Stochastic Technical Stability Test of a Passenger Railroad Car Crossing a Turnout

This article presents a definition of stochastic technical stability that was applied to test a mathematical model of a passenger railroad car crossing a turnout with the speed exceeding 160 km/h. Stability defined in this way allows testing of Lyapunov’s stability with disturbances from the track and for a nonlinear system. The STS test of a nonlinear mathematical model of a passenger car was carried out by perturbing the motion of the mathematical model with irregularities originating from the track gauge change and wheelset motion in the direction transverse to the track axis. The main aim of this paper was to determine the influence of various factors and technical conditions on the assessment of the stability of various means of transport. The analysis presented can be used to assess the dynamics of electric vehicles, whose mechanical parameters differ from those of combustion vehicles at present. The area of stable motion in the Lyapunov sense was defined using the STS method. Simulations were performed to determine the trajectory of the wheelset transverse motion. The probability of finding the wheelset in the stable motion area in relation to the rail for a single-point contact was determined. In practice, this is a one-point contact of the wheel with the rail. Conclusions from the conducted research are presented.

The Cochlear Implant as an Epistemic Thing

This chapter examines the translations and (de)stabilizations of the cochlear implant, a subcutaneous prosthesis that is subject to ethical and judicial controversies. By looking at medical, social, and scientific contexts, the CI will be described as a technical object ascribed with certain attributes providing technical stability in those contexts that treat it and practice it as a scientific fact, a “technical thing.” Scientific communities stabilize technical things by rigorously excluding attributes of the “social.” However, the CI is designed to enable participation, to “gap” the supposed “disability” of not being able to hear, attributing a certain instability to it. The chapter will theoretically and methodologically approach such processes of (de)stabilization and transformation by making use of ANT and Hans-Jörg Rheinbergers concept of technical and epistemic things. This will be illustrated by analyzing certain discourses used as illustrations for the successful communication between implanted children and their parents in practical guides for parents with deaf children.

The Cochlear Implant as an Epistemic Thing

This chapter examines the translations and (de)stabilizations of the cochlear implant, a subcutaneous prosthesis that is subject to ethical and judicial controversies. By looking at medical, social, and scientific contexts, the CI will be described as a technical object ascribed with certain attributes providing technical stability in those contexts that treat it and practice it as a scientific fact, a “technical thing.” Scientific communities stabilize technical things by rigorously excluding attributes of the “social.” However, the CI is designed to enable participation, to “gap” the supposed “disability” of not being able to hear, attributing a certain instability to it. The chapter will theoretically and methodologically approach such processes of (de)stabilization and transformation by making use of ANT and Hans-Jörg Rheinbergers concept of technical and epistemic things. This will be illustrated by analyzing certain discourses used as illustrations for the successful communication between implanted children and their parents in practical guides for parents with deaf children.