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A secure double spectrum auction scheme

Digital communications and Networks 2024年第5期10卷 1415-1427页

作者： Jiaqi Wang Ning Lu Ziyang Gong Wenbo Shi Chang Choi School of computer Science and engineering Northeastern University School of computer Science and Technology Xidian University dept.of computer engineering Gachon University School of computer and Communication engineering Northeastern University

With the arrival of the 5G era,wireless communication technologies and services are rapidly exhausting the limited spectrum *** auctions came into being,which can effectively utilize spectrum *** of the complexity of the electronic spectrum auction network environment,the security of spectrum auction can not be *** scholars focus on researching the security of the single-sided auctions,while ignoring the practical scenario of a secure double spectrum auction where participants are composed of multiple sellers and *** begin to design the secure double spectrum auction mechanisms,in which two semi-honest agents are introduced to finish the spectrum auction *** these two agents may collude with each other or be bribed by buyers and sellers,which may create security risks,therefore,a secure double spectrum auction is proposed in this *** traditional secure double spectrum auctions,the spectrum auction server with Software Guard Extensions(SGX) component is used in this paper,which is an Ethereum blockchain platform that performs spectrum auctions.A secure double spectrum protocol is also designed,using SGX technology and cryptographic tools such as Paillier cryptosystem,stealth address technology and one-time ring signatures to well protect the private information of spectrum *** addition,the smart contracts provided by the Ethereum blockchain platform are executed to assist offline verification,and to verify important spectrum auction information to ensure the fairness and impartiality of spectrum ***,security analysis and performance evaluation of our protocol are discussed.

关键词： Secure double spectrum auction SGX technology Privacy information Ethereum platform Verification

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Effect of pulsed current cathodic protection on pipeline steel API 5L X65 corrosion mitigation: An investigation and machine learning-assisted modeling

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Corrosion communications 2023年第4期12卷 29-45页

作者： Hosein Eslamian Mehdi Javidi Mohammad Reza Zamani Mohammad Mahdi Dana Eghbal Mansoori Department of Materials Science and engineering School of Engineering Shiraz University School of Metallurgy and Materials engineering College of Engineering University of Tehran computer Science Eng.and IT Dept. School of Electrical and Computer Engineering Shiraz University

Pulsed current cathodic protection(PCCP) could be more effective than direct current cathodic protection(DCCP)for mitigating corrosion in buried structures in the oil and gas industries if appropriate pulsed parameters are chosen. The purpose of this research is to present the corrosion prevention mechanism of the PCCP technique by taking into account the effects of duty cycle as well as frequency, modeling the relationships between pulse parameters(frequency and duty cycle) and system outputs(corrosion rate, protective current and pipe-to-soil potential) and finally identifying the most effective protection conditions over a wide range of frequency(2–10 kHz) and duty cycle(25%-75%). For this, pipe-to-soil potential, pH, current and power consumption, corrosion rate, surface deposits and investigation of pitting corrosion were taken into account. To model the input-output relationship in the PCCP method, a data-driven machine learning approach was used by training an artificial neural network(ANN). The results revealed that the PCCP system could yield the best protection conditions at 10 kHz frequency and 50% duty cycle, resulting in the longest protection length with the lowest corrosion rate at a consumption current 0.3 time that of the DCCP method. In the frequency range of 6–10 kHz and duty cycles of 50%-75%, SEM images indicated a uniform distribution of calcite deposits and no pits on cathode surface.

关键词： Pulsed current cathodic protection Duty cycle Frequency Artificial neural network API X65 pipeline steel

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Two-stage image segmentation based on edge and region information

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Journal of Harbin Institute of Technology(New Series) 2007年第4期14卷 533-540页

作者：冉鑫戚飞虎 Merchant Marine College Shanghai Maritime University dept. of computer Science and engineering Shanghai Jiaotong University

A two-stage method for image segmentation based on edge and region information is proposed. Different deformation schemes are used at two stages for segmenting the object correctly in image plane. At the first stage, the contour of the model is divided into several segments hierarchically that deform respectively using affine transformation. After the contour is deformed to the approximate boundary of object, a fine match mechanism using statistical information of local region to redefine the external energy of the model is used to make the contour fit the object's boundary exactly. The algorithm is effective, as the hierarchical segmental deformation makes use of the globe and local information of the image, the affine transformation keeps the consistency of the model, and the reformative approaches of computing the internal energy and external energy are proposed to reduce the algorithm complexity. The adaptive method of defining the search area at the second stage makes the model converge quickly. The experimental results indicate that the proposed model is effective and robust to local minima and able to search for concave objects.

