Introducing Formalism in Economics: The Growth Model of John von Neumann

The objective is to interpret John von Neumann's growth model as a decisive step of the forthcoming formalist revolution of the 1950s in economics. This model gave rise to an impressive variety of comments about its classical or neoclassical underpinnings. We go beyond this traditional criterion and interpret rather this model as the manifestation of von Neumann's involvement in the formalist programme of mathematician David Hilbert. We discuss the impact of Kurt Gödel’s discoveries on this programme. We show that the growth model reflects the pragmatic turn of the formalist programme after Gödel and proposes the extension of modern axiomatisation to economics..Von Neumann, Growth model, Formalist revolution, Mathematical formalism, Axiomatics

Validation of ankle strength measurements by means of a hand-held dynamometer in adult healthy subjects

Uniaxial Hand-Held Dynamometer (HHD) is a low-cost device widely adopted in clinical practice to measure muscle force. HHD measurements depend on operator’s ability and joint movements. The aim of the work is to validate the use of a commercial HHD in both dorsiflexion and plantarflexion ankle strength measurements quantifying the effects of HHD misplacements and unwanted foot’s movements on the measurements. We used an optoelectronic system and a multicomponent load cell to quantify the sources of error in the manual assessment of the ankle strength due to both the operator’s ability to hold still the HHD and the transversal components of the exerted force that are usually neglected in clinical routine. Results showed that foot’s movements and angular misplacements of HHD on sagittal and horizontal planes were relevant sources of inaccuracy on the strength assessment. Moreover, ankle dorsiflexion and plantarflexion force measurements presented an inaccuracy less than 2% and higher than 10%, respectively. In conclusion, the manual use of a uniaxial HHD is not recommend ed for the assessment of ankle plantarflexion strength; on the contrary, it can be allowed asking the operator to pay strong attention to the HHD positioning in ankle dorsiflexion strength measurements

Control mechanisms and perceived organizational support: exploring the relationship between new and traditional forms of control

Purpose: Taking into account the need to make a clearer distinction between traditional and new organizational controls, this paper aims to investigate similarities and differences between those two forms and explore the extent to which new forms of control can be operationalized from a quantitative point of view. Design/methodology/approach: Suggesting that new organizational controls can be understood also in light of quantitative paradigms, we develop and test a scale to measure the existence of these types of controls, examine its construct validity and evaluate its convergent validity. Findings: The theoretical dimensions of new controls have empirical correspondence. Input and behaviour controls are strongly associated with the promotion of values and beliefs in organizations. New controls become responsible for employees’ acceptance of companies’ management, an aspect measured by Perceived-Organizational-Support (POS)

Student experiences of peer review marking of team projects

Peer review of students is a partial response to critics of group work who cite drawbacks of "free riders" and de-motivation. It is often used to motivate and focus students on their own development within a group work setting. Pressures of time, budget and student numbers often obviate deeper study of alternative assessment techniques. The study reported in this paper, made possible by an HEA grant, allowed for analysis of a peer review mechanism that had been operating for a number of years alongside a new web-based system. The paper reviews criticisms of peer review techniques in existing literature and outlines how student experiences of peer review were researched. Qualitative outcomes are discussed alongside an analysis of quantitative data from the systems used. Key conclusions from this research are that the data collection method made no significant difference to the reported student experiences of peer review or to the peer review marks. The findings update and strengthen previous literature and provide important new insights into the emotional perspective of students. The findings from this research are being used to aid development of the webbased system and to establish 'good practice' guidance on the deployment of this valuable and innovative technique

Technique for abrasive cutting of thick-film conductors for hybrid circuits

Abrasive jet technique, producing prototype conductor networks for thick-film hybrid microcircuits, does not require screening and fixing procedures. Pantograph engraver is used to perform abrasive cutting of the conductor network

Coexistence of Magneto-Rotational and Jeans Instabilities in an Axisymmetric Nebula

