In the process of quantifying optimum seismic design parameters, the losses implying the failure of the system must be assessed. Intangibles such as human lives may lie among indirect losses. In this paper, we propose...In the process of quantifying optimum seismic design parameters, the losses implying the failure of the system must be assessed. Intangibles such as human lives may lie among indirect losses. In this paper, we propose a model to calculate the value of the investment that society should be willing to make for saving lives. In order to do this, we analyze both individual and social problems. However, special treatment is given to the individual problem where the value of the life of a human being is inferred by what the person should be willing to pay or willing to accept to reduce the risk of dying. Due to the use of utility curves in the calculation of this kind of intangible, we pay special attention to shape and requirement conditions of these curves. We also pay attention when personal impact and legacies or bequests are considered in utility curves. The results are shown through some applications, especially in the computation of optimum seismic design coefficients at a low seismicity site.展开更多
In this paper, the addition of admixed superabsorbent polymer (SAP) improved the microstructure and durability-related properties in a cement-based system with supplementary materials. This is an important issue in re...In this paper, the addition of admixed superabsorbent polymer (SAP) improved the microstructure and durability-related properties in a cement-based system with supplementary materials. This is an important issue in real construction projects when good durability properties are required. This study investigates the effect of SAP on the systems using cement replacement by fly ash and silica fume considering the strength properties and durability properties of paste under sulfate attack of cement-based system. The replacement considered in the study was of 10% silica fume and 20% fly ash in each case, the dosage of SAP was 0.25% of the total amount of cementitious material. The results showed that the addition of SAP in the cement-based system improved the compressive strength and reduced expansion to sulfate attack. Scanning electron micrographs showed that utilization of fly ash with silica fume and silica fume with SAP resulted in a much denser microstructure, thereby, leading to an increase in compressive strength and lower expansion under sulfate attack.展开更多
A murine model is used to study qualitatively and quantitatively the splenic ultrastructural changes induced by two <i>Trypanosoma</i><i> </i><i>evansi</i><i> </i>strain...A murine model is used to study qualitatively and quantitatively the splenic ultrastructural changes induced by two <i>Trypanosoma</i><i> </i><i>evansi</i><i> </i>strains derived from naturally infected local equine hosts (<i>Equusasinus</i> and <i>E. caballus</i>);<i>T. evansi</i> causes ultrastructural modifications in the spleen of the infected mice. The modifications include tissular disorganization, fibrosis, mitochondrial swelling, apoptosis and necrosis. The initial phases of the infection are quite similar, whereas the final phases differ qualitatively depending on the strain’s source. The ultrastructural quantitative changes were studied in the reticular splenocytes covering alterations in the area of the cytoplasm and nucleus. Analysis of the results shows the induction of various splenic alterations caused by local <i>T. evansi</i> strains. Also, it was documented that discriminative time modulation, as well as progressive tissular, cellular and subcellular changes, are more associated with derived infections from <i>E. caballus</i> strain.展开更多
The reliability optimization process in earthquake engineering requires that the expected present value of the total cos<span style="color:black;font-family:Verdana;">t is mini</span><span sty...The reliability optimization process in earthquake engineering requires that the expected present value of the total cos<span style="color:black;font-family:Verdana;">t is mini</span><span style="font-family:Verdana;">mized, including the initial cost as well as the damage costs caused by earthquakes, which include indirect costs. One of these costs is concerned with how much society is willing to invest for preserving human life. Ethical principles, on which to base the assessment of this cost, are presented and discussed in this work. Individual and social values are analyzed. Finally, an optimal seismic design coefficient with the results obtained is calculated for a site with low seismicity.</span>展开更多
文摘In the process of quantifying optimum seismic design parameters, the losses implying the failure of the system must be assessed. Intangibles such as human lives may lie among indirect losses. In this paper, we propose a model to calculate the value of the investment that society should be willing to make for saving lives. In order to do this, we analyze both individual and social problems. However, special treatment is given to the individual problem where the value of the life of a human being is inferred by what the person should be willing to pay or willing to accept to reduce the risk of dying. Due to the use of utility curves in the calculation of this kind of intangible, we pay special attention to shape and requirement conditions of these curves. We also pay attention when personal impact and legacies or bequests are considered in utility curves. The results are shown through some applications, especially in the computation of optimum seismic design coefficients at a low seismicity site.
文摘In this paper, the addition of admixed superabsorbent polymer (SAP) improved the microstructure and durability-related properties in a cement-based system with supplementary materials. This is an important issue in real construction projects when good durability properties are required. This study investigates the effect of SAP on the systems using cement replacement by fly ash and silica fume considering the strength properties and durability properties of paste under sulfate attack of cement-based system. The replacement considered in the study was of 10% silica fume and 20% fly ash in each case, the dosage of SAP was 0.25% of the total amount of cementitious material. The results showed that the addition of SAP in the cement-based system improved the compressive strength and reduced expansion to sulfate attack. Scanning electron micrographs showed that utilization of fly ash with silica fume and silica fume with SAP resulted in a much denser microstructure, thereby, leading to an increase in compressive strength and lower expansion under sulfate attack.
文摘A murine model is used to study qualitatively and quantitatively the splenic ultrastructural changes induced by two <i>Trypanosoma</i><i> </i><i>evansi</i><i> </i>strains derived from naturally infected local equine hosts (<i>Equusasinus</i> and <i>E. caballus</i>);<i>T. evansi</i> causes ultrastructural modifications in the spleen of the infected mice. The modifications include tissular disorganization, fibrosis, mitochondrial swelling, apoptosis and necrosis. The initial phases of the infection are quite similar, whereas the final phases differ qualitatively depending on the strain’s source. The ultrastructural quantitative changes were studied in the reticular splenocytes covering alterations in the area of the cytoplasm and nucleus. Analysis of the results shows the induction of various splenic alterations caused by local <i>T. evansi</i> strains. Also, it was documented that discriminative time modulation, as well as progressive tissular, cellular and subcellular changes, are more associated with derived infections from <i>E. caballus</i> strain.
文摘The reliability optimization process in earthquake engineering requires that the expected present value of the total cos<span style="color:black;font-family:Verdana;">t is mini</span><span style="font-family:Verdana;">mized, including the initial cost as well as the damage costs caused by earthquakes, which include indirect costs. One of these costs is concerned with how much society is willing to invest for preserving human life. Ethical principles, on which to base the assessment of this cost, are presented and discussed in this work. Individual and social values are analyzed. Finally, an optimal seismic design coefficient with the results obtained is calculated for a site with low seismicity.</span>