Cloud Index Tracking: Enabling Predictable Costs in Cloud Spot Markets

Cloud spot markets rent VMs for a variable price that is typically much lower than the price of on-demand VMs, which makes them attractive for a wide range of large-scale applications. However, applications that run on spot VMs suffer from cost uncertainty, since spot prices fluctuate, in part, based on supply, demand, or both. The difficulty in predicting spot prices affects users and applications: the former cannot effectively plan their IT expenditures, while the latter cannot infer the availability and performance of spot VMs, which are a function of their variable price. To address the problem, we use properties of cloud infrastructure and workloads to show that prices become more stable and predictable as they are aggregated together. We leverage this observation to define an aggregate index price for spot VMs that serves as a reference for what users should expect to pay. We show that, even when the spot prices for individual VMs are volatile, the index price remains stable and predictable. We then introduce cloud index tracking: a migration policy that tracks the index price to ensure applications running on spot VMs incur a predictable cost by migrating to a new spot VM if the current VM's price significantly deviates from the index price.Comment: ACM Symposium on Cloud Computing 201

CM Values of Green Functions Associated to Special Cycles on Shimura Varieties with Applications to Siegel 3-Fold X2(2)X_2(2)

We generalize the definition of CM cycles beyond the small and big CM ones studied by various authors and give a uniform formula for the CM values of Green functions associated to these special cycles in general using the idea of regularized theta lifts. Finally, as an application to Siegel 3-fold $X_2(2)$, we can compute special values of theta functions and Rosenhain $\lambda$-invariants at a CM cycle, which is useful for genus two curve cryptography.Comment: arXiv admin note: text overlap with arXiv:1008.1669 by other author

Collinear and Transverse Momentum Dependent parton densities obtained with a Parton Branching Method

We present a solution of the DGLAP evolution equations, written in terms of Sudakov form factors to describe the branching and no-branching probabilities, using a parton branching Monte Carlo method. We demonstrate numerically that this method reproduces the semi-analytical solutions. We show how this method can be used to determine Transverse Momentum Dependent (TMD) parton distribution functions, in addition to the usual integrated parton distributions functions. We discuss numerical effects of the boundary of soft gluon resolution scale parameter on the resulting parton distribution functions. We show that a very good fit of the integrated TMDs to high precision HERA data can be obtained over a large range in x and Q^2

Doing More for Our Children: Modeling a Universal Child Allowance or More Generous Child Tax Credit

Child poverty in the United States remains stubbornly high, with 12.2 million children living in poverty in 2013. Nearly 17 percent of children in the United States lived in poverty in 2013 -- a higher rate than for other age groups, and considerably higher than the child poverty rate in other advanced industrialized countries. The U.S. deep child poverty rate -- children who live in families with incomes less than half of the poverty line -- was 4.5 percent of all children in 2013, meaning nearly 1 in 20 children live in families that cannot even afford half of what is considered a minimally adequate living.One key policy for reducing child poverty is the child tax credit (CTC) -- which reduces the child poverty rate from 18.8 percent to 16.5 percent of American children. There is broad acceptance of the importance of the CTC, and key expansions to the CTC were made permanent at the end of 2015. At a moment when leaders ranging from President Barack Obama to Speaker Paul Ryan are talking about poverty, now is an opportune time to explore policy options that would build on this success. This report models two approaches to reduce child poverty in the United States even further -- a universal child allowance and an expanded CTC.A universal child allowance is a cash benefit that is provided to all families with children without regard to their income, earnings, or other qualifying conditions, and that could be subject to taxes for families with high incomes. The U.S. child tax credit, in contrast, is provided only to families that meet a threshold for earnings, phasing in as earnings increase and then phasing out as earnings rise higher. While most other advanced industrialized countries have some kind of universal support for children, the United States does not.For each approach, we begin with a modest reform, and then model increasingly generous versions. In our simulations, we find that even the modest reforms generate important poverty reductions. Our results also make clear that the more we spend on these programs, the greater the reduction in poverty the United States can achieve

Curriculum Re-definitions and Transformations: Spinning on New Axes within the Technological University

Within a technological university there is an understanding of the kind of education students should possess on graduation. A primary consideration in such an institution is the requirement to transmit knowledge and universal values and, at the same time, to contribute to the cultural, economic and social development of the local societies that they serve and that support them . This paper explores how a curriculum can be (re)shaped in a technological university context to address this requirement. This paper develops and examines a possible pathway to progress the establishment of a portfolio of academic programmes within the context of establishing a technological university by: 1. developing a set of principles which can be used to review existing programme portfolios; 2. identifying a process which can be deployed to develop a cooperative model within each discipline to develop the portfolio of programmes while applying the general principle as listed at (1) above. By transforming its curriculum the technological university will fulfil its public service obligation to develop civic competence through the pursuit of research-that-creates- knowledge, education-as-the-sharing-of-knowledge, and innovation-as-commitment to engagement with clients whose focus is the local, regional, national, and international development of Irish higher education