Survivable algorithms and redundancy management in NASA's distributed computing systems

The design of survivable algorithms requires a solid foundation for executing them. While hardware techniques for fault-tolerant computing are relatively well understood, fault-tolerant operating systems, as well as fault-tolerant applications (survivable algorithms), are, by contrast, little understood, and much more work in this field is required. We outline some of our work that contributes to the foundation of ultrareliable operating systems and fault-tolerant algorithm design. We introduce our consensus-based framework for fault-tolerant system design. This is followed by a description of a hierarchical partitioning method for efficient consensus. A scheduler for redundancy management is introduced, and application-specific fault tolerance is described. We give an overview of our hybrid algorithm technique, which is an alternative to the formal approach given

A Model for Collaboration and Results: How Cross-agency Collaboration Helped Hampton, Va., Build a Broad Array of Child and Family Services

This report highlights the highly successful experiences of child-serving agencies that are collaborating in Hampton, Virginia, to achieve better outcomes for children and Families. Hampton exemplifies how child-serving agencies can cooperate to sreve children in their communities. By emphasizing prevention and building a smart array of services and supports, more of Hampton's children live with their families, safe and thriving, reducing the need for child welfare or juvenile justice group placements

Reliable Communication in a Dynamic Network in the Presence of Byzantine Faults

We consider the following problem: two nodes want to reliably communicate in a dynamic multihop network where some nodes have been compromised, and may have a totally arbitrary and unpredictable behavior. These nodes are called Byzantine. We consider the two cases where cryptography is available and not available. We prove the necessary and sufficient condition (that is, the weakest possible condition) to ensure reliable communication in this context. Our proof is constructive, as we provide Byzantine-resilient algorithms for reliable communication that are optimal with respect to our impossibility results. In a second part, we investigate the impact of our conditions in three case studies: participants interacting in a conference, robots moving on a grid and agents in the subway. Our simulations indicate a clear benefit of using our algorithms for reliable communication in those contexts

Privatization and State Capacity in Postcommunist Society

Economists have used cross-national regression analysis to argue that postcommunist economic failure is the result of inadequate adherence liberal economic policies. Sociologists have relied on case study data to show that postcommunist economic failure is the outcome of too close adherence to liberal policy recommendations, which has led to an erosion of state effectiveness, and thus produced poor economic performance. The present paper advances a version of this statist theory based on a quantitative analysis of mass privatization programs in the postcommunist world. We argue that rapid large-scale privatization creates severe supply and demand shocks for enterprises, thereby inducing firm failure. The resulting erosion of tax revenues leads to a fiscal crisis for the state, and severely weakens its capacity and bureaucratic character. This, in turn, reacts back on the enterprise sector, as the state can no longer support the institutions necessary for the effective functioning of a modern economy, thus resulting in deindustrialization. Using cross-national regression techniques we find that the implementation of mass privatization programs negatively impacts measures of economic growth, state capacity and the security of property rights.http://deepblue.lib.umich.edu/bitstream/2027.42/40192/3/wp806.pd

Comparative Federalism meets the European Union

In the current debate on the future European order, the European Union is often described as an emerging federation. The paper claims that federalism is not only useful in deliberating about the future of the European Union. It provides a better understanding of the current structure and functioning of the European system of multilevel governance than most theories of European integration. We combine political and economic perspectives of federalism to analyze the balancing act between effective political representation and efficient policy-making in the European Union. Drawing on the examples of Germany and Switzerland in particular, we argue that the increasing delegation of powers to the central EU level needs to be paralleled by either strengthened patterns of fiscal federalism or an empowered representation of functional interests at the European level. Without such "re-balancing", the current legitimacy problems of EU are likely to get worse.federalism; multilevel governance; multilevel governance; political representation; interest representation; democracy

Medium-run macrodynamics and the consensus view of stabilization policy

Policy implications of the present consensus view of stabilization policy depend on specific assumptions with regard to the equilibrium level of production. Thereby, the interpretation of equilibrium output rests on a separation of supply-side and demandside adjustment to macroeconomic shocks promoting a dichotomy of short-term and long-term macrodynamics. In contrast to this, there are several channels that promote procyclical stimulus of aggregate demand and a changing factor utilization to the accumulation and efficiency of an economy’s productive capacity. Medium-run macrodynamics call for a rather endogenous explanation of production capacity and challenge the uniqueness of long-term equilibria.Monetary policy, medium-run macrodynamics, long-term nonneutrality, capacity utilization.