Multi-Agents

This paper presents some results in the intersection of three technological fields: e-learning, multiagent systems, and standards to improve the development of secure systems. There is a consensus that security is a critical issue for distributed, highly interactive and open learning environments. While a lot of effort in the e-learning domain has been put into delivering infrastructure and providing content, security issues have hardly ever been considered. Agent-oriented methodologies may bring benefits to the conception of multiagent systems, since they gradually are incorporating specifications for general security mechanisms (FIPA standards). Concerning the specification of security requirements for e-learning environments, extended formalisms (such as security use cases) appear as proper modeling tools. The topics covered by this paper converge to the implementation of a multiagent platform (the PMA3), which constitutes an open distributed infrastructure addressing important security issues. PMA3 has been used in the development of elearning environments. The paper concludes with an outlook to ongoing research efforts related to security requirements for e-learning applications.

The resource accessibility problem in a cooperative learning environment can be stated as how both teachers and students can gain access to resources (information and hardware devices) not only from remote locations, but also from the classroom. In this paper we present a task model (TMo) that describes the services for a Resource Management System (RMS) to solve such problem. The model illustrates how to: 1) manage course information, and 2) operate hardware devices. As a modelling methodology we have resorted to CommonKADS.

Vehicular ad hoc networks (VANETs) provide a robust infrastructure for intelligent transportation system (ITS) applications. VANET communication involves vehicle-to-vehicle and vehicle-to-infrastructure connections, primarily with roadside units (RSUs). Analyzing cognitive radio (CR)-VANET studies revealed two key performance issues: high energy consumption and latency. To address these challenges, we propose a novel approach: link stability and mobility prediction-based clustered CR-VANETs, known as LMCCR-VANET. LMCCR-VANET consists of four main components: CR-VANET construction, clustering model, speed-based mobility prediction, and link-based multipath routing. Initially, we establish cluster-based CR-VANETs to analyze and mitigate spectrum scarcity and power utilization problems in VANETs. Mobility prediction evaluates vehicle speed variations and predictions. Finally, employing link stabilitybased multipath routing (LSMR) in conjunction with the fuzzy interference model and ad hoc on-demand multipath distance vector (AOMDV) routing protocol ensures stable and efficient routing. Experimental results showcase the superiority of LMCCR-VANET. It exhibits enhanced energy efficiency, delivery rates, reduced energy consumption, end-to-end latency, and routing overhead when compared to recent works such as SCCR-VANET, CFCR-VANET, and MMCR-VANET.

In the Dynamic Content Management (DCM) system one focuses on removing the tight association between learning material to specific courses. In this system one defines a conceptual atomic unit of knowledge and builds the material by the organization of these knowledge elements from a repository. The system allows an educator to create an arbitrary collection of knowledge elements, tag them with meta-information as a single unit and link the unit with previously saved and similar aggregations. The DCM system uses idea of Concept Maps to model the relationships between the knowledge elements that can be created by the instructor or the educator. A pilot system has been implemented based on a client-server architecture. The server is programmed in Python and the client as a Java application made available through Java Web Start. In the paper we also present different design and implementation aspects of a future Multi-Agent System (MAS) based on the DCM model. The implementation of such a model of e-learning is based on JADE-a FIPA compliant platform.

Objectives: To propose a suitable protocol that is secured and efficient for data transmission in Vehicular Adhoc Networks (VANET) environment. Methods/Statistical Analysis: The main challenge in VANET is to protect valuable information from the users. However there are many malicious vehicles that affect the system. To overcome this problem, the Secure and Intelligent routing (SIR) protocol is used that will transmit the data in shortest path through the authenticated vehicles. The proposed method makes use of message transmission, link connectivity and vehicle positioning to forward the data to the destination. Sending the data through the QoS based optimized path will enhance the performance of the system. Hence the proposed Enhanced Secure and intelligent routing (ESIR) protocol is QoS enabled and optimized. The QoS metrics taken into concern are delay, network load and distance with minimum number of hops. Particle Swarm Optimization (PSO) algorithm used for optimization in the proposed work takes one main parameter into concern; it is distance with minimum number of hops. Findings: The proposed technique is compared with the existing SIR protocol in terms of throughput, delay, packet delivery ratio, residual energy levels and packet drop. The results obtained show that the proposed technique serves as an efficient routing protocol for VANET environment providing a reliable and robust service.

This chapter analyzes the process of forming a coalition within a corporate network. The objective of the partner companies is to create a multi-stage manufacturing system, which generates a chain of increased value from raw materials to end-user market. This process is studied by cooperative game theory, through the key problems of maximizing the total profit and distributing it among the members of the coalition. To construct a pay-off policy that is both stable and fair, the study proposes to represent the productive resources of the firms not only by their capacity, but also by the WIP generated by product flows. The proposed profit sharing rule is then constructed from the dual of the profit maximization problem. It is both efficient and rational, with more fairness than the Owen set policy of classical Linear Production Games.

