• 제목/요약/키워드: Source signatures

검색결과 49건 처리시간 0.024초

수중 이동체의 전기장 신호 기반 위치추정을 위한 수중 전기장 배열센서의 전극 부설 위치 오차 보정 방법 (Calibrating Electrode Misplacement in Underwater Electric Field Sensor Arrays for the Electric Field-Based Localization of Underwater Vessels)

  • 김재선;이인규;배기웅;유선철
    • 센서학회지
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    • 제31권5호
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    • pp.330-336
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    • 2022
  • This paper proposes a method to calibrate the electrode misplacement in underwater electric field sensor arrays (EFSAs) for accurate measurements of underwater electric field signatures. The electrode misplacement of an EFSA was estimated by measuring the electric field signatures generated by a known electric source and by comparing the measurements with the theoretical calculations under similar measurement conditions. When the EFSA measured the electric field signatures induced by an unknown electric source, the electric properties of the unknown electric source were approximated by considering the optimized estimation of the electrode misplacement of the EFSA. Finally, the measured electric field signatures were calibrated by calculating the theoretical electric field signatures to be measured with an ideally installed EFSA without electrode misplacement; the approximated electric properties of the unknown electric source were also taken into account. Simulations were conducted to test the proposed calibration method. The results showed that the electrode misplacement could be estimated. Further, the electric field measurements and the electric field-based localization of underwater vessels became more accurate after the application of the proposed calibration method. The proposed method will contribute to applications such as the detection and localization of underwater electric sources, which require accurate measurements of underwater electric field signatures.

SplitScreen: Enabling Efficient, Distributed Malware Detection

  • Cha, Sang-Kil;Moraru, Iulian;Jang, Ji-Yong;Truelove, John;Brumley, David;Andersen, David G.
    • Journal of Communications and Networks
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    • 제13권2호
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    • pp.187-200
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    • 2011
  • We present the design and implementation of a novel anti-malware system called SplitScreen. SplitScreen performs an additional screening step prior to the signature matching phase found in existing approaches. The screening step filters out most non-infected files (90%) and also identifiesmalware signatures that are not of interest (99%). The screening step significantly improves end-to-end performance because safe files are quickly identified and are not processed further, and malware files can subsequently be scanned using only the signatures that are necessary. Our approach naturally leads to a network-based anti-malware solution in which clients only receive signatures they needed, not every malware signature ever created as with current approaches. We have implemented SplitScreen as an extension to ClamAV, the most popular open source anti-malware software. For the current number of signatures, our implementation is $2{\times}$ faster and requires $2{\times}$ less memory than the original ClamAV. These gaps widen as the number of signatures grows.

화강암류의 성인 해석에 대한 마그네슘 동위원소 자료의 활용 (Use of Magnesium Stable Isotope Signatures for the Petrogenetic Interpretation of Granitic Rocks)

  • 정창식;류종식
    • 암석학회지
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    • 제23권3호
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    • pp.221-227
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    • 2014
  • 최근 분석법의 발달에 따라 금속 안정동위원소의 지질학적인 활용이 두드러지고 있다. 이 논평에서는 Mg 동위원소 분석 자료를 화강암류의 성인 해석에 활용하는 원리와 분석 방법, 적용의 예를 소개한다. 먼저 Mg 동위원소가 분별되는 원리를 설명하고 다검출기 유도결합 플라즈마 질량분석기를 활용한 분석 방법을 기술하며 마지막으로 북미 서해안과 호주, 중국의 I형, S형, A형 화강암에 대한 최근의 적용 사례를 살펴볼 것이다.

