Lei Zhu – författare

This book will appeal to scientists and engineers who are concerned with the design of microwave wideband devices and systems. For advanced (ultra)-wideband wireless systems, the necessity and design methodology of wideband filters will be discussed with reference to the inherent limitation in fractional bandwidth of classical bandpass filters. Besides the detailed working principles, a large number of design examples are demonstrated, which can be easily followed and modified by the readers to achieve their own desired specifications. Therefore, this book is of interest not only to students and researchers from academia, but also to design engineers in industry. With the help of complete design procedures and tabulated design parameters, even those with little filter design experience, will find this book to be a useful design guideline and reference, which can free them from tedious computer-aided full-wave electromagnetic simulations. Among different design proposals, wideband bandpass filters based on the multi-mode resonator have demonstrated many unparalleled attractive features, including a simple design methodology, compact size, low loss and good linearity in the wide passband, enhanced out-of-band rejection, and easy integration with other circuits/antennas. A conventional bandpass filter works under single dominant resonant modes of a few cascaded transmission line resonators and its operating bandwidth is widened via enhanced coupling between the adjacent resonators. However, this traditional approach needs an extremely high coupling degree of coupled-lines while producing a narrow upper stopband between the dominant and harmonic bands. As a sequence, the desired dominant passband is restricted to an extent less than 60% in fractional bandwidth. To circumvent these issues and break with the tradition, a filter based on the multiple resonant modes was initially introduced in 2000 by the first author of this book. Based on this novel concept, a new class of wideband filters with fractional bandwidths larger than 60% has been successfully developed so far. This book, presents and characterizes a variety of multi-mode resonators with stepped-impedance or loaded-stub configurations using the matured transmission line theory for development of advanced microwave wideband filters.

This title provides a unique theoretical framework for multi-mode resonant antennas and different approaches to their implementation, with an emphasis on mode gauge functionality, a new concept for a clear identification and flexible control of all usable resonant modes in multi-mode resonant antenna design. The book commences by advancing a generalized odd-even mode theory as a general theoretical framework for resonant elementary antennas, offering new insights into the classical problem of coupling effects between antenna and transmission lines and helping reveal the operation mechanism of elementary antennas under multi-mode resonance. Then, the concept of "mode gauge" is developed and employed for wideband elementary antenna design by simultaneously exciting and tuning multiple resonant modes within a single radiator. Apart from theoretical explorations, the authors also provide analysis of up-to-date implementation of multi-mode resonant elementary antennas with different functionalities, including wideband antennas, circularly polarized antennas, multiband antennas, frequency scanning antennas and low-profile antennas. Academics, students and professional engineers at all levels will greatly benefit from the book and will be provided with historical background, state-of-the-art methodology, useful design tools and multiple applications of multi-mode resonant antennas.

This title provides a unique theoretical framework for multi-mode resonant antennas and different approaches to their implementation, with an emphasis on mode gauge functionality, a new concept for a clear identification and flexible control of all usable resonant modes in multi-mode resonant antenna design. The book commences by advancing a generalized odd-even mode theory as a general theoretical framework for resonant elementary antennas, offering new insights into the classical problem of coupling effects between antenna and transmission lines and helping reveal the operation mechanism of elementary antennas under multi-mode resonance. Then, the concept of "mode gauge" is developed and employed for wideband elementary antenna design by simultaneously exciting and tuning multiple resonant modes within a single radiator. Apart from theoretical explorations, the authors also provide analysis of up-to-date implementation of multi-mode resonant elementary antennas with different functionalities, including wideband antennas, circularly polarized antennas, multiband antennas, frequency scanning antennas and low-profile antennas. Academics, students and professional engineers at all levels will greatly benefit from the book and will be provided with historical background, state-of-the-art methodology, useful design tools and multiple applications of multi-mode resonant antennas.

