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An online adaptive forecasting method of ARIMA time series /Sastri, Tep, January 1981 (has links)
No description available.
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Principal component analysis of time series /Stewart, J. Richard,1936- January 1970 (has links)
No description available.
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Time-Series Data Analysis in Biomedical ApplicationsWang, Yiping January 2024 (has links)
This thesis explores methods for analyzing biomedical time-series data, focusing on two distinct applications: audio-based cough detection and time-gate optimization in Fluorescence Lifetime Imaging Microscopy (FLIM).
The first section presents time-gate optimization algorithm for rapid lifetime determination (RLD) in FLIM applications. FLIM is an emerging imaging technique used to measure molecular interactions in biological samples. The developed algorithm focuses on optimizing the time gates to balance speed and accuracy, which is particularly beneficial under diverse noise conditions. By maximizing the signal-to noise ratio (SNR), the algorithm improves the precision of lifetime measurements, enabling efficient analysis of biological processes that require fast imaging rates, such as cellular metabolism and neurological activities.
The second section presents a machine learning algorithm for automated cough detection using Convolutional Recurrent Neural Networks (CRNNs). Leveraging advanced feature extraction techniques, such as Mel spectrograms, the algorithm effectively distinguishes cough events from other audio signals, achieving high accuracy. Its adaptability to varying noise conditions makes it ideal for real-time respiratory monitoring, with strong potential for integration into mobile health platforms and hospital systems. This work addresses the critical need for non-invasive, continuous monitoring tools for chronic cough, a condition that significantly affects quality of
life.
Both contributions highlight the potential of targeted time-series analysis to improve the accuracy, speed, and reliability of biomedical monitoring and imaging. By advancing methods for cough detection and fluorescence lifetime estimation, this thesis offers adaptable tools for broader biomedical applications, contributing to both healthcare diagnostics and biological research. / Thesis / Master of Applied Science (MASc)
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Scalable Stream Processing and Management for Time Series DataMousavi, Bamdad 15 June 2021 (has links)
There has been an enormous growth in the generation of time series data in the past decade. This trend is caused by widespread adoption of IoT technologies, the data generated by monitoring of cloud computing resources, and cyber physical systems. Although time series data have been a topic of discussion in the domain of data management for several decades, this recent growth has brought the topic to the forefront. Many of the time series management systems available today lack the necessary features to successfully manage and process the sheer amount of time series being generated today. In this today we stive to examine the field and study the prior work in time series management. We then propose a large system capable of handling time series management end to end, from generation to consumption by the end user. Our system is composed of open-source data processing frameworks. Our system has the capability to collect time series data, perform stream processing over it, store it for immediate and future processing and create necessary visualizations. We present the implementation of the system and perform experimentations to show its scalability to handle growing pipelines of incoming data from various sources.
