• Journal of Korea Multimedia Society
• /
• v.5 no.3
• /
• pp.272-280
• /
• 2002

In this paper, we present a method to extract a moving object and to measure the distance to it by using the stereo vision system. The moving factor is to be extracted through a match of a pixel unit for the moving object where the adaptive threshold is effectively dealt with to remove changes in the brightness of the image. The distance to moving object is measured by using a stereo vision system which employs a parallel camera. The experimental results show that the proposed algorithm could be effectively applied to distance measurement to moving object because it has an average error of one percent.

• The Transactions of the Korean Institute of Electrical Engineers D
• /
• v.53 no.4
• /
• pp.258-264
• /
• 2004

This paper propose a method that GOP structure based on the picture complexity change realtime adaptive without pre-analysis or time delay. Proposed algorithm calculates the complexity of pictures at first, and the ratio of the complexity( X$\sub$p/ /X$\sub$i/) between P picture and I picture is calculated. The suitable M value for the three picture select by comparing with predetermined threshold. Used bit and vbv_delay the value of GOP is calculated according to selected M. Experimental results show that the prediction error is reduce than the fixed GOP structure. Since the complexity distribution of the sequence is different, applied limits of threshold value is changed, also.

• Proceedings of the IEEK Conference
• /
• 1998.06a
• /
• pp.835-838
• /
• 1998

본 연구에서는 칼라 CCD 센서를 제어하여, shading과 .gamma. correction 된 데이터를 읽어 들여, 이를 이진레벨 데이터로 바꾼후, 원래의 다치레벨 또는 이진레벨 데이터를 SCSI나 DMA I/F를 통해 전달하는 ASIC을 설계하였다. 본 ASIC에서는 이진화를 위하여 문자 모드에서는 simple threshold와 LAT(local adaptive threshold) 알고리즘을, 그림모드에서는 stucki error diffusion 알고리즘을 적용하였다. 그리고, 구성은 CCD센서 제어블락, 스텝 모타 제어제어블락, 이미지 축소블락, 데이터 이진화 블락, 그리고 DATA I/F 블락 등으로 이루어져 있다. 또한 사용된 technology는 삼성 0.5um CMOS standard cell이며, 크기는 45K gates(내부 메모리 제외)이고, 160QFP package로 구현되었다. ㅎㅁㅅㄷㄴ (soqn apa

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.11 no.3
• /
• pp.1393-1405
• /
• 2017

It is well known that duty-cycling control by dynamically adjusting the polling interval according to the traffic loads can effectively achieve power saving in wireless sensor networks. Thus, there has been a significant research effort in developing polling interval adaptation schemes. Especially, Dynamic Low Power Listening (DLPL) scheme is one of the most widely adopted open-looping polling interval adaptation techniques in wireless sensor networks. In DLPL scheme, if consecutive idle (busy) samplings reach a given fixed threshold, the polling interval is increased (decreased). However, due to the trial-and-error based approach, it may significantly deteriorate the system performance depending on given threshold parameters. In this paper, we propose a novel DLPL scheme, called SDL (Sequential hypothesis testing based Dynamic LPL), which employs sequential hypothesis testing to decide whether to change the polling interval conforming to various traffic conditions. Simulation results show that SDL achieves substantial power saving over state-of-the-art DLPL schemes.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.23 no.2
• /
• pp.166-171
• /
• 2013

The method proposed in this paper can improve the performance of the Boosting algorithm in machine learning. The proposed Boundary AdaBoost algorithm can make up for the weak points of Normal binary classifier using threshold boundary concepts. The new proposed boundary can be located near the threshold of the binary classifier. The proposed algorithm improves classification in areas where Normal binary classifier is weak. Thus, the optimal boundary final classifier can decrease error rates classified with more reasonable features. Finally, this paper derives the new algorithm's optimal solution, and it demonstrates how classifier accuracy can be improved using the proposed Boundary AdaBoost in a simulation experiment of pedestrian detection using 10-fold cross validation.

