• Title/Summary/Keyword: 최고 효율점

Search Result 319, Processing Time 0.036 seconds

Multi-view Video Coding with View Scalability (시점 계위성을 고려한 다시점 비디오 부호화 기법)

  • Kim, Jae-Sub;Choi, Mi-Nam;Baek, Yun-Ki;Kim, Dong-Wook;Kim, Hwa-Sung;Yoo, Ji-Sang
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.32 no.8C
    • /
    • pp.703-711
    • /
    • 2007
  • In this paper, we propose a multi-view coding(MVC) algorithm with considering view scalability. The proposed algorithm has a high compression efficiency by reducing inter-view redundancy through inter-view decomposition, and adaptively reconstructs a multi-view video from an encoded bit stream. Furthermore, a reference view can be decoded by a traditional H.264/AVC, and the other views are adaptively decoded at the receiver by filtering to support view scalability. Experimental results show that the proposed algorithm performed better than the conventional H.264 codec even though it offers the view scalability.

A Multiple Vehicle Object Detection Algorithm Using Feature Point Matching (특징점 매칭을 이용한 다중 차량 객체 검출 알고리즘)

  • Lee, Kyung-Min;Lin, Chi-Ho
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.17 no.1
    • /
    • pp.123-128
    • /
    • 2018
  • In this paper, we propose a multi-vehicle object detection algorithm using feature point matching that tracks efficient vehicle objects. The proposed algorithm extracts the feature points of the vehicle using the FAST algorithm for efficient vehicle object tracking. And True if the feature points are included in the image segmented into the 5X5 region. If the feature point is not included, it is processed as False and the corresponding area is blacked to remove unnecessary object information excluding the vehicle object. Then, the post processed area is set as the maximum search window size of the vehicle. And A minimum search window using the outermost feature points of the vehicle is set. By using the set search window, we compensate the disadvantages of the search window size of mean-shift algorithm and track vehicle object. In order to evaluate the performance of the proposed method, SIFT and SURF algorithms are compared and tested. The result is about four times faster than the SIFT algorithm. And it has the advantage of detecting more efficiently than the process of SUFR algorithm.

Soil Moisture Redistribution of Surface Drip Irrigation (점적관개에 따른 토양수분 재분배 평가)

  • Nam, Won-Ho;Choi, Soon-Goon;Hong, Eun-Mi;Yoo, Seung-Hwan;Choi, Jin-Yong;Jeon, Sang-Ho
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2011.05a
    • /
    • pp.469-469
    • /
    • 2011
  • 점적관개는 과수원이나 시설재배에서 수량 및 품질을 향상시키기 위해 물을 효율적으로 사용하여, 비료 및 농약 등에 의한 비점원 오염을 감소시킬 수 있는 방법으로 자주 고려되어 왔다. 효율적인 점적관개를 위해서는 관개시 토양의 수분 분포에 대한 정보가 필요하며, 이는 점적기의 간격, 관개수량 기준에 중요한 기초자료로 활용된다. 시설재배지에서 토양수분의 관리 및 관개를 위한 점적기 설치 간격, 유량은 현재 관리자의 경험적인 지식에 의존하고 있으며, 재배지 토성의 변화에 적절히 대응 할 수 있는 설계 기준 구축이 전무한 상태이다. 본 연구에서는 점적관개 시 토양수분 분포의 변화 양상을 국내토양 및 시설재배 현황을 반영하여 실험설계를 실시하였으며 토양수분 재분배 및 균일성 평가 방법을 적용하여, 적정 점적관개 시스템의 설계 및 운영에 필요한 기초자료를 제공하였다.