This book presents and discusses strategies for the design and implementation of common-mode suppressed balanced microwave filters, including, narrowband, wideband, and ultra-wideband filtersThis book examines differential-mode, or balanced, microwave filters by discussing several implementations of practical realizations of these passive components. Topics covered include selective mode suppression, designs based on distributed and semi-lumped approaches, multilayer technologies, defect ground structures, coupled resonators, metamaterials, interference techniques, and substrate integrated waveguides, among others. Divided into five parts, Balanced Microwave Filters begins with an introduction that presents the fundamentals of balanced lines, circuits, and networks. Part 2 covers balanced transmission lines with common-mode noise suppression, including several types of common-mode filters and the application of such filters to enhance common-mode suppression in balanced bandpass filters. Next, Part 3 examines wideband and ultra-wideband (UWB) balanced bandpass filters with intrinsic common-mode suppression. Narrowband and dual-band balanced bandpass filters with intrinsic common-mode suppression are discussed in Part 4. Finally, Part 5 covers other balanced circuits, such as balanced power dividers and combiners, and differential-mode equalizers with common-mode filtering. In addition, the book: Explores a research topic of increasing interest due to the growing demand of balanced transmission lines and circuits in modern communication systemsIncludes contributions from prominent worldwide experts in the fieldProvides readers with the necessary knowledge to analyze and synthesize balanced filters and circuitsBalanced Microwave Filters is an important text for R&D engineers, professionals, and specialists working on the topic of microwave filters. Post graduate students and Masters students in the field of microwave engineering and wireless communications, especially those involved in courses related to microwave filters, and balanced filters and circuits will also find it to be a vital resource.

This book provides a comprehensive overview of various self-assemblies in liquid crystalline polymers and their electrical, optical, mechanical, and flame retardant properties.

This book systemically presents key concepts of multi-modal hashing technology, recent advances on large-scale efficient multimedia search and recommendation, and recent achievements in multimedia indexing technology.

This book systemically presents key concepts of multi-modal hashing technology, recent advances on large-scale efficient multimedia search and recommendation, and recent achievements in multimedia indexing technology.

The authors explain how to accomplish this by utilizing the advanced dynamic graph learning technique in the era of big data. After covering the key topics related to dynamic graph learning, the book discusses the recent advancements in the area.

The authors explain how to accomplish this by utilizing the advanced dynamic graph learning technique in the era of big data. After covering the key topics related to dynamic graph learning, the book discusses the recent advancements in the area.

This book provides a comprehensive examination of the interaction between Services of General Economic Interest (SGEI) and EU competition law, covering in particular Article 106 of the Treaty on the Functioning of the European Union (TFEU) and state aid rules. It also takes the telecommunications, postal service and transport sectors as case studies, taking into account the technological, economic and political backgrounds to these sectors.The area of SGEI has undergone fundamental developments over the past three decades and the most recent changes in the Lisbon Treaty, recognizing SGEI as a shared value and granting explicit competence to the EU, mark its constitutional significance. The key issue is how to balance economic values underlying competitive markets and non-economic public service values such as universal access to essential services. The essence of the question is the relationship between the market and the state. This controversial issue is addressed through acritical analysis of a number of landmark EU Court judgments and Commission decisions over the decades.Offering a clear appreciation of the evolution of the EU regulatory framework on SGEI that lays out the limits and boundaries within which the Member States define, organize and fund SGEI, the book is particularly aimed at academics with a research interest in the interaction between public services and EU competition law, but as it also demonstrates clearly how the application of EU competition law has transformed the public utilities sectors, it will be of interest to law makers, legal professionals and policy makers as well.Dr. Lei Zhu is a Research Associate at the Institute of International Law at Wuhan University in Wuhan, China. He studied at the Institute for Competition & Procurement Studies of the Bangor University Law School in Wales, United Kingdom, where he obtained his PhD in law in 2015.

