Bøger af Lei Chen

This book examines the recent trend of extending data dependencies to adapt to rich data types in order to address variety and veracity issues in big data. Readers will be guided through the full range of rich data types where data dependencies have been successfully applied, including categorical data with equality relationships, heterogeneous data with similarity relationships, numerical data with order relationships, sequential data with timestamps, and graph data with complicated structures. The text will also discuss interesting constraints on ordering or similarity relationships contained in novel classes of data dependencies in addition to those in equality relationships, e.g., considered in functional dependencies (FDs). In addition to exploring the concepts of these data dependency notations, the book investigates the extension relationships between data dependencies, such as conditional functional dependencies (CFDs) that extend conventional functional dependencies (FDs). This forms in the book a family tree of extensions, mostly rooted in FDs, that help illuminate the expressive power of various data dependencies. Moreover, the book points to work on the discovery of dependencies from data, since data dependencies are often unlikely to be manually specified in a traditional way, given the huge volume and high variety in big data. It further outlines the applications of the extended data dependencies, in particular in data quality practice. Altogether, this book provides a comprehensive guide for readers to select proper data dependencies for their applications that have sufficient expressive power and reasonable discovery cost. Finally, the book concludes with several directions of future studies on emerging data.

Due to measurement errors, transmission lost, or injected noise for privacy protection, uncertainty exists in the data of many real applications. However, query processing techniques for deterministic data cannot be directly applied to uncertain data because they do not have mechanisms to handle data uncertainty. Therefore, efficient and effective manipulation of uncertain data is a practical yet challenging research topic. In this book, we start from the data models for imprecise and uncertain data, move on to defining different semantics for queries on uncertain data, and finally discuss the advanced query processing techniques for various probabilistic queries in uncertain databases. The book serves as a comprehensive guideline for query processing over uncertain databases. Table of Contents: Introduction / Uncertain Data Models / Spatial Query Semantics over Uncertain Data Models / Spatial Query Processing over Uncertain Databases / Conclusion

This book constitutes the refereed proceedings of the 16th Asia-Pacific Conference APWeb 2014 held in Changsha, China, in September 2014. The 34 full papers and 23 short papers presented were carefully reviewed and selected from 134 submissions. The papers address research, development and advanced applications of large-scale data management, web and search technologies, and information processing.

The book discusses superconducting fault current limiters and their applications in power systems, exploring the principles, simulations and engineering practices, but focusing on systematic applications in traditional and renewable power systems. It provides in-depth studies on a number of major topics such as architecture of superconducting fault current limiter, device design, parameter optimization, prototype testing, co-ordination control and performance evaluation. It also describes multiple application cases of superconducting fault current limiters, which are applied in high voltage direct current transmission systems, active distribution networks, and micro-grids. Offering a comprehensive and systematic overview of practical issues, the book is intended for readers wanting to learn practical approaches for developing superconducting fault current limiters. It also appeals to researchers, engineers and graduate students in various fields, including high-temperature superconducting materials, power system transient stability, and control science and engineering.

This book constitutes the refereed proceedings of the 13th International Conference on Web-Age Information Management, WAIM 2012, held in Harbin, China in August 2012. The 32 revised full papers presented together with 10 short papers and three keynotes were carefully reviewed and selected from a total of 178 submissions. The papers are organized in topical sections on wireless sensor networks; data warehousing and data mining; query processing; spatial databases; similarity search and queries; XML and Web data; graph and uncertain data; distributed computing; data security and management; information extraction and integration; and social networks and modern Web services.

Divided into 14 chapters, the book covers deep learning, deep neural networks (DNNs), convolutional neural networks (CNNs), recurrent neural networks (RNNs), unsupervised learning, deep reinforcement learning, automated machine learning, device-cloud collaboration, deep learning visualization, and data preparation for deep learning.

This book presents state-of-the-art research advances in the field of biologically inspired cooperative control theories and their applications.

This book introduces readers to the application of orbital data on space objects in the contexts of conjunction assessment and space situation analysis, including theories and methodologies.