• Journal of the Korea Computer Industry Society
• /
• v.8 no.3
• /
• pp.173-180
• /
• 2007

This paper describes the point-detector arrays system to processes the fields of signal and noise of the turbulent atmosphere. By using aboves, the maxmum output of direct-detection shows a little differences between experimental datas and theoretical datas. As a whole the experimental datas are agreed with the joint Gaussian theoretical curves and K-distribution curves.

• Proceedings of the KIEE Conference
• /
• 2001.07b
• /
• pp.1239-1241
• /
• 2001

This research addresses a new vehicle detecting scheme which uses MR(Megneto Resistive) sensor. A vehicle detector which includes two MR sensors for detecting car presence and speed, sensor voltage amplifiers, signal processor, microprocessor, RF data transceiver and a simple car moving simulator is constructed. From experimental results with the vehicle detector the proposed vehicle detecting scheme was verified.

• 한국정보디스플레이학회:학술대회논문집
• /
• 2000.01a
• /
• pp.13-14
• /
• 2000

21.6" a-Si:H TFT array for direct conversion X-ray detector with 2480 by 3072 pixel is successfully developed. To obtain good X-ray image quality, novel structure, storage on BCB structure, is proposed. The structure reduces the parasitic capacitance of data line, one of the main sources of signal noise. Also, the structure shows higher failure resistance against defects than that of the old design.

• Proceedings of the Optical Society of Korea Conference
• /
• 2003.07a
• /
• pp.98-99
• /
• 2003

PIN photodiode has been used in solid-state detector for x-ray detection as a photosensor of visible light from scintillator. Since the light from CWO is short wavelength having peak at 490nm, the light is absorbed within a very shallow layer near the surface of the photodiode before arriving at the depletion layer and does not contribute to the signal. In designing the PIN photodiode, it is important to make the p-layer as shallow as possible. (omitted)

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.21 no.1
• /
• pp.155-160
• /
• 1996

In this paper, we consider the discrete-time known signal detection problem under the presence of additive noise exhibiting weak dependence. We derive the locally optimum, memoryless, and one-memory detector test statistics under a seakly dependent noise model. The performance characteristics of the one-memory detector can achieve almost optimum performance at the expense of only one memory unit under the weakly dependent noise model.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
• /
• 2002.02a
• /
• pp.300-302
• /
• 2002

In this paper the high-speed fault current detector for superconducting fault current limiter is described. Detecting and interrupting the fault currents as quickly as possible is required in order not to exceed the thermal capacity of superconducting fault current limiter. A detecting method of an instantaneous fault current magnitude is adopted in the equipment described in this paper and a current signal through an analog/digital(A/D) converter would be compared with the reference in the digital signal processor(DSP). Around 20ms has elapsed for detecting the fault current. It is necessary to establish the appropriate trade-off between the reliability and detection speed.

• Journal of Sensor Science and Technology
• /
• v.21 no.6
• /
• pp.429-433
• /
• 2012

In this paper, we reduced the optical noise interference in a visible light communication system using two color LEDs. In the transmitter, the original and the inverted signals of the transmitted data modulated a red LED and a blue LED, respectively. In the receiver, a differential detector which is composed of two photodetectors and an optical red filter detected the mixed signal radiated from the two LEDs. In an environment that the optical noise from a fluorescent lamp exists, the signal-to-noise ratio in this system was improved by about 20dB compared to that in the conventional system which uses a single LED and a single photodetector.

• Journal of Korean Society of Transportation
• /
• v.14 no.3
• /
• pp.91-125
• /
• 1996

The purpose of this paper is comparatively to evaluate the confidence of Vehicle-Detector informations for various detectors in order to test to be possible the application of these to real time traffic signal control. The detectors which are tested for this study are Circle-Shaped Loop, Ultrasonic, Microwave and Image detector. The tested items for each detectors are traffic volume, degree of saturation for through and left turn movement, speed and queue length, etc. These items for each are tested at the field according to several situations, such as dry day, raining day, night and daytime. The result of these tests are performed comparative analysis and statistical examination in order to increase the confidence of the experiments.

• 제어로봇시스템학회:학술대회논문집
• /
• 1996.10b
• /
• pp.828-831
• /
• 1996

Radiation monitoring system is needed at nuclear power plant and nuclear facility. Manual survey techniques are commonly used, but they are time consuming and somewhat inaccurate. Automatic radiation surveys are very important because it provides significant savings in men-rem and wages. Unmanned, remote automatic radiation measurement system should be small and light-weighted in order to mount on robotic system. The system we have developed consists of detection parts, signal processing part, interface, and software part. Position information is provided by using of a collimator. The measurement process is achieved by the scanning of detector and image processing techniques are used to display radiation levels. We designed collimators, detectors, signal processing circuit, and constructed prototype system. The goal of this system is the mapping of camera image and radiation level distribution.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.21 no.5
• /
• pp.1172-1179
• /
• 1996

General adaptive noise canceller(ANC) suffers from the misadjustment of adaptive filter weights, because of the gradient-estimate noise at steady state. In this paper, an adaptive noise cancellation algorithm with speech detector which is distinguishing speech from silence and adaptation-transient region is proposed. The speech detector uses property of adaptive prediction-error filter which can filter the highly correlated speech. To detect speech region, estimation error which is the output of the adaptive filter is applied to the adaptive prediction-error filter. When speech signal apears at the input of the adaptive prediction-error filter. The ratio of input and output energy of adaptive prediction-error filter becomes relatively lower. The ratio becomes large when the white noise appears at the input. So the region of speech is detected by the ratio. Sign algorithm is applied at speech region to prevent the weights from perturbing by output speech of ANC. As results of computer simulation, the proposed algorithm improves segmental SNR and SNR up to about 4 dBand 11 dB, respectively.