Böcker i Springer Theses-serien

This book is about coexistence patterns in ensembles of globally coupled nonlinear oscillators. Coexistence patterns in this respect are states of a dynamical system in which the dynamics in some parts of the system differ significantly from those in other parts, even though there is no underlying structural difference between the different parts. In other words, these asymmetric patterns emerge in a self-organized manner. As our main model, we use ensembles of various numbers of Stuart-Landau oscillators, all with the same natural frequency and all coupled equally strongly to each other. Employing computer simulations, bifurcation analysis and symmetry considerations, we uncover the mechanism behind a wide range of complex patterns found in these ensembles. Our starting point is the creation of so-called chimeras, which are subsequently treated within a new and broader context of related states.

This book describes the first application at CMS of deep learning algorithms trained directly on low-level, ¿raw¿ detector data, or so-called end-to-end physics reconstruction. Growing interest in searches for exotic new physics in the CMS collaboration at the Large Hadron Collider at CERN has highlighted the need for a new generation of particle reconstruction algorithms. For many exotic physics searches, sensitivity is constrained not by the ability to extract information from particle-level data but by inefficiencies in the reconstruction of the particle-level quantities themselves. The technique achieves a breakthrough in the reconstruction of highly merged photon pairs that are completely unresolved in the CMS detector. This newfound ability is used to perform the first direct search for exotic Higgs boson decays to a pair of hypothetical light scalar particles H¿aa, each subsequently decaying to a pair of highly merged photons äyy, an analysis once thought impossible to perform. The book concludes with an outlook on potential new exotic searches made accessible by this new reconstruction paradigm.

This book introduces readers to the preparation of metal nanocrystals and its applications. In this book, an important point highlighted is how to design noble metal nanocrystals at the atomic scale for energy conversion and storage. It also focuses on the controllable synthesis of water splitting electrode materials including anodic oxygen evolution reaction (OER) and cathode hydrogen evolution reaction (HER) at the atomic level by defect engineering and synergistic effect. In addition, in-situ technologies and theoretical calculations are utilized to reveal the catalytic mechanisms of catalysts under realistic operating condition. The findings presented not only enrich research in the nano-field, but also support the promotion of national and international cooperation.

This book focuses on the development of novel functionalized organoboron compounds and those synthetic methods. High degrees of chemo-, regio-, and stereoselectivities of the borylation reactions are attained through catalyst design and optimization. Furthermore, the selectivity-determining mechanisms are analyzed with state-of-the-art DFT and other computational methods.In this book, the author synthesizes some multi-substituted alkenyl and allylic boronates via borylation reactions using a copper(I)/diboron catalyst system. Those compounds contain novel densely substituted and distorted structures, which have not been accessed by other methods. The high stereoselectivities are achieved by the optimization of the catalyst, especially the ligand. Some new ligands are also developed in this book. Furthermore, the derivatization of the borylation products is demonstrated to access the sterically demanding complex molecules. Also, the author performs computational analysis toreveal how the catalyst controls the selectivities. The deep insight into the reaction mechanism provides guides for rational catalyst design for not only copper(I) catalysis but also other transition metal catalysis. Thus, the content should be of interest to academic and industrial scientists in a wide range of areas.

This book presents an analytical framework for calculating the fracture toughness of generally layered beam structures with an elastically coupled response and hygrothermal stresses. The beam under study features several peculiarities: it consists of multiple layers of dissimilar materials, features bending-extension coupling, and contains residual hygrothermal stresses. Here, a generic analytical model is proposed to compute the energy release rate and the mode mixity. Mechanics of composite materials, crack closure integral, and energetic methods are among the theoretical tools employed for developing the model.A wealth of new closed-form expressions is presented, together with their validation through finite element analyses, which enables investigating various material systems and testing configurations. Experimentalists will find directions for the design and interpretation of delamination tests on laminated composites with uncommon stacking sequences. At the same time, theoreticians can exploit the analytical solution as a benchmark test for more refined analytical and numerical models. Furthermore, the book gives novel insights into the fracture behavior of a titanium-to-CFRP adhesive joint, which is intended for application in the hybrid laminar flow control of a future aircraft. It reports on experiments and theoretical analyses that help understand the behavior of this novel joint. All in all, this book offers extensive updates on methods for fracture analysis of materials with an elastically coupled behavior and residual stresses. It addresses students, researchers, and engineers alike.