We analyze the magneto-rotational instability (MRI) effects on gravitational collapse and its influence on the instability critical scale. In particular, we study an axisymmetric nonstratified differentially rotating cloud, embedded in a small magnetic field, and we perform a local linear stability analysis, including the self gravity of the system. We demonstrate that the linear evolution of the perturbations is characterized by the emergence of an anisotropy degree of the perturbed mass densities. Starting with spherical growing overdensities, we see that they naturally acquire an anisotropy of order unity in their shape. Despite the linear character of our analysis, we infer that such a seed of anisotropy can rapidly grow in a nonlinear regime, leading to the formation of filament-like structures. However, we show how such an anisotropy is essentially an intrinsic feature of the Jean instability, and how MRI only plays a significant role in fixing the critical scale of the mode spectrum. We then provide a characterization of the present analysis in terms of the cosmological setting, in order to provide an outlook of how the present results could concern the formation of large-scale structures across the Universe.Comment: 8 pages, 4 figure

A 90 nm CMOS 16 Gb/s Transceiver for Optical Interconnects

Interconnect architectures which leverage high-bandwidth optical channels offer a promising solution to address the increasing chip-to-chip I/O bandwidth demands. This paper describes a dense, high-speed, and low-power CMOS optical interconnect transceiver architecture. Vertical-cavity surface-emitting laser (VCSEL) data rate is extended for a given average current and corresponding reliability level with a four-tap current summing FIR transmitter. A low-voltage integrating and double-sampling optical receiver front-end provides adequate sensitivity in a power efficient manner by avoiding linear high-gain elements common in conventional transimpedance-amplifier (TIA) receivers. Clock recovery is performed with a dual-loop architecture which employs baud-rate phase detection and feedback interpolation to achieve reduced power consumption, while high-precision phase spacing is ensured at both the transmitter and receiver through adjustable delay clock buffers. A prototype chip fabricated in 1 V 90 nm CMOS achieves 16 Gb/s operation while consuming 129 mW and occupying 0.105 mm^2

Transient response for interaction of two dynamic bodies

During the launch sequence of any space vehicle complicated boundary interactions occur between the vehicle and the launch stand. At the start of the sequence large forces exist between the two; contact is then broken in a short but finite time which depends on the release mechanism. The resulting vehicle response produces loads which are very high and often form the design case. It is known that the treatment of the launch pad as a second dynamic body is significant for an accurate prediction of launch response. A technique was developed for obtaining loads generated by the launch transient with the effect of pad dynamics included. The method solves uncoupled vehicle and pad equations of motion. The use of uncoupled models allows the simulation of vehicle launch in a single computer run. Modal formulation allows a closed-form solution to be written, eliminating any need for a numerical integration algorithm. When the vehicle is on the pad the uncoupled pad and vehicle equations have to be modified to account for the constraints they impose on each other. This necessitates the use of an iterative procedure to converge to a solution, using Lagrange multipliers to apply the required constraints. As the vehicle lifts off the pad the coupling between the vehicle and the pad is eliminated point by point until the vehicle flies free. Results obtained by this method were shown to be in good agreement with observed loads and other analysis methods. The resulting computer program is general, and was used without modification to solve a variety of contact problems

Instrumental trouble: a queer organology of Hugh Davies’s found instruments

Organology, the study of musical instruments, has traditionally concentrated on the documentation of instruments: their history, roles in culture, and classification. However, as post-modern, feminist, and post-colonial perspectives have questioned some of the assumptions inherent in historiographical, ethnographic, and positivist endeavours because of their part in reproducing hegemonic ideologies, re-thinking organology and thus developing a richer account of musical instruments has become an urgent task. With this regard a queer perspective in organology, in particular informed by Judith Butler’s theories of “gender trouble,” is crucial in agitating normative beliefs, values, and attitudes that underpin notions of instrumental identity, interaction, and meaning. A queer organology becomes especially significant in the critical engagement with musical instruments like those invented by the British composer, performer, and inventor Hugh Davies (1943-2005), and in particular his entirely found, amplified, new musical instruments. This is because the challenges to traditional instrumental ontologies, the “instrumental trouble” that these instruments pose, reveal the boundaries of conventional organological approaches and methodologies, which are unsuitable in capturing their full significance. Deploying Butler’s concepts of recognition, performativity, and subversion in their study can thus represent an effective strategy in the development of a coherent critique of Davies’s instruments, but also in offering an opportunity to further the understanding of the fundamental importance that musical instruments play in the articulations of music, as part of what may be called an “instrumental turn.