Predicted and tested performance of durable TPS

The development of thermal protection systems (TPS) for aerospace vehicles involves combining material selection, concept design, and verification tests to evaluate the effectiveness of the system. The present paper reviews verification tests of two metallic and one carbon-carbon thermal protection system. The test conditions are, in general, representative of Space Shuttle design flight conditions which may be more or less severe than conditions required for future space transportation systems. The results of this study are intended to help establish a preliminary data base from which the designers of future entry vehicles can evaluate the applicability of future concepts to their vehicles

Symmetrized mean-field description of magnetic instabilities in k-(BEDT-TTF)_2Cu[N(CN)]_2 Y salts

We present a novel and convenient mean-field method, and apply it to study the metallic/antiferromagnetic interface of k-(BEDT-TTF)_2Cu[N(CN)]_2 Y organic superconductors (BEDT_TTF is bis-ethylen-dithio-tetrathiafulvalene, Y=Cl, Br). The method, which fully exploits the crystal symmetry, allows one to obtain the mean-field solution of the 2D Hubbard model for very large lattices, up to 6x10^5 sites, yielding a reliable description of the phase boundary in a wide region of the parameter space. The metal/antiferromagnet transtion appears to be second order, except for a narrow region of the parameter space, where the transition is very sharp and possibly first order. The cohexistence of metallic and antiferromagnetic properties is only observed for the transient state in the case of smooth second order transitions. The relevance of the present resaults to the complex experimental behavior of centrosymmetric k-phase BEDT-TTF salts is discussed.Comment: 9 pages in PS format, 7 figures (included in PS), 1 tabl

The economic impact of broadband deployment in Kentucky

Significant resources are being invested by government and the private sector in broadband infrastructure to increase broadband deployment and use. With a unique dataset of broadband availability (sorted by county), the authors assess whether broadband infrastructure has affected the industrial competitiveness of Kentucky counties. Their results suggest that broadband availability increases employment growth in some industries but not others.Economic development ; Kentucky

Methods for Estimating Economic Damages from Environmental Contamination

While significant attention has been given to the decrease in property values associated with environmental contamination (i.e., stigma effects), little attention has been given to the stigma impacts on the local community as a whole. In addition, most estimates of stigma damages have been performed within a community, using distance from contamination or comparing contamination and non contamination areas in the community. In this article we determine stigma damages by analyzing property values in comparable communities and develop the rationale for estimating the community impact associated with environmental contamination that extends beyond the impact on individual property owners. These impacts were estimated for the environmental contamination from zinc smelting in the municipality of Blackwell, Oklahoma. The impacts were measured in terms of lost ad valorem tax revenue using hedonic pricing and average treatment effects.environmental damages, environmental contamination, Environmental Economics and Policy, Q51,

Estimating Government Policy Preferences to Predict New Firm Formation

Entrepreneurship, Entrepreneurial Climate, Subsistance, Discretionary Spending, Community/Rural/Urban Development, Public Economics,

Adoption, Spatial Patterns, and Behavioral Mechanisms in California Turf Removal Rebate Programs

In January of 2014 the Metropolitan Water District of Southern California implemented a $450 million-dollar regional turf removal rebate program which provided homeowners with a cash rebate for every square foot of natural turf removed from their yard and replaced with a program approved alternative. This dissertation is divided into three distinct papers that analyze the role that non-price mechanisms such as peer effects, social norms, personal norms, and household characteristics play in the household decision to participate in this program. The first paper uses a multilevel survival model framework to explore spatial patterns, drivers of participation, and the presence of peer effects. Results show that home ownership, length of time in home, and peer effects all influence the time to participation in the program. The second paper uses a survey tool and a structural equation model to test the applicability of the Theory of Planned Behavior and Value Belief Norm Theory in program participation. The survey was deployed in April of 2018 and had 108 respondents. Results suggest that environmental beliefs and attitudes did not influence participation in the program, while opinions of drought tolerant versus natural turf lawns do. The final paper applies survey methodology and a contingent valuation framework to analyze sensitivity in the household willingness to accept a rebate to participate in the program. Water conservation beliefs and homeowner views over a drought tolerant lawn were both shown reduce the rebate amount required for participation in the program

SOCIAL NETWORKS, SOCIAL CAPITAL AND COMMUNITY ECONOMIC GROWTH

We assess empirically whether social capital affects economic growth in selected United States communities. Social network measures, computed from survey data, are used as proxies for social capital. These measures are used in a conditional convergence growth model to explain the variation of per capita income in the communities.Community/Rural/Urban Development,

Impact of Institutional Support for Research and Development at an R1 University

This study utilizes a correlational research design to identify the relationship, if any, between institutional and external support of research and development (R&D) at an R1 University Carnegie Classification of Institutions of Higher Education R1: Very High Research Activity Doctoral University in the southeastern United States of America. Initial analyses of institutional and external R&D expenditures as reported in the National Science Foundation (NSF) Higher Education Research and Development (HERD) Survey from 2015 through 2020 did not identify any relationships between institutionally and externally funded R&D expenditures. Additionally, initial regressions were directionally split with positive correlations in 14 fields and subfields and negative correlations in 16 fields and subfields

Does Broadband Access Impact Population Growth in Rural America?

Population growth, Broadband, Spatial econometric, Average treatment effects, Community/Rural/Urban Development,