• Title/Summary/Keyword: Detection Key

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Efficient LDPC-Based, Threaded Layered Space-Time-Frequency System with Iterative Receiver

  • Hu, Junfeng;Zhang, Hailin;Yang, Yuan
    • ETRI Journal
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    • v.30 no.6
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    • pp.807-817
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    • 2008
  • We present a low-density parity-check (LDPC)-based, threaded layered space-time-frequency system with emphasis on the iterative receiver design. First, the unbiased minimum mean-squared-error iterative-tree-search (U-MMSE-ITS) detector, which is known to be one of the most efficient multi-input multi-output (MIMO) detectors available, is improved by augmentation of the partial-length paths and by the addition of one-bit complement sequences. Compared with the U-MMSE-ITS detector, the improved detector provides better detection performance with lower complexity. Furthermore, the improved detector is robust to arbitrary MIMO channels and to any antenna configurations. Second, based on the structure of the iterative receiver, we present a low-complexity belief-propagation (BP) decoding algorithm for LDPC-codes. This BP decoder not only has low computing complexity but also converges very fast (5 iterations is sufficient). With the efficient receiver employing the improved detector and the low-complexity BP decoder, the proposed system is a promising solution to high-data-rate transmission over selective-fading channels.

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A Countermeasure Against Fault Injection Attack on Block Cipher ARIA (블록 암호 ARIA에 대한 오류 주입 공격 대응 방안)

  • Kim, Hyung-Dong;Ha, Jae-Cheol
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.23 no.3
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    • pp.371-381
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    • 2013
  • An encryption algorithm is executed to supply data confidentiality using a secret key which is embedded in a crypto device. However, the fault injection attack has been developed to extract the secret key by injecting errors during the encryption processes. Especially, an attacker can find the secret key of block cipher ARIA using about 33 faulty outputs. In this paper, we proposed a countermeasure resistant to the these fault injection attacks by checking the difference value between input and output informations. Using computer simulation, we also verified that the proposed countermeasure has excellent fault detection rate and negligible computational overhead.

A New Rhodamine B-coumarin Fluorochrome for Colorimetric Recognition of Cu2+ and Fluorescent Recognition of Fe3+ in Aqueous Media

  • Tang, Lijun;Li, Fangfang;Liu, Minghui;Nandhakumar, Raju
    • Bulletin of the Korean Chemical Society
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    • v.32 no.9
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    • pp.3400-3404
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    • 2011
  • A new rhodamine B-coumarin conjugate (1) capable of recognizing both $Cu^{2+}$ and $Fe^{3+}$ using two different detection modes have been designed and synthesized. The metal ion induced optical changes of 1 were investigated in $CH_3CN-H_2O$ (1:1, v/v, HEPES 50 mM, pH = 7.0) solution. Sensor 1 exhibits selective colorimetric recognition of $Cu^{2+}$ and fluorescent recognition of $Fe^{3+}$ with UV-vis and fluorescence spectroscopy, respectively. Moreover, both of the $Cu^{2+}$ and $Fe^{3+}$ recognition processes are observed to be barely interfered by other coexisting metal ions.

Malware Containment Using Weight based on Incremental PageRank in Dynamic Social Networks

  • Kong, Jong-Hwan;Han, Myung-Mook
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.1
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    • pp.421-433
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    • 2015
  • Recently, there have been fast-growing social network services based on the Internet environment and web technology development, the prevalence of smartphones, etc. Social networks also allow the users to convey the information and news so that they have a great influence on the public opinion formed by social interaction among users as well as the spread of information. On the other hand, these social networks also serve as perfect environments for rampant malware. Malware is rapidly being spread because relationships are formed on trust among the users. In this paper, an effective patch strategy is proposed to deal with malicious worms based on social networks. A graph is formed to analyze the structure of a social network, and subgroups are formed in the graph for the distributed patch strategy. The weighted directions and activities between the nodes are taken into account to select reliable key nodes from the generated subgroups, and the Incremental PageRanking algorithm reflecting dynamic social network features (addition/deletion of users and links) is used for deriving the high influential key nodes. With the patch based on the derived key nodes, the proposed method can prevent worms from spreading over social networks.

Adaptive Selective Compressive Sensing based Signal Acquisition Oriented toward Strong Signal Noise Scene

  • Wen, Fangqing;Zhang, Gong;Ben, De
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.9
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    • pp.3559-3571
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    • 2015
  • This paper addresses the problem of signal acquisition with a sparse representation in a given orthonormal basis using fewer noisy measurements. The authors formulate the problem statement for randomly measuring with strong signal noise. The impact of white Gaussian signals noise on the recovery performance is analyzed to provide a theoretical basis for the reasonable design of the measurement matrix. With the idea that the measurement matrix can be adapted for noise suppression in the adaptive CS system, an adapted selective compressive sensing (ASCS) scheme is proposed whose measurement matrix can be updated according to the noise information fed back by the processing center. In terms of objective recovery quality, failure rate and mean-square error (MSE), a comparison is made with some nonadaptive methods and existing CS measurement approaches. Extensive numerical experiments show that the proposed scheme has better noise suppression performance and improves the support recovery of sparse signal. The proposed scheme should have a great potential and bright prospect of broadband signals such as biological signal measurement and radar signal detection.

