654 research outputs found
NNEP: The Navy NASA Engine Program
A computer code capable of simulating almost any conceivable turbine engine is described. This code uses stacked component maps and multiple flowpaths to simulate variable cycle engines with variable component geometry. It is capable of design and off-design (matching) calculations and can optimize free variables such as nozzle areas to minimize specific fuel consumption
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Not All Bad Apples Spoil the Bunch: Order Effects on the Evaluation of Groups
When group members are encountered in a random sequential order, people expect the first (vs. middle or last) member to be more diagnostic of the group. Therefore, they weigh the performance of the first (vs. middle or last) more heavily in their predictions and decisions about the whole group
Computer optimization of reactor-thermoelectric space power systems
A computer simulation and optimization code that has been developed for nuclear space power systems is described. The results of using this code to analyze two reactor-thermoelectric systems are presented
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The First-Member Heuristic: Group Members Labeled “First” Influence Judgment and Treatment of Groups
People often make judgments about a group (e.g., immigrants from a specific country) based on information about a single group member. Seven studies (N = 1,929) tested the hypothesis that people will expect the performance of an arbitrarily ordered group to match that of the group member in the first position of a sequence more closely than that of group members in other positions. This greater perceived diagnosticity of the first member will in turn affect how people treat the group. This pattern of judgment and treatment of groups, labeled the “firstmember heuristic,” generalized across various performance contexts (e.g., gymnastic outine, relay race, job performance), and regardless of whether the focal member performed poorly or well (Studies 1-3). Consistent with the notion that first members are deemed most informative, participants were most likely to turn to the member in the first (vs. other) position to learn about the group (Study 4). Further, through their disproportionate influence on the expected performance of other group members, first members’ performances also influenced participants’ support of policies that would benefit or hurt a group (Study 5) and their likelihood to join a group (Study 6). Finally, perceived group homogeneity moderated the first-member heuristic, such that it attenuated for nonhomogeneous groups (Study 7)
A comparison of computerized MMPI reports of French-English bilingual Canadian students.
Dept. of Psychology. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1973 .F46. Source: Masters Abstracts International, Volume: 40-07, page: . Thesis (M.A.)--University of Windsor (Canada), 1973
A Standard Siren Measurement of the Hubble Constant from GW170817 without the Electromagnetic Counterpart
We perform a statistical standard siren analysis of GW170817. Our analysis does not utilize knowledge of NGC 4993 as the unique host galaxy of the optical counterpart to GW170817. Instead, we consider each galaxy within the GW170817 