The Emergence of Transitional Justice in the United States via the Criminal Justice System

The definition of transitional justice includes police and judiciary reform in part through truth and reconciliation commissions. Several states have operational truth and justice commissions, and there are clear Congressional and media indications of a United States truth and reconciliation commission. The purpose of this paper is to explore a national truth and justice commission with a focus on criminal justice reform. The South African Truth and Reconciliation Commission will be explored, and its potential implications for such a United States commission. The United States Supreme Court decision McGirt v. Oklahoma (2020) will also be highlighted as it may have implications for reparations similar to those proposed in South Africa

The Devil's in the Tail: Residential Mortgage Finance and the U.S. Treasury

This paper seeks to contribute to the U.S. housing finance reform conversation by providing a critical assessment of the various types of policy proposals that have been offered. There appears to be a broad consensus to maintain explicit government guarantees for certain narrowly defined borrower populations, such as FHA insurance guarantees for low- and moderate-income and first-time homebuyers. However, the expected role of the federal government in the broader housing finance system is in dispute: ranging from no role; to insuring against only extreme or tail events; to insuring against all losses. However, most proposals agree that any public insurance be priced and available only for loans meeting pre-specified criteria in an effort to limit taxpayer exposure

The Optimal Projection Equations for Fixed-Order Sampled-Data Dynamic Compensation with Computation Delay

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/57876/1/FixedOrderSampledData.pd

Statistical Confirmation of Empirical Observations Concerning Tool Mark Striae

Toolmarks produced by 44 sequentially manufactured screwdriver tips have been characterized for surface roughness using a profilometer. Toolmarks were produced in lead at angles of 30°, 60°, and 85°. A computer program developed to compare and match the profilometer data has been used to show that marks from a single tip produced at similar angles yield much higher correlation values than marks produced from the same tip but at different angles. This analysis provides statistical support for the widely-accepted empirical observation that toolmark striae must be reproduced at similar angles in order to be unambiguously identified as being made by a particular tool

What have we already learned from the CMB?

The COBE satellite, and the DMR experiment in particular, was extraordinarily successful. However, the DMR results were announced about 7 years ago, during which time a great deal more has been learned about anisotropies in the Cosmic Microwave Background (CMB). The CMB experiments currently being designed and built, including long-duration balloons, interferometers, and two space missions, promise to address several fundamental cosmological issues. We present our evaluation of what we already know, what we are beginning to learn now, and what the future may bring.Comment: 20 pages, 3 figures. Changes to match version accepted by PAS

A Numerical Relativity Waveform Surrogate Model for Generically Precessing Binary Black Hole Mergers

A generic, non-eccentric binary black hole (BBH) system emits gravitational waves (GWs) that are completely described by 7 intrinsic parameters: the black hole spin vectors and the ratio of their masses. Simulating a BBH coalescence by solving Einstein's equations numerically is computationally expensive, requiring days to months of computing resources for a single set of parameter values. Since theoretical predictions of the GWs are often needed for many different source parameters, a fast and accurate model is essential. We present the first surrogate model for GWs from the coalescence of BBHs including all $7$ dimensions of the intrinsic non-eccentric parameter space. The surrogate model, which we call NRSur7dq2, is built from the results of $744$ numerical relativity simulations. NRSur7dq2 covers spin magnitudes up to $0.8$ and mass ratios up to $2$, includes all $\ell \leq 4$ modes, begins about $20$ orbits before merger, and can be evaluated in $\sim~50\,\mathrm{ms}$. We find the largest NRSur7dq2 errors to be comparable to the largest errors in the numerical relativity simulations, and more than an order of magnitude smaller than the errors of other waveform models. Our model, and more broadly the methods developed here, will enable studies that would otherwise require millions of numerical relativity waveforms, such as parameter inference and tests of general relativity with GW observations.Comment: 10 pages, 5 figures; Added report numbe

Radioisotope Heater Unit-Based Stirling Power Convertor Development at NASA Glenn Research Center

Stirling Radioisotope Power Systems (RPS) are being developed as an option to provide power on future space science missions where robotic spacecraft will orbit, flyby, land or rove. A variety of mission concepts have been studied by NASA and the U. S. Department of Energy that would utilize RPS for landers, probes, and rovers and only require milliwatts to tens of watts of power. These missions would contain science measuring instruments that could be distributed across planetary surfaces or near objects of interest in space solar flux insufficient for using solar cells. A low power Stirling convertor is being developed to provide an RPS option for future low power applications. Initial concepts convert heat available from several Radioisotope Heater Units to electrical power for spacecraft instruments and communication. Initial development activity includes defining and evaluating a variety of Stirling configurations and selecting one for detailed design, research of advanced manufacturing methods that could simplify fabrication, evaluating thermal interfaces, characterizing components and subassemblies to validate design codes, and preparing for an upcoming demonstration of proof of concept in a laboratory environment