25,641 research outputs found
Inefficiency
We introduce an ordinal model of efficiency measurement. Our primitive is a notion of efficiency that is comparative, but not cardinal or absolute. In this framework, we postulate axioms that we believe an ordinal efficiency measure should satisfy. Primary among these are choice consistency and planning consistency, which guide the measurement of efficiency in a firm with access to multiple technologies. Other axioms include symmetry, which states that the names of commodities do not matter, scale-invariance, which says that units of measurement of commodities does not matter, and strong monotonicity, which states that efficiency should decrease if the inputs and outputs remain static when the technology becomes unambiguously more efficient. These axioms characterize a unique ordinal efficiency measure which is represented by the coefficient of resource utilization. By replacing symmetry (the weakest of our axioms) with a very mild continuity condition, we obtain a family of path-based measures.Efficiency Measurement, Coefficient of Resource Utilization, Ordinal, Choice Consistency, Planning Consistency, Path-based
Computation of turbulent boundary layers on curved surfaces, 1 June 1975 - 31 January 1976
An accurate method was developed for predicting effects of streamline curvature and coordinate system rotation on turbulent boundary layers. A new two-equation model of turbulence was developed which serves as the basis of the study. In developing the new model, physical reasoning is combined with singular perturbation methods to develop a rational, physically-based set of equations which are, on the one hand, as accurate as mixing-length theory for equilibrium boundary layers and, on the other hand, suitable for computing effects of curvature and rotation. The equations are solved numerically for several boundary layer flows over plane and curved surfaces. For incompressible boundary layers, results of the computations are generally within 10% of corresponding experimental data. Somewhat larger discrepancies are noted for compressible applications
Apollo spacecraft systems analysis program. A comparison of the computed LR received signal spectrum and the 1967 PEARL data
Similarities between experimentally measured power spectral density curves of landing radar signal returned from rough surface and computer simulated curves for sinusoidal surface
Progress in strain monitoring of tapestries
This paper reports interdisciplinary
research between conservators and
engineers designed to enhance the
long-term conservation of tapestries
(tapestry-weave hangings) on longterm
display. The aim is to monitor,
measure and document the strain
experienced by different areas of a
tapestry while it is hanging on display.
Initial research has established that
damage can be identified in the early
stages of its inception, i.e., before it is
visible to the naked eye. The paper also
reports initial results of strain data
visualisation that allows curators and
conservators to examine how strain
develops, thereby facilitating
predictions about the changes in the
form or condition of the tapestry.
Strain data visualisation also allows the
strain process to be recorded, thereby
facilitating the effective documentation
of display methods and conservation
interventions. The paper reports the
use of point measurements (using
silica optical fibre sensors) and full-field
monitoring (using 3-D
photogrammetry with digital image
correlation (DIC))
TQM in a test environment
In response to the changing aerospace economic climate, Martin Marietta Astronautics Group (MMAG) has adopted a Total Quality Management (TQM) philosophy to maintain a competitive edge. TQM emphasizes continuous improvement of processes, motivation to improve from within, cross-functional involvement, people empowerment, customer satisfaction, and modern process control techniques. The four major initiatives of TQM are Product Excellence, Manufacturing Resource Planning (MRP II), People Empowerment, and Subcontract Management. The Defense Space and Communications (DS&C) Test Lab's definition and implementation of the MRP II and people empowerment initiatives within TQM are discussed. The application of MRP II to environmental test planning and operations processes required a new and innovative approach. In an 18 month span, the test labs implemented MRP II and people empowerment and achieved a Class 'A' operational status. This resulted in numerous benefits, both tangible and intangible, including significant cost savings and improved quality of life. A detailed description of the implementation process and results are addressed
Long term condition monitoring of tapestries using image correlation
Digital Image Correlation (DIC) is used to extract non-contact full-field three-dimensional displacement and in-plane strains from an historic tapestries. A DIC-based approach is devised that allows the effect of RH variations on a tapestry to be quantified. A historical tapestry has been monitored in a closely controlled environment and in the natural environment. The results revealed that very small variations in RH can have significant effects on strain. An automated long term monitoring approach has been devised to allow strain data to be extracted in real time from tapestries in remote locations. The results show that DIC provides better understanding of the effect of RH fluctuations on strain which will ultimately lead to more insight into the degradation process of historical tapestries. The paper demonstrates the potential for using DIC as a condition monitoring tool
Brain matters…in social sciences
Here we offer a general introduction to cognitive neuroscience and provide examples relevant to psychology, healthcare and bioethics, law and criminology, information studies, of how brain studies have influenced, are influencing or show the potential to influence the social sciences. We argue that social scientists should read, and be enabled to understand, primary sources of evidence in cognitive neuroscience. We encourage cognitive neuroscientists to reflect upon the resonance that their work may have across the social sciences and to facilitate a mutually enriching interdisciplinary dialogue
CURRENT ISSUES AFFECTING TRADE AND TRADE POLICY: AN ANNOTATED LITERATURE REVIEW
This review provides a base of literature describing current issues and research on the impacts of lobalization and the industrialization of agriculture and recent approaches to analyze and model agricultural trade and trade policies. Three key factors of the survey are differentiated goods, global economic integration and international supply chain linkages. The review covers 182 publications, which are presented alphabetically by author with a brief annotation describing how it relates to the above criteria. The articles are also indexed by keyword. A brief summary highlights the documented literature and includes a series of issues for future discussion and research.International Relations/Trade,
- …
