35 research outputs found
A Neuro-Symbolic Approach for Real-World Event Recognition from Weak Supervision
Events are structured entities involving different components (e.g, the participants, their roles etc.) and their relations. Structured events are typically defined in terms of (a subset of) simpler, atomic events and a set of temporal relation between them. Temporal Event Detection (TED) is the task of detecting structured and atomic events within data streams, most often text or video sequences, and has numerous applications, from video surveillance to sports analytics. Existing deep learning approaches solve TED task by implicitly learning the temporal correlations among events from data. As consequence, these approaches often fail in ensuring a consistent prediction in terms of the relationship between structured and atomic events. On the other hand, neuro-symbolic approaches have shown their capability to constrain the output of the neural networks to be consistent with respect to the background knowledge of the domain. In this paper, we propose a neuro-symbolic approach for TED in a real world scenario involving sports activities. We show how by incorporating simple knowledge involving the relative order of atomic events and constraints on their duration, the approach substantially outperforms a fully neural solution in terms of recognition accuracy, when little or even no supervision is available on the atomic events
A Neuro-Symbolic Approach to Structured Event Recognition
Events are structured entities with multiple components: the event type, the participants with their roles, the outcome, the sub-events etc. A fully end-to-end approach for event recognition from raw data sequence, therefore, should also solve a number of simpler tasks like recognizing the objects involved in the events and their roles, the outcome of the events as well as the sub-events. Ontological knowledge about event structure, specified in logic languages, could be very useful to solve the aforementioned challenges. However, the majority of successful approaches in event recognition from raw data are based on purely neural approaches (mainly recurrent neural networks), with limited, if any, support for background knowledge. These approaches typically require large training sets with detailed annotations at the different levels in which recognition can be decomposed (e.g., video annotated with object bounding boxes, object roles, events and sub-events). In this paper, we propose a neuro-symbolic approach for structured event recognition from raw data that uses "shallow" annotation on the high-level events and exploits background knowledge to propagate this supervision to simpler tasks such as object classification. We develop a prototype of the approach and compare it with a purely neural solution based on recurrent neural networks, showing the higher capability of solving both the event recognition task and the simpler task of object classification, as well as the ability to generalize to events with unseen outcomes
A Neuro-Symbolic Approach for Non-Intrusive Load Monitoring
A requirement of Smart Grids is the ability to predict the energy consumption patterns of their users. In the residential domain, this is usually not feasible due to the inability of the grid to dialog with (legacy) domestic appliances. To overcome this issue Non Intrusive Load Monitoring (NILM) was introduced, a task in which a predictor is used to disaggregate household power consumption. Many of the newer approaches make use of Neural Networks to accomplish this task, due to their superior ability to detect patterns in temporal (thus sequential) data. These models unfortunately require a huge amount of data to achieve good performance, and have the tendency to overfit the training data, making them difficult to predict future consumptions. For these reasons, adapting them to optimally predict a (future) house's consumption requires expensive and often prohibitive data collection phases.
We propose a solution in the form of a neuro-symbolic framework that refines neural network predictions via a constrained optimization problem modelling the characteristics of the appliances of a house. This combined approach achieves superior performance with respect to the neural network alone over two out of five appliances and comparable results for the remaining ones, without requiring further training data
Interval Logic Tensor Networks
In this paper, we introduce Interval Real Logic (IRL), a two-sorted logic
that interprets knowledge such as sequential properties (traces) and event
properties using sequences of real-featured data. We interpret connectives
using fuzzy logic, event durations using trapezoidal fuzzy intervals, and fuzzy
temporal relations using relationships between the intervals' areas. We propose
Interval Logic Tensor Networks (ILTN), a neuro-symbolic system that learns by
propagating gradients through IRL. In order to support effective learning, ILTN
defines smoothened versions of the fuzzy intervals and temporal relations of
IRL using softplus activations. We show that ILTN can successfully leverage
knowledge expressed in IRL in synthetic tasks that require reasoning about
events to predict their fuzzy durations. Our results show that the system is
capable of making events compliant with background temporal knowledge
Determination of Polycyclic Aromatic Hydrocarbons in Tea Infusions Samples by High Performance Liquid Chromatography with Fluorimetric Detection
This study focuses on the contamination of 15 polycyclic aromatic hydrocarbons (PAHs), recommended by the US Environmental Protection Agency, in 10 tea brands distributed in Italy. Analyses were carried out with a procedure based on saponification, liquidliquid extraction, and PAHs determination by high performance liquid chromatography with fluorescence detector. A comparison with ultrasonic extraction in bath water was also reported. Contamination is expressed as the sum of analyzed PAHs and ranged between 347 and 4120 ng/L with a mean value of 1675 ng/L. PAHs with 3-4 rings were dominant with a contribution of 92%, while 7% and 1% were found for PAHs with 5 and 6 rings, respectively. Moreover, data revealed that three samples exceeded the EU 2008 criteria established for drinking water in which the sum of benzo[k]fluoranthene, benzo [b]fluoranthene, benzo [g,h,i]perylene, and indeno [1,2,3-cd]pyrene is considered (<100 ng/L) and two samples exceeded the 10 ng/L level allowed for benzo [a]pyrene
Combinatorial entropy behaviour leads to range selective binding in ligand-receptor interactions
From viruses to nanoparticles, constructs functionalized with multiple ligands display peculiar binding properties that only arise from multivalent effects. Using statistical mechanical modelling, we describe here how multivalency can be exploited to achieve what we dub range selectivity, that is, binding only to targets bearing a number of receptors within a specified range. We use our model to characterise the region in parameter space where one can expect range selective targeting to occur, and provide experimental support for this phenomenon. Overall, range selectivity represents a potential path to increase the targeting selectivity of multivalent constructs
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Polyculturalism Current evidence, future directions, and implementation possibilities for diverse youth
With increasing diversity across many societies, it is critical to understand how to promote positive intergroup interactions among diverse youth in educational and other settings. Polyculturalism – a concept from the discipline of history – has recently been studied in psychology as an approach to addressing diversity and an individual difference belief, namely endorsing that diverse groups have interacted and exchanged with each other, thus influencing each other’s cultures throughout history. Although polyculturalism has been studied with adults, evidence suggests it may have important implications for youth’s experiences with diversity, including in schools. In this chapter, the authors: review research on diverse youth in educational settings; review research on polyculturalism, which has been found to be associated with positive intergroup attitudes and behavioral intentions, including toward immigrants; identify needed future research on polyculturalism among youth; and discuss possible implementation of polyculturalism to support positive intergroup interactions among diverse youth
Supplemental Material - Systematic Review and Meta-Analyses of Effective Programs for Reducing Ageism Toward Older Adults
Supplemental Material for Systematic Review and Meta-Analyses of Effective Programs for Reducing Ageism Toward Older Adults by MaryBeth Apriceno, and Sheri R. Levy in Journal of Applied Gerontology</p