• Title/Summary/Keyword: Detection scheme

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Pulsed Amperometric Detection of Metal Ions Complexing with EDTA in a Flow Injection System

  • 이준우;여인형;편종홍
    • Bulletin of the Korean Chemical Society
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    • v.18 no.3
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    • pp.316-318
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    • 1997
  • A general and universal detection method, which can be used in high performance liquid chromatography (HPLC) and flow injection analysis (FIA) system for the determination of any metal ions complexing with ethylenediaminetetraacetic acid (EDTA), is demonstrated. Pulsed amperometric detection scheme is applied in a flow-through thin layer electrochemical cell at an Au working electrode. Fluctuation of peak current level at the same flow rate of carrier solution is minimized at this solid working electrode, whereas not at a dropping mercury electrode. Removal of dissolved oxygen can be omitted with this detection method, which is a required step for cathodic detection methods. Also, a group of metal ions can be determined selectively and indirectly with this detection scheme.

Estimation of State-of-charge and Sensor Fault Detection of a Lithium-ion Battery in Electric Vehicles (전기자동차용 리튬이온전지를 위한 SOC 추정 및 센서 고장검출)

  • Han, Man-You;Lee, Kee-Sang
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.63 no.8
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    • pp.1085-1091
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    • 2014
  • A model based SOC estimation scheme using parameter identification is described and applied to a Lithium-ion battery module that can be installed in electric vehicles. Simulation studies are performed to verify the effect of sensor faults on the SOC estimation results for terminal voltage sensor and load current sensor. The sensor faults should be detected and isolated as soon as possible because the SOC estimation error due to any sensor fault seriously affects the overall performance of the BMS. A new fault detection and isolation(FDI) scheme by which the fault of terminal voltage sensor and load current sensor can be detected and isolated is proposed to improve the reliability of the BMS. The proposed FDI scheme utilizes the parameter estimation of an input-output model and two fuzzy predictors for residual generation; one for terminal voltage and the other for load current. Recently developed dual polarization(DP) model is taken to develope and evaluate the performance of the proposed FDI scheme. Simulation results show the practical feasibility of the proposed FDI scheme.

A High-Quality Image Authentication Scheme for AMBTC-compressed Images

  • Lin, Chia-Chen;Huang, Yuehong;Tai, Wei-Liang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.12
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    • pp.4588-4603
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    • 2014
  • In this paper, we present a high-quality image authentication scheme based on absolute moment block truncation coding. In the proposed scheme, we use the parity of the bitmap (BM) to generate the authentication code for each compressed image block. Data hiding is used to authenticate whether the content has been altered or not. For image authentication, we embed the authentication code to quantization levels of each image block compressed by absolute moment block truncation coding (AMBTC) which will be altered when the host image is manipulated. The embedding position is generated by a pseudo-random number generator for security concerned. Besides, to improve the detection ability we use a hierarchical structure to ensure the accuracy of tamper localization. A watermarked image can be precisely inspected whether it has been tampered intentionally or incautiously by checking the extracted watermark. Experimental results demonstrated that the proposed scheme achieved high-quality embedded images and good detection accuracy, with stable performance and high expansibility. Performance comparisons with other block-based data hiding schemes are provided to demonstrate the superiority of the proposed scheme.

A Rule Protecting Scheme with Symmetric Cryptosystem for Intrusion Detection System (암호화 기법을 적용한 침입 탐지 시스템의 룰 보호 기법)

  • Son Hyung-Seo;Kim Hyun-Sung;Bu Ki-Dong
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.14 no.6
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    • pp.3-13
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    • 2004
  • Kvarnstrom et al. ${in}^{[10]}$ proposed a rule protection scheme by using one-way hash function to protect rules in security systems over ubiquitous environment. Son et at. ${in}^{[5-6]}$ also prooposed a rule protection scheme for Snort, which is one of the most common IDS. These schemes provide security only for the header information but not for its contents. To solve this problem, this paper presents a scheme based on the symmetric cryptosystem over Snort not only for the header information but also contents. This paper uses the key management based on PCMCIA security module proposed ${by}^{[12]}$ for the symmetric cryptosystem. Our scheme could be adjusted to other security systems, which use the rule based detection.

Low Complexity LSD Scheme for Joint Iterative MIMO Detection (반복 MIMO 검출을 위한 저 복잡도 LSD 기법)

  • Ahmed, Saleem;Kim, Sooyoung
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38C no.11
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    • pp.1051-1059
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    • 2013
  • This paper proposes a complexity reduced list sphere decoding (LSD) scheme for joint iterative soft detection scheme for coded MIMO system. The conventional LSD scheme is based on searching the candidates with a fixed radius. However, once the candidate list is full, it is highly probable that the radius can be reduced. By reducing the radius, the complexity can be also reduced. We propose a simple and efficient radius update method for complexity reduction of list version sphere decoding and its application to iterative soft MIMO detection. We evaluate the performance of the proposed scheme with a joint soft-input-soft-ouput iterative MIMO detection in combination with turbo codes. Simulation results show that the proposed methods provide substantial complexity reduction while achieving similar bit error rate (BER) performance as the conventional LSD scheme.

