Books published by Mdpi AG

This book shows the potential of entropy and information theory in forecasting, including both theoretical developments and empirical applications. The contents cover a great diversity of topics, such as the aggregation and combination of individual forecasts, the comparison of forecasting performance, and the debate concerning the tradeoff between complexity and accuracy. Analyses of forecasting uncertainty, robustness, and inconsistency are also included, as are proposals for new forecasting approaches. The proposed methods encompass a variety of time series techniques (e.g., ARIMA, VAR, state space models) as well as econometric methods and machine learning algorithms. The empirical contents include both simulated experiments and real-world applications focusing on GDP, M4-Competition series, confidence and industrial trend surveys, and stock exchange composite indices, among others. In summary, this collection provides an engaging insight into entropy applications for forecasting, offering an interesting overview of the current situation and suggesting possibilities for further research in this field.

The global increase in air travel will require commercial vehicles to be more efficient than ever before. Advanced engine hot section materials are a key technology required to keep fuel consumption and emission to a minimum in next-generation gas turbines. Ceramic matrix composites (CMCs) are the most promising material to revolutionize gas turbine hot section materials technology because of their excellent highΓÇÉtemperature properties. Rapid surface recession due to volatilization by water vapor is the Achilles heel of CMCs. Environmental barrier coatings (EBCs) is an enabling technology for CMCs, since it protects CMCs from water vapor. The first CMC component entered into service in 2016 in a commercial engine, and more CMC components are scheduled to follow within the next few years. One of the most difficult challenges to CMC components is EBC durability, because failure of EBC leads to a rapid reduction in CMC component life. Key contributors to EBC failure include recession, oxidation, degradation by calciumΓÇÉaluminumΓÇÉmagnesium silicates (CMAS) deposits, thermal and thermoΓÇÉmechanical strains, particle erosion, and foreign object damage (FOD). Novel EBC chemistries, creative EBC designs, and robust processes are required to meet EBC durability challenges. Engine-relevant testing, characterization, and lifing methods need to be developed to improve EBC reliability. The aim of this Special Issue is to present recent advances in EBC technology to address these issues. In particular, topics of interest include but are not limited to the following: ΓÇóNovel EBC chemistries and designs; ΓÇóProcessing including plasma spray, suspension plasma spray, solution precursor plasma spray, slurry process, PS-PVD, EB-PVD, and CVD; ΓÇóTesting, characterization, and modeling; ΓÇóLifing.

This book is comprised of different paper contributions published in "Remote Sensing", under the Special Issue "Radar Imaging in Challenging Scenarios from Smart and Flexible Platforms," for which we served as guest editors. According to the general objective of the Special Issue, the papers included provide a good survey of newborn imaging radar systems, such as synthetic aperture radar (SAR) and ground penetrating radar (GPR), which are designed to operate in challenging scenarios. The latter includes the cases of forward-looking radar or lunar penetrating radar and smart and flexible platforms, such as small airplanes, drones or helicopters. The radar systems described in the book cover a wide range of the microwave spectrum, starting from the VHF band up to the X-band. In addition to the description of newborn systems, the Special Issue includes an important survey of data processing techniques aimed at achieving accurate radar imaging under complex acquisition geometries and/or monitoring scenarios. We thank the Editorial Office of Remote Sensing and all the authors and reviewers for their professional and hard work. Without their excellent contributions, the Special Issue, and thus this book, would not have been possible.

The complexity of radiation damage effects in materials that are used in various irradiation environments stems from the fundamental particle-solid interactions and the subsequent damage recovery dynamics after the collision cascades, which involves multiple length and time scales. Adding to this complexity are the transmuted impurities that are unavoidable from accompanying nuclear processes. Helium is one such impurity that plays an important and unique role in controlling the microstructure and properties of materials used in fast fission reactors, plasma-facing and structural materials in fusion devices, spallation neutron target designs, actinides, tritium-containing materials, and nuclear waste. Their ultra-low solubility in virtually all solids forces He atoms to self-precipitate into small bubbles that become nucleation sites for further void growth under radiation-induced vacancy supersaturations, resulting in material swelling and high-temperature He embrittlement, as well as surface blistering under low-energy and high-flux He bombardment. This Special Issue, "Radiation Damage in Materials-Helium Effects", contains review articles and full-length papers on new irradiation material research activities and novel material ideas using experimental and/or modeling approaches. These studies elucidate the interactions of helium with various extreme environments and tailored nanostructures, as well as their impact on microstructural evolution and material properties.

This Special Issue covers several recent advances in robotic devices applied to motor rehabilitation and assistance. The Special Issue has collected eight outstanding papers covering different aspects of assistance robotics and biosensors. The selected contributions cover several main topics related to assistance robotics, from the control of myoelectric prostheses to the rehabilitation and assistance of the lower and upper limbs.