9,827 research outputs found
Mission 73 - Summary and data catalog
Earth resources program geographic applications program summary, recommendations, and data catalog for remote sensor mission 7
Energy-balance climate models
An introductory survey of the global energy balance climate models is presented with an emphasis on analytical results. A sequence of increasingly complicated models involving ice cap and radiative feedback processes are solved and the solutions and parameter sensitivities are studied. The model parameterizations are examined critically in light of many current uncertainties. A simple seasonal model is used to study the effects of changes in orbital elements on the temperature field. A linear stability theorem and a complete nonlinear stability analysis for the models are developed. Analytical solutions are also obtained for the linearized models driven by stochastic forcing elements. In this context the relation between natural fluctuation statistics and climate sensitivity is stressed
Geographic analysis of multiple sensor data from the NASA/USGS earth resources program
Qualitative and quantitative analyses were made of multi-sensor data acquired during aircraft missions. While the principal analysis effort was concentrated on imagery taken over test sites in Southern California, data were also studied from records acquired on missions over test sites at Phoenix, Chicago, Asheville, and New Orleans. The objectives of the analyses were: (1) to determine the capabilities of ten remote sensors in identifying the elements of information necessary in conducting geographic investigations in land use analysis, urban problems, surface energy budget, and soil moisture; (2) to determine the feasibility of using these sensors for these purposes at orbital altitudes; and (3) to collate and analyze ground and air data previously collected and assemble it in a format useful in the accomplishment of cost effectiveness studies
Empirical constraints on vacuum decay in the stringy landscape
It is generally considered as self evident that the lifetime of our vacuum in
the landscape of string theory cannot be much shorter than the current age of
the universe. Here I show why this lower limit is invalid. A certain type of
``parallel universes'' is a necessary consequence of the string-landscape
dynamics and might well allow us to ``survive'' vacuum decay. As a consequence
our stringy vacuum's lifetime is empirically unconstrained and could be very
short. Based on this counter-intuitive insight I propose a novel type of
laboratory experiment that searches for an apparent violation of the
quantum-mechanical Born rule by gravitational effects on vacuum decay. If the
lifetime of our vacuum should turn out to be shorter than 6 x 10^{-13} seconds
such an experiment is sufficiently sensitive to determine its value with
state-of-the-art equipment.Comment: 13 pages, 2 figures, proposes a laboratory experimen
The Angular Diameter and Fundamental Parameters of Sirius A
The Sydney University Stellar Interferometer (SUSI) has been used to make a
new determination of the angular diameter of Sirius A. The observations were
made at an effective wavelength of 694.1 nm and the new value for the
limb-darkened angular diameter is 6.048 +/- 0.040mas (+/-0.66%). This new
result is compared with previous measurements and is found to be in excellent
agreement with a conventionally calibrated measurement made with the European
Southern Observatory's Very Large Telescope Interferometer (VLTI) at 2.176
microns (but not with a second globally calibrated VLTI measurement). A
weighted mean of the SUSI and first VLTI results gives the limb-darkened
angular diameter of Sirius A as 6.041 +/- 0.017mas (+/-0.28%). Combination with
the Hipparcos parallax gives the radius equal to 1.713 +/- 0.009R_sun. The
bolometric flux has been determined from published photometry and
spectrophotometry and, combined with the angular diameter, yields the emergent
flux at the stellar surface equal to (5.32+/- 0.14)x10^8 Wm^-2 and the
effective temperature equal to 9845 +/- 64 K. The luminosity is 24.7 +/- 0.7
L_sun.Comment: Accepted for publication in PAS
Access to bank finance for Scottish SMEs.
There is evidence that some SMEs may still face difficulties in accessing bank finance from lenders (CEEDR, 2007). This paper reports an in-depth study into demand and supply side issues relating to access to bank finance by Scottish SMEs and whether there is still market
failure associated with good, bankable business cases from SMEs that do not receive finance. We argue that our study utilises innovative methodology and is relatively rare as a robust study in this area. We combine demand side in depth survey analysis of SMEs with supply side
analysis by bank managers of real business propositions through verbal protocol analysis.
This paper discusses the ability of SMEs to access debt finance from the commercial banks in Scotland, it reports findings from a survey of 51 SMEs that had reported having difficulty raising finance and from interviews with bank managers utilising verbal protocol analysis with validated
real SME business proposals to give insights into the decision-making of bank managers in the processing of proposals from SMEs. Theoretically, there are categories of SMEs that may face greater difficulties or contain circumstances in which it is more difficult for bank managers to apply standard decision-making models and these categories are explored to provide a
theoretical framework for the investigation. The theoretical framework provides themes for discussion of the findings. These include for example; younger SMEs and owners, rural-based SMEs and manufacturing SMEs. Bank officers were found to follow standard financial models,
although considerable discretion could be exercised by senior bank managers often leading to a heavy reliance on personal relationships. Smaller and newer SMEs where discretion was more limited were more likely to face difficulties. The study revealed a number of categories of SMEs that face difficulties, including strong growth SMEs in rural environments, new and young SMES,young entrepreneurs seeking start-up finance and manufacturing SMEs seeking to diversify and finance new product development. Focusing on these categories of SMEs,we analyse survey evidence, in depth case studies and
verbal protocol analysis with bank managers to discuss research questions on whether informational effects can lead to market failure in the provision of debt finance, the circumstances in which sound propositions are turned down and whether such circumstances can be prevented. This forms the basis for development of conclusions on the continued existence of a debt gap for certain categories of SMEs and some policy implications
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