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The study of the use of mobile Apps plays an important role in understanding the user preferences, and thus provides the opportunities for intelligent personalized context-based services. A key step for the mobile App usage analysis is to classify Apps into some predefined categories. However, it is a nontrivial task to effectively classify mobile Apps due to the limited contextual information available for the analysis. For instance, there is limited contextual information about mobile Apps in their names. However, this contextual information is usually incomplete and ambiguous. To this end, in this paper, we propose an approach for first enriching the contextual information of mobile Apps by exploiting the additional Web knowledge from the Web search engine. Then, inspired by the observation that different types of mobile Apps may be relevant to different real-world contexts, we also extract some contextual features for mobile Apps from the context-rich device logs of mobile users. Finally, we combine all the enriched contextual information into the Maximum Entropy model for training a mobile App classifier. To validate the proposed method, we conduct extensive experiments on 443 mobile users’ device logs to show both the effectiveness and efficiency of the proposed approach. The experimental results clearly show that our approach outperforms two state-of-the-art benchmark methods with a significant margin. [ABSTRACT FROM AUTHOR]

We consider the gathering problem of multiple (mobile) agents in anonymous unidirectional ring networks under the constraint that each agent knows neither the number of nodes nor the number of agents. For this problem, we fully characterize the relation between probabilistic solvability and termination detection. First, we prove for any (small) constant p (0

Recently, as more and more mobile devices embedded with intelligent software become part of our daily lives, Open Services Gateway initiative (OSGi) has gained increasing attention in the development of services for such devices. However, services residing in OSGi platforms are devised specifically for the platforms' local bundles. Although several works have enhanced OSGi with various communication mechanisms that enable remote service invocations, two crucial issues pertaining to mobile computing remain to be addressed: One is limited resources of mobile devices, and the other is unstable links experienced with mobile devices. To address these two issues, we propose an itinerary-based mobile agent approach with four major features: To implement mobile agents as OSGi bundles to deliver distributed OSGi services with lower resource consumption; to extend WSDL and WS-BPEL to help developers design mobile agent itineraries; to provide an opportunistic service matchmaking mechanism allowing mobile agents to adapt to context changes at runtime; and to devise asynchronous communication mechanism to enable reliable mobile agent transmissions among mobile devices with dynamic IP addresses and intermittent connection to the Internet. Through experimental evaluations, we demonstrate that both network traffic and turnaround time of our approach are better than those of client-server ones. [ABSTRACT FROM AUTHOR]

This paper addresses cooperative search for multiple stationary ground targets by a group of unmanned aerial vehicles with limited sensing and communication capabilities. The whole surveillance region is partitioned into cells where each cell is associated with a probability of target existence within the cell, which constitutes a probability map for the whole region. Each agent keeps an individual probability map and updates the map individually with measurements according to Bayesian rule. A nonlinear transformation of the probability map is introduced to simplify the computation by linearizing the Bayesian update. A consensus-like distributed fusion scheme is proposed for multiagent map fusion. We prove that all the individual probability maps converge to the same one that reflects the true existence or nonexistence of targets within each cell. Coverage and topology control algorithms are designed for the path planning of mobile agents. Moreover, the performance of the fusion scheme for asynchronous implementations of sampling and communication is analyzed. Finally, the effectiveness of the proposed algorithms is illustrated via simulations. [ABSTRACT FROM PUBLISHER]

We examine a future distribution system capable of solving problems caused by the connection of numerous distributed generators. A supervisory-control-and-data-acquisition (SCADA) system for this distribution system should be economical, flexible, and reliable, and should execute a real-time process. In this paper, we propose a SCADA system using mobile agents for flexibility. In addition, we show two types of communication protocols that make agent migration more fault-tolerant, and perform experiments where the SCADA system executes earth fault protection within the required time. These results indicate that the SCADA system based on our proposed technologies should be capable of fulfilling the real-time processing requirement. [ABSTRACT FROM AUTHOR]

This paper presents a methodology to design a control law that can provably steer a group of mobile agents to a free-floating formation of specific shape, while avoiding collisions. We indicate why existing multiagent solutions have a theoretical limitation due to one of the working assumptions of the single-agent potential function approach being violated. A new nonsmooth type of multiagent potential functions is, thus, developed. It is shown how this extension of the navigation function concept to multiagent systems ensures the nondegeneracy of the critical points of the potential function. [ABSTRACT FROM AUTHOR]

