Novelty detection in video surveillance using hierarchical neural networks

Abstract. A hierarchical self-organising neural network is described for the detection of unusual pedestrian behaviour in video-based surveillance systems. The system is trained on a normal data set, with no prior information about the scene under surveillance, thereby requiring minimal user input. Nodes use a trace activation rule and feedforward connections, modified so that higher layer nodes are sensitive to trajectory segments traced across the previous layer. Top layer nodes have binary lateral connections and corresponding “novelty accumulator” nodes. Lateral connections are set between co-occurring nodes, generating a signal to prevent accumulation of the novelty measure along normal sequences. In abnormal sequences the novelty accumulator nodes are allowed to increase their activity, generating an alarm state

Exploring the sail training voyage as a cultural community

Ed. D ThesisStudies have demonstrated that participation on a sail training voyage, as a structured educational activity that is more than mere adventure (McCulloch et al., 2010: 661), enhances self-constructs, and inter- and intra-personal skills. Many studies have followed an outcome-based approach to measure various self-constructs at pre-, on- and/or post-voyage intervals, however, there has been limited investigation as to how these outcomes may be generated; or how they may be ‘laminated’ in participants’ personal and social development, and thereby influence skills for life and work, such as social and emotional skills and supporting educational attainment (Feinstein, 2015). The origins of modern day sail training voyages are to be found in the traditions and practices of the age of sail, representing a rich socio-cultural and historical setting for participants to explore the voyage experience. This study takes an ethnographic approach to explore a six-day sail training voyage as a ‘cultural community’, and how this concept may generate beneficial outcomes through apprenticeship and guided participation (after Rogoff, 1990; Rogoff and Angelillo, 2002). Few studies on this topic have extended their scope of interest beyond the young crew participants; this study engages with all of those who sailed on the voyage, comprising twelve 12- and 13-year old girls, two teachers, and the full-time and volunteer sea-staff (and the researcher as a participant observer). This voyage-based case study uses a range of methods, including visual methods, as pre-, on- and post-voyage research activities, complemented with a post-voyage photo elicitation activity and semi-structured interviews to construct a rich, detailed account of the study voyage

Steering a course towards eudaimonia: the effects of sail training on well-being and character

Sail training voyages have been shown to enhance self-constructs and inter-personal and intra-personal skills. It is suggested through this case study approach with twelve 14 year-old crew participants that such an experience contributes towards well-being and character development in emerging adulthood. An audit of voyage-based experiences generated an inventory of 58 authentic activities and participants completed questionnaires immediately post-voyage (T1) and six months later (T2) to rate the significance of each activity. The highest rated activities reflected Maslow’s lower order of needs with a two thirds correspondence at T1 and T2. Helming (or steering the vessel) was ranked as the most significant activity by participants in both time periods, although participants had questioned their ability to do this before the voyage. Helming is suggested to activate cognitive, psychomotor and affective domains in an authentic adventure education experience that contributes to hedonic well-being and may provide a course towards eudaimonia

Prosody and intrasyllabic timing in French

Durational variation associated with accentuation and final lengthening is examined in a corpus of articulatory data for French. Both factors are associated with measurable differences in acoustic duration. However two different articulatory strategies are employed to make these contrasts although both result in superficially longer and more displaced gestures.Parts of this research were supported by the National Science Foundation (USA) under Grant no. IRI-8858109 to Mary Beckman, the Ohio State University, and by the National Institutes of Health (USA) under Grant no. NS-13617 to Haskins Laboratories

Guantanamo and Its Aftermath: U.S. Detention and Interrogation Practices and Their Impact on Detainees

Based on interviews with former detainees held in Afghanistan and Guantanamo Bay, attorneys, officials, and military personnel, details interrogation practices, conditions of incarceration, and their long-term effects. Urges a nonpartisan investigation

ASTO (Association of Sail Training Organisations) Theory of Change

This session will include a brief presentation on the ASTO Theory of Change – a description of how we think change happens for our participants through sail training experiences. It will look at the personal development, skills and social development activities mentioned in the Theory of Change and using an interactive approach, will encourage delegates to think about and discuss their own practice (on borad), and how this might influence the learning that takes place and manifests itself

Harvest-induced disruptive selection increases variance in fitness-related traits

The form of Darwinian selection has important ecological and management implications. Negative effects of harvesting are often ascribed to size truncation (i.e. strictly directional selection against large individuals) and resultant decrease in trait variability, which depresses capacity to buffer environmental change, hinders evolutionary rebound and ultimately impairs population recovery. However, the exact form of harvest-induced selection is generally unknown and the effects of harvest on trait variability remain unexplored. Here we use unique data from the Windermere (UK) long-term ecological experiment to show in a top predator (pike, Esox lucius) that the fishery does not induce size truncation but disruptive (diversifying) selection, and does not decrease but rather increases variability in pike somatic growth rate and size at age. This result is supported by complementary modelling approaches removing the effects of catch selectivity, selection prior to the catch and environmental variation. Therefore, fishing most likely increased genetic variability for somatic growth in pike and presumably favoured an observed rapid evolutionary rebound after fishery relaxation. Inference about the mechanisms through which harvesting negatively affects population numbers and recovery should systematically be based on a measure of the exact form of selection. From a management perspective, disruptive harvesting necessitates combining a preservation of large individuals with moderate exploitation rates, and thus provides a comprehensive tool for sustainable exploitation of natural resources

