• Proceedings of the Korea Technology Innovation Society Conference
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• 2003.11a
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• pp.115-133
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• 2003

본 연구에서는 번호이동성 제도의 시차 도입이 이동통신시장에 미치는 영향과 동 제도와 관련된 경제적 후생효과를 추정하였다. 전문조사기관이 조사한 churn rate를 이용하여 2004년-2007년간 사업자별 시장점유율 추정결과는 2004년에는 선발사업자의 점유율은 낮아지고 후발사업자의 점유율은 높아져 유효경쟁체제를 구축하는 방향으로 움직이지만 churn in/out 효과가 모두 반영되는 2005년 이후 장기적으로는 정부의 정책목표가 달성되지 않을 수도 있음을 보이고 있다. 한편 번호이동성이 가져올 경제적 후생효과로는 동 제도를 일시 도입하는 경우 약 3,323억원의 후생이 발생하고, 6개월 시차 도입하는 경우에는 경쟁활성화 효과를 무시하면 이보다 7.85% 감소한 약 3,062억원으로 추정되었다. 또한 요금인하 수준이 분당 0.3원 정도 되면 시차 도입으로 인한 경쟁 효과가 시차제 적용으로 인한 후생 손실을 보전할 수 있는 것으로 나타났다.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2012.11a
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• pp.170-171
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• 2012

본 논문에서는 다시점 영상 부호화 시 효율적인 부호화를 위해 이웃한 시점 영상의 부호화 정보를 이용하는데 있어 영상 간의 최대 시차 정보를 이용하여 부호화 하는 방법을 제안한다. 다시점 비디오 부호화 방법은 일반적인 단일 시점 영상의 부호화와 같이 화면 내 참조, 화면 간 참조를 수행할 뿐만 아니라, 이웃한 시점의 영상을 참조하여 부호화 하는 시점 간 참조를 수행한다. 현재 표준화가 진행중인 HEVC 기반의 다시점 부호화 방법에서는, 시점 간 참조 시 이미 부호화가 완료된 이웃한 블록으로부터 시차 벡터 (Disparity vector)를 유도하여 부호화 하는 방법도 사용된다. 이 때 이웃한 블록들로부터 얻어낼 수 있는 시차 벡터가 여러 개일 때, 최대의 절대값을 갖는 시차 벡터를 선택함으로써 부호화 효율을 높일 수 있다.

• Journal of Broadcast Engineering
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• v.9 no.1
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• pp.91-94
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• 2004

The vergence controls of the parallel stereoscopic camera need only the disparity information of left and right images in horizontal direction. This paper proposed past and precise disparity value for stereoscopicimage pair in horizontal direction and the algorithm which can abstract disparity information through the HCF(Hybrid Cepstral Filter) for sign information. The proposed disparity information- extracting algorithm can obtain accurate disparity value of horizontal direction and signinformation by using both the one dimension cepstral filter which uses vertical projection data of left and right Image and the two dimension cepstral filter which uses down sampled image.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.10
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• pp.1829-1834
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• 2006

In this raper in order to recover sharp object boundaries we propose a new efficient stereo matching algorithm in which window size is varied to the distance from the boundaries of object. To this end, the processing region is divided into small subregions with a same area and the disparities of the center pixels in the subregions are calculated using a area-based algorithm with multiple windows. From the this disparity map we can find the edges of the contracted objects. The disparities of original image are obtained using the gradient constraint that means the disparity of the center pixel is similar to the ones of the remaining pixels in the subregion. from the experimental results it is found that the proposed algorithm is very good for recovering sharp object boundaries compared to the similar different algorithm.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.34 no.11B
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• pp.1320-1327
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• 2009

In stereoscopy using stereo camera system, the representative factors inducing stereoscopic depth distortions have been reported such as the inter camera distance, the convergence angle and the depth resolution. The image distance is just known to us as a factor related in optical system. In a point of view of depth distortion, it will be a factor inducing a stereoscopic depth distortion. In this paper, we focused on the proof of our opinion that the image distance is one of the weighted factors inducing depth distortion under orthostereoscopic condition.

• Journal of the Institute of Convergence Signal Processing
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• v.6 no.3
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• pp.112-119
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• 2005

In this paper, a model of neural circuit was proposed, which abstracts the depth information in two images gotten from right and left retinas. The proposed neural circuit corresponds to binocular stereo vision based on psychologic and physiological knowledge, and we examine a restoration method of three-dimensional surface. In case of drawing a disparity based on characteristics of images, we can not abstract the depth information correctly if resemblant characteristics are repeated on the boundary region of an object. A binocular disparity is decided in a model of neural circuit by abstraction, synthesis, and correction of a disparity. And we propose a method which restores three-dimensional shape by correcting a depth information, and also restores a three-dimensional surface by mapping a left input image on the restored three-dimensional shape. And we confirmed that the computation time for disparity abstraction can be greatly reduced through the simulation.

