• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2000년도 ITC-CSCC -2
• /
• pp.1013-1016
• /
• 2000

In this study, the estimate speed of rotor in the induction motor with Model Reference Adaptive control System (MARC) principle and to study that vector control system feedbacks speed estimated to speed control system and its result is as follows; Considering with explanation an influence of speed estimation mechanism depend on error about the second resistance size established, it estimates the deviation of the second resistance establishment and exhibits a compensation method, what is more, it designs a reparation program using the fuzzy algorithm and testifies the result with the computer simulation. And besides, it composes the load torque estimation and estimates the load torque, as the result, feedback-compensating the result of estimation, it improves the efficiency. In consequence, it makes a good result for more powerful vector control system about the outside trouble.

• 한국동물학회지
• /
• 제30권4호
• /
• pp.432-444
• /
• 1987

Very early stage of chick embryo cultivated in the medium containing DLtryptophan by beaker method has been investigated in vitro morphologically using electron microscopy at cellular level and found that the development of tryptophan treated chick embryos corresponding to 18∼66 hrs incubation was impaired and york granule degradation was significantly delayed. It was also found that DNA, RNA and protein biosynthesis of tryptophan treated chick embryo was greatly lowered than those of control group. Conversion of L-tryptophan into serotonin was traced using 14C-L-tryptophan and found that 13.8cA of added radioactivity was recovered from serotonin formed during 18 hrs incubation and the amounts of serotonin formed were depend upon added amount of tryptophan in e99 yolk. It seemed that the serotonin formed from external tryptophan might inhibit the degradation of yolk granule by feedback mechanism, resulting in malformation of chick embryogenesis.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1983년도 하계학술회의강연.논문초록집
• /
• pp.135-138
• /
• 1983

This paper studies a variable structure adaptive model following control system which can control a plant in which the parameters of the controlled plant can not be estimated because they vary with time and in which the controlled plant has noise. The values of the feedback gain matrices for given states are obtained the equivalent control law, and the adaptive controller has been designed using the adaptive mechanism which switches the matrices. The adaptive controller minimizes the state error vector, that is, the difference between the state vector of the model and the state vector of the controlled plant. A controlled plant which has time varying parameters, a controlled plant which has only noise, and a controlled plant which has both have been controlled by the designed adaptive controller. The continuous single input-output system has been analysed by computer. This control system may be used to control practical systems by the addition of a microcomputer.

• Journal of Communications and Networks
• /
• 제18권2호
• /
• pp.246-260
• /
• 2016

A major challenge achieving scalable access control for a large number of subscribers in a public broadcast is to distribute key update messages reliably to all stateless receivers. However, in a public broadcast, the rekeying messages can be dropped or compromised during transmission over an insecure broadcast channel, or transmitted to receivers while they were off-line. In this study, we propose a novel group key management scheme. It features a mechanism to allow legitimate receivers to recover the current group key, even if they lose key update messages for long-term sessions. The scheme uses short hint messages and member computation. Performance analysis shows that the proposed scheme has the advantages of scalability and efficient rekeying compared to previous reliable group key distribution schemes. The proposed key management scheme targets a conditional access system in a media broadcast in which there is no feedback channel from receivers to the broadcasting station.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 심포지엄 논문집 정보 및 제어부문
• /
• pp.71-73
• /
• 2004

Recently many peoples served multimedia data from Internet. But characteristic of multimedia-object about that effect on weight and transport-time causes Streaming Application is restricted to high-quality-service. This research propose the Quality-of-service(QoS) supporting for Home Gateway that behaving Routing and media platform equipment, using CBQ Scheduling scheme. The QoS Supporting for Multimeda Service that using general Rouging policy is difficult because media platform locate in Home Gateway. Therefore this research propose Routing mechanism to QoS support of media platform located in Gateway using TCP based CBQ Control.

