As a Matter of Factions: The Budgetary Implications of Shifting Factional Control in Japan’s LDP

For 38 years, the Liberal Democratic Party (LDP) maintained single-party control over the Japanese government. This lack of partisan turnover in government has frustrated attempts to explain Japanese government policy changes using political variables. In this paper, we look for intraparty changes that may have led to changes in Japanese budgetary policy. Using a simple model of agenda-setting, we hypothesize that changes in which intraparty factions “control” the LDP affect the party’s decisions over spending priorities systematically. This runs contrary to the received wisdom in the voluminous literature on LDP factions, which asserts that factions, whatever their raison d’être, do not exhibit different policy preferences. We find that strong correlations do exist between which factions comprise the agenda-setting party “mainstream” and how the government allocates spending across pork-barrel and public goods items

Integrating out the Dirac sea: Effective field theory approach to exactly solvable four-fermion models

We use 1+1 dimensional large N Gross-Neveu models as a laboratory to derive microscopically effective Lagrangians for positive energy fermions only. When applied to baryons, the Euler-Lagrange equation for these effective theories assumes the form of a non-linear Dirac equation. Its solution reproduces the full semi-classical results including the Dirac sea to any desired accuracy. Dynamical effects from the Dirac sea are encoded in higher order derivative terms and multi-fermion interactions with perturbatively calculable, finite coefficients. Characteristic differences between models with discrete and continuous chiral symmetry are observed and clarified.Comment: 13 pages, 11 figures; v2: typos corrected (Eqs. 4 and 44

Rationality and the Foundations of Positive Political Theory

In this paper, we discuss and debunk the four most common critiques of the rational choice research program (which we prefer to call Positive Political Theory) by explaining and advocating its foundations: the rationality assumption, component analysis (abstraction), strategic behavior, and theory building, in turn. We argue that the rationality assumption and component analysis, properly understood, can be seen to underlie all social science, despite the protestations of critics. We then discuss the two ways that PPT most clearly contributes to political science (i.e., what distinguishes it from other research programs), namely the introduction of strategic behavior (people do not just act; they interact) and PPT’s more careful attention to the theory-building step within the scientific method. We explain the roles of theory- building and of empirical “testing,” respectively, in scientific inquiry, and the criteria by which theories should and should not be judged

A natural formation scenario for misaligned and short-period eccentric extrasolar planets

Recent discoveries of strongly misaligned transiting exoplanets pose a challenge to the established planet formation theory which assumes planetary systems to form and evolve in isolation. However, the fact that the majority of stars actually do form in star clusters raises the question how isolated forming planetary systems really are. Besides radiative and tidal forces the presence of dense gas aggregates in star-forming regions are potential sources for perturbations to protoplanetary discs or systems. Here we show that subsequent capture of gas from large extended accretion envelopes onto a passing star with a typical circumstellar disc can tilt the disc plane to retrograde orientation, naturally explaining the formation of strongly inclined planetary systems. Furthermore, the inner disc regions may become denser, and thus more prone to speedy coagulation and planet formation. Pre-existing planetary systems are compressed by gas inflows leading to a natural occurrence of close-in misaligned hot Jupiters and short-period eccentric planets. The likelihood of such events mainly depends on the gas content of the cluster and is thus expected to be highest in the youngest star clusters.Comment: 7 pages, 4 figures. Accepted for publication in MNRAS. Updated to match published versio

Are older people putting themselves at risk when using their walking frames?

Background Walking aids are issued to older adults to prevent falls, however, paradoxically their use has been identified as a risk factor for falling. To prevent falls, walking aids must be used in a stable manner, but it remains unknown to what extent associated clinical guidance is adhered to at home, and whether following guidance facilitates a stable walking pattern. It was the aim of this study to investigate adherence to guidance on walking frame use, and to quantify user stability whilst using walking frames. Additionally, we explored the views of users and healthcare professionals on walking aid use, and regarding the instrumented walking frames (‘Smart Walkers’) utilized in this study. Methods This observational study used Smart Walkers and pressure-sensing insoles to investigate usage patterns of 17 older people in their home environment; corresponding video captured contextual information. Additionally, stability when following, or not, clinical guidance was quantified for a subset of users during walking in an Activities of Daily Living Flat and in a gait laboratory. Two focus groups (users, healthcare professionals) shared their experiences with walking aids and provided feedback on the Smart Walkers. Results Incorrect use was observed for 16% of single support periods and for 29% of dual support periods, and was associated with environmental constraints and a specific frame design feature. Incorrect use was associated with reduced stability. Participants and healthcare professionals perceived the Smart Walker technology positively. Conclusions Clinical guidance cannot easily be adhered to and self-selected strategies reduce stability, hence are placing the user at risk. Current guidance needs to be improved to address environmental constraints whilst facilitating stable walking. The research is highly relevant considering the rising number of walking aid users, their increased falls-risk, and the costs of falls. Trial Registration Not applicable

