• 전자공학회논문지 IE
• /
• 제44권4호
• /
• pp.35-40
• /
• 2007

본 논문은 엘리베이터의 분산 제어 시스템을 수학적으로 모델링 하여 이 모델을 기반으로 미리 정의된 제어 목적 하에서 보다 안정되고 향상된 성능을 보이는 제어 알고리즘을 설계하는 것을 목적으로 한다. 또한 승강장 요구 응답 시간 추정과 실제 값을 분석하였다.

• 한국정밀공학회지
• /
• 제20권2호
• /
• pp.94-103
• /
• 2003

In case of environment requiring safety such as human body and requiring flexible shape, a conventional mechanical actuator system does not satisfy requirements. Therefore, in order to solve these problems. a research of various smart material such as EAP (Electro Active Polymer), EAC (Electro Active Ceramic) and SMA (Shape Memory Alloy) is in progress. Recently, the highest preferring material among various smart material is EP (Electrostictive Polymer), because it has very fast response time, powerful force and large displacement. The previous researches have been studied properties of polymer and simple control, but present researches are studied a polymer actuator. An EP (Electostrictive Polymer) actuator has properties which change variably ils shape and environmental condition. Therefore, in order to coincide with a user's purpose, it is important not only to decide a shape of actuator and mechanical design but also to investigate a efficient controller. In this paper, we constructed the control logic with an adaptive fuzzy algorithm which depends on the physical properties of EP that has a dielectric constant depending on time. It caused for a sub-actuator to operate at the same time that a sub-actuator system operation increase with a functional improvement and control efficiency improvement in each actuator, hence it becomes very important to manage it effectively and to control the sub-system which Is operated effectively. There is a limitation on the management of Main-host system which has multiple sub-system, hence it brings out the Multi-Vehicle Control process that disperse the task efficiently. Controlling the multi-dispersion system efficiently, it needs the research of Main-host system's scheduling, data interchange between sub-actuators, data interchange between Main-host system and sub-actuator system, and data communication process. Therefore in this papers, we compared the fuzzy controller with the adaptive fuzzy controller. also, we applied the scheduling method for efficient multi-control in EP Actuator and the algorithm with interchanging data, protocol design.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1995년도 하계학술대회 논문집 B
• /
• pp.699-701
• /
• 1995

An input estimation technique is derived in multi-sensor environment. The proposed approach distribute the computational burden of input estimation to each local sensor and fusion center without loss of its optimality. The performances of proposed method in 2-sensor system are compared with those in single sensor system. Simulation results show that a reliable maneuvering target tracking system can be constructed in multi-sensor environment via proposed approach.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 1997년도 추계학술대회 논문집
• /
• pp.307-310
• /
• 1997

In case of environment requiring safety such as human body and requiring flexible shape, a conventional mechanical actuator system does not satisfy requirement. Therefore, in order to solve this problem, a research of various smart material such as EAP (Electro Active Polymer), EAC (Electro Active Ceramic) and SMA (Shape Memory Alloy) is in progress. Recently, the highest preferring material among various smart material is EP (Electrostictive Polymer), because it has very fast response time, poerful force and large displacement. The previous researches have been studied properties of polymer and simple control, but present researches are studied a polymer actuator. An EP (Electostrictive Polymer) actuator has properties which change variably as shape and environmental condition. Therefore, in order to coincide with a user's purpose, it is important not only to decide a shape of actuator and mechanical design but also to investigate a efficient controller. In this paper, we constructed the control logic with an adaptive fuvy algorithm which depends on the physical properties of EP that has a dielectric constant depending on time.

