35,047 research outputs found
A knowledge based software engineering environment testbed
The Carnegie Group Incorporated and Boeing Computer Services Company are developing a testbed which will provide a framework for integrating conventional software engineering tools with Artifical Intelligence (AI) tools to promote automation and productivity. The emphasis is on the transfer of AI technology to the software development process. Experiments relate to AI issues such as scaling up, inference, and knowledge representation. In its first year, the project has created a model of software development by representing software activities; developed a module representation formalism to specify the behavior and structure of software objects; integrated the model with the formalism to identify shared representation and inheritance mechanisms; demonstrated object programming by writing procedures and applying them to software objects; used data-directed and goal-directed reasoning to, respectively, infer the cause of bugs and evaluate the appropriateness of a configuration; and demonstrated knowledge-based graphics. Future plans include introduction of knowledge-based systems for rapid prototyping or rescheduling; natural language interfaces; blackboard architecture; and distributed processin
Global (in Time) Solutions to the 3D-Navier-Stokes Equations on R^3
A well-known unsolved problem (in the classical theory of fluid mechanics) is
to identify a set of initial velocities, which may depend on the viscosity, the
body forces and possibly the boundary of the fluid that will allow global in
time solutions to the three-dimensional Navier-Stokes equations. (These
equations describe the time evolution of the fluid velocity and pressure of an
incompressible viscous homogeneous Newtonian fluid in terms of a given initial
velocity and given external body forces.) A related problem is to provide
conditions under which we can be assured that the numerical approximation of
these equations, used in a variety of fields from weather prediction to
submarine design, have only one solution. In earlier papers, we solved this
problem for a bounded domain. In this paper, we use an approach based on
additional physical insight, that allows us to prove that there exists unique
global in time solutions to the Navier-Stokes equations on R^3
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