A novel mooring tether for highly dynamic offshore applications; mitigating peak and fatigue loads via selectable axial stiffness (conference paper)

PublishedHighly dynamic floating bodies such as wave energy convertors (WECs) require mooring lines with particular mechanical properties; the mooring system must achieve adequate station keeping whilst controlling mooring tensions within acceptable limits. Currently, fibre ropes are commonly used but many mooring designers are seeking alternative solutions that can offer more favourable mechanical properties. The compliance offered by a mooring system will depend largely on the axial stiffness of the mooring lines. Whilst fibre ropes can offer lower axial stiffness than alternatives such as chain and wire rope, there remains a fundamental conflict which prohibits the free selection of axial stiffness properties. This conflict exists because the axial stiffness is strongly governed by the minimum breaking load (MBL) of the rope. The specified MBL must be sufficient to accommodate the predicted peak tension loads with an appropriate factor of safety (FOS) to cater for uncertainties and degradations. In achieving a sufficient MBL, the designer is often forced to accept a higher axial stiffness than is preferred. A potential benefit of reducing the axial stiffness of a mooring line is the reduction of peak loads and fatigue loads. This allows a reduction in mass of both the floating body and the mooring system, thus reducing costs and improving system reliability. This work describes the 'Exeter Tether', an innovation in mooring tether design which decouples the axial stiffness properties from the MBL of the tether. Removing this constraint allows a tether to be specified according to both MBL and axial stiffness. The principals behind the novel tether design are introduced along with an outline of 10 prototype tether variants manufactured in collaboration with Lankhorst Ropes. Results from the proof of concept tests at the University of Exeter's Dynamic Marine Component Test Facility (DMaC) are presented together with preliminary findings from sea trials at the South West Moorings Test Facility (SWMTF). The anticipated load mitigation introduced via the mooring tether is investigated and the implications for system design are discussed.UK Centre for Marine Energy Research (UKCMER) through the SuperGen programme funded by the EPSR

Offshore reliability approach for floating renewable energy devices

30th International Conference on Ocean, Offshore and Arctic Engineering, Rotterdam, The Netherlands, 19 – 24 June 2011The viability and success of Marine Renewable Energy installations is strongly dependent on the reliability of devices as this determines the amount of generated electricity and the cost for operation and maintenance. Reliability testing of critical components could mitigate these difficulties and provide device developers with a possibility to reveal early failures, gain information on lifetime criteria and provide project developers, investors and certification agencies with the required reliability demonstration and evidence of suitable risk control. The application of component reliability testing can reveal design weaknesses prior to deployment and establish necessary reliability and maintenance information. Components tested under service simulated conditions could be evaluated regarding performance, expected lifetime and subsequently be (cost-)optimised. Two test facilities that enable component reliability testing for marine renewable energy converters developed within the Peninsula Research Institute for Marine Renewable Energy (PRIMaRE) group at the University of Exeter are described. Those two facilities will allow measuring loads that are experienced in the field through prototype testing at the South Western Mooring Test Facility (SWMTF) and subsequently replicate those load conditions (or information from device developers) at the DMaC for accelerated reliability testing and design enhancement. The (SWMTF) is a unique mooring load and response test facility, at large scale in real sea condition and has been recently installed. The Dynamic Marine Component Test facility (DMaC) is capable to perform accelerated component testing under simulated in-service field conditions in four degree of freedom. This paper will describe the test facilities developed within the PRIMaRE group and discuss the approach of the group to mitigate risk for marine renewable energy installations. Furthermore load and response data from sea trial will be used to highlight the importance of this research activity.South West Regional Development Agency: PRIMaREEngineering and Physical Sciences Research Council (EPSRC) : SUPERGEN Marine Doctoral Programm

Control and Instrumentation Topologies for an Integrated Wave Energy Array

SubmittedControl and Instrumentation (C&I) systems provide the framework for monitoring critical data streams and implementing control functions during the operation of a wave energy converter. However, cost and power constraints of wave energy converters present a challenge in designing a C&I architecture that is appropriate for the application. This study describes the design of a C&I system for an integrated wave en-ergy array. A specification is first developed by defining operational requirements and design principles, measurement and control priorities are then identified, incorporating a failure mode and effects analysis. Available instrumentation options in the industry are reviewed and C&I topologies are presented. A distribut-ed control system is proposed for the Albatern WaveNET Array, allowing for the implementation of control and protection strategies and condition monitoring. Improved C&I allows for the reduction of unplanned maintenance, maximising device availability for energy production.The author would like to thank the industrial and academic supervisors, in addition to many industrial representatives whom provided valuable input to this paper. The support of the ETI and RCUK Energy Programme funding for IDCORE (EP/J500847/1) is gratefully acknowledged