• Journal of Electrical Engineering and Technology
• /
• 제13권2호
• /
• pp.742-751
• /
• 2018

Electric vehicles (EV) are emerging as the future transportation vehicle reflecting their potential safe environmental advantages. Vehicle to Grid (V2G) system describes the hybrid system in which the EV can communicate with the utility grid and the energy flows with insignificant effect between the utility grid and the EV. The paper presents an optimal power control and energy management strategy for Plug-In Electric Vehicle (PEV) charging stations using Wind-PV-FC-Battery renewable energy sources. The energy management optimization is structured and solved using Multi-Objective Particle Swarm Optimization (MOPSO) to determine and distribute at each time step the charging power among all accessible vehicles. The Model-Based Predictive (MPC) control strategy is used to plan PEV charging energy to increase the utilization of the wind, the FC and solar energy, decrease power taken from the power grid, and fulfil the charging power requirement of all vehicles. Desired features for EV battery chargers such as the near unity power factor with negligible harmonics for the ac source, well-regulated charging current for the battery, maximum output power, high efficiency, and high reliability are fully confirmed by the proposed solution.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 16-17 Oct. 1987
• /
• pp.398-402
• /
• 1987

In the process industries control & organization consist of interconnections on different levels. The process controls that run these industries are a collection of well-defined functions in the form of standard modules interconnected by a communication network. Real-Time(throughput, response time), operator communication, flexibility, back-up and recovery needs have distribute organization of both system hardware and software. Multi-level systems are aften advocated for controlling complex systems, such as, electric, water, oil, gas plants. In practice, these systems encompass computers and person with their various communication requirements and limitations. Hence, Careful mutual adaptation of computer communications and organizational structure is necessary. This paper concentrates on these interactions between process control and organization on the basis of industrial case studies.

• 항공우주기술
• /
• 제5권2호
• /
• pp.240-247
• /
• 2006

틸트로터 항공기는 회전익모드, 천이모드, 고정익모드를 동시에 갖는 복합 형상 항공기 이다. 각 비행모드에서 최적의 상태로 비행하기위해서는 조종면 변위를 적절히 분배하고 조합하는 조종면의 혼합기설계가 요구된다. 회전익과 고정익을 전환할 수 있도록 설계돤 천이모드는 나셀각의 변경에 따른 추력선이 변경되고 이로 인해 천이모드에서 피치, 롤, 요축에 대해 불필요한 힘과 모멘트를 발생시킨다. 본 논문에서는 나셀의 틸팅각 변화에 따라 발생하는 힘과 모멘트를 다른 조종면을 통해 적절히 조절하여 일관된 항공기의 운동이 발생하도록 하는 스마트무인기 40% 축소모델에 대한 조종면 혼합기설계에 대해 서술하였다.

• 전기전자학회논문지
• /
• 제22권2호
• /
• pp.281-288
• /
• 2018

본 논문에서는 쿠다(CUDA)를 사용하여 GPU 리소스를 분배하는 지능형 얼굴 인식 및 트래킹 시스템을 제안한다. 제안한 시스템은 GPU 리소스를 최적의 상태로 분배하는 GPU 할당 알고리즘, 딥러닝을 이용한 얼굴 영역 검출, 딥러닝을 이용한 얼굴 인식, 실시간 얼굴 트래킹, PTZ 카메라 제어 등의 5단계로 구성되어진다. 멀티 GPU 리소스를 최적의 상태로 분배하는 GPU 할당 알고리즘은 고정적으로 스레드에 GPU를 할당하는 방식과 달리 GPU의 활성화 정도에 따라 유동적으로 GPU 리소스를 분배한다. 따라서 안정적이고 효율적인 멀티 GPU 사용을 가능하게 하는 특징이 있다. 제안된 시스템에 대한 성능을 평가하기 위하여 리소스 분배를 하지 않은 시스템과 제안한 시스템을 비교한 결과, 리소스를 분배하지 않은 시스템은 불안정한 동작을 보이는 반면에 제안한 시스템에서는 안정적으로 구동됨으로서 효율적인 리소스 사용을 보였다. 따라서 제안된 시스템의 효용성이 입증되었다.

