SUMMARY This study focuses on the development of vulnerability functions for tall buildings. A systematic simulation approach based on the Pacific Earthquake Engineering Research loss assessment framework is used to develop building vulnerability functions that provide estimates of losses to buildings under ground motions of various intensities. The steps involved in the procedure are: quantifying ground‐motion hazard using a vector of spectral accelerations; predicting building response parameters such as story drifts, floor accelerations, and residual drifts under the quantified hazard; accounting for structural collapse and demolition; and predicting story‐wise losses and total building loss using the building response information. Emphasis is placed on capturing the effects of epistemic and aleatory uncertainties in random variables, such as ground motions, structural response parameters, loss costs, etc., to quantify the uncertainty in the final loss estimate. The risk assessment approach is used for developing vulnerability functions for six tall buildings, namely, 20‐story and 40‐story steel moment resisting frame buildings based on 1973 and 2006 codes, a 42‐story concrete core wall building and a 42‐story concrete dual system building. The vulnerability functions are used to perform loss assessments for individual buildings assumed to be located in Los Angeles. The vulnerability and the loss assessment procedures are illustrated in detail for the 2006 20‐story steel moment frame building, and a summary of the final loss estimates are provided for all other buildings. It is seen that epistemic uncertainties in both ground motion hazard and building vulnerability cause significant epistemic uncertainties in the loss assessment results. Copyright © 2012 John Wiley & Sons, Ltd.

Quinazolinones are a group of heterocyclic compounds that have important biological activities such as cytotoxicity, anti-bacterial, and anti-fungal effects. Thiazole-containing compounds have also many biological effects including antitumor, antibacterial, anti-inflammatory, and analgesic activities. Due to significant cytotoxic effects of both quinazoline and thiazole derivatives, in this work a group of quinazolinone-thiazol hybrids were prepared and their cytotoxic effects on three cell lines were evaluated using MTT assay. Compounds A3, A2, B4, and A1 showed highest cytotoxic activities against PC3 cell line. Compounds A3, A5, and A2 were most active against MCF-7 and A3, A5, and A6 showed good cytotoxic effect on HT-29 cell line. According to the results, A3 efficiently inhibited all cell growth tested in a dose dependent manner. The IC50 of A3 was 10 M, 10 μM, and 12 μM on PC3, MCF-7, and HT-29 cells, respectively.

As part of the PEER Center's tall building initiative (TBI) project, practicing engineers designed three structural systems, each based on commonly used codes and guidelines in addition to the guidelines developed by PEER. The designs were analyzed by three research teams, using a set of 75 ground-motion pairs, to predict response parameters for evaluating the performance of tall buildings. This study focuses on analytically estimating the seismic losses to these buildings to assess their relative seismic performance. The loss assessment process follows a comprehensive simulation approach which takes into account several random variables such as building response, repair costs, etc. Throughout this study, epistemic and aleatory uncertainties in the random variables are accounted for, in order to quantify those in loss estimates. Based on the dollar loss results, the performance of the dual-system building is compared and contrasted with that of the other building systems considered in the PEER study.

SUMMARY Earthquake catastrophe models provide probabilistic estimations of building portfolio losses that result from seismic hazards. Models that are designed to be used with large numbers of buildings often implicitly account for uncertainty associated with model components, but do not allow for an explicit comparison of different sources of uncertainty. We propose probabilistic methodologies that allow for explicit differentiation of the uncertainty in estimated portfolio losses as a function of the uncertainties associated with seismic hazard and building vulnerability. Our work is motivated by recent earthquakes in New Zealand and Japan, which highlighted the importance of understanding the sources of uncertainty that contribute to portfolio‐level loss estimates. The proposed methodologies allow us to differentiate seismic risk between building portfolios as a function of the level of knowledge (epistemic) uncertainty associated with modeling seismic rates and the levels of aleatory variability and epistemic uncertainty associated with the buildings' vulnerabilities. A sample analysis incorporates epistemic uncertainty corresponding to Southern California's seismic rates into modeled losses for a Southern California building portfolio and then compares the impact of that particular source of uncertainty to the results from a portfolio in Northern California. For sources of uncertainty associated with buildings' vulnerability, we use our methodology to compare the impacts of aleatory and epistemic uncertainties on estimated portfolio losses as a function of the buildings' attributes, including their types of construction and numbers of stories. Component uncertainties (i.e., uncertainties corresponding to the seismic hazard and vulnerability) are assumed for our analyses so that the methodologies can be demonstrated. Copyright © 2012 John Wiley & Sons, Ltd.

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