In this paper, a novel decentralized control strategy for bilaterally teleoperating heterogeneous groups of mobile robots from different domains (aerial, ground, marine, and underwater) is proposed. By using a decentralized control architecture, the group of robots, which is treated as the slave side, is made able to navigate in a cluttered environment while avoiding obstacles, interrobot collisions, and following the human motion commands. Simultaneously, the human operator acting on the master side is provided with a suitable force feedback informative of the group response and of the interaction with the surrounding environment. Using passivity-based techniques, we allow the behavior of the group to be as flexible as possible with arbitrary split and join events (e.g., due to interrobot visibility/packet losses or specific task requirements) while guaranteeing the stability of the system. We provide a rigorous analysis of the system stability and steady-state characteristics and validate performance through human/hardware-in-the-loop simulations by considering a heterogeneous fleet of unmanned aerial vehicles (UAVs) and unmanned ground vehicles as a case study. Finally, we also provide an experimental validation with four quadrotor UAVs. [ABSTRACT FROM AUTHOR]

The subject of this paper is the patrolling of an environment with the aid of a team of autonomous agents. We consider both the design of open-loop trajectories with optimal properties and of distributed control laws converging to optimal trajectories. As performance criteria, the refresh time and the latency are considered, i.e., respectively, time gap between any two visits of the same region and the time necessary to inform every agent about an event occurred in the environment. We associate a graph with the environment, and we study separately the case of a chain, tree, and cyclic graph. For the case of chain graph, we first describe a minimum refresh time and latency team trajectory and propose a polynomial time algorithm for its computation. Then, we describe a distributed procedure that steers the robots toward an optimal trajectory. For the case of tree graph, a polynomial time algorithm is developed for the minimum refresh time problem, under the technical assumption of a constant number of robots involved in the patrolling task. Finally, we show that the design of a minimum refresh time trajectory for a cyclic graph is NP-hard, and we develop a constant factor approximation algorithm. [ABSTRACT FROM AUTHOR]

Compared with conventional wireless sensor networks (WSNs) operating based on the client–server computing model, mobile agent (MA)-based WSNs can facilitate agent-based data aggregation and energy-efficient data collection. In MA systems, it has been known that finding the optimal itinerary of an MA is nondeterministic polynomial-time hard (NP-hard) and is still an open area of research. In this paper, we consider the impact of both data aggregation and energy efficiency in itinerary selection. We first propose the Itinerary Energy Minimum for First-source-selection (IEMF) algorithm. Then, the itinerary energy minimum algorithm (IEMA), which is the iterative version of IEMF, is described. This paper further presents a generic framework for the multiagent itinerary planning (MIP) solution, i.e., the determination of the number of MAs, allocating a subset of source nodes to each agent and itinerary planning for each MA. Our simulation results have demonstrated that IEMF provides higher energy efficiency and lower delay, compared with existing single-agent itinerary planning (SIP) algorithms, and IEMA incrementally enhances IEMF at the cost of computational complexity. The extensive experiments also show the effectiveness of MIP algorithms when compared with SIP solutions. [ABSTRACT FROM PUBLISHER]

Network services in the future Internet are required to be highly available, ubiquitous, self-managing, and adaptable to dynamic environments. A promising way to implement such network services is combining mobile agent approaches with ecosystem-inspired evolutionary approaches. However, this perspective is still far from being practically implemented. An important reason is a lack of fundamental theory on macrodynamics of mobile agents in the new paradigm. This paper considers a type of large-scale mobile agent system and discusses the macrodynamics mainly affected by mobile agents' migration behaviors in the systems. The study benefits not only the design of composite services emerged from mobile agents in a type of ecosystem-inspired network architecture but also the future deployment of an Internet-scale system that holds myriads of mobile agents, hosts, and migratory behaviors of mobile agents. [ABSTRACT FROM PUBLISHER]

This paper presents a distributed coverage algorithm for a network of mobile agents. Unlike previous work that uses a simple gradient descent algorithm, here we employ an existing deterministic annealing (DA) technique to achieve more optimal convergence values since typical coverage objective functions contain many local minima. We replicate the results of the classical DA algorithm while imposing a limited-range constraint to sensors. As the temperature is decreased, phase changes lead to a regrouping of agents, which is decided through a distributed task allocation algorithm. While simple gradient descent algorithms are heavily dependent on initial conditions for such non-convex coverage objective functions, annealing techniques are generally less prone to this phenomena. The results of our simulations confirm this fact, as we show in the manuscript. [ABSTRACT FROM AUTHOR]