Chemiluminescence Determination of Balofloxacin Based on Europium (III)-Sensitized KBrO3-Na2S2O4 Reaction in Micellar Medium

  • Zhao, Fang;Qi, Yu;Xiong, Wei
    • Bulletin of the Korean Chemical Society
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    • v.33 no.1
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    • pp.204-208
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    • 2012
  • A novel chemiluminescence (CL) flow injection method for the determination of balofloxacin is described. The method is based on the weak CL signal arising from the reaction of $KBrO_3$ with $Na_2S_2O_4$ in acidic medium being significantly enhanced by balofloxacin in the presence of europium (III) ion and sodium dodecyl benzene sulfonate (SDBS). The experimental conditions that affected CL intensity were carefully optimized and the CL reaction mechanism was briefly discussed. Under the optimum conditions, the relative CL intensity was proportional to the concentration of balofloxacin in the range of $7.0{\times}10^{-11}$ to $3.0{\times}10^{-7}g\;mL^{-1}$. The detection limit was $2.7{\times}10^{-11}g\;mL^{-1}$ and the relative standard deviation was 2.1% for $7.0{\times}10^{-10}g\;mL^{-1}$ balofloxacin (n = 13). The proposed method was successfully applied to the determination of balofloxacin in pharmaceutical formulations and biological fluids.

Electrochemistry and Determination of 1-Naphthylacetic Acid Using an Acetylene Black Film Modified Electrode

  • Huang, Wensheng;Qu, Wanyun;Zhu, Dazhai
    • Bulletin of the Korean Chemical Society
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    • v.29 no.7
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    • pp.1323-1325
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    • 2008
  • The acetylene black (AB) was dispersed into water in the presence of dihexadecyl hydrogen phosphate (DHP) via ultrasonication, resulting in a stable and well-distributed AB/DHP suspension. After evaporation of water, an AB/DHP composite film-modified electrode was prepared. The electrochemical responses of $K_3$[Fe$(CN)_6$] at the unmodified electrode, DHP film-modified electrode and AB/DHP film-modified electrode were investigated. It is found that the AB/DHP film-modified electrode possesses larger surface area and electron transfer rate constant. Furthermore, the electrochemical behaviors of 1-naphthylacetic acid (NAA) were examined. At the AB/DHP film-modified electrode, the oxidation peak current of NAA remarkably increases. Based on this, a sensitive and convenient electrochemical method was proposed for the determination of NAA. The linear range is in the range from $4.0 {\times} 10^{-8}\;to\;5.0 {\times} 10^{-6}$ mol $L^{-1}$, and the detection limit is $1.0 {\times} 10^{-8}$ mol $L^{-1}$. Finally, this new sensing method was employed to determine NAA in several soil samples.

A New Rhodamine B Hydrazide Hydrazone Derivative for Colorimetric and Fluorescent "Off-On" Recognition of Copper(II) in Aqueous Media

  • Tang, Lijun;Guo, Jiaojiao;Wang, Nannan
    • Bulletin of the Korean Chemical Society
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    • v.34 no.1
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    • pp.159-163
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    • 2013
  • A new Rhodamine B hydrazide hydrazone 1 has been synthesized and investigated as a colorimetric and fluorescent "off-on" sensor for the recognition of $Cu^{2+}$ in $CH_3CN/H_2O$ (1:1, v/v, HEPES 10 mM, pH = 7.0) solution. Sensor 1 displayed highly selective, sensitive and rapid recognition behavior toward $Cu^{2+}$ among a range of biologically and environmentally important metal ions. Sensor 1 bind $Cu^{2+}$ via a 1:1 stoichiometry with an association constant of $1.92{\times}10^6\;M^{-1}$, and the detection limit is evaluated to be $7.96{\times}10^{-8}\;M$. The $Cu^{2+}$ recognition event is reversible and is barely interfered by other coexisting metal ions.

Deep Learning based Loss Recovery Mechanism for Video Streaming over Mobile Information-Centric Network

  • Han, Longzhe;Maksymyuk, Taras;Bao, Xuecai;Zhao, Jia;Liu, Yan
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.9
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    • pp.4572-4586
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    • 2019
  • Mobile Edge Computing (MEC) and Information-Centric Networking (ICN) are essential network architectures for the future Internet. The advantages of MEC and ICN such as computation and storage capabilities at the edge of the network, in-network caching and named-data communication paradigm can greatly improve the quality of video streaming applications. However, the packet loss in wireless network environments still affects the video streaming performance and the existing loss recovery approaches in ICN does not exploit the capabilities of MEC. This paper proposes a Deep Learning based Loss Recovery Mechanism (DL-LRM) for video streaming over MEC based ICN. Different with existing approaches, the Forward Error Correction (FEC) packets are generated at the edge of the network, which dramatically reduces the workload of core network and backhaul. By monitoring network states, our proposed DL-LRM controls the FEC request rate by deep reinforcement learning algorithm. Considering the characteristics of video streaming and MEC, in this paper we develop content caching detection and fast retransmission algorithm to effectively utilize resources of MEC. Experimental results demonstrate that the DL-LRM is able to adaptively adjust and control the FEC request rate and achieve better video quality than the existing approaches.

A Combined QRS-complex and P-wave Detection in ECG Signal for Ubiquitous Healthcare System

  • Bhardwaj, Sachin;Lee, Dae-Seok;Chung, Wan-Young
    • Journal of information and communication convergence engineering
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    • v.5 no.2
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    • pp.98-103
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    • 2007
  • Long term Electrocardiogram (ECG) [1] analysis plays a key role in heart disease analysis. A combined detection of QRS-complex and P-wave in ECG signal for ubiquitous healthcare system was designed and implemented which can be used as an advanced warning device. The ECG features are used to detect life-threating arrhythmias, with an emphasis on the software for analyzing QRS complex and P-wave in wireless ECG signals at server after receiving data from base station. Based on abnormal ECG activity, the server will transfer alarm conditions to a doctor's Personal Digital Assistant (PDA). Doctor can diagnose the patients who have survived from cardiac arrhythmia diseases.