共查询到20条相似文献,搜索用时 755 毫秒
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WANG Jian ZHANG Quan TANG Chao-jing 《光电子快报》2006,2(3):209-212
Quantum cryptography combines quantum theorywithclassical cryptography,which provides uncondition-ally secure information exchange by using quantumeffects .Many advances have been made in quantumcryptography in recent years ,including quantum keydistribut… 相似文献
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Shin-Lun Tung Yau-Tarng Juang 《Electronics letters》1996,32(17):1542-1543
A new scheme is proposed that compensates for the effects of noise in speech recognition systems. The new scheme was applied to Mandarin speech recognition. Another scheme, based on interpolation of the compensation vectors of several environments for a particular environment that is not obtained during the training phase, called interpolated SSDCN (ISSDCN), is also presented. Experimental results show that the scheme performs well under different SNR conditions 相似文献
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Fully homomorphic encryption is faced with two problems now.One is candidate fully homomorphic encryption schemes are few.Another is that the efficiency of fully homomorphic encryption is a big question.In this paper,we propose a fully homomorphic encryption scheme based on LWE,which has better key size.Our main contributions are:(1) According to the binary-LWE recently,we choose secret key from binary set and modify the basic encryption scheme proposed in Linder and Peikert in 2010.We propose a fully homomorphic encryption scheme based on the new basic encryption scheme.We analyze the correctness and give the proof of the security of our scheme.The public key,evaluation keys and tensored ciphertext have better size in our scheme.(2) Estimating parameters for fully homomorphic encryption scheme is an important work.We estimate the concert parameters for our scheme.We compare these parameters between our scheme and Bra 12 scheme.Our scheme have public key and private key that smaller by a factor of about logq than in Bra12 scheme.Tensored ciphertext in our scheme is smaller by a factor of about log2 q than in Bra 12 scheme.Key switching matrix in our scheme is smaller by a factor of about log3 q than in Bra 12 scheme. 相似文献
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文章提出了一种精简指令集8位单片机中,算术逻辑单元的工作原理。在此基础上,对比传统PIC方案、以及在ALU内部再次采用流水线作业的332方案、44方案,并用Synopsys综合工具实现了它们。综合及仿真结果表明。根据该单片机系统要求,44方案速度最高,比332方案可提高43.9%,而面积仅比最小的332方案增加1.6%。在分析性能差异的根本原因之后,阐明了该方案的优越性。 相似文献
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An investigation is conducted of two acknowledgment schemes for sliding window flow control in packet communications: the delayed acknowledgment (D-ACK) scheme and the window acknowledgment (W-ACK) scheme. It is shown that the acknowledgment scheme of the link layer of the X.25 protocol can be modeled by the D-ACK scheme and that of the packet layer by the W-ACK scheme. The efficiencies of these acknowledgment schemes are shown by the mean number of acknowledgment control frames generated for the transmission of a single information frame, the transmission blocking probability, and the mean transmission time of data frames. Numerical and simulation results showing that the D-ACK scheme with an appropriately selected value of predetermined waiting time is better than the W-ACK scheme are presented 相似文献
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A new scheme of synchronous CDMA is introduced in the paper. The new scheme is based on a code made by all the cyclical translations of a basic sequence having constant amplitude and white discrete spectrum. Such a code is proposed here for the first time as a code for CDMA. According to the proposed scheme, a cyclic prefix is appended to the multiplexed signal. The proposed scheme has a property that none of the known CDMA schemes has: in a multipath environment, it allows multiuser interference to become cyclic intersymbol interference. Noticeably, the memory of the finite state machine that describes the ISI model is equal to memory of the multipath channel. The main advantage of our proposed scheme is that optimal and suboptimal detectors can be obtained from detectors proposed in the past for the ISI channel, which are much easier to implement than conventional multiuser detectors of classical CDMA schemes. Another advantage of our scheme is that it leads naturally to a signal processing architecture similar to that of OFDM systems, hence based on the efficient FFT/IFFT algorithm. 相似文献