We propose a novel paradigm for conflict resolution in multivehicle traffic systems, where a number of mobile agents move freely in a finite area, with each agent following a prespecified-motion profile. The key idea behind the proposed method is the tessellation of the underlying motion area in a number of cells and the treatment of these cells as resources that must be acquired by the mobile agents for the execution of their motion profiles, according to an appropriate resource allocation protocol. We capitalize upon the existing literature on the real-time management of sequential resource allocation systems (RASs) and develop such protocols that can formally guarantee the safe and live operation of the underlying traffic system, while they remain scalable with respect to the number of the moving agents. Collective past experience with the considered policies indicates that they also provide a pretty large coverage of the RAS behavioral space that characterizes its safe and live operation. Finally, we also establish that the aforementioned approach is applicable even in traffic systems where all vehicles must be in perpetual motion until their retirement. [ABSTRACT FROM PUBLISHER]

A mobile agent system is regarded as an attractive technology when developing distributed applications. However, mobility makes it more difficult to trace agents. It is also more complex for agents to communicate with each other in a reliable manner. Therefore, a reliable communication protocol is necessary to control and monitor mobile agents and deliver messages between them. In this paper, a new Reliable Communication Protocol (RCP) is proposed for a multiregion mobile agent computing environment. RCP is implemented on the ODDUGI mobile agent system. Analysis and evaluation show that RCP fulfills the following design goals: reliability, asynchrony, timeliness, location dependency, scalability, and communication cost. [ABSTRACT FROM AUTHOR]

The wireless mesh network (WMN) has recently emerged as a promising technology for next-generation wireless networking. In the WMN, it is crucial to support mobile users roaming around the network without service interruption. This consideration motivates us to develop an efficient fast handoff approach using distributed computing technology. Particularly, we propose a mobile agent (MA).based handoff architecture for the WMN, where each mesh client has an MA residing on its registered mesh router to handle the handoff signaling process. To guarantee quality of service (QoS) and achieve differentiated priorities during the handoff, we develop a proportional threshold structured optimal effective bandwidth (PTOEB) policy for call admission control (CAC) on the mesh router, as well as a genetic algorithm (GA)-based approximation approach for the heuristic solution. The simulation study shows that the proposed CAC scheme can obtain a satisfying tradeoff between differentiated priorities and the statistical effective bandwidth in a WMN handoff environment. [ABSTRACT FROM AUTHOR]

Various techniques and platforms have been introduced for the effective use of distributed computational resources when using specialized computational electromagnetics (CEM) simulation software for designing antennas. These techniques usually impose significant entry barriers to researchers, in the form of a steep learning curve for specialized application programming interfaces (APIs), or limited access to resources such as clusters or computational grids. The current paper discusses a sophisticated approach for alleviating these barriers, with the fusion of the programming paradigms of object- oriented programming and mobile agents. A case study concerning the development of a distributed Particle Swarm Optimization (PSO) platform - an increasingly popular algorithm within the antenna-research community - is thoroughly analyzed and presented as an example of data-level parallelism. Various aspects of computational efficiency in terms of scaling have been examined, in order to estimate the merits of the proposed approach. The aim of the analysis is to stress the advantages of the above-mentioned techniques for the effective loose coupling of CEM programs with distributed resources, demonstrating ease of application, improved scalability, and future expandability. [ABSTRACT FROM AUTHOR]

The article presents a study on the collective social strategies for the diffusion of multiagents. It highlights the use of two kinds of diffusions which are the collective insurgence, as well as the elite diffusions that are modelled through setting the variables in the formal framework. It explores the concurrent forms of collective diffusion, while social strategies are determined by other diffusion processes on other agents. It focuses on the spatial diffusion model assuming that all agents can be found in an Euclidian space wherein the social distances between agents can be measured.