This book investigates the physics of the discovered Higgs boson and additional Higgs bosons in the extended Higgs models which includes higher-order quantum corrections. While the 125 GeV Higgs boson was discovered, the structure of the Higgs sector is still a mystery. Since the Higgs sector determines the concrete realization of the Higgs mechanism, the study of its nature is one of the central interests in current and future high-energy physics. The book begins with a review of the standard model and the two-Higgs doublet model, which is one of the representatives of the extended Higgs models. Subsequently, we discuss the studies of the two-Higgs doublet model at the lowest order of perturbation. Following the lowest-order analysis, we study the higher-order electroweak corrections in Higgs physics. After reviewing the renormalization procedure and the higher-order corrections in the decays of the discovered Higgs boson, we discuss the higher-order corrections in theHiggs strahlung process from an electron-positron collision, the decays of the additional charged and CP-odd Higgs bosons in the two-Higgs doublet model. From the series of these studies, it is found that the nature of the Higgs sector can be widely investigated by future collider experiments.

This book reports on a comprehensive study on a novel high-power converter, i.e. a Modular Multilevel Converter with Interleaved Half-bridge Submodules (ISM-MMC). It describes in depth its average model, the operating principles, as well as a new control method and a hybrid modulation strategy that help to exploit the benefits of the interleaving scheme. The new power converter is particularly advantageous for high-current applications that require superb quality of input/output waveforms. Moreover, this book reports on a systematic study of the current balancing problem between parallel-connected units that commutate in non-simultaneous fashion. This is a typical issue in interleaved converters, however here it is analyzed for the first time in relation to MMC-based structures. Two control strategies are proposed to cope with this matter. By using a sensorless regulation scheme, the number of required current transducers has been minimized, reducing complexity, cost, and footprintof the hardware, while providing converter with a fast and accurate current balancing. This book also offers a comprehensive comparison between several practical designs of ISM-MMC and classical MMC for an ultra-fast electrical vehicle charger. All in all, it provides graduate students and researchers, as well as field engineers and professionals with extensive information and essential practical details on the state-of-the-art MMC and ISM-MMC design.

This book constructs a non-Bloch band theory and studies physics described by non-Hermitian Hamiltonian in terms of the theory proposed here.In non-Hermitian crystals, the author introduces the non-Bloch band theory which produces an energy spectrum in the limit of a large system size. The energy spectrum is then calculated from a generalized Brillouin zone for a complex Bloch wave number. While a generalized Brillouin zone becomes a unit circle on a complex plane in Hermitian systems, it becomes a circle with cusps in non-Hermitian systems. Such unique features of the generalized Brillouin zone realize remarkable phenomena peculiar in non-Hermitian systems. Further the author reveals rich aspects of non-Hermitian physics in terms of the non-Bloch band theory. First, a topological invariant defined by a generalized Brillouin zone implies the appearance of topological edge states. Second, a topological semimetal phase with exceptional points appears, The topological semimetal phase is unique to non-Hermitian systems because it is caused by the deformation of the generalized Brillouin zone by changes of system parameters. Third, the author reveals a certain relationship between the non-Bloch waves and non-Hermitian topology.

How planets form is one of the long-standing questions in astrophysics. In particular, formation scenarios of planetesimals which are kilometer-sized bodies and a precursor of planets are still unclear and under debate although some promising mechanisms have been proposed.This book highlight disk instabilities that have the potential to explain the origin of planetesimals. Using linear analyses and numerical simulations, it addresses how a disk evolves through the development of instabilities, and also presents a new instability driven by dust coagulation. As a result, the simulation demonstrates a scenario of planetesimal formation: A successive development of multiple instabilities triggers planetesimal formation in resulting dusty rings.