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The performance of a bandwidth-efficient multiple-tone modulation scheme for M -ary frequency-shift keying (MFSK) is presented. The use of balanced incomplete block (BIB) designs is proposed to form the signaling frames. On each symbol interval the modulator selects a group of elements from a BIB design and divides its energy into the orthogonal waveforms corresponding to these elements. The multiple-tone FSK scheme based on these block designs is shown to increase greatly the bandwidth efficiency of a conventional M -ary FSK system. An implicit diversity is incorporated in the modulation scheme. Thus, a performance improvement comparable to that obtained by using time or frequency diversity is shown on a Rayleigh fading channel and also on an interference channel with partial-band Gaussian noise. The multiple-tone scheme based on this design is compared to a multiple-tone scheme based on Hadamard matrices suggested by J.F. Pieper et al. (1978). It is shown that similar performance is achieved on a fading channel, while an advantage close to 4 dB is obtained for the proposed scheme on an AWGN (additive white Gaussian noise) channel 相似文献
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XieHongmei YuBianzhang ZhaoJian 《电子科学学刊(英文版)》2004,21(6):471-475
A mixed scheme based on Wavelet Transformation (WT) is proposed for image edge detection. The scheme combines the wavelet transform and traditional Sobel and LoG (Laplacian of Gaussian) operator edge-detection algorithms. The precise theory analysis is given to show that the wavelet transformation has an advantage for signal processing. Simulation results show that the new scheme is better than only using the Sobel or LoG methods. Complexity analysis is also given and the conclusion is acceptable, therefore the proposed scheme is effective for edge detection. 相似文献
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Seong Rag Kim Jeong Goo Lee Hun Lee 《Electronics letters》1996,32(23):2115-2117
The authors propose a new interference cancellation (IC) scheme which has a hybrid structure of the successive IC scheme and the parallel IC scheme. Based on computer simulation results, it is observed that the proposed IC scheme outperforms these two IC schemes for CDMA systems 相似文献
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Mobile Ad hoc Network (MANET) is a wireless technology for mobile nodes. This network is setup on fly without any infrastructure.
The mobility nature of this network and the lack of infrastructure make it very challenging to be secured. In this paper,
we introduce a formal model for Identity-based RSA (Id-RSA) scheme proven secure in the random oracle model. The proposed
scheme relies on establishing fast cryptography operations to enhance the network performance. We compare our scheme with
RSA-based Threshold Cryptography scheme (RSA-TC) and ECC-based Threshold Cryptography scheme (ECC-TC) in terms of speed and
overheads caused by the security messages. We show that the threshold cryptography operations involved in RSA-TC and ECC-TC
schemes cause a lot of overheads and delay. We implement these three schemes using the JAVA-based simulation framework (JIST/SWANS).
The results show that our Id-RSA scheme is more suitable for MANET mobility environment that require lightweight and secure
solutions. 相似文献
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In this paper, we present a simple pipeline paging (PP) scheme, in which multiple paging requests (PRs) can be served in a pipeline manner in different paging areas. We analytically model the blanket paging (BP) scheme, the sequential paging (SP) scheme, and the PIP scheme so that discovery rate, total delay, paging delay, and cost are derived analytically as functions of traffic load. Extensive simulations are carried out to verity our analytical results. Our study shows that the PIP scheme outperforms both the BIP and SIP schemes in terms of discover rate while maintaining the same cost as the SIP scheme. The PIP scheme outperforms the SP scheme in terms of total delay and has a lower total delay than the BIP scheme when traffic load is high. We also show that, when the paging delay constraint D is large enough, the PIP scheme achieves almost 200 percent of discovery rate and 50 percent of cost of the BP scheme, whereas discovery rate of the SIP scheme is far less than that of the BP scheme. Furthermore, we solve the following two-optimization problems for the PIP scheme: 1) the minimization of discovery rate with a bound on total delay and 2) the minimization of cost with a bound on total delay. In case the cost factor is not considered but total delay is important, we propose an adaptive scheme: When the traffic is lower than a threshold, the BIP scheme is adopted; otherwise, the PIP scheme is used. In this case, the threshold value is explicitly derived. 相似文献
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Image watermarking scheme using visual model and BN distribution 总被引:5,自引:0,他引:5
A watermarking scheme for digital images that is based on the characteristics of the human visual system is presented. The watermarking scheme inserts a perceptually invisible watermark in the discrete cosine transform domain. It is shown that the proposed scheme provides better results than two other popular schemes in terms of both transparency and robustness 相似文献