Assurance reconfiguration technology in decentralized database systems by an autonomous restructure mobile agent

Automata walking on graphs are a mathematical formalisation of autonomous mobile agents with limited memory operating in discrete environments. This paper establishes a framework in which to model and automatically verify that autonomous mobile agents correctly perform their tasks. The framework consists of a logical language tailored for expressing agent tasks, and an algorithm solving the parameterized verification problem, where the graphs are treated as the parameter. We reduce the parameterised verification problem to classic questions in automata theory and monadic second order logic, i.e., universality and validity problems.We illustrate the framework by instantiating it to a popular model of robot from the distributed computing literature.This work clarifies the border between classes of mobile-agent systems that have decidable parameterised verification problem, and those that do not.

Autonomous Mobile agents can be extremely useful in dynamic environments that require a continuous network connection. Network bandwidth reduction, protocol encapsulation, software automation and intelligence gathering can significantly affect Web Services. Integrating mobile agents with Web Services enables software adaptation to cope with a dynamic environment, automated system configuration and application requirement changes that are frequent in today''s ever fast-evolving technology. In this paper, we use a lightweight and efficient composition for mobile agents based Web services complying with Representational State Transfer (REST) principles for agent creation, migration, and control. The paper presents the overall concept and architecture of RESTful agents for web services. A security scheme is proposed for mobile agent security based on an infrastructure-less Identity Based Encryption (IBE) scheme integrated with Broadcast based Secure Mobile Agent Protocol (BROSMAP). A proof- of-concept implementation is provided.

Recently, market and user preferences have been drastically changing; user oriented production and logistic systems such as the supply chain management system have been required. In this kind of system, different subsystems with heterogeneous level of reliability have to coexist while trying to preserve the one click response and the flexibility in order to satisfy the frequently changing and heterogeneous preferences of the users. Thus assurance is required. An autonomous decentralized database system is proposed in order to realize the assurance. In this architecture, every site can autonomously control its own database within a permissible value, and coordinate among the sites by a mobile agent. Moreover, the autonomous consistency coordination technique is proposed in order to solve the problem of integrating and keeping the consistency of DB systems with heterogeneous levels of reliability. This technique is based on the inherent properties of autonomous decentralized systems (ADS) to attain the on-line property by the use of a data field among the replicated sites. Furthermore, an evaluation of the proposed technique is showed.

We present ongoing research concerning the interaction between users and environmental agencies through autonomous mobile agents in the environmental monitoring domain. The overarching EU FP7 project DIADEM, concerns the development of a system that detects potentially hazardous situations in populated areas using input from both a distributed sensor network and humans through their mobile devices. We propose a model of interaction with a system where concerned citizens communicate with a social virtual agent through their mobile phone to inform the environmental monitoring agency about unusual smells. In case of an emergency, people will receive instructions or directions for evacuation from the agent. In this paper, we review relevant literature and describe the development of a dynamic dialogue agent that supports international collaboration by adapting its social interaction to the cultural background of the humans it interacts with.

This paper proposes a language called CLAIM for computational language for autonomous intelligent and mobile agents. CLAIM allows to design multi-agent systems that support both stationary and mobile agents. Agents designed thanks to CLAIM are endowed with cognitive capabilities (e.g. reasoning), are able to communicate with other agents (send and receive several kinds of messages) and are mobile. The primitives of mobility are inspired from the ambient calculus. The CLAIM language is supported by a multi-platform system (SyMPA) compliant with the standard MASIF (OMG specifications); i.e. agents can be distributed over several sites and can move from one to another with respect to MASIF specifications. This paper presents the main features of our language CLAIM and an example to illustrate its applicability.

This paper addresses networked control problems which arise in the coordinated motion control of autonomous and semiautonomous mobile agents, where the sensors and controllers are geographically separated and connected by digital communication channels carrying a finite number of bits per unit time. Different from the existing results, this case with quantized output measurements and limited data rates is considered. A quantization, coding and control scheme is presented under communication constraints. In particular, it is shown that the unstable plant may be stabilizable in the mean square sense if the data rate of the channel is greater than the lower bound proposed in our results. Simulation results show the validity of the proposed scheme. DOI: http://dx.doi.org/10.11591/telkomnika.v10i8.1192 Full Text: PDF

Due to the advancement in the Information Technology, different kind of companies with heterogeneous needs have had the necessity to cooperate among them to get more benefit in a continuous changing market. That is heterogeneous e-business. In order to cope with such kind of e-business, a platform which can effectively realize heterogeneous needs, real time, flexibility and fault-tolerance is needed. This paper focuses on the database field that is indispensable for the e-business. Thus, it proposes Autonomous Decentralized Database System, which is composed of two techniques. In the first one, the concept of Allowable Volume (AV) is introduced, while in the second one, a Mobile Agent (MA) that adjusts the AV of each site is shown. Since the MA is always moving among the sites, and each site can always negotiate AV with the MA autonomously, the system can realize assurance. Furthermore, the effectiveness of the proposed system is shown by simulation.

Due to the progress of information technology, the business market is changing its strategy for a modern online business environment. Autonomous decentralized database system (ADDS) has been proposed in order to meet the innovative e-business requirements. In case the system size increases, a multiple-agent-based coordination is proposed for achieving the timeliness property. The response time is conformed by those transactions that require coordination and those that can be satisfied immediately. In this sense, the distribution of the data in the system for coordination is a medullar issue for the improvement of the response time. A trade-off exits between these two kind of transactions depending on the capacity of allocating data among the sites and the distribution of the data and user requests in the system. A study of the trade-off and the factor that need to be considered for an allocation data technology in order to get an optimal response time is discussed.