This book presents the observation and the control of spin-polarized electrons in Rashba thin films and topological insulators, including the first observations of a weak topological insulator (WTI) and a higher-order topological insulator (HOTI) in bismuth halides. It begins with a general review of electronic structures at the solid surface and mentions that an electron spin at a surface is polarized due to the Rashba effect or topological insulator states with strong spin-orbit coupling. Subsequently it describes the experimental techniques used to study these effects, that is, angle-resolved photoemission spectroscopy (ARPES). Further it moves its focus onto the experimental investigations, in which mainly two different systems-noble metal thin films with the Rashba effects and bismuth halides topological insulators-are used. The study of the first system discusses the role of wavefunctions in spin-splitting and demonstrates a scaling law for the Rashba effect in quantum well films for the first time. High-resolution spin-resolved ARPES plays a vital role in systematically trace the thickness-evolution of the effect. The study of the latter material is the first experimental demonstration of both a WTI and HOTI state in bismuth iodide and bismuth bromide, respectively. Importantly, nano-ARPES with high spatial resolution is used to confirm the topological surface states on the side surface of the crystal, which is the hallmark of WTIs.The description of the basic and recently-developed ARPES technique with spin-resolution or spatial-resolution, essential in investigating spin-polarized electrons at a crystal surface, makes the book a valuable source for researchers not only in surface physics or topological materials but also in spintronics and other condensed-matter physics.

This thesis presents research on novel laboratory-scale synchrotron X-ray sources based on inverse Compton scattering and applications of their X-ray radiation using the Munich Compact Light Source (MuCLS) as an example. It provides an introduction to the theory of this laser-electron interaction, laser resonators and X-ray interactions with matter. On this basis, upgrades to the laser system including the development of a new laser optic, X-ray beam stabilisation and two techniques for fast X-ray energy switching of inverse Compton sources are presented. On the application side, the beamline, designed and developed for the inverse Compton X-ray source at the MuCLS, is described before various techniques and applications are demonstrated at this laboratory-scale synchrotron X-ray facility. Among them are K-edge subtraction imaging, X-ray phase contrast imaging and X-ray absorption spectroscopy. Additionally, a new X-ray microscopy technique, called full-field structured-illuminationsuper-resolution X-ray transmission microscopy, is presented.Apart from research conducted at the MuCLS, this thesis contains an in-depth overview on the state of the art of the various types of inverse Compton X-ray sources that have been realised so far. Accordingly, this thesis may serve as a guide and reference work for researchers working with inverse Compton X-ray sources as well as future users of such devices.

This book offers a systematic study of control algorithms applied in the operation of solar membrane distillation (SMD) facilities. After a short introduction to membrane distillation systems powered by solar energy, it reports on the various stages of the development of a comprehensive operating strategy, based on modelling, control, and optimization techniques, which enables an improved operation of SMD plants helping the commercialization of the SMD technology. A special focus of the research was to maximize the distillate production of the MD modules while reducing their thermal energy consumption, being those two important weaknesses of the current technology, as well as their minimizing operating costs. The optimised operating strategies were tested in a real pilot plant located at Plataforma Solar de Almería (a dependency of the Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas, CIEMAT, of Spain). All in all, this thesis offers extensive information on control and modeling algorithms, and on their practical applications in solar membrane distillation plants.

This book highlights the most complete characterization of the Higgs boson properties performed to date in the "golden channel," i.e., decay into a pair of Z bosons which subsequently decay into four leptons. The data collected by the CMS experiment in the so-called Run-II data-taking period of the LHC are used to produce an extensive set of results that test in detail the predictions of the Standard Model.Given the remarkable predictive power of the SM when including the Higgs boson, possible new physics will require even more extensive studies at higher statistics. A massive upgrade of the detectors is necessary to maintain the current physics performance in the harsh environment of the High-Luminosity LHC (HL-LHC) project, expected to start by the end of 2027. The CMS Collaboration will replace the current endcap calorimeters with a High Granularity Calorimeter (HGCAL). The HGCAL will be the very first large-scale silicon-based imaging calorimeter ever employed in ahigh-energy physics experiment. This book presents the results of the analysis of the test beam data collected with the first large-scale prototype of the HGCAL. The results of this analysis are used to corroborate the final design of the HGCAL and its nominal physics performance expected for the HL-LHC operations.

