An effective automatic detection system for multi-protocol attack

Since there exists multi-protocol attack when several security protocols are co-executed in a computer network, an automatic detection system for multi-protocol attack (ADMA) is proposed. The system is composed of two parts named protocol search subsystem and attack verification subsystem. According to the consistency condition of the type of encrypted messages between the target protocol and the secondary protocol, the protocol search subsystem can automatically search for the candidate secondary protocols, which may be used to attack the target protocol. By improving the SAT-based model checking, attack verification subsystem can automatically verify whether multi-protocol attack exists between the target protocol and the candidate secondary protocols or not. The experiment results show that ADMA system can implement automatic detection for multi-protocol attack, and some new multi-protocol attacks are found in the detection.     

Hilbert-Huang transform and denoising for partial discharge ultrsonic singals of large motor

Empirical mode decomposition (EMD) algorithm is introduded as the core of the Hilbert-huang transform (HHT), and implementation process of EMD is analyzed. Then data compression denoising algorithm based on EMD is proposed, simulation and experimental signals are used for verification of the effect of EMD. In the same data sources, the comparison of data compression denoising approaches based on the EMD, db2 wavelet and db8 wavelet are conducted. In addition, physical experiment of the same analysis and comparisons are conducted on a running motor in a Chongqing electrical plant. Simulation and experimental results show that data compression denoising algorithm based on EMD can achieve the same denoising effect, or even better than based on db2 wavelet, db8 wavelet. The former is more perfect than the latter in the real signal processing, and denoising based on EMD is not loss of the original signal energy.     

Embedded terminal receiving capability matching in multimedia file transmission

A novel transport protocol for large scaled multimedia file EMFTP (Embedded Multimedia File Transfer Protocol) is proposed to match the receiving capability of embedded terminal with sufficient network bandwidth. EMFTP is an application level protocol using UDP, and adopts a method of uniform retransmission as its error recovery strategy and it also introduces an improved DAIMD (AIMD with decreasing increases) rate control algorithm based on bandwidth probe. It can improve the data transfer rate with a low resource taken of embedded client. As the experimental result shows, compared with UDT and FTP protocol implemented on embedded terminal, EMFTP data transfer rate is increased by 3% and 17% respectively, the embedded client CPU occupancy ratios are reduced by 50.3% and 42.3% separately, and memory usage reduced by 15% and 4%.     

Watermarking algorithm based on statistical property

A novel robust blind watermarking algorithm in DCT domain was proposed. The DCT coefficients are arranged in a specific way, and then the watermark is embedded based on odd even difference for optimal embedding. This algorithm works in a new pattern other than block division and search of the DCT coefficients in the middle frequencies in the traditional pattern, which can overcome the problem in searching suitable coefficients in the middle frequencies for watermark embedding and the small embedding capacity. Experimental results show that the algorithm is simple and good at perceptual transparency as well as robustness against noise and JPEG compression.     

Logistic map controlled secure arithmetic coding and its application in image encryption

A logistic map controlled secure arithmetic coding is proposed, the Logistic map is used to control the order of the symbols in the model and change the probabilities of the symbols, which is applied to the image encryption. The proposed scheme makes the image transmit more secure and comfortably on the Internet, and that is done at little expense in terms of coding efficiency. In the coding process, it ensures the uniformity of the model being changed by the chaotic sequence, thus to meet the security requirements of image compression. The algorithm can be applied to any arithmetic codec based on multimedia data including video, image and audio. Its most strength compared with other cipher mode is that, there is a significant reduction in the redundancy of information during the compression process, and it is robust when attempting to estimate the information of the image and discovering the key. The scheme can effectively resist differential analyses from both cryptography and coding.     

Framework of M-channel Systems and the Best Symmetric Extension

In image compression based on wavelet transform, the borders of images have to be processed in advance so as to reduce the distortions around the borders. An efficient way for this problem is symmetric extension. There are different types of symmetric extension methods. The paper presents the best symmetric extension and gives a design algorithm. Using the algorithm, we obtain the scheme of extending and windowing the signals in general best M-channel analysis/synthesis system.     

