the dynamic nature of projects and the fact that they are carried out in changing environments, justify the need for their periodic monitoring and control. collection of information about the performance of projects at control points costs money. the corrective actions that may need to be taken to bring the project in line with the plan also costs money. on the other hand, penalties are usually...

Scaled experimentation is an important experimental approach but known to be limited by scale effects, which have the undesirable effect of changing behaviour a system with scale. Such behavioural changes can on occasions so marked as make scaled experiment almost worthless. Until very recently, there has been no universal solution this problem most experiments founded dimensional analysis and ...

I consider two usages of the expression “gauge theory”. On one, a gauge theory is a theory with excess structure; on the other, a gauge theory is any theory appropriately related to classical electromagnetism. I make precise one sense in which one formulation of electromagnetism, the paradigmatic gauge theory on both usages, may be understood to have excess structure, and then argue that gauge ...

Electromagnetism is usually understood as a theory describing how charged particles and eletromagnetic elds interact. In this paper I argue that a double ontology comprising both particles and elds is problematic. Either we should think of electromagnetism as a theory about charged particles directly interacting with each other, or as theory of elds whose local interactions are manifested as...

Minsky subscribes to neither of these extremist views. Instead, he argues that Artificial Intelligence must employ many approaches. Artificial Intelligence is not like circuit theory and electromagnetism. There is nothing wonderfully unifying like Kirchhoff's laws are to circuit theory or Maxwell's equations are to electromagnetism. Instead of looking for a "Right Way", Minsky believes that the...

Maxwell equations are the basis of the theory of electromagnetic fields. In the stationary case they split into independent problems for electric and magnetic fields. For the electric field in conductive media electrical conductivity problem is formulated, and in insulators the problem of electrostatics is formulated. Equations for stationary problems are of elliptic type, whereas in general th...