关键词： active contour model region growing image segmentation affine transformation

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Achievable degrees of freedom of MIMO two-way X relay channel with delayed CSIT

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Science China(Information Sciences) 2016年第8期59卷 193-203页

作者： Qingyun LI Gang WU Hongxiang LI Shaoqian LI National Key Laboratory of Science and Technology on communications University of Electronic Science and Technology of China Department of Electrical and computer engineering University of Louisville

The previous work on interference alignment for multiple-input-multiple-output(MIMO) two-way X relay channel assumes perfect channel state information at the transmitter(CSIT), which is reasonable in slow fading channel. However, in fast fading scenario, this assumption is impractical. In this paper, assuming that each node has delayed CSIT, we study the achievable degrees of freedom(DOF) for MIMO two-way X relay channel in frequency division duplex(FDD) systems. Specifically, in the broadcast(BC) phase, we propose a new multiple-stage transmission(MST) scheme, which utilizes retrospective interference alignment for physical layer network coding(PLNC). We show that MST can achieve significant DOF gain and tremendous power gain over other schemes. When the number of antennas for each user, N, is smaller than the number of the relays, M, the time division multiple access(TDMA) scheme can only achieve an ergodic sum-rate increase by N bps/Hz for every increasing of 3 d B of signal-to-noise power ratio(SNR), while the proposed MST scheme can achieve an ergodic sum-rate increase by M bps/Hz.

关键词： degrees of freedom physical layer network coding interference alignment delayed CSIT multiplestage transmission

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Orthogonal Stacked Spectral Coding Labels for Fast Packets Routing over Optical MPLS Network

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Journal of Electronic Science and Technology 2015年第2期13卷 130-134页

作者： Kai-Sheng Chen Chao-Chin Yang Jen-Fa Huang Institute of computer and communications Department of Electrical EngineeringNational Chen-Kung University Department of Electro-Optical engineering Kun Shan University

Multi-protocol label switching（MPLS） has the advantage of high efficiency in the second layer, which improves the performance of data packets routing. In this paper, a new structure to implement optical MPLS is proposed. We construct a code family for spectral-amplitude coding（SAC） labels in the optical MPLS networks. SAC labels are suitable for optical packet switching because they can be constructed and recognized quickly at each router. We use the label stacking to provide hierarchical routing to avoid swapping labels at each forwarding node and reduce system complexity. However, the phase-induced intensity noise（PIIN） appears due to the incoherent property of the light source when the stacked labels set makes the correlation decoding with the local node label,which degrades system performance.

关键词： label hierarchical switching quickly routing decoding forwarding packet matches router

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Variable TDMA MAC Protocol For WDM EPON

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光学学报 2003年第S1期23卷 777-778页

作者： Minsuk Jung Yongseok Chang Jonghoon Eom Sungho Kim dept. of computer engineering Kyungpook National University Daegu KoreaDept. of Computer Engineering Kyungpook National University Daegu KoreaTelecommunication Network Laboratory Korea Telecom Jeonmin-dong Yusung-gu Daejeon KoreaDept. of Computer Engineering Kyungpook National University Daegu Korea

A MAC(Media Access Control) protocol, one of the most important technologies for an EPON(Ethernet Passive Optical Network), contains a scheduling algorithm to avoid collisions in shared links and assigns an effective bandwidth when ONUs (Optical Network Units) transfer signals upward. The current paper proposes a MAC Protocol that operates a TDMA(Time method with a variable slot assignment to overcome short of bandwidth using by the number of n wavelength., the next generation access network. To verify ...

