Acoustical properties of double porosity granular materials

Granular materials have been conventionally used for acoustic treatment due to their sound absorptive and sound insulating properties. An emerging field is the study of the acoustical properties of multiscale porous materials. An example of these is a granular material in which the particles are porous. In this paper, analytical and hybrid analytical-numerical models describing the acoustical properties of these materials are introduced. Image processing techniques have been employed to estimate characteristic dimensions of the materials. The model predictions are compared with measurements on expanded perlite and activated carbon showing satisfactory agreement. It is concluded that a double porosity granular material exhibits greater low-frequency sound absorption at reduced weight compared to a solid-grain granular material with similar mesoscopic characteristics

STATE/REGIONAL ECONOMIC MODELS FOR LONG-RANGE ENERGY PLANNING

Community/Rural/Urban Development, Resource /Energy Economics and Policy,

THE EMPTYING OF THE COUNTRYSIDE AND ITS COST

Community/Rural/Urban Development,

MINNESOTA ENERGY-ECONOMIC INFORMATION SYSTEM

The energy-economic impact forecasting system presented here is a modular approach to both economic modeling and information systems development. A set of eleven modules--market, investment, demand, production, (input-output), employment, value added, labor force, population, household, fiscal, and ecologic--provides the data base and programming routines for simulating the state (or a substate regional) economy. An additional set of government function modules, including energy and environmental management, provides an auxiliary data base and forecasts for state and local government agencies. This series of data modules and related computer programs, locally called SIMLAB, is organized as a readily accessible regional impact simulation system.Community/Rural/Urban Development,

Exchange Narrowing Effects in the EPR Linewidth of Gd Diluted in Ce Compounds

Anomalous thermal behavior on the EPR linewidths of Gd impurities diluted in Ce compounds has been observed. In metals, the local magnetic moment EPR linewidth, \Delta H, is expected to increase linearly with the temperature. In contrast, in Ce_{x}La_{1-x}Os_{2} the Gd EPR spectra show a nonlinear increase. In this work, the mechanisms that are responsible for the thermal behavior of the EPR lines in Ce_{x}La_{1-x}Os_{2} are examined. We show that the exchange interaction between the local magnetic moments and the conduction electrons are responsible for the narrowing of the spectra at low temperatures. At high temperatures, the contribution to the linewidth of the exchange interaction between the local magnetic moments and the $Ce$ ions has an exponential dependence on the excitation energy of the intermediate valent ions. A complete fitting of the EPR spectra for powdered samples is obtained.Comment: 11 pages, 1 figur

A Characterization of concave mappings

This study focuses on Concave mappings, a class of univalent functions that exhibit a unique property: they map the unit disk onto a domain whose complement is convex. The main objective of this work is to characterize these mappings in terms of the real part of the expression $1 +zf''(z)/f'(z)$, considering scenarios where the omitted convex domain is either bounded or unbounded. In the case of a bounded convex domain, we investigate the pivotal role played by the Schwarzian derivative and the order of the functions in understanding the behavior and properties of these mappings

How to differentially detect potentially risky human papilloma virus strains in the human population?

The human papillomavirus (HPV) represents one of the most common sexually transmitted infections, knowing more than 100 viral types that, in relation to their oncological pathogenesis, are classified into types of high and low oncological risk. Cervical cancer is the second leading cause of death from malignant neoplasms in women. HPV can often cause warts. Most types of this virus are harmless, but a percentage of them are associated with an increased risk of cancer. These types are born from the genitals and are acquired through sexual contact with an engaged partner. Cervical cancer is the second leading cause of death from malignant neoplasms in women. HPV infection is responsible for various lesions in different areas of the body. Common warts are the most frequent. They consist of whitish papillomatous lesions that can be in any area, oral mucosa, genital mucosa, etc. Most people infected with the genital human papillomavirus are only carriers. It usually has no symptoms and goes away on its own, without causing serious health problems. There is no cure for HPV, but there are treatments for the health problems that some types of HPV can cause, such as genital warts and cervical cancer. Thanks to cytology and histopathology, it can be detected and treated promptly, reducing the impact of this disease. In addition, there are vaccines that promise to reduce this cancer, especially in countries with the highest number of cases. The virus can remain in the body, even after receiving treatment for genital warts. This means that HPV can still be transmitted to sexual partners, despite not having physical manifestations of it. This work will present the bases for the differential detection between the riskiest HPV strains: HPV-18 and HPV-16 through their detection using the amazing idea of Kary Mullis: Polymerase Chain Reaction