• Title/Summary/Keyword: Detection Threshold

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Performance Analysis of Convolution coded 16 QAM signal with Optimum Threshold Detection in Rician Fading Environments (라이시안 페이딩 환경에서 최적 검파 기법을 사용한 길쌈 부호화된 16 QAM 신호의 성능 해석)

  • Jyun, Gyung-Bai;Joung, Souk-Yoon;Kim, Eon-Gon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.2
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    • pp.61-66
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    • 2005
  • In this paper, we analyzed the error rate Performance of Convolution coded 16 QAM signal with Optimum Threshold Detection in Rician Fading Enviroments. The performance of 16-QAM signal with CTD (conventional threshold detection) which employs convolution coding technique was analyzed and the performance improvement of convolution coded 16-QAM signal with OTD (optimum threshold detection) which is varied according to fading parameter 'K' and AWGN in Rician Fading channel was simulated. As a result of analysis, it was shown the effect of performance improvement to overcome the environment of mobile radio data communication channel.

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An Enhanced Step Detection Algorithm with Threshold Function under Low Sampling Rate (낮은 샘플링 주파수에서 임계 함수를 사용한 개선된 걸음 검출 알고리즘)

  • Kim, Boyeon;Chang, Yunseok
    • KIPS Transactions on Computer and Communication Systems
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    • v.4 no.2
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    • pp.57-64
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    • 2015
  • At the case of peak threshold algorithm, 3-axes data should sample step data over 20 Hz to get sufficient accuracy. But most of the digital sensors like 3-axes accelerometer have very low sampling rate caused by low data communication speed on limited SPI or $I^2C$ bandwidth of the low-cost MPU for ubiquitous devices. If the data transfer rate of the 3-axes accelerometer is getting slow, the sampling rate also slows down and it finally degrades the data accuracy. In this study, we proved there is a distinct functional relation between the sampling rate and threshold on the peak threshold step detection algorithm under the 20Hz frequency, and made a threshold function through the experiments. As a result of experiments, when we apply threshold value from the threshold function instead of fixed threshold value, the step detection error rate can be lessen about 1.2% or under. Therefore, we can suggest a peak threshold based new step detection algorithm with threshold function and it can enhance the accuracy of step detection and step count. This algorithm not only can be applied on a digital step counter design, but also can be adopted any other low-cost ubiquitous sensor devices subjected on low sampling rate.

Cut Detection with Dynamic Threshold (동적 임계값을 이용한 컷 검출)

  • 윤인구;김우생
    • Proceedings of the IEEK Conference
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    • 1998.10a
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    • pp.919-922
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    • 1998
  • A content-base search method is required for video which has an unformatted and huge size of data. The index techniue is necessary for the content-based search of the video data. The first step of the video indexing is a cut detection. We propose a dynamic threshold method which change a threshold value during the cut detection process. We demonstrate that the proposed method is more efficient than the existing methods.

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Optimal selection of detection threshold for tracking systems (추적 시스템을 위한 최적 검출 문턱값 선택)

  • 정영헌
    • Proceedings of the IEEK Conference
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    • 1999.11a
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    • pp.1155-1158
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    • 1999
  • In this paper, we consider the optimal control of detection threshold to minimize the conditional mean-square state estimation error for the probabilistic data association (PDA) filter. Earlier works on this problem involved the cumbersome graphical optimization algorithm or time-consuming numerical optimization algorithm. Using the numerical approximation of information reduction factor, we obtained the closed-form optimal detection threshold. This results are very useful for real-time implemenation.

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Edge Detection using Windows with Adaptive Threshold (적응형 한계치를 갖는 윈도우를 이용한 에지 검출)

  • 송의석;오하랑;김준형
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.32B no.11
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    • pp.1424-1433
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    • 1995
  • The edge detection process serves to simplify the analysis of images by drastically reducing the amount of data to be processed, while preserving useful structural informations about object boundaries. At first, this paper proposes an edge detection algorithm to reduce the amount of computation. The gradients of pixels are calculated by using first order differential equations on the pixels with even rows and even columns or odd rows and odd columns, and they are compared with a threshold to decide edges. As a result, the computational complexity is reduced to one third or one forth compared with the provious ones. To enhance the accuracy of edge detection, a method with the adaptive threshold for each pixel window which is calculated by using characteristic values is proposed. In this case, the performance can be improved since the threshold is calculated properly for each window according to the local characteristics of corresponding window.

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The Decision Method of A Threshold in Sequence-based Anomaly Detection Sensor (순서기반 비정상행위 탐지 센서의 임계치 결정 방법)

  • Kim, Yong-Min;Kim, Min-Su;Kim, Hong-Geun;No, Bong-Nam
    • The KIPS Transactions:PartC
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    • v.8C no.5
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    • pp.507-516
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    • 2001
  • In this paper, we implement sequence-based anomaly detection sensor using SOM and HMM, and analyze what is important information in system call and how a threshold is decided. The new filtering and reduction rules of SOM reduces the input size of HMM. This gives real-time processing to HMM-based anomaly detection sensor. Also, we introduced an anomaly count into the sensor. Due to lessened sensibility, a user easily understand easily the detection information and false-positive was decreased. And the active coordination of the threshold value makes the detection sensor adapt according to the system condition.

