• 제목/요약/키워드: overlapping

검색결과 1,956건 처리시간 0.027초

Study on the spectroscopic reconstruction of explosive-contaminated overlapping fingerprints using the laser-induced plasma emissions

  • Yang, Jun-Ho;Yoh, Jai-Ick
    • 분석과학
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    • 제33권2호
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    • pp.86-97
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    • 2020
  • Reconstruction and separation of explosive-contaminated overlapping fingerprints constitutes an analytical challenge of high significance in forensic sciences. Laser-induced breakdown spectroscopy (LIBS) allows real-time chemical mapping by detecting the light emissions from laser-induced plasma and can offer powerful means of fingerprint classification based on the chemical components of the sample. During recent years LIBS has been studied one of the spectroscopic techniques with larger capability for forensic sciences. However, despite of the great sensitivity, LIBS suffers from a limited detection due to difficulties in reconstruction of overlapping fingerprints. Here, the authors propose a simple, yet effective, method of using chemical mapping to separate and reconstruct the explosive-contaminated, overlapping fingerprints. A Q-switched Nd:YAG laser system (1064 nm), which allows the laser beam diameter and the area of the ablated crater to be controlled, was used to analyze the chemical compositions of eight samples of explosive-contaminated fingerprints (featuring two sample explosive and four individuals) via the LIBS. Then, the chemical validations were further performed by applying the Raman spectroscopy. The results were subjected to principal component and partial least-squares multivariate analyses, and showed the classification of contaminated fingerprints at higher than 91% accuracy. Robustness and sensitivity tests indicate that the novel method used here is effective for separating and reconstructing the overlapping fingerprints with explosive trace.

Multichannel Quantum Defect Theory Analysis of Overlapping Resonance Structures in Lu-Fano Plots of Rare Gas Spectra

  • Lee, Chun-Woo;Kong, Ja-Hyun
    • Bulletin of the Korean Chemical Society
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    • 제30권8호
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    • pp.1783-1792
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    • 2009
  • Although overlapping resonances have been studied extensively in conventional resonance theories, there have not been many studies on them in multichannel quantum defect theories (MQDT). In MQDT, overlapping resonances occur between the channels instead of states, which pose far greater difficulty. Their systematic treatment was obtained for cases involving degenerate closed channels by applying our previous theory, which decouples background scattering from the resonance scattering in the MQDT formulation. The use of mathematical theory on con-diagonalization and con-similarity was essential for handling the non-Hermitian symmetric complex matrix. Overlapping resonances in rare gas spectra of Ar, Kr and Xe were analyzed using this theory and the results were compared with the ones of the previous alternative parameterizations of MQDT which make the open-open part $K^{oo}$ and closed-closed part $K^{cc}$ of reactance submatrices zero. The comparison revealed that separation of background and resonance scatterings achieved in our formulation in a systematic way was not achieved in the representation of $K^{oo}\;=\;0\;and\;K^{cc}$ = 0 when overlapping resonances are present.

워터젯 절삭폭 중첩에 따른 암반제거 단면형상 분석 (Analysis of rock removal shape according to overlapping width of waterjet cutting)

  • 오태민;박동엽;박준식;조계춘
    • 한국터널지하공간학회 논문집
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    • 제23권3호
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    • pp.167-181
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    • 2021
  • 터널굴착의 경제성 확보 및 굴착 시 발생하는 진동저감을 위해 워터젯 시스템을 활용한 새로운 형태의 암반 굴착공법이 개발되고 있다. 워터젯 절삭을 이용한 효율적인 암반 굴착을 위해서는 워터젯 절삭폭의 중첩과정이 필수적이다. 본 연구는 초고압 연마재 워터젯 시스템을 이용하여 절삭폭 중첩도 및 이격거리에 따른 화강암 시편 절삭실험을 수행하였다. 실험결과를 바탕으로 중첩도 단계에 따른 화강암 절삭성능을 분석하였다. 그리고 형상인자를 절삭깊이, 절삭폭, 그리고 절삭부피로 분류하여 중첩 절삭 후 단면의 형상을 분석하였다. 절삭폭 중첩도가 58% 이하가 되면 중첩이 충분하지 않아 연속적인 암반제거가 불가능하였다. 반면 절삭폭 중첩도 67% 이상에서는 과절삭 현상이 확인되었다. 한편 부분중첩(25~75%) 조건에서는 기존 워터젯 절삭에 비해 효율적인 부피제거가 가능한 것으로 분석되었다. 해당 연구는 워터젯을 활용한 암반 굴착 시 최적 중첩도를 결정하기 위한 중요한 기초자료로 활용될 수 있을 것으로 기대된다.

