Video browsing interfaces and applications: a review

We present a comprehensive review of the state of the art in video browsing and retrieval systems, with special emphasis on interfaces and applications. There has been a significant increase in activity (e.g., storage, retrieval, and sharing) employing video data in the past decade, both for personal and professional use. The ever-growing amount of video content available for human consumption and the inherent characteristics of video data—which, if presented in its raw format, is rather unwieldy and costly—have become driving forces for the development of more effective solutions to present video contents and allow rich user interaction. As a result, there are many contemporary research efforts toward developing better video browsing solutions, which we summarize. We review more than 40 different video browsing and retrieval interfaces and classify them into three groups: applications that use video-player-like interaction, video retrieval applications, and browsing solutions based on video surrogates. For each category, we present a summary of existing work, highlight the technical aspects of each solution, and compare them against each other

Incorporating seascape ecology into the design and assessment of marine protected areas

Seascape ecology is an emerging sub-discipline of marine ecology, which examines the effect of spatial heterogeneity in marine ecosystems on ecological processes and species distributions. The opportunity to study seascape ecology in many coastal regions has been greatly assisted by advances in remote sensing technologies, which can acquire detailed habitat data over a range of spatial scales. This now allows quantification of spatial patterns in seascapes and the scientific examination of the ecological consequences of such patterns. Current research applying this approach has begun to demonstrate the importance of seascape connectivity and structural complexity in driving spatial variability of marine fish assemblages. Much of this research however, has focussed on tropical regions and as a result the effect of seascape patterning on temperate fishes remains poorly resolved. The aim of this thesis was to examine the seascape ecology of temperate fishes in two Marine Protected Areas (MPAs) in south-east Australian waters and also examine how this approach can aid in the design and assessment of MPAs. I achieved this by investigating spatial variability in temperate fish assemblages over three scales to examine the effect of i) three-dimensional reef structural complexity, ii) differences among habitat types (seagrass, rocky reef and unvegetated sediment) and iii) the seascape connectivity of habitats. I used baited remote underwater video systems (BRUVs) to survey demersal and mid-water fish assemblages in conjunction with existing habitat mapping to examine the relationship between fish and their habitats. In the Lord Howe Island Marine Park (LHIMP), reef structural complexity strongly influenced the abundance of yellowtail kingfish; Seriola lalandi. Despite being heavily targeted by fishers, a ‘conventional’ (GLM) assessment on the LHIMP revealed no difference in the abundance of S. lalandi between fished and unfished zones. However, on accounting for reef structural complexity in the assessment, I revealed substantially higher abundances of S. lalandi in unfished zones. This positive effect was only observed in their optimal habitat, reefs of high structural complexity. In the Jervis Bay Marine Park (JBMP), habitat type (seagrass, rocky reef and unvegetated sediment) was a strong and consistent predictor of the demersal fish assemblage but did not influence fishes in the mid-water environment. Although habitat influenced the abundance of many demersal fishes, some taxa from the demersal assemblage displayed no affinity to underlying habitat type. Seascape composition and connectivity also appeared to strongly influence temperate fish assemblages. The abundance and diversity of temperate fishes was correlated with the area of rocky reef and seagrass within the surrounding seascape. The apparent importance of seascape connectivity was also noted in the LHIMP, where adult black rockcod (Epinephelus daemelii) were only recorded in areas adjacent to their nursery grounds. Finally, I sought to compare the effectiveness of attractants other than bait (sight and sound stimuli) to entice pelagic fishes to video systems positioned in the mid-water environment. I found the combination of sight, sound and scent attractants on mid-water remote underwater videos (RUVs) recorded a substantially higher abundance and shorter time of first arrival of pelagic fishes compared to RUVs with one or no attractant. I suggest future studies using this sampling method to survey pelagic fishes employ multiple attractants. My findings demonstrate that temperate fishes are influenced by patterns in seascapes and habitats at a number of spatial scales. They also have important implications for spatial conservation strategies such as MPAs, particularly in terms of their design, assessment and adaptive management. Representation of seascape variability over a number of spatial scales in MPA planning is likely to better represent temperate fish assemblages. Furthermore, I demonstrate that habitat classes and measures of structural complexity are appropriate surrogates for certain fishes, which is useful in MPA planning. Finally, I demonstrate that accounting for seascape variability in MPA evaluation is likely to provide a better assessment and clearer understanding of ecological change associated with this management action. In conclusion, integrating seascape ecology into MPA science will increase the usefulness of this conservation strategy to combat growing declines in global marine biodiversity

