• Journal of Digital Convergence
• /
• v.9 no.2
• /
• pp.53-63
• /
• 2011

In connection with each other through social networks, individuals share valuable knowledge and information. Furthermore the knowledge and information based on the collective intelligence is growing. Collective intelligence with more peoples will grow by gathering intelligence to enhance the collective intelligence. This study investigates the collective intelligence using business management game, and observes forming process of collective intelligence. To achieve the objective to observe the forming process of collective intelligence, only the test subjects available were exposed to the Corporate Management Game with SNS space. During the experimentation, the interaction and feedback were observed. The results of the study show that different performance, feedback and interaction for each group.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.12 no.5
• /
• pp.887-892
• /
• 2008

This paper is on a new adaptive algorithm which can cancel the acoustic feedback signals in the digital hearing aids. The proposed algorithm uses the normalized LMS algorithm with decorrelators. By doing so, it can be reduced the autocorrelation for the voice signals. To analyze the convergence characteristics of the proposed algorithm, the simulations were carried out about various input signals. And we had compared the performances of convergence for this algorithm with the ones for the NLMS algorithm. As the results of simulations, it is proved that the feedback canceller adopting this algorithm shows about 5-10 dB more high SNR than the NLMS algorithm for the colored inputs.

• Electronics and Telecommunications Trends
• /
• v.36 no.1
• /
• pp.99-108
• /
• 2021

Digital twins are digital replicas of objects and systems in the real world. These digital replicas in a virtual environment can be connected with smart sensors and a variety of analyses, and simulations of real-time data from these sensors enable effective the operation, rapid feedback, and future predictions of real world phenomena. Until now, digital twins have been adopted and used mainly in the field of manufacturing, especially for smart factories. As digital twins are expected to be useful not only for productivity improvement but also for social problem solving, it is predicted that they will be extended to other fields such as those of transportation and cities. Digital twins will especially help realize smart cities through real-time monitoring, operation, and predictions using virtual digital twin cities. This paper summarizes the trends in digital twins for smart cities, the concept of digital twins, their application to smart cities, the strategies of various countries, and the development status of companies.

• Therapeutic Science for Rehabilitation
• /
• v.11 no.4
• /
• pp.85-97
• /
• 2022

Purpose : This study aimed to investigate the effects of a digital pegboard training program with visual and auditory feedback on hand function and visual perception in stroke patients. Methods : Twenty two participants were randomly assigned to an experimental or control group. The experimental group received training using a digital pegboard training program with visual and auditory feedback (n=11), while traditional occupational therapy was administered to the control group (n=11). Hand function was assessed before and after the intervention using the Nine-Hole Peg Test and manual function test (MFT), while visual perception was assessed using the Motor-Free Visual Perception Test-3rd edition (MVPT-3). Results : Following the intervention, both the experimental and control groups showed significant improvements in performance in the Nine-Hole Peg Test and MVPT-3 (p<.05). The improvement on both tests was significantly greater in the experimental group than in the control group (p<.05). Conclusion : The results suggest that digital pegboard training with visual and auditory feedback may improve hand function and visual perception in stroke patients. Therefore, this intervention can be effective in occupational therapy to aid the recovery of stroke patients.

• 제어로봇시스템학회:학술대회논문집
• /
• 1991.10b
• /
• pp.1671-1676
• /
• 1991

Direct digital design of computed torque controllers for a robot manipulator is discussed in this paper. A simple discrete-time model of the robot manipulator obtained by Euler's method is used for the design. Taking account of computation delay in the digital processor, we propose predictor-based designs of the PD and PID type controllers. The PID type controller is designed based on a modified version of the discrete-time integral controller proposed by Mita. For both controllers, the same formulas can be used to determine the feedback gains. A simulation example is presented to compare the robustness of the proposed controllers against physical parameter variations.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 2004.10a
• /
• pp.443-446
• /
• 2004

This paper discusses an intelligent digital redesign technique for designing a fuzzy pulse-width-modulated (PWM) control. First when we are given a well-designed fuzzy analog control, the equivalent digital control is intelligently redesigned. Using the similar technique we intelligently redesign the fuzzy PWM control from the intelligently redesigned fuzzy digital control. A stabilizability of the intelligently redesigned PWM control is rigorously analyzed.

• 전기의세계
• /
• v.30 no.8
• /
• pp.509-516
• /
• 1981

The optimal control theory is applied to the design of a digital control system for a nuclear reactor. A linear dynamic model obtained at 85% of rated power and a quadratic performance index are used. A minimal order observer used in cascade with the feedback controller is suggested as a state estimator. The total reactor power control is studied in the range of 80% to 100% of rated power, with the steady state and load-following control. The control algorithm considered is suitable for implementation in direct digital control.

• 전기의세계
• /
• v.26 no.3
• /
• pp.63-68
• /
• 1977

In this paper, the theory of pulse frequency modulated DC/DC power converter to obtain constant output voltage for all input voltage changes is discussed. The switch controller consisting of integrator and comparator determines the ON time of power switch-Thyristor-by the error between the load voltage and a load reference voltage. Resulting voltage and current waveforms have been studied theoretically in detail and verified experimentally for a resistive and inductive load condition. State equations for voltages and currents using binary logic variables are computed by digital computer. Comparison of these withe oscillograms obtained from an experimental model shows very close agreement.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.05a
• /
• pp.109-109
• /
• 2004

구조물에 있어서 진동은 소음을 유발하며 구조물을 불안정하게 만드는 요인이 된다. 특히, 저주파 진동은 구조물에 미치는 영향이 크므로, 유연구조물의 저주파 진동모드들을 우선적으로 제어할 필요가 있다. 본 논문에서는 압전세라믹을 작동기로, 압전필름을 감지기로 사용하였고, 능동 제어 알고리즘의 하나인 적응형 디지털 PPF(Positive Position Feedback) 제어기를 구성하여 유연 외팔 평판과 열린 박스 구조물에서 저주파 진동을 감소시켰다.(중략)

• Journal of Electrical Engineering and information Science
• /
• v.2 no.3
• /
• pp.66-70
• /
• 1997

The steam generator level is susceptible to the nonminimum phase in dynamics due to the thermal reverse effects known as "shrink and swell" in a pressurized water reactor. A state feedback assisted control concept is presented for the change of dynamic performance to the minimum phase the concept incorporates a nonlinear digital observer as a part of the control system. The observer is deviced to estimate the state variables that provide the true indication of water inventory by compensating for shrink and swell effects. The concept is validated with implementation into the steam generator simulation model.