Convolutionally-Coded and Spectrum-Overlapped Multicarrier DS-CDMA Systems in a Multipath Fading Channel

  • Oh, Jung-Hun;Kim, Ki-Doo;Milstein, Laurence B.
    • ETRI Journal
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    • 제23권4호
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    • pp.177-189
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    • 2001
  • Multicarrier DS-CDMA is an effective approach to combat fading and various kinds of interference. In this paper, we present an overlapped multicarrier DS-CDMA system, wherein each of the rate 1/M convolutionally-encoded symbols is also repetition coded and transmitted using overlapped multicarriers. However, since the frequency spectrums of successive carriers are allowed to overlap, the transmission bandwidth is more efficiently utilized. The effect of the overlapping percentage between successive carriers of a multicarrier DS-CDMA system on the performance is investigated to determine the overlapping percentage showing the best performance. We suggest two methods for sub-band overlapping variation. One is to allow variation of sub-band overlapping percentage when the total number of subcarriers is fixed. The other is to increase the number of sub-bands (the number of repetitions R) with fixed sub-band bandwidth. Given a total number of subcarriers MR, we show that the BER variation is highly dependent on the roll-off factor ${\beta}$ of a raised-cosine chip wave-shaping filter irrespective of convolutional encoding rate 1/M and repetition coding rate 1/R. We also analyze the possibility of reduction in total multi-user interference by considering the variation of both the roll-off factor ($0<{\beta}{\leq}1$) and the sub-band overlapping factor ($0<{\lambda}{\leq}2$), and show that the proposed system may outperform the multicarrier DS-CDMA system in [3].

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Viewpoint Invariant Person Re-Identification for Global Multi-Object Tracking with Non-Overlapping Cameras

  • Gwak, Jeonghwan;Park, Geunpyo;Jeon, Moongu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제11권4호
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    • pp.2075-2092
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    • 2017
  • Person re-identification is to match pedestrians observed from non-overlapping camera views. It has important applications in video surveillance such as person retrieval, person tracking, and activity analysis. However, it is a very challenging problem due to illumination, pose and viewpoint variations between non-overlapping camera views. In this work, we propose a viewpoint invariant method for matching pedestrian images using orientation of pedestrian. First, the proposed method divides a pedestrian image into patches and assigns angle to a patch using the orientation of the pedestrian under the assumption that a person body has the cylindrical shape. The difference between angles are then used to compute the similarity between patches. We applied the proposed method to real-time global multi-object tracking across multiple disjoint cameras with non-overlapping field of views. Re-identification algorithm makes global trajectories by connecting local trajectories obtained by different local trackers. The effectiveness of the viewpoint invariant method for person re-identification was validated on the VIPeR dataset. In addition, we demonstrated the effectiveness of the proposed approach for the inter-camera multiple object tracking on the MCT dataset with ground truth data for local tracking.

헤드업 디스플레이 휘도 증가를 위한 LED 합성비율과 영상잡음에 대한 연구 (A Synthesis Ratio of Light Emitting Diodes and Quantization Noise for Increasing Brightness of Head-up Displays)

  • 지용석
    • 방송공학회논문지
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    • 제21권5호
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    • pp.816-823
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    • 2016
  • 본 논문은 디스플레이 휘도를 증가시키기 위하여 적색, 녹색, 청색 고휘도 Light Emitting Diode(LED)를 광원으로 사용하고, Digital Micro Device(DMD) 패널을 적용한 헤드업 디스플레이에서 세 개의 LED 광원 합성 비율과 합성에 따른 양자화 노이즈를 최소화시키는 LED 합성 비율을 연구하였고, 밝기에 영향을 미치는 녹색 LED 구동 비율과 접합 온도에 대하여 분석하였다. 이를 통하여 39%의 LED 중첩 방법을 통하여 황색과 청록색의 2차원 색을 합성하여 33.3%의 휘도 증대 효과를 얻을 수 있었다. 또한 양자화노이즈를 억제하고 영상 화질 측면에서 우수한 색정밀도를 얻을 수 있었다.