Evaluating the Efficacy of Using Geomorphology as a Surrogate to Benthic Habitat on the Miami Terrace

The deep-sea is a vast and relatively sparsely characterized domain. As little as 0.01% of deep-sea benthic habitats have been characterized in detail. Characterizing the distribution of organisms and environmental components of the deep-sea is pivotal to the creation and implementation of successful resource management. Benthic habitat maps are a good method to inventory and characterize deep-sea habitats. Recent advances in technology, such as multibeam sonar and remotely operated vehicles (ROVs), have allowed for greater understanding of these ecosystems. As it is difficult and expensive to collect data deep-sea benthic community composition, environmental surrogates of biological data would be economically beneficial. Ideally, a surrogate is an easily-measured abiotic indicator that greatly influences benthic community composition. The quality of a surrogate can be extrapolated to represent the quality of benthic habitat. The Miami Terrace is a deep-sea ecosystem that has begun to be explored and characterized. Previous studies noted that community compositions vary with broad-scale geomorphology on the Miami Terrace. This study addresses a swath of data collected from the Miami Terrace to determine if geomorphology in high resolution bathymetry could serve as a viable surrogate to biological data for the initial characterization of benthic habitats on the Miami Terrace. Data from cable impact assessment surveys for the South Florida Ocean Measurement Facility (SFOMF) and the Department of Energy were utilized in this study. Images from these surveys were analyzed to generate and detail twelve transects across a section of the Miami Terrace. This cross section of the terrace had previously been sectioned into distinct geomorphologic zones (Messing et al., 2012). The geomorphologic zones assessed in this study were High Slope Inner Terrace (HSIT), Low Slope Inner Terrace (LSIT), High Slope Outer Terrace Platform (HSOTP), Low Slope Outer Terrace Platform (LSOTP), High Slope Outer Terrace Ridge (HSOTR), and Low Slope Outer Terrace Ridge (LSOTR). Images from these transects were analyzed to generate percent cover and community data. This data includes overall organism density, species richness, and an inventory of all organisms greater than 4 cm identified to the lowest taxonomic level possible. This data was taken in concert with previously collected environmental data (e.g. depth, slope, and geomorphology) and subjected to multivariate statistical analysis. Patterns in organism density across the transects align with the progression of the transects by slope and geomorphologic region. Depth was seen to increase from Inner Terrace to Outer Terrace Platform. The Outer Terrace Ridge exhibited an increase in the percent cover of hardbottom habitat; which is preferential for many organisms. This corresponded to a shift in the organism density of multiple Cnidarians and Poriferans. In particular, the density of stylasterids and several sponges increased towards the Outer Terrace Ridge. One High Slope Inner Terrace transect juts into the Outer Terrace Platform, and it was more similar to Outer Terrace Platform transects than those of the Inner Terrace. This suggests that area of Inner Terrace jutting into the Outer Terrace Platform may need to be reassigned as Outer Terrace Platform. Analysis of variance by region and slope yielded that the density of multiple species varies with geomorphology across the study area, and high slope areas had significantly higher species richness than areas of low slope. These results support that geomorphology could serve as a surrogate for the Miami Terrace; however, it is likely a combination of geomorphology and another environmental factor (e.g., percent cover substrate or depth) would better serve to predict distribution of species on the Miami Terrace. The results of this study support that geomorphologic region, slope, depth, and percent cover of substrate can be used to determine different deep-sea habitats on the Miami Terrace. The influence of geomorphology on organism densities was varied, and thus its predictive capacity and efficacy as a surrogate remains limited. Nevertheless, the necessity for ecological baselines to guide management decisions is greater than the uncertainty associated with the use of geomorphology as a surrogate on the Miami Terrace

AN EXAMINATION OF THE INFLUENCE OF DISTILLATION ON THE COMBUSTION BEHAVIOR OF APPARENTLY EQUIVALENT SURROGATE FUELS

Use of surrogates to emulate the combustion behaviors of prevaporized real fuels has been widely demonstrated in the literature. However, many combustion applications utilize atomized fuel sprays, and for these configurations, the assumption of fuel property homogeneity in prevaporized fuel combustion is tenuous. This work uses a simplified distilling droplet model to demonstrate a real potential for vaporization-coupled deviations from the single-valued combustion property targets used to characterize prevaporized combustion behaviors. To verify the model-based observations, flame blowout measurements from a custom-built annular spray burner rig are measured. Sets of essentially equivalent prevaporized jet fuel and gasoline surrogates suggested in the literature, and four nC9 surrogates composed of varying proportions of chemically similar n-alkanes are tested to examine blowout threshold variations driven by distillation behavior. The differing volatility characteristics of these surrogates emphasizes the influence of volatility on certain combustion behaviors (e.g., blowout) in a spray combustion environment. Noted variations in blowout limits (and also allowing for other limiting combustion behaviors not studied here) highlights the need to consider the coupling between distillation and combustion behavior

