Samira Pouyanfar

Computational Health Informatics in the Big Data Age: A Survey

The explosive growth and widespread accessibility of digital health data have led to a surge of research activity in the healthcare and data sciences fields. The conventional approaches for health data management have achieved limited success as they are incapable of handling the huge amount of complex data with high volume, high velocity, and high variety. This article presents a comprehensive overview of the existing challenges, techniques, and future directions for computational health informatics in the big data age, with a structured analysis of the historical and state-of-the-art methods. We have summarized the challenges into four Vs (i.e., volume, velocity, variety, and veracity) and proposed a systematic data-processing pipeline for generic big data in health informatics, covering data capturing, storing, sharing, analyzing, searching, and decision support. Specifically, numerous techniques and algorithms in machine learning are categorized and compared. On the basis of this material, we identify and discuss the essential prospects lying ahead for computational health informatics in this big data age.

Semantic Event Detection Using Ensemble Deep Learning

Numerous deep learning architectures have been designed for a variety of tasks in the past few years. However, it is almost impossible for one model to work well for all kinds of scenarios and datasets. Therefore, we present an ensemble deep learning framework in this paper, which not only decreases the information loss and over-fitting problems caused by single models, but also overcomes the imbalanced data issue in multimedia big data. First, a suite of deep learning algorithms are utilized for deep feature selection. Thereafter, an enhanced ensemble algorithm is developed based on the performance of each single Support Vector Machine classifier on each deep feature set. We evaluate our proposed ensemble deep learning framework on a large and highly imbalanced video dataset containing natural disaster events. Experimental results demonstrate the effectiveness of the proposed framework for semantic event detection, and show how it outperforms several state-of-the-art deep learning architectures, as well as handcrafted features integrated with ensemble and non-ensemble algorithms.

Semantic Concept Detection Using Weighted Discretization Multiple Correspondence Analysis for Disaster Information Management

Multimedia semantic concept detection is an emerging research area in recent years. One of the prominent challenges in multimedia concept detection is data imbalance. In this study, a multimedia data mining framework for interesting concept detection in videos is presented. First, the Minimum Description Length (MDL) discretization algorithm is extended to handle the imbalanced data. Thereafter, a novel Weighted Discretization Multiple Correspondence Analysis (WD-MCA) algorithm based on the Multiple Correspondence Analysis (MCA) approach is proposed to maximize the correlation between the feature value pairs and concept classes by incorporating the discretization information captured from the MDL module. The proposed framework achieves promising performance to videos containing disaster events. The experimental results demonstrate the effectiveness of the WD-MCA algorithm, specifically for imbalanced datasets, compared to several existing methods.

Correlation-Based Deep Learning for Multimedia Semantic Concept Detection

Nowadays, concept detection from multimedia data is considered as an emerging topic due to its applicability to various applications in both academia and industry. However, there are some inevitable challenges including the high volume and variety of multimedia data as well as its skewed distribution. To cope with these challenges, in this paper, a novel framework is proposed to integrate two correlation-based methods, Feature-Correlation Maximum Spanning Tree (FC-MST) and Negative-based Sampling (NS), with a well-known deep learning algorithm called Convolutional Neural Network (CNN). First, FC-MST is introduced to select the most relevant low-level features, which are extracted from multiple modalities, and to decide the input layer dimension of the CNN. Second, NS is adopted to improve the batch sampling in the CNN. Using NUS-WIDE image data set as a web-based application, the experimental results demonstrate the effectiveness of the proposed framework for semantic concept detection, comparing to other well-known classifiers.

An efficient deep residual-inception network for multimedia classification

Deep learning has led to many breakthroughs in machine perception and data mining. Although there are many substantial advances of deep learning in the applications of image recognition and natural language processing, very few work has been done in video analysis and semantic event detection. Very deep inception and residual networks have yielded promising results in the 2014 and 2015 ILSVRC challenges, respectively. Now the question is whether these architectures are applicable to and computationally reasonable in a variety of multimedia datasets. To answer this question, an efficient and lightweight deep convolutional network is proposed in this paper. This network is carefully designed to decrease the depth and width of the state-of-the-art networks while maintaining the high-performance. The proposed deep network includes the traditional convolutional architecture in conjunction with residual connections and very light inception modules. Experimental results demonstrate that the proposed network not only accelerates the training procedure, but also improves the performance in different multimedia classification tasks.