• 동력기계공학회지
• /
• 제6권1호
• /
• pp.96-101
• /
• 2002

In this paper, we address the problem of controlling an end-effector to track and grab a moving target using the visual servoing technique. A visual servo mechanism based on the image-based servoing principle, is proposed by using visual feedback to control an end-effector without calibrated robot and camera models. Firstly, we consider the control problem as a nonlinear least squares optimization and update the joint angles through the Taylor Series Expansion. And to track a moving target in real time, the Jacobian estimation scheme(Dynamic Broyden's Method) is used to estimate the combined robot and image Jacobian. Using this algorithm, we can drive the objective function value to a neighborhood of zero. To show the effectiveness of the proposed algorithm, simulation results for a six degree of freedom robot are presented.

• ETRI Journal
• /
• 제41권3호
• /
• pp.383-395
• /
• 2019

Clock Controlled Dual keeper Domino logic structures (CCDD_1 and CCDD_2) for achieving a high-speed performance with low power consumption and a good noise margin are proposed in this paper. The keeper control circuit comprises an additional PMOS keeper transistor controlled by the clock and foot node voltage. This control mechanism offers abrupt conditional control of the keeper circuit and reduces the contention current, leading to high-speed performance. The keeper transistor arrangement also reduces the loop gain associated with the feedback circuitry. Hence, the circuits offer less delay variability. The design and simulation of various wide fan-in designs using 180 nm CMOS technology validates the proposed CCDD_1 and CCDD_2 designs, offering an increased speed performance of 7.2% and 8.5%, respectively, over a conventional domino logic structure. The noise gain margin analysis proves good robustness of the CCDD structures when compared with a conventional domino logic circuit configuration. A Monte Carlo simulation for 2,000 runs under statistical process variations demonstrates that the proposed CCDD circuits offer a significantly reduced delay variability factor.

• 반도체디스플레이기술학회지
• /
• 제20권3호
• /
• pp.131-135
• /
• 2021

Numbers of studies related to optimization of design of organic light emitting diodes(OLED) through machine learning are increasing. We propose the generative method of the image to assess the performance of the device combining with machine learning technique. Principle parameter regarding dark spot growth mechanism of the OLED can be the key factor to determine the long-time performance. Captured images from actual device and randomly generated images at specific time and initial pinhole state are fed into the deep neural network system. The simulation reinforced by the machine learning technique can predict the device parameters accurately and faster. Similarly, the inverse design using multiple layer perceptron(MLP) system can infer the initial degradation factors at manufacturing with given device parameter to feedback the design of manufacturing process.

• 한국정밀공학회지
• /
• 제11권2호
• /
• pp.65-74
• /
• 1994

Backcap is an electric remote control system for the operation of directional flow control valves. This paper presents a new type of basckcap system which is characterized by its simple construction. The backcap is essentially a hydraulic cylinder of which the piston is connected to a spool of hydraulic valve and controlled by input current. An inherent feedback is imposed on its mechanism so that no artificial noe is needed. Characteristics of the backcap is verified by stability analysis, transient motion and steady state positioning for step inputs. Design parameter analyses have been executer by some analytical approaches and computer simulations, which lead to their optimal valves. These results contributed to an effective new backcap system and its design strategy.

• 국제학술발표논문집
• /
• The 6th International Conference on Construction Engineering and Project Management
• /
• pp.232-235
• /
• 2015

Defect data contains experiential knowledge about specific work conditions. And the number of projects performed by a company is too limited for an individual to experience the various defects under the current complex construction environment. Therefore, in order to manage and prevent a reoccurrence of defects, a proper data feedback mechanism is required. However, most defect data are stored in unstructured ways, resulting in the fundamental problem of data utilization. In this paper, a new framework is proposed by using linked data technologies to improve defect data utilization. The target of this framework is to convert defect data to the ontology-based linked data format for sharing defect data from different data sources. To demonstrate it, some technical solutions are implemented by using real cases. The proposed approach can reduce data search time and improve the accuracy of search results as well. Moreover, the proposed approach can be applied to other domains that need to refer to external sources such as safety, specification, product, and regulation.