5,464 research outputs found
The timing and magnitude of upper body muscular activity during a field hockey hit
The aim of this study was to investigate the contributions to stick motion in the field hockey hit by monitoring muscle activity in the arms and trunk and synchronising these with arm and stick kinematics. The hits of ten male, university-level field hockey players were analysed. Whilst their interpretation is complicated by the closed kinetic loop formed by the arms and stick, the data collected here represent a step forward in establishing the contributions from muscular activity
and segmental interactions to the field hockey hit. This study has shown that EMG analysis alone is not sufficient to explain the nature of muscular activity patterns and that the temporal aspects of EMG need to be examined in combination with kinematic data to ascertain the role of muscular activity during movement
A climatically-derived global soil moisture data set for use in the GLAS atmospheric circulation model seasonal cycle experiment
Algorithms for point interpolation and contouring on the surface of the sphere and in Cartesian two-space are developed from Shepard's (1968) well-known, local search method. These mapping procedures then are used to investigate the errors which appear on small-scale climate maps as a result of the all-too-common practice of of interpolating, from irregularly spaced data points to the nodes of a regular lattice, and contouring Cartesian two-space. Using mean annual air temperatures field over the western half of the northern hemisphere is estimated both on the sphere, assumed to be correct, and in Cartesian two-space. When the spherically- and Cartesian-approximted air temperature fields are mapped and compared, the magnitudes (as large as 5 C to 10 C) and distribution of the errors associated with the latter approach become apparent
On the design of an interactive biosphere for the GLAS general circulation model
Improving the realism and accuracy of the GLAS general circulation model (by adding an interactive biosphere that will simulate the transfers of latent and sensible heat from land surface to atmosphere as functions of the atmospheric conditions and the morphology and physiology of the vegetation) is proposed
Forced double Kelvin waves in a stratified ocean
This paper examines the linear response of a two-layer uniformly rotating ocean of infinite horizontal extent with a discontinuity in depth to a divergence-free transient wind stress. Initially the ocean is at rest and the wind stress is directed perpendicular to the escarpment. A rigid lid is employed to filter out the external double Kelvin wave and an analytic solution is derived, using transform techniques, for the forced internal double Kelvin wave which is trapped along the depth discontinuity. Parameter values are chosen which most accurately model the Mendocino escarpment oriented almost zonally off the northern California coast. Soon after the wind stress is applied a single large wave is generated in the neighborhood of the wind stress curl origin. The wave has a maximum amplitude of 3 m, a phase speed of approximately 2.2 km day–1 and a wavelength in the order of 200 km. Furthermore the forced double Kelvin wave is found to exhibit a 6 day oscillation which is independent of the e-folding time scale of the wind stress. At any fixed location along the escarpment the solution also displays amplitude modulation. An investigation of how sensitive the solutions are to the upper layer depth and stratification is presented. A brief discussion of the response produced by a time-periodic spatially independent wind stress directed parallel to the escarpment and suddenly applied to a quiescent ocean, is also presented. It is suggested that double Kelvin waves may perhaps be detected from deep-sea buoy measurements
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Performativity and convergence in comparative corporate governance
We engage with the convergence/divergence debate in the comparative study of corporate governance by commending a nuanced formulation of the convergence thesis. Directing attention to the precarious constitution and adoption of knowledge claims about corporate status and architecture in the field of corporate governance we suggest that the study of comparative corporate governance might usefully incorporate consideration of claims about corporate governance as potentially performative statements that function to stabilize particular ideas of status and architecture of the modern corporation with substantive outcomes for political economy, thereby influencing the shape of the institutions comprising the field of corporate governance. We conclude that the predominantly epistemological preoccupations of participants in the convergence/divergence debate could be usefully refined and supplemented by giving closer attention, empirical as well as theoretical, to the relation between performativity, convergence/divergence, and political economy
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The Rise of the 1%: An Organizational Explanation
The paper adopts an organizational perspective to explore the conditions of possibility of the recent re-emergence of overt class-based discourse on one hand, epitomized by the ‘We are the 99%’ movement, and the rise on the other hand of a populist, nativist and sometimes overtly fascist right. It is argued that these phenomena, reflecting the increasingly crisis-pronecharacter of global capitalism, the growing gap between rich and poor and a generalized sense of insecurity, are rooted in the dismantling of socially embedded organizations through processes often described as‘financialization’, driven by the taken-for-granted dominance of neoliberal ideology. The paper explores the rise to dominance of the neoliberal ‘thought style’ and its inherent logic in underpinning the dismantling and restructuring of capitalist organization. Its focus is upon transnational value chain capitalism which has rebalanced power relations in favour of a small elite who is able to operate and realize wealth in ways that defy and often succeed in escaping the regulation of nation states
