• Title/Summary/Keyword: simple system

검색결과 9,682건 처리시간 0.033초

MBR을 이용한 실용적 공간 데이터 관리 (A Practical Approach to Spatial Object Indexing Using Minimum Bounding Rectangles)

  • 이재호
    • 한국정보과학회:학술대회논문집
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    • 한국정보과학회 1999년도 가을 학술발표논문집 Vol.26 No.2 (1)
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    • pp.177-179
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    • 1999
  • We present a simple and efficient spatial object indexing scheme based on the minimum bounding rectangles (MBR) of the objects for use in applications in geographic information system (GIS). We also provide the rationale behind the simple indexing scheme instead of other complex hierarchical indexing approaches such as the R-tree and its variants.

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Simple modification of anthracene for the blue emitting materials

  • Kim, Si Hyun;Lee, Seung Hee
    • 한국응용과학기술학회지
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    • 제34권1호
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    • pp.101-107
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    • 2017
  • Anthracene has been a motive molecule for the blue-emitting materials in OLED. Since the blue emission needs big band gap between HOMO and LUMO, the blue-emitting materials are rare. In this paper, some anthracene derivatives containing simple aryl groups are synthesized and characterized. Regardless of the substituents the absorption and the emission bands are similar to each other and similar to the derivatives with the bulky silyl groups. The thermal and the CIE tests imply that among the tested 9-(2-naphthyl)-10-phenylanthracene is most promising for the diode. The material for the emission layer has to be investigated, which is simple to be prepared as well as good in the electrical and the thermal properties.

Analysis of a shimming aircraft NLG controlled by the modified simple adaptive control

  • Alaimo, Andrea;Orlando, Calogero
    • Advances in aircraft and spacecraft science
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    • 제7권5호
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    • pp.459-473
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    • 2020
  • The aircraft nose landing gear (NLG) can suffer of an unstable vibration called shimmy that is responsible of discomfort and of fatigue stress on the gear strut components. An adaptive controller is proposed in this paper to cope with the aforementioned problem. It is based on a method called Modified Simple Adaptive control (MSAC) which is able of governing the NLG motion by using a feedback signal that relies on just one output of the plant. The MSAC only asks for the passivity of the controlled plant. With this aim, a parallel feedforward compensator is employed in this work to let the system satisfies the almost strictly passivity (ASP) requirements. The nonlinear equations that govern the aircraft NLG shimmy vibration behavior are used to analyzed the controlled system transient response undergoing an initial disturbance and taking into account different taxiing speed values.

Stochastic response spectra for an actively-controlled structure

  • Mochio, Takashi
    • Structural Engineering and Mechanics
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    • 제32권1호
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    • pp.179-191
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    • 2009
  • A stochastic response spectrum method is proposed for simple evaluation of the structural response of an actively controlled aseismic structure. The response spectrum is constructed assuming a linear structure with an active mass damper (AMD) system, and an earthquake wave model given by the product of a non-stationary envelope function and a stationary Gaussian random process with Kanai-Tajimi power spectral density. The control design is executed using a linear quadratic Gaussian control strategy for an enlarged state space system, and the response amplification factor is given by the combination of the obtained statistical response values and extreme value theory. The response spectrum thus produced can be used for simple dynamical analyses. The response factors obtained by this method for a multi-degree-of-freedom structure are shown to be comparable with those determined by numerical simulations, demonstrating the validity and utility of the proposed technique as a simple design tool. This method is expected to be useful for engineers in the initial design stage for structures with active aseismic control.