• Proceedings of the IEEK Conference
• /
• 2000.07b
• /
• pp.1041-1044
• /
• 2000

The enhancement to the back-propagation algorithm presented in this paper has resulted from the need to extract sparsely connected networks from networks employing product terms. The enhancement works in conjunction with the back-propagation weight update process, so that the actions of weight zeroing and weight stimulation enhance each other. It is shown that the error measure, can also be interpreted as rate of weight change (as opposed to ${\Delta}W_{ij}$), and consequently used to determine when weights have reached a stable state. Weights judged to be stable are then compared to a zero weight threshold. Should they fall below this threshold, then the weight in question is zeroed. Simulation of such a system is shown to return improved learning rates and reduce network connection requirements, with respect to the optimal network solution, trained using the normal back-propagation algorithm for Multi-Layer Perceptron (MLP), Higher Order Neural Network (HONN) and Sigma-Pi networks.

• The Transactions of the Korean Institute of Electrical Engineers P
• /
• v.51 no.1
• /
• pp.39-44
• /
• 2002

In this paper, implementation mode image segmentation method for separate image is presented. The method of segmentation image in conventional method, the error are generated by the threshold values. To improve these problem for segmentation image, the calculation of weighting factor using brightness distribution by histogram of stored images are proposed. For safe image of object and laser image, the computed weighting factor is set to the threshold value. Therefore the image erosion and spread are improved, the correct and reliable informations can be measured. In this paper, the system of 3-D extracting information using the proposed algorithm can be applied to manufactory automation, building automation, security guard system, and detecting information system for all of the industry areas.

• The Korean Journal of Applied Statistics
• /
• v.25 no.6
• /
• pp.1027-1036
• /
• 2012

Among various biometrics recognition systems, statistical fingerprint recognition matching methods are considered using minutiae on fingerprints. We define similarity distance measures based on the coordinate and angle of the minutiae, and suggest a fingerprint recognition model following statistical distributions. We could obtain confidence intervals of similarity distance for the same and different persons, and optimal thresholds to minimize two kinds of error rates for distance distributions. It is found that the two confidence intervals of the same and different persons are not overlapped and that the optimal threshold locates between two confidence intervals. Hence an alternative statistical matching method can be suggested by using nonoverlapped confidence intervals and optimal thresholds obtained from the distributions of similarity distances.

• Current Optics and Photonics
• /
• v.2 no.5
• /
• pp.431-435
• /
• 2018

A modified setup of a CMD technique for high power coherent beam combining was presented to address an issue of low damage threshold of electro-optic modulators. The feasibility of the modified setup was demonstrated by combining eight fiber beams, and it was successfully performed with ${\lambda}/44$ of residual phase error and 100 Hz of control bandwidth. It is expected that the modified CMD setup facilitates ultra-high power coherent beam combination without a limitation caused by the low damage threshold of electro-optic modulators.

• Journal of the Institute of Electronics Engineers of Korea SP
• /
• v.43 no.2 s.308
• /
• pp.40-47
• /
• 2006

This paper proposes a multitoning method using threshold modulation of MJBNM(Modified Jointly Blue Noise Mask) for banding artifacts reduction. As banding artifacts in multitoning appear as uniform dot distributions around the intermediate output levels, such multitone output results in discontinuity and visually unpleasing patterns in smooth transition regions. Therefore, to reduce these banding artifacts, the proposed method rearranges the dot distribution by introducing pixels in the neighborhood of output levels that occurs banding artifacts. First of all principal cause of banding artifacts are analyzed using mathematical description. Based on this analytical result, a threshold modulation technique of MJBNM which takes account of chrominance error and correlation between channels is applied. The original threshold range of MJBNM is first scaled linearly sot that the minimum and maximum of the scaled range include two pixel more than adjacent two output levels that cover an input value. In an input value is inside the vicinity of any intermediate output levels produce banding artifacts, the output is set to one of neighboring output levels based on the pointwise comparison result according to threshold modulation parameter that determines the dot density and distribution. In this case, adjacent pixels are introduced at the position where the scaled threshold values are located between two output levels and the minimum and maximum threshold values. Otherwise, a conventional multitoning method is applied. As a result, the proposed method effectively decreased the appearance of banding artifacts around the intermediate output levels. To evaluate the quality of the multitone result, HVS-WRMSE according to gray level for gray ramp image and S-CIELAB color difference for color ramp image are compared with other methods.