• Journal of rehabilitation welfare engineering & assistive technology
• /
• v.7 no.2
• /
• pp.47-54
• /
• 2013

In this paper, we present an inertial sensor-based motion capturing system to measure and analyze whole body movements. This system implements a wireless AHRS(attitude heading reference system) we developed using a combination of rate gyroscope, accelerometer and magnetometer sensor signals. Several AHRS modules mounted on segments of the patient's body provide the quaternions representing the patient segments's orientation in space. We performed 3D motion capture using the quaternion data calculated. And a method is also proposed for calculating three-dimensional inter-segment joint angle which is an important bio-mechanical measure for a variety of applications related to rehabilitation. To evaluate the performance of our AHRS module, the Vicon motion capture system, which offers millimeter resolution of 3D spatial displacements and orientations, is used as a reference. The evaluation resulted in a RMSE of 2.56 degree. The results suggest that our system will provide an in-depth insight into the effectiveness, appropriate level of care, and feedback of the rehabilitation process by performing real-time limbs or gait analysis during the post-stroke recovery process.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.50 no.6
• /
• pp.287-293
• /
• 2013

Cochlear implant (CI) is an auditory prosthesis that delivers electrical stimulation via inserted electrodes into a cochlea. To evaluate CI performance, it is important to understand how auditory nerves are responded to electrical stimulations. In clinic, electrically evoked compound action potential (ECAP) is measured. In this study, we developed 3D finite element (FE) cochlear model to simulate ECAP in response to electrical stimulation. The model prododuced ECAP similar to that measured in animal experiments and clinics. This 3D FE cochlear model could be used in electrical stimulus method study to improve CI by analyzing neural responses to electrical stimulations.

• Journal of Biomedical Engineering Research
• /
• v.20 no.4
• /
• pp.495-502
• /
• 1999

We propose efficient speech signal processing algorithms and a system for cochlear implant in this paper. The outer and the middle car which perform amplifying, lowpass filtering and AGC, are modeled by an analog system, and the inner ear acting as a time-delayed multi filter and the transducer is implemented by the DSP circuit which enables real-time processing. Especially, the basilar membrane characteristic of the inner ear is modeled by a nonlinear filter bank, and then tonotopy and periodicity of the auditory system is satisfied by using a pitch-synchronous multi-spectra(PSMS) method. Moreover, most of the speech processing is performed by S/W so the system can be easily modified. And as our program is written in C-language, it can be easily transplanted to the system using other processors.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2009.05a
• /
• pp.88-92
• /
• 2009

Total pressure recovery ratio in intake is crucial factor to the operational characteristics of supersonic propulsion system because it does not compress inlet air mechanically by compressor, but does compress inlet air by ram compression. As the result of that the dynamic characteristic analysis of engine was performed before the controller was designed, it could be ascertained when the AoA of flight vehicle increases, the buzz margin decreases so that the shock wave produced outside intake in the specified area according to flight operation's characteristics. Therefore the PID control algorithm was designed to be controlled buzz margin that the characteristic of shock wave could meet the requirement of performance in intake. The PID controller was designed that the buzz margin value is being positive number using the control variables; fuel flow and nozzle throat area.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.15 no.5
• /
• pp.29-41
• /
• 2016

V2X environment is the most popular part of the C-ITS based on the high technologies. To evaluate V2X environment technologies, radio communication range and market penetration rate of V2X vehicle are used. This paper studies the V2X environment considering various traffic congestion level, radio communication range and market penetration rate of V2X vehicle using the microscopic simulation (VISSIM) based on proper parameters and algorithm. In conclusion, V2X environment can reduce the congestion in proper traffic volume. However, if traffic volume is almost near the capacity, even V2X environment can't relieve the road condition. Furthermore, increase of the radio communication range does not always mean the decrease of the congestion and even with the small market penetration rate, it can also have an impact on the V2X environment. This result will be the foundation for the V2X environment much better.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.26 no.3
• /
• pp.285-296
• /
• 2010

Robot-assisted illuminating equipment based on image-processing technology was developed and then its accuracy was measured. The current system was designed to detect facial appearance using a camera and to illuminate it using a robot-assisted system. It was composed of a motion control component, a light control component and an image-processing component. Images were captured with a camera and following their acquisition the images that showed motion change were extracted in accordance with the Adaboost algorithm. Following the detection experiment for the oral cavity of patients based on image-processing technology, a higher degree of the facial recognition was obtained from the frontal view and the light robot arm was stably controlled.

• The KIPS Transactions:PartB
• /
• v.13B no.5 s.108
• /
• pp.525-532
• /
• 2006

This paper proposes a new class of image restoration on the Ising modeled binary 'Takbon' image by the flexible line-fitting ICM(Iterated conditional modes) method. Basically 'Takbon' image need be divided into two extreme regions, information and background one due to its stroke combinations. The main idea is the line process, comparing with the conventional ICM approaches which were based on partially rectangular structured point process. For calculating geometrical mechanism, we have defined line-fitting functions at each current pixel array which form the set of linear lines with gradients and lengths. By applying the Bayes' decision to this set, the region of the current pixel is decided as one of the binary levels. In this case, their statistical reiteration for distinct tracking between intra and extra region offers a criterion to decide the attachment at each step. Finally simulations using the binary 'Takbon' image are provided to demonstrate the effectiveness of our new algorithm

• The Journal of the Korea institute of electronic communication sciences
• /
• v.17 no.4
• /
• pp.625-632
• /
• 2022

Gas turbine generators in load-following operation in the domestic power system play a major role in maintaining the rated frequency, but often have poor frequency control. Therefore, after examining the control characteristics of the governor, which is a gas turbine speed control device, and analyzing the failure types, countermeasures were suggested for each case. In addition, it was confirmed through the governor response test that the gas turbine helps in frequency recovery depending on the speed of fuel control, but also acts as a factor impeding stable operation, such as rapid fluctuations in combustion chamber temperature and combustion vibration. Therefore, in order to maintain stable power quality, there was a need for thorough facility management as well as research on the governor control method in which the traditional PID control method and the machine learning algorithm, a core field of the 4th industry, were fused.