• Title/Summary/Keyword: Spatial experiment

Search Result 778, Processing Time 0.028 seconds

Image Fingerprinting Scheme for Print-and-capture Attacking Model (Print-and-capture 공격 모델을 위한 이미지 핑거프링팅 기법)

  • Lee, Seon-Hwa;Kim, Won-Gyum;Seo, Yong-Seok
    • Proceedings of the IEEK Conference
    • /
    • 2006.06a
    • /
    • pp.427-428
    • /
    • 2006
  • This paper presents an image fingerprinting scheme for the print-to-capture model performed by a photo printer and digital camera. When capturing an image by a digital camera, various kinds of distortions such as noise, geometrical distortions, and lens distortions are applied. slightly and simultaneously. In this paper, we consider several steps to extract fingerprints from the distorted image in print-and capture scenario. To embed ID into an image as a fingerprint, multi-bits embedding is applied. We embed 64 bits information as a fingerprint into spatial domain of color images. In order to restore a captured image from distortions a noise reduction filter is performed and a rectilinear tiling pattern is used as a template. To make the template, a multi-bits fingerprint is embedded repeatedly like a tiling pattern. We show that the extracting is successful from the image captured by a digital camera through the experiment.

  • PDF

Analysis of Electromagnetically cCoupled Microstrip Transverse Dipole using Finite Difference Time Domain (FDTD) Method (시간영역 유한차분법을 이용한 전자기결합 마이크로스트립 수직다이폴의 해석)

  • 손영수;윤현보
    • The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.5 no.4
    • /
    • pp.30-39
    • /
    • 1994
  • The resonant frequency, reflection cofficient and input impedance of a microstrip transverse dipole coupled electromagnetically are calculated using Finite Difference Time Domain(FDTD) method, and the evolution of gaussian pulse and spatial distribution of electromagnetic field components in the computation domain is represented graphically. Also, we confirmed the computation results show good agreement with the results of Method of Moment(MOM) and experiment[8] reported in the literature.

  • PDF

Detection of Human Vital Signs and Estimation of Direction of Arrival Using Multiple Doppler Radars

  • An, Yong-Jun;Jang, Byung-Jun;Yook, Jong-Gwan
    • Journal of electromagnetic engineering and science
    • /
    • v.10 no.4
    • /
    • pp.250-255
    • /
    • 2010
  • This paper presents a non-contact measurement method of vital signal by the use of multiple-input multiple-output (MIMO) bio-radar system, configured with two antennas that are separated by a certain distance. The direction of arrival (DOA) estimation algorithm for coherent sources was applied to detect vital signals coming from different spatial angles. The proposed MIMO bio-radar system was composed of two identical transceivers sharing single VCO with a PLL. In order to verify the performance of the system, the DOA estimation experiment was completed with respect to the human target at angles varying between $-50^{\circ}$ and $50^{\circ}$ where the bio-radar system was placed at distances (corresponding to 50 cm and 95 cm) in front of a human target. The proposed MIMO bio-radar system can successfully find the direction of a human target.

Accurate Prediction Method of Breakdown Voltage in Air at Atmospheric Pressure

  • Kim, Nam-Kyung;Lee, Se-Hee;Georghiou, G.E.;Kim, Dong-Wook;Kim, Dong-Hun
    • Journal of Electrical Engineering and Technology
    • /
    • v.7 no.1
    • /
    • pp.97-102
    • /
    • 2012
  • To predict accurately the breakdown voltage in air at atmospheric pressure, a fully coupled finite element analysis combining the hydrodynamic diffusion-drift equations with Poisson's equation is proposed in the current paper. As three kinds of charged transport particles are nonlinearly coupled with spatial electric fields, the equations should be solved by an iterative numerical scheme, in which secondary effects, such as photoemission and photoionization, are considered. The proposed method has been successfully applied to evaluate the breakdown voltage in circular parallel-plane electrodes. Its validity has been proved through the comparison of the predicted and experimental results. The effects of numerical conditions of the initial charge, photoemission, and background ionization on the discharge phenomena are quantitatively assessed through Taguchi's design of experiment method.

Changes in the Optogalvanic Signal Amplitude in a Hollow Cathode Discharge

  • Lee, Jun-Hoi;Koo, Kyung-Wan;Lee, Ki-Sik
    • Transactions on Electrical and Electronic Materials
    • /
    • v.10 no.6
    • /
    • pp.212-216
    • /
    • 2009
  • The spatial distribution of the optogalvanic (OG) signal in argon at the 801.489 nm ($1s_5-2p_8$ transition at the metastable level in Paschen notation) was investigated in the radial direction of a hollow cathode discharge tube. The results of this experiment showed that the OG signal amplitude decreases in accordance with the following two conditions; first, the level of discharge current and second, the distance from the cathode dark space. These results can be quantified by analyzing the electron density profile along the discharge regions, which can directly influence the collisional ionization induced by electron impact.

