University of Miami
Real-Time Detection and Prediction of Relative Motion of Moving Objects in Autonomous Driving
Polpitiya, Lalintha G. (The MathWorks, Inc. ) | Premaratne, Kamal (University of Miami)
Autonomous driving vehicles must have the ability to identify and predict behaviors of surrounding moving objects (e.g., other vehicles, cyclists, and pedestrians) in real-time. This is especially true in urban environments, where interactions become more complex due to high volumes of traffic. The work in this paper harnesses the Dempster-Shafer (DS) theoretic framework's ability to capture and account for various types of evidence uncertainty to develop a robust event detection and prediction model, which is appropriately calibrated to account for the underlying uncertainty so that it may be employed to arrive at a more informed decision.
Modeling Temporal Tonal Relations in Polyphonic Music Through Deep Networks With a Novel Image-Based Representation
Chuan, Ching-Hua (University of North Florida) | Herremans, Dorien (University of Miami)
We propose an end-to-end approach for modeling polyphonic music with a novel graphical representation, based on music theory, in a deep neural network. Despite the success of deep learning in various applications, it remains a challenge to incorporate existing domain knowledge in a network without affecting its training routines. In this paper we present a novel approach for predictive music modeling and music generation that incorporates domain knowledge in its representation. In this work, music is transformed into a 2D representation, inspired by tonnetz from music theory, which graphically encodes musical relationships between pitches. This representation is incorporated in a deep network structure consisting of multilayered convolutional neural networks (CNN, for learning an efficient abstract encoding of the representation) and recurrent neural networks with long short-term memory cells (LSTM, for capturing temporal dependencies in music sequences). We empirically evaluate the nature and the effectiveness of the network by using a dataset of classical music from various composers. We investigate the effect of parameters including the number of convolution feature maps, pooling strategies, and three configurations of the network: LSTM without CNN, LSTM with CNN (pre-trained vs. not pre-trained). Visualizations of the feature maps and filters in the CNN are explored, and a comparison is made between the proposed tonnetz-inspired representation and pianoroll, a commonly used representation of music in computational systems. Experimental results show that the tonnetz representation produces musical sequences that are more tonally stable and contain more repeated patterns than sequences generated by pianoroll-based models, a finding that is directly useful for tackling current challenges in music and AI such as smart music generation.
Progressive Prediction of Student Performance in College Programs
Xu, Jie (University of Miami) | Han, Yuli (Tsinghua University) | Marcu, Daniel (University of Southern California) | Schaar, Mihaela van der (University of California, Los Angeles)
Accurately predicting students' future performance based on their tracked academic records in college programs is crucial for effectively carrying out necessary pedagogical interventions to ensure students' on-time graduation. Although there is a rich literature on predicting student performance in solving problems and studying courses using data-driven approaches, predicting student performance in completing college programs is much less studied and faces new challenges, mainly due to the diversity of courses selected by students and the requirement of continuous tracking and incorporation of students' evolving progresses. In this paper, we develop a novel algorithm that enables progressive prediction of students' performance by adapting ensemble learning techniques and utilizing education-specific domain knowledge. We prove its prediction performance guarantee and show its performance improvement against benchmark algorithms on a real-world student dataset from UCLA.
Modeling and Experimentation Framework for Fuzzy Cognitive Maps
Espinosa, Maikel Leon (University of Miami) | Ruiz, Gonzalo Napoles (Hasselt University)
Many papers describe the use of Fuzzy Cognitive Maps as a modeling/representation technique for real-life scenariosโ simulation or prediction. However, not many real software implementations are described neither found. In this proposal the authors describe a modeling and experimentation framework where realistic problems can be recreated using Fuzzy Cognitive Maps as a knowledge representation form. Design elements, and descriptions of the algorithms that have been incorporated into the software, and hybridized with Fuzzy Cognitive Maps, are presented in this paper. Case studies were conducted and are illustrated with the intention of demonstrating the success and practical value of the general approach together with the implementation tool.
