839 research outputs found
Reviews
Reviews of Trade Unionism Under Collective Bargaining: A Theory Based on Comparisons of Six Countries, Union Growth and the Business Cycle, Industrial Relations: A Textboo
Impasse Procedures: The American Experience
Recent American industrial relations have been characterized by experimentation with alternatives to the strike. Much of this experimentation is the result of public sector workers gaining access to collective bargaining while continuing to be denied access to the strike. In the United States, as in many countries, governments have taken the view that their employees should not strike. Considerations of public service, sovereignty and representative democracy, essentiality of government services and of the lack of some private sector restramts underlie this vie
A Quantitative Comparison of Opacities Calculated Using the Distorted- Wave and -Matrix Methods
The present debate on the reliability of astrophysical opacities has reached
a new climax with the recent measurements of Fe opacities on the Z-machine at
the Sandia National Laboratory \citep{Bailey2015}. To understand the
differences between theoretical results, on the one hand, and experiments on
the other, as well as the differences among the various theoretical results,
detailed comparisons are needed. Many ingredients are involved in the
calculation of opacities; deconstructing the whole process and comparing the
differences at each step are necessary to quantify their importance and impact
on the final results. We present here such a comparison using the two main
approaches to calculate the required atomic data, the -Matrix and
distorted-wave methods, as well as sets of configurations and coupling schemes
to quantify the effects on the opacities for the and ions.Comment: 10 pages, 2 figure
Direct measurement of strontium 90 in groundwater: geometry optimisation of a photodiode based detector
This paper examines the feasibility of detecting strontium 90 in groundwater directly with photodiodes and considers the physical parameters which maximise radiation absorption within the detector. Geant4 simulations were used to draw comparisons between silicon, gallium arsenide and cadmium telluride detectors of varying surface area and thickness. Detectors were compared in their ability to absorb point and scattered sources of radiation. The results indicate that a detector, of 10 mm2 surface area, and 1 mm thickness offered the highest detection efficiency in a contaminated groundwater simulation. 1 mm thick and 100 mm2 detectors cadmium telluride and gallium arsenide detectors were modelled in a groundwater borehole scenario. Each material offered similar detection efficiency, but the greater backscattering effect in cadmium telluride resulted in a greater peak at lower energies compared to that observed in gallium arsenide
On variational principles for coherent vortex structures
Different approaches are discussed of variational principles characterizing coherent vortex structures in two-dimensional flows. Turbulent flows seem to form ordered structures in the large scales of the motion and the self-organization principle predicts asymptotic states realizing an extremal value of the energy or a minimum of enstrophy. On the other hand the small scales take care of the increase of entropy, and asymptotic results can be obtained by applying the theory of equilibrium statistical mechanics
Statistics of an Unstable Barotropic Jet from a Cumulant Expansion
Low-order equal-time statistics of a barotropic flow on a rotating sphere are
investigated. The flow is driven by linear relaxation toward an unstable zonal
jet. For relatively short relaxation times, the flow is dominated by
critical-layer waves. For sufficiently long relaxation times, the flow is
turbulent. Statistics obtained from a second-order cumulant expansion are
compared to those accumulated in direct numerical simulations, revealing the
strengths and limitations of the expansion for different relaxation times.Comment: 23 pages, 8 figures. Version to appear in J. Atmos. Sc
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