In recent years, we have witnessed a rapid expansion of using super-thin metasurfaces to manipulate light or electromagnetic wave in a subwavelength scale. However, most designs are confined to a passive scheme and monofunctional operation, which hinders considerably the promising applications of the metasurfaces. Specifically, the tunable and multifunctional metasurfaces enable to facilitate switchable functionalities and multiple functionalities which are extremely essential and useful for integrated optics and microwaves, well alleviating aforementioned issues. In this book, we introduce our efforts in exploring the physics principles, design approaches, and numerical and experimental demonstrations on the fascinating functionalities realized. We start by introducing in Chapter 2 the "merging" scheme in constructing multi-functional metadevices, paying particular attention to its shortcomings issues. Having understood the merits and disadvantages of the "merging" scheme, we then introduce in Chapter 3 another approach to realize bifunctional metadevices under linearly polarized excitations, working in both reflection and transmission geometries or even in the full space. As a step further, we summarizes our efforts in Chapter 4 on making multifunctional devices under circularly polarized excitations, again including designing principles and devices fabrications/characterizations. Starting from Chapter 5, we turn to introduce our efforts on using the "active" scheme to construct multifunctional metadevices under linearly polarized wave operation. Chapter 6 further concentrates on how to employ the tunable strategy to achieve helicity/frequency controls of the circularly polarized waves in reflection geometry. We finally conclude this book in Chapter 7 by presenting our perspectives on future directions of metasurfaces and metadevices.
In this dissertation, two new numerical approaches for hydraulic fracturing in tight reservoir were developed. A more physical-based numerical 3D-model was developed for simulating the whole hydraulic fracturing process including fracture propagation, closure and contact as well as proppant transport and settling. In this approach rock formation, pore and fracture systems were assembled together, in which hydro-mechanical coupling effect, proppant transport and settling as well as their influences on fracture closure and contact were fully considered. A combined FDM and FVM schema was used to solve the problem. Three applications by using the new approach were presented. The results illustrated the whole hydraulic fracturing process well and seemed to be logical, which confirmed the ability of the developed approach to model the in-situ hydraulic fracturing operation from injection start till fully closure. In order to investigate the orientation problem of hydraulic fracturing in tight reservoir, a new approach for simulating arbitrary fracture propagation and orientation in 2D was developed. It was solved by a hybrid schema of XFEM and FVM. Three numerical studies were illustrated, which proved the ability of the developed approach to solve the orientation problem in field cases.
Despite the recent development and interest in the photonics of metallic wire structures, the relatively simple concepts and physics often remain obscured or poorly explained to those who do not specialize in the field. Electromagnetic Behaviour of Metallic Wire Structures provides a clear and coherent guide to understanding these phenomena without excessive numerical calculations. Including both background material and detailed derivations of the various different formulae applied, Electromagnetic Behaviour of Metallic Wire Structures describes how to extend basic circuit theory relating to voltages, currents, and resistances of metallic wire networks to include situations where the currents are no longer spatially uniform along the wire. This lays a foundation for a deeper understanding of the many new phenomena observed in meta-electromagnetic materials. Examples of applications are included to support this new approach making Electromagnetic Behaviour of Metallic Wire Structures a comprehensive and self-contained volume suitable for use by specialists, non-specialist, researchers and professionals in other relevant fields and even students.
This is an open access book. This book, first of all, introduces the new unveiled Guangdong-Macao Intensive Cooperation Zone with details as a special mode of the regional collaborative development that is committed to be mutually beneficial to both sides with different political and economic systems. China's central authorities have recently issued a masterplan for constructing the Guangdong-Macao Intensive Cooperation Zone at Hengqin Island in September 2021. As China's first and last European colony and one of China’s two special administrative regions (SARs), Macao has developed the gambling industry seven times larger than that of Las Vegas. However, the problem of the homogeneous industrial structure and the urgent need to promote sustainable economic growth by regional cooperation have been important theoretical and practical issues discussed by scholars and policy-makers. The Guangdong-Macao Intensive Cooperation Zone (ICZ) is managed under special customs supervision between two boarder lines and expected to diversify Macao’s economy. Then, this book dissects the theory of regional synergistic development and its applications in a number of international comparative and cross-interdisciplinary case studies worldwide. Finally, from the perspective of land use, transportation connection, and social service, this book thoroughly explores the challenges and strategies to implement the new cooperation model within the framework of one country, two systems, two customs, and two currencies to achieve a win–win situation using updated first-hand data collected by literature review, case study, field survey, spatial analysis, and interview.
