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Reduction of Dynamic False Contour Using Motion Estimation Method in PDP (움직임 예측을 통한 PDP 내에서의 의사 윤곽 제거 기법 연구)

  • 안상준;김창수;이상욱
    • Proceedings of the IEEK Conference
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    • 2003.11a
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    • pp.23-26
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    • 2003
  • In this work. we propose an algorithm for detecting and compensating dynamic false contours in plasma display panels (PDPs). First, we detect the candidate pixels, which are likely to be corrupted by false contours, and merge those pixels into several regions. Second, we estimate the motion vectors of the selected regions. Finally, based on the motion information. we modify the luminance values of the pixels in the regions to alleviate the effects of false contours. Simulation results demonstrate that the proposed algorithm efficiently reduces dynamic false contours at low computational complexity.

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Spectrum Sensing and Data Transmission in a Cognitive Relay Network Considering Spatial False Alarms

  • Tishita, Tasnina A.;Akhter, Sumiya;Islam, Md. Imdadul;Amin, M. Ruhul
    • Journal of Information Processing Systems
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    • v.10 no.3
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    • pp.459-470
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    • 2014
  • In this paper, the average probability of the symbol error rate (SER) and throughput are studied in the presence of joint spectrum sensing and data transmission in a cognitive relay network, which is in the environment of an optimal power allocation strategy. In this investigation, the main component in calculating the secondary throughput is the inclusion of the spatial false alarms, in addition to the conventional false alarms. It has been shown that there exists an optimal secondary power amplification factor at which the probability of SER has a minimum value, whereas the throughput has a maximum value. We performed a Monte-Carlo simulation to validate the analytical results.

Surgical Management of the Chronic Dissecting Aneurysm of Ascending Aorta with Aortic Regurgitation (만성 해리성 대동맥류 환자에서의 Bentall 씨 수술적응진성 및 가성 내강 동시 혈류공급술)

  • 강면식
    • Journal of Chest Surgery
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    • v.21 no.1
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    • pp.184-190
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    • 1988
  • The treatment of aortic aneurysm of ascending aorta has been fraught with difficult surgical problems. For the most part, these were resolved in 1968 with the introduction of a technique of total replacement of ascending aorta and reimplantation of the coronary arteries by Bentall and De Bono. This technique however, with all of its advantages, caries a certain problems. In chronic dissecting aneurysms, there is frequently a marked disparity in circumference between the true and false lumen distally. Distal perfusion is directed into both the true and false lumens by removing segment of the septum between the two lumens and constructing the distal graft anastomosis is to the outer layer of aortic adventitia. The distal false lumen, aortic branches and fenestrations have matured and healed in most cases. And importantly, major aortic tributaries may be solely dependent on the false lumen for perfusion. We are presenting two cases of chronic dissecting aneurysm of ascending aorta with aortic regurgitation, who have good result by surgical correction of so-called Bentall procedure with maintenance of blood flow directed into both true and false lumen.

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Physical Properties of Nylon Textured Yarn according to False Twist Texturing Parameters (I) - Effect of Speed and Draw Ratio - (가연조건에 따른 나일론 섬유의 물성 (I) - 가연속도와 연신비의 영향 -)

  • Hu, Jong-Tea
    • Textile Coloration and Finishing
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    • v.20 no.1
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    • pp.28-35
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    • 2008
  • Texturing is the process of including a characteristic of a natural fiber in a synthetic fiber. The most common method of it the false twist texturing. Nylon textured yarn is primarily manufactured by the disk type. The major process parameters or the disk type false twist machine ratio, disk/yarn, and heater temperature. This study therefore investigated the effects of false twist texturing, especially speed and draw ratio, on the physical properties of nylon textured yarn. The increase of speed was proportional to the increase of unwinding tension, which could reduce the production efficiency by elevating the tension affecting to fiber during the process. In addition, the increase of speed was inversely proportional to the increase of crimp rigidity of nylon textured yarn. Draw ratio was proportionally increased with the increase of tenacity and the reductions of fineness and elongation, showing the influence or draw ratio to the ultimate physical properties of textured yarn.

AUTOMATIC MOTION DETECTION USING FALSE BACKGROUND ELIMINATION

  • Seo, Jin Keun;Lee, Sukho
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.17 no.1
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    • pp.47-54
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    • 2013
  • This work deals with automatic motion detection for with surveillance tracking that aims to provide high-lighting movable objects which is discriminated from moving backgrounds such as moving trees, etc. For this aim, we perform a false background region detection together with an initial foreground detection. The false background detection detects the moving backgrounds, which become eliminated from the initial foreground detection. This false background detection is done by performing the bimodal segmentation on a deformed image, which is constructed using the information of the dominant colors in the background.