Indexing, browsing and searching of digital video

Video is a communications medium that normally brings together moving pictures with a synchronised audio track into a discrete piece or pieces of information. The size of a “piece ” of video can variously be referred to as a frame, a shot, a scene, a clip, a programme or an episode, and these are distinguished by their lengths and by their composition. We shall return to the definition of each of these in section 4 this chapter. In modern society, video is ver

Complexity Science in Human Change

This reprint encompasses fourteen contributions that offer avenues towards a better understanding of complex systems in human behavior. The phenomena studied here are generally pattern formation processes that originate in social interaction and psychotherapy. Several accounts are also given of the coordination in body movements and in physiological, neuronal and linguistic processes. A common denominator of such pattern formation is that complexity and entropy of the respective systems become reduced spontaneously, which is the hallmark of self-organization. The various methodological approaches of how to model such processes are presented in some detail. Results from the various methods are systematically compared and discussed. Among these approaches are algorithms for the quantification of synchrony by cross-correlational statistics, surrogate control procedures, recurrence mapping and network models.This volume offers an informative and sophisticated resource for scholars of human change, and as well for students at advanced levels, from graduate to post-doctoral. The reprint is multidisciplinary in nature, binding together the fields of medicine, psychology, physics, and neuroscience

Statistical and Graph-Based Signal Processing: Fundamental Results and Application to Cardiac Electrophysiology

The goal of cardiac electrophysiology is to obtain information about the mechanism, function, and performance of the electrical activities of the heart, the identification of deviation from normal pattern and the design of treatments. Offering a better insight into cardiac arrhythmias comprehension and management, signal processing can help the physician to enhance the treatment strategies, in particular in case of atrial fibrillation (AF), a very common atrial arrhythmia which is associated to significant morbidities, such as increased risk of mortality, heart failure, and thromboembolic events. Catheter ablation of AF is a therapeutic technique which uses radiofrequency energy to destroy atrial tissue involved in the arrhythmia sustenance, typically aiming at the electrical disconnection of the of the pulmonary veins triggers. However, recurrence rate is still very high, showing that the very complex and heterogeneous nature of AF still represents a challenging problem. Leveraging the tools of non-stationary and statistical signal processing, the first part of our work has a twofold focus: firstly, we compare the performance of two different ablation technologies, based on contact force sensing or remote magnetic controlled, using signal-based criteria as surrogates for lesion assessment. Furthermore, we investigate the role of ablation parameters in lesion formation using the late-gadolinium enhanced magnetic resonance imaging. Secondly, we hypothesized that in human atria the frequency content of the bipolar signal is directly related to the local conduction velocity (CV), a key parameter characterizing the substrate abnormality and influencing atrial arrhythmias. Comparing the degree of spectral compression among signals recorded at different points of the endocardial surface in response to decreasing pacing rate, our experimental data demonstrate a significant correlation between CV and the corresponding spectral centroids. However, complex spatio-temporal propagation pattern characterizing AF spurred the need for new signals acquisition and processing methods. Multi-electrode catheters allow whole-chamber panoramic mapping of electrical activity but produce an amount of data which need to be preprocessed and analyzed to provide clinically relevant support to the physician. Graph signal processing has shown its potential on a variety of applications involving high-dimensional data on irregular domains and complex network. Nevertheless, though state-of-the-art graph-based methods have been successful for many tasks, so far they predominantly ignore the time-dimension of data. To address this shortcoming, in the second part of this dissertation, we put forth a Time-Vertex Signal Processing Framework, as a particular case of the multi-dimensional graph signal processing. Linking together the time-domain signal processing techniques with the tools of GSP, the Time-Vertex Signal Processing facilitates the analysis of graph structured data which also evolve in time. We motivate our framework leveraging the notion of partial differential equations on graphs. We introduce joint operators, such as time-vertex localization and we present a novel approach to significantly improve the accuracy of fast joint filtering. We also illustrate how to build time-vertex dictionaries, providing conditions for efficient invertibility and examples of constructions. The experimental results on a variety of datasets suggest that the proposed tools can bring significant benefits in various signal processing and learning tasks involving time-series on graphs. We close the gap between the two parts illustrating the application of graph and time-vertex signal processing to the challenging case of multi-channels intracardiac signals