  • PDF

Analysis and Design of Security Policy Server Applied Security Management Interface (보안관리 인터페이스를 적용한 보안정책 서버 분석 및 설계)

  • Choi, Byoung-Son;Lee, Seoung-Hyeon;Lee, Won-Gu;Lee, Jae-Kwang
    • Proceedings of the Korea Information Processing Society Conference
    • /
    • 2003.11c
    • /
    • pp.1755-1758
    • /
    • 2003
  • 본 논문에서는 리눅스 상에 효율적인 보안 정책 관리를 위한 보안 정책 서버를 분석하고, 보안 정책 변경을 위한 인터페이스를 설계하였다. 리눅스는 소스가 공개된 운영체제이기 때문에, 보안상의 취약점을 이용하여 수많은 공격을 당하게 된다. 이러한 보안상의 문제를 해결하기 위하여 본 논문에서는 효율적인 정책 서버를 분석하여 리눅스에 적용함으로써, 리눅스가 가지는 보안상의 취약점을 해결하고자 하였다. 또한 관리자가 쉽게 정책을 적용할 수 있도록 보안 정책 적용을 위한 인터페이스를 설계하였다. 설계된 보안 정책 서버를 통하여 기존 리눅스 커널의 수정을 최소화하면서, 다른 접근제어 모델을 사용한 때에는 관련 모듈만 교체만 하면 되기 때문에 이미 설정된 보안 정책을 손쉽게 변화 할 수 있다

  • PDF

Attack Detection Technology through Log4J Vulnerability Analysis in Cloud Environments (클라우드 환경에서 Log4J 취약점 분석을 통한 공격 탐지 기술)

  • Byeon, Jungyeon;Lee, Sanghee;Yoo, Chaeyeon;Park, Wonhyung
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
    • /
    • 2022.05a
    • /
    • pp.557-559
    • /
    • 2022
  • The use of open source has the advantage that the development environment is convenient and maintenance is easier, but there is a limitation in that it is easy to be exposed to vulnerabilities from a security point of view. In this regard, the LOG4J vulnerability, which is an open source logging library widely used in Apache, was recently discovered. Currently, the risk of this vulnerability is at the 'highest' level, and developers are using it in many systems without being aware of such a problem, so there is a risk that hacking accidents due to the LOG4J vulnerability will continue to occur in the future. In this paper, we analyze the LOG4J vulnerability in detail and propose a SNORT detection policy technology that can detect vulnerabilities more quickly and accurately in the security control system. Through this, it is expected that in the future, security-related beginners, security officers, and companies will be able to efficiently monitor and respond quickly and proactively in preparation for the LOG4J vulnerability.

  • PDF

Fuzzy Logic-based Navigation Strategy of Mobile Robots with Obstacle Avoidance (퍼지논리를 이용한 이동로봇의 장애물회피 항법전략)

  • 최정원;권순학;이석규;이해영
    • Journal of the Korean Institute of Intelligent Systems
    • /
    • v.8 no.2
    • /
    • pp.35-42
    • /
    • 1998
  • 이동로봇이 주위환경에 대해서 전혀 알지 못하고 목표점으로 주행할때, 로봇은 긴 장애물이나 오목한 장애물에 대해서 존재할 수 있는 국부최소점에 빠져 더 이상 진행을 못하는 발생할수 있다. 본 논문에서는, 이 문제를 해결하기 위하여 퍼지 이론을 사용하여 효율적인 장애물회피와 안정된 목표점 도달을 달성할수 있도록하는 알고리즘을 제시한다. 제시된 알고리즘은 상하 2층 구조로 되어 있으며, 하위층은 장애물 회피 알고리즘 및 목표점 접근 알고리즘으로, 그리고 상위층은 로봇이 이동하면서 변화하는 환경에 맞게 앞의 두 알고리즘에 적절한 가중치를 부여하는 가중치 부여 알고리즘으로 구성되어 있다. 본 논문에서 제시된 알고리즘의 타당성을 보이기 위하여 'ㄹ', 'ㅊ' 형태의 장애물 및 여러 가지 형태의 장애물이 복합적으로 존재하는 환경에서 모의실험을 행한결과, 만족할 만한 결과를 얻을 수 있었다.