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Graph-based Time-series Forecasting in Deep LearningChen, Hongjie 02 April 2024 (has links)
Time-series forecasting has long been studied and remains an important research task. In scenarios where multiple time series need to be forecast, approaches that exploit the mutual impact between time series results in more accurate forecasts. This has been demonstrated in various applications, including demand forecasting and traffic forecasting, among others. Hence, this dissertation focuses on graph-based models, which leverage the internode relations to forecast more efficiently and effectively by associating time series with nodes. This dissertation begins by introducing the notion of graph time-series models in a comprehensive survey of related models. The main contributions of this survey are: (1) A novel categorization is proposed to thoroughly analyze over 20 representative graph time-series models from various perspectives, including temporal components, propagation procedures, and graph construction methods, among others. (2) Similarities and differences among models are discussed to provide a fundamental understanding of decisive factors in graph time-series models. Model challenges and future directions are also discussed. Following the survey, this dissertation develops graph time-series models that utilize complex time-series interactions to yield context-aware, real-time, and probabilistic forecasting. The first method, Context Integrated Graph Neural Network (CIGNN), targets resource forecasting with contextual data. Previous solutions either neglect contextual data or only leverage static features, which fail to exploit contextual information. Its main contributions include: (1) Integrating multiple contextual graphs; and (2) Introducing and incorporating temporal, spatial, relational, and contextual dependencies; The second method, Evolving Super Graph Neural Network (ESGNN), targets large-scale time-series datasets through training on super graphs. Most graph time-series models let each node associate with a time series, potentially resulting in a high time cost. Its main contributions include: (1) Generating multiple super graphs to reflect node dynamics at different periods; and (2) Proposing an efficient super graph construction method based on K-Means and LSH; The third method, Probabilistic Hypergraph Recurrent Neural Network (PHRNN), targets datasets under the assumption that nodes interact in a simultaneous broadcasting manner. Previous hypergraph approaches leverage a static weight hypergraph, which fails to capture the interaction dynamics among nodes. Its main contributions include: (1) Learning a probabilistic hypergraph structure from the time series; and (2) Proposing the use of a KNN hypergraph for hypergraph initialization and regularization. The last method, Graph Deep Factors (GraphDF), aims at efficient and effective probabilistic forecasting. Previous probabilistic approaches neglect the interrelations between time series. Its main contributions include: (1) Proposing a framework that consists of a relational global component and a relational local component; (2) Conducting analysis in terms of accuracy, efficiency, scalability, and simulation with opportunistic scheduling. (3) Designing an algorithm for incremental online learning. / Doctor of Philosophy / Time-series forecasting has long been studied due to its usefulness in numerous applications, including demand forecasting, traffic forecasting, and workload forecasting, among others. In scenarios where multiple time series need to be forecast, approaches that exploit the mutual impact between time series results in more accurate forecasts. Hence, this dissertation focuses on a specific area of deep learning: graph time-series models. These models associate time series with a graph structure for more efficient and effective forecasting. This dissertation introduces the notion of graph time series through a comprehensive survey and analyzes representative graph time-series models to help readers gain a fundamental understanding of graph time series. Following the survey, this dissertation develops graph time-series models that utilize complex time-series interactions to yield context-aware, real-time, and probabilistic forecasting. The first method, Context Integrated Graph Neural Network (CIGNN), incorporates multiple contextual graph time series for resource time-series forecasting. The second method, Evolving Super Graph Neural Network (ESGNN), constructs dynamic super graphs for large-scale time-series forecasting. The third method, Probabilistic Hypergraph Recurrent Neural Network (PHRNN), designs a probabilistic hypergraph model that learns the interactions between nodes as distributions in a hypergraph structure. The last method, Graph Deep Factors (GraphDF), targets probabilistic time-series forecasting with a relational global component and a relational local model. These methods collectively covers various data characteristics and model structures, including graphs, super graph, and hypergraphs; a single graph, dual graphs, and multiple graphs; point forecasting and probabilistic forecasting; offline learning and online learning; and both small and large-scale datasets. This dissertation also highlights the similarities and differences between these methods. In the end, future directions in the area of graph time series are also provided.
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Statistical inference for some nonlinear time series models黃鎮山, Wong, Chun-shan. January 1998 (has links)
published_or_final_version / Statistics / Doctoral / Doctor of Philosophy
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Some topics in longitudinal data analysis and panel time seriesmodelsFu, Bo, 傅博. January 2003 (has links)
published_or_final_version / Statistics and Actuarial Science / Doctoral / Doctor of Philosophy
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On some nonparametric and semiparametric approaches to time series modelling夏應存, Xia, Yingcun. January 1999 (has links)
published_or_final_version / Statistics and Actuarial Science / Doctoral / Doctor of Philosophy
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On tests for threshold-type non-linearity in time series analysis吳文慧, Ng, Man-wai. January 2001 (has links)
published_or_final_version / Statistics and Actuarial Science / Master / Master of Philosophy
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A multivariate gamma model with applications to hydrologyStott, David N. January 1990 (has links)
No description available.
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