정규 모집단의 평균 비교를 위한 신뢰구간 겹치기 시각화 (Visual inspection of overlapping confidence intervals for comparison of normal population means)

  • 최숙희;한경수
    • 응용통계연구
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    • 제30권5호
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    • pp.691-699
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    • 2017
  • 두 개의 정규 모집단의 평균이 같은가를 검증할 때 두 개의 신뢰구간이 겹치는 지를 시각적으로 판단하여 결정하는 방법은 매우 직관적이면서도 사용하기 쉽다. 그러나 신뢰구간이 겹칠 때도 두 집단의 평균은 통계적으로 유의하게 다를 수 있으므로 가설검증 결과와 다를 수 있다. 평균 차에 대한 신뢰구간을 각 평균의 신뢰구간으로 변환한 후에 두 신뢰구간이 겹치는지 여부를 시각적으로 판단하여 가설검증을 할 수 있는 방법을 제안한다. 또한 이 방법은 분산이 같은 k개의 정규 모집단의 평균을 비교할 경우에도 사용할 수 있음을 보인다.

A SPICE-Compatible Model for a Gate/Body-Tied PMOSFET Photodetector With an Overlapping Control Gate

  • Jo, Sung-Hyun;Bae, Myunghan;Choi, Byoung-Soo;Choi, Pyung;Shin, Jang-Kyoo
    • 센서학회지
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    • 제24권5호
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    • pp.353-357
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    • 2015
  • A new SPICE-compatible model for a gate/body-tied PMOSFET photodetector (GBT PD) with an overlapping control gate is presented. The proposed SPICE-compatible model of a GBT PD with an overlapping control gate makes it possible to control the photocurrent. Research into GBT PD modeling was proposed previously. However, the analysis and simulation of GBT PDs is not lacking. This SPICE model concurs with the measurement results, and it is simpler than previous models. The general GBT PD model is a hybrid device composed of a MOSFET, a lateral bipolar junction transistor (BJT), and a vertical BJT. Conventional SPICE models are based on complete depletion approximation, which is more applicable to reverse-biased p-n junctions; therefore, they are not appropriate for simulating circuits that are implemented with a GBT PD with an overlapping control gate. The GBT PD with an overlapping control gate can control the sensitivity of the photodetector. The proposed sensor is fabricated using a $0.35{\mu}m$ two-poly, four-metal standard complementary MOS (CMOS) process, and its characteristics are evaluated.

전차량의 능동 현가 장치 제어를 위한 중복 분산형 견실 고유구조지정 제어기 설계 (Overlapping Decentralized Robust EA Control Design for an Active Suspension System of a Full Car Model)

  • 정용하;최재원;김영호
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.217-217
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    • 2000
  • A decentralized robust EA(eigensoucture assignment) controller is designed for an active suspension system of a vehicle based on a full car model with 7-degree of freedom. Using overlapping decomposition, the full car model is decentralized by two half car models. For each half car model, a robust eigenstructure assignment controller can be obtained by using optimization approach. The performance of the decentralized robust EA controller is compared with that of a conventional centralized EA controller through computer simulations.

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THE LOWER BOUND OF THE NUMBER OF NON-OVERLAPPING TRIANGLES

  • Xu, Changqing;Ding, Ren
    • Journal of applied mathematics & informatics
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    • 제11권1_2호
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    • pp.283-290
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    • 2003
  • Andras Bezdek proved that if a convex n-gon and n points are given, then the points and the sides of the polygon can be renumbered so that at least[${\frac{n}{3}}$] triangles spanned by the ith point and the ith side (i = 1,2,...n) are mutually non-overlapping. In this paper, we show that at least [${\frac{n}{2}}$] mutually non-overlapping triangles can be constructed. This lower bound is best possible.