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Social ontology and the modern corporation
In an assessment of Lawson’s social ontological analysis of the modern corporation, we consider what is marginalized: the significance of the status and the effects of the separate legal entity (SLE). The SLE is conceived as a specific type of construct that is ascribed particular properties through its stabilization within and between different (legal and economic) discourses. By showing how the SLE, as a reified construct, is rendered meaningful, real and/or consequential, we illustrate how the ‘social ontology’ of the modern corporation is radically contingent and inescapably contested. Given that the social ontology of the corporation defies definitive specification, we regard the prospect of the completeness of its disclosure (e.g. by foregrounding a specific referent) as problematic. Indeed, any account of social ontology that foregrounds a specific referent is seen to obscure a political process in which the stabilization of the SLE rests on the contingent foregrounding of particular priorities. This leads us to reflect on the power-inflected social organization of knowledge generation. Key to the explication of social ontology, and with specific reference to the corporation, is not, as Lawson contends, the concept of ‘community’ but the inescapability of contestation within relations of power that translate ontological openness into specific but precarious forms of ontic closure
THE PLANARITY OF THE STICK AND ARM MOTION IN THE FIELD HOCKEY HIT
The development of relevant simulation models is one way in which our knowledge of the field hockey hit may be improved. The aim of this study was to test the appropriateness of a planar pendulum model for the motion of the stick and arms during the downswing. The hits of 13 experienced female players were filmed, and swing planes were fitted to the motion of the stickface during the downswing. Low variability in the length of a segment’s projection onto the swing plane was taken as evidence for the validity of a planar model. Coefficients of variation of less than 5% for the stick and forearm lengths supported the use of such a model for these segments, but its validity for the upper arms is less certain
Analyzing the discharge regime of a large tropical river through remote sensing, ground-based climatic data, and modeling
This study demonstrates the potential for applying passive microwave satellite sensor data to infer the discharge dynamics of large river systems using the main stem Amazon as a test case. The methodology combines (1) interpolated ground-based meteorological station data, (2) horizontally and vertically polarized temperature differences (HVPTD) from the 37-GHz scanning multichannel microwave radiometer (SMMR) aboard the Nimbus 7 satellite, and (3) a calibrated water balance/water transport model (WBM/WTM). Monthly HVPTD values at 0.25° (latitude by longitude) resolution were resampled spatially and temporally to produce an enhanced HVPTD time series at 0.5° resolution for the period May 1979 through February 1985. Enhanced HVPTD values were regressed against monthly discharge derived from the WBM/WTM for each of 40 grid cells along the main stem over a calibration period from May 1979 to February 1983 to provide a spatially contiguous estimate of time-varying discharge. HVPTD-estimated flows generated for a validation period from March 1983 to February 1985 were found to be in good agreement with both observed arid modeled discharges over a 1400-km section of the main stem Amazon. This span of river is bounded downstream by a region of tidal influence and upstream by low sensor response associated with dense forest canopy. Both the WBM/WTM and HVPTD-derived flow rates reflect the significant impact of the 1982–1983 El Niño-;Southern Oscillation (ENSO) event on water balances within the drainage basin
Steady, barotropic wind and boundary-driven circulation on a polar plane
Steady, linear, barotropic wind and boundary forced circulation solutions in the presence of linear bottom friction are analytically derived in a circular basin of uniform depth on a polar tangent plane in which only first order effects of the Earth’s curvature are retained. Approximate solutions are constructed by using the well known method of aggregating the interior inviscid Sverdrup balance solution and the frictional wall boundary layer solution. In contrast to the width of mid-latitude frictional western boundary layers that scale as , the width of the polar frictional boundary layer adjacent to the basin wall is wider, scaling as , where is the bottom friction coefficient, is the coriolis parameter. Solutions are presented for a variety of wind stress curl distributions and for a prescribed inflow/outflow representative of the exchange of water masses between the Arctic and Atlantic basins. Boundary forced solutions are also derived in a basin with a uniform width step shelf. For this basin geometry the flow is mainly confined to the shelf, although a parameter regime is identified that supports significant flow in the deep basin
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