WiMAX, a fourth-generation wireless-access technology, has made significant progress both in the standard forums and with wireless network carriers. To ensure service continuity to a legacy end user, it is important for a WiMAX mobile device to interwork with existing third-generation access networks before it is uniquely and ubiquitously deployed. This article addresses this issue and shows how interworking can be achieved with EVDO wireless-access technology, using mobile IP in a dual mode terminal. We present a network architecture solution and detailed call flows. [ABSTRACT FROM AUTHOR]

The growing demand for mobile Internet and wireless multimedia applications has motivated the development of broadband wireless-access technologies in recent years. Mobile WiMAX has enabled convergence of mobile and fixed broadband networks through a common wide-area radio-access technology and flexible network architecture. Since January 2007, the IEEE 802.16 Working Group has been developing a new amendment of the IEEE 802.16 standard (i.e., IEEE 802.16m) as an advanced air interface to meet the requirements of ITU-R/IMT-advanced for 4G systems, as well as for the next-generation mobile network operators. Depending on the available bandwidth and multi-antenna mode, the next-generation mobile WiMAX will be capable of over-the-air data-transfer rates in excess of 1 Gb/s and of supporting a wide range of high-quality and high-capacity IP-based services and applications while maintaining full backward compatibility with the existing mobile WiMAX systems to preserve investments and continuing to support first-generation products. This tutorial describes the prominent technical features of IEEE 802.16m and the potential for successful deployment of the next generation of mobile WiMAX in 2011+. [ABSTRACT FROM AUTHOR]

In this paper, the performance of the cooperative multiuser direct-sequence code-division multiple-access (DS-CDMA) system is analyzed in the asymptotic regime where both the spreading codes and the number of users grow unboundedly large with the same ratio. Assuming that each terminal is paired with another user which, in addition to transmitting its own data, estimates and relay the information transmitted from its partner, a simple approximate signal-to-interference-plus-noise ratio (SINR) expression is derived that is independent from the spreading codes and explicitly accounts for the effects of the multiple-access interference (MAI) and the relay noise. The so-obtained SINR expression is then computed based entirely on the available local information and without any knowledge about the interfering users. The results obtained above are then used to optimally design the cooperative system. In particular, it is shown how the amount of cooperation between each collaborating pair can be adjusted to simultaneously achieve a preassigned target SINR for both users. Based on the local information, the globally optimal amount of the relay power is obtained that maximizes the achieved SINR at the access point. It is shown that increasing the relay power does not necessarily result in improving the quality of reception at the access point and, to maximize each user's SINR, its relay power should be carefully adjusted based on the environmental parameters such as the interpartner channel link and the powers of MAI and the relay noise. The connection between the cooperative and the conventional multiuser systems is also studied and simulations are used to demonstrate the validity of the analytical results. [ABSTRACT FROM AUTHOR]

In this paper, we propose two different types of downlink scheduling scheme based on assembling the schemes of 1) the switch-and-examine scheduling in the network layer and 2) the joint adaptive modulation and output-threshold maximum ratio combining (OT-MRC) in the physical layer and, thus, attempt to find an efficient cross-layer access scheme to exploit the user diversity as well as the high spectral efficiency and the antenna diversity gain. We consider a multiuser environment in which each base station (BS) equipped with a single antenna attempts to communicate with each user equipped with an L-finger RAKE receiver based on switch-and-examine transmission (SET) as a user selection-scheduling scheme. We propose two different SETs, i.e., spectrally efficient SET and feedback load-efficient SET: We analyze the performance of our proposed schemes and compare them with the optimal scheduling scheme in terms of average spectral efficiency and average number of estimated paths per user to quantify the complexity. [ABSTRACT FROM AUTHOR]

In open heterogeneous context-aware pervasive computing systems, suitable context models and reasoning approaches are necessary to enable collaboration and distributed reasoning among agents. This paper proposes, develops, and demonstrates the following: 1) a novel context model and reasoning approach developed with concepts from the state-space model, which describes context and situations as geometrical structures in a multidimensional space; and 2) a context algebra based on the model, which enables distributed reasoning by merging and partitioning context models that represent different perspectives of computing entities over the object of reasoning. We show how merging and reconciling different points of view over context enhances the out- comes of reasoning about the context. We develop and evaluate our proposed algebraic operators and reasoning approaches with cases using real sensors and with simulations. We embed agents and mobile agents with these modeling and reasoning capabilities, thus facilitating context-aware and adaptive mobile agents operating in open pervasive environments. [ABSTRACT FROM AUTHOR]

