41,420 research outputs found
Bounds for eigenvalue ratios of the Laplacian
For a bounded domain with a piecewise smooth boundary in an
-dimensional Euclidean space , we study eigenvalues of the
Dirichlet eigenvalue problem of the Laplacian. First we give a general
inequality for eigenvalues of the Laplacian. As an application, we study lower
order eigenvalues of the Laplacian and derive the ratios of lower order
eigenvalues of the Laplacian.Comment: 14 page
Experimental and theoretical research on the electrical conductivity of a liquid desiccant for the liquid desiccant air-conditioning system: LiCl aqueous solution
At present, the energy consumption in buildings occupies a large proportion of total energy use, and air-conditionings cost a large proportion of energy in the buildings. The liquid desiccant air-conditioning system has a good energy saving potential and the electrodialysis (ED) regeneration is a reliable choice for the liquid desiccant regeneration. In order to establish the energy consumption model and the performance coefficient model of liquid desiccant air-conditioning system based on ED regeneration using LiCl, experimental and theoretical research on the electrical conductivity of LiCl aqueous solution with a lot of concentrations and temperatures was conducted in this paper. The results show that when polynomial degrees of the mass concentration and the temperature of the LiCl aqueous solution are both 3, the electrical conductivity model for the LiCl aqueous solution is most suitable as its simplicity and high accuracy. Moreover, when the concentration is 36% and the temperature is 22 °C, the liquid desiccant cooling system has the maximum COP of about 5. Finally, a case study of a small office room was conducted, and the result shows that the liquid desiccant cooling system based on electrodialysis regeneration has a good energy-saving potential
Using fractals and power laws to predict the location of mineral deposits
Around the world the mineral exploration industry is interested in getting that small increase in probability measure on the earth's surface of where the next large undiscovered deposit might be found. In particular WMC Resources Ltd has operations world wide looking for just that edge in the detection of very large deposits of, for example, gold. Since the pioneering work of Mandelbrot, geologists have been familiar with the concept of fractals and self similarity over a few orders of magnitude for geological features. This includes the location and size of deposits within a particular mineral province. Fractal dimensions have been computed for such provinces and similarities of these aggregated measures between provinces have been noted. This paper explores the possibility of making use of known information to attempt the inverse process. That is, from lesser dimensional measures of a mineral province, for example, fractal dimension or more generally multi-fractal measures, is it possible to infer, even with small increase in probability, where the unknown (preferably large) deposits might be located
Caching and Auditing in the RPPM Model
Crampton and Sellwood recently introduced a variant of relationship-based
access control based on the concepts of relationships, paths and principal
matching, to which we will refer as the RPPM model. In this paper, we show that
the RPPM model can be extended to provide support for caching of authorization
decisions and enforcement of separation of duty policies. We show that these
extensions are natural and powerful. Indeed, caching provides far greater
advantages in RPPM than it does in most other access control models and we are
able to support a wide range of separation of duty policies.Comment: Accepted for publication at STM 2014 (without proofs, which are
included in this longer version
Possibly New Charmed Baryon States from Decay
We examine the invariant mass spectrum of in decay measured by BABAR and find that through the 2-step processes of
, where denotes a
charmed baryon state, some of the peaks can be identified with the established
, and . Moreover, in
order to account for the measured spectrum, it is necessary to introduce a new
charmed baryon resonance with MeV.Comment: 8 pages, 1 figure, title changed and discussions updated, version
accepted for publication in Phys. Rev.
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