• 한국통신학회논문지
• /
• 제18권12호
• /
• pp.1870-1883
• /
• 1993

본 논문에서는 ATM 방식으로 운용되는 사용자 네트워크를 구축하기 위해서 필수적인 주요 기능 그룹들-B-TE, B-NT2, LEX-이 수행하여야할 트래픽 제어기법에 대하여 연구한다. 사용자 네트워크에서 가장 중요한 기능 그룹인 B-NT2의 구성을 매우 단순화하여 정의한다. 또한 LEX의 구성기능 역시 B-NT2와 유사하게 정의한다. 가상 경로 식별자를 트래픽의 특성별로 고정할당하여 전체적인 트래픽 제어 기능의 분산을 가능하게 한다. 트래픽 제어를 위하여 연결수작 제어, 사용 파라미터 제어, 대역폭 할당 기능등의 연관성을 정의하고 소스 트래픽 특성에 따라 최적의 제어를 수행하기 위한 구조로서 멀티 룰-베이스 트래픽의 특성에 따른 최적의 제어를 수행하기 위한 구조로서 멀티 룰-베이스 구조를 제안한다. 그리고 멀티 룰-베이스 구조에 적합하도록 간단하게 구성된 실시간 가변 윈도우 알고리즘을 제안한다. 컴퓨터 시뮬레이션을 통하여 제안된 하드웨어적인 구성을 가지는 가상 시스템에 온 오프 소스 트래픽을 발생시켜서 제안한 알고리즘의 성능을 분석한다. 그리고 분산 제어의 기능성과 보다 단순화된 시스템의 구현이 가능함을 확인한다.

• International Journal of Aeronautical and Space Sciences
• /
• 제8권1호
• /
• pp.10-20
• /
• 2007

For spacecraft attitude control, reaction wheel (RW) steering laws with more than three wheels for three-axis attitude control can be derived by using a control allocation (CA) approach.1-2 The CA technique deals with a problem of distributing a given control demand to available sets of actuators.3-4 There are many references for CA with applications to aerospace systems. For spacecraft, the control torque command for three body-fixed reference frames can be constructed by a combination of multiple wheels, usually four-wheel pyramid sets. Multi-wheel configurations can be exploited to satisfy a body-axis control torque requirement while satisfying objectives such as minimum control energy.1-2 In general, the reaction wheel steering laws determine required torque command for each wheel in the form of matrix pseudo-inverse. In general, the attitude control command is generated in the form of a feedback control. The spacecraft body angular rate measured by gyros is used to estimate angular displacement also.⁵ Combination of the body angular rate and attitude parameters such as quaternion and MRPs(Modified Rodrigues Parameters) is typically used in synthesizing the control command which should be produced by RWs.¹ The attitude sensor signals are usually corrupted by noise; gyros tend to contain errors such as drift and random noise. The attitude determination system can estimate such errors, and provide best true signals for feedback control.⁶ Even if the attitude determination system, for instance, sophisticated algorithm such as the EKF(Extended Kalman Filter) algorithm⁶, can eliminate the errors efficiently, it is quite probable that the control command still contains noise sources. The noise and/or other high frequency components in the control command would cause the wheel speed to change in an undesirable manner. The closed-loop system, governed by the feedback control law, is also directly affected by the noise due to imperfect sensor characteristics. The noise components in the sensor signal should be mitigated so that the control command is isolated from the noise effect. This can be done by adding a filter to the sensor output or preventing rapid change in the control command. Dynamic control allocation(DCA), recently studied by Härkegård, is to distribute the control command in the sense of dynamics⁴: the allocation is made over a certain time interval, not a fixed time instant. The dynamic behavior of the control command is taken into account in the course of distributing the control command. Not only the control command requirement, but also variation of the control command over a sampling interval is included in the performance criterion to be optimized. The result is a control command in the form of a finite difference equation over the given time interval.⁴ It results in a filter dynamics by taking the previous control command into account for the synthesis of current control command. Stability of the proposed dynamic control allocation (CA) approach was proved to ensure the control command is bounded at the steady-state. In this study, we extended the results presented in Ref. 4 by adding a two-step dynamic CA term in deriving the control allocation law. Also, the strict equality constraint, between the virtual and actual control inputs, is relaxed in order to construct control command with a smooth profile. The proposed DCA technique is applied to a spacecraft attitude control problem. The sensor noise and/or irregular signals, which are existent in most of spacecraft attitude sensors, can be handled effectively by the proposed approach.