3179831
RNS application for digital image processing
In this paper, we carry out a study on the RNS (residue number system) application in digital image processing and propose a RNS image coding scheme that offers high-speed and low-power VLSI implementation for secure image processing. The proposed scheme is more efficient than the RNS image coding scheme of Ammar et al. (2001) in that the proposed method encrypts the entire image and does not require any additional component other than a standard RNS system. Further, the proposed scheme is based on the modified CRT and its associated residue-to-binary conversion and moduli selection methods and is more efficient than the scheme by Ammar et al. (2001) in terms of VLSI implementation. The design of an encoder and decoder pair for the greyscale image is carried out using MATLAB tool and some VLSI tools. The preliminary results of the Matlab simulation demonstrate the security ability of the proposed image coding scheme.
31496165
Elliptic curves cryptosystem implementation based on a look-up table sharing scheme
Projective point elliptic curve cryptography (ECC) involves many look-up table-based field multiplications. In this paper, a novel lookup table sharing scheme is proposed to significantly reduce the number of the field multiplications and number of lookup tables. By requiring much less lookup table generation time, the proposed system offers high-speed performance for hardware realizations. Its application in a reconfigurable PC-FPGA platform is investigated, which can efficiently handle requests for different ECC key length and curves and is useful for many computer network applications
15012785
An area-reduced scheme for modulo 2/sup n/-1 addition/subtraction
In this paper, we present a versatile area-reduced scheme for modulo 2/sup n/-1 adders and subtracters using a MUX-based increment/decrement algorithm. A FPGA-based comparison of the proposed modulo adder and the conventional modulo adder designs is carried out. The implementation results show that the proposed adder reduces the area close to 30% compared with the modulo adder of Bayoumi et al. The delay and the power are also reduced around 10%. In addition, it is also shown that the proposed design requires less hardware resources than the parallel-prefix modulo adder of Kalampoukas et al. while providing a comparable operation speed.
15644746
RRNS quasi-chaotic coding and its FPGA implementation
In this paper, a new architecture of the redundant residue number system (RRNS) based quasi-chaotic coding is proposed for the secure telecommunication systems and networks. In the proposed architecture, a number of modulo operations required by the existing designs are replaced by binary coding operations to simplify the design. Also, a moduli selection method and a residue-to-binary converter with error-correction capability are proposed to further improve the efficiency of the design specifically for FPGA implementation. The proposed architecture is implemented and tested using Matlab and Xilinx FPGA hardware. The results show that compared to the existing design, the proposed design requires only 80% of the hardware resources while maintaining the same speed. The power consumption is also reduced by 25%.
29715580
A high-speed residue-to-binary converter and a scheme for its VLSI implementation
In this paper, a high-speed residue-to-binary converter for the recently introduced moduli set (2/sup k/, 2/sup k/-1, 2/sup k-1/-1) is proposed. Compared to the previous converter based on this moduli set, the proposed one is 40% faster; also, the time-complexity product is improved by 20%. Following the VLSI design flow established by the Canadian Microelectronics Corporation, the proposed converter is implemented in 0.5-micron CMOS technology. Based on this moduli set, layouts of the 8-bit, 16-bit, 32-bit and 64-bit residue-to-binary converters which can be used in further RNS system designs, are generated and simulation results obtained.
29637234
A new architecture of RRNS error-correcting QC encoder/decoder and its FPGA implementation
In this paper, a new architecture of a redundant residue number system (RRNS) quasi-chaotic (QC) encoder/decoder with an error-correcting ability is proposed for secure communication and is tailored to FPGA implementation. In the proposed architecture, binary subencoders and subdecoders are used so that a number of modulo operations required in the existing design of D. R. Frey (IEEE Trans. Circuits Syst. II, vol. 40, pp. 660-666, Oct. 2000) are replaced by a simple truncation. Furthermore, a size-reduced design of the R/B (residue-to-binary) converter with error-correcting function, which is the crucial part of the system, is proposed. As a case study, the proposed architecture is implemented in FPGA for the case of the 16-bit input and some simulation results obtained.