A Kind of Adaptive Generalized Predictive Control for a Nonlinear System

This paper,using Hammerstein model to express a kind of nonlinear system,presents a new kind of Adaptive Generalized Predictive control for Nonlinear systems(NAGPC). This method divides the whole system into two parts: linear subsystem and nonlinear one. In the first part,a new algorithm ,whose computation quantity is less and speed is faster,is developed according to the characteristics of gain controlling Matrix F in the Generalized Predictive Control (GPC). Mean while, the interpolation method is used to develop one step root solving procedure and the result can be used as the whole system input in the second part. Simulation studies show that the general algorithm NAGPC is strong in robustness,good in stability and fast in computation.     

An image encryption and compression algorithm based on chaos system and wavelet transform

An image encryption and compression algorithm based on chaos system and discrete wavelet transform (DWT) is studied in this paper.Firstly,four original secret images are transformed by DWT,and then the four low-frequency components are used to compose a two-dimensional coefficient matrix.The matrix is scrambled and encrypted by the chaos system,and then encrypted coefficient matrix is decomposed into four two-dimensional coefficient matrixes.Finally,an encrypted compressed image is obtained by the inverse DWT using the four decomposed two-dimensional coefficient matrices.Encryption and compression are realized at the same time in this algorithm which realizes the combination of chaos and wavelet transform,the experimental simulation and analysis show that the algorithm has good encryption and compression performance.     

Lossless compression of hyper-spectral interference image based on principal-modulated prediction

A lossless compression algorithm of hyper-spectral interference image based on principal-modulated prediction is proposed. Hyper-spectral interference images are divided into the space direction and the optical path difference(OPD) direction. In the space direction,a principal component prediction algorithm is used to reduce the inter-frame redundancies. And a modulated component prediction is used to reduce the spectral redundancies in the OPD direction. A two-step prediction algorithm is proposed for the principal component prediction. In the first step of prediction,a four order predictor is used to obtain a prediction reference value. In the second step,an 8-level lookup tables’ prediction algorithm is proposed and used to obtain the real-prediction. Then the final prediction is obtained through comparison between the real value and the reference prediction. A linearity prediction is used to obtain modulation prediction frame in the modulated component prediction. Finally,the final prediction frame is obtained through comparison between the principal component frame and the modulated component prediction frame. And the residual frame is obtained,which is encoded by an entropy coder. The experiments results show that the average compression ratio of proposed compression algorithm is reached to 3.05 bpp. Compared with traditional approaches,the proposed method can improve the average compression ratio by 0.14~2.94 bpp. They effectively improve the lossless compression ratio for hyper-spectral image lossless compression.     

An improved HEED clustering algorithm for Wireless Sensor Network

In wireless sensor network, routing protocols which based on clustering have the advantages of energy consumption, topology management and data fusion. The HEED protocol, which generates cluster heads based on distributed algorithm, drives up the rate of clustering and creates well distributed cluster heads. However, it does not consider the mobility of nodes in the network. When the distance between neighbor nodes has changed, the AMRP method which decides the node belongs to different cluster heads would cause problems such as high energy consumption, short lifetime of network and so on. Responding to these problems, the paper proposes the S HEED, a clustering algorithm based on stability, which chooses the stability as a parameter of nodes when choosing a cluster head. With S HEED algorithm, the high energy consumption problem among cluster nodes and cluster heads caused by the mobility is tackled. The simulation experiment demonstrates that the S HEED algorithm lower the energy consumption of cluster heads and prolongs the network lifetime.     

Modern Network Design

Nowadays the network of high-speed and broadband is required in the application of multimedia technology and information community. Many methods, such as network layering design, address design and routing are introduced to design Enterprise Backbone Network VPN's interrelation protocol is disposed and VPN tunnel is cut to establish virtual private network. Server and run plane design, bowels IP address distribution and network security advisement to design Intelligent Residential Area Network are given. It is pointed out that the method of modern network designs satisfies high-speed, intelligent and broadband for the developments of network technology.     

Analysis of Kinematic and Kinetic Characteristics of a Metal Pushing V Belt CVT

Based on the kinematic and kinetic characteristics, the friction model of a metal pushing V(belt continuously variable transmission (CVT) is established in this paper. The relation between applied forces and speed ratio as well as transmitted torque is analysed. The coputational formulas on the tension forces of steel ring and compression forces between metal blocks are derived. The theoretical bases for designing a metal pushing V belt CVT equipment and its control system are provided.     

