• 한국군사과학기술학회지
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• 제11권1호
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• pp.66-74
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• 2008

This paper presents a new small target detection method using scale invariant feature. Detecting small targets whose sizes are varying is very important to automatic target detection. Scale invariant feature using the Laplacian scale-space can detect different sizes of targets robustly compared to the conventional spatial filtering methods with fixed kernel size. Additionally, scale-reflected adaptive thresholding can reduce many false alarms. Experimental results with real IR images show the robustness of the proposed target detection in real world.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2013년도 춘계학술대회
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• pp.886-888
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• 2013

에지는 물체의 크기, 방향, 위치 등의 정보를 포함한다. 이러한 에지를 검출하기 위한 기존의 에지검출 방법은 Sobel, Prewitt, Roberts, Laplacian 연산자 등을 이용한 방법이다. 기존의 방법은 에지를 검출하기 위하여 고정된 가중치 마스크를 이용하며 에지 검출 특성이 다소 미흡하다. 따라서 이와 같은 기존의 방법의 단점을 보완하기 위하여, 본 논문에서는 표준편차 및 임계값에 따른 가중치를 이용한 에지 검출 알고리즘을 제안하였다.

• 한국통신학회논문지
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• 제21권10호
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• pp.2552-2562
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• 1996

In this paper, we propose a segmentation algorithm that can reliably separate moving objects from noisy background in the image sequance received from a camera at the fixed position. The proposed algorithm consists of three processes:generation of the difference image between the input image and the reference image, multilevel quantization of the difference image, and multistagemerging in the quantized image. The quantization process requantizes the difference image based on the multiple threshold values determined bythe histogram analysis. The merging starts from the seed region which created by using the highest threshold value and ends when termination conditions are met. the proposed method has been tested with various real imge sequances containing intruders. The test results show that the proposed algorithm can detect moving objects like intruders very effectively in the noisy environment.

• 한국통신학회논문지
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• 제33권10A호
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• pp.949-955
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• 2008

본 논문에서는 기존의 에너지 검출기의 성능이 왜곡된 통신 환경에 취약하다는 점을 보완하기 위해 적응형 임계치를 적용한 에너지 검출기를 제안하고 필요한 매개 변수 값을 도출하여 성능을 비교 분석한다. 제안한 방식을 적용한 성능은 사용자의 이동 속도가 느린 채널 상창인 3 km/h와 오경보 확률이 $P_f=10^{-1}$ 인 경우 주로 성능의 이득을 보았다.

• 대한음성학회:학술대회논문집
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• 대한음성학회 2005년도 추계 학술대회 발표논문집
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• pp.55-58
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• 2005

Music Summarization is to extract there presentative section of a song such as chorus or motif. In previous work, the length of music summarization was fixed, and the threshold to determine the chorus section was so sensitive that the tuning was needed. Also, the rapid change of rhythm or variation of sound effects make the chorus extraction errors. We suggest the linear regression for extracting the changeable length and for minimizing the effects of threshold variation. The experimental result shows that proposed method outperforms conventional one.

• 대한전자공학회논문지
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• 제24권3호
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• pp.459-465
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• 1987

This paper describes the circuit and the layout of the shift register which can be used for a scanner of image sensor. P-well concentration and threshold voltage for proper iperation are calculated on the basso of the fixed process and the layout design. The calculation procedure of maximum operation frequency is also carried out. It is ascertained by SPICE simulation that the shift register produces the outputn pulse without threshold voltage loss up to 13MHz.

• International journal of advanced smart convergence
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• 제11권4호
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• pp.81-87
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• 2022

In this paper, we propose a watershed algorithm that applies a high-frequency enhancement filter to emphasize the boundary and a local adaptive threshold to search for minimum points. The previous method causes the problem of over-segmentation, and over- segmentation appears around the boundary of the object, creating an inaccurate boundary of the region. The proposed method applies a high-frequency enhancement filter that emphasizes the high-frequency region while preserving the low-frequency region, and performs a minimum point search to consider local characteristics. When merging regions, a fixed threshold is applied. As a result of the experiment, the proposed method reduced the number of segmented regions by about 58% while preserving the boundaries of the regions compared to when high frequency emphasis filters were not used.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2001년도 추계학술대회 학술발표 논문집
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• pp.109-112
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• 2001

영상분할에 있어서 최적의 임계치를 구하는 것은 영상을 구성하고 있는 픽셀들을 의미있는 집단으로 나누는 거와 같으며 이를 위하여 퍼지화 정도를 측정하여 최소의 퍼지화 정도를 갖는 임계치를 최적의 임계치로 설정한다. 일반적으로 소속도는 하나의 픽셀과 그 픽셀이 속한 영역의 관계로 표현될 수 있는데 소속도 계산을 위한 엔트로피로 샤논(Shannon)함수를 사용한다[1]. Liang-Kai Huang에 의하여 제안된 알고리즘은 그 수렴속도 면에 있어서 많은 문제점을 갖고 있다[2]. 본 논문에서는 이런 수렴속도를 좀더 개선하기 위하여 SPOI(Simplified Fixed Point Iteration)를 제안하고 여러 가지 실험영상을 사용하여 졔안된 논문의 우수성을 보이고자 한다. 실험결과 적절한 임계치를 구하면서도 기존의 논문보다 속도면에서 상당히 우수한 특성을 보이고 있다.

• Journal of Electrical Engineering and Technology
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• 제2권4호
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• pp.420-427
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• 2007

This paper highlights the comparison of a proposed methods named adaptive undervoltage load shedding based PTSI techniques for undervoltage load shedding and two previous methods named Fixed Shed Fixed Delay (FSFD) and Variable Shed Variable Delay (VSVD) for avoiding voltage collapse. There are three main area considerations in load shedding schemes as the amount of load to be shed, the timing of load shedding event, and the location where load shed is to be shed. The proposed method, named as adaptive UVLS based PTSI seem to be most appropriate among the uncoordinated schemes. From the simulation result can be shown the Adaptive UVLS based PTSI give faster response, accurate and very sensitive control for the UVLS control technique. This technique is effectively when calculating the amount to be shed. Therefore, it is possible to bring the voltage to the threshold value in one step. Thus, the adaptive load shedding can effectively reduce the computational time for control strategy.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1999년도 춘계학술대회 논문집
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• pp.307-314
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• 1999

The potential use of ranging sensors for reducing the occurrence of accidents in real environment is explored by many companies and laboratories. Most of the sensors under investigation utilize the FMCW(Frequency Modulated Continuous Wave) waveforms. The automotive environment presents to the FMCW radar sensor a multitude of moving and fixed targets and the sensor must detect and track only the targets which may pose a threat of collision or passengers accident. The sensor must function accurately in the presence of background echoes generated by moving and fixed targets, ground reflections, atmospheric noises, including rains, fog, and, snow and noise generated within the receiver. False detection of the desired target in this environment may issue false alarms. That may be dangerous to the passenger and the vehicle. A high false alarm rate is totally unacceptable. The false alarm mechanism consists of noise peaks, crossing the threshold and the undesired response of the system to off lane targets which are not potentially hazardous to the radar equipped vehicle. This paper presents an improve technique safety performance for driver-less operation using FMCW radar sensors.