In recent years, there have been an increasing number of achievements dealing with the control of agent formations (Olfati-Saber, 2006; Tanner & Jadbabaie, 2007; Fax & Murray, 2004; Jadbabaie et al., 2003; Lin et al., 2004; Olfati-Saber & Murray, 2004). The formation control of multiple moving agents has emerged as a topic of widespread interest due to its broad range of applications in military missions, environmental surveying, and space missions. Multiple mobile autonomous agents coupled with each other through interactions can generate certain ordered behaviors, such as aggregation, cohesion, alignment, rotation and synchronization (Fax & Murray, 2004; Jadbabaie et al., 2003; Lin et al., 2004; Olfati-Saber & Murray, 2004). Among the typical approaches to formation control, distributed control strategies have aroused researchers’ outstanding attention because there is no centralized supervisor and only a little sense of communication information is needed. Recently, there has been a tendency to deal with the formation control as a consensus problem. In the multiagent systems, consensus means to reach an agreement by means of an interaction rule that specifies the information exchange between an agent and its neighbors (Fax & Murray, 2004; Jadbabaie et al., 2003; Lin et al., 2004; Olfati-Saber & Murray, 2004). Fax & Murry (Fax & Murray, 2004) analyzed the stability of the formation control with first-order consensus protocols based on the graph Laplacian. Jadbabaie et al. (Jadbabaie et al., 2003) demonstrated the results of the alignment problem which is concerned with reaching an agreement without computing any objective functions. Lin et al. (Lin et al., 2004) studied three formation strategies for groups of mobile autonomous agents with local communication topology. Moreover, by using a Lyapunov-based approach, Olfati-Saber & Murry (Olfati-Saber & Murray, 2004) solved the consensus problems in networks of agents with directed interconnection graphs and time delays. The key idea involved in nonlinear formation control is to preserve the inter-agent distances from decaying to zero during the motion for the purpose of collision avoidance. In the formation control, tracking control problems of multi-agent systems are studied increasingly, and many results have been obtained with nearest neighbor-based rule (Hong et al., 2006; Anderson et al., 2007; Chen & Tian, 2009). Hong et al. (Hong et al., 2006)

Agent-based distributed problem solving environments decompose a given problem into a set of sub problems which can be processed in parallel and independently by autonomous and mobile agents at each computation node. Such an autonomous agent primarily makes use of local information which is provided at the respective computation node. This kind of information is characterized by its potential incompleteness and inconsistency with regard to the overall distributed system state which is due to the lack of any centralized coordination facility. In this paper, we introduce the use of long-term knowledge repositories for autonomous agents without sacrifying the autonomy of the agents and without introducing any central management facility. We compare our approach to an agent-enabled distributed SAT prover which makes only use of local system state information. In that problem solving application a given search tree is distributed dynamically by autonomous mobile agents implemented in pure Java. To demonstrate the profit of using knowledge repositories in general, we integrated our agent system Okeanos into our XML-based monitoring system Specto and the lightweight, distributed event-based middleware Mitto. Our cooperative approach does not conflict with the decentralized parallelization algorithm of the distributed SAT prover. Empirical results show that our approach can contribute to the performance of distributed symbolic computation. In this example, a load balancing subsystem is implemented taking the now available global information about the system state appropriately into account.KeywordsMobile AgentAutonomous AgentComputation NodeTuple SpaceKnowledge RepositoryThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

The mobile-agent-based approach is a programming paradigm for data collection within WSNs (Wireless Sensor Networks) in which data gathering tasks are carried out by autonomous mobile agents. Such agents allow a great degree of flexibility and robustness regarding which data is collected and in what manner. Rationality plays a crucial role in deciding energy efficiency of the agents. This paper studies the evaluation and comparison of differing solutions, namely bold, cautious, and utilitarian agents within time threshold on Sensorworld platform. Simulation results prove that the higher the intelligence level, the better the performance of the agent.

This paper is concerned with the collective behavior of a group of $n>1$ mobile autonomous agents, labelled $1$ through $n$, which can all move in the plane. Each agent is able to continuously track the positions of all other agents currently within its “sensing region,” where by an agent's sensing region we mean a closed disk of positive radius $r$ centered at the agent's current position. The multi-agent rendezvous problem is to devise “local” control strategies, one for each agent, which without any active communication between agents cause all members of the group to eventually rendezvous at a single unspecified location. This paper describes a family of unsynchronized strategies for solving the problem. Correctness is established appealing to the concept of “analytic synchronization.”

Generalized Controller for Directed Triangle Formations

Sensor and network topologies of rigid formations with distance information between mobile autonomous agents are considered. An approach based on rigidity for creating such topologies was suggested in our previous work. Here, we first illustrate some potential scenarios on formations that require unambiguity in the knowledge of distances between every pair of agents in a formation. Then, we show how a stronger type of rigidity, namely global rigidity, plays a role in creating such unambiguous formations. We draw out and summarize some relevant results from the related mathematical theory of global rigidity; and present some new results on globally rigid formations.

We study a problem of blanket coverage by employing a network of self-deployed, autonomous mobile sensors or agents. The coverage problem is to drive the mobile sensor network to form a sensor lattice that completely covers a two-dimensional (2-D) region between two boundaries. In particular, the sensors form into the so-called triangular lattice pattern, and it is optimal in terms of the minimum number of sensors required for complete coverage of a bounded 2-D set. A distributed motion coordination algorithm is proposed for the mobile sensors to address the coverage problem. The algorithm is developed based on some simple consensus algorithms that only rely on local information. To illustrate the proposed algorithm, numerical simulations have been carried out for a number of scenarios.