Fresnel concentrating collector

An advanced point focusing solar technology demonstrated potential for near term commercialization as a renewable energy technology. The design features combine to produce a highly efficient, low cost, safe, adaptable, durable system which is simple to manufacture, install and maintain

Analytical and experimental evaluation of techniques for the fabrication of thermoplastic hologram storage devices

The results of an experimental investigation on recording information on thermoplastic are given. A description was given of a typical fabrication configuration, the recording sequence, and the samples which were examined. There are basically three configurations which can be used for the recording of information on thermoplastic. The most popular technique uses corona which furnishes free charge. The necessary energy for deformation is derived from a charge layer atop the thermoplastic. The other two techniques simply use a dc potential in place of the corona for deformation energy

Experimental investigations of solid nitrogen formed by cryopumping

Density, thermoconductivity, and sticking coefficient of nitrogen condensate formed on cryopum

Critical problems of computational aeroacoustics

The aeroacoustics of rigid boundaries is discussed. Lighthill gave a formulation of this problem in which he showed that the sources of the acoustic field were quadrupole in nature. We have preferred a different formulation of the problem, in which the quadrupoles are sources for a nonlinear wave equation, as opposed to the linear one used by Lighthill. This is given here in a figure which also gives further details of a solution procedure for the Euler equations appropriate for the aeroelastic problem and motivated by the analysis of Crow. In accordance with our formulation, we contend that an algorithm for accurate solutions of an inhomogeneous nonlinear wave equation is of prime importance

The Economics of Small Worlds

We examine a simple economic model of network formation where agents benefit from indirect relationships. We show that small-world features—short path lengths between nodes together with highly clustered link structures—necessarily emerge for a wide set of parameters

A study on task difficulty and acceleration stress

The results of two experiments which relate to task difficulty and the effects of environmental stress on tracking performance are discussed and compared to subjective evaluations. The first experiment involved five different sum of sine tracking tasks which humans tracked both in a static condition and under a 5 Gz acceleration stress condition. The second experiment involved similar environmental stress conditions but in this case the tasks were constructed from deterministic functions with specially designed velocity and acceleration profiles. Phase Plane performance analysis was conducted to study potential measures of workload or tracking difficulty

Measuring Organizational Performance in Strategic Human Resource Management: Looking Beyond the Lamppost

A major challenge for Strategic Human Resource Management research in the next decade will be to establish a clear, coherent and consistent construct for organizational performance. This paper describes the variety of measures used in current empirical research linking human resource management and organizational performance. Implications for future research are discussed amidst the challenges of construct definition, divergent stakeholder criteria and the temporal dynamics of performance. A model for performance information markets to address these challenges is introduced. The model uses a multi-dimensional weighted performance measurement system and a free information flow exchange mechanism for determining performance achievement criteria

Scintillation detector for carbon-14

Detector consists of plastic, cylindrical double-wall scintillation cell, which is filled with gas to be analyzed. Thin, inner cell wall is isolated optically from outer (guard) scintillator wall by evaporated-aluminum coating. Bonding technique provides mechanical support to cell wall when device is exposed to high temperatures

Measuring Organizational Performance in Strategic Human Resource Management: Problems and Prospects

A major challenge for Strategic Human Resource Management research in the next decade will be to establish a clear, coherent and consistent construct for organizational performance. This paper describes the variety of measures used in current empirical research linking human resource management and organizational performance. Implications for future research are discussed amidst the challenges of construct definition, divergent stakeholder criteria and the temporal dynamics of performance. The concept of performance information markets that addresses these challenges is proposed as a framework for the application of multi-dimensional weighted performance measurement systems