The trade-off between cost and performance is a fundamental challenge for modern cloud systems. This thesis explores cost-performance tradeoffs for three types of systems that permeate today’s clouds, namely (1) storage, (2) virtualization, and (3) computation. A distributed key-value storage system must choose between the cost of keeping replicas synchronized (consistency) and performance (lat...

In this paper, a supply chain network design problem is explained which contains environmental concerns in arcs and nodes of network. It is assumed that there are some routes such as road, rail and etc. in each pair of nodes. In this model decision variables are choosing facilities to open, environmental investment level in each facility and flow of products between nodes in each route. A multi...

Natural selection optimizes an organism's genotype within the context of its environment. Adaptations to one environment can decrease fitness in another, revealing evolutionary trade-offs. Here, we show that the cost of gene expression underlies a trade-off between growth rate and mating efficiency in the yeast Saccharomyces cerevisiae. During asexual growth, mutations that eliminate the abilit...

Using a novel and flexible regression approach that avoids imposing restrictive modeling assumptions, we find evidence of a nonmonotonic relation between conditional volatility and expected stock market returns. At low and medium levels of conditional volatility there is a positive risk-return trade-off, but this relation is inverted at high levels of volatility. This finding helps explain the ...

BACKGROUND The decrease in utility attributed to taking pills for cardiovascular prevention can have major effects on the cost-effectiveness of interventions but has not been well studied. We sought to measure the utility of daily pill-taking for cardiovascular prevention. METHODS AND RESULTS We conducted a cross-sectional Internet-based survey of 1000 US residents aged ≥30 in March 2014. We ...

A within-species trade-off between growth rates and lifespan has been observed across different taxa of trees, however, there is some uncertainty whether this trade-off also applies to shade-intolerant tree species. The main objective of this study was to investigate the relationships between radial growth, tree size and lifespan of shade-intolerant mountain pines. For 200 dead standing mountai...