13425018
Lithofacies recognition hybrid bench
Well offshore petroleum exploration is a risky, but very profitable task. Determining the rock formation of each layer of a given reservoir diminishes the risks of expending a great deal of money drilling dry wells. Since collecting offshore rock samples is difficult and expensive, geologists must decide upon drilling based on indirect measures called well log. Traditional statistical methods have been used to assist this task. Neural networks have also been successfully used. As an alternative fuzzy logic based systems have an extra appeal of intuitive comprehension of some uncertainties. This paper presents a hybrid tool that combines neural networks, fuzzy logic and neuro-fuzzy logic to improve human intuition when analyzing the potential of oil fields.
29246421
Sharing design perspectives through storytelling
Design consists of analyzing scenarios and proposing artifacts, obeying the initial set of requirements that lead from initial to goal state. Finding or creating alternative solutions, analyzing them, and selecting the best one are expected steps in the designer’s decision making process. Very often, not a sole designer, but a team of them is engaged in the design process, sharing their expertise and responsibility to achieve optimum projects. In a design team, most conflicts occur due to misunderstanding of one’s assessment of specifications and contexts. Decision explanations play a key role in teamwork success. Designers are rational agents trained to follow rational methods. Acceptable justifications include value function, requirements, constraints, and criteria. Generally, explanations are delivered in a multimedia fashion, composed of text, graphics and gestures, to provide the audience the ability to perceive what was contextually imagined. The more spatial the reasoning is, the richer the explanation channel should be. This paper presents CineADD, a design explanation generation model based on cinema techniques such as animation, scripting, editing, and camera movements. The idea is to provide designers with a tool for describing the way their projects should be visually explained, as in a movie. Designers develop their projects in an active design document environment. Rationale is captured as a design model, so explanations can be generated instead of retrieved. The captured design model serves as a base to visually reconstruct design, giving emphasis and guidance by using movie storytelling techniques. CineADD was implemented for the domain of oil pipeline layout showing the feasibility of this approach. We expect CineADD to become a commodity attachable to any intelligent CAD system.
1671148
Aspects in Agent-Oriented Software Engineering: Lessons Learned
Several concerns in the development of multi-agent systems (MASs) cannot be represented in a modular fashion. In general, they inherently affect several system modules and cannot be explicitly captured based on existing software engineering abstractions. These crosscutting concerns encompass internal agent properties and systemic properties, such as learning, code mobility, error handling, and context-awareness. In this context, it is important to systematically verify whether emerging development paradigms support improved modularization of the crosscutting concerns relative to MASs. This paper reports some lessons learned based on our experience in using aspect-oriented techniques and methods to address these problems. In the light of these lessons, related work and a set of future research directions are also discussed.
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.
31153205
Separation of Concerns in Multi-agent Systems: An Empirical Study
With multi-agent systems (MASs) growing in size and complexity, the separation of their concerns throughout the different development phases is crucial to MAS engineers. Separation of concerns is a well-known principle in software engineering to achieve improved reusability and maintainability of complex software. Hence it is necessary to investigate systematically whether ions from object-oriented (OO) software engineering are able to isolate explicitly MAS concerns. This paper presents an empirical study that evaluates the degree to which abstractions associated with two OO techniques enable modularization of MAS concerns. The selected techniques involve basic OO ions, such as classes and objects, and more sophisticated ones, namely design patterns and aspects. The gathered results shown that the use of aspects allowed the construction of a MAS with a significant improvement in the modularization of different concerns. Also, the use of aspects resulted in: (i) fewer lines of code, (ii) fewer design and implementation components, and (iii) lower coupling between the components. However, the aspect-oriented approach produced lower cohesion in the MAS components. Finally, an important finding of this empirical study is that aspects supported a better alignment with higher-level abstractions from agent-oriented design models.
45365979
Software Engineering for Multi-Agent Systems