• Title/Summary/Keyword: detection technique

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A Study on the Revised Method using Normalized RGB Features in the Moving Object Detection by Background Subtraction (배경분리 방법에 의한 이동 물체 검출에서 개선된 색정보 정규화 기법에 관한 연구)

  • Park, Jong-Beom
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.12 no.6
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    • pp.108-115
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    • 2013
  • A developed skill of an intelligent CCTV is also advancing by using its Image Acquisition Device. In this field, area for technique can be divided into Foreground Subtraction which detects individuals and objects in a potential observing area and a tracing technology which figures out moving route of individuals and objects. In this thesis, an improved algorism for a settled engine development, which is stable to change in both noise and illumination for detecting moving objects is suggested. The proposed algorism from this thesis is focused on designing a stable and real time processing method which is perfect model in detecting individuals, animals, and also low-speeding transports and catching a change in an illumination and noise.

Localisation of embedded water drop in glass composite using THz spectroscopy

  • Mieloszyk, Magdalena;Majewska, Katarzyna;Ostachowicz, Wieslaw
    • Smart Structures and Systems
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    • v.21 no.6
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    • pp.751-759
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    • 2018
  • Glass fibre reinforced polymers (GFRP) are widely exploited in many industrial branches. Due to this Structural Health Monitoring systems containing embedded fibre optics sensors are applied. One of the problems that can influence on composite element durability is water contamination that can be introduced into material structure during manufacturing. Such inclusion can be a damage origin significantly decreasing mechanical properties of an element. A non-destructive method that can be applied for inspection of an internal structure of elements is THz spectroscopy. It can be used for identifications of material discontinuities that results in changes of absorption, refractive index or scattering of propagating THz waves. The limitations of THz propagation through water makes this technique a promising solution for detection of a water inclusion. The paper presents an application of THz spectroscopy for detection and localisation of a water drop inclusion embedded in a GFRP material between two fibre optics with fibre Bragg grating sensors. The proposed filtering method allowed to determine a 3D shape of the water drop.

Damage detection through structural intensity and vibration based techniques

  • Petrone, G.;Carzana, A.;Ricci, F.;De Rosa, S.
    • Advances in aircraft and spacecraft science
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    • v.4 no.6
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    • pp.613-637
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    • 2017
  • The development systems for the Structural Health Monitoring has attracted considerable interest from several engineering fields during the last decades and more specifically in the aerospace one. In fact, the introduction of those systems could allow the transition of the maintenance strategy from a scheduled basis to a condition-based approach providing cost benefits for the companies. The research presented in this paper consists of a definition and next comparison of four methods applied to numerical measurements for the extraction of damage features. The first method is based on the determination of the Structural Intensity field at the on-resonance condition in order to acquire information about the dissipation of vibrational energy throughout the structure. The Damage Quantification Indicator and the Average Integrated Global Amplitude Criterion methods need the evaluation of the Frequency Response Function for a healthy plate and a damaged one. The main difference between these two parameters is their mathematical definition and therefore the accuracy of the scalar values provided as output. The fourth and last method is based on the Mode-shape Curvature, a FRF-based technique which requires the application of particular finite-difference schemes for the derivation of the curvature of the plate. All the methods have been assessed for several damage conditions (the shape, the extension and the intensity of the damage) on two test plates: an isotropic (steel) plate and a 4-plies composite plate.

A Study on the Image Tamper Detection using Digital Signature (디지털 서명을 이용한 영상의 위변조 검출에 관한 연구)

  • Woo, Chan-Il
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.7
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    • pp.4912-4917
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    • 2015
  • Fragile watermarking is a technique to insert a watermark into an image without significantly degrading its visual quality so that the watermark can be extracted for the purposes of authentication or integrity verification. And the watermark for authentication and integrity verification should be erased easily when the image is changed by filtering etc. In this paper, we propose a image block-wise watermarking method for image tamper proofing using digital signature. In the proposed method, a digital signature is generated from the hash code of the initialized image block. And The proposed method is able to detect the tampered parts of the image without testing the entire block of the watermarked image.

Use of Molecular Detection Technique for Red Tide Warning of Cochlodinium polykrikoides (Cochlodinium polykrikoides 적조출현주의보 발령에 분자탐침기법의 활용)

  • PARK, TAE GYU;WON, KYOUNG MI;KIM, WON JIN
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.21 no.1
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    • pp.44-47
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    • 2016
  • Real-time PCR was applied to early warning of red tide. For early warning of red tide at $10cells\;mL^{-1}$, Cochlodinium polykrikoides specific real-time PCR was used as a complement of microscopy that has a lower detection sensitivity. C. polykrikoides appeared extensively in Tongyeong, Namhae waters at low densities in the end of June, and early warning of C. polyrkrikoides blooms was issued on 2 August 2015.

High-Speed Virtual Endoscopy using Improved Space-Leaping (개선된 공간 도약법을 이용한 고속 가상 내시경 기법)

  • Shin, Byeong-Seok;Jin, Ge
    • Journal of KIISE:Computer Systems and Theory
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    • v.29 no.8
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    • pp.463-471
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    • 2002
  • In order to implement virtual endoscopy, high-speed rendering algorithm that generates accurate perspective projection images and efficient collision detection method are essential. In this paper we propose an efficient virtual endoscopy system based on volume rendering technique. It is possible to skip over empty (transparent) space using the distance value produced in preprocessing time, and it does not deteriorate image quality since it is an extension of ray-casting. It also accelerates rendering speed with minimal loss of image quality by adjusting sampling interval along a ray according to direction of the ray. Using the distance information, we can simplify the collision detection of volumetric objects.

