• 제목/요약/키워드: Out of distribution detection

검색결과 204건 처리시간 0.029초

연속하는 공간적 특징의 시간적 유사성 검출을 이용한 고속 동영상 검색 (Fast Video Detection Using Temporal Similarity Extraction of Successive Spatial Features)

  • 조아영;양원근;조주희;임예은;정동석
    • 한국통신학회논문지
    • /
    • 제35권11C호
    • /
    • pp.929-939
    • /
    • 2010
  • 멀티미디어 기술이 발전함에 따라 대용량의 데이터베이스의 관리와 불법 복제물 검출을 위한 동영상 검색의 필요성이 커지고 있다. 본 논문에서는 이러한 요구에 맞춰 대용량 데이터베이스에서 고속 동영상 검색을 수행할 수 있는 방법을 제안한다. 고속 동영상 검색 방법은 프레임의 휘도 분포를 이용하여 공간적 특징을 추출하고, 동영상의 시간적 유사성 지도를 생성하여 시간적 특정을 추출한다. 동영상의 공간적 특정과 시간적 특정을 식별자로 구성하고 단계적인 정합 방법을 수행한다. 실험에서는 원본 동영상과 밝기 변화, 압축률 변환, 자막/로고 삽입과 같은 다양한 변형을 이용하여 정확성, 추출 및 정합 속도, 식별자 크기를 측정하여 성능을 평가하였다. 또한, 제안한 방법의 파라미터를 실험적으로 선택한 과정을 기술하고 비교 알고리즘과 공간적 특정만을 이용한 단순 정합 결과를 제시하였다. 정확성, 경색 속도 식별자 크기의 모든 결과에서, 제안한 고속 검색 방법이 대용량 데이터베이스의 동영상 경색에 가장 적합한 기술임을 보였다.

Fuzzy Color Classifier 와 Convex-hull을 사용한 얼굴 검출 (Face detection using fuzzy color classifier and convex-hull)

  • 박민식;박창우;김원하;박민용
    • 대한전자공학회논문지SP
    • /
    • 제39권2호
    • /
    • pp.69-78
    • /
    • 2002
  • 본 논문에서는 복잡한 배경에서의 얼굴 추출 방법을 제안한다. 제안된 알고리즘은 적응 퍼지 색 분할기법을 사용하여 얼굴색과 머리색을 분할시킨다. 얼굴색 분포는 Y,Cb,Cr 색 공간내에서 유도되어지고, 조명값에 적응적인 퍼지 시스템을 사용하여 얼굴색을 구분해낸다. 머리색은 RGB 색 공간내에서 구분되어진다. 전처리 과정을 거쳐 추출되어진 얼굴색과 머리색 영역에 컨벡스 헐을 적용하여 그들의 관계를 통해 최종적인 얼굴 영역이 추출되어진다. 제안된 방법은 기존의 패턴 매칭 방법에 비해 효율적인 성능을 나타낸다. 제안된 알고리즘의 유효성을 실험을 통해 증명하며, 색 영역에서의 제한 조건 없이 성공적으로 얼굴 영역을 추출해 냄을 알 수 있다.

RAPD 분석법을 이용한 산삼, 웅담, 녹용 등의 한약재 판별연구 (Identification study of rare and high-priced natural products used for oriental medicine by RAPD analysis)

  • 조동욱
    • 한국한의학연구원논문집
    • /
    • 제1권1호
    • /
    • pp.471-476
    • /
    • 1995
  • Natural products used for oriental medicine often come from various geographical sources, after several different distribution channels. Therefore some form of quality control procedure is required to safeguard naturl products for prescriptions purposes. To achieve this, systematic apprroaches such as morphological examination, microscopic analysis of powdered herbs and chemical analysis can be carried out. However, to ensure absolute criteria for quality assurance of natural products, DNA fingerprinting method such as RAPD(Random amplified polymorphism DNA) analysis can be used for authentication of natural products for authenticatin of natural products. In this study, warious oligonucleotide primers will be synthesized for the detection of RAPD markers and also parameters of affecting PCR(Polymerase Chain Reaction) in the detection of RAPD markers of rare and high-priced natural products will be studied with genomic DNA of chosen samples.