Performance Analysis for SVR-MMSE Detection of Constant Modulus Signals in MIMO-OFDM Systems (MIMO-OFDM 시스템에서 Constant Modulus 신호의 SVR-MMSE 검출 성능 분석)

  • Shin, Chul-Min;Seo, Myoung-Seok;Yang, Qing-Hai;Kwak, Kyung-Sup
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.12A
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    • pp.1198-1204
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    • 2006
  • In this paper, we extend SVR-MMSE detection scheme which is proposed in MIMO system to MIMO-OFDM system, and evaluate performance of the system in frequency selective fading channel. First of all, we explain about typical MIMO-OFDM system and detection scheme of constant modulus signals in this system. And compare proposed SVR-MMSE with Zero Forcing, Minimum Mean Square Error which is conventional detection scheme. we identify that the performance of the proposed system is shown different by varying doppler frequency in frequency selective fading channel using jakes channel model. The result of detection performance by the proposed SVR-MMSE in this simulation, it shows that proposed algorithm have a good performance in MIMO-OFDM systems.

Implementation-Friendly QRM-MLD Using Trellis-Structure Based on Viterbi Algorithm

  • Choi, Sang-Ho;Heo, Jun;Ko, Young-Chai
    • Journal of Communications and Networks
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    • v.11 no.1
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    • pp.20-25
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    • 2009
  • The maximum likelihood detection with QR decomposition and M-algorithm (QRM-MLD) has been presented as a suboptimum multiple-input multiple-output (MIMO) detection scheme which can provide almost the same performance as the optimum maximum likelihood (ML) MIMO detection scheme but with the reduced complexity. However, due to the lack of parallelism and the regularity in the decoding structure, the conventional QRM-MLD which uses the tree-structure still has very high complexity for the very large scale integration (VLSI) implementation. In this paper, we modify the tree-structure of conventional QRM-MLD into trellis-structure in order to obtain high operational parallelism and regularity and then apply the Viterbi algorithm to the QRM-MLD to ease the burden of the VLSI implementation.We show from our selected numerical examples that, by using the QRM-MLD with our proposed trellis-structure, we can reduce the complexity significantly compared to the tree-structure based QRM-MLD while the performance degradation of our proposed scheme is negligible.

A Study on Partial Correlation based PSS Detection Schemes for Initial Cell Search in LTE Systems (LTE 시스템에서 초기 셀 탐색을 위한 부분 상관값 기반 PSS 검출 방식에 관한 고찰)

  • Joo, Jung Suk
    • Journal of the Institute of Electronics and Information Engineers
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    • v.51 no.9
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    • pp.3-10
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    • 2014
  • The synchronization signal in Long Term Evolution (LTE) systems contains the primary synchronization signal (PSS) and the secondary synchronization signal (SSS), and the overall synchronization performance is dominated by PSS detection. In this paper, we propose a PSS detection scheme employing three partial correlation based PSS detectors with different partial correlation lengths, in which calculated partial correlation values are reused in order to reduce computational complexity. A coherent selection scheme using tentative frequency offsets is also proposed to select one reliable result from outputs of partial correlation based PSS detectors. It is shown through computer simulation that the proposed scheme can have a robust detection performance in wide range of frequency offsets.

ML Symbol Detection for MIMO Systems in the Presence of Channel Estimation Errors

  • Yoo, Namsik;Back, Jong-Hyen;Choi, Hyeon-Yeong;Lee, Kyungchun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.11
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    • pp.5305-5321
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    • 2016
  • In wireless communication, the multiple-input multiple-output (MIMO) system is a well-known approach to improve the reliability as well as the data rate. In MIMO systems, channel state information (CSI) is typically required at the receiver to detect transmitted signals; however, in practical systems, the CSI is imperfect and contains errors, which affect the overall system performance. In this paper, we propose a novel maximum likelihood (ML) scheme for MIMO systems that is robust to the CSI errors. We apply an optimization method to estimate an instantaneous covariance matrix of the CSI errors in order to improve the detection performance. Furthermore, we propose the employment of the list sphere decoding (LSD) scheme to reduce the computational complexity, which is capable of efficiently finding a reduced set of the candidate symbol vectors for the computation of the covariance matrix of the CSI errors. An iterative detection scheme is also proposed to further improve the detection performance.

Lattice-Reduction-Aided Detection based Extended Noise Variance Matrix using Semidefinite Relaxation in MIMO Systems (MIMO시스템에서 Semidefinite Relaxation을 이용한 잡음 분산 행렬 기반의 Lattice-Reduction-Aided 검출기)

  • Lee, Dong-Jin;Park, Su-Bin;Byun, Youn-Shik
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.11C
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    • pp.932-939
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    • 2008
  • Recently lattice-reduction (LR) has been used in signal detection for multiple-input multiple-output (MIMO) systems. The conventional LR aided detection schemes are combinations of LR and signal detection methods such as zero-forcing (ZF) and minimum mean square error (MMSE) detection. In this paper, we propose the Lattice-Reduction-aided scheme based on extended noise variance matrix to search good candidate symbol set in quantization step. Then this scheme estimates transmitted symbol with Semidefinite Relaxation by candidate symbol set. Simulation results in a random MIMO system show that the proposed scheme exhibits improved performance and a slight increase in complexity.