The thesis tackles two distinct problems of great interest in gravitational mechanics ¿ one relativistic and one Newtonian. The relativistic one is concerned with the "first law of binary mechanics", a remarkably simple variational relation that plays a crucial role in the modern understanding of the gravitational two-body problem, thereby contributing to the effort to detect gravitational-wave signals from binary systems of black holes and neutron stars. The work reported in the thesis provides a mathematically elegant extension of previous results to compact objects that carry spin angular momentum and quadrupolar deformations, which more accurately represent astrophysical bodies than mere point particles. The Newtonian problem is concerned with the isochrone problem of celestial mechanics, namely the determination of the set of radial potentials whose bounded orbits have a radial period independent of the angular momentum. The thesis solves this problem completely ina geometrical way and explores its consequence on a variety of levels, in particular with a complete characterisation of isochrone orbits. The thesis is exceptional in the breadth of its scope and achievements. It is clearly and eloquently written, makes excellent use of images, provides careful explanations of the concepts and calculations, and it conveys the author¿s personality in a way that is rare in scientific writing, while never sacrificing academic rigor.

This book reports a study of a class of Dion-Jacobson-type layered perovskite oxides in which high oxide-ion conductivities in phases were discovered for the first time in the world. The oxide-ion conductors are important in various energy conversion devices and environmental protection applications such as solid-oxide fuel cells, oxygen gas sensors, oxygen separation membranes, and oxygen-based catalysts. The discoveries are based on a new screening method, called the bond valence method, combined with an original design concept. The present finding of high oxide-ion conductivity reported in the thesis suggested the potential of Dion-Jacobson phases as a platform to identify superior oxide-ion conductors.To understand what causes such high oxide-ion conductivities in these layered perovskite oxides, the author analyzed their crystal structures at high temperature and described the relationship between oxide-ion conductivities and their crystal structures. A deep understanding of the mechanisms of oxide-ion diffusivity at an atomic level in the Dion-Jacobson phases is clarified.The discovery of these materials, the new screening method, and the original design concept make possible the realization of many environment-friendly technologies. The findings in this thesis facilitate the possibilities for many novel applications that will help lead to a sustainable future.

This book reports on a comprehensive experimental characterization of the material, mechanical and dynamic properties of masonry infill walls. It analyses the critical parameters affecting their out-of-plane seismic behavior, including the effects of the panel support conditions, gravity load, and previous damage. Further, it offers an extensive review of infill masonry strengthening strategies and reports on the experimental assessment of various textile-reinforced mortar (TRM) strengthening solutions. It also presents the development, implementation and calibration of a numerical model to simulate the infill panels¿ seismic behavior, with the corresponding findings of various tests to assess the seismic vulnerability of an infilled RC structure. All in all, this outstanding PhD thesis offers a comprehensive review of masonry infill walls, and a timely overview of numerical and experimental methods for testing and preventing the out-of-plane seismic collapse of RC buildings.

This book offers a comprehensive study concerning the reliability of renewable electricity production in the Faroe Islands. The first part reports on a RoadMap with investments in generation, storage and transmission capacity. Multiple scenarios, considering different technologies, are analysed. Practical constraints like the local resource potential, power plant locations and sizes are discussed, as well as the potential of tidal power. The second part of the book describes dynamic simulations studies carried out to investigate grid stability of the power system on the isolated island of Suðuroy. The available information about governor and automatic voltage regulators of the synchronous generators was very limited, therefore different approaches were combined to parameterise and validate the dynamic models. All in all, this book offers extensive information concerning the transition of the Faroese power system into a 100% renewable system. It ispractice-oriented, and describes methods that can be applied to other power systems as well.

