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By analyzing the existing problems and causes of the construction quality acceptance assessment of engineering projects, the idea of BIM-based construction quality inspection and assessment system architecture was proposed. Through the operation of the system, digital and paperless management of construction project archives was realized while the construction quality inspection and assessment was proceeded. Then it also analyzed the advantages of this system and put forward countermeasures to the possible problems during the operation process.

In order to solve the problem the existing vertical handoff algorithms of vehicle heterogeneous wireless network do not consider the diversification of network’s status, an optimized vertical handoff algorithm based on markov process is proposed and discussed in this paper. This algorithm takes into account that the status transformation of available network will affect the quality of service (QoS) of vehicle terminal’s communication service. Firstly, Markov process is used to predict the transformation of wireless network’s status after the decision via transition probability. Then the weights of evaluating parameters will be determined by fuzzy logic method. Finally, by comparing the total incomes of each wireless network, including handoff decision incomes, handoff execution incomes and communication service incomes after handoff, the optimal network to handoff will be selected. Simulation results show that: the algorithm proposed, compared to the existing algorithm, is able to receive a higher level of load balancing and effectively improves the average blocking rate, packet loss rate and ping-pang effect.

Lorenz systems family unifying Lorenz system, Chen system and Lu system is a typical chaotic family. In this paper, we consider impulsive control Lorenz chaotic systems family with time-varying impulse intervals. By establishing an effective tool of a set of inequalities, we analyze the asymptotic stability of impulsive control Lorenz systems family and obtain some new less conservative conditions. Based on the stability analysis, we design a novel impulsive controller with time-varying impulse intervals. Illustrative examples are provided to show the feasibility and effectiveness of our method. The obtained results not only can be used to design impulsive control for Lorenz systems family, but also can be extended to other chaotic systems.

We propose an impulsive control scheme for fractional-order chaotic systems. Based on the Takagi–Sugeno (T-S) fuzzy model and linear matrix inequalities (LMIs), some sufficient conditions are given to stabilize the fractional-order chaotic system via impulsive control. Numerical simulation shows the effectiveness of this approach.

A whole impulsive control scheme of nonlinear systems with time-varying delays, which is an extension for impulsive control of nonlinear systems without time delay, is presented in this paper. Utilizing the Lyapunov functions and the impulsive-type comparison principles, we establish a series of different conditions under which impulsively controlled nonlinear systems with time-varying delays are asymptotically stable. Then we estimate upper bounds of impulse interval and time-varying delays for asymptotically stable control. Finally a numerical example is given to illustrate the effectiveness of the method.

This paper deals with the exponential stability of impulsive Takagi–Sugeno fuzzy systems with delay. Impulsive control and delayed fuzzy control are applied to the system, and the criterion on exponential stability expressed in terms of linear matrix inequalities (LMIs) is presented.

The issue of impulsive control theory for synchronization of the MCK circuit is developed. We propose an impulsive control scheme for the complete synchronization of the MCK circuit including chaotic systems. A sufficient condition for the impulsive control is derived, with an easily calculated maximum impulsive interval. The proposed impulsive control scheme is applied to the MCK circuit and the simulation result demonstrates the effectiveness of the method.

The issue of impulsive synchronization of the coupled chaotic laser plasma system is investigated. A new framework for impulsive synchronization of such chaotic systems is presented, which makes the synchronization error system a linear impulsive control system. We derive some sufficient conditions for the synchronization of a laser plasma system via impulsive control with the varying impulsive intervals, which allows us to derive the impulsive synchronization law easily. To illustrate the effectiveness of the proposed results, two numerical examples are given.

This paper reports that an impulsive control theory for synchronization of nonlinear Rossler chaotic systems is developed. A new framework for impulsive synchronization between such chaotic systems is presented, which makes the synchronization error system a linear impulsive control system. Therefore, it is easy to derive the impulsive synchronization law. The proposed impulsive control scheme is illustrated by nonlinear Rossler chaotic systems and the simulation results demonstrate the effectiveness of the method.

In order to improve communication security, proposed a chaotic block cryptographic scheme based on the coupled piecewise nonlinear map. Using the coupled chaotic systems to generate random binary sequences, a key-dependent shift approach permuted the plain-text block and then using the classical chaotic masking technique encrypted the plain-text block. Simulation results show that the proposed algorithm has excellent cryptographic properties such as diffusion and confusion properties and it can resist the know plain-text attacks and chosen plain-text attacks.

In this paper, the layer-by-layer optimizing algorithm for training multilayer neural network is extended for the case of a multilayer neural network whose inputs, weights, and activation functions are all complex. The updating of the weights of each layer in the network is based on the recursive least squares method. The performance of the proposed algorithm is demonstrated with application in adaptive complex communication channel equalization.

In this paper, global asymptotic stability for cellular neural networks with time delay is discussed using a novel Liapunov function. Some novel sufficient conditions for global asymptotic stability are obtained. Those results are simple and practical than those given by P. P. Civalleri, et al., and have a leading importance to design cellular neural networks with time delay.

Discrete logarithm based cryptosystems have subtle problems that make the schemes vulnerable. This paper gives a comprehensive listing of security issues in the systems and analyzes three classes of attacks which are based on mathematical structure of the group which is used in the schemes, the disclosed information of the subgroup and implementation details respectively. The analysis will, in turn, allow us to motivate protocol design and implementation decisions.

In this paper, a new consensus problem is investigated which is group consensus. It contains such consensus problem as a special case that all agents in a network reach a consistent value asymptotically. Consider a dynamic multi-agent system with connected undirected or connected bipartite graph topology and delays, two novel consensus protocols are introduced to solve the group consensus problem. The convergence analysis is discussed and the sufficient condition for system group convergence is obtained based on the frequency-domain analysis and generalized Nyquist criterion, respectively. And we know that the condition of group convergence is only depended on system's time delay and the adjacent weight between the agents, meanwhile, delay can affect the dynamic characteristics of the system. Finally, simulations are provided to demonstrate the effectiveness of our theoretical results.

A joint of image encryption and compression is investigated, and a novel joint encryption and compression scheme is proposed. In our scheme, the encryption process is performed before compression. Making use of the properties of discrete wavelet transform (DWT) and Set Partitioning in Hierarchical Trees (SPIHT) coding, confusion is restricted to the interior of single subband image itself and so image details are retained. Furthermore, diffusion preserves the two most significant bits (MSBs) and the sign bit, which contain important information about the image. The experiments show that the proposed algorithm possesses a good visual quality of the reconstructed image and a high encryption speed.

The synchronization between two unknown chaotic systems is achieved by designing a controller based on the sliding mode control technique and radial basis function neural network. The controller design method is independent of the system mathematical model, but only depends on the output of the system state. Moreover, it is robust to parameter uncertainties and the outside interference. Finally, synchronization between unknown Lorenz systems and between unknown Lorenz system and Chen system are achieved using the proposed method. The response time is very short and the synchronization performance is good.