How the brain processes pattern mixtures is not well understood. The prevailing views are 1) that difficult tasks are processed in serial, and easy tasks in parallel 2) in fast image presentations with effective masking leaves little time for re-entrant neural dynamics other than feed-forward, excluding the possibility of top-down processing. We hypothesize that to process pattern mixtures, the...

We present a top-down lower bound method for depth 3 AND-OR-NOT circuits which is simpler than the previous methods and in some cases gives better lower bounds. In particular we prove that depth 3 AND-OR-NOT circuits that compute PARITY resp. MAJORITY require size a t least 20.6 18.. fi resp. 2°.849...fi. This is the first simple proof of a strong lower bound by a top-down argument for non-mono...

We provide string theory examples where a toy model of a SUSY GUT or the MSSM is embedded in a compactification along with a gauge sector which dynamically breaks supersymmetry. We argue that by changing microscopic details of the model (such as precise choices of flux), one can arrange for the dominant mediation mechanism transmitting SUSY breaking to the Standard Model to be either gravity me...

A joint effort by the University of California at Berkeley and Delft University of Technology to develop a graduate engineering ethics course for PhD students encountered two types of challenges: academic and institutional. Academically, long-term collaborative research efforts between engineering and philosophy faculty members might be needed before successful engineering ethics courses can be...

The focus of this paper is on pointing gestures that do not function as deictic pointing to a concrete referent but rather as structuring the flow of information. Examples are given on their use in giving feedback and creating a common ground in natural conversations, and their meaning is described with the help of semantic themes of the Index Finger Extended gesture family. A communication mod...

We briefly review attempts to construct string theories that yield the standard model, concentrating on models with a geometric interpretation. Calabi-Yau compactifications are discussed in the context of both the weakly coupled heterotic string and the strongly coupled version, heterotic M-theory. Similarly, we consider orbifold compactifications of weakly coupled heterotic theory and of Type ...

This paper studies budget processes, both theoretically and experimentally. We compare the outcomes of bottom-up and top-down budget processes. It is often presumed that a top-down budget process leads to a smaller overall budget than a bottom-up budget process. Ferejohn and Krehbiel (1987) showed theoretically that this need not be the case. We test experimentally the theoretical predictions o...

Most process research relies heavily on the use of terms and concepts whose validity depends on a variety of assumptions to be met. As it is difficult to guarantee that they are met, such work continually runs the risk of being invalid. We propose a different and complementary approach to understanding process: Perform all description bottom-up and based on hard data alone. We call the approach...

In South Africa, up to 70% of children of school-going age with disabilities are out of school. Of those who do attend, most are still in separate, “special” schools for learners with disabilities. This situation prevails despite the push for the educational inclusion of learners with disabilities over twelve years ago by the South African policy document, the Education White Paper 6. In this a...

A common trend for manufacturing systems is an increasing flexibility. More and more bottom-up aspects are coming into the engineering processes.