The absence of new physics at the TeV scale observed thus far at the Large Hadron Collider (LHC) motivates an increasing focus on searches for weakly-coupled new particles and exotic signatures. In particular, particles with macroscopic mean proper lifetimes, known as long-lived particles (LLPs), are of significant interest due to their ability to elude the majority of searches which rely on the assumption that Beyond Standard Model particles decay close to the primary interaction point. Many models which aim to solve various issues with the Standard Model (SM) introduce new particles with lifetimes that are either unconstrained, or even shown to prefer the macroscopic regime. These theories often point to the Higgs boson as a possible portal to new physics, with exotic Higgs decays being the primary phenomenological consequence and means of discovery. It is well motivated both from theory and experimental constraints to consider the scenario in which the particles produced in these exotic decays have macroscopic proper lifetimes and give rise to unique detector signatures.This work describes a search for exotic decays of the Higgs boson to two long-lived, neutral, spin-0 particles which subsequently decay to pairs of b quarks, giving the striking signature of displaced hadronic jets in the ATLAS inner detector. Several other ATLAS searches have probed this decay topology previously, excluding branching ratios of the Higgs boson to LLPs of more than 10% for proper lifetimes greater than 100mm. These searches relied on dedicated triggers designed to select events with LLPs decaying in the ATLAS calorimeter or muon spectrometer. The lack of an equivalent trigger for LLP decays in the ATLAS inner detector has been a limiting factor in probing LLP lifetimes less than 100mm. To circumvent the difficulty of triggering on LLP decays, the search presented in this thesis exploits the ZH associated production mode, relying on leptonic trigger signatures to select interesting events. This is the first search for Higgs boson decays into LLPs to exploit this analysis methodology and additionally makes use of several novel methods for both background rejection and background estimation.No excess over Standard Model predictions is observed, and upper limits are set on the branching ratio of the Higgs boson to LLPs . Depending on the mass of the LLP, branching ratios greater than 10% are excluded for lifetimes as small as 4mm and as large as 100mm, probing an important gap in the ATLAS exotic Higgs decay programme. In comparison to the previous searches for Higgs decays to LLPs, these are among the most stringent limits placed on this scenario, and for LLPs with masses below 40 GeV these results represent the strongest existing constraints on the branching ratio of the Higgs boson to LLPs in this lifetime regime.

This book explores the Higgs boson and its interactions with fermions, as well as the detector technologies used to measure it. The Standard Model of Particle Physics has been a groundbreaking theory in our understanding of the fundamental properties of the universe, but it is incomplete, and there are significant hints which require new physics. The discovery of the Higgs boson in 2012 was a substantial confirmation of the Standard Model, but many of its decay modes remain elusive. This book presents the latest search for Higgs boson decays into c-quarks using a proton-proton collision dataset collected by the ATLAS experiment at the Large Hadron Collider (LHC). This decay mode has yet to be observed and requires advanced machine learning algorithms to identify c-quarks in the experiment. The results provide an upper limit on the rate of Higgs boson decays to c-quarks and a direct measurement of the Higgs boson coupling strength to c-quarks. The book also discusses the future of particle physics and the need for significant improvements to the detector to cope with increased radiation damage and higher data rates at the High-Luminosity LHC. It presents the characterization of the ATLAS pixel detector readout chip for the inner detector upgrade (ITk). The chip was subjected to irradiations using X-rays and protons to simulate the radiation environment at the HL-LHC. The tests showed that all readout chip components, including the digital logic and analogue front-end, are sufficiently radiation-tolerant to withstand the expected radiation dose. Finally, this book describes monolithic pixel detectors as a possible technology for future pixel detectors. This book is ideal for individuals interested in exploring particle physics, the Higgs boson, and the development of silicon pixel detectors.

The task of signal detection is deciding whether signals of interest exist by using their observed data. Furthermore, signals are reconstructed or their key parameters are estimated from the observations in the task of signal recovery. Sparsity is a natural characteristic of most of signals in practice. The fact that multiple sparse signals share the common locations of dominant coefficients is called by joint sparsity. In the context of signal processing, joint sparsity model results in higher performance of signal detection and recovery. This book focuses on the task of detecting and reconstructing signals with joint sparsity. The main contents include key methods for detection of joint sparse signals and their corresponding theoretical performance analysis, and methods for joint sparse signal recovery and their application in the context of radar imaging.