The Body as Musical Instrument

This chapter explores the possibility of thinking of the human body as musical instrument. It builds on the philosophy of phenomenology to discuss body schemata that might be considered “instrumental” and discusses the diversity of bodies proposed by body theory to consider the incorporation of digital technology. Concepts of embodied interaction from the scientific field of human–computer interaction are discussed with an eye toward musical application. The history of gestural musical instruments is presented, from the Theremin to instruments from the STEIM studio. The text then focuses on the use of physiological signals to create music, from historical works of Lucier and Rosenboom to recent performances by the authors. The body as musical instrument is discussed in a dynamic of coadaptation between performer and instrument in different configurations of body and technology

Ominous: Playfulness and emergence in a performance for biophysical music

This article tackles the issue of playfulness in biosignal-based performance with digital musical instruments. The practical context is that of an interactive sound sculpture performance, entitled 'Ominous', for the 'Xth Sense', a biophysical musical instrument. This work posits that a prominent quality of the body physiology is its emergence. Developed by cultural theorist Brian Massumi, the notion of bodily emergence is useful to inform playfulness in musical performance for it can be used to understand a performer's body as being continuously changed by physiological and autonomic processes. This article presents a strategy for musical interaction that uses the relations in time and intensity of two biosignals to make the musical instrument adapt to the performer's physiological states. This strategy is put into practice by implementing a system that, drawing upon findings in biomedical engineering, brings together biosignal feature extraction, multidimensional mapping and digital neural networks

Configuring Corporeality: Performing bodies, vibrations and new musical instruments.

How to define the relationship of human bodies, sound and technological instruments in musical performance? This enquiry investigates the issue through an iterative mode of research. Aesthetic and technical insights on sound and body art performance with new musical instruments combine with analytical views on technological embodiment in philosophy and cultural studies. The focus is on corporeality: the physiological, phenomenological and cultural basis of embodied practices. The thesis proposes configuration as an analytical device and a blueprint for artistic creation. Configuration defines the relationship of the human being and technology as one where they affect each other's properties through a continuous, situated negotiation. In musical performance, this involves a performer's intuition, cognition, and sensorimotor skills, an instrument's material, musical and computational properties, and sound's vibrational and auditive qualities. Two particular kinds of configuration feature in this enquiry. One arises from an experiment on the effect of vibration on the sensorimotor system and is fully developed through a subsequent installation for one visitor at a time. The other emerges from a scientific study of gesture expressivity through muscle physiological sensing and is consolidated into an ensuing body art performance for sound and light. Both artworks rely upon intensely intimate sensorial and physical experiences, uses and abuses of the performer's body and bioacoustic sound feedback as a material force. This work contends that particular configurations in musical performance reinforce, alter or disrupt societal criteria against which human bodies and technologies are assessed. Its contributions are: the notion of configuration, which affords an understanding of human-machine co-dependence and its politics; two sound-based artworks, joining and expanding musical performance and body art; two experiments, and their hardware and software tools, providing insights on physiological computing methods for corporeal human-computer interaction

Simulation Techniques for Design and Control of a Waste Heat Recovery System in Marine Natural Gas Propulsion Applications

Waste Heat Recovery (WHR) marine systems represent a valid solution for the ship energy eciency improvement, especially in Liquefied Natural Gas (LNG) propulsion applications. Compared to traditional diesel fuel oil, a better thermal power can be recovered from the exhaust gas produced by a LNG-fueled engine. Therefore, steam surplus production may be used to feed a turbogenerator in order to increase the ship electric energy availability without additional fuel consumption. However, a correct design procedure of the WHR steam plant is fundamental for proper feasibility analysis, and from this point of view, numerical simulation techniques can be a very powerful tool. In this work, the WHR steam plant modeling is presented paying attention to the simulation approach developed for the steam turbine and its governor dynamics. Starting from a nonlinear system representing the whole dynamic behavior, the turbogenerator model is linearized to carry out a proper synthesis analysis of the controller, in order to comply with specific performance requirements of the power grid. For the considered case study, simulation results confirm the validity of the developed approach, aimed to test the correct design of the whole system in proper working dynamic conditions

MARINE CYCLOIDAL PROPULSION MODELLING FOR DP APPLICATIONS

This paper presents the numerical modelling of a cycloidal propeller in freerunning conditions together with its possible applications. The model calibration is carried out by comparing simulation results with experimental data of an existing cycloidal unit. The achieved results support the main strength of the proposed simulation approach: propeller fluid dynamics is not calculated, avoiding demanding computations that would not allow an effective simulation of the whole propulsion plant. As a case study, the cycloidal propulsors model is used for the thruster allocation assessment of the Dynamic Positioning (DP) system of a surface vessel, originally equipped with traditional propellers. Then, the steady-state performance analysis of the DP system is carried out in terms of a comparison between the two distinct propulsion configurations

Hysteresis Modeling in Iron-Dominated Magnets Based on a Multi-Layered Narx Neural Network Approach

A full-fledged neural network modeling, based on a Multi-layered Nonlinear Autoregressive Exogenous Neural Network (NARX) architecture, is proposed for quasi-static and dynamic hysteresis loops, one of the most challenging topics for computational magnetism. This modeling approach overcomes drawbacks in attaining better than percent-level accuracy of classical and recent approaches for accelerator magnets, that combine hybridization of standard hysteretic models and neural network architectures. By means of an incremental procedure, different Deep Neural Network Architectures are selected, fine-tuned and tested in order to predict magnetic hysteresis in the context of electromagnets. Tests and results show that the proposed NARX architecture best fits the measured magnetic field behavior of a reference quadrupole at CERN. In particular, the proposed modeling framework leads to a percent error below 0.02% for the magnetic field prediction, thus outperforming state of the art approaches and paving a very promising way for future real time applications

Bacterial inactivation/sterilization by argon plasma treatment on contaminated titanium implant surfaces: in vitro study

Background: Surface treatment by argon plasma is widely used as the last step of the manufacturing process of titanium implant fixtures before their sterilization by gamma rays. The possibility of using such a technology in the daily clinical practice is particularly fascinating. The aim of the present study was to assess the effects of the argon plasma treatment on different titanium implant surfaces previously exposed in vitro to bacterial contamination. Material and Methods: Sterile c.p. titanium implant discs with turned (T, Sa: 0.8μm), sandblasted/acid-etched (SAE, Sa: 1.3μm) and titanium plasma sprayed (TPS, Sa: 3.0μm) surface were used in this study. A strain of Aggregatibacter actinomycetemcomitans ATCC3718 was grown at 37°C under anaerobic conditions for 24 h and then transferred on six discs for each of the three surface types. After 24 hours, a half of the contaminated discs (control group) were directly used to evaluate the colony forming units (CFUs). The other half of the contaminated discs (test group) were treated in an argon plasma chamber for 12 minutes at room temperature prior to be analyzed for CFU counting. All assays were performed using triplicate samples of each material in 3 different experiments. Results: When the CFU counting was carried out on control discs, a total of 1.50x106±1.4x105, 1.55x106±7.07x104 and 3.15x106±2.12x105 CFU was respectively assessed for T, SAE and TPS discs, without statistically significant differences among the three surfaces. On the contrary, any trace of bacterial contamination was assessed for titanium discs treated in the argon plasma chamber prior to be analyzed, irrespectively to the implant surface tested. Conclusions: Within the limit of this study, reported data suggested that the argon plasma technology could be efficiently used to decontaminate/sterilize previously infected titanium implant surfaces