As a recently emerging distributed computing paradigm, mobile-agent technology attracts great interests because of its salient merits. However, it also brings significant security concerns, among which the security problems between a mobile agent and its platforms are of primary importance. While protecting a platform (platform or host security) can benefit from the security measures in a traditional client-server system, protecting a mobile agent (mobile-agent or code security) has not been met in traditional client-server systems and is a new area emerging with mobile-agent technology. Mobile-agent security is also believed to be the most difficult in the security areas of a mobile-agent system. Several methods are proposed to provide protection or detection mechanisms for mobile-agent security. However, many of them either lack an intuitive formal approach to formally model and analyze the system or lack security consideration for mobility-the most distinct characteristic of a mobile agent. In this paper, we extended the original elementary object system (EOS), which applies object-oriented technology to Petri nets, in several aspects because the original EOS cannot fully support the features of mobile-agent system and security modeling. Based on the extended EOS (EEOS), we developed a formal model for a generic secure mobile-agent system. This model supports not only strong mobility but also secure mobility of a mobile agent. Mutual authentication between a mobile agent and its hosting platform is accomplished in this model. Meanwhile, a security mechanism is presented for the detection of malicious platform attacks to mobile-agent code or execution flow during the mobile- agent execution. Using an intuitively graphical formal method to model, simulate, and analyze a secure mobile-agent system distinguishes this paper from other works on mobile-agent security. This paper also introduces how to translate our EEOS model to a colored Petri net (CPN) model and presents the simulation of a sample mobile-agent system model in Design/CPN Different from the mathematical or theorem-proving analysis methods used by other mobile-agent system and mobility models, we used simulation-based analysis to verify several characteristics including boundedness, liveness, concurrence, and security of the system. Compared with other analysis methods, simulation-based analysis is generally more intuitive and more widely used in industry to solve real problems. [ABSTRACT FROM AUTHOR]

A wireless sensor network designed according to the sensor network with mobile agents (SENMA) architecture is engaged in a detection task, with a mobile agent (MA) that sequentially queries the network's nodes. The focus is on the effect of censoring: sensors respond to the query from the MA only if the local observations are deemed sufficiently informative; otherwise, they stay silent. Delivered data, if any, can be either unquantized or quantized to a single bit. The study is limited to shift-in-mean problems, involving two simple statistical hypotheses, where the noise distribution must be an even function but is otherwise arbitrary. Simple analytical relationships characterizing the tradeoff between the detection delay and the energy consumption of the network are derived, and examples of their applications are provided. [ABSTRACT FROM AUTHOR]

This paper addresses the connectedness issue in multiagent coordination, i.e., the problem of ensuring that a group of mobile agents stays connected while achieving some performance objective. In particular, we study the rendezvous and the formation control problems over dynamic interaction graphs, and by adding appropriate weights to the edges in the graphs, we guarantee that the graphs stay connected. [ABSTRACT FROM AUTHOR]

The article focuses on the use of service-oriented architecture (SOA) for smart home environment base on Open Services Gateway Initiative (OSGi) and mobile-agent (MA) technology. In a traditional smart home, problems like interacting with dynamic environment are existing. To address the problems, a service-oriented smart-home architecture on OSGi and MA technology was studied. The service-oriented mechanisms and MA technology were used to improve the interaction with home environment.

The article discusses the importance of trust management in distributed systems, such as peer-to-peer networks and mobile ad hoc networks. The authors look at the current research on trust management in distributed systems and explore some open research areas. The different models for describing trust management in distributed systems include public-key cryptography, the resurrecting duckling model, and the distributed trust model, all of which are described in the text. The article also discusses the properties of peer-to-peer distributed systems and mobile ad hoc systems, and then offer the best trust management models for both systems. Several tables are included in the text.

The article discusses the proposed system that can secure the integration of distributed medical data using mobile agent. The old virtual electronic patient record (VEPR) system architecture cannot handle the requirements and demands of modern health institutions, and it failed to provide security on the integration of distributed medical data. A new medical-information-gathering system was proposed to solve the deficiency of the old system. The new system is based on the widely used Java Agent Development Framework (JADE), a multi agent platform with the inter platform mobility service add, which will enable the transportation and integration of data among health institutions. It can securely gather and integrate distributed medical information using mobile agent technology.