Tissue proteomics for cancer biomarker development - Laser microdissection and 2D-DIGE -

  • Kondo, Tadashi
    • BMB Reports
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    • 제41권9호
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    • pp.626-634
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    • 2008
  • Novel cancer biomarkers are required to achieve early diagnosis and optimized therapy for individual patients. Cancer is a disease of the genome, and tumor tissues are a rich source of cancer biomarkers as they contain the functional translation of the genome, namely the proteome. Investigation of the tumor tissue proteome allows the identification of proteomic signatures corresponding to clinico-pathological parameters, and individual proteins in such signatures will be good biomarker candidates. Tumor tissues are also a rich source for plasma biomarkers, because proteins released from tumor tissues may be more cancer specific than those from non-tumor cells. Two-dimensional difference gel electrophoresis (2D-DIGE) with novel ultra high sensitive fluorescent dyes (CyDye DIGE Fluor satulation dye) enables the efficient protein expression profiling of laser-microdissected tissue samples. The combined use of laser microdissection allows accurate proteomic profiling of specific cells in tumor tissues. To develop clinical applications using the identified biomarkers, collaboration between research scientists, clinicians and diagnostic companies is essential, particularly in the early phases of the biomarker development projects. The proteomics modalities currently available have the potential to lead to the development of clinical applications, and channeling the wealth of produced information towards concrete and specific clinical purposes is urgent.

Analysis of Storage and Retrieval Results of Audio Sources and Signatures using Blockchain and Distributed Storage System

  • Lee, Kyoung-Sik;Kim, Sang-Kyun
    • 방송공학회논문지
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    • 제24권7호
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    • pp.1228-1236
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    • 2019
  • Recently, media platforms such as YouTube and Twitch provide services that can generate personal revenue by utilizing media content produced by individuals. In this regard, interest in the copyright of media content is increasing. In particular, in the case of an audio source, competition for securing audio source copyright is fierce because it is an essential element for almost all media content production. In this paper, we propose a method to store the audio source and its signature using a blockchain and distributed storage system to verify the copyright of music content. To identify the possibility of extracting the audio signature of the audio source and to include it as blockchain transaction data, we implement the audio source and its signature file upload system based on the proposed scheme. In addition, we show the effectiveness of the proposed method through experiments on uploading and retrieving audio files and identify future improvements.

SIMULATED IMPACTS TO NON-MAGNETIC CATACLYSMIC VARIABLE DISKS

  • MONTGOMERY, M.M.;HOWELL, N.;SCHWARZ, C.
    • 천문학논총
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    • 제30권2호
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    • pp.179-182
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    • 2015
  • Dust has recently been found to be prevalent in compact binaries such as non-magnetic Cataclysmic Variable systems. As a possible source of this dust is from solid bodies, we explore impacts to non-magnetic Cataclysmic Variable disks. We use three-dimensional Smoothed Particle Hydrodynamic simulations to search for impact signatures. From injections of whole bodies to these disks, we find pulse shapes in simulated bolometric light curves that resemble impact flashes in the light curves of the Shoemaker-Levy 9 event. As a result, we tentatively identify these light curve shapes as signatures of impacts.

불발 음원이 탄성파탐사 성능에 미치는 영향 (Effect of Different Misfired Source on Seismic Survey Quality)

  • 유해수;장재경;양승진
    • 한국음향학회지
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    • 제18권7호
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    • pp.75-79
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    • 1999
  • 다중채널 탄성파 음원배열에서 불발 음원에 따라 탐사 성능에 미치는 영향을 확인하기 위하여 음원배열의 빔 패턴과 원거리장 파형 변화를 비교 분석하였다. 원거리장 파형의 주신호 진폭은 전체 건 부피의 약 40%에 해당하는 음원들이 불발을 일으킬 경우, 탐사성능이 66% 정도 유지되는 것으로 확인되었다. 154㎐에서 같은 간격의 음원들이 불발 시에는 배열 형태와 관계없이 길이 및 폭 배열의 빔 폭이 동일하게 나타난다. 길이 배열의 빔 패턴에서는 불발된 음원의 부피가 증가됨에 따라 빔 폭이 41°에서 34°로 좁아지는 경향을 나타낸다. 따라서 부피가 작은 음원 배열일수록 빔폭이 좁고 양호한 파형이 생성되므로 작은 에너지가 요구되는 천부 지층탐사에 적합한 것으로 확인되었다.