• Tunnel and Underground Space
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• v.20 no.2
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• pp.112-118
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• 2010

Before blasts that can have direct impacts on human bodies or structures, it is necessary to assess impacts of ground vibration. Therefore, frequency has been recognized as an important factor in order to assess impact on ground vibration and damages. There have been many studies on impacts of frequency. But, there have been no studies on relations between vibration and frequency according to delay time difference. In this study, we examined the relations between delay time difference and frequency according to each frequency with which reinforcement and destructive intervention repeat through delay time difference obtained using superposition modeling of single hole blasting waveform based on the theory of time difference developed by Langefors.

• Korean Security Journal
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• no.55
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• pp.31-55
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• 2018

The purpose of this study is to analyze the precedence analysis of traffic safety facilities installation for traffic accidents. The main results were as follows. First, the precedence of the number of traffic safety signs installation for the number of traffic accident is follows. The number of traffic safety signs[total number] (time precedent 1), the number of traffic safety signs[attention] (time precedent 7), the number of traffic safety signs[regulation] (time precedent 7), the number of traffic safety signs[indication] (time precedent 4) precede the number of traffic accidents as negative(-) relationship. Second, the number of traffic signal equipments[pedestrian lamp] (time precedent 2) precedes the number of traffic accidents as negative(-) relationship. Third, the precedence of the increase/decrease rate of traffic safety facilities installation for the increase/decrease rate of traffic accident is follows. The increase/decrease rate of traffic safety signs[total number] (time precedent 1), the increase/decrease rate of traffic safety signs[attention] (time precedent 1), the increase/decrease rate of traffic safety signs[indication] (time precedent 1), the increase/decrease rate of traffic safety signs[auxiliary] (time precedent 1) precede the increase/decrease rate of traffic accidents as negative(-) relationship. Fourth, the increase/decrease rate of traffic signal equipments[pedestrian lamp] (time precedent 0) accompanies the increase/decrease rate of traffic accidents as positive (+) relationship.

• Journal of Korean Ophthalmic Optics Society
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• v.16 no.3
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• pp.299-305
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• 2011

Purpose: In watching 3D stereoscopic display using the binocular disparity, effect of difference of the pupillary distance between the adults and children on the perception of depth were investigated. Methods: The average PD of children was determined from the PD measurements of children of the elementary school of 2nd and 3rd grade in Seoul. The location of crossing visual axes were derived from the relation of the binocular disparity and the PD for the adults and children. Results: The average PD of the children was measured to be 57.3 mm which was smaller than the average PD of the adults that was known to be about 65 mm. As the binocular disparity increases to the positive direction, the crossing location steeply moves farther behind the screen. On the other hand, when the binocular disparity increases to the negative direction, the crossing location gradually moves toward the viewer. For the same amount of the binocular disparity, the crossing locations were derived to be larger for the children than the adults due to the difference of the PD. Therefore, children will perceive larger depth than the adults. Conclusions: Small PD of the viewer causes the larger amount of the depth perception. In producing the stereoscopic images, the average PD of children as well as adults need to be considered.

• KIPS Transactions on Software and Data Engineering
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• v.11 no.1
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• pp.51-58
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• 2022

Drivable area detection, one of the main functions of advanced driver assistance systems, means detecting an area where a vehicle can safely drive. The drivable area detection is closely related to the safety of the driver and it requires high accuracy with real-time operation. To satisfy these conditions, V-disparity-based method is widely used to detect a drivable area by calculating the road disparity value in each row of an image. However, the V-disparity-based method can falsely detect a non-road area as a road when the disparity value is not accurate or the disparity value of the object is equal to the disparity value of the road. In a road environment including vegetation, such as a highway and a country road, the vegetation area may be falsely detected as the drivable area because the disparity characteristics of the vegetation are similar to those of the road. Therefore, this paper proposes a drivable area detection method and hardware architecture with a high accuracy in road environments including vegetation areas by reducing the number of false detections caused by V-disparity characteristic. When 289 images provided by KITTI road dataset are used to evaluate the road detection performance of the proposed method, it shows an accuracy of 90.12% and a recall of 97.96%. In addition, when the proposed hardware architecture is implemented on the FPGA platform, it uses 8925 slice registers and 7066 slice LUTs.