Cotton cloth is a commonly encountered material in everyday life, and a realistic model for its appearance is needed for rendering clothing and environments in many computer graphics applications. For realism it is important to produce the correct texture when the pattern of threads is resolved in the image, but cloth must also be rendered efficiently in more distant views when the thread patte...

Previous research has shown that Bidirectional Associative Memories (BAM), a special type of artificial neural network, can perform various types of associations that human beings are able to perform with little effort. However, considering a simple association problem, such as associating faces with names, iterative type BAM networks usually take hundreds and sometimes thousands of learning tr...

During mother-infant face-to-face interactions, bidirectional influence could be achieved through either the entraining of periodic cycles in the behavior of each partner or through the stochastic organization of behaviors. To determine whether and how bidirectional influence occurs, we used both timeand frequency-domain techniques to study the interactions of 54 mother-infant pairs, 18 each at...

Many scattering models have been presented in the graphics literature. Few of them, however, have been evaluated through comparisons with real measured data. As the demand for plausible and predictable scattering models increases, more attention is given to performing such comparisons. In this paper we examine the implementation of virtual goniphotometers used to obtain BRDF (bidirectional refl...

Existing bidirectional reflectance distribution function (BRDF) models are capable of capturing the distinctive highlights produced by the fibrous nature of wood. However, capturing parameter textures for even a single specimen remains a laborious process requiring specialized equipment. In this paper we take a procedural approach to generating parameters for the wood BSDF. We characterize the ...

Recent measurement devices for the Bidirectional Texture Function (BTF) offer high parallel capture of the spatial varying reflectance data for material samples. We present an approach to use measurement data from homogenous materials or materials with stochastical mesostructure to obtain data samples for the fitting of BRDF models like CookTorrance. We applied this approach to measured samples...

To some, the relation between bidirectional optimality theory and game theory seems obvious: strong bidirectional optimality corresponds to Nash equilibrium in a strategic game (Dekker and van Rooij 2000). But in the domain of pragmatics this formally sound parallel is conceptually inadequate: the sequence of utterance and its interpretation cannot be modelled reasonably as a strategic game, be...

Bidirectional Associative Memories (BAMs) are artificial neural networks that can learn and recall various types of associations. Although BAMs have shown great promise at modeling human cognitive processes, these models have often been investigated under optimal conditions in which the network is fully connected. Whereas some BAM models have shown to be robust to connection sparseness, those p...

A* is optimal among admissible unidirectional algorithms when searching with a consistent heuristic. Recently, similar optimality bounds have been established for bidirectional search but, no practical algorithm is guaranteed to always achieve this bound. In this paper we study the nature of the number of nodes that must be expanded in any front-to-end bidirectional search. We present an effici...

Bidirectional transformations (bx) are of increasing significance in model-based engineering. Currently bx are defined using a number of specialised transformation languages. In this paper we show how standard UML elements such as use cases and OCL constraints can be used to define bx, thus taking advantage of the wide industrial and educational adoption and support for UML. We define patterns ...