Production of trans-Neptunian binaries through chaos-assisted capture

The recent discovery of binary objects in the Kuiper-belt opens an invaluable window into past and present conditions in the trans-Neptunian part of the Solar System. For example, knowledge of how these objects formed can be used to impose constraints on planetary formation theories. We have recently proposed a binary-object formation model based on the notion of chaos-assisted capture. Here we present a more detailed analysis with calculations performed in the spatial (three-dimensional) three- and four-body Hill approximations. It is assumed that the potential binary partners are initially following heliocentric Keplerian orbits and that their relative motion becomes perturbed as these objects undergo close encounters. First, the mass, velocity, and orbital element distribu- tions which favour binary formation are identified in the circular and elliptical Hill limits. We then consider intruder scattering in the circular Hill four-body problem and find that the chaos-assisted capture mechanism is consistent with observed, apparently randomly distributed, binary mutual orbit inclinations. It also predicts asymmetric distributions of retrograde versus prograde orbits. The time-delay induced by chaos on particle transport through the Hill sphere is analogous to the formation of a resonance in a chemical reaction. Implications for binary formation rates are considered and the 'fine-tuning' problem recently identified by Noll et al. (2007) is also addressed.Comment: submitted to MNRA

Designing a personal information transaction object

© 2016 IEEE. As mobile and wearable technologies grow in popularity, ever-increasing volumes of valuable, fine-grained personal information are generated as people go about their daily lives. This information may be exchanged by individuals for "free" services, but there is currently no widely adopted means by which individuals can benefit financially from their personal information. To address this problem we consider a Primary Personal Information Market (PPIM) - a market on which individuals can be financially compensated in exchange for access to their personal information. We draw on Design Science and Market Engineering to justify design choices for a permissions-based Personal Information Transaction Object (PITO), a commodity which could be successfully traded on a Primary Personal Information Market

Designing a Primary Personal Information Market as an Industry Platform: a Service Innovation Approach

It is well recognised that personal data have intrinsic value to B2C companies. However, there are no widely adopted means by which individuals can benefit financially from the personal data they generate. Furthermore, there is a substantial lack of empirical research on markets for online personal data. Nevertheless, prior work has shown that a Primary Personal Information Market (PPIM) is a viable solution to the problem of monetising personal data. This paper explores how a PPIM could be conceptualised and designed as an Industry Platform. Using an integrated Service Innovation Method (iSIM) we incorporate into our design a multi-sided personal information business model to facilitate commercialisation. An initial prototype is developed and its utility from a data product consumer’s perspective is evaluated using semi-structured interviews with industry practitioners. We find that a PPIM conceptualised as an industry platform has significant commercial appeal and that it resolves a number of objections raised in response to previous designs

Reporting on the Annual Report

Annual reports provide an important source of information for investors. The SEC guidance to companies that requires forward-looking discussions of events is far from uniform but a constructive step in providing information

Evidence of an Alternative Currency for Altruism in Laboratory-Based Experiments

Research shows that altruistic behaviours arise in varying social situations in line with different theories of causes of such behaviours. However most research uses financial costs only, which makes our understanding of altruism currently limited. This study presents findings of three experiments that use a novel and simple laboratory-based task that measures altruism based on the amount of time participants are willing to spend as a cost to help others. This task assessed two specific theories; altruistic punishment (Experiments 1 & 2) and empathy-altruism (Experiment 3). All experiments showed that the task was successful, as participants were more likely to altruistically punish violators of social contracts than other scenarios (Experiments 1 and 2), and also incur more costs to behave altruistically towards others when feeling empathic than different emotional states (Experiment 3). These results provide clear support for the use and value of this novel task in future research

Solution of the two identical ion Penning trap final state

We have derived a closed form analytic expression for the asymptotic motion of a pair of identical ions in a high precision Penning trap. The analytic solution includes the effects of special relativity and the Coulomb interaction between the ions. The existence and physical relevance of such a final state is supported by a confluence of theoretical, experimental and numerical evidence.Comment: 5 pages and 2 figure

Formation of Kuiper-belt binaries through multiple chaotic scattering encounters with low-mass intruders

