Mechanical Transformations: the Active Roles of Machines In British Industrial-era Writings

Industrialization defined nineteenth-century Britain, bringing large-scale changes to the social order. Observers perceived that machines stood at the heart of these changes as much as inventors, manufacturers, and operatives, if not more so. A range of writers expressed their awareness of the transformative power of technology by endowing machines with a sense of life and influence according to four broad characterizations: machines as instruments of civilizational advancement disguised as mundane tools, organic life, bringers of order, and near-mythical embodiments of power. Critics of industry coopted such lofty language and turned it on its head to depict machines as destructive, sometimes monstrous forces. More broadly, nineteenth-century sources indicate a perception of machines as channels for the human will, for better and worse, performing tasks that human beings cannot accomplish alone. A study of NASA’s dramatic retirement of the Cassini space probe illustrates how nineteenth-century characterizations of machines have persisted into the twenty-first century. In conclusion, the influential roles in which industrial-era authors cast machines derived from their power and seeming autonomy as well as from their close relationship to human beings and human ambition. As automation advances in the twenty-first century, the tendency to personify machines will also persist in forms that evolve with time and technological change

Optimization of Enzymatic Logic Gates and Networks for Noise Reduction and Stability

Biochemical computing attempts to process information with biomolecules and biological objects. In this work we review our results on analysis and optimization of single biochemical logic gates based on enzymatic reactions, and a network of three gates, for reduction of the "analog" noise buildup. For a single gate, optimization is achieved by analyzing the enzymatic reactions within a framework of kinetic equations. We demonstrate that using co-substrates with much smaller affinities than the primary substrate, a negligible increase in the noise output from the logic gate is obtained as compared to the input noise. A network of enzymatic gates is analyzed by varying selective inputs and fitting standardized few-parameters response functions assumed for each gate. This allows probing of the individual gate quality but primarily yields information on the relative contribution of the gates to noise amplification. The derived information is then used to modify experimental single gate and network systems to operate them in a regime of reduced analog noise amplification.Comment: 7 pages in PD

Static and Dynamic Nonlinearity of A/D Converters

The dynamic range of broadband digital system is mostly limited by harmonics and spurious arising from ADC nonlinearity. The nonlinearity may be described in several ways. The distinction between static and dynamic contributions has strong theoretical motivations but it is difficult to independently measure these contributions. A more practical approach is based upon analysis of the complex spectrum, which is well defined, easily measured, and may be used to optimize the ADC working point and to somehow characterize both static and dynamic nonlinearity. To minimize harmonics and spurious components we need a sufficient level of input noise (dither), which destroys the periodicity at multistage pipelined ADC, combined with a careful analysis of the different sources of nonlinearity

Realization and Properties of Biochemical-Computing Biocatalytic XOR Gate Based on Signal Change

We consider a realization of the XOR logic gate in a system involving two competing biocatalytic reactions, for which the logic-1 output is defined by these two processes causing a change in the optically detected signal. A model is developed for describing such systems in an approach suitable for evaluation of the analog noise amplification properties of the gate and optimization of its functioning. The initial data are fitted for gate quality evaluation within the developed model, and then modifications are proposed and experimentally realized for improving the gate functioning