• 제목/요약/키워드: disturbance system

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Physical Properties of Transiting Planetary System TrES-3

  • Lee, Jae-Woo;Youn, Jae-Hyuck;Kim, Seung-Lee;Lee, Chung-Uk;Koo, Jae-Rim;Park, Byeong-Gon
    • 천문학회보
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    • 제35권2호
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    • pp.65.2-65.2
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    • 2010
  • We present four new transits of the planetary system TrES-3 observed between 2009 May and 2010 June. Among those, the third transit by itself indicates possible evidence for brightness disturbance, which could originate from a starspot or an overlapping double transit. A total of 107 transit times, including our measurements, were used to determine the improved ephemeris with a transit epoch of $2454185.910950\pm0.000073$ HJED (Heliocentric Julian Ephemeris Date) and an orbital period of $1.30618698\pm0.00000016$ d. We analyzed the transit light curves using the JKTEBOP code and adopting the quadratic limb-darkening law. In order to derive the physical properties of the TrES-3 system, the transit parameters are combined with the empirical relations from eclipsing binary stars and stellar evolutionary models, respectively. The stellar mass and radius obtained from a calibration using $T_{eff}$, log $\rho$ and [Fe/H] are in good agreement with those from the isochrone analysis within the uncertainties. We found that the exoplanet TrES-3b has a mass of $1.93\pm0.07\;M_{Jup}$, a radius of $1.30\pm0.04\;R_{Jup}$, a surface gravity of $28.2\pm1.1\;m\;s^{-1}$, a density of $0.82\pm0.06\;\rho_{Jup}$, and an equilibrium temperature of $1641\pm23K$.

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자동피킹 시스템 구동용 선형 유도 모터 드라이브 설계 및 적분형 가변구조 제어 기반의 강인 위치 제어기 설계 (Design of Linear Induction Machine Drive and Robust Position Controller based on Integral Variable Structure Scheme for Automatic Picking System)

  • 최정현;유동상;김경화
    • 한국지능시스템학회논문지
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    • 제23권6호
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    • pp.511-518
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    • 2013
  • 고 정밀도와 고 속응성의 물류 이송을 위한 자동피킹 시스템 (Automatic Picking System; APS) 구동용 선형 유도 모터 드라이브의 설계 및 강인한 위치 제어 기법이 제안된다. 모델 불확실성에 대한 강인한 위치 제어기 설계를 위해서 적분형 가변구조 제어 기법이 고려된다. APS의 외란추력, 질량 및 마찰계수 등의 기계적 파라미터 변화는 위치 제어 성능에 직접적 영향을 주며 이러한 불확실성 하에서도 강인한 위치 응답 성능을 보유하는 위치 제어기가 설계된다. 선형 유도 모터의 모델을 위한 Simulink 라이브러리가 상태방정식으로부터 개발되며 이를 활용한 Matlab - Simulink 기반의 비교 시뮬레이션을 통해 제안된 방식이 강인한 위치 응답 성능을 가지며 고 정밀도와 고 속응성을 요구하는 APS에 적합함이 입증된다.

미세 다공성 과립을 이용한 탐스로신의 방출제어 (Controlled Release of Tamsulosin from Nanopore-Forming Granules)