Eye-hand coordination in press task (프레스 작업에서 눈과 손의 협응동작에 대한 연구)

  • 박경수;김유창
    • Journal of the Ergonomics Society of Korea
    • /
    • v.16 no.1
    • /
    • pp.63-71
    • /
    • 1997
  • This paper presented an experiment which examined eye and hand movement characteristics of novice and experienced workers in the press operation. Continuous recordings of eye and hand movements were made on five novice operators and five experienced operators in press operation. Significant difference between the novice and the experienced operators was observed in eye fixation time, eye movement patterns, hand dwell time, and eye-hand coordination. Also, differences were observed in spatial distribution of eye fixations during the die-closing portion of a stroke. There were no significant differences between the novice and the experiencedoperators in the eye and the hand movement time. The results could be used to establish a guide determining the method and training period to train the novice operators.

  • PDF

Shot Group and Representative Shot Frame Detection using Similarity-based Clustering

  • Lee, Gye-Sung
    • Journal of the Korea Society of Computer and Information
    • /
    • v.21 no.9
    • /
    • pp.37-43
    • /
    • 2016
  • This paper introduces a method for video shot group detection needed for efficient management and summary of video. The proposed method detects shots based on low-level visual properties and performs temporal and spatial clustering based on visual similarity of neighboring shots. Shot groups created from temporal clustering are further clustered into small groups with respect to visual similarity. A set of representative shot frames are selected from each cluster of the smaller groups representing a scene. Shots excluded from temporal clustering are also clustered into groups from which representative shot frames are selected. A number of video clips are collected and applied to the method for accuracy of shot group detection. We achieved 91% of accuracy of the method for shot group detection. The number of representative shot frames is reduced to 1/3 of the total shot frames. The experiment also shows the inverse relationship between accuracy and compression rate.

Measurement Range Enlargement in Brillouin Optical Correlation Domain Analysis Using Multiple Correlation Peaks

  • Jeong, Ji Ho;Lee, Kwanil;Jeong, Je-Myung;Lee, Sang Bae
    • Journal of the Optical Society of Korea
    • /
    • v.16 no.3
    • /
    • pp.210-214
    • /
    • 2012
  • We propose and experimentally demonstrate a method for extension of measurement range in a Brillouin optical correlation domain analysis sensor system without resolution deterioration. In the experiment, a 300 m measurement range with about 8 cm spatial resolution was successfully obtained by cascading three different kinds of fibers as a sensing element.

The Learning of the Neural Network Using Hadamard Transform

  • Katayama, Hiromu;Tsuruta, Shinchi;Nakao, Tomohiro;Harada, Hisamochi;Konishi, Ryosuke
    • Proceedings of the Korean Institute of Intelligent Systems Conference
    • /
    • 1993.06a
    • /
    • pp.1125-1128
    • /
    • 1993
  • We propose the new method about the neural-based pattern recognition by using Hadamard transform for the improvement of learning speed, stability and flexibility of network. We can obtain the spatial feature of pattern by Hadamard transformed pattern. We carried out an experiment to estimate the effect of Hadamard transform. We tried the learning of numeric patterns, and tried the pattern recognition with noisy pattern. As a result, the learning times of the network for the 'Hadamard' case is smaller than that of usual case. And the recognition rate of the network for the 'Hadamard' case is higher than that of usual case, too.

  • PDF

A Study on the Fire Safety Design and Predicting Fire Behavior Using Compartment Fire Test (단일화재실험을 통한 화재성상예측 및 건축구조물의 화재안전 설계에 관한 연구)

  • Yoon, Ung-Gi;Seo, Dong-Goo;Kim, Dong-Eun;Kwon, Young-Jin
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2013.05a
    • /
    • pp.107-108
    • /
    • 2013
  • In this study, combustibles investigation and fire growth rate experiment were performed for predicting initial fire behavior in buildings. Combustibles investigation was performed for residential buildings, which is most frequently affected by fire in Korea. Spatial characteristics and combustibles properties were separately investigated, and occupied area and layout characteristics of combustibles were identified to produce general layout models. Of the layout models, room was selected for fire test of a single compartment. From this test, fire propagation for each combustible was identified, which was delayed compared to the summed heat release rate of a single combustible.

  • PDF