Humanoid Robots and Spoken Dialog Systems for Brief Health Interventions
Abeyruwan, Saminda (University of Miami) | Baral, Ramesh (Florida International University) | Yasavur, Ugan (Florida International University) | Lisetti, Christine (Florida International University) | Visser, Ubbo (University of Miami)
We combined a spoken dialog system that we developed to deliver brief health interventions with the fully autonomous humanoid robot (NAO).ย The dialog system is based on a framework facilitating Markov decision processes (MDP). It is optimized using reinforcement learning (RL) algorithms with data we collected from real user interactions. The system begins to learn optimal dialog strategies for initiative selection and for the type of confirmations that it uses during theinteraction.ย The health intervention, delivered by a 3D character instead of the NAO, has already been evaluated, with positive results in terms of task completion, ease of use, and future intention to use the system. ย The current spoken dialog system for the humanoid robot is a novelty and exists so far as a proof ofconcept.
Modeling and Predicting Popularity Dynamics via Reinforced Poisson Processes
Shen, Huawei (Chinese Academy of Sciences) | Wang, Dashun (IBM Thomas J. Watson Research Center) | Song, Chaoming (University of Miami) | Barabรกsi, Albert-Lรกszlรณ (Northeastern University)
Indeed, to the best of our knowledge, we lack forgotten over time (Wu and Humberman 2007). For example, a probabilistic framework to model and predict the popularity videos on YouTube or stories on Digg gain their popularity dynamics of individual items. The reason behind this is by striving for views or votes (Szabo and Huberman partly illustrated in Figure 1, suggesting that the dynamical 2010); papers increase their visibility by competing for citations processes governing individual items appear too noisy to be from new papers (Ren et al. 2010; Wang, Song, and amenable to quantification. Barabรกsi 2013); tweets or Hashtags in Twitter become more In this paper, we model the stochastic popularity dynamics popular as being retweeted (Hong, Dan, and Davison 2011) using reinforced Poisson processes, capturing simultaneously and so do webpages as being attached by incoming hyperlinks three key ingredients: fitness of an item, characterizing (Ratkiewicz et al. 2010). An ability to predict the popularity its inherent competitiveness against other items; a general of individual items within a dynamically evolving system temporal relaxation function, corresponding to the aging not only probes our understanding of complex systems, in the ability to attract new attentions; and a reinforcement but also has important implications in a wide range of domains, mechanism, documenting the well-known "rich-get-richer" from marketing and traffic control to policy making phenomenon. The benefit of the proposed model is threefold: and risk management. Despite recent advances of empirical (1) It models the arrival process of individual attentions methods, we lack a general modeling framework to predict directly in contrast to relying on aggregated popularity the popularity of individual items within a complex evolving time series; (2) As a generative probabilistic model, it can be system.
Converting Instance Checking to Subsumption: A Rethink for Object Queries over Practical Ontologies
Xu, Jia (University of Miami) | Visser, Ubbo (University of Miami) | Kabuka, Mansur (University of Miami)
Instance checking is considered a central service for data retrieval from description logic (DL) ontologies. In this paper, we propose a revised most specific concept (MSC) method for DL SHI}, which converts instance checking into subsumption problems. This revised method can generate small concepts that are specific-enough to answer a given query, and allow reasoning to explore only a subset of the ABox data to achieve efficiency. Experiments show effectiveness of our proposed method in terms of concept size reduction and the improvement in reasoning efficiency.
Generating Pictorial Storylines Via Minimum-Weight Connected Dominating Set Approximation in Multi-View Graphs
Wang, Dingding (University of Miami) | Li, Tao (Florida International University) | Ogihara, Mitsunori (University of Miami)
This paper introduces a novel framework for generating pictorial storylines for given topics from text and image data on the Internet. Unlike traditional text summarization and timeline generation systems, the proposed framework combines text and image analysis and delivers a storyline containing textual, pictorial, and structural information to provide a sketch of the topic evolution. A key idea in the framework is the use of an approximate solution for the dominating set problem. Given a collection of topic-related objects consisting of images and their text descriptions, a weighted multi-view graph is first constructed to capture the contextual and temporal relationships among these objects. Then the objects are selected by solving the minimum-weighted connected dominating set problem defined on this graph. Comprehensive experiments on real-world data sets demonstrate the effectiveness of the proposed framework.