A simple and rapid approach to modeling chromium breakthrough in fixed bed adsorber

  • Chu, Khim Hoong
    • Advances in environmental research
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    • 제7권1호
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    • pp.29-37
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    • 2018
  • A simple mathematical model for predicting fixed bed adsorption dynamics is described. The model is characterized by a linear adsorption isotherm and a linear driving force expression for mass transfer. Its analytic solution can be approximated with an algebraic equation in closed form which is easily evaluated by spreadsheet computation. To demonstrate one application of the fixed bed model, a previously published adsorption system is used as a case study in this work. The adsorption system examined here describes chromium breakthrough in a fixed bed adsorber packed with imidazole functionalized adsorbent particles and is characterized by a nonlinear adsorption isotherm. However, the equilibrium behavior of the fixed bed adsorber is in essence governed by a linear adsorption isotherm due to the use of a low influent chromium concentration. It is shown that chromium breakthrough is predicted reasonably well by the fixed bed model. The model's parameters can be easily extracted from independent batch experiments. The proposed modeling approach is very simple and rapid, and only Excel is used for computation.

모터 동역학식을 고려한 유연 연결 로봇의 간단한 적응 제어에 관한 연구 (A Study on Simple Adaptive Control of Flexible-Joint Robots Considering Motor Dynamics)

  • 유성진;최윤호;박진배
    • 제어로봇시스템학회논문지
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    • 제14권11호
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    • pp.1103-1109
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    • 2008
  • Since the flexible joint robots with motor dynamics are represented by the fifth-order nonlinear sγstem, it is difficult and complex to design the controller for electrically driven flexible-joint (EDFJ) robots. In this paper, we propose a simple adaptive control method to solve this problem. It is assumed that the model uncertainties of the robots dynamics, joint flexibility, and motor dynamics are unknown. For the simple control design, the dynamic surface design method is applied, and all uncertainties in the robot and motor dynamics are compensated by using the adaptive function approximation technique. It is proved that all signals in the controlled closed-loop system are uniformly ultimately bounded. Simulation results for three-link EDFJ manipulators are provided to validate the effectiveness of the proposed control system.

유연빔의 충격응답에 대한 단순 피드포워드 능동제어 실험 및 성능분석 (Experiment of a Simple Feed-forward Active Control Method for the Shock Response of a Flexible Beam and Performance Analysis)

  • 표상호;신기홍
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2006년도 춘계학술대회논문집
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    • pp.634-639
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    • 2006
  • Active control method is applied to a flexible beam excited by a shock impulse in order to reduce the residual vibrations after the shock event. It is assumed that the shock input can be measured and is always occurred on the same point of the beam. If the system is well identified and the corresponding inverse system is designed reliably, it has shown that a very simple feed-forward active control method may be applied to suppress the residual vibrations without using error sensors and adaptive algorithm. Both numerical simulations and experimental results show a promising possibility of applying to a practical problem. Also, the performance of the method is examined by considering various practical aspects : shock duration, shock magnitude, and control point.

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웹 기반 원격 액츄에이터 제어 시스템 구현 (Implementation of Actuator Control System based on Web)

  • 배병채;정동민;이영동
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2016년도 춘계학술대회
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    • pp.570-572
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    • 2016
  • 최근 사물인터넷에 대한 관심이 높아지고 있으며, 여러 분야에서 사물인터넷을 접목한 응용 사례들이 늘어나고 있다. 본 논문에서는 웹을 통해 다양한 사물들의 제어를 위해 서버는 파이썬을 기반으로 한 SimpleHTTPServer를 활용하여 구현하였으며, 클라이언트에서는 웹페이지 메시지 전송 방식중 하나인 POST 방식을 이용하여 웹 서버를 경유하여 원격지 액츄에이터 제어 시스템을 구현하였다.

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서보 시스템을 위한 간단한 제어기 보드의 구현 (Implementation of Simple Controller Board for the Servo System)

  • 최광순;이용구;엄기환;손동설
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1995년도 하계학술대회 논문집 B
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    • pp.738-741
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    • 1995
  • This disseration realized the simple digital controller board using ${\mu}$-PD 70320 microprocessor has characteristics that are low cost, simple hardware organization, convenient and interchangeable with the 8086 for the servo system. We gave the control algorithm such as PD control. Self tuning adaptive control and Fuzzy control to the realized controller board and made a new real number data type for a high accuracy control. Users can select of suitable for the control algorithim. In the result of simulation and experiment shown a good performance.

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