Extracellular Products from Cyanobacteria (시아노박테리아의 세포외산물에 대한 연구)

  • Kwon, Jong-Hee;Kim, Gi-Eun
    • KSBB Journal
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    • v.23 no.5
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    • pp.398-402
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    • 2008
  • Cyanobacteria havebeen identified as one of the most promising group producing novel biochemically active natural products. Cyanobacteria are a very old group of prokaryotic organisms that produce very diverse secondary metabolites, especially non-ribosomal peptide and polyketide structures. Though many useful natural products have been identified in cyanobacterial biomass, cyanobacteria produce also extracellular proteins related with NRPS/PKS. Detection of unknown secondary metabolites in medium was carried in the present study by a screening of 98 cyanobacterial strains. A degenerated PCR technique as molecular approaches was used for general screening of NRPS/PKS gene in cyanobacteria. A putative PKS gene was detected by DKF/DKR primer in 38 strains (38.8%) and PCR amplicons resulted from a presence of NRPS gene were showed by MTF2/MTR2 primer in 30 strains (30.6%) and by A3/A7 primer in 26 strains (26.5%). HPLC analysis for a detection of natural products was performed in extracts from medium in which cyanobacteria containing putative PKS or NRPS were cultivated. CBT57, CBT62, CBT590 and CBT632 strains were screened for a production of extracellular natural products. 5 pure substances were detected from medium of these cyanobacteria.

Reliability Evaluation of Aircraft Brake Disk using the Non-contact Air-coupled Ultrasonic Transducer Method (비접촉 초음파 탐상 기법을 이용한 항공기 브레이크 디스크의 신뢰성 평가)

  • Kwak, Nam-Su;Kim, Jae-Yeol;Gao, Jia-Chen;Park, Dae-Kwang
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.15 no.3
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    • pp.36-43
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    • 2016
  • Carbon fiber-reinforced silicon carbide (Cf-SiC) and SiC / SiC composites have high thermal conductivity, and excellent corrosion and wear resistance, a low coefficient for thermal expansion and are lightweight. This is why they are commonly used in parts of the aerospace industry to develop an aircraft thrust deflector, jet vane, combustion chamber, elevens, body flap, and a shingle. So, understanding how this state-of-the-art Cf-SiC affects both internal and external crack detection and determining issues during the manufacturing process of composite materials, should be evaluated according to valuation techniques in the external environment. In this paper, we apply a non-contact air ultrasonic technique of non-destructive testing techniques to perform a study on internal defect detection identification and assessment of carbon-fiber reinforced silicon carbide composites to perform basic research and applied research.

Detection of Enterovituses from Surface Water by Combined Cell Culture-PCR (지표수로부터 세포배양-연계 PCR법에 의한 장바이러스의 검출)

  • 정은영;정종문;류재익;신판세;전홍기;장경립
    • Journal of Life Science
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    • v.10 no.5
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    • pp.484-489
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    • 2000
  • Enterovirues may cause gastrointestinal symptoms, cold, and fever, mainly in young children. They are also recognized as important agents in acute infections of the central nervous system such as meningitis and encephalitis, and in subacute and chronic infections of the cardiovascular system such as pericarditis, myocarditis and cardiomyopathy. They also can lead to postviral fatigue syndrome. For the detection of enteroviruses from the environmental samples, the combined cell culture-polymerase chain reaction (CC-PCR) technique was employed. In contrast to EPA standard method which mainly depends on the cell culture, it involved the use of cell culture, followed by PCR to improve the sensitivity and the accuracy of the test. According to the results of survey, from 1999 to 2000, for the presence of enteroviruses in the surface water samples from Nak-dong river, four out of twelve samples were positive for viruses. The titer of viruses in the surface water was ranged from 25 to 250 MPN. All of the viruses isolated were poliovirus type I with 98% nucleotide sequence homology. The result also clearly suggests the seasonal difference in the distribution of the waterborne enteroviruses in surface water because most of the viruses were mainly detected from the summer through the early autumn.

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Measurements and Data Interpretation for the Detection of Steel Bars and Delamination inside Concrete (콘크리트내의 철근 및 공동탐사를 위한 측정과 분석)

  • Rhim, Hong-Chul;Park, Ki-Joon;Lee, Soong-Jae
    • Journal of the Korean Society for Nondestructive Testing
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    • v.20 no.4
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    • pp.305-313
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    • 2000
  • To determine detection capabilities of locating steel bars and delamination inside concrete, commercially available nondestructive testing (NDT) equipments have been tested. The equipments include two radar systems and two electromagnetic method systems. The inclusions are a 19 mm diameter steel bar and 50 mm thick delamination embedded at different cover depths from the surface of concrete specimens. For the steel bar, attempts were made to determine the size of the bars by changing the diameter of the bars. A sample result of measuring horizontal spacing between doubly reinforced bars is presented in this paper. Experimental results on various measurement cases are discussed. Application of numerical modeling technique for the simulation of radar measurements and improved output display of radar measurements are also presented.

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