575 resultados para scatter hoarding
Resumo:
China has experienced considerable economic growth since 1978, which was accompanied by unprecedented growth in urbanization and, more recently, by associated rising urban housing and land banking issues. One such issue is that of land hoarding - where real estate developers purchase land to hold unused in the rising market for a future lucrative sale, often several years later. This practice is outlawed in China, where land use is controlled by increasingly strengthened Government policies and inspectors. Despite this, land hoarding continues apace, with the main culprits being the developers and inspectors working subversively. This resembles a game between two players - the inspector and the developer - which provides the setting for this paper in developing an evolutionary game theory model to provide insights into dealing with the dilemmas faced by the players. The logic and dilemma of land banking strategy and illegal land banking issues are analysed, along with the land inspector’s role from a game theory perspective by determining the replication dynamic mechanism and evolutionary stable strategies under the various conditions that the players face. The major factors influencing the actions of land inspectors, on the other hand, are the costs of inspection, no matter if it is strict or indolent, conflict costs, and income and penalties from corruption. From this, it is shown that, when the net loss for corruption (income from corruption minus the penalties for corruption and cost of strict inspections) is less than the cost of strict inspections, the final evolutionary stable strategy of the inspectors is to carry out indolent inspections. Then, whether penalising developers for hoarding is severe or not, the evolutionary strategy for the developer is to hoard. The implications for land use control mechanisms and associated developer-inspector actions and counteractions are then examined in the light of the model's properties.
Resumo:
Scatter/Gather systems are increasingly becoming useful in browsing document corpora. Usability of the present-day systems are restricted to monolingual corpora, and their methods for clustering and labeling do not easily extend to the multilingual setting, especially in the absence of dictionaries/machine translation. In this paper, we study the cluster labeling problem for multilingual corpora in the absence of machine translation, but using comparable corpora. Using a variational approach, we show that multilingual topic models can effectively handle the cluster labeling problem, which in turn allows us to design a novel Scatter/Gather system ShoBha. Experimental results on three datasets, namely the Canadian Hansards corpus, the entire overlapping Wikipedia of English, Hindi and Bengali articles, and a trilingual news corpus containing 41,000 articles, confirm the utility of the proposed system.
Resumo:
The goal of this study was to characterize the image quality of our dedicated, quasi-monochromatic spectrum, cone beam breast imaging system under scatter corrected and non-scatter corrected conditions for a variety of breast compositions. CT projections were acquired of a breast phantom containing two concentric sets of acrylic spheres that varied in size (1-8mm) based on their polar position. The breast phantom was filled with 3 different concentrations of methanol and water, simulating a range of breast densities (0.79-1.0g/cc); acrylic yarn was sometimes included to simulate connective tissue of a breast. For each phantom condition, 2D scatter was measured for all projection angles. Scatter-corrected and uncorrected projections were then reconstructed with an iterative ordered subsets convex algorithm. Reconstructed image quality was characterized using SNR and contrast analysis, and followed by a human observer detection task for the spheres in the different concentric rings. Results show that scatter correction effectively reduces the cupping artifact and improves image contrast and SNR. Results from the observer study indicate that there was no statistical difference in the number or sizes of lesions observed in the scatter versus non-scatter corrected images for all densities. Nonetheless, applying scatter correction for differing breast conditions improves overall image quality.
Resumo:
We have obtained density and temperature informations on an expanding KrF laser-ablated magnesium plume via optical Thomson scatter with a frequency doubled Nd:YAG laser. The electron temperature was found to decay with the expected Te t-1 dependence. However, we have found the electron density to have a time dependence ne t-4.95 which can be explained by strong recombination processes. We also observed atomic Raman satellites originating from transitions between the different angular momentum levels of the metastable 3P0 term in Mg I.
Resumo:
In this paper we describe experimental results on angularly resolved x-ray scatter from a sample of warm dense aluminium that has been created by double sided laser-driven shock compression. The experiment was carried out on the Central Laser Facility of the Rutherford Appleton Laboratory, using the VULCAN laser. The form of the angularly resolved scatter cross-section was compared with predictions based on a series of molecular dynamics simulations with an embedded atom potential, a Yukakwa potential and a bare Coulomb potential. The importance of screening is evident from the comparison and the embedded atom model seems to match experiment better than the Yukawa potential.
Resumo:
We have carried out an optical Thomson scatter study of a KrF laser-ablated Mg plume. The evolution of the electron temperature and density at distances 2-5 mm from the target surface has been studied. We have observed that the electron density falls more rapidly than the atomic density and believe that this is a result of rapid dielectronic recombination. A comparison of the electron density profile and evolution with simple hydrodynamic modeling indicates that there is a strong absorption of the laser in the plasma vapor above the target, probably due to photoionization. We also conclude that an isothermal model of expansion better fits the data than an isentropic expansion model. Finally, we compared data obtained from Thomson scatter with those obtained by emission spectroscopy under similar conditions. The two sets of data have differences but are broadly consistent.