In this article, the authors propose a Reliable Asynchronous Message Delivery (RAMD) protocol to address the problems facing mobile agents. RAMD places a blackboard in each region server for sharing information. It has a location-management procedure and a blackboard-based asynchronous message-delivery procedure. The protocol also relates message delivery with a mobile agent's migration, thus addressing the tracking and message-delivery problems. The authors implemented the RAMD protocol in the Oddugi system which is based on a mobile agent computing environment organized into many regions.

Today, remote control of instrumentation and remote measurement techniques represent a particularly interesting topic. Mature technologies are able to fully control devices and, in particular, help in remote measurement processes and calibrations. Now, attention has been moved to other questions, such as resource consumption, network availability, and client-server communication link. Mobile agent (MA) technology is capable of providing interesting solutions to the aforementioned problems, and an investigation concerning the possibility to migrate this technology to the measurement world is advisable. This paper reports some preliminary considerations and examples of applications of the MA technology in remote measurements. [ABSTRACT FROM AUTHOR]

The practical success of next-generation mobile systems such as 4G relies largely on its flexibility in providing adaptive and cost-effective services. Service discovery is an essential mechanism to achieve this goal. Based on the investigation of the existing service discovery protocols, this article proposes a new service discovery methodology for next-generation mobile systems: model-based service discovery or MBSD. By taking advantage of the Object Management Group (0MG) Model-Driven Architecture (MDA) technique, model-based service discovery (MBSD) can generate service description automatically and more precisely. Furthermore, if developed via MDA, the discovered services can be regenerated into their model format and as such facilitate the service re-engineering in a finer manner. The system architecture of MBSD and its operation are presented and implemented. The proposed methodology is validated via a mobile service scenario. [ABSTRACT FROM AUTHOR]

Digital TV is rolling on with full force recently. Within its capability of transmitting data along with the audiovisual contents, TV program providers can serve their viewers interactively, by offering the customized applications, which run at their viewers' set-top boxes. However, the traditional remote controller, with limited signal transmission distance and designed functionality, restricts the usage scope of applications on DTV within a specific space. In order to defeat this limitation, we devise a novel solution which allows mobile appliances in an IP network, e.g., mobile phones and laptops, to control set-top boxes. Through our special designed system collaborating with a media center responsible for complex multimedia tasks, (such as transcoding and broadcasting digital content), viewers can remotely command their own set-top boxes to record the DTV programs and to watch pre-recorded ones, respectively, by using numerous mobile appliances with the ability to access an IP network. Finally, the experiments proved that our implemented system is very efficient and effectively to control set-top boxes to execute multiple commands in the heterogenous environment combining the DTV network with the IP network. [ABSTRACT FROM AUTHOR]

This paper introduces a navigation method for a teleoperated mobile agent (or robot) moving in an unstructured environment that includes unknown obstacles and uneven terrain, based on a guided-navigation algorithm (GNA) and a rollover-prevention algorithm (RPA). Although the mobile agent is primarily driven by an operator at a remote site, it reacts autonomously for avoiding collision with obstacles and for preventing rollover when it suspects/detects possible collision or rollover. The autonomous reactive motion is normally unexpected, thus there exists the inconsistency between the intended motion and the controlled motion of the agent from the operator. A force-reflection technique utilizing a force-feedback joystick is developed to manipulate this inconsistency. To verify the feasibility and effectiveness of the proposed navigation method, experiments with the Robot for Hazardous Application-Double Tracks (ROBHAZ-DT) (actual mobile agent) are successfully carried out. [ABSTRACT FROM AUTHOR]

Wireless sensor networks are proposed to deliver in situ observations at low cost over long periods of time. Among numerous challenges faced while designing WSNs and protocols, maintaining connectivity and maximizing the network lifetime stand out as critical considerations. Mobile platforms equipped with communication devices can be leveraged to overcome these two problems. In this article existing proposals that use mobility in WSNs are summarized. Furthermore, a new approach to compute mobile platform trajectories is introduced. These solutions are also compared considering various metrics and design goals. [ABSTRACT FROM AUTHOR]

The article reports on the development of a foundation for autonomic workflow management in a grid environment. A model for dynamic fault tolerance technique selection was developed. This can be embedded into the workflow management system for a mobile agent. Current architecture for flexible fault tolerance in the grid was then augmented in order to allow the system to optimally configure its fault tolerant systems through an awareness of the computing environment.

