This book, Volume 4 in the series, is dedicated to the relationship between laboratory spectroscopy, recording ever-more-complex spectra using increasingly powerful instruments benefiting from the latest technology, and the development of observation using instruments that are embedded in mobile probes or nanosatellites. The theoretical models described in Volumes 1, 2 and 3 are used in this volume, applying the cumulant theorem in the mean-field theory framework to interpret the near and mid-infrared spectra of symmetric top molecules, such as ammonia (NH3) and spherical molecules, such as methane (CH4). These molecules can be isolated in their gaseous form or subjected to the environmental constraints of a nano-cage (a substitution site, clathrate, fullerene or zeolite) or surfaces. These methods are not only valuable in the fields of environmental sciences, planetology and astrophysics, but also fit into the framework of data processing and the concept of Big Data.

This book is dedicated to the description and application of various different theoretical models to identify the near and mid-infrared spectra of symmetric and spherical top molecules in their gaseous form. Theoretical models based on the use of group theory are applied to rigid and non-rigid molecules, characterized by the phenomenon of tunneling and large amplitude motions. The calculation of vibration-rotation energy levels and the analysis of infrared transitions are applied to molecules of ammonia (NH3) and methane (CH4). The applications show how interactions at the molecular scale modify the near and mid-infrared spectra of isolated molecules, under the influence of the pressure of a nano-cage (the substitution site of a rare gas matrix, clathrate, fullerene or zeolite) or a surface, and allow us to identify the characteristics of the perturbing environment. This book provides valuable support for teachers and researchers but is also intended for engineering students, working research engineers and MasterÂs and doctorate students.

Subtractive sound synthesis is one of the most widely used techniques in electronic music and in many analog synthesizers since the early 1960s. It is based on a simple principle, but its operation is complex, involving many parameters. It can be enhanced by a variety of effects that give the sound its authenticity, and does not simply imitate musical instruments, but can also transcribe noises present in natural soundscapes or generate entirely synthetic sounds. Synthesizers and Subtractive Sound Synthesis 2 presents practical exercises, ranging from the fundamentals to advanced functionalities. Most of the sound effects applicable to subtractive synthesis are covered: vibrato, phaser, reverb, etc. The final chapters deal with polyphony and arpeggiator-sequences.

Capturing, recording and broadcasting the voice is often difficult. Many factors must be taken into account and achieving a true representation is much more complex than one might think. The capture devices such as the position of the singer(s) or narrator(s), the acoustics, atmosphere and equipment are just some of the physical aspects that need to be mastered. Then there is the passage through the analog or digital channel, which disrupts the audio signal, as well as the processes that are often required to enrich, improve or even transform the vocal timbre and tessitura. While in the past these processes were purely material, today digital technologies and software produce surprising results that every professional in recording and broadcasting should know how to master. Recording and Voice Processing 2 focuses on live and studio voice recordings. It presents the various pieces of hardware and software necessary for voice recording, and details possible sound channel configurations based on recording location. An actual recording, and its various constraints, is then considered, addressing the pitfalls to avoid and the strategies to use in order to achieve a satisfactory result. Different special effects (vocoder, auto-tune, Melodyne, etc.) that can be used on the voice, whether spoken or sung, are also presented.

This book presents a collection of independent mathematical studies, describing the analytical reduction of complex generic problems in the theory of scattering and propagation of electromagnetic waves in the presence of imperfectly conducting objects. Their subjects include: a global method for scattering by a multimode plane; diffraction by an impedance curved wedge; scattering by impedance polygons; advanced properties of spectral functions in frequency and time domains; bianisotropic media and related coupling expressions; and exact and asymptotic reductions of surface radiation integrals. The methods developed here can be qualified as analytical when they lead to exact explicit expressions, or semi-analytical when they drastically reduce the mathematical complexity of studied problems. Therefore, they can be used in mathematical physics and engineering to analyse and model, but also in applied mathematics to calculate the scattered fields in electromagnetism for a low computational cost.

Acoustics of Fluid Media 1 is intended for undergraduate students and engineering students, as well as graduate students and professionals in the industry who are increasingly faced with the need to consider acoustic constraints in the design of new products. The physical principles and theoretical foundations of acoustics in fluids are first developed, including reflection and refraction of plane and spherical waves. The book then introduces notions of signal processing applied to sound waves, followed by radiation from surface or volume acoustic sources and the use of Green’s functions, as well as the description of diffraction and scattering phenomena. The final chapters are devoted to sound propagation in ducts and room acoustics. Each chapter is accompanied by a limited number of exercises, ranging from the simple application of formulas to problems requiring a more advanced theoretical analysis or a numerical solution. Throughout the book, the theoretical results are illustrated with numerous figures obtained from measurements or numerical simulations resulting from the evaluation of complex formulas or from the use of a finite element solver.

Capturing, recording and broadcasting the voice is often difficult. Many factors must be taken into account and achieving a true representation is much more complex than one might think. The capture devices such as the position of the singer(s) or narrator(s), the acoustics, atmosphere and equipment are just some of the physical aspects that need to be mastered. Then there is the passage through the analog or digital channel, which disrupts the audio signal, as well as the processes that are often required to enrich, improve or even transform the vocal timbre and tessitura. While in the past these processes were purely material, today digital technologies and software produce surprising results that every professional in recording and broadcasting should know how to master. Recording and Voice Processing 1 addresses some general theoretical concepts. A history of recording and the physiology of the vocal apparatus are detailed in order to give the reader an understanding of the fundamental aspects of the subject. This volume also includes an advanced study of microphones, addressing their characteristics and typologies. The acoustic environment and its treatment are also considered in terms of the location of the sound capture - whether in a home studio, recording studio, live or natural environment - in order to achieve a satisfactory sound recording.

A newsletter for librarians, documentalists, and science information specialists.