A vehicular ad-hoc network (VANET) is a set of intelligent vehicles that interact without any fixed infrastructure. Data transmission between each transmitter/receiver pair is accomplished using routing protocols. However, communication over the VANET is vulnerable to malicious attacks, because of the unavailability of fixed infrastructure and wireless communication. In this paper, the trust based multi objective honey badger algorithm (TMOHBA) is proposed to achieve secure routing over the VANET. The TMOHBA is optimized by incorporating different cost functions, namely, trust, end to end delay (EED), routing overhead, energy, and distance. The developed secure route discovery using the TMOHBA is used to improve the robustness against the malicious attacks, for increasing the data delivery. Moreover, the shortest path discovery is used to minimize the delay while improving the security of VANET. The TMOHBA method is evaluated using the packet delivery ratio (PDR), throughput and EED. Existing researches such as hybrid enhanced glowworm swarm optimization (HEGSO) and ad-hoc on-demand distance vector based secure protocol (AODV-SP) are used to evaluate the TMOHBA method. The PDR of the TMOHBA method for 10 malicious attacks is 90.6446% which is higher when compared to the HEGSO and AODV-SP.

A vehicular ad-hoc network (VANET) is a set of intelligent vehicles that interact without any fixed infrastructure. Data transmission between each transmitter/receiver pair is accomplished using routing protocols. However, communication over the VANET is vulnerable to malicious attacks, because of the unavailability of fixed infrastructure and wireless communication. In this paper, the trust based multi objective honey badger algorithm (TMOHBA) is proposed to achieve secure routing over the VANET. The TMOHBA is optimized by incorporating different cost functions, namely, trust, end to end delay (EED), routing overhead, energy, and distance. The developed secure route discovery using the TMOHBA is used to improve the robustness against the malicious attacks, for increasing the data delivery. Moreover, the shortest path discovery is used to minimize the delay while improving the security of VANET. The TMOHBA method is evaluated using the packet delivery ratio (PDR), throughput and EED. Existing researches such as hybrid enhanced glowworm swarm optimization (HEGSO) and ad-hoc on-demand distance vector based secure protocol (AODV-SP) are used to evaluate the TMOHBA method. The PDR of the TMOHBA method for 10 malicious attacks is 90.6446% which is higher when compared to the HEGSO and AODV-SP.

A vehicular ad-hoc network (VANET) is a set of intelligent vehicles that interact without any fixed infrastructure. Data transmission between each transmitter/receiver pair is accomplished using routing protocols. However, communication over the VANET is vulnerable to malicious attacks, because of the unavailability of fixed infrastructure and wireless communication. In this paper, the trust based multi objective honey badger algorithm (TMOHBA) is proposed to achieve secure routing over the VANET. The TMOHBA is optimized by incorporating different cost functions, namely, trust, end to end delay (EED), routing overhead, energy, and distance. The developed secure route discovery using the TMOHBA is used to improve the robustness against the malicious attacks, for increasing the data delivery. Moreover, the shortest path discovery is used to minimize the delay while improving the security of VANET. The TMOHBA method is evaluated using the packet delivery ratio (PDR), throughput and EED...

Intelligent Transport System (ITS) is a transport system that uses communicating technologies such as cellular network communication, digital video broadcasting and adhoc wireless communication to link people on the road, vehicles with aim of solving various traffic related issues. Vehicle to infrastructure (V2I) communication is an important research area to develop cooperative self-driving support system using DSRC technology. V2I develops an environment friendly system that also accelerates the fuel efficiency by establishing high quality links between vehicles to roadside infrastructure. It is a system to prevent and help drivers to overlooking or missing the red lights at junctions. V2I system along the road side and intersections continuously transmit the traffic signal information to vehicles by warning the driver about red lights and thus help us to prevent road rule violations. ITS helps to prevent drivers' oversight about signals right/left turn collision avoidance and...

The VANET is a type of network that can be built randomly, quickly and temporarily without any standard infrastructure. In VANET, routing of data is an interesting and challenging task because of the high mobility. Therefore, the routing algorithm for VANETs is an imperative issue, particularly in vehicle to vehicle communication. This paper proposes a multipath routing algorithm for VANET named energy and velocity based multipath routing protocol (EVMRP) based on available bandwidth, residual energy and relative velocity. The most important point of the proposed algorithm is setting the CWmax as the available bandwidth of the path. The proposed algorithm is tested on the QoS parameters like end-to-end delay, throughput and packet loss. The results clearly indicate that the proposed algorithm, EVMRP outperforms when compared to the legacy systems like AOMDV.

