Mathematics is an enigmatic subject in which a few succeed with disarming ease, whilst others seem doomed to failure. After analysing the responses of many children performing simple tasks in arithmetic, we find a phenomenon occurring which suggests a reason for this catastrophic divergence in performance. Quite simply we find that

hill climbing Abstract. Conceptual clustering is an important way of summarizing and explaining data. However, the recent formulation of this paradigm has allowed little exploration of conceptual clustering as a means of improving performance. Furthermore, previous work in conceptual clustering has

current FFTW3 version flexible and adaptive. We further discuss a new algorithm for real-data DFTs of prime size, a new way of implementing DFTs by means of machine-specific single-instruction, multiple-data (SIMD) instructions, and how a special-purpose compiler can derive optimized implementations

The Ponder language provides a common means of specifying security policies that map onto various access control implementation mechanisms for firewalls, operating systems, databases and Java. It supports obligation policies that are event triggered conditionaction rules for policy based management

signal representations. Given a set of training signals, we seek the dictionary that leads to the best representation for each member in this set, under strict sparsity constraints. We present a new method—the K-SVD algorithm—generalizing the u-means clustering process. K-SVD is an iterative method

Probabilistic inference is an attractive approach to uncertain reasoning and empirical learning in artificial intelligence. Computational difficulties arise, however, because probabilistic models with the necessary realism and flexibility lead to complex distributions over high-dimensional spaces

others have resisted changes to this day. Yet a detailed analysis of the meanings of globalization, along with its challenges and opportunities for engineering education, remains to be done. In this paper I survey theories of globalization, analyze its connection with demands for flexibility in education

for facing risk is a multiple of the variance of the risk. This means that risk compensation cannot vary independently of interest rate volatility. I also describe and empirically estimate a class of models that is broader than the standard a#ne class. These "essentially a#ne" models retain

We discuss findings from an ethnographic study of instant messaging (IM) in the workplace and its implications for media theory. We describe how instant messaging supports a variety of informal communication tasks. We document the affordances of IM that support flexible, expressive communication

This study provides a motivation for exposing young pupils to a wider variety of division problems than is currently the case. Year 5 and 6 English pupils ' strategies for solving six written symbolic division problems were classified and analysed in terms of success. A flexible choice of a