• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2016.10a
• /
• pp.101-104
• /
• 2016

In this study, we propose an algorithm to simulate the function of the coupling structure and having two neurons to find out exactly recover the temporary or permanent position errors that can occur during operation in a digital circuit was separated by function, a 3x3 array. If any particular part in the combined cells are differentiated cells have a problem that function to other cells caused an error and perform the same function are subjected to a step of apoptosis by the surrounding cells. Designed as a function block in the function and the internal structure having a cell structure of this digital circuit proposes an algorithm.

• Proceedings of the KSR Conference
• /
• 2006.11b
• /
• pp.802-810
• /
• 2006

For a thorough train control, the precise train position detection is necessarily required. The widely used current way for train position detection is the one of using track circuits. The track circuit has a simple structure, and has a high level of reliability. However trains can be detected only on track circuits, which have to be installed on all ground sections, and much amount of cost for its installation and maintenance is needed. In addition, for the track circuit, only discontinuous position detection is possible because of the features of the closed circuit loop configuration. As the recent advances in telecommunication technologies and high-tech vehicle-based control equipments, for the train position detection, the method to detect positions directly from on trains is being studied. Vehicle-based position detection method is to estimate train positions, speed, timing data continuously, and to use them as the control information. In this paper, the features of GPS navigation and DR navigation are analyzed, and the navigation filters are designed by constructing vehicle-based train position detection method by combining GPS navigation and DR navigation for their complementary cooperation, and by using kalman filter. The position estimation performance of the proposed method is also confirmed by simulations.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.13 no.2
• /
• pp.88-95
• /
• 2008

This paper proposes a fast fault detection algorithm under open-circuit fault of a switch for a brushless DC(BLDC) motor drive system. This proposed method is configured without the additional devices for fault detection and identification. The fault detection and identification are achieved by a simple algorithm using the operating characteristic of the BLDC motor. After the fault identification, the drive system is reconfigured for continuous operation. This system is reconfigured by four-switch topology connecting a faulty leg to the middle point of DC-link bidirectional switches. This proposed method can also be embedded into existing BLDC motor drive systems as a subroutine without excessive computational effort. The feasibility of a the proposed fault detection algorithm is validated in simulation and experiment.

• The Journal of Korea Robotics Society
• /
• v.4 no.4
• /
• pp.320-326
• /
• 2009

This paper proposed a new magnetic field detection algorithm to detect metal pieces in food producing processes. This algorithm can detect mixed metal pieces by sensing magnetic field. Some metal pieces are passed through an over-current circuit to magnetize them. The magnetic field sensor can detect the change in the magnetic field on theconveyor belt caused by the flow of the metal pieces in the food product. However, such a method detects the output of signals that change their amplitude and phase according to the movement of the conveyor belt with the food product, in which the equilibrium of the positive signal that is created in the receiver coil loses its balance due to the magnetized material. This includes not only the signal elements resulting from the effect of the alternating magnetic fields of the mixed metals, but also the signal elements resulting from the effect of the alternating magnetic fields of the examined object itself.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2000.10a
• /
• pp.577-580
• /
• 2000

The aim of this paper is to develop a high stable measuring device for radioactive pulses. The device consists of a high voltage supply unit using a fly-back converter principle, and a pulse detection unit for gamma-rays and neutrons. The high voltage supply unit designed can generate DC voltage up to 1,500v at 5V-input, and have a series voltage regulator to maintain the output voltage constantly, resulting in less than 1.63% of voltage regulation. The pulse detection parts consists of an active integrator, a pole-zero circuit, and a 3-stage amplifier of 60 dB, and its frequency bandwidth is from 37 Hz to 300 kHz. From the experimental results, it is confirmed that the measuring device can count at least 10,000 pulses in a second.