Currently, increase of CO 2 emissions in the city areas is due to industrial pollution, burning of fuels, deforestation, and excessive vehicle movement. For environmental safety, regular monitoring of CO 2 level is needed in the city areas. The main objective of this research is to localize the high CO 2 zones in the city areas using UVANETs. Vehicles in the city areas are used as the resources to collect and monitor the CO 2 levels. After the zone localization, the location (high CO 2 zone) information is sent to the information center using the proposed routing scheme through the vehicles to take possible actions in emergency. To the best of our knowledge no such work has been proposed to localize the high CO 2 zones in the city areas using UVANETs. For performance evaluation, this method is tested in a small UVANET prototype developed in indoor environment.

Vehicular ad hoc networks (VANETs) is an emerging technology which has received lot of attention due to its potential to improve vehicle and road safety, traffic control, efficiency as well as convenience for users. VANET is a sub category of mobile ad hoc network (MANET). A lot of research in VANET is done on routing, broadcasting, Quality of Security (QoS) and security. This paper proposes a novel path planning algorithm for efficient routing. The proposed system will traditionally distribute the work load over alternate paths in order to avoid congestion and reduce travel cost. It will also ensures reliable routing with less bandwidth requirement and high packet delivery ratio as it avoids packet loss. VANET may be affected by attacks on routing leading to altering messages and routes which will affect QoS parameters. The proposed algorithm will deal with providing security measures over the routing process. Therefore we obtain routing algorithm subject to multiple QoS constrains...

This chapter analyzes the process of forming a coalition within a corporate network. The objective of the partner companies is to create a multistage manufacturing system, which generates a chain of increased value from raw materials to end-user market. This process is studied by cooperative game theory, through the key problems of maximizing the total profit and distributing it among the members of the coalition. To construct a pay-off policy that is both stable and fair, the study proposes to represent the productive resources of the firms not only by their capacity, but also by the WIP generated by product flows. The proposed profit sharing rule is then constructed from the dual of the profit maximization problem. It is both efficient and rational, with more fairness than the Owen set policy of classical Linear Production Games.

As the number of handicapped people increases worldwide, Intelligent Wheelchairs (IW) are becoming the solution to enable a higher degree of independence for wheelchair users. In addition, IW Projects relevance is increasing, mainly in the fields of robotics and safety-related systems due to their inherent and still unresolved problems related with environment uncertainty, safe communications and collaboration methodologies. This paper describes the development of new communication system, based on multi-agent systems (MAS) and motivated by Intelligent Wheelchair systems. It uses a message-oriented paradigm as a mean for faulttolerant communications in open transmission systems as well as a facilitator for entity collaboration. It provides an overview of the related work in the area, the background and the main constraints to system development, contextualized an IW development project. The results achieved enable us to conclude on the effectiveness and adequacy of the proposed communication model to the field of mobile robots, as well as to conclude that it may outperform JADE in several test scenarios.

A control system with the capabilities to combine heterogeneous control systems or processes into a uniform homogeneous environment is discussed. This dynamically extensible system is an example of the software system at the agent level of abstraction. This level of abstraction considers agents as atomic entities that communicate to implement the functionality of the control system. Agents' engineering aspects are addressed by adopting the domain independent software standard, formulated by FIPA. Jade core Java classes are used as a FIPA specification implementation. A special, lightweight, XML RDFS based, control oriented, ontology markup language is developed to standardize the description of the arbitrary control system data processor. Control processes, described in this language, are integrated into the global system at runtime, without actual programming. Fault tolerance and recovery issues are also addressed.

Intelligent Transport System (ITS) is a transport system that uses communicating technologies such as cellular network communication, digital video broadcasting and adhoc wireless communication to link people on the road, vehicles with aim of solving various traffic related issues. Vehicle to infrastructure (V2I) communication is an important research area to develop cooperative self-driving support system using DSRC technology. V2I develops an environment friendly system that also accelerates the fuel efficiency by establishing high quality links between vehicles to roadside infrastructure. It is a system to prevent and help drivers to overlooking or missing the red lights at junctions. V2I system along the road side and intersections continuously transmit the traffic signal information to vehicles by warning the driver about red lights and thus help us to prevent road rule violations. ITS helps to prevent drivers' oversight about signals right/left turn collision avoidance and...

This paper focuses on the decentralized systems that use the revenue-sharing and cost-sharing contracts as coordination mechanisms. We consider a grand-coalition N with finite players, who agree to cooperate by undertaking part of the system's cost individually, while the remaining costs C and revenues R are shared properly, in order to allocate the system's profits and risks equally among them. We use cooperative game theory, in order to examine the possible coalitions of players and to estimate the finite set of solutions, with which the system's profits and risks are allocated equally among all players. Specifically, each system's solution consists of a pair of vectors r, c Є N , with which all player profits are normally distributed with equal mean values and variances. Moreover, we introduce a code that can be used for the computation of the precise number of possible solutions.