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The Scanning Laser Source Technique for Detection of Surface-Breaking and Subsurface Defect

  • Sohn, Young-Hoon;Krishnaswamy, Sridhar
    • 비파괴검사학회지
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    • 제27권3호
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    • pp.246-254
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    • 2007
  • The scanning laser source (SLS) technique is a promising new laser ultrasonic tool for the detection of small surface-breaking defects. The SLS approach is based on monitoring the changes in laser-generated ultrasound as a laser source is scanned over a defect. Changes in amplitude and frequency content are observed for ultrasound generated by the laser over uniform and defective areas. The SLS technique uses a point or a short line-focused high-power laser beam which is swept across the test specimen surface and passes over surface-breaking or subsurface flaws. The ultrasonic signal that arrives at the Rayleigh wave speed is monitored as the SLS is scanned. It is found that the amplitude and frequency of the measured ultrasonic signal have specific variations when the laser source approaches, passes over and moves behind the defect. In this paper, the setup for SLS experiments with full B-scan capability is described and SLS signatures from small surface-breaking and subsurface flaws are discussed using a point or short line focused laser source.

결함 있는 안전성 증명을 갖는 수신자 지정 서명기법들에 대한 정확한 안전성분석 (Exact Security Analysis of Some Designated Verifier Signature Schemes With Defective Security Proof)

  • 김기태;양대헌;이경희
    • 정보보호학회논문지
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    • 제20권5호
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    • pp.37-48
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    • 2010
  • 수신자 지정 서명은 서명자가 지정된 검증자에게 서명의 유효성을 증명할 수 있도록 하는 서명기법이다. 한편 그 지정된 검증자는 제삼자에게 서명문서의 소스 즉 두 가능한 서명자들 중에서 누구에 의한 서명인지를 확인시킬 수 없다. 일반적인 전자서명과 달리, 수신자 지정 서명은 서명자가 지정된 수신자를 제외한 누구에게든 자신의 서명을 부인할 수도 있다. 그동안 제안된 몇몇 기법들 중에서, 최근 Zhang등의 기법과 Kang등의 기법이 다양한 공격에 취약하다는 사실이 밝혀졌다. 본 논문에서, 위의 기법들이 저자들에 의해서 안전성 증명이 제시되었음에도 불구하고 공격을 허용하게 되는 근본적인 이유를 밝히고, 더불어 Huang- Chou 기법과 Du-Wen 기법이 같은 문제를 갖는다는 사실을 보인다. 나아가 Huang-Chou의 기법에 대하여 실질적인 공격들을 제안한다. 마지막으로, Du-Wen 기법은 안전성 증명과정에서 저자들이 위 기법들의 저자들과 동일한 오류를 범하였으나 그 오류를 수정하여 실제 증명가능한 안전성을 갖는 기법임을 보인다.

Deep Packet Inspection Time-Aware Load Balancer on Many-Core Processors for Fast Intrusion Detection

  • Choi, Yoon-Ho;Park, Woojin;Choi, Seok-Hwan;Seo, Seung-Woo
    • IEIE Transactions on Smart Processing and Computing
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    • 제5권3호
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    • pp.169-177
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    • 2016
  • To realize high-speed intrusion detection by accommodating many regular expression (regex)-based signatures and growing network link capacities, we propose the Service TimE-Aware Load-balancing (STEAL) algorithm. This work is motivated from the observation that utilization of a many-core network intrusion detection system (NIDS) is influenced by unfair computational distribution among many-core NIDS nodes. To avoid such unfair computational distribution, STEAL is designed to dynamically distribute a large volume of traffic among many-core NIDS nodes based on packet service time, which is represented by the deep packet time in many-core NIDS nodes. From experiments, we show that compared to the commonly used load-balancing algorithm based on arrival rate, STEAL increases the number of received packets (i.e., decreases the number of dropped packets) in many-core NIDS. Specifically, by integrating an open source NIDS (i.e. Bro) with STEAL, we show that even under attack-dominant traffic and with many signatures, STEAL can rapidly improve the performance of many-core NIDS to realize high-speed intrusion detection.