This book comprehensively documents the various types of karst collapse and related conceptual site models, before discussing these collapses in terms of their impacts on engineering and the environment. Featuring over 200 real-world photos to illustrate the variety of karst collapses and their consequences, the book also provides specific methods and techniques to prevent, investigate, monitor and remediate these collapses. Decades of experience with these collapses make it clear that addressing the related hazards requires a multi-disciplinary approach that integrates geomorphology, engineering geology, hydrology, hydrogeology, biology, geophysics, geochemistry, and risk assessment.
This book introduces the synthesis of functional mesoporous carbon-based films and their applications in energy systems. In the last decades, the consumption of fossil fuels has led to many problems such as the energy crisis and climate change. The rapidly increasing energy demands and environmental issues have attracted lots of attention to develop new functional materials for sustainable energy technology. Mesoporous carbon-based films show unique properties and have been regarded as a promising material applied in highly efficient energy storage and conversion systems. Interfacial assembly strategies are usually employed to construct such film devices. In this book, recent developments in synthesis of mesoporous carbon-based film devices through interfacial assembly strategies are illustrated. Additionally, the applications of mesoporous carbon-based film devices for electrochemical energy systems including batteries and electrocatalysis are introduced to demonstrate their potential, as well as describing the mechanisms to enhance the performance of these systems. Finally, some challenges and future outlooks are presented to inspire better development and contributions to this field in coming years. Given its scope, this book appeals to undergraduate students, graduate students, engineers, and researchers involved in related fields.
This book introduces readers to the main theories of phytoremediation and its application to arsenic-contaminated soils in China. The hyperaccumulation theories are introduced, including the use of hyperaccumulators to remove large amounts of arsenic without producing toxic symptoms. The use of synchrotron-based X-ray absorption fine structure radiation to disclose the hyperaccumulation mechanism – a method that makes it possible to detect the elements in plant tissues without destroying the sample – is introduced in detail. This book also includes practical application cases of phytoremediation, which are rarely found in the literature. Allowing readers to gain a thorough understanding of phytoremediation technology, and demonstrating its efficiency in cleaning arsenic-contaminated soils, the book offers a valuable asset for graduate students, lecturers, researchers and engineers in the field of soil remediation.
This book builds on the analyses of Eugene and Howard Odum and introduces the concept of systems ecology. Ecological emergy accounting represents a breakthrough because it allows researchers to integrate man-made capital and natural capital so that human and natural concerns can be addressed using a consistent system of units. This book develops an emergy accounting model that is suitable for describing urban systems, thereby providing a comprehensive picture of those systems. To make the theory concrete, the authors use China’s Macao Special Administrative Region as a case study, and compare the results for Macao with those of other urban ecosystems around the world in the fields of ecological economy, tourism, waste treatment, gambling industry, land reclamation and resource consumption etc. Dr. Kampeng Lei is an advisory senior technician at the Environmental Protection Bureau, Government of Macao, China; Shaoqi Zhou is a professor at the College of Environment and Energy, the South China University of Technology, and the Guizhou Academy of Sciences, China; Zhishi Wang is a professor at the Faculty of Science and Technology, the University of Macau, China.
The objective of this SpringerBrief is to present security architectures and incentive mechanisms to realize system availability for D2D communications. D2D communications enable devices to communicate directly, improving resource utilization, enhancing user’s throughput, extending battery lifetime, etc. However, due to the open nature of D2D communications, there are two substantial technical challenges when applied to large-scale applications, that is, security and availability which is demonstrated in this book. This SpringerBrief proposes a secure data sharing protocol, which merges the advantages of public key cryptography and symmetric encryption, to achieve data security in D2D communications. Furthermore, a joint framework involving both the physical and application layer security technologies is proposed for multimedia service over D2D communications thus the scalable security service can be achieved without changing the current communication framework. Additionally, as the system availability largely depends on the cooperation degree of the users, a graph-theory based cooperative content dissemination scheme is proposed to achieve maximal Quality of Experience (QoE) with fairness and efficiency. This SpringerBrief will be a valuable resource for advanced-level students and researchers who want to learn more about cellular networks.
This book covers C-Programming focussing on its practical side. Volume 2 deals mainly with composite data structures and their composition. An extensive use of figures and examples help to give a clear description of concepts and help the reader to gain a systematic understanding of the programming language.
First, the protagonist in the book, Lu Bu, was born in poverty, which doomed him to be out of touch with most intellectuals from the gentry. Because the discrimination against commoners by the gentry and the gate valve is very serious. For example, during the Northern and Southern Dynasties, the relatives of Emperor Wu of Song Wudi visited the cremation's house, and were met with cold reception and even insulted by the cremation, and Emperor Wu of could only submit to humiliation. This shows that the contradiction between the two sides is sharp.
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