• 제목/요약/키워드: Convergence Structure

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디지털 정보전에 대비한 국방정보보호업무 관리구조에 관한 연구 (A Study on Defense Information Security Management Structure for Digital Information Warfare)

  • 권문택
    • 융합보안논문지
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    • 제8권4호
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    • pp.57-63
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    • 2008
  • 본 연구는 미래 정보전에 대비하기 위한 대책의 일환으로 전군적 차원에서 체계적인 정보보호 업무 수행체계를 수립하기 위한 방안을 제시하기 위한 것이다. 미국, 일본 등 선진국들은 미래 정보전에 대처할 수 있는 새로운 안보전략을 수립하다. 그러나 한국군은 비록 정보화 사업을 꾸준히 추진하여 왔으나 정보전 위협에 대한 대비는 매우 미흡한 실정이다. 본 연구는 이러한 취약점에 대비하고자 국방정보체계 분야 전문가에 의한 그룹의사결정기법을 활용하여 국방정보 보호 업무 관리 구조 방안을 도출하여 제시하였다. 본 연구에서 제시하는 업무수행 구조에 따라 정보보호업무 구조를 정립하고 수행한다면 보다 완벽한 정보보호 대책을 마련할 수 있을 것이다.

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Infrared Target Extraction Using Weighted Information Entropy and Adaptive Opening Filter

  • Bae, Tae Wuk;Kim, Hwi Gang;Kim, Young Choon;Ahn, Sang Ho
    • ETRI Journal
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    • 제37권5호
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    • pp.1023-1031
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    • 2015
  • In infrared (IR) images, near targets have a transient distribution at the boundary region, as opposed to a steady one at the inner region. Based on this fact, this paper proposes a novel IR target extraction method that uses both a weighted information entropy (WIE) and an adaptive opening filter to extract near finely shaped targets in IR images. Firstly, the boundary region of a target is detected using a local variance WIE of an original image. Next, a coarse target region is estimated via a labeling process used on the boundary region of the target. From the estimated coarse target region, a fine target shape is extracted by means of an opening filter having an adaptive structure element. The size of the structure element is decided in accordance with the width information of the target boundary and mean WIE values of windows of varying size. Our experimental results show that the proposed method obtains a better extraction performance than existing algorithms.

Initial Timing Acquisition for Binary Phase-Shift Keying Direct Sequence Ultra-wideband Transmission

  • Kang, Kyu-Min;Choi, Sang-Sung
    • ETRI Journal
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    • 제30권4호
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    • pp.495-505
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    • 2008
  • This paper presents a parallel processing searcher structure for the initial synchronization of a direct sequence ultra-wideband (DS-UWB) system, which is suitable for the digital implementation of baseband functionalities with a 1.32 Gsample/s chip rate analog-to-digital converter. An initial timing acquisition algorithm and a data demodulation method are also studied. The proposed searcher effectively acquires initial symbol and frame timing during the preamble transmission period. A hardware efficient receiver structure using 24 parallel digital correlators for binary phase-shift keying DS-UWB transmission is presented. The proposed correlator structure operating at 55 MHz is shared for correlation operations in a searcher, a channel estimator, and the demodulator of a RAKE receiver. We also present a pseudo-random noise sequence generated with a primitive polynomial, $1+x^2+x^5$, for packet detection, automatic gain control, and initial timing acquisition. Simulation results show that the performance of the proposed parallel processing searcher employing the presented pseudo-random noise sequence outperforms that employing a preamble sequence in the IEEE 802.15.3a DS-UWB proposal.

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자동 겐트리 로봇의 용접 흄 유동 및 구조해석 - CFD/CAE 및 자동화 융합 연구 - (Flow and Structural Analysis at Welding Fume of Automatic Gantry Robot - CFD/CAE and Automatic Convergence Study -)

  • 장성철
    • 한국기계가공학회지
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    • 제11권6호
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    • pp.158-163
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    • 2012
  • This study investigates numerical analysis for robot welder fume flow and gantry structure. The solvers are STAR-CCM+ and ANSYS workbench used on flow and structural analysis. The results show that fume is diffused in factory when the welding fume is remove at dust collector. But dust collector intercepts the fume diffusion into workroom by removing most of welding fume. Structure analysis result shows that the reinforcement rod is evaluated to main the safety by supporting sufficient structure.

DVR 모니터의 동특성 향상을 위한 구조 개선에 관한 연구 (Design Alteration of a Security DVR Monitor Structure for the Improved Dynamic Stabilty)

  • 김건형;이원규;이태훈;노승훈;정평수
    • 한국산업융합학회 논문집
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    • 제13권2호
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    • pp.63-68
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    • 2010
  • Structural vibrations are among the biggest concerns in developing high resolution DVR(Digital Video Recorder) monitors. The vibrations in DVR monitors are mostly originated from the excitation sources such as the HDD and the cooling fan. In this study, the vibrations generated from the excitation sources were investigated in order to analyze the individual effect on the structural vibrations of the monitors and further to establish the design alteration to suppress the vibrations for the stability of the structure and for the better quality of the screen. The result shows that relatively simple design alterations can improve the stability of the structure substantially.

