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41.
Disaster management systems are complex applications due to their distributed and decentralized nature. Various components execute in parallel with high need of coordination with each other. In such applications, interaction and communication issues are difficult to model and implement. In this paper, we have proposed agent-based Earthquake Management System (EMS) which is modeled and analyzed using formal approach. Traditionally, such systems undergo through various transformations starting from requirement models and specification to analysis, design and implementation. A variety of formal approaches are available to specify systems for analyzing their structure and behavior; however, there are certain limitations in using these techniques due to their expressiveness and behavior requirements. We have adopted combination of Pi-calculus and Pi-ADL formal languages to model EMS from analysis to design. The formal approach helps to enhance reliability and flexibility of the system by reducing the redundant information. It reduces chances of errors by explicitly mentioning working flow of information. Additionally, a prototype application is presented as proof of concept in EMS context. We have also evaluated our formal specification by using ArchWare and ABC tools; also, comparison of prototype application with major existing techniques is highlighted.  相似文献   
42.
ENERGY AND GDP     
Understanding of the role of energy use at the national level requires the understanding of the relationship of energy use to economic activity and social well-being. Gross domestic product (GDP) measures the value of goods and services produced in a country in one year. There is a close relationship between energy supply, energy consumption, and GDP, which indicates the economic development of a country. The living standard of a country is often measured by the per capita GDP. This article presents the evaluations and future projections of energy and energy resources of the Organization for Economic Cooperation and Development (OECD). The total primary energy supply, total final energy consumption, and energy intensities for supply and consumption are analysed. The energy data for all OECD countries are presented and analyses of the differences in energy and GDP ratios are conducted at an aggregate level by examining differences in the factors that affect the energy intensities. To provide accurate projections for the future, new correlations are developed between average GDP, total primary energy supply, total final consumption, total per capita primary energy supply, total per capita final consumption and total OECD population. © 1997 by John Wiley & Sons, Ltd.  相似文献   
43.
The article presents a simple technique for the purpose of heat and mass transfer analysis in an ACS. The LiBr/water ACS was selected as an example. based on optimum operation conditions (i.e., the maximum cooling temperature delivered by the ACS), simple but effective expression were derived in terms of the mass flow rate of absorbent—the most important parameter for practical design calculations. The results show that the proposed technique provides, for practical application purposes, a useful tool for a general analysis of the ACS as well as for the system design purpose.  相似文献   
44.
The mechanisms of antibody–antigen (Ab–Ag) interactions at conducting polypyrrole electrodes have been investigated using impedance spectroscopy techniques. The effects of the variation in ion exchange, solution composition, and the condition of the synthesis have been used to study the capacitive behavior of antibody-containing polypyrrole electrodes in the presence of the antigen. The theory of charge generation and transportation in the heterogeneous polymeric domains is proposed as the predominant basis for the analytical signals observed at these electrodes. The significant difference observed in the impedance response at different potentials confirmed that the Ab–Ag interaction was largely influenced by the applied potential.  相似文献   
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Species distribution, virulence traits and vancomycin resistance gene profiles of Enterococcus isolated from 43 home‐made artisan cheese samples collected from open markets, located in Aydin region of Turkey, were investigated. Of the 129 isolates, 95 were identified as Enterococcus sp.; Enterococcus faecium being the most prevalent species (82.1%), followed by Enterococcus faecalis (13.6%) and Enterococcus durans (1.0%). None of the enterococci were harbouring vanA or vanC, while seven isolates (7.3%) were shown to harbour vanB gene by multiplex PCR. gelE (49.4%) being the most prevalent virulence factor was followed by asa1 (27.3%), esp (22.1%), cylA (4.2%) and hyl (3.1%).  相似文献   
48.
The nanoscale surface features of lipid‐coated microbubbles can dramatically affect how the lipids interact with one another as the microbubble diameter expands and contracts under the influence of ultrasound. During microbubble manufacturing, the different lipid shell species naturally partition forming concentrated lipid islands. In this study the dynamics of how these nanoscale islands accommodate the expansion of the microbubbles are monitored by measuring the fluorescence intensity changes that occur as self‐quenching lipophilic dye molecules embedded in the lipid layer change their distance from one another. It was found that when the dye molecules were concentrated in islands, less than 5% of the microbubbles displayed measurable fluorescence intensity modulation indicating the islands were not able to expand sufficiently for the dye molecules to separate from one another. When the microbubbles were heated and cooled rapidly through the lipid transition temperature the islands were melted creating an even distribution of dye about the surface. This resulted in over 50% of the microbubbles displaying the fluorescence‐modulated signal indicating that the dye molecules could now separate sufficiently to change their self‐quenching efficiency. The separation of the surface lipids in these different formations has significant implications for microbubble development as ultrasound and optical contrast agents.  相似文献   
49.
In this paper the propagation of acceleration waves arbitrary form propagating into a deformed eleastic dielectric with polarization effect is investigated. An acceleration wave is defined as a second order propagating surface of discontinuity on which the position vector, the polarization vector and Maxwell potential, and their first order derivatives with respect to time and space coordinates are continuous while the second order derivatives of these quantities may suffer jumps but are continuous everywhere else. By computing the jumps of the balance equations on the singular surface, implicit equations for wave speeds corresponding to non-zero amplitudes of the acceleration wave are obtained. It is noteworthy that the second order derivatives of Maxwell potential are also continuous across the acceleration wave.The same equation for wave speeds are also derived for isotropic elastic dielectrics. The wave speeds for longitudinal and transverse waves are obtained in explicit forms and the conditions of existence for real wave speeds are investigated.  相似文献   
50.
The aim of the present study was to determine the level of antibiotic resistance patterns and distribution of heavy metal resistance of bacterial isolates from seawater, sediment and shrimps, and to determine if there is a relationship between antibiotic and heavy metal resistance. We undertook studies in 2007 in the industrially polluted Iskenderun Bay, on the south coast of Turkey. The resistance of 236 Gram-negative bacterial isolates (49 from seawater, 90 from sediment and 97 from shrimp) to 16 different antibiotics, and to 5 heavy metals, was investigated by agar diffusion and agar dilution methods, respectively. A total of 31 species of bacteria were isolated: the most common strains isolated from all samples were Escherichia coli (11.4%), Aeromonas hydrophila (9.7%) and Stenotrophomonas maltophilia (9.3%). There was a high incidence of resistance to ampicillin (93.2%), streptomycin (90.2%) and cefazolin (81.3%), and a low incidence of resistance to imipenem (16.5%), meropenem (13.9%) and cefepime (8.0%). Some 56.8% of all bacteria isolated from seawater, sediment and shrimp were resistant to 7 or more antibiotics. Most isolates showed tolerance to different concentrations of heavy metals, and minimal inhibition concentrations ranged from 12.5 μg/ml to > 3200 μg/ml. The bacteria from seawater, sediment and shrimp showed high resistance to cadmium of 69.4%, 88.9%, and 81.1% respectively, and low resistance to manganese of 2%, 6.7% and 11.3% respectively. The seawater and sediment isolates which were metal resistant also showed a high resistance to three antibiotics: streptomycin, ampicillin and trimethoprim-sulphamethoxazole. In contrast, the shrimp isolates which were metal resistant were resistant to four antibiotics: cefazolin, nitrofurantoin, cefuroxime and ampicillin. Our results show that Iskenderun Bay has a significant proportion of antibiotic and heavy metal resistant Gram-negative bacteria, and these bacteria constitute a potential risk for public health.  相似文献   
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