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Permanent sliding displacements are used to evaluate the seismic stability of earth slopes, and current practice utilizes a pseudoprobabilistic approach to predict the expected sliding displacement. The pseudoprobabilistic approach specifies a design ground-motion level based on a probabilistic seismic hazard analysis and a specified hazard level (e.g., 2% probability of exceedance in 50?years), but the displacement is predicted deterministically based on the design ground-motion level. The fully probabilistic approach develops a hazard curve for sliding displacement, and it is used to assess the displacement of the slope for a given hazard level. Comparisons of the fully probabilistic and pseudoprobabilistic approaches indicate that the pseudoprobabilistic analysis provides nonconservative estimates of sliding displacement in most cases. This paper presents a modification to the pseudoprobabilistic approach that provides displacement values more consistent with the fully probabilistic approach. This modification involves specifying a displacement greater than the median, in order to take into account the uncertainty in the displacement prediction. The appropriate value of displacement above the median is a function of the ky/PGA value and the model used to predict the displacement. 相似文献
105.
In this study, a DEA based Malmquist index model was developed to assess the relative efficiency and productivity of U.S. states in decreasing the number of road fatalities. Even though the national trend in fatal crashes has reached to the lowest level since 1949 (Traffic Safety Annual Assessment Highlights, 2010), a state-by-state analysis and comparison has not been studied considering other characteristics of the holistic national road safety assessment problem in any work in the literature or organizational reports. In this study, a DEA based Malmquist index model was developed to assess the relative efficiency and productivity of 50 U.S. states in reducing the number of fatal crashes. The single output, fatal crashes, and five inputs were aggregated into single road safety score and utilized in the DEA-based Malmquist index mathematical model. The period of 2002–2008 was considered due to data availability for the inputs and the output considered. According to the results, there is a slight negative productivity (an average of −0.2 percent productivity) observed in the U.S. on minimizing the number of fatal crashes along with an average of 2.1 percent efficiency decline and 1.8 percent technological improvement. The productivity in reducing the fatal crashes can only be attributed to the technological growth since there is a negative efficiency growth is occurred. It can be concluded that even though there is a declining trend observed in the fatality rates, the efficiency of states in utilizing societal and economical resources towards the goal of zero fatality is not still efficient. More effective policy making towards increasing safety belt usage and better utilization of safety expenditures to improve road condition are derived as the key areas to focus on for state highway safety agencies from the scope of current research. 相似文献
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Pomegranate juices obtained from ten pomegranate cultivars of Turkey were analysed for their sugars, organic acids and the other quality parameters including pH, total soluble solids, and titratable acidity. Statistically significant differences were determined among the cultivars for parameters analysed. Citric acid was the predominant acid of all the cultivars studied. Cultivar “Zivzik,” one of the most popular cultivar in Turkey, showed best scores for total soluble solids (16.9 ± 0.06 °Brix), glucose (84.18 ± 0.42 g/l) and fructose (83.34 ± 0.81 g/l). Pomegranate juices were classified into three groups according to principal component analysis and cluster analysis. 相似文献
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Tapan Behl Rashita Makkar Aayush Sehgal Sukhbir Singh Neelam Sharma Gokhan Zengin Simona Bungau Felicia Liana Andronie-Cioara Mihai Alexandru Munteanu Mihaela Cristina Brisc Diana Uivarosan Ciprian Brisc 《International journal of molecular sciences》2021,22(14)
The human body is highly complex and comprises a variety of living cells and extracellular material, which forms tissues, organs, and organ systems. Human cells tend to turn over readily to maintain homeostasis in tissues. However, postmitotic nerve cells exceptionally have an ability to regenerate and be sustained for the entire life of an individual, to safeguard the physiological functioning of the central nervous system. For efficient functioning of the CNS, neuronal death is essential, but extreme loss of neurons diminishes the functioning of the nervous system and leads to the onset of neurodegenerative diseases. Neurodegenerative diseases range from acute to chronic severe life-altering conditions like Parkinson’s disease and Alzheimer’s disease. Millions of individuals worldwide are suffering from neurodegenerative disorders with little or negligible treatment available, thereby leading to a decline in their quality of life. Neuropathological studies have identified a series of factors that explain the etiology of neuronal degradation and its progression in neurodegenerative disease. The onset of neurological diseases depends on a combination of factors that causes a disruption of neurons, such as environmental, biological, physiological, and genetic factors. The current review highlights some of the major pathological factors responsible for neuronal degradation, such as oxidative stress, cell death, and neuroinflammation. All these factors have been described in detail to enhance the understanding of their mechanisms and target them for disease management. 相似文献
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Ermis M. Acik A. Gultekin B. Terciyanli A. Nalcaci E. Cadirci I. Ozay N. Ermis C. Gokmen M. Kiziltan H. 《Industry Applications, IEEE Transactions on》2004,40(6):1644-1655
This paper describes the solution of power quality problems arising from 12-pulse smelter converters in the ETI Aluminum Works, Seydis$80ehir, Turkey. The design work is based on practical data collected in the field as well as on the results of detailed simulation studies obtained by EMTDC/PSCAD, SPICE, and MATLAB. The main design objective is to meet both present regulations and harmonic standards by using robust, reliable, and cost-effective systems with a long life expectancy. The shunt-connected passive reactive power compensation system is composed of a damped 11th harmonic filter and a make-up filter tuned to the 5th harmonic with optional damping resistor. Such a system exhibits nearly transient-free switching and series-resonance proof characteristics owing to damping resistors. A close correlation has been obtained between theoretical results and field data. 相似文献
110.
The SnS activities in liquid Ag2S-SnS liquid mattes were obtained at 1100 °C and 1200 °C by the dew-point method. Negative deviations were observed, and the
liquid matte solutions were modeled by the Wilson equations. Part of the liquid boundaries of the Ag2S-SnS phase diagram were derived from the model equations, yielding a eutectic temperature of 528 °C at x
SnS=0.38. The phase diagram of the pseudobinary Ag2S-SnS was also verified experimentally by quenching samples equilibrated in evacuated and sealed silica capsules. Solubility
limits of the components at the narrow-terminal solid-solution ranges were determined around the eutectic temperature. Within
the Ag-Sn-S ternary system, the boundaries of the immiscibility region, together with the tie-line distributions, were established
at 1200 °C. Activities of Ag, Sn, and S along the miscibility gap were calculated by utilizing the bounding binary thermodynamics,
phase equilibria, and tie-lines. 相似文献