10,714 research outputs found
Manually operated elastomer heat pump
Device consisting of a rotating mechanism, a frame with multiple wide bands of rubber, and a fluid bath, demonstrates the feasibility of a human operated device capable of cooling or producing heat. This invention utilizes the basic thermodynamic properties of natural rubber
Initial post-buckling behavior of toroidal shell segments
Initial post-buckling behavior of toroidal shell segment
Buckling of imperfect cylindrical shells under axial compression and external pressure
Axisymmetric deformation effects on cylindrical shell buckling under axial compressio
Quality-weld parameters for microwelding techniques and equipment
Limited-amplitude, controlled-decay process improves the reliability of microwelding. The system consists in building a capacitor-discharge welder for control of the shape of the weld pulse. Standard welders may be modified
Dynamic buckling estimates
Dynamic buckling estimates for sensitive structures subjected to finite-time loadin
Using choice experiments to explore the spatial distribution of willingness to pay for rural landscape improvements
We report findings from a choice experiment survey designed to estimate the economic benefits from policy measures which improve the rural landscape under an agri-environment scheme in the Republic of Ireland. Using a panel mixed logit specification to account for unobserved taste heterogeneity we derive individual- specific willingness to pay estimates for each respondent in the sample. We subsequently investigate the existence of spatial dependence of these estimates. Results suggest the existence of positive spatial autocorrelation for all rural landscape attributes. As a means of benefit transfer, kriging methods are employed to interpolate willingness to pay estimates across the whole of the Republic of Ireland. The kriged WTP surfaces confirm the existence of spatial dependence and illustrate the implied spatial variation and regional disparities in WTP for all the rural landscape improvements
Phase Transitions in Ultra-Cold Two-Dimensional Bose Gases
We briefly review the theory of Bose-Einstein condensation in the
two-dimensional trapped Bose gas and, in particular the relationship to the
theory of the homogeneous two-dimensional gas and the
Berezinskii-Kosterlitz-Thouless phase. We obtain a phase diagram for the
trapped two-dimensional gas, finding a critical temperature above which the
free energy of a state with a pair of vortices of opposite circulation is lower
than that for a vortex-free Bose-Einstein condensed ground state. We identify
three distinct phases which are, in order of increasing temperature, a phase
coherent Bose-Einstein condensate, a vortex pair plasma with fluctuating
condensate phase and a thermal Bose gas. The thermal activation of
vortex-antivortex pair formation is confirmed using finite-temperature
classical field simulations
Testing the stability of the benefit transfer function for discrete choice contingent valuation data
We examine the stability of the benefit transfer function across 42 recreational forests in the British Isles. A working definition of reliable function transfer is put forward, and a suitable statistical test is provided. The test is based on the sensitivity of the model log-likelihood to removal of individual forest recreation sites. We apply the proposed methodology on discrete choice contingent valuation data and find that a stable function improves our measure of transfer reliability, but not by much. We conclude that, in empirical studies on transferability, function stability considerations are secondary to the availability and quality of site attribute data. Modellers’ can study the advantages of transfer function stability vis-à-vis the value of additional information on recreation site attributes
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