The discovery that many trans-neptunian objects exist in pairs, or binaries, is proving invaluable for shedding light on the formation, evolution and structure of the outer Solar system. Based on recent systematic searches it has been estimated that up to 10% of Kuiper-belt objects might be binaries. However, all examples discovered to-date are unusual, as compared to near-Earth and main-belt asteroid binaries, for their mass ratios of order unity and their large, eccentric orbits. In this article we propose a common dynamical origin for these compositional and orbital properties based on four-body simulations in the Hill approximation. Our calculations suggest that binaries are produced through the following chain of events: initially, long-lived quasi-bound binaries form by two bodies getting entangled in thin layers of dynamical chaos produced by solar tides within the Hill sphere. Next, energy transfer through gravitational scattering with a low-mass intruder nudges the binary into a nearby non-chaotic, stable zone of phase space. Finally, the binary hardens (loses energy) through a series of relatively gentle gravitational scattering encounters with further intruders. This produces binary orbits that are well fitted by Kepler ellipses. Dynamically, the overall process is strongly favored if the original quasi-bound binary contains comparable masses. We propose a simplified model of chaotic scattering to explain these results. Our findings suggest that the observed preference for roughly equal mass ratio binaries is probably a real effect; that is, it is not primarily due to an observational bias for widely separated, comparably bright objects. Nevertheless, we predict that a sizeable population of very unequal mass Kuiper-belt binaries is likely awaiting discovery.Comment: This is a preprint of an Article accepted for publication in Monthly Notices of the Royal Astronomical Society, (C) 2005 The Royal Astronomical Societ

Superscars in the LiNC=LiCN isomerization reaction

We demonstrate the existence of superscarring in the LiNC=LiCN isomerization reaction described by a realistic potential interaction in the range of readily attainable experimental energies. This phenomenon arises as the effect of two periodic orbits appearing "out of the blue"in a saddle--node bifurcation taking place in the dynamics of the system. Potential practical consequences of this superlocalization in the corresponding wave functions are also considered.Comment: 6 pages, 5 figures. to appear in EP

Shear stress fluctuations in the granular liquid and solid phases

We report on experimentally observed shear stress fluctuations in both granular solid and fluid states, showing that they are non-Gaussian at low shear rates, reflecting the predominance of correlated structures (force chains) in the solidlike phase, which also exhibit finite rigidity to shear. Peaks in the rigidity and the stress distribution's skewness indicate that a change to the force-bearing mechanism occurs at the transition to fluid behaviour, which, it is shown, can be predicted from the behaviour of the stress at lower shear rates. In the fluid state stress is Gaussian distributed, suggesting that the central limit theorem holds. The fibre bundle model with random load sharing effectively reproduces the stress distribution at the yield point and also exhibits the exponential stress distribution anticipated from extant work on stress propagation in granular materials.Comment: 11 pages, 3 figures, latex. Replacement adds journal reference and addresses referee comment

What can a participatory approach to research and evaluation contribute to the field of integrated care?

Better integration of care within the health sector and between health and social care is seen in many countries as an essential way of addressing the enduring problems of dwindling resources, changing demographics and unacceptable variation in quality of care. Current research evidence about the effectiveness of integration efforts supports neither the enthusiasm of those promoting and designing integrated care programmes nor the growing efforts of practitioners attempting to integrate care on the ground. In this paper we present a methodological approach, based on the principles of participatory research, that attempts to address this challenge. Participatory approaches are characterised by a desire to use social science methods to solve practical problems and a commitment on the part of researchers to substantive and sustained collaboration with relevant stakeholders. We describe how we applied an emerging practical model of participatory research, the researcher-in-residence model, to evaluate a large-scale integrated care programme in the UK. We propose that the approach added value to the programme in a number of ways: by engaging stakeholders in using established evidence and with the benefits of rigorously evaluating their work, by providing insights for local stakeholders that they were either not familiar with or had not fully considered in relation to the development and implementation of the programme and by challenging established mindsets and norms. While there is still much to learn about the benefits and challenges of applying participatory approaches in the health sector, we demonstrate how using such approaches have the potential to help practitioners integrate care more effectively in their daily practice and help progress the academic study of integrated care