5283455
Customizing Aspect-Oriented Variabilities using Generative Techniques
With the emergence of aspect-oriented (AO) techniques, crosscutting concerns can be now explicitly modularized and exposed as additional variabilities in program families. Hence, the development of highly customizable software family architectures requires the explicit handling of crosscutting variabilities through domain engineering and application engineering steps. In this context, this paper presents a generative model that addresses the implementation and instantiation of variabilities encountered in AO software family architectures. The use of our model allows for an early specification and preparation of AO variabilities, which in turn can be explicitly customized by means of domain engineering activities. All the variabilities of the architecture are modeled using feature models. In application engineering, developers can request an instance of the AO architecture in a process of two stages: (i) the definition of a feature model instance which specifies the resolution of variabilities for the AO family architecture; and (ii) the definition of a set of crosscutting relationships between features.
39578766
On the Quantitative Assessment of Modular Multi-Agent Architectures
10325620
Agents in object-oriented software engineering
18526386
A Systematic Approach for Including Machine Learning in Multi-agent Systems
Large scale multi-agent systems (MASs) in unpredictable environments must use machine learning techniques to perform their goals and improve the performance of the system. This paper presents a systematic approach to introduce machine learning in the design and implementation phases of a software agent. We also present an incremental implementation process for building asynchronous and distributed agents, which suppors the combination of machine learning strategies. This process supports the stepwise building of adaptable MASs for unknown situations, improving their capacity to scale up. We use the Trading Agent Competition (TAC) environment as a case study to illustrate the suitability of our approach.
15338420
Aspectizing Multi-agent Systems: From Architecture to Implementation
Agent architectures have to cope with a number of internal properties (concerns), such as autonomy, learning, and mobility. As the agent complexity increases, these agent properties crosscut each other and the agent’s basic functionality. In addition, multi-agent systems encompass multiple agent types with heterogeneous architectures. Each of these agent types has different properties, which need to be composed in different ways. In this context, the separation and the flexible composition of agent concerns are crucial for the construction of heterogeneous agent architectures. Moreover the separation of agent concerns needs to be guaranteed throughout the different development phases, especially from the architectural to the implementation phase. Existing approaches do not provide appropriate support for the modularization of agent properties at the architectural stage, and do not promote a smooth transition to the system implementation. This paper presents an aspect-oriented method that allows for a better separation of concerns, supporting the systematic aspectization of agent properties through the architectural definition, detailed design and implementation. A multi-agent system for paper reviewing management is assumed as a case study through this paper to show the applicability of our proposal.
979214
Enhancing agent-oriented models with aspects
The modular representation of concerns is imperative in the design modeling of multi-agent systems (MASs). However, MAS designers typically face a number of concerns that inherently affect several system agents and their respective internal elements, such as actions and goals. These crosscutting concerns encompass both internal and systemic properties, such as learning, mobility, error handling, and security. Without an explicit modeling of such MAS properties, designers can not properly communicate and reason about them and their broadly-scoped effects. The result is a multitude of agent-oriented design breakdowns: poor traceability from requirements to design models, hindering of reuse opportunities, and decreased evolvability. This paper presents an enhancement of an existing agent-oriented modeling language with aspects. We illustrate the use of our approach through some classical examples of crosscutting concerns in agent-oriented design models.
17377991
Applying the HYRIWYG incentive mechanism in a recommender system
The use of recommender systems (RS) has become common in several e-commerce Web sites. Collaborative filtering is one of the most popular RS techniques. It infers a user's predilections based on similarity with other users. However, to work correctly, the RS depends on the evaluator's participation with truly opinions. The HYRIWYG mechanism proposes an incentive model to motivate users to contribute with a high number of opinions and, more important, guaranteeing the truthfulness of the information. In this paper, we present HYRIWYG mechanism and discuss it using an empirical study in the movie evaluation domain. Initial results highlight the great potential benefits of using this kind of incentive mechanism.
15357706
Modeling flow around a microrotor in creeping flow using a quasi-steady-state analysis
Paramagnetic microsphere suspensions placed in a rotating magnetic field aggregate to form rotating magnetic chains. These chains that are several tens of micrometers in length act as microrotors, and can be modeled as circular cylinders. The flow and associated micromixing around these cylinders rotating about their radial axis is studied for a very low Reynolds number, creeping-flow system.. Time-scales for momentum transfer are much smaller than boundary movement, hence a quasi-steady approximation can be used. The flow is derived at every instant from the case of a steady motion of a horizontally translating cylinder, with the rotation approximated to a series of incremental translations. A numerical simulation was used to determine the pathlines and material lines of point fluid elements, which were analyzed to understand the behavior of the microfluidic system. The results indicate the flow to be unsteady, with chaotic advection observed in the system. The flow is primarily two-dimensional with planar fluid movement limited to the immediate area around the rotating cylinder, with a small disturbance in the axial direction that is experienced up to many diameters away. Elliptic and star shaped pathlines, including periodic orbits, are observed depending on the fluid element's initial location. The trajectories and phase angles compare well with the limited experimental results, as well as with data from particle dynamics simulations. Material lines and streaklines display stretching and folding, which are indicative of the chaotic behavior of the system. The material lines have similar lengths for the same amount of rotation at different speeds, and the affect of rotational speeds appears to be primarily to change the time of mixing.
5520687
Web Navigation Patterns
44575256
An X-Ray of the Brazilian e-Gov Web Sites
The digital inclusion promotes the reduction of social inequalities. Based on this principle, the Brazilian Government has been setting up an increasing number of Web access locations to render virtual support to its citizens. However, there are no guidelines for the construction and assessment of these electronic Government (e-Gov) sites. In this article we measure the web site quality in the e-Gov domain with the following proprieties: usability, accessibility, interoperability, security, privacy, information reliability, and service agility. We implemented our method, by using a checklist tool, in the evaluation of 127 Brazilian government sites (federal, state and municipal). Our method proved itself efficient in the diagnosis and identification of specific problems in the e-Gov site domain.