• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2015.05a
• /
• pp.367-370
• /
• 2015

This paper proposes an improve method of the detection performance of traffic lights for autonomous driving cars. Earlier detection methods used to adopt color thresholding, template matching and based learning maching methods, but its have some problems such as recognition rate decreasing, slow processing time. The proposed method uses both detection mask and morphological preprocessing. Firstly, input color images are converted to YCbCr image in order to strengthen its illumination, and horizontal edge components are extracted in the Y Channel. Secondly, the region of interest is detected according to morphological characteristics of the traffic lights. Finally, the traffic signal is detected based on color distributions. The proposed method showed that the detection rate and processing time improved rather than the conventional algorithm about some surrounding environments.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.26 no.9
• /
• pp.783-789
• /
• 2015

This paper presents a Doherty power amplifier(DPA) operating in the 2.6 GHz band for long term evolution(LTE) systems. In order to achieve high efficiency, second and third harmonic impedances are controlled using a compact output matching network. The DPA was implemented using a gallium nitride high electron mobility transistor(GaN-HEMT) that has many advantages, such as high power density and high efficiency. The implemented DPA was measured using an LTE downlink signal with a 10 MHz bandwidth and 6.5 dB PAPR. The implemented DPA exhibited a gain of 13.1 dB, a power-added efficiency(PAE) of 57.6 %, and an ACLR of -25.7 dBc at an average output power of 33.4 dBm.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.4
• /
• pp.1667-1674
• /
• 2012

Objective: To explore the differential protein expression profile in EC304 gastric cancer cells induced by alphastatin. Methods: Cultured EC304 cells in the exponential phase of growth were randomly divided into alphastatin and control groups. Total proteins were extracted and the two dimensional electrophoresis (2-DE) technique was applied to analyze differences in expression with ImageMaster 2D Platinum 5.0 software. Proteins were identified using the MASCOT database and selected differently expressed proteins were characterised by western blotting and immunofluorescence. Results: $1350{\pm}90$ protein spots were detected by the ImageMaster software in the 2-DE gel images from the control and alphastatin groups. The match rate was about 72-80% for the spectrum profiles, with 29 significantly different protein spots being identified, 10 upregulated, 16 downregulated, two new and one lost. The MASCOT search scores were 64-666 and the peptide matching numbers were 3-27 with sequence coverage of 8-62%. Twenty-three proteins were checked by mass spectrometry, including decrease in Nm23 and profilin-2 isoform b associated with the regulation of actin multimerisation induced by extracellular signals. Conclusion: The proteome in EC304 cells is dramatically altered by alphastatin, which appears to play an important role in modulating cellular activity and anti-angiogenesis by regulating protein expression and signal transduction pathways through Nm23 and profilin-2 isoform b, providing new research directions for anti-angiogenic therapy of gastric cancer.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.48 no.2
• /
• pp.109-115
• /
• 2011

As fingerprinting method, k-nearest neighbor(KNN) has been widely applied for indoor location in wireless location area networks(WLAN), but its performance is sensitive to number of neighbors k and positions of reference points(RPs). So artificial neural network(ANN) clustering algorithm is applied to improve KNN, which is the KNN/ANN hybrid algorithm presented in this paper. For any pattern matching based algorithm in WLAN environment, the characteristics of signal to noise ratio(SNR) to multiple access points(APs) are utilized to establish database in the training phase, and in the estimation phase, the actual two dimensional coordinates of mobile unit(MU) are estimated based on the comparison between the new recorded SNR and fingerprints stored in database. In the proposed algorithm, through KNN, k RPs are firstly chosen as the data samples of ANN based on SNR. Then, the k RPs are classified into different clusters through ANN based on SNR. Experimental results indicate that the proposed KNN/ANN hybrid algorithm generally outperforms KNN algorithm when the locations error is less than 2m.

• Proceedings of the KIEE Conference
• /
• 1996.07c
• /
• pp.1968-1970
• /
• 1996

We investigate a surface-micromachined polysilicon microgyroscope, whose resonant frequencies are electrostatically-tunable after fabrication. The microgyroscope with two oscillation nudes has been designed so that the resonant frequency in the sensing mode is higher than that in the actuating mode. The microgyroscope has been fabricated by a 4-mask surface-micrormachining process, including the deep RIE of a $6{\mu}m$-thick LPCVD polycrystalline silicon layer. The resonant frequency in the sensing mode has been lowered to that in actuating mode through the adjustment of an inter-plate bias voltage; thereby achieving a frequency matching at 5.8kHz under the bias voltage of 2V in a reduced pressure of 0.1torr. For an input angular rate of $50^{\circ}/sec$, an output signal of 20mV has been measured from the tuned microgyroscope under an AC drive voltage of 2V with a DC bias voltage of 3V.