关键词： Variable TDMA MAC Protocol For WDM EPON for OPNET MAC TDMA

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Bandwidth Allocation Method by Service for WDM EPON

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光学学报 2003年第S1期23卷 775-776页

作者： Yongseok Chang Changgyu Choi Jonghoon Eom Sungho Kim dept. of computer engineering Kyungpook National University Daegu KoreaDept. of Computer Engineering Kyungpook National University Daegu KoreaTelecommunication Network Laboratory Korea Telecom Jeonmin-dong Yusung-gu Daejeon KoreaDept. of Computer Engineering Kyungpook National University Daegu Korea

A WDM(Wavelength Division Multiplexing) EPON(Ethernet Passive Optical Network) is an economical and efficient access network that has attracted significant research attention in recent years. A MAC(Media Access Control) Protocol of PON is based on TDMA(Time Division Multiple Access) basically, we can classify this protocol into a fixed length slot assignment method suitable for leased line supporting Qos(Quality of Service) and a variable length slot assignment method suitable for LAN/MAN with the best ...

关键词： WDM on Bandwidth Allocation Method by Service for WDM EPON ONU by for

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Compressive Sensing Approach in Multicarrier Sparsely Indexing Modulation Systems

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China communications 2017年第11期14卷 151-166页

作者： Mostafa Salah Osama A.Omer Usama S.Mohamed dept. of Electrical engineering Sohag University Sohag Egypt dept. of Electrical engineering Aswan University Aswan 81542 Egypt dept. of Electrical engineering Assiut University Assiut Egypt dept. of Electronics & Comm. engineering Arab Academy for Science Technology and Maritime Transport Aswan

recently the indexed modulation(IM) technique in conjunction with the multi-carrier modulation gains an increasing attention. It conveys additional information on the subcarrier indices by activating specific subcarriers in the frequency domain besides the conventional amplitude-phase modulation of the activated subcarriers. Orthogonal frequency division multiplexing(OFDM) with IM(OFDM-IM) is deeply compared with the classical OFDM. It leads to an attractive trade-off between the spectral efficiency(SE) and the energy efficiency(EE). In this paper, the concept of the combinatorial modulation is introduced from a new point of view. The sparsity mapping is suggested intentionally to enable the compressive sensing(CS) concept in the data recovery process to provide further performance and EE enhancement without SE loss. Generating artificial data sparsity in the frequency domain along with naturally embedded channel sparsity in the time domain allows joint data recovery and channel estimation in a double sparsity framework. Based on simulation results, the performance of the proposed approach agrees with the predicted CS superiority even under low signal-to-noise ratio without channel coding. Moreover, the proposed sparsely indexed modulation system outperforms the conventional OFDM system and the OFDM-IM system in terms of error performance, peak-to-average power ratio(PAPR) and energy efficiency under the same spectral efficiency.

关键词： indexed modulation combinatorial modulation double sparsity critical sparsity sparsely indexed modulation OFDM-IM

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Offline Arabic character recognition system

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Journal of Harbin Institute of Technology(New Series) 2003年第1期10卷 80-88页

作者：黄建华唐降龙 dept. of computer Science Harbin Institute of Technology

Several languages use the Arabic alphabets and Arabic scripts present challenges because the letter shape is context sensitive. For the past three decades, there has been a mounting interest among researchers in this problem. In this paper we present an Arabic Character Recognition system and review the theory behind the Arabic recognition system, the characteristics of Arabic writing, the sequence steps of recognizing Arabic text. These steps are separately discussed, and previous research work on each step is reviewed. Also in this paper we give some samples of Arabic fonts.

关键词： recognition off line Arabic character

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Buffer management optimization strategy for satellite ATM

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Journal of Systems engineering and Electronics 2006年第1期17卷 19-23页

作者： Lu Rang Cao Zhigang State Key Laboratory on Microwave and Digital communications Dept. of Electronics Engineering Tsinghua Univ. Beijing 100084 P. R. China

ECFD （erroneous cell tail drop）, a buffer management optimization strategy is suggested which can improve the utilization of buffer resources in satellite ATM （asynchronous transfer mode） networks. The strategy, in which erroneous cells caused by satellite channel and the following cells that belong to the same PDU （protocol data Unit） are discarded, concerns non-real-time data services that use higher layer protocol for retransmission. Based on EPD （early packet drop） policy, mathematical models are established with and without ECTD. The numerical results show that ECTD would optimize buffer management and improve effective throughput （goodput）, and the increment of goodput is relative to the CER （cell error ratio） and the PDU length. The higher their values are, the greater the increment. For example, when the average PDU length values are 30 and 90, the improvement of goodput are respectively about 4% and 10%.

关键词： asynchronous transfer mode satellite ATM buffer management early packet drop erroneous cell tail drop.

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