  • 서성미;이현숙;이재휘;이하영;이봉;이해방;조선행
    • Journal of Pharmaceutical Investigation
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    • 제36권1호
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    • pp.39-44
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    • 2006
  • Tamsulosin or a salt thereof such as its hydrochloride salt has been known to have an adrenaline ${\alpha}$ receptor blocking action for urethra and prostate areas. It has been widely used as a drug which lowers the prostate pressure and improves urinary disturbance accompanied by prostate-grand enlargement, thus for the treatment of prostatic hyperplasia. To avoid dose-dependent side effects of tamsulosin upon oral administration, the development of sustained-release delivery system is essentially required, that can maintain therapeutic drug levels for a longer period of time. The aim of this study was therefore to formulate sustained-release tamsulosin granules and assess their formulation variables. We designed entric coated sustained-release tamsulosin granules for this purpose. Nano-pores in the outer controlled release membrane were needed in order to obtain initial tamsulosin release even in an acidic environment such as gastric region. In our sustained release osmotic granule system, hydroxypropylmethylcellulose in a drug-containing layer was used as a rate controller. The drug-containing granules were coated with hydroxypropylmethylcellulose phthalate (HPMCP) and Eudragit, along with glycerol triacetate as an aqueous nano-pore former. The release of tamsulosin depended heavily on the type of Eudragit such as RS, RL, NE 30D, used in the formulation of controlled release layer. These results obtained clearly suggest that the sustained-release oral delivery system for tamsulosin could be designed with satisfying drug release profile approved by the Korean Food and Drug Administration.

이산형선형추적(離散型線型追跡)에 의한 제약저수지계(制約貯水池系)의 최적(最適) 제어 (Optimal Control of the Constrained Reservoir System by the Discrete Linear Tracking)

  • 권오훈;선우중호
    • 대한토목학회논문집
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    • 제5권3호
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    • pp.1-12
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    • 1985
  • 저수지계(貯水池系)의 최적운영(最適運營)은 다차원문제(多次元問題)로서 일반적으로 O.R. 기법(技法)으로 해를 구할 수 있다. 본(本) 연구(硏究)에서는 선형추적리론(線型追跡理論)을 이산화(離散化)하여 2점(點) 경계치문제(境界値問題)를 풀었다. 이 이론의 적용에는 두가지 문제가 제기되는데 첫째, 추적(追跡)을 위한 기준(基準)이 미지수(未知數)이므로 무제약(無制約) 조건(條件)의 최적률(最適律)을 반복 적용하여 수렴치(收斂値)를 구하여 이로부터 추적기준(追跡基準)을 산출했다. 둘째, 상태 및 제어벡터의 제약조건(制約條件)의 처리는 Pontryagin의 최소원리(最小原理)로 해결하였다.

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반도체 생산에서 진동 제어를 위한 전자기 에어 스프링 (An Electro-magnetic Air Spring for Vibration Control in Semiconductor Manufacturing)

  • 김형태;김철호;이강원;이규섭;손성완
    • 한국소음진동공학회논문집
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    • 제20권12호
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    • pp.1128-1138
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    • 2010
  • 정밀 방진에서 전형적인 문제로 고하중으로 인한 저주파 공진 특성이 있다. 전자기 에어 스프징은 진동 제어 장치이자 능동형 방진 장치이다. 이 연구에서 전자기 에어 스프링은 반도체 생산을 위한 저주파 공진을 제거하는 것을 목적으로 한다. 능동형 방진 장치로 기계 및 전가 부분은 2.5톤의 하 중에 작동되도록 설계하였다. 전자기 스프링은 탄성 공압 챔버 내에 공기압을 이용하여 띄우고, 전자기 된 시스템에 의하면 공진 주파수 영역에서 제어 시간 및 최고 피크가 상당히 줄어들었고, 그 결과 피동형 시스템 상의 고유 진동에 의해 발생되는 공진을 피할 수 있음을 보였다.

생태정보의 공유를 위한 생태정보 포털서비스 (EcoBank) 구축 및 활용 방안 (Development and Applications of Ecological Data Portal Service (EcoBank) for Sharing Ecological Information of Korea)