A Kind of Robust Identification Algorithm Research

A new robust identification algorithm which is based on the estimation of parameter model,i.e.,Optimal Volume Ellipsoid parameter set identification algorithm is presented in this paper.It identifies not only a parameter point(the center of the ellipsoid) but also the error bounds of each parameter.It employs noise bounds in identification algorithm and dynamically modifies coefficients of identification convergent speed and direction in order to attain satisfactory perfomance.Digital simulation results show that is possesses high accuracy,dramatic convergent speed,excellent performance against noise and strong robustness as well as uniform convergent,which is obviously superior to traditional identification schemes.     

Controlling Techniques of Channel Sharing in HFC Network

The techniques of sharing a channel in HFC are original with regard to those of Ethernet and Ring. In this paper, the analysis is stressed on the method of the upstream bandwidth allocation, the collision resolving, and the relationship among them, beginning with MAP management message. The MAP is a complex frame, in which the messages of ranging opportunity needed by the CM at the access beginning, bandwidth allocation contention, bandwidth allocation and collision detection are included. The access way for a user is explained after the frame format and functions of a MAP are illustrated. Finally, upstream bandwidth allocation, the cause of collision, algorithm and the process to solve the collision and so on are studied.     

Application of Multidimensional Scaling in the Analysis of Spatial Ground Motion

In order to search for a tool to test whether the earthquakes is reasonable for the design, a method based on multidimensional scaling (MDS) and the dynamic time warping distance (DTW) was proposed, which represents the dissimilarities of earthquake in a low dimensional space in a visualized way and uncovers hidden structure of earthquake. The analysis of record from the seismic array shows that the proposed method can be a powerful tool in detecting the correlation structure of spatial ground motion as well as verifying whether the algorithm is producing properly correlated motions in space.     

Traffic Engineering and Traffic Matrix in IP Backbone Network Based on MPLS

On current network actuality and development trend, it is necessary to put traffic engineering in practice in IP backbone network on IP/MPLS. The essential demand in actualizing traffic engineering is traffic matrix measurement. After analyzing the defect of current measurement method, traffic engineering model and traffic matrix on LSP in IP backbone network based on MPLS, or relevant routing algorithm are researched. The merit of the traffic matrix's measurement method is that implement of measurement is only located in the edge node; therefore, network resource's cost is lower and it offers a new train of thoughts for resolving the flaw of current main measurement methods, moreover, and condition for actualizing traffic engineering.     

public-key Encryption Based on Torus Automorphisms

Chaotic maps with its characteristic are very useful in cryptography, however, compared with wide application in symmetric system, the research about chaos in public-key encryption system is still few. Through analysing the period of toms automorphisms which is a prototype of chaotic map, and making use of the framework of the traditional public-key algorithm RSA, the authors propose a chaotic public-key encryption algorithm based on toms automorphisms. Its security is based on the intractability of the integer factorization problem as RSA, and it is able to resist the chosen-ciphertext attack against RSA and easy to be implemented.     

LDPC encoding and decoding design based on Verilog HDL

LDPC (low density parity check code) is one of the most excellent codes,and it is a strong competitor of the fourth generation communication system (4G) as its performance is close to Shannon transmission limit.The paper realizes LDPC encoding and decoding algorithm through Verilog to improve computational efficiency,and selects π rotation matrix construction method to encode.And queen algorithm avoids the appearance of Cyclotella in H matrix.The UMP BP-based algorithm is also used in decoding and all of decimal fractions are limited between -100 and 100.For a large number of decimal fractions,the Q8 (fixed-point) format is adopted to express them and the range is between -128 and 127.996 093 75 with the precision of 0.003 906 25.Thus floating-point arithmetic can be avoided and Verilog language can be used to describe the LDPC decoding algorithm.The program does not use any IP core,which means it can be applied to all FPGAs and has good transplantation.It has high application value in engineering.     

Disassembly Process Planning of Products Based on Matrix Operation

Based on fuzzy Petri nets, a fuzzy reasoning Petri nets (FRPN) model is defined. And then, combining fuzzy Petri nets with matrix operation, an algorithm of formalized fuzzy reasoning process is proposed. Based on the fuzziness and uncertainness of the knowledge in the disassembly process of products, a decision making model in disassembly process is established. Furthermore, taking realistic disassembly as an example, an algorithm of decision-making in disassembly sequence is discussed. The result shows that the model of decision-making has strong parallel operation ability in the disassembly process sequence. It also can make intelligent decisions based on the product information originating from each disassembly step.