 2010
  • Redox-dependent conformational change of human 8-kDa Dynein light chain (LC8) plays important role in regulating NF-${\kappa}B$ signaling pathway. In this study we characterized the structural states of the oxidized and reduced forms of LC8 by using NMR spectroscopy. The $^1H-^{15}N$ 2D HSQC spectra of oxidized LC8 indicated that no significant change in tertiary structure of LC8 occurred upon oxidation. The chemical shift perturbations of LC8 upon oxidation suggest a redox-dependent quaternary structural change.

Adaptive cutting force controller for milling processes by using AC servodrive current measurements

  • Kim, Jongwon
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
    • /
    • pp.840-843
    • /
    • 1996
  • This paper presents an adaptive cutting force controller for milling process, which can be attached to most commercial CNC machining centers in a practical way. The cutting forces of X,Y and Z axes measured indirectly from the use of currents drawn by AC feed-drive servo motors. A typical model for the feed-drive control system of a horizontal machining center is developed to analyze cutting force measurement from the drive motor. The pulsating milling forces can be measured indirectly within the bandwidth of the current feedback control loop of the feed-drive system. It is shown that indirectly measured cutting force signals can be used in the adaptive controller for cutting force regulation. The robust controller structure is adopted in the whole adaptive control scheme. The conditions under which the whole scheme is globally convergent and stable are presented. The suggested control scheme has been implemented into a commercial machining center, and a series of cutting experiments on end milling and face milling processes are performed. The adaptive controller reveals reliable cutting force regulating capability under various cutting conditions.

  • PDF

유체력을 이용한 직동식 비례 유량 조절 밸브에 관한 연구 (A Study on a Direct-Type Proportional Flow Control Valve Utilizing Flowforces)

  • 배상기;현장환;이정오
    • 한국정밀공학회지
    • /
    • 제15권4호
    • /
    • pp.68-75
    • /
    • 1998
  • A one-stage direction and flow control valve was studied theoretically and experimentally. A direction and flow control valve maintains a constant flow rate by changing the spool-orifice area under the variation of valve pressure drop, since the spool-orifice area is varied by the action of flowforces on the spool. A direction and flow control valve has the advantage of simple and low-cost structure compared to a conventional flow control valve utilizing a pressure regulating spool which regulates the pressure drop caused by flow through the metering orifice. The static and dynamic characteristics of a one-stage direction and flow control valve was analyzed. Experimental results on the flow control characteristics of the manufactured valve show satisfactory agreement with simulation results.

  • PDF

Fragile X Mental Retardation Protein in Learning-Related Synaptic Plasticity

  • Mercaldo, Valentina;Descalzi, Giannina;Zhuo, Min
    • Molecules and Cells
    • /
    • 제28권6호
    • /
    • pp.501-507
    • /
    • 2009
  • Fragile X syndrome (FXS) is caused by a lack of the fragile X mental retardation protein (FMRP) due to silencing of the Fmr1 gene. As an RNA binding protein, FMRP is thought to contribute to synaptic plasticity by regulating plasticity-related protein synthesis and other signaling pathways. Previous studies have mostly focused on the roles of FMRP within the hippocampus - a key structure for spatial memory. However, recent studies indicate that FMRP may have a more general contribution to brain functions, including synaptic plasticity and modulation within the prefrontal cortex. In this brief review, we will focus on recent studies reported in the prefrontal cortex, including the anterior cingulate cortex (ACC). We hypothesize that alterations in ACC-related plasticity and synaptic modulation may contribute to various forms of cognitive deficits associated with FXS.

고속 팬터그래프의 새로운 동적 모형 및 외란관측기를 이용한 제어기 설계 (Modelling of High-Speed Pantograph and Controller Design Using Disturbance Observer)

  • 조남훈;이강현
    • 전기학회논문지
    • /
    • 제56권12호
    • /
    • pp.2233-2239
    • /
    • 2007
  • The pantograph-catenary system is one of important components for high-speed rail system that are powered electrically. Electrical power is delivered from a catenary structure to the train via a pantograph and thus it is very important to regulate the contact force between catenary and pantograph. Although a lot of research results for active pantograph have been reported, most of them have made an unrealistic assumption that the catenary displacement is constant with respect to the time. In this paper, we present a new pantograph model that regards the catenary displacement as an unknown disturbance input. Moreover, a disturbance observer based controller is proposed to remove the effect of disturbance, i.e., the catenary displacement variation. The computer simulation result shows that the substantial improvement in regulating the contact force can be achieved by the proposed controller.

Structures of proteases for ubiqutin and ubiquitin-like modifiers

  • Ha, Byung-Hak;Kim, Eunice Eun-Kyeong
    • BMB Reports
    • /
    • 제41권6호
    • /
    • pp.435-443
    • /
    • 2008
  • Post-translational modifiers can alter the function of proteins in many different ways. The conjugation of ubiquitin (Ub) and ubiqutin-like modifiers (Ubls) to proteins has been shown to be especially crucial in regulating a variety of cellular processes including the cell cycle, growth control, quality control, localization and many more. It is a highly dynamic process and involves a number of enzymes called E1, E2 and E3. Ub and Ubls are removed from the target proteins by deubiquitinating enzymes (DUBs) or Ubl-specific proteases (ULPs), thereby deconjugation can act as an additional level of control over the ubiquitin-conjugation system. In addition, DUBs and ULPs are responsible for activating Ub and Ubls from their inactive corresponding precursor forms. Here we review recent progress in molecular details of these deconjugating enzymes of Ubls.