Clustering-based analysis of semantic concept models for video shots

In this paper we present a clustering-based method for representing semantic concepts on multimodal low-level feature spaces and study the evaluation of the goodness of such models with entropy-based methods. As different semantic concepts in video are most accurately represented with different features and modalities, we utilize the relative model-wise confidence values of the feature extraction techniques in weighting them automatically. The method also provides a natural way of measuring the similarity of different concepts in a multimedia lexicon. The experiments of the paper are conducted using the development set of the TRECVID 2005 corpus together with a common annotation for 39 semantic concept

The Vlasov-Poisson system with radiation damping

We set up and analyze a model of radiation damping within the framework of continuum mechanics, inspired by a model of post-Newtonian hydrodynamics due to Blanchet, Damour and Schaefer. In order to simplify the problem as much as possible we replace the gravitational field by the electromagnetic field and the fluid by kinetic theory. We prove that the resulting system has a well-posed Cauchy problem globally in time for general initial data and in all solutions the fields decay to zero at late times. In particular, this means that the model is free from the runaway solutions which frequently occur in descriptions of radiation reaction

An empirical study of inter-concept similarities in multimedia ontologies

Generic concept detection has been a widely studied topic in recent research on multimedia analysis and retrieval, but the issue of how to exploit the structure of a multimedia ontology as well as different inter-concept relations, has not received similar attention. In this paper, we present results from our empirical analysis of different types of similarity among semantic concepts in two multimedia ontologies, LSCOM-Lite and CDVP-206. The results show promise that the proposed methods may be helpful in providing insight into the existing inter-concept relations within an ontology and selecting the most facilitating set of concepts and hierarchical relations. Such an analysis as this can be utilized in various tasks such as building more reliable concept detectors and designing large-scale ontologies

Resin transfer molding for advanced composite primary aircraft structures

Resin Transfer Molding (RTM) has been identified by Douglas Aircraft Company (DAC) and industry to be one of the promising processes being developed today which can break the cost barrier of implementing composite primary structures into a commercial aircraft production environment. The RTM process developments and scale-up plans Douglas Aircrart will be conducting under the NASA ACT contract are discussed

Autonomic Management of Maintenance Scheduling in Chord

This paper experimentally evaluates the effects of applying autonomic management to the scheduling of maintenance operations in a deployed Chord network, for various membership churn and workload patterns. Two versions of an autonomic management policy were compared with a static configuration. The autonomic policies varied with respect to the aggressiveness with which they responded to peer access error rates and to wasted maintenance operations. In most experiments, significant improvements due to autonomic management were observed in the performance of routing operations and the quantity of data transmitted between network members. Of the autonomic policies, the more aggressive version gave slightly better results

Is a friend in need a friend indeed? Inclusion and exclusion in mutual insurance networks in southern Ghana

Mutual insurance has been shown, theoretically and empirically, to be incomplete and limited by asymmetric information and lack of enforcement mechanisms. While some research has shown that networks based on kinship, neighborhood and ethnicity may provide a locus of insurance and thus a way of overcoming these problems, these studies are not fine enough to predict the inclusion and exclusion of individuals. Using data from rural Ghana, we examine the role of social relations in obtaining assistance in the face of shocks. We examine this at both the intra-household and community levels. At the household level, asking for and receiving assistance from the spouse is related to gender, the quality of the marital relationship, and the wealth of household members. At the community level, asking for and receiving help are correlated with membership in a major lineage, participation in secular organizations, the individual¿s fostering history, and anticipated land inheritance. We also show that these factors differ depending on whether the shortfall was for a household or personal item (as perceived by the respondent). This work helps us to identify individuals who are more likely to fall outside of mutual insurance networks and require interventions to help them cope with ris

Measuring concept similarities in multimedia ontologies: analysis and evaluations

The recent development of large-scale multimedia concept ontologies has provided a new momentum for research in the semantic analysis of multimedia repositories. Different methods for generic concept detection have been extensively studied, but the question of how to exploit the structure of a multimedia ontology and existing inter-concept relations has not received similar attention. In this paper, we present a clustering-based method for modeling semantic concepts on low-level feature spaces and study the evaluation of the quality of such models with entropy-based methods. We cover a variety of methods for assessing the similarity of different concepts in a multimedia ontology. We study three ontologies and apply the proposed techniques in experiments involving the visual and semantic similarities, manual annotation of video, and concept detection. The results show that modeling inter-concept relations can provide a promising resource for many different application areas in semantic multimedia processing

Evaluation of a video annotation tool based on the LSCOM ontology

In this paper we present a video annotation tool based on the LSCOM ontology [1] which contains more than 800 semantic concepts. The tool provides four different ways for the user to locate appropriate concepts to use, namely basic search, search by theme, tree traversal and one which uses pre-computed concept similarities to recommend concepts for the annotator to use. A set of user experiments is reported demonstrating the relative effectiveness of the different approaches