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Comparison of Tracking Performace for a Maneuvering Target under the Variation of Maneuver Detection Thresholds (기동 유무 판별 기준의 변화에 따른 기동표적의 추적 성능 비교)

  • Park, Je-Hong;Lee, Woo-Joo;Lim, Sang-Seok
    • Journal of Advanced Navigation Technology
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    • v.6 no.3
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    • pp.231-240
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    • 2002
  • For a long time target maneuvers in tracking problem have been a difficult task to handle. In order to solve this problems. there have been various tracking techniques. In the development of a tracking filter for a maneuvering target, maneuver detection threshold plays a key role. However, no study of filter performance the varying maneuver detection threshold has been carried out so far. Instead, the maneuver detection have been chosen empirically. In this paper, the effect of detection threshold selection on the performance of the tracking filters was considered and the relationships between maneuvers and the detection threshold have been analyzed by simulation.

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Anomaly Detection in Livestock Environmental Time Series Data Using LSTM Autoencoders: A Comparison of Performance Based on Threshold Settings (LSTM 오토인코더를 활용한 축산 환경 시계열 데이터의 이상치 탐지: 경계값 설정에 따른 성능 비교)

  • Se Yeon Chung;Sang Cheol Kim
    • Smart Media Journal
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    • v.13 no.4
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    • pp.48-56
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    • 2024
  • In the livestock industry, detecting environmental outliers and predicting data are crucial tasks. Outliers in livestock environment data, typically gathered through time-series methods, can signal rapid changes in the environment and potential unexpected epidemics. Prompt detection and response to these outliers are essential to minimize stress in livestock and reduce economic losses for farmers by early detection of epidemic conditions. This study employs two methods to experiment and compare performances in setting thresholds that define outliers in livestock environment data outlier detection. The first method is an outlier detection using Mean Squared Error (MSE), and the second is an outlier detection using a Dynamic Threshold, which analyzes variability against the average value of previous data to identify outliers. The MSE-based method demonstrated a 94.98% accuracy rate, while the Dynamic Threshold method, which uses standard deviation, showed superior performance with 99.66% accuracy.

Skin Segmentation Using YUV and RGB Color Spaces

  • Al-Tairi, Zaher Hamid;Rahmat, Rahmita Wirza;Saripan, M. Iqbal;Sulaiman, Puteri Suhaiza
    • Journal of Information Processing Systems
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    • v.10 no.2
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    • pp.283-299
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    • 2014
  • Skin detection is used in many applications, such as face recognition, hand tracking, and human-computer interaction. There are many skin color detection algorithms that are used to extract human skin color regions that are based on the thresholding technique since it is simple and fast for computation. The efficiency of each color space depends on its robustness to the change in lighting and the ability to distinguish skin color pixels in images that have a complex background. For more accurate skin detection, we are proposing a new threshold based on RGB and YUV color spaces. The proposed approach starts by converting the RGB color space to the YUV color model. Then it separates the Y channel, which represents the intensity of the color model from the U and V channels to eliminate the effects of luminance. After that the threshold values are selected based on the testing of the boundary of skin colors with the help of the color histogram. Finally, the threshold was applied to the input image to extract skin parts. The detected skin regions were quantitatively compared to the actual skin parts in the input images to measure the accuracy and to compare the results of our threshold to the results of other's thresholds to prove the efficiency of our approach. The results of the experiment show that the proposed threshold is more robust in terms of dealing with the complex background and light conditions than others.

Accuracy Improvement Methode of Step Count Detection Using Variable Amplitude Threshold (가변 진폭 임계값을 이용한 걸음수 검출 정확도 향상 기법)

  • Ryu, Uk Jae;Kim, En Tae;An, Kyung Ho;Chang, Yun Seok
    • KIPS Transactions on Computer and Communication Systems
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    • v.2 no.6
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    • pp.257-264
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    • 2013
  • In this study, we have designed the variable amplitude threshold algorithm that can enhance the accuracy of step count using variable amplitude. This algorithm converts the x, y, z sensor values into a single energy value($E_t$) by using SVM(Signal Vector Magnitude) algorithm and can pick step count out over 99% of accuracy through the peak data detection algorithm and fixed peak threshold. To prove the results, We made the noise filtering with the fixed amplitude threshold from the amplitude of energy value that found out the detection error was increasing, and it's the key idea of the variable amplitude threshold that can be adapted on the continuous data evaluation. The experiment results shows that the variable amplitude threshold algorithm can improve the average step count accuracy up to 98.9% at 10 Hz sampling rate and 99.6% at 20Hz sampling rate.