  • 성선용;권용수;김기동
    • 생태와환경
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    • 제51권3호
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    • pp.212-220
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    • 2018
  • Ecological and ecosystem database is becoming very necessary to understand origins and relationship between human and nature and also to minimize disturbance caused by human activities. An ecological information portal can play important roles as a computing system to collect knowledge, distributed research findings and separated data from researchers. In this study, we designed and developed ecological information portal service (EcoBank 1.0) for collecting and providing ecological information for diverse classes of stakeholders. To reach the goal, we had reviewed related and comparable ecological database portals to design conceptual structure of EcoBank system including database management framework. Then, we developed some functions of ecosystem analysis for each stake-holders (researchers, general public and policy makers). As a result of this study, we successfully designed of EcoBank system covering the functions of Digital Object Identifier(DOI) publishing and data quality management process. Also, we (1) applied ecological indices for calculating biodiversity by administrative boundary for policy makers, (2) provided statistical information of econature map for general public and distribution characteristics of species for researchers. To make a successful establishment of EcoBank, we have to collect and build up related database and offer various and reliable ecological data consistently. We expect that the successful construction of EcoBank will help not only to accomplish sustainable development goals but also to raise the welfare of ecosystem in Korea.

이중초음파에서 관찰된 경동맥갈퀴막: 4례 (Carotid Web in Duplex Sonography: 4 Cases)

  • 한민호;서강식;최정혜
    • 대한임상검사과학회지
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    • 제52권1호
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    • pp.78-82
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    • 2020
  • 경동맥갈퀴막은 전체 뇌졸중 환자에서 매우 드물게 발견되는 희귀한 질환이며, 원인불명뇌졸중(cryptogenic stroke) 환자에서 다른 뇌졸중 아형에 비해 빈번하게 관찰되는 특징이 있다. 혈관 내막의 섬유근이형성증(fibromuscular dysplasia)이 경동맥갈퀴막의 원인으로 알려져 있고, 경동맥갈퀴막은 혈관 내 혈류의 교란을 야기하여 혈전을 만들고 색전성 뇌졸중을 일으킬 수 있다고 보고되었다. 경동맥갈퀴막은 섬유근이형성증으로 인해 비교적 딱딱한 섬유성 구조물이 혈관의 내강으로 뻗어 나오게 되고, 이중초음파에서 이중 속공간(double lumen)을 만들기 때문에 경동맥박리와 혼동하기 쉽다. 또한, 경동맥갈퀴막은 갈퀴막(web) 모양이기 때문에 궤양성죽상판과 같은 다른 경동맥질환과 혼동할 우려가 있다. 하지만, 경동맥갈퀴막은 시작 부위가 굵었다가 끝으로 갈수록 가늘어지는 경향이 있고, 박동성 혈류에 의한 펄럭임이 없는 것이 특징이다. 따라서, 본 연구는 총 4개의 경동맥갈퀴막 증례를 가지고, 질환에 대한 전반적인 설명과 함께 이중초음파의 특징적인 소견에 집중하여 보고하고자 한다.

세명대학교 부속한방병원 야간 진료실 내원환자의 실태분석 (Survey on the Actual Conditions of Patients in Semyung University Attached Oriental Medical Hospital Night Clinic.)

  • 민웅기;남창규
    • 대한한의학회지
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    • 제20권4호
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    • pp.50-61
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    • 2000
  • This study on the visits of the oriental medical night clinic of patients, was made to be used as reference data by examining and analyzing statistically the many actual conditions of patients who had been visited in Semyung University Attached Oriental Medical Hospital during the period from April, 1998 to March, 1999. The purpose of this survey was to understand the characteristics of patients, to evaluate the roles of Night Clinic of oriental medical hospital, and contribute to the systemic and efficient management of night clinic service. The results obtained were as follows: I. Distribution of sex: male 53% (421 cases), female 47% (379 cases) 2. The age distribution of patients showed the highest in under ten, followed by the thirties and fifties, forties and twenties in order. 3. The monthly distribution of patients showed the highest in October 1998, followed by May 1998 and February 1999 in order. 4. The daily distribution of patients showed the highest in Sunday, followed by Saturday, Monday, Friday and Tuesday in order. 5. The regional distribution revealed the highest in Jecheon with 76% of all patients, followed by Danyang in order. 6. The distribution of arrival time showed the highest in 7:00 pm~0:00 am (27%), followed by 5:30 pm~7:00 pm (23%) in order. 7. The admission rate in patients was 17%. Among them direct visiting rate was 85%. Circulatory systemic disease was the highest. 8. The highest incidences by disease were of motor system with 48% (394cases), followed by diseases in circulatory system with 19% (l48cases). The majority of the patients 67% was connected with two diseases. 9. The chief complaint of pediatric diseases was febrile seizure with 64% (32cases), digestive disease was abdominal pain with 44% (90cases), circulatory diseases was motor disturbance with 43% (83cases), motor system disease was leg pain with 37% (l19cases), respiratory disease was fever with 46% ( 41 cases). 10. In the treatment method, a major portion of treatment methods was acupuncture treatment with 32% (373cases), followed by acupuncture & herbal medicine treatment with 23% (275cases). The most commonly used herbal medicines were Hangsapyunguisan(l6%) and Ojeoksan(l4%).

