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Membrane computing models are parallel and distributed natural computing models. These models are often referred to as P systems. This paper proposes a novel multi-behaviors co-ordination controller model using enzymatic numerical P systems for autonomous mobile robots navigation in unknown environments. An environment classifier is constructed to identify different environment patterns in the maze-like environment and the multi-behavior co-ordination controller is constructed to coordinate the behaviors of the robots in different environments. Eleven sensory prototypes of local environments are presented to design the environment classifier, which needs to memorize only rough information, for solving the problems of poor obstacle clearance and sensor noise. A switching control strategy and multi-behaviors coordinator are developed without detailed environmental knowledge and heavy computation burden, for avoiding the local minimum traps or oscillation problems and adapt to the unknown environments. Also, a serial behaviors control law is constructed on the basis of Lyapunov stability theory aiming at the specialized environment, for realizing stable navigation and avoiding actuator saturation. Moreover, both environment classifier and multi-behavior coordination controller are amenable to the addition of new environment models or new behaviors due to the modularity of the hierarchical architecture of P systems. The simulation of wheeled mobile robots shows the effectiveness of this approach.

© 2020 World Scientific Publishing Company. Optimization Spiking Neural P System (OSNPS) is the first membrane computing model to directly derive an approximate solution of combinatorial problems with a specific reference to the 0/1 knapsack problem. OSNPS is composed of a family of parallel Spiking Neural P Systems (SNPS) that generate candidate solutions of the binary combinatorial problem and a Guider algorithm that adjusts the spiking probabilities of the neurons of the P systems. Although OSNPS is a pioneering structure in membrane computing optimization, its performance is competitive with that of modern and sophisticated metaheuristics for the knapsack problem only in low dimensional cases. In order to overcome the limitations of OSNPS, this paper proposes a novel Dynamic Guider algorithm which employs an adaptive learning and a diversity-based adaptation to control its moving operators. The resulting novel membrane computing model for optimization is here named Adaptive Optimization Spiking Neural P System (AOSNPS). Numerical result shows that the proposed approach is effective to solve the 0/1 knapsack problems and outperforms multiple various algorithms proposed in the literature to solve the same class of problems even for a large number of items (high dimensionality). Furthermore, case studies show that a AOSNPS is effective in fault sections estimation of power systems in different types of fault cases: including a single fault, multiple faults and multiple faults with incomplete and uncertain information in the IEEE 39 bus system and IEEE 118 bus system.

Active worms can cause widespread damages at so high a speed that effectively precludes human-directed reaction, and patches for the worms are always available after the damages have been caused, which has elevated them self to a first-class security threat to Metropolitan Area Networks (MAN). Multi-agent system for Worm Detection and Containment in MAN (MWDCM) is presented to provide a first-class automatic reaction mechanism that automatically applies containment strategies to block the propagation of the worms and to protect MAN against worm scan that wastes a lot of network bandwidth and crashes the routers. Its user agent is used to detect the known worms. Worm detection agent and worm detection correlation agent use two-stage based decision method to detect unknown worms. They adaptively study the accessing in the whole network and dynamically change the working parameters to detect the unknown worms. MWDCM confines worm infection within a macro-cell or a micro-cell of the metropolitan area networks, the rest of the accesses and hosts continue functioning without disruption. MWDCM integrates Worm Detection System (WDS) and network management system. Reaction measures can be taken by using Simple Network Management Protocol (SNMP) interface to control broadband access server as soon as the WDS detect the active worm. MWDCM is very effective in blocking random scanning worms. Simulation results indicate that high worm infection rate of epidemics can be avoided to a degree by MWDCM blocking the propagation of the worms.

Information processing mechanism of visual image is the most important groudwork and core technology in artificial vision research. A information processing model of artificial vision is proposed based on the principle of acquisiting and processing of human visual information in this paper. Then its system architectures and key technologies is discussed.

The primary objective of this paper is to develop a simulation model in OPNET to implement direct sequence spread spectrum (DS-SS) code division multiple access (CDMA) system for formation flying of satellites. The focus of this paper is to model and implement seven-satellite formation, PN code generation, spreading and despreading. Simulation results are presented.

