Informal and Nonstandard Employment in the United States: Implications for Low-Income Working Families

Outlines trends in economic activity outside tax and regulatory policies, current focus on formal employment, and policy options for improving the economic well-being of low-income workers such as expanding access to skills training and childcare support

Economic Growth And Child Undernutrition

Sebastian Vollmer and colleagues (April, 2014)1 conclude that “the contribution of economic growth to the reduction in early childhood undernutrition in developing countries is very small, if it exists at all”. Progress will therefore require a shift from “the so-called trickle-down approach of a growth-mediated strategy” to “direct investments in health and nutrition”.

Curve Shortening and the Rendezvous Problem for Mobile Autonomous Robots

If a smooth, closed, and embedded curve is deformed along its normal vector field at a rate proportional to its curvature, it shrinks to a circular point. This curve evolution is called Euclidean curve shortening and the result is known as the Gage-Hamilton-Grayson Theorem. Motivated by the rendezvous problem for mobile autonomous robots, we address the problem of creating a polygon shortening flow. A linear scheme is proposed that exhibits several analogues to Euclidean curve shortening: The polygon shrinks to an elliptical point, convex polygons remain convex, and the perimeter of the polygon is monotonically decreasing.Comment: 15 pages, 18 figure

Propaganda, Xenophobia, and the First Amendment

Not available

Propaganda, Xenophobia, and the First Amendment

Not available

CONTINGENT VALUATION FOCUS GROUPS: INSIGHTS FROM ETHNOGRAPHIC INTERVIEW TECHNIQUES

Despite the many important uses (and potential abuses) of focus groups in survey design, the CV literature presents few guidelines to aid moderators in their interaction with focus group participants. This paper draws on the theory and practice of ethnographic interviewing to introduce general guidelines that can improve focus groups as an aid to CV research. The proposed guidelines illustrate types of questions that should reduce speculation and moderator-introduced bias in focus group responses, and improve the correspondence between focus group responses and actual behavior. The paper illustrates these ethnographic guidelines through a CV application concerning watershed resources.Research Methods/ Statistical Methods,

On-line replacement of program modules using AdaPT

One purpose of our research is the investigation of the effectiveness and expressiveness of AdaPT(1), a set of language extensions to Ada 83, for distributed systems. As a part of that effort, we are now investigating the subject of replacing, e.g., upgrading, software modules while the software system remains in operation. The AdaPT language extension provide a good basis for this investigation for several reasons: (1) they include the concept of specific, self-contained program modules which can be manipulated; (2) support for program configuration is included in the language; and (3) although the discussion will be in terms of the AdaPT language, the AdaPT to Ada 83 conversion methodology being developed as another part of this project will provide a basis for the application of our findings to Ada 83 systems. The purpose of this investigation is to explore the basic mechanisms to the replacement process. Thus, while replacement in the presence of real-time deadlines, heterogeneous systems, and unreliable networks is certainly a topic of interest, we will first gain an understanding of the basic processes in the absence of such concerns. The extension of the replacement process to more complex situations can be made later. This report will establish an overview of the on-line upgrade problem, and present a taxonomy of the various aspects of the replacement process

Comprehensive simulations of superhumps

(Abridged) We use 3D SPH calculations with higher resolution, as well as with more realistic viscosity and sound-speed prescriptions than previous work to examine the eccentric instability which underlies the superhump phenomenon in semi-detached binaries. We illustrate the importance of the two-armed spiral mode in the generation of superhumps. Differential motions in the fluid disc cause converging flows which lead to strong spiral shocks once each superhump cycle. The dissipation associated with these shocks powers the superhump. We compare 2D and 3D results, and conclude that 3D simulations are necessary to faithfully simulate the disc dynamics. We ran our simulations for unprecedented durations, so that an eccentric equilibrium is established except at high mass ratios where the growth rate of the instability is very low. Our improved simulations give a closer match to the observed relationship between superhump period excess and binary mass ratio than previous numerical work. The observed black hole X-ray transient superhumpers appear to have systematically lower disc precession rates than the cataclysmic variables. This could be due to higher disc temperatures and thicknesses. The modulation in total viscous dissipation on the superhump period is overwhelmingly from the region of the disc within the 3:1 resonance radius. As the eccentric instability develops, the viscous torques are enhanced, and the disc consequently adjusts to a new equilibrium state, as suggested in the thermal-tidal instability model. We quantify this enhancement in the viscosity, which is ~10 per cent for q=0.08. We characterise the eccentricity distributions in our accretion discs, and show that the entire body of the disc partakes in the eccentricity.Comment: 18 pages (mn2e LaTeX), 14 figures, 5 tables, Accepted for publication in MNRA

ANALYSIS OF THE SPATIAL DISTRIBUTION OF SUGARBEET PLANTS

The spatial distribution of emerged sugarbeet plants is an important aspect of the performance of sugarbeet planters. Three major components influencing the spatial distribution are the ability to drop a single seed at a time, the ability to drop the seeds a fixed distance apart, and the ability of the seed to emerge. A model has been developed to describe the distribution of the spacing between emerged sugarbeet plants. The model consists of a mixture of normal and gamma distributions. The spatial data consists of the distance between neighboring emerged plants. Spatial data was collected on 7 planters operated at 3 speeds using both pelleted and encrusted seeds. Four replicates were obtained of each treatment combination. Approximate maximum likelihood estimates of the parameters were obtained separately for each replicate of the treatment combinations