An Analysis of False Alarm Threshold Value by Heat Detector Using Heat Release Rate (열방출률을 이용한 열감지기의 오동작 경계값 분석)

  • 홍성호;김두현
    • Fire Science and Engineering
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    • v.17 no.3
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    • pp.26-30
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    • 2003
  • This paper presents a study on the analysis for false alarm of heat detector using HRR(Heat Release Rate). And it is represented to threshold value and domain of false alarm. The HRR threshold value of false alarm is calculated to use parameters obtained by small scale fire-experiment. The experiment is conducted to measure detector activation time and flame spread of wood cribs fire, etc. The results show that HRR threshold value of Fixed type detector is 20.24 kW and rate of rise type detector is 13.59 kW, respectively.

Analysis of the False Diffusion Effects in Numerical Simulation of Diesel Spray Impinging on Inclined Walls (경사진 벽충돌 디젤 분무에 대한 수치해석에서 오류확산이 미치는 영향)

  • Gwon, H.R.;Lee, S.H.
    • Journal of ILASS-Korea
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    • v.13 no.1
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    • pp.22-27
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    • 2008
  • The false diffusion occurs generally when the flow is oblique to the grid lines and when there is a non-zero gradient of the dependent variable in the direction normal to the flow. This numerical problem can overestimate diffusion terms in the continuous phase, causing the numerical inaccuracy for the simulation of impinging sprays on inclined walls because most of spray calculation uses rectangular grid system. Therefore, the main objective of this article is to investigate numerically the influence of false diffusion on numerical simulation for spray-wall impingement on inclined walls. It is found that unlike the spray impingement normal to the wall, the numerical diffusion exists in the case when diesel sprays impinge on the inclined walls with different angles. The results show that the correction function should be considered for accurate prediction of spray penetration length and more elaborate numerical schemes should be utilized to reduce the false diffusion.

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Structural Reliability Analysis of Automatic Fire Detectors for Reduction of False Alarms (화재감지기의 오보 감소를 위한 구조 신뢰도 분석)

  • 김주홍;임현교
    • Journal of the Korean Society of Safety
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    • v.8 no.1
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    • pp.6-12
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    • 1993
  • Now it is reported that there are many companies and factories which confront to the problem of false alarm in Automatic Fire Detecting System (AFDS). Though an AFDS is a high-priced and very important device in detecting a fire. the problem degrades the reliability and utility, eventually faith. of the system. This is a research concerned about the problem of false alarm of fire detectors in an AFDS. Structure of detectors was modeled up as a general K out-of n system. and reliability characteristics including false alarm rate and missed alarm rate, are derived from it. For decision of an optimal structure of detectors. preliminary analysis on various criteria is accomplished. It is concluded that appropriate modification of a detector with plural sensors may increase the system reliability and decrease the false alarm rate.

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Trust Based False-Positive Reduction Scheme against DoS Attacks (Trust 기반의 DoS 공격에 대한 False-Positive 감소 기법)

  • 박종경;이태근;강용혁;엄영익
    • Proceedings of the Korean Information Science Society Conference
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    • 2003.10a
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    • pp.697-699
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    • 2003
  • 최근의 네트워크 공격의 주류는 DoS (denial-of-service)와 DDoS (distributed DoS) 공격이다. 이러한 공격들은 공격자가 침입 대상 시스템의 자원을 완전히 소모시켜서 시스템이 정상적인 서비스를 할 수 없도록 하는 것이다. 각 시스템의 관리자들은 이러한 침입이나 공격을 막기 위한 방편 중에 하나로 IDS(Intrusion detection system)를 사용하고 있다. 그러나 IDS의 높은 false-positive(정상적인 사용을 공격으로 잘못 판단하는 경우)의 발생빈도는 심각한 문제점 중의 하나는 이다. 이런 false-positive의 발생빈도를 줄이고자 본 논문에서는 한번의 판단만으로 연결(connection)을 차단시키지 않고, trust라는 개념을 도입하여 trust의 값에 따라서 사용자에게 차등 서비스를 제공하는 기법을 제안한다. 즉, trust를 이용하는 기법은 각 사용자를 한번에 공격자인지 일반 사용자인지 결정하지 않고, 한 번 더 검사하여 false-positive의 발생빈도를 감소시키는 기법이다.

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Advanced Rule Pattern Generation Method for False Positive Reduction on Intrusion Detection System (침입탐지시스템에서 False Positive 감소를 위한 탐지규칙 패턴 생성 기법)

  • Lee, Suk-Won;Lee, Taek-Kyu;Choi, Myeong-Ryeol
    • Proceedings of the Korea Information Processing Society Conference
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    • 2015.04a
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    • pp.380-383
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    • 2015
  • 오용 탐지모델 기반의 침입탐지시스템은 새로운 사이버 공격을 탐지하기 위해 지속적으로 탐지규칙을 생성해야 한다. 공격에 대한 특징을 정확히 식별하지 못하고 탐지규칙을 생성할 경우 많은 false positive를 발생시키며, 이로 인해 침해사고 대응시간이 늦어진다. 본 논문에서는 침입탐지시스템에서 탐지된 이벤트의 true positive와 false positive 데이터를 Keyword Tree의 node에 경로를 지나가는 횟수를 누적하는 값을 포함시킨 자료구조를 기반으로 비교분석하여 false positive를 감소시킬 수 있는 탐지규칙 패턴 생성 기법을 제안한다.