Automatic Video Event Detection for Imbalance Data Using Enhanced Ensemble Deep Learning

With the explosion of multimedia data, semantic event detection from videos has become a demanding and challenging topic. In addition, when the data has a skewed data distribution, interesting event detection also needs to address the data imbalance problem. The recent proliferation of deep learning has made it an essential part of many Artificial Intelligence (AI) systems. Till now, various deep learning architectures have been proposed for numerous applications such as Natural Language Processing (NLP) and image processing. Nonetheless, it is still impracticable for a single model to work well for different applications. Hence, in this paper, a new ensemble deep learning framework is proposed which can be utilized in various scenarios and datasets. The proposed framework is able to handle the over-fitting issue as well as the information losses caused by single models. Moreover, it alleviates the imbalanced data problem in real-world multimedia data. The whole framework includes a suite of deep learning feature extractors integrated with an enhanced ensemble algorithm based on the performance metrics for the imbalanced data. The Support Vector Machine (SVM) classifier is utilized as the last layer of each deep learning component and also as the weak learners in the ensemble module. The framework is evaluated on two large-scale and imbalanced video datasets (namely, disaster and TRECVID). The extensive experimental results illustrate the advantage and effectiveness of the proposed framework. It also demonstrates that the proposed framework outperforms several well-known deep learning methods, as well as the conventional features integrated with different classifiers.

Multimedia Big Data Analytics: A Survey

With the proliferation of online services and mobile technologies, the world has stepped into a multimedia big data era. A vast amount of research work has been done in the multimedia area, targeting different aspects of big data analytics, such as the capture, storage, indexing, mining, and retrieval of multimedia big data. However, very few research work provides a complete survey of the whole pine-line of the multimedia big data analytics, including the management and analysis of the large amount of data, the challenges and opportunities, and the promising research directions. To serve this purpose, we present this survey, which conducts a comprehensive overview of the state-of-the-art research work on multimedia big data analytics. It also aims to bridge the gap between multimedia challenges and big data solutions by providing the current big data frameworks, their applications in multimedia analyses, the strengths and limitations of the existing methods, and the potential future directions in multimedia big data analytics. To the best of our knowledge, this is the first survey that targets the most recent multimedia management techniques for very large-scale data and also provides the research studies and technologies advancing the multimedia analyses in this big data era.

Domain Knowledge Assisted Data Processing for Florida Public Hurricane Loss Model (Invited Paper)

Catastrophes have caused tremendous damages in human history and triggered record high post-disaster relief from the governments. The research of catastrophic modeling can help estimate the effects of natural disasters like hurricanes, floods, surges, and earthquakes. In every Atlantic hurricane season, the state of Florida in the United States has the potential to suffer economic and human losses from hurricanes. The Florida Public Hurricane Loss Model (FPHLM), funded by the Florida Office of Insurance Regulation, has assisted Florida and the residential insurance industry for more than a decade. How to process big data for historical hurricanes and insurance companies remains a challenging research topic for cat models. In this paper, the FPHLMs novel integrated domain knowledge assisted big data processing system is introduced and its effectiveness of data processing error prevention is presented.

IF-MCA: Importance Factor-Based Multiple Correspondence Analysis for Multimedia Data Analytics

Multimedia concept detection is a challenging topic due to the well-known class imbalance issue, where the data instances are distributed unevenly across different classes. This problem becomes even more prominent when the minority class that contains an extremely small proportion of the data represents the concept of interest as has occurred in many real-world applications such as frauds in banking transactions and goal events in soccer videos. Traditional data mining approaches often have difficulty handling largely skewed data distributions. To address this issue, in this paper, an importance-factor (IF)-based multiple correspondence analysis (MCA) framework is proposed to deal with the imbalanced datasets. Specifically, a hierarchical information gain analysis method, which is inspired by the decision tree algorithm, is presented for critical feature selection and IF assignment. Then, the derived IF is incorporated with the MCA algorithm for effective concept detection and retrieval. The comparison results in video concept detection using the disaster dataset and the soccer dataset demonstrate the effectiveness of the proposed framework.

Integrated execution framework for catastrophe modeling

Home insurance is a critical issue in the state of Florida, considering that residential properties are exposed to hurricane risk each year. To assess hurricane risk and project insured losses, the Florida Public Hurricane Loss Model (FPHLM) funded by the states insurance regulatory agency was developed. The FPHLM is an open and public model that offers an integrated complex computing framework that can be described in two phases: execution and validation. In the execution phase, all major components of FPHLM (i.e., data pre-processing, Wind Speed Correction (WSC), and Insurance Loss Model (ILM)) are seamlessly integrated and sequentially carried out by following a coordination workflow, where each component is modeled as an execution element governed by the centralized data-transfer element. In the validation phase, semantic rules provided by domain experts for individual component are applied to verify the validity of model output. This paper presents how the model efficiently incorporates the various components from multiple disciplines in an integrated execution framework to address the challenges that make the FPHLM unique.