Abstract—This paper examines the feasibility stage of Public Private Partnerships (PPPs) and specifically the evaluation of the public sector's contribution in the project's funding scheme. We focus on those PPP projects, where the initial investment is funded by both public and private parts and revenues are shared between the two. Generally, a basic step of a PPP project appraisal is the risk analysis process, where the probability that the partners' evaluation indicators will take positive values is calculated. Herein, a risk based ...

Simulation is one approach to analyze and model the real world complex problems. Multi-agent based systems provide a platform to develop simulations based on the concept of agent-oriented programming. In multi-agent systems, the local interaction between agents contributes to the emergence of the global phenomena by getting the result of the simulation runs.

The autonomous cars are considered as a tremendous disruptive innovation in the coming years. They enable a driving automation system to replace human drivers to control the vehicle with better recognition, decision and driving skills and ultimately enhance the road users' experience and traffic safety. They can communicate with other cars as they are ready with the Vehicle to Vehicle (V2V) communication technology based on Vehicular Ad hoc Networks (VANETs). One of the objectives of V2V communication is for the safety of all road users. Adequate reliability of routing protocol is subject of concern and must be taken into account to reach an immense standard of road safety accurately and timely. Having no reliability the critical road safety messages will be useless; consequently, the accident that might happen is unable to prevent or avoid. The purpose of this research is to investigate and analyze the quantitative measure of reliability. The reliabilities of a reactive single-path AODV and a multipath AOMDV routing protocols that comply with road safety requirements in various traffic conditions are studied. The traffic conditions that may impact the internetworking of autonomous cars include node density, size of road area and speed of the nodes. The methods used in this study are based on simulations by using Network Simulator version-2 (NS2) as a network simulator and Simulation of Urban Mobility (SUMO) as a mobility simulator. The simulation results show that both routing protocols, a single-path AODV and a multi-path AOMDV, satisfy the road safety requirements in some conditions. AODV is better in packet delivery, whereas AOMDV has a better performance on average end to end delay. This study is expected to contribute to the determination of the appropriate protocol for use in road safety applications under certain traffic conditions. In conclusion, the reliability of routing protocol is an essential factor to consider in the operation of VANET-based autonomous cars so that the safety and comfort of road users can be guaranteed.

Agent-based technologies in production control systems could facilitate seamless reconfiguration and integration of mechatronic devices/modules into systems. Advances in embedded controllers which are continuously improving computational capabilities allow for software modularization and distribution of decisions. Agent platforms running on embedded controllers could hide the complexity of bootstrap and communication. Therefore, it is important to investigate the messaging performance of the agents whose main motivation is the resource allocation in manufacturing systems (i.e., conveyor system). The tests were implemented using the FIPA-compliant JADE-LEAP agent platform. Agent containers were distributed through networked embedded controllers, and agents were communicating using request and contract-net FIPA interaction protocols. The test scenarios are organized in intercontainer and intracontainer communications. The work shows the messaging performance for the different test scenarios using both interaction protocols.

The MAELIA project is developing an agent-based modeling and simulation platform to study the environmental, economic and social impacts of various regulations regarding water use and water management in combination with climate change. It is applied to the case of the French Adour-Garonne Basin, which is the most concerned in France by water scarcity during the low-water period. An integrated approach has been chosen to model this social-ecological system: the model combines spatiotemporal models of ecologic (e.g. rainfall and temperature changes, water flow and plant growth) and socioeconomic (e.g. farmer decision-making process, management of low-water flow, demography, land use and land cover changes) processes and sub-models of cognitive sharing among agents (e.g. weather forecast, normative constraints on behaviors).

I would like to express my deep gratitude toward my advisor, Professor Luiz Albini, for all the guidance he offered throughout the research that led to this dissertation. His frequent ideas and suggestions were what inspired me to pursue knowledge and be encouraged to find solutions to problems that are far from simple. Furthermore, I would like to thank Professor Eduardo Todt, who has helped me in ways beyond this dissertation, and my fellow students, Eric, Nelson and Ivan, who always brought interesting conversations. I would also like to thank my friends, in particular Taiane, Cainã, Douglas, Lucas and Giancarlo for bringing joy to my life for many years. Perhaps most importantly, I would like to thank my parents, Edison and Lizmari, who supported me throughout the whole process and always reminded me that I was on a path worth pursuing, as well as my grandmother Glacial and everyone in my family. Palavras-chave: redes veiculares, gerenciamento de confiança, identificação de nós maliciosos.