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극한 환경에서의 비대면 작업을 위한 소비자 친화형 포크리프트 구조의 5축 매니퓰레이터의 유압제어 시스템 설계 및 성능분석에 대한 연구 (A Study on Performance Analysis and Hydraulic Control System Design of Forklift Structure Manipulator with 5 Joints for Untact Working in Limited Environment)

  • 김희진;김성일;한성현;윤경화
    • 한국산업융합학회 논문집
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    • 제25권3호
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    • pp.477-491
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    • 2022
  • This study proposed the performance analysis and hydraulic control system design of forklift structure manipulator with 5 joints for untact working in lilited environment. The performance analysis of the control system analyzed the control response to load and pressure fluctuations. The reliability of proposed control system was verified by simulation test under the various condition.

Optimized Location Selection of Active Mounting System Applied to 1D Beam Structure

  • Kim, Byeongil
    • 한국산업융합학회 논문집
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    • 제25권4_1호
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    • pp.505-511
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    • 2022
  • The objective of this article is finding optimized locations of active mounts applied to 6-DOF beam structure with two active paths. When sinusoidal excitation forces are applied to the beam structure, secondary forces from two active mounts which can minimize (ideally becoming zero) transmitted forces are calculated mathematically and the vibration attenuation performance is validated through computer simulations. When the force applied to two active mounts are relatively low, those specific locations are considered as optimized location of active mounting system. As the location of mount changes, amplitude and phase of secondary forces in each path are analyzed with 3D plots. Based on the simulation results, a criterion for selecting mounting location is suggested and it would be very useful for selecting actuators for active mounts appropriately.

Estimation of Noise Level and Edge Preservation for Computed Tomography Images: Comparisons in Iterative Reconstruction

  • Kim, Sihwan;Ahn, Chulkyun;Jeong, Woo Kyoung;Kim, Jong Hyo;Chun, Minsoo
    • 한국의학물리학회지:의학물리
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    • 제32권4호
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    • pp.92-98
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    • 2021
  • Purpose: This study automatically discriminates homogeneous and structure edge regions on computed tomography (CT) images, and it evaluates the noise level and edge preservation ratio (EPR) according to the different types of iterative reconstruction (IR). Methods: The dataset consisted of CT scans of 10 patients reconstructed with filtered back projection (FBP), statistical IR (iDose4), and iterative model-based reconstruction (IMR). Using the 10th and 85th percentiles of the structure coherence feature, homogeneous and structure edge regions were localized. The noise level was estimated using the averages of the standard deviations for five regions of interests (ROIs), and the EPR was calculated as the ratio of standard deviations between homogeneous and structural edge regions on subtraction CT between the FBP and IR. Results: The noise levels were 20.86±1.77 Hounsfield unit (HU), 13.50±1.14 HU, and 7.70±0.46 HU for FBP, iDose4, and IMR, respectively, which indicates that iDose4 and IMR could achieve noise reductions of approximately 35.17% and 62.97%, respectively. The EPR had values of 1.14±0.48 and 1.22±0.51 for iDose4 and IMR, respectively. Conclusions: The iDose4 and IMR algorithms can effectively reduce noise levels while maintaining the anatomical structure. This study suggested automated evaluation measurements of noise levels and EPRs, which are important aspects in CT image quality with patients' cases of FBP, iDose4, and IMR. We expect that the inclusion of other important image quality indices with a greater number of patients' cases will enable the establishment of integrated platforms for monitoring both CT image quality and radiation dose.

A 9-Bit 80-MS/s CMOS Pipelined Folding A/D Converter with an Offset Canceling Technique

  • Lee, Seung-Chul;Jeon, Young-Deuk;Kwon, Jong-Kee
    • ETRI Journal
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    • 제29권3호
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    • pp.408-410
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    • 2007
  • A 9-bit 80-MS/s CMOS pipelined folding analog-to-digital converter employing offset-canceled preamplifiers and a subranging scheme is proposed to extend the resolution of a folding architecture. A fully differential dc-decoupled structure achieves high linearity in circuit design. The measured differential nonlinearity and integral nonlinearity of the prototype are ${\pm}0.6$ LSB and ${\pm}1.6$ LSB, respectively.

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EXPONENTIAL INEQUALITIES AND COMPLETE CONVERGENCE OF EXTENDED ACCEPTABLE RANDOM VARIABLES

  • Choi, Jeong-Yeol;Baek, Jong-Il
    • Journal of applied mathematics & informatics
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    • 제31권3_4호
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    • pp.417-424
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    • 2013
  • Giuliano Antonini et al.(2008) have introduced the concept of extended acceptability and the results show that the extended acceptability structure has no effect on the exponential inequality except replacing a constant M = 1 with a constant M > 0. We discuss the complete convergence for extended acceptable random variables by using the exponential inequality.