• The KIPS Transactions:PartA
• /
• v.16A no.4
• /
• pp.235-244
• /
• 2009

The mission-critical computer for air defense has to maintain its operation without any fault for a long mission time and is required to implement at low cost. Now the reliability of the mission critical-computer using Active Sparing Redundancy fault-tolerant technique is inferior to that of the computer using TMR technique. So in this paper are proposed Extended ASR(EASR) technique that provides higher reliability than that of the computer using TMR technique. The fault-tolerant performance of the implemented mission-critical computer is proven through reliability analysis and numbers of fault recovery test. Also, the reliability of the mission-critical computer using EASR technique is compared with those of computer using ASR and TMR techniques. EASR technique is very suitable to the mission-critical computer.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.24 no.6
• /
• pp.759-767
• /
• 2020

This paper proposes a new Recurrent neural network (RNN) based spectrum sensing technique for cognitive radio communications. The proposed technique determines the existence of primary user's signal without any prior information of the primary users. The method performs high-speed sampling by considering the whole sensing bandwidth and then converts the signal into frequency spectrum via fast Fourier transform (FFT). This spectrum signal is cut in sensing channel bandwidth and entered into the RNN to determine the channel vacancy. The performance of the proposed technique is verified through computer simulations. According to the results, the proposed one is superior to more than 2 [dB] than the existing threshold-based technique and has similar performance to that of the existing Convolutional neural network (CNN) based method. In addition, experiments are carried out in indoor environments and the results show that the proposed technique performs more than 4 [dB] better than both the conventional threshold-based and the CNN based methods.

• Journal of the Korea Society of Computer and Information
• /
• v.28 no.4
• /
• pp.113-120
• /
• 2023

Smart farms are steadily increasing in research to minimize labor, energy, and quantity put into crops as IoT technology and artificial intelligence technology are combined. However, research on efficiently managing crop growth information in smart farms has been insufficient to date. In this paper, we propose a management technique that can efficiently monitor crop growth information by applying autonomous sensors to smart farms. The proposed technique focuses on collecting crop growth information through autonomous sensors and then recycling the growth information to crop cultivation. In particular, the proposed technique allocates crop growth information to one slot and then weights each crop to perform load balancing, minimizing interference between crop growth information. In addition, when processing crop growth information in four stages (sensing detection stage, sensing transmission stage, application processing stage, data management stage, etc.), the proposed technique computerizes important crop management points in real time, so an immediate warning system works outside of the management criteria. As a result of the performance evaluation, the accuracy of the autonomous sensor was improved by 22.9% on average compared to the existing technique, and the efficiency was improved by 16.4% on average compared to the existing technique.

• Proceedings of the KIEE Conference
• /
• 1999.07d
• /
• pp.1980-1982
• /
• 1999

Conductive Langmuir-Blodgett(LB) films have recently attracted much interest from the viewpoint of ultrathin film conductors at the molecular level. The result shows that the Maxwell-displacement-current (MDC) measuring technique is useful in the detection of phase-transitions over the entire range of molecule areas. In this parer, electrical properties of PBDG Langmuir(L) films were investigated using a displacement current measuring technique with pressure stimulation. Displacement current was generated When the Spread volume $150{\mu}{\ell}$ and compression velocity was about 30, 40, 50 mm/min. In the result, it is known that current is generated of higher current peek as compression velocity become faster.

• IEIE Transactions on Smart Processing and Computing
• /
• v.5 no.3
• /
• pp.199-206
• /
• 2016

This paper describes a simple routing control system. We propose achieving high-speed data transmission without modifying the data frame configuration. To add a routing control signal, called the "labeling signal" in this paper, to the data frame, we use a frequency modulation technique on the transmitted frame. This means you need not change the data frame when you transmit additional signals. Using a prototype system comprising a field-programmable gate array and discrete elements, we investigate the system performance and devise a method to achieve high resolution. A three-channel routing control for a 10 Gb/s data frame was achieved, which confirms the advantages of the proposed system.

• Structural Monitoring and Maintenance
• /
• v.3 no.4
• /
• pp.395-406
• /
• 2016

Modal parameter identification has received much attention recently for their usefulness in earthquake engineering, damage detection and structural health monitoring. The identification method based on Matrix Pencil technique is adopted in this paper to identify structural modal parameters, such as natural frequencies, damping ratios and modal shapes using impulse vibration responses. This method can also be applied to dynamic responses induced by stationary and white-noise inputs since the auto- and cross-correlation function of the two outputs has the same form as the impulse response dynamic functions. Matrix Pencil method is very robust to noise contained in the measurement data. It has a lower variance of estimates of the parameters of interest than the Polynomial Method, and is also computationally more efficient. The numerical simulation results show that this technique can identify modal parameters accurately even if the noise level is high.

• Proceedings of the Korean Society of Computer Information Conference
• /
• 2016.07a
• /
• pp.93-94
• /
• 2016

사용자가 편리하게 사용하는 USB 인터페이스를 지원하는 컨트롤러 내부에 저장된 펌웨어를 조작하여 악의적인 행위를 수행하는 BAD USB가 출현하였다. BAD USB의 경우에는 악의적인 코드가 호스트에 존재하는 것이 아니라 장치 내부의 펌웨어에 존재하기 때문에 현재의 안티 바이러스 제품이 탐지하지 못하므로 그 대응방안이 시급하다. 이에 BAD USB를 탐지하고 대응하기 위한 연구가 활발히 진행되는 추세이지만, 아직 해결책으로는 미비한 실정이다. 따라서 본 논문에서는 사용자 인지를 기반으로 BAD USB를 탐지하는 방안을 제안한다.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.41 no.8
• /
• pp.911-913
• /
• 2016

Recently barcode detection using a camera is popular, but the recognition performance is low at the effectively low-resolution. The paper propose sub-pixel synchronization technique for better recognition performance. The experiments with ITF-18 demonstrates its performance gain (66% for CIF, 100% for VGA) against the existing recognition algorithms.

• The Transactions of the Korean Institute of Electrical Engineers
• /
• v.33 no.5
• /
• pp.173-180
• /
• 1984

The spectra of scattering light fromlaser-produced plasma near its fundamental and second harmonic wavelength were observed respectively by means of spectroscopic technique. The experimental results and the generation mechanism of nonlinear effects such as the second garmonics and the brillouin scattering were analysed theoretically. The spectra of reflected laser light became wider than that of incident laser light. And the peak of spectrum of reflected light shifted to red-side from that of incident light. The second harmonic light is generated from the nonlinear interaction of the incident laser light and the electron plasma wave excited in resonance region by the oblique incidence of laser light to the plasma. The Brillouin backscattering from laser-produced plasmas of hydrogen and deuterium has shown an isotope effect in the red-side region of the generated second harmonic light. This isotope shift is explained by the parametric instability at the cutoff (resonance) region using frequency-and phase-matching conditions of the waves.

• Proceedings of the IEEK Conference
• /
• 2001.09a
• /
• pp.231-234
• /
• 2001

In this paper, we present a robust watermarking technique based on a DCT-domain watermarking approach and an order statistic(OS) filter. The proposed technique inserts one watermark into each of four coefficients within a 2 ${\times}$ 2 block which is scanned on DCT coefficients in the zig-zag ordering from the medium frequency range. The detection algorithm uses an adaptive trimmed mean operator as a local estimator of the embedded watermark to obtain the desired robustness in the presence of additive Gaussian noise and JPEG compression attacks. The performance is analyzed through statistical analysis and numerical experiments. It is shown that the robustness properties against additive noise and JPEG compression attacks are more enhanced than the previous techniques.