The article discusses the framework for describing meta-adaptable systems that provide an accurate description of the behavior of intelligent entities. The illustrative example of the system which can be extended to address real situations as the development of software systems based on intelligent mobile agents has been explored.

This paper investigates a human walking behavior- based mobile robot control system. The Intelligent Space (iSpace) is a distributed sensory system, which is the background infrastructure to observe human walking in a limited area. The observation of human walking behavior is applied to train fuzzy-neural networks (FNN). The trained FNNs are applied to approximate the obstacle avoidance behavior of human walking. The paper introduces the iSpace and the mobile agents, which are mobile robots, utilizing the intelligence of the iSpace. The observed and trained human walking behaviors are applied to control the mobile agent in a human-robot shared environment. Experimental results demonstrate the effectiveness of the FNN-based control system. [ABSTRACT FROM AUTHOR]

This article extends specialized distributed problem solving (DPS) and multiagent systems (MASs) to a general MAS, such that an agent may make a trade-off between selfishness and unselfishness, thus adjusting its own personality and autonomy. Simulations of task allocation and resource assignment is MASs very the approach's advantages in terms of the spring nets' parallelism and higher convergence speed to an optimal solution. It was also shown how agents' autonomy and personality influence MAS performance. INSET: Elastic Nets for Sequencing Problems with Multiple Attributes..

A modern distributed industrial system, such as a power transmission system, consists of many sites distributed throughout a wide area. Each site contains a number of monitoring and control devices, also known as intelligent electronic devices, which perform various tasks including condition monitoring, control, and protection. However, apart from dedicated links to the control center for control purposes, substations are often connected by networks with relatively low bandwidth, which makes remote access to these devices for control or monitoring relatively difficult. Therefore, we propose the use of mobile agents for remote access to devices. In this paper, the advantages and disadvantages of the use of mobile agents are evaluated by means of a theoretical model and a series of experiments. The results suggest that for networks with high latency mobile agents may provide performance improvements over more conventional client-server systems. [ABSTRACT FROM AUTHOR]

This paper proposes a methodological approach for the performance analysis of Web-based searching applications on the Internet. It specifically investigates the behavior of the Client/Server (C/S), Remote-Evaluation (REV) and Mobile-Agent (MA) communication paradigms and describes how Petri-net models can be developed to derive performance indices which can help the designer to improve the efficiency of his distributed applications. Our purpose is that of identifying a set of models that can help to understand the environmental situations in which such paradigms should be preferred or combined in order to optimize the performances of a distributed system. In particular, we propose a modeling technique applied to an Information Retrieval application on the World Wide Web. An analytical evaluation through the solution of non-Markovian Petri-net models is provided, which allows us to identify the main parameters, as well as the way they interact, to be taken into consideration when distributed applications are to be designed. An experimental environment is also studied in order to obtain real measurements used to validate the analytical models. [ABSTRACT FROM AUTHOR]

There has been a surge of interest in the delivery of personalized information to users (e.g., personalized stocks or travel information), particularly as mobile users with limited terminal device capabilities increasingly desire updated and targeted information in real time. When the number of information recipients is large and there is sufficient commonality in their interests, as is often the case, lP multicast is an efficient way of delivering the information. However, IP multicast services do not consider the structure and semantics of the information in the multicast process. We propose the use of Content-Based Multicast (CBM) where extra content filtering is performed at the interior nodes of the IP multicast tree; this will reduce network bandwidth usage and delivery delay, as well as the computation required at the sources and sinks. In this paper, we evaluate the situations in which CBM is advantageous. The benefits of CBM depend critically upon how well filters are placed at interior nodes of the IP multicast tree and the costs depend upon those introduced by filters themselves. Further, we consider the benefits of allowing the filters to be mobile so as to respond to user mobility or changes in user interests and the corresponding costs of filter mobility. The criterion that we consider is the total network bandwidth utilization. For this criterion, we develop an optimal filter placement algorithm, as well as a heuristic that executes faster than the optimal algorithm. We evaluate the algorithms by means of simulation experiments. Our results indicate that filters can be effective in substantially reducing bandwidth. We also find filter mobility is worthwhile if there is marked large-scale user mobility. We conclude with suggestions for further work. [ABSTRACT FROM AUTHOR]