El Nino Influence on Holocene Reef Accretion in Hawai'i

New observations of reef accretion from several locations show that in Hawai'i accretion during early to middle Holocene time occurred in areas where today it is precluded by the wave regime, suggesting an increase in wave energy. Accretion of coral and coralline algae reefs in the Hawaiian Islands today is largely controlled by wave energy. Many coastal areas in the main Hawaiian Islands are periodically exposed to large waves, in particular from North Pacific swell and hurricanes. These are of sufficient intensity to prevent modern net accretion as evidenced by the antecedent nature of the seafloor. Only in areas sheltered from intense wave energy is active accretion observed. Analysis of reef cores reveals patterns of rapid early Holocene accretion in several locations that terminated by middle Holocene time, ca. 5000 yr ago. Previous analyses have suggested that changes in Holocene accretion were a result of reef growth "catching up" to sea level. New data and interpretations indicate that the end of reef accretion in the middle Holocene may be influenced by factors in addition to sea level. Reef accretion histories from the islands of Kaua'i, O'ahu, and Moloka'i may be interpreted to suggest that a change in wave energy contributed to the reduction or termination of Holocene accretion by 5000 yr ago in some areas. In these cases, the decrease in reef accretion occurred before the best estimates of the decrease in relative sea-level rise during the mid-Holocene high stand of sea level in the main Hawaiian Islands. However, reef accretion should decrease following the termination of relative sea-level rise (ca. 3000 yr ago) if reef growth were "catching up" to sea level. Evidence indicates that rapid accretion occurred at these sites in early Holocene time and that no permanent accretion is occurring at these sites today. This pattern persists despite the availability of hard substrate suitable for colonization at a wide range of depths between -30 m and the intertidal zone. We infer that forcing other than relative sea-level rise has altered the natural ability to support reef accretion on Hawaiian insular shelves. The limiting factor in these areas today is wave energy. Numbers of both large North Pacific swell events and hurricanes in Hawai'i are greater during El Nino years. We infer that if these major reef-limiting forces were suppressed, net accretion would occur in some areas in Hawai'i that are now wave-limited. Studies have shown that El Nino/Southern Oscillation (ENSO) was significantly weakened during early-mid Holocene time, only attaining an intensity similar to the current one ca. 5000 yr ago. We speculate that this shift in ENSO may assist in explaining patterns of Holocene Hawaiian reef accretion that are different from those of the present and apparently not related to relative sea-level rise

FE-ANN based modeling of 3D simple reinforced concrete girders for objective structural health evaluation

Master of ScienceDepartment of Civil EngineeringHayder A. RasheedThe structural deterioration of aging infrastructure systems is becoming an increasingly important issue worldwide. To compound the issue, economic strains limit the resources available for repair or replacement of such systems. Over the past several decades, structural health monitoring (SHM) has proved to be a cost-effective method for detection and evaluation of damage in structures. Visual inspection and condition rating is one of the most commonly applied SHM techniques, but the effectiveness of this method suffers due to its reliance on the availability and experience of qualified personnel performing largely qualitative damage evaluations. The artificial neural network (ANN) approach presented in this study attempts to augment visual inspection methods by developing a crack-induced damage quantification model for reinforced concrete bridge girders that requires only the results of limited field measurements to operate. Simply-supported three-dimensional reinforced concrete T-beams with varying geometric, material, and cracking properties were modeled using Abaqus finite element (FE) analysis software. Up to five cracks were considered in each beam, and the ratios of stiffness between cracked and healthy beams with the same geometric and material parameters were measured at nine equidistant nodes along the beam. Two feedforward ANNs utilizing backpropagation learning algorithms were then trained on the FE model database with beam properties serving as inputs for both neural networks. The outputs for the first network consisted of the nodal stiffness ratios, and the sole output for the second ANN was a health index parameter, computed by normalizing the area under the stiffness ratio profile over the span length of the beam. The ANNs achieved excellent prediction accuracies with coefficients of determination (R²) exceeding 0.99 for both networks. Additional FE models were created to further assess the networks’ prediction capabilities on data not utilized in the training process. The ANNs displayed good prediction accuracies (R² > 0.8) even when predicting damage levels in beams with geometric, material, and cracking parameters dissimilar from those found in the training database. A touch-enabled user interface was developed to allow the ANN models to be utilized for on-site damage evaluations. The results of this study indicate that application of ANNs with FE modeling shows great promise in SHM for damage evaluation

Bent crystal spectrometer for both frequency and wavenumber resolved x-ray scattering at a seeded free-electron laser

We present a cylindrically curved GaAs x-ray spectrometer with energy resolution $\Delta E/E = 1.1\cdot 10^{-4}$ and wave-number resolution of $\Delta k/k = 3\cdot 10^{-3}$, allowing plasmon scattering at the resolution limits of the Linac Coherent Light Source (LCLS) x-ray free-electron laser. It spans scattering wavenumbers of 3.6 to $5.2/$\AA\ in 100 separate bins, with only 0.34\% wavenumber blurring. The dispersion of 0.418~eV/$13.5\,\mu$m agrees with predictions within 1.3\%. The reflection homogeneity over the entire wavenumber range was measured and used to normalize the amplitude of scattering spectra. The proposed spectrometer is superior to a mosaic HAPG spectrometer when the energy resolution needs to be comparable to the LCLS seeded bandwidth of 1~eV and a significant range of wavenumbers must be covered in one exposure