• Proceedings of the KIPE Conference
• /
• 2004.07b
• /
• pp.660-664
• /
• 2004

The indirect rotor position detection method using terminal voltage of brushless DC motor (BLDCM) requires simple control circuit, and has wide speed range of sensorless operation. However, because the substantial phase difference exists between real back emf and terminal voltage, the existing indirect detection method using analog filter which is affected by frequency, speed, and load sensitively cannot be synchronized with current, in the end, it advances or delays. This paper presents new analog filter circuit design for rotor position estimation in order to solve the problem, and proposes novel sensorless operation method which is stable even in high speed range and not influenced by parameters with analysis on phase difference by load and speed. Moreover, the appropriateness of the proposed sensorless drive in this paper is verified and analyzed by experimentation.

• Proceedings of the IEEK Conference
• /
• 2003.07b
• /
• pp.1193-1196
• /
• 2003

This paper proposes a 2x oversampling method with a smart sampling for a clock and data recovery(CDR) circuit in a 2.5Gbps serial data link. In the conventional 2x oversampling method, the "bang-bang" operation of the phase detection produces a systematic jitter in CDR. The smart sampling in phase detection helps the CDR to remove the "bang-bang" operation and to improve the jitter performance. The CDR with the proposed 2x oversampling method is designed using Samsung 0.25${\mu}{\textrm}{m}$ process parameters and verified by simulation. Simulation result shows the proposed 2x oversampling method removes the systematic jitter.e systematic jitter.

• Journal of Institute of Control, Robotics and Systems
• /
• v.4 no.3
• /
• pp.406-412
• /
• 1998

This paper describes a contact position detection method of a capacitive touch screen panel. The proposed method is composed of a circuited compensating algorithm generating an output signal having phase difference to an input signal associated with contact position, converts both input and output signals into digital waveform (5V logic), and calculates the phase difference. Finally, position information with the phase difference is obtained by using a low-cost microprocessor, which is convenient to compensate non-linearity error. The proposed method, that computes phase difference directly, has advantages in feasibility and cost because it minimizes the use of analog devices; rather, it utilizes, cost effective digital circuit. Analytical results are also given.

• Journal of the Korean Society for Aviation and Aeronautics
• /
• v.27 no.3
• /
• pp.15-23
• /
• 2019

This paper contains analyses and development processes of the requirements to detect the possible intermittent failure in an old avionics backplane. Interconnections for signal transmission between electronic components, such as Pin-to-PCB, FPCB-to-FPCB, pin-to-FPCB, and pint-to-wire, were selected as the main cause of intermittent failure by analyzing target equipment and documents. The possibility of detecting intermittent failures occurring in the target equipment is verified by physics-of-failure analyses. In order to verify the occurrence of intermittent failures and their detectability, latching continuity circuit testers were manufactured and accelerated life tests were performed by applying temperature and vibration cycle in consideration of flight conditions. Through the above process, the detection requirements for the major intermittent failure in the target avionics backplane was developed.

• Journal of the Institute of Electronics and Information Engineers
• /
• v.50 no.8
• /
• pp.151-161
• /
• 2013

An active power factor correction (PFC) circuit is presented which employs a newly proposed input voltage sensor-less control technique operated in continuous conduction mode (CCM) and critical conduction mode (CRM). The conventional PFC circuit with input voltage sensor-less control technique degrades the power factor (PF) under the light load condition due to DCM operation. In the proposed PFC circuit, the switching frequency is basically 70KHz in CCM operation. In light load condition, however, the PFC circuit operates in CRM and the switching frequency is increased up to 200KHz. So CCM/CRM operation of the PFC circuit alleviates the decreasing of the PF in light load condition. The proposed PFC controller IC has been implemented in a $0.35{\mu}m$ BCDMOS process and a 240W PFC prototype is built. Experimental results shows the PF of the proposed PFC circuit is improved up to 10% from the one employing the conventional CCM/DCM dual mode control technique. Also, the PF is improved up to 4% in the light load condition of the IEC 61000-3-2 Class D specifications.