A Bayesian generalized expectation - maximization (GEM) algorithm using a locally correlated Markov random field prior in the form of a Gibbs function is developed for emission tomography. A closeform coordinate gradi...
详细信息
The paper describes a 3-dimensional Shape Descriptor Function (SDF) which is invariant under the action of SO(3). We concentrate here on the analytical derivation of the SSD, and show how certain requirements constrai...
详细信息
Using the framework of the parallel logical language. Concurrent Prolog, the concepts and the strategies for the parallel logic simulation are defined. Some types of a prototypical parallel logic simulator are impleme...
详细信息
In this paper, we consider application of 2-D stochastic models discussed in [1] to develop noncausal FIR filters for restoration of images degraded by additive white noise. The semicausal model of [1] is used to desi...
详细信息
Digital filtering techniques for speckle reduction are studied using several conventional filters and homomorphic filters. It is shown that homomorphic filtering has higher resolution than straightforward linear filte...
详细信息
Finding knowledge – or meaning – in data is the goal of every knowledge d- covery e?ort. Subsequent goals and questions regarding this knowledge di?er amongknowledgediscovery(KD) projectsandapproaches. Onecentralque...
详细信息
ISBN:
(数字)9783540476986
ISBN:
(纸本)9783540476979
Finding knowledge – or meaning – in data is the goal of every knowledge d- covery e?ort. Subsequent goals and questions regarding this knowledge di?er amongknowledgediscovery(KD) projectsandapproaches. Onecentralquestion is whether and to what extent the meaning extracted from the data is expressed in a formal way that allows not only humans but also machines to understand and re-use it, i. e. , whether the semantics are formal semantics. Conversely, the input to KD processes di?ers between KD projects and approaches. One central questioniswhetherthebackgroundknowledge,businessunderstanding,etc. that the analyst employs to improve the results of KD is a set of natural-language statements, a theory in a formal language, or somewhere in between. Also, the data that are being mined can be more or less structured and/or accompanied by formal semantics. These questions must be asked in every KD e?ort. Nowhere may they be more pertinent, however, than in KD from Web data (“Web mining”). Thisis due especially to the vast amounts and heterogeneity of data and ba- ground knowledge available for Web mining (content, link structure, and - age), and to the re-use of background knowledge and KD results over the Web as a global knowledge repository and activity space. In addition, the (Sem- tic) Web can serve as a publishing space for the results of knowledge discovery from other resources, especially if the whole process is underpinned by common ontologies.
暂无评论