1993887
Locating Motifs in Time-Series Data
Finding motifs in time-series is proposed to make clustering of time-series subsequences meaningful, because most existing algorithms of clustering time-series subsequences are reported meaningless in recent studies. The existing motif finding algorithms emphasize the efficiency at the expense of quality, in terms of the number of time-series subsequences in a motif and the total number of motifs found. In this paper, we formalize the problem as a continuous top-k motif balls problem in an m-dimensional space, and propose heuristic approaches that can significantly improve the quality of motifs with reasonable overhead, as shown in our experimental studies.
29222863
An adaptive approach for image encryption and secure transmission over multirate wireless sensor networks
In this paper, we propose an innovative adaptive secure image delivery approach, to achieve effective and efficient image encryption based on an optimal transmission rate in terms of energy efficiency in wireless sensor networks (WSN). Our contribution is three folds—First, the proposed component based selective encryption scheme achieves high image security, while incurring little encryption overhead; furthermore, the proposed adaptive encryption scheme achieve the best security effort within delay bound; finally, the proposed transmission rate optimization improves energy efficiency, and feeds back effective path capacity parameters for adaptive encryption. Simulation results show a significant gain in both energy efficiency and security based on the proposed approach for image secure transmissions in WSN. Copyright # 2007 John Wiley & Sons, Ltd.
10066890
Quantile-based KNN over multi-valued objects
K Nearest Neighbor search has many applications including data mining, multi-media, image processing, and monitoring moving objects. In this paper, we study the problem of KNN over multi-valued objects. We aim to provide effective and efficient techniques to identify KNN sensitive to relative distributions of objects.We propose to use quantiles to summarize relative-distribution-sensitive K nearest neighbors. Given a query Q and a quantile φ ∈ (0, 1], we firstly study the problem of efficiently computing K nearest objects based on a φ-quantile distance (e.g. median distance) from each object to Q. The second problem is to retrieve the K nearest objects to Q based on overall distances in the “best population” (with a given size specified by φ-quantile) for each object. While the first problem can be solved in polynomial time, we show that the 2nd problem is NP-hard. A set of efficient, novel algorithms have been proposed to give an exact solution for the first problem and an approximate solution for the second problem with the approximation ratio 2. Extensive experiment demonstrates that our techniques are very efficient and effective.
33979500
Decentralized adaptive backstepping stabilization of interconnected systems with dynamic input and output interactions
So far there is still no result available for backstepping based decentralized adaptive stabilization of unknown systems with interactions directly depending on subsystem inputs, even though such interactions commonly exist in practice. In this paper, we provide a solution to this problem by considering both input and output dynamic interactions. To clearly illustrate our approaches, we will start with linear systems and then extend the results to nonlinear systems. Each local controller, designed simply based on the model of each subsystem by using the standard adaptive backstepping technique without any modification, only employs local information to generate control signals. It is shown that the designed decentralized adaptive backstepping controllers can globally stabilize the overall interconnected system asymptotically. The L"2 and L"~ norms of the system outputs are also established as functions of design parameters. This implies that the transient system performance can be adjusted by choosing suitable design parameters.
2629783
Optimal Rate-Based Image Transmissions via Multiple Paths in Wireless Sensor Network
Many sensor applications such as monitoring and surveillance may require image sensor array to conduct collaborative image transmissions in wireless sensor network (WSN). The large size image transmission in WSN is a bottleneck due to the limited energy resources. In this paper, we propose an optimal scheme for image sensors to utilize inter-sensor correlations to decide transmission patterns based on a multi-level rate-oriented routing (MLRR) routing scheme, which achieves high energy efficiencies and longer network lifetime. This optimization scheme allows each image sensor to transmit optimal fractions of the overlapped images through appropriate multiple rate-oriented routing paths. The simulation results by using GA algorithm show that the proposed image transmission scheme can achieve considerable gains in terms of the WSN energy efficiency and network lifetime extension.