  • PDF

Real-time Vanishing Point Detection Using Histogram of Oriented Gradient (Histogram of Oriented Gradient를 이용한 실시간 소실점 검출)

  • Choi, Ji-Won;Kim, Chang-Ick
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.48 no.2
    • /
    • pp.96-101
    • /
    • 2011
  • Vanishing point can be defined as a point generated by converged perspective lines, which are parallel in the real world. In this paper, we propose a real-time vanishing point detection algorithm using this fundamental feature of vanishing point. The existing methods 1) require high computational cost or 2) are restricted to specific image contents. The proposed method detects the vanishing point in images based on the block-wise HOG (Histogram of Oriented Gradient) descriptor. First, we compute the HOG descriptor in a block-wise manner, then estimate the location of the vanishing point using the proposed dynamic programing. Experiments are performed on diverse images to confirm the efficiency of the proposed method.

Optimal Thresholds from Mixture Distributions (혼합분포에서 최적분류점)

  • Hong, Chong-Sun;Joo, Jae-Seon;Choi, Jin-Soo
    • The Korean Journal of Applied Statistics
    • /
    • v.23 no.1
    • /
    • pp.13-28
    • /
    • 2010
  • Assuming a mixture distribution for credit evaluation studies, we discuss estimating threshold methods to minimize errors that default borrowers are predicted as non defaults or non defaults are regarded as defaults. A method by using statistical hypotheses tests, the most powerful test and generalized likelihood ratio test, for the probability density functions which are defined with the score random variable and the parameter space consisted of only two elements such as the default and non default states is proposed to estimate a threshold. And anther optimal thresholds to maximize classification accuracy measures of the accuracy and the true rate for ROC and CAP curves are estimated as equations related with these probability density functions. Three kinds of optimal thresholds in terms of the hypotheses testing, the accuracy and the true rate are obtained from normal random samples with various means and variances. The sums of the type I and type II errors corresponding to each optimal threshold are obtained and compared. Finally we discuss about their efficiency and derive conclusions.

A Deblocking Filtering Method for Illumination Compensation in Multiview Video Coding (다시점 비디오 코딩에서 휘도 보상 방법에 적합한 디블록킹 필터링 방법)

  • Park, Min-Woo;Park, Gwang-Hoon
    • Journal of Broadcast Engineering
    • /
    • v.13 no.3
    • /
    • pp.401-410
    • /
    • 2008
  • Multiview Video Coding contains a macroblock-based illumination compensation tool which can compensate the variations of illuminations according to view or temporal directions. Thanks to illumination compensation tool, the coding efficiency of Multiview Video Coding has been enhanced. However illumination compensation tool also generates additional subjective drawbacks of the blocking artifacts due to macroblock-based compensations of mean values. A deblocking filtering method for Multiview Video Coding which is the same as in H.264/AVC does not consider illumination difference between the illumination compensated blocks, thus it can not effectively eliminate the blocking artifacts. Therefore, this paper analyzes the phenomena of blocking artifacts caused by illumination compensation and proposes a method which can effectively eliminate the blocking artifacts with the minimum changes of the H.264 deblockding filtering method. In the simulation results, it can be easily found the blocking artifacts are clearly eliminated in the subjective comparisons, and the average bit-rate reduction is up to 1.44%.

Performance Evaluation of Hydrogen Separation and Generator for Hydrogen Water (수소수를 위한 수소분리 및 생성기 성능 평가)

  • Kim, Gui-Jung;Han, Jung-Soo
    • Journal of Digital Convergence
    • /
    • v.14 no.9
    • /
    • pp.281-286
    • /
    • 2016
  • In this paper, we optimized the structure of hydrogen water generator and assessed by developing a generator with dissolved hydrogen amount(1,000~1,200 ppb) of world-class level. Evaluation is divided into four types, such as dissolved hydrogen amount, pH, maximum pressure, redox potential, and it was evaluated for each of the targets. It was performed through the experiment of four in all five times and all of them show superiority results appearing in the target range. In addition, the assessment got 25/30 functionality, 17/20 maintainability, 26/30 usability, and 19/20 efficiency. In particular, we proved the validity of this study in high efficiency. We developed this hydrogen water generator system as possible to be substitution of water purifier.