This paper presents vehicle-to-vehicle telescreen (VVT) and a multicast scheme to disseminate digital signage multimedia services to vehicular ad hoc networks (VANETs). Multimedia dissemination in VANETs is challenging because of the high packet losses (PLs), delays and longer disconnection times, which degrade the network quality of service (QoS) and user quality of experience (QoE). To reduce the PLs and delays, most existing multimedia multicast schemes in VANETs primarily select routes based on longer route expiration times (RET) or lowest path delays. The RET-based schemes suffer less from PLs when there are fewer active multicastings in the network. When the number of active multicastings increases, delay-based schemes suffer less from PLs comparatively. This tradeoff implies to design an adaptive mechanism by mutually complementing the RET-based and delaybased schemes to reduce PLs and delays. In this paper, we propose a multicriteria adaptive opportunistic treecast routing protocol (MAOTRP), which adapts the route selection mechanism according to active multicastings for efficient multimedia dissemination in VVT. The MAOTRP adjusts the weights of route selection parameters, including RET and delays, by considering their contribution in improving packet delivery ratio. MAOTRP extends a treebased multicast protocol to provide robustness through alternate routes for link failures to reduce PLs. Through several experimental evaluations, we show that the proposed dissemination scheme improves QoS and QoE, and reduces the average disconnection time.

The vehicular ad-hoc network now a day’s growing field of research, due its infrastructure or rapidly change topology. VANET is sub part of MANET and combination of nodes and roadside units. VANET uses high movable nodes as compared to MANET. VANET provide wireless communication among vehicles and vehicle to roadside unit for sharing information and safety purpose of drivers and passengers. There are various malicious activities performed in network like bogus information attack, ID discloser, sybil attack etc. All these attacks try to distract drivers. In this paper we work on Dos attack in AODV routing protocol. When malicious node sends fake requests frequently to other nodes it creates a blockage in network then node is not able to respond to other nodes. In this paper Artificial Neural Network in VANET is used; so neural network helps to train the node and uses the back propagation and adjust the weights. For the identification of malicious node SOM classifier is used. SOM obse...

Vehicular ad hoc network (VANET) is known as an essential factor of smart Transportation systems. The key benefit of VANET communication is noticed in dynamic protection systems, which objective to enhance security of travelers by exchanging caution messages between automobiles. Other applications and personal services are also allowed in order to lower the cost and to promote VANET exploitation. To effectively set up VANET, security is one of the main challenges that must be tackled. Another important concern is scalability is a serious issue for a network designer how to maintain stable communication and services in VANET. Extremely dynamic environment of VANETs seems it difficult. This paper proposed a more secure and stable cluster scheme for VANETs that uses drop ratio to categorize nodes as malicious. Here also proposed an entropy-based WCA (EWCA) cluster maintained scheme which can handle the stability of the vehicular network.

Modernization in field of technology is characterized by usage of wireless gadgets, and is no far from transportation field through the deployment of VANET (Vehicular Ad Hoc Network) permitting modern users for better coverage of their travelling distance. VANET is valuable approach that allows for accomplishment of better performance and assuring safe transportation system in prospect. VANET, encircle vehicles, as mobile nodes connecting and communicating among themselves and with access points (roadside units) establishing a network. Amplification in use of VANET stimulates voluminous applications such as road topology, emergency information, electronic toll collection and many more. Expansion and advancement in VANET, engenders numerous applications as real-time traffic, electronic toll collection and surrounding road conditions. In this paper, R-optimal paths technique have been undertaken to ensue real-time communication between nodes. When any node wants to establish path to d...

As the number of handicapped people increases worldwide, Intelligent Wheelchairs (IW) are becoming the solution to enable a higher degree of independence for wheelchair users. In addition, IW Projects relevance is increasing, mainly in the fields of robotics and safety-related systems due to their inherent and still unresolved problems related with environment uncertainty, safe communications and collaboration methodologies. This paper describes the development of new communication system, based on multi-agent systems (MAS) and motivated by Intelligent Wheelchair systems. It uses a message-oriented paradigm as a mean for faulttolerant communications in open transmission systems as well as a facilitator for entity collaboration. It provides an overview of the related work in the area, the background and the main constraints to system development, contextualized an IW development project. The results achieved enable us to conclude on the effectiveness and adequacy of the proposed communication model to the field of mobile robots, as well as to conclude that it may outperform JADE in several test scenarios.

This paper introduces a Reliable Routing Protocol (R 2 P) for Vehicular Ad-hoc Networks (VANETs), which divides the network into overlapping zones. For each zone, a special node is promoted to be the Master Node (MN), which maintains an up-to-date routing boards for inter/intra-zone communication. R 2 P depends on two types of boards, namely; Internal Routing Board (IRB) and External Routing Board (ERB). Two types of IRB are used, namely; Zone Routing Board (ZRB) that is maintained by MNs, and Private Routing Board (PRB) that is maintained by each network node. Both ZRB and PRB register routes among zone nodes, while ERB, which is maintained by MN, registers available gateways to neighboring zones. R 2 P employs a special route discovery mechanism to discover available routes to the destination, and then elects the most reliable route. It has been compared against the recent VANET's routing protocols. Experimental results have shown that R 2 P outperforms the others.