  • PDF

분산형전원이 도입된 배전계통에 대한 ISLANDING DETECTION METHOD (Islanding Detection Method of Embedded Generator connected to Power Distribution System)

  • 황진수;김재언
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2000년도 하계학술대회 논문집 A
    • /
    • pp.522-524
    • /
    • 2000
  • The installation of small sized Embedded Generator(EG) in parallel with the utility supply was required several technical complications for protection of the system. One of the most important protection is to provide protection against islanding and out of synchronism reclosing with the utility source. This paper explains several current methods of detecting 'Loss Of Mains'(LOM). But they have not proved completely dependable, in particular when the islanded load's capacity matches that of the EG. A new loss of mains protection algorithm is presented in this paper which based on measurement of the reactive power and node voltage for detecting the islanding condition even though the EG operate in the capacity.

  • PDF

배전급 CNC케이블의 결함 종류에 따른 부분방전 분포특성 (Partial Discharge Distribution Characteristics along Defect of CNC Cable)

  • 윤재훈;강성화;최한식;임기조
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2010년도 하계학술대회 논문집
    • /
    • pp.102-102
    • /
    • 2010
  • A purpose of this paper is to recognize partial discharge pattern for cable insulation. The classification of PD sources was widely studied for two decades. this research sought to use the partial discharge detection method, and to diagnose the interface of cable, which is deemed vulnerable of cable systems. A research abalyzed faults that can occur in the interface of cable joint as well as accident mechanisms, manufactured test 22.9kV CNC cable, invented artificial faults and carried out partial discharge detection experiments. As a result, various PD pattern along defect measured and distinguished.

  • PDF

A Novel Detection Technique for Voltage Sag in Distribution Lines Using the Wavelet Transform

  • Ko, Young-Hun;Kim, Chul-Hwan;Ahn, Sang-Pil
    • KIEE International Transactions on Power Engineering
    • /
    • 제3A권3호
    • /
    • pp.130-138
    • /
    • 2003
  • This paper presents a discrete wavelet transform approach for determining the beginning and end times of voltage sags. Firstly, investigations in the use of some typical mother wavelets, namely Daubechies, Symlets, Coiflets and Biorthogonal are carried out and the most appropriate mother wavelet is selected. The proposed technique is based on utilizing the maximum value of Dl (at scale 1) coefficients in multiresolution analysis (MRA) based on the discrete wavelet transform. The results are compared with other methods for determining voltage sag duration, such as the Root Mean Square (RMS) voltage and Short Time Fourier Transform (STFT) methods. It is shown that the voltage sag detection technique based on the wavelet transform is a satisfactory and reliable method for detecting voltage sags in power quality disturbance analysis.

변전소 상태추정 및 고장 측정기기의 검정 시뮬레이터에 관한 연구 (A Study on the Substation Simulator for the State Estimation and the Bad Measuring Devices Detection)

  • 이흥재;왕인수;김용한;박성민;강현재
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2000년도 하계학술대회 논문집 A
    • /
    • pp.116-118
    • /
    • 2000
  • The modern power system including lots of measuring devices and controller is large and complex total information system. A Lot of data and system information are transmitted to operators, and analysing these information and system management is very important. Recently, GUI(Graphic Users Interface) is emphasized as a method that operators carry out their duties, effectively. In this paper. a simulator that can show state estimation and detection of bad measuring devices is introduced for domestic 154kV/22.9kV distribution substations. C language and Visual Basic is used for this simulator. and TCP/IP is adopted to consider connection with a Power system.

