Measuring Motivation Orientation and School Readiness in Children Served by Head Start

Currently, the most widely used direct assessment of motivation orientation for preschoolers has little to no research on its reliability and validity. This study examined the test–retest reliability and concurrent and predictive validity of this direct assessment. Results highlight potential limitations of this measure in capturing motivation orientation in preschoolers from low-income families

Economic instability and aggregate investment

Recent literature suggests that because investment expenditures are irreversible and can be delayed, they may be highly sensitive to uncertainty. The authors briefly summarize the theory, stressing its empirical implications. Then, using cross-section and time-series data for a set of developing and industrial countries, they explore the empirical relevance of irreversibility and uncertainty to aggregate investment. They find that: (a) the volatility of the marginal profitability of capital (a summary measure of uncertainty) affects investment as the theory suggests, but the effect is moderate, and greatest for developing countries; (b)this volatility has little correlation with indices of political instability used in recent studies of growth; (c) inflation is highly correlated with this volatility and is a robust determinant of investment and the marginal profitability ofcapital. The volatility of the real exchange rate also has an independent contribution in explaining investment; and (d) the relationship between inflation and investment is nonlinear, and different thresholds of inflation, where the relationship with investment becomes stronger, were detected for a group of high-inflation countries in Latin America and low-inflation economies in the Organization for Economic Cooperation and Development (OECD).Economic Theory&Research,Environmental Economics&Policies,International Terrorism&Counterterrorism,Banks&Banking Reform,ICT Policy and Strategies

Some lower bounds on sparse outer approximations of polytopes

Motivated by the need to better understand the properties of sparse cutting-planes used in mixed integer programming solvers, the paper [2] studied the idealized problem of how well a polytope is approximated by the use of sparse valid inequalities. As an extension to this work, we study the following less idealized questions in this paper: (1) Are there integer programs, such that sparse inequalities do not approximate the integer hull well even when added to a linear programming relaxation? (2) Are there polytopes, where the quality of approximation by sparse inequalities cannot be significantly improved by adding a budgeted number of arbitrary (possibly dense) valid inequalities? (3) Are there polytopes that are difficult to approximate under every rotation? (4) Are there polytopes that are difficult to approximate in all directions using sparse inequalities? We answer each of the above questions in the positive

Effects of fluid inertia and turbulence on force coefficients for squeeze film dampers

The effects of fluid inertia and turbulence on the force coefficients of squeeze film dampers are investigated analytically. Both the convective and the temporal terms are included in the analysis of inertia effects. The analysis of turbulence is based on friction coefficients currently found in the literature for Poiseuille flow. The effect of fluid inertia on the magnitude of the radial direct inertia coefficient (i.e., to produce an apparent added mass at small eccentricity ratios, due to the temporal terms) is found to be completely reversed at large eccentricity ratios. The reversal is due entirely to the inclusion of the convective inertia terms in the analysis. Turbulence is found to produce a large effect on the direct damping coefficient at high eccentricity ratios. For the long or sealed squeeze film damper at high eccentricity ratios, the damping prediction with turbulence included is an order of magnitude higher than the laminar solution

PPM/NAR 8.4-GHz noise temperature statistics for DSN 64-meter antennas, 1982-1984

From August 1982 through November 1984, X-band downlink (8.4-GHz) system noise temperature measurements were made on the DSN 64-m antennas during tracking periods. Statistics of these noise temperature values are needed by the DSN and by spacecraft mission planners to assess antenna, receiving, and telemetry system needs, present performance, and future performance. These measurements were made using the DSN Mark III precision power monitor noise-adding radiometers located at each station. It is found that for DSS 43 and DSS 63, at the 90% cumulative distribution level, equivalent zenith noise temperature values fall between those presented in the earlier (1977) and present (1983) versions of DSN/Flight Project design documents. Noise temperatures measured for DSS 14 (Goldstone) are higher than those given in existing design documents and this disagreement will be investigated as a diagnostic of possible PPM or receiving system performance problems

Highly dynamically evolved intermediate-age open clusters

We present a comprehensive UBVRI and Washington CT1T2 photometric analysis of seven catalogued open clusters, namely: Ruprecht 3, 9, 37, 74, 150, ESO 324-15 and 436-2. The multiband photometric data sets in combination with 2MASS photometry and Gaia astrometry for the brighter stars were used to estimate their structural parameters and fundamental astrophysical properties.We found that Ruprecht 3 and ESO 436-2 do not show self-consistent evidence of being physical systems. The remained studied objects are open clusters of intermediate age (9.0 ≤ log(t yr-1) ≤ 9.6), of relatively small size (rcls ~ 0.4-1.3 pc) and placed between 0.6 and 2.9 kpc from the Sun.We analysed the relationships between core, half-mass, tidal and Jacoby radii as well as half-mass relaxation times to conclude that the studied clusters are in an evolved dynamical stage. The total cluster masses obtained by summing those of the observed cluster stars resulted to be ~10-15 per cent of the masses of open clusters of similar age located closer than 2 kpc from the Sun. We found that cluster stars occupy volumes as large as those for tidally filled clusters.Fil: Piatti, Andres Eduardo. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Dias, Wilton S.. Universidade Federal de Itajuba; BrasilFil: Sampedro, Laura M.. Instituto de Astrofísica de Andalucía; España. Universidade de Sao Paulo; Brasi

Application of a Fractional Order Integral Resonant Control to increase the achievable bandwidth of a nanopositioner

The congress program will essentially include papers selected on the highest standard by the IPC, according to the IFAC guidelines www.ifac-control.org/publications/Publications-requirements-1.4.pdf, and published in open access in partnership with Elsevier in the IFAC-PapersOnline series, hosted on the ScienceDirect platform www.sciencedirect.com/science/journal/24058963. Survey papers overviewing a research topic are also most welcome. Contributed papers will have usual 6 pages length limitation. 12 pages limitation will apply to survey papers.Publisher PD

The Current Status of Lawyer Professionals: Some Implications for Legal Education

Based on the third lecture of Prof. Watson\u27s three-part Issac Ray Awards lectures. Some Psychological Forces in the Ebb and Flow of Professional Status: Implications for Training and Regulation, delivered at Boalt Hall U of C (Berkleley), Feb. 13-15, 1979