I. INTRODUCTION A wireless ad hoc network (WANET) is a decentralized type of wireless network. It is called as ad hoc because it does not rely on a pre-existing infrastructure, such as routers in wired networks or access points in managed wireless networks. In this network, each node participates in routing by forwarding data for other nodes, so the determination of which nodes forward data is made dynamically on the basis of network connectivity. Ad hoc networks also use flooding for forwarding data in addition with the classic routing [1]. There are many different types of Ad-hoc network presents. Some of them are briefly discussed here.

The emergence of smart cities and the need to use intelligent transportation systems has led to an increased reliance on vehicle ad hoc networks (VANET). The topology of VANET is highly dynamic, which results in a short effective routing time. This paper presents  a two-stage algorithm to select a route that can sustain communication between vehicles for as long as possible while taking into account the variables that affect the VANET topology. The first stage uses Skellam distribution model to assess the connectivity probability of paths in ‎a 2d road network based on traffic-flow and the number of vehicles ‎joining and leaving the ‎network,  accordingly, the path with the highest connectivity is chosen. In the second stage, the control packets sent only to vehicles on the selected path to detect routes between source and destination, thus reducing the overhead of control packets and increasing network stability. ‎ the algorithm adopts the principle of global evaluation to ‎estimat...

In this paper we present a teacher interface for a computer supported educational system that we are developing. This interface was developed over a PDA with wireless network connectivity to be carried by the teacher into the classroom. The first prototype implemented an interface with a virtual keyboard and mouse in order to remotely manage the classroom server and its peripherals. Additionally other features were included, such a remote video projector control and an agenda application. However, users had problems with regard to direct text introduction and mouse sensibility. Knowledge of the domain was acquired from experts in the field of education, and as a result, a new set of project requirements were defined and a second version of the interface has been developed. Its task-oriented design improves usability through minimizing the need for a virtual keyboard and mouse utilization. This system is currently in use in two classrooms in our university.

In this paper we present a teacher interface for a computer supported educational system that we are developing. This interface was developed over a PDA with wireless network connectivity to be carried by the teacher into the classroom. The first prototype implemented an interface with a virtual keyboard and mouse in order to remotely manage the classroom server and its peripherals. Additionally other features were included, such a remote video projector control and an agenda application. However, users had problems with regard to direct text introduction and mouse sensibility. Knowledge of the domain was acquired from experts in the field of education, and as a result, a new set of project requirements were defined and a second version of the interface has been developed. Its task-oriented design improves usability through minimizing the need for a virtual keyboard and mouse utilization. This system is currently in use in two classrooms in our university.

Objectives: To propose a suitable protocol that is secured and efficient for data transmission in Vehicular Adhoc Networks (VANET) environment. Methods/Statistical Analysis: The main challenge in VANET is to protect valuable information from the users. However there are many malicious vehicles that affect the system. To overcome this problem, the Secure and Intelligent routing (SIR) protocol is used that will transmit the data in shortest path through the authenticated vehicles. The proposed method makes use of message transmission, link connectivity and vehicle positioning to forward the data to the destination. Sending the data through the QoS based optimized path will enhance the performance of the system. Hence the proposed Enhanced Secure and intelligent routing (ESIR) protocol is QoS enabled and optimized. The QoS metrics taken into concern are delay, network load and distance with minimum number of hops. Particle Swarm Optimization (PSO) algorithm used for optimization in the proposed work takes one main parameter into concern; it is distance with minimum number of hops. Findings: The proposed technique is compared with the existing SIR protocol in terms of throughput, delay, packet delivery ratio, residual energy levels and packet drop. The results obtained show that the proposed technique serves as an efficient routing protocol for VANET environment providing a reliable and robust service.

A Vehicular Ad-Hoc Network, or VANET, is a form of Mobile ad-hoc network, to provide communications among nearby vehicles and between vehicles and nearby fixed equipment (Base Stations) via radio waves. These have similar characteristics as mobile ad hoc networks, often in the form of multi-hop networks. Due to the high mobility of nodes network topology changes occur frequently. All nodes share the same channel leading to congestion in very dense networks. One important property that characterizes VANETs is that they are self-organizing, self-creating, and self administering and decentralized systems. This paper proposes detection and elimination of misbehaving nodes in VANETs using mobile agents. Mobile agents are employed for each node, for the collection of information of neighbours and to find the route from source to the destination. To find the malicious nodes among the intermediate nodes, mobility and power ratio of the intermediate nodes are continuously monitored with the ...