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시간지연을 갖는 이산 비선형 마코비안 점프 시스템의 H 퍼지 제어 (H Fuzzy Control for Discrete-Time Nonlinear Markovian Jump Systems with Time Delay)

  • 이갑래;이경희
    • 한국지능시스템학회논문지
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    • 제19권6호
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    • pp.779-786
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    • 2009
  • 본 논문에서는 시간지연을 가지는 이산 비선형 마코비안 점프 시스템의 $H_{\infty}$ 퍼지 제어 문제를 다룬다. Takgi-Sugeno 퍼지 모델을 이용하여 마코비안 점프 파라미터를 갖는 시간 지연 비선형 시스템을 마코비안 점프 퍼지 시스템으로 나타내고, 이에 대한 제어기를 설계한다. 확률 퍼지-리아프노프(Lyapunov) 함수를 이용하여 안정성 및 $H_{\infty}$ 성능을 해석하고 이 함수를 이용하여 폐루프 시스템이 안정하며 $H_{\infty}$ 성능 조건을 만족하는 조건식을 유도한다. 확률 퍼지-리아프노프 함수는 시스템 모드에 따라 변하는 함수이다. 유도된 조건식으로부터 제어기 존재 조건을 선형행렬부등식으로 나타내며, 제어기는 선형행렬부등식으로부터 바로 구할 수 있다. 수치적 예제 및 컴퓨터 시뮬레이션을 통하여 제안된 방법의 타당성을 보인다.

300MW급 IGCC를 위한 건식 분류층 석탄 가스화 공정의 동적 상태 모사 (The Process Simulation of Entrained Flow Coal Gasification in Dynamic State for 300MW IGCC)

  • 김미영;주용진;최인규;이중원
    • 한국수소및신에너지학회논문집
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    • 제21권5호
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    • pp.460-469
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    • 2010
  • To develop coal gasfication system, many studies have been actively conducted to describe the simulation of steady state. Now, it is necessary to study the gasification system not only in steady state but also in dynamic state to elucidate abnormal condition such as start-up, shut-down, disturbance, and develop control logic. In this study, a model was proposed with process simulation in dynamic state being conducted using a chemical process simulation tool, where a heat and mass transfer model in the gasifier is incorporated, The proposed model was verified by comparison of the results of the simulation with those available from NETL (National Energy Technology Laboratory) report under steady state condition. The simulation results were that the coal gas efficiency was 80.7%, gas thermal efficiency was 95.4%, which indicated the error was under 1 %. Also, the compositions of syngas were similar to those of the NETL report. Controlled variables of the proposed model was verified by increasing oxygen flow rate to gasifier in order to validate the dynamic state of the system. As a result, trends of major process variables were resonable when oxygen flow rate increased by 5% from the steady state value. Coal flow rate to gasifier and quench gas flow rate were increased, and flow rate of liquid slag was also increased. The proposed model in this study is able to be used for the prediction of gasification of various coals and dynamic analysis of coal gasification.