This book provides a comprehensive examination of the interaction between Services of General Economic Interest (SGEI) and EU competition law, covering in particular Article 106 of the Treaty on the Functioning of the European Union (TFEU) and state aid rules. It also takes the telecommunications, postal service and transport sectors as case studies, taking into account the technological, economic and political backgrounds to these sectors.The area of SGEI has undergone fundamental developments over the past three decades and the most recent changes in the Lisbon Treaty, recognizing SGEI as a shared value and granting explicit competence to the EU, mark its constitutional significance. The key issue is how to balance economic values underlying competitive markets and non-economic public service values such as universal access to essential services. The essence of the question is the relationship between the market and the state. This controversial issue is addressed through acritical analysis of a number of landmark EU Court judgments and Commission decisions over the decades.Offering a clear appreciation of the evolution of the EU regulatory framework on SGEI that lays out the limits and boundaries within which the Member States define, organize and fund SGEI, the book is particularly aimed at academics with a research interest in the interaction between public services and EU competition law, but as it also demonstrates clearly how the application of EU competition law has transformed the public utilities sectors, it will be of interest to law makers, legal professionals and policy makers as well.Dr. Lei Zhu is a Research Associate at the Institute of International Law at Wuhan University in Wuhan, China. He studied at the Institute for Competition & Procurement Studies of the Bangor University Law School in Wales, United Kingdom, where he obtained his PhD in law in 2015.

This two-volume set, CCIS 2374 and CCIS 2375, constitutes the revised selected papers from the 37th International Conference on Computer Animation and Social Agents, CASA 2024, held in Wuhan, China, during June 5-7, 2024.The 60 papers presented in these two volumes were carefully reviewed and selected from 208 submissions. These papers focus on various aspects of Computer Animation and Social Agents, such as Motion Capture & Retargeting, Physics-based Animation, Vision-based Techniques, Behavioral Animation, Facial Animation, Image-based Animation, Virtual Humans, Crowd Simulation, AI-based Animation, Deep Learning methods, Virtual humans and avatars, and 3D Physiological Humans.

This two-volume set, CCIS 2374 and CCIS 2375, constitutes the revised selected papers from the 37th International Conference on Computer Animation and Social Agents, CASA 2024, held in Wuhan, China, during June 5-7, 2024.The 60 papers presented in these two volumes were carefully reviewed and selected from 208 submissions. These papers focus on various aspects of Computer Animation and Social Agents, such as Motion Capture & Retargeting, Physics-based Animation, Vision-based Techniques, Behavioral Animation, Facial Animation, Image-based Animation, Virtual Humans, Crowd Simulation, AI-based Animation, Deep Learning methods, Virtual humans and avatars, and 3D Physiological Humans.

Unsupervised domain adaptation (UDA) is a challenging problem in machine learning where the model is trained on a source domain with labeled data and tested on a target domain with unlabeled data. In recent years, UDA has received significant attention from the research community due to its applicability in various real-world scenarios. This book provides a comprehensive review of state-of-the-art UDA methods and explores new variants of UDA that have the potential to advance the field.The book begins with a clear introduction to the UDA problem and is mainly organized into four technical sections, each focused on a specific piece of UDA research. The first section covers criterion optimization-based UDA, which aims to learn domain-invariant representations by minimizing the discrepancy between source and target domains. The second section discusses bi-classifier adversarial learning-based UDA, which creatively leverages adversarial learning by conducting a minimax game between the feature extractor and two task classifiers. The third section introduces source-free UDA, a novel UDA setting that does not require any raw data from the source domain. The fourth section presents active learning for UDA, which combines domain adaptation and active learning to reduce the amount of labeled data needed for adaptation.This book is suitable for researchers, graduate students, and practitioners who are interested in UDA and its applications in various fields, primarily in computer vision. The chapters are authored by leading experts in the field and provide a comprehensive and in-depth analysis of the current UDA methods and new directions for future research. With its broad coverage and cutting-edge research, this book is a valuable resource for anyone looking to advance their knowledge of UDA.