The Internet of Things (IoT) is a world of connected networks and modern technology devices, among them vehicular networks considered more challenging due to high speed and network dynamics. Future trends in IoT allow these inter networks to share information. Also, the previous security solutions to vehicular IoT (VIoT) much emphasize on privacy protection and security related issues using public keys infrastructure. However, the primary concern about efficient trust assessment, authorized users malfunctioning, and secure information dissemination in vehicular wireless networks have not been explored. To cope with these challenges, we propose a trust enhanced on-demand routing (TER) scheme, which adopts TrustWalker (TW) algorithm for efficient trust assessment and route search technique in VIoT. TER comprised of novel three-valued subjective logic (3VSL), TW algorithm, and ad hoc on-demand distance vector (AODV) routing protocol. The simulated results validate the accuracy of the p...

Vehicular Ad hoc Networks (VANET) play an important role in future on road Vehicle-to-Vehicle communication systems and related applications like self-organizing, acquiring traffic information using sensors and disseminating it to the nearby vehicles, which are based on broadcast/geocast transmission schemes. It is a challenging task to manage networks in a dynamic environment due to the characteristic of high mobility rate, high relative speed, different driver behaviors and unpredictable link failure occurrences. One of the main criteria in VANETs that has attracted the researchers' consideration is congestion control. Congestion is a major problem all over world, resulting in wastage of valuable time and money. In this paper, we propose multi agent based congestion control scheme, which intelligently acquires the status of the neighboring node information and decides the congestion free path for the safe delivery of packets. Multi agent scheme consists of set of static and mobile agents. Proposed approach guarantees the reliability and timely delivery of messages. Multi agent based scheme exhibits better bandwidth usage and packet delivery ratio and minimizes the latency

The EUME project is intended to develop an Intelligent Learning Management System (ILMS) with the aim to improve the quality of traditional teaching strategies as well as to facilitate the implementation of new learning methodologies. At this project stage, we have developed a knowledge model of the educational domain, designed a component-based software architecture, and implemented the second cycle of the construction plan. In this paper an overview of the main results achieved so far is presented.

Multi-agent systems (MAS) are a software development paradigm suitable for dynamic and complex application domains. A noteworthy feature of many agent systems is the ability of agent migration. Agent migration procedure consists of two distinct steps; code migration and agent state migration. Migration of agent's state is a process of serializing agent's state and de-serializing it at destination. Migration of code is a more complex issue, due to heterogeneous nature of operating systems which can host agent platforms. A common approach is to implement an agent system in on a platform which is agnostic to the operating system and hardware. A popular language and a platform for such task is Java, which is also the language of choice for the Android platform. Byte-codes of Java virtual machine (JVM) and Android Dalvik virtual machine are not interchangeable. The paper presents agent platform JADE, agent mobility implementation and class loading mechanism in Android. Analysis o...

This paper performs a survey on the state of the art in the security and access controls mechanisms employed by multiagent systems as a form of data transaction, with special emphasis on their security threats and how these issues are currently being tackled for multi-agent systems. In this paper we provide a brief summary of current approaches and provide comments on their relevance, implementation and safety assumptions behind their safe operation on real systems with sensitive data. We also take special notice on the security issues approached by each one of the analysed proposals and the sometimes ingenious ways proposed by different authors to solve them. We also pay special attention to issues related with the authentication, confidentiality, integrity and access control mechanisms employed to minimise security incidents. Nowadays multi-agent systems are increasingly being researched and deployed to solve complex interoperability issues that normally occur between different institutions. The final result of this survey is a summary aggregation of knowledge about security and access control practises for multi agent models and implementations.

The MAELIA project is developing an agent-based modeling and simulation platform to study the environmental, economic and social impacts of various regulations regarding water use and water management in combination with climate change. It is applied to the case of the French Adour-Garonne Basin, which is the most concerned in France by water scarcity during the lowwater period. An integrated approach has been chosen to model this socialecological system: the model combines spatiotemporal models of ecologic (e.g. rainfall and temperature changes, water flow and plant growth) and socioeconomic (e.g. farmer decision-making process, management of low-water flow, demography, land use and land cover changes) processes and sub-models of cognitive sharing among agents (e.g. weather forecast, normative constraints on behaviors).

Politicas públicas de água têm grande influência sobre diferentes tipos de recursos (recursos hídricos, da terra e do solo; infraestrutura e instalações prediais; recursos financeiros; informação e conhecimento ambiental; etc.). Elas atuam sobre agentes individuais ou coletivos (usuários, gestores, empresas públicas ou privadas, associações, etc.), assim como como regras e normas de comportamento que estes atores são os destinatários ou agentes. Sistemas complexos, se for o caso, essas políticas têm vários tipos de efeitos, esperados e inesperados, os efeitos diretos e indiretos, sociais, econômicos, ambientais e eco-sistêmica. O atual desenvolvimento de plataformas multi-agente abre uma nova área para a definição, concepção, implementação e monitoramento da gestão da água, produzindo simulações ex ante do impacto das medidas que promovem políticas públicas de água e da evolução provável da situação sócio-HYDROSYSTEM em causa. Aqui vamos dar uma visão geral das novas oportunidades de modelagem de política da água e avaliação de impacto, que resumem as etapas do processo de modelagem e apresentar os principais ingredientes que entram na composição de uma plataforma dedicada a simulações de impacto. Também argumentam que o interesse de construir cenários de água e produção de indicadores úteis para a tomada de decisão sobre o uso, distribuição e gestão dos recursos hídricos à escala da bacia.