  • PDF

Detection of flaw in steel anchor-concrete composite using high-frequency wave characteristics

  • Rao, Rajanikant;Sasmal, Saptarshi
    • Steel and Composite Structures
    • /
    • 제31권4호
    • /
    • pp.341-359
    • /
    • 2019
  • Non-monolithic concrete structural connections are commonly used both in new constructions and retrofitted structures where anchors are used for connections. Often, flaws are present in anchor system due to poor workmanship and deterioration; and methods available to check the quality of the composite system afterward are very limited. In case of presence of flaw, load transfer mechanism inside the anchor system is severely disturbed, and the load carrying capacity drops drastically. This raises the question of safety of the entire structural system. The present study proposes a wave propagation technique to assess the integrity of the anchor system. A chemical anchor (embedded in concrete) composite system comprising of three materials viz., steel (anchor), polymer (adhesive) and concrete (base) is considered for carrying out the wave propagation studies. Piezoelectric transducers (PZTs) affixed to the anchor head is used for actuation and the PZTs affixed to the surrounding concrete surface of the concrete-anchor system are used for sensing the propagated wave through the anchor interface to concrete. Experimentally validated finite element model is used to investigate three types of composite chemical anchor systems. Studies on the influence of geometry, material properties of the medium and their distribution, and the flaw types on the wave signals are carried out. Temporal energy of through time domain differentiation is found as a promising technique for identifying the flaws in the multi-layered composite system. The present study shows a unique procedure for monitoring of inaccessible but crucial locations of structures by using wave signals without baseline information.

Audit Expectation Gap: Empirical Evidence from Vietnam

  • NGUYEN, Hieu Thanh;NGUYEN, Anh Huu
    • The Journal of Asian Finance, Economics and Business
    • /
    • 제7권5호
    • /
    • pp.51-60
    • /
    • 2020
  • The paper examines the characteristics and causes of the expectation gap of audit and assurance services. The paper has conducted three surveys with three target groups. In the first survey, participants are auditors, users of audit reports are subject in the second survey and in the third survey, and students major in auditing are selected. The content of the survey aims to find out the differences in perception of the survey participants on two issues: (i) responsibilities of auditors for detection frauds, errors, protection of the enterprise's assets and financial scandals, and (ii) the role of audit and auditors in making investment decisions and investor's belief. The research carried out survey from March to September 2019 with 165 responds. The collected data was processed by statistical software SPSS, version 23, and Mann-Whitney U test was used to analyze the results of the audit expectation gap between the auditor group and the users of audit report group and between the student group and users of audit report group. The results showed that there exists an expectation gap in the responsibility of auditors for detection of all frauds, errors and protection enterprise's assets. Recommendations include strengthening audit standards, penalizing bad practices and ensuring auditor's independence.

연직관측자료를 통한 복잡 연안지역의 오존 이류특성 (Characteristics of Ozone Advection in Vertical Observation Analysis Around Complex Coastal Area)

  • 이화운;박순영;이순환;임헌호
    • 한국대기환경학회지
    • /
    • 제25권1호
    • /
    • pp.57-74
    • /
    • 2009
  • In order to clarify the vertical ozone distribution in planetary boundary layer of coastal area with complex terrain, an observation campaign was carried out around Gwangyang Bay with dense pollutant emission sources during two days from June, 4 2007. For this observation are Radiosonde, SODAR(SOnic Detection And Ranging) and Tethered ozone sonde were employed. The surface meteorological and photochemical observation data provided by AWS (Automatic Weather System) and AQMS (Air Quality Monitoring System) were also applied for analysis. Synoptic condition is strongly associated with lower level ozone distribution in complex terrain coastal area. Since mesoscale circulation induced by difference of characteristics of land and sea and orographic forcing is predominant under calm synoptic condition, vertical distribution of ozone is complicate and vertical ozone concentration greatly fluctuated. However in second day when synoptic influence become strong, ozone concentration in lower levels is vertically uniform regardless of observation level. This results in vertical observation indicates that vertical ozone distribution is often determined by synoptic condition and also affects surface ozone concentration.