• Journal of Korea Multimedia Society
• /
• v.21 no.9
• /
• pp.1076-1089
• /
• 2018

Respiration is the process of moving air into and out of the lung. Respiration changes the temperature in the chamber while exchanging energy. Especially the temperature of the face. Respiration monitoring using an infrared camera measures the temperature change caused by breathing. The conventional method assumes that motion is not considered and measures respiration. These assumptions can not accurately measure the respiration rate when breathing moves. In addition, the respiration rate measurement is performed by counting the number of peaks of the breathing waveform by displaying the position of the peak in a specific window, and there is a disadvantage that the breathing rate can not be measured accurately. In this paper, we use KLT tracking and block matching to calibrate limited weak movements during breathing and extract respiration waveform. In order to increase the accuracy of the respiration rate, the position of the peak used in the breath calculation is calculated by converting from a single point to a high resolution. Through this process, the respiration signal could be extracted even in weak motion, and the respiration rate could be measured robustly even in various time windows.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.27 no.1C
• /
• pp.69-77
• /
• 2002

Sine digital signal processing for motion pictures requires huge amount of data computation to store, manipulate and transmit, more effective data compression is necessary. Therefore, the ITU-T recommended H.26x as data compression standards for digital motion pictures. The data compression method that eliminates time redundancies by motion estimation using relationship between picture frames has been widely used. Most video conding systems employ block matching algorithm for the motion estimation and compensation, and the algorithm is based on the minimun value of cast functions. Therefore, fast search algorithm rather than full search algorithm is more effective in real time low data rates encodings such as H.26x. In this paper, motion estimation employing the Nearest-Neighbors algorithm is designed to reduce search time using FPGA, coded in VHDL, and simulated and verified using Xilink Foundation.

• Korean Journal of Optics and Photonics
• /
• v.22 no.5
• /
• pp.223-229
• /
• 2011

We present a low jitter frequency up-conversion detector based on quasi-phase matched sum frequency generation in a periodically poled $LiNbO_3$ waveguide for efficient single-photon detection at 1.5 ${\mu}m$ telecommunication wavelengths. The maximum detection efficiency and the noise count rate using the pump power of 300 mW and the pump wavelength of 974 nm are about 7% and 480 kHz, respectively. We also characterize the timing jitter of the frequency up-conversion detector by analyzing the time distribution of the detection outputs for photons generated through a picosecond pump pulsed spontaneous parametric downconversion. The minimum timing jitter was measured to be about 39.1 ps. Coincidence measurement with a narrow time window for pulsed up-conversion photons can eliminate the unwanted noise counts and maximize signal to noise ratio.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.48 no.12
• /
• pp.73-81
• /
• 2011

As high speed digital systems continue to use components with faster edge rate and clock speeds, transmission of the digital information, it can bring about many troubles. The increasing requirement for controlled impedance PCBs becomes both a critical success factor and a design challenge to implement a system. Especially, the noise sources in high frequency digital systems include the noise in power supply, ground and packaging, and they destroy the fidelity of signals. Therefore PCB design with impendence matching is needed to improve fidelity of signal in H/W. In this paper, we have developed an impedance control and analysis tool for multi-layer PCB design, and simulates the tracks controlled impedance with the test coupon. So, it can save the design time and support the economical PCB design.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.44 no.6
• /
• pp.16-23
• /
• 2007

Changeable biometrics has been developed as a solution to problem of enhancing security and privacy. The idea is to transform a biometric signal or feature into a new one for the purposes of enrollment and matching. In this paper, we propose a changeable biometric system that can be applied to appearance based face recognition system. In the first step when using feature extraction, ICA(Independent Component Analysis) coefficient vectors extracted from an input face image are replaced randomly using their mean and variation. The transformed vectors by replacement are scrambled randomly and a new transformed face coefficient vector (transformed template) is generated by combination of the two transformed vectors. When this transformed template is compromised, it is replaced with new random numbers and a new scrambling rule. Because e transformed template is generated by e addition of two vectors, e original ICA coefficients could not be easily recovered from the transformed coefficients.