In mobile ad-hoc networks, congestion occurs with limited resources. The standard TCP congestion control mechanism is not able to handle the special properties of a shared wireless channel. TCP congestion control works very well on the Internet. But mobile ad-hoc networks exhibit some unique properties that greatly affect the design of appropriate protocols and protocol stacks in general, and of congestion control mechanism in particular. As it turned out, the vastly differing environment in a mobile ad-hoc network is highly problematic for standard TCP. Many approaches have been proposed to overcome these difficulties. Mobile agent based congestion control Technique is proposed to avoid congestion in ad-hoc network. When mobile agent travels through the network, it can select a less-loaded neighbor node as its next hop and update the routing table according to the node's congestion status. With the aid of mobile agents, the nodes can get the dynamic network topology in time. In this paper, a mobile agent based congestion control mechanism is presented.

As the number of handicapped people increases worldwide, Intelligent Wheelchairs (IW) are becoming the solution to enable a higher degree of independence for wheelchair users. In addition, IW Projects relevance is increasing, mainly in the fields of robotics and safety-related systems due to their inherent and still unresolved problems related with environment uncertainty, safe communications and collaboration methodologies. This paper describes the development of new communication system, based on multi-agent systems (MAS) and motivated by Intelligent Wheelchair systems. It uses a message-oriented paradigm as a mean for faulttolerant communications in open transmission systems as well as a facilitator for entity collaboration. It provides an overview of the related work in the area, the background and the main constraints to system development, contextualized an IW development project. The results achieved enable us to conclude on the effectiveness and adequacy of the proposed communication model to the field of mobile robots, as well as to conclude that it may outperform JADE in several test scenarios.

As the number of handicapped people increases worldwide, Intelligent Wheelchairs (IW) are becoming the solution to enable a higher degree of independence for wheelchair users. In addition, IW Projects relevance is increasing, mainly in the fields of robotics and safety-related systems due to their inherent and still unresolved problems related with environment uncertainty, safe communications and collaboration methodologies. This paper describes the development of new communication system, based on multi-agent systems (MAS) methodologies and motivated by Intelligent Wheelchair systems, as a mean to enable fault-tolerant communications in open transmission systems and as a agent collaboration enabler. It provides an overview of the related work, the background and the main constraints to system development. It proposes and discusses a new communication model, based on messages, for multi-agent systems, that tackles the problems that exist in a dynamic and uncertain environment in the field of mobile robotics. The achieved results enable us to conclude on the effectiveness of the proposed comunication model and its adequacy to the field of mobile robots in dynamic environments while establishing a comparison with a commonly used MAS, JADE.

We have proposed a life model of our residential sections. This paper proposes the reformulation of town street model based on selforganization of rectangle sections. The model is quit easy to handle the residential sections under asset, since merging two regions into one or splitting one section into two, which are based on rectangle sections, become easy to manipulate them, and also they are amenable to actual transactions in large development areas. We employ new operations to model the residential sections, and the features are partly fit into real town areas. Their operators locally play an interaction with two simple operators merge and join, and globally fitted into residential rectangle sections working as a selforganization. Finally, we compare two: theoretical simulation results and real town statistics in the world.

By integrating processors and wireless communication units into vehicles, it is possible to create a vehicular ad-hoc network (VANET), in which cars share data amongst themselves in order to cooperate and make roads safer and more efficient. A decentralized ad-hoc solution, which does not rely on previously existing infrastructure, Internet connection or server availability, is preferred so the message delivery latency is as short as possible in the case of life-critical situations. However, as it is the case with most new technologies, VANETs will be a prime target for attacks performed by malicious users, who may benefit from affecting traffic conditions. In order to avoid such attacks, one important feature for vehicular networks is trust management, which allows nodes to filter incoming messages according to previously established trust values assigned to other nodes. To generate these trust values, nodes use information acquired from past interactions. Nodes which frequently share false or irrelevant data must have lower trust values than the ones which appear to be reliable. This work proposes TruMan, a trust management model in the context of daily commutes, utilizing the Working Day Movement Model as a basis for node mobility. The results prove to be accurate, detecting nearly all malicious nodes with very few false positives when they constitute up to 50% of the network. The model is also very efficient thanks to the low complexity of the algorithm constituting the trust model.