Microseismic is applied broadly but intra-pulse features of microseismic are not studied enough still. For exploring the chaos features of microseismic, the largest Lyapunov exponents and correlation dimension of pulse segment of four microseismic records are calculated. All the largest Lyapunov exponents of pulse segment of four microseismic records are greater than zero, and all their non-zero attractor of correlation dimension exists. The results show that microseismic is of chaos.

The general agent communication language (ACL) such as KQML is usually used to implement knowledge sharing and manipulating, and it is not suitable for the multimedia communication tasks that require fast real-time reaction and multi-round cooperation of the peers. Therefore, an agent communication language for multimedia communication task (ACLMC) is proposed to support this type of communication task. Compared to the general ACL, ACLMC has more cooperative primitives that can express the intention of agents more directly. More than that, the expression of the content layer can be more concise. A prototype of multi-agent based softswitch system is designed and implemented to verify the ACLMC language, which uses ACLMC to support the communication among agents. The results of experiment have verified the function and performance of ACLMC language designed in this paper.

Security auditing and worm containment is used to guarantee the network security in metropolitan area networks. Multi-agent system for security auditing and worm containment in MAN (MSAWCM) is presented to audit user's accesses and provide a first-class automatic reaction mechanism that automatically applies containment strategies to prevent clean host from being infected by blocking the propagation of the worms MSAWCM uses broadband access server as information gathering agent that uses hardware packet filter (HPF) to get packet from MAN. It adaptively studies and audits the accessing in the whole network and dynamically changes the working parameters to detect the unknown worms. MSAWCM integrates worm detection system (WDS) and network management system (NMS). Reaction measures can be taken by using SNMP interface to control BAS as soon as the WDS detect the active worm. MSAWCM is very effective in blocking random scanning worms that are very noisy and tend to waste a lot of network bandwidth and crash routers. Simulation results indicate that high worm infection rate of epidemics can be avoided to a degree by MSAWCM blocking the propagation of the worms.

Normally, security auditing is quite common in low bandwidth network, especially in 100M/IOM Ethernet. It is difficult to accomplish security auditing in broadband metropolitan area network (MAN) with Gigabit Ethernet or 2.5 GPOS (OC48) as its convergence layer backbone. This paper presents the Multi-agent based security auditing system of broadband MAN (MASASM) to resolve the problem. The key for auditing in MAN is how to get packets from MAN and how to overcome the processing of huge information. The usual ways of getting packets from network such as BSD Packet Filter (BPF) and tcpdump are not suitable for auditing in MAN at all. MASASM uses Broadband Access Server (BAS) of MAN as Information Gathering Agent that uses Hardware Packet Filter (HPF) io get packet from MAN. HPF has better process abilie than BPF and tcpdump. MASASM uses distributed multi-agent to share the task of auditing for whole MAN. To make the least influence on the performance of Information Gathering Agent, a new mechanism of routing and forwarding is given to modify the traditional "route once, switch many" to the "audit once, pass many" in BAS. The auditing system has been implemented in our experimental convergence layer routing switch that can be used as a BAS, and shows goad performance in test.

The forthcoming next generation network (NGN) is an all IP network. It should guarantee multimedia communications to traverse NAT and firewall. The existing traversal methods are not suitable for a service provider to set up a real system in the NGN. Multi-agent system for multimedia communication traversing NAT (network address translator) and firewall (MASMCT) is presented to resolve the problem. MASMCT is secure and easy for a service provider to set up. It has a two-layer multi-agent architecture and can be classified by client agents and server agents. Each of them in MASMCT is transparent for endpoint users and softswitch. They coact and relay call signaling message and media data between endpoint and softswitch. One of the paper's key aspects is an introduction to the mechanism and function model of MASMCT. We define the protocol of multiplexed connection for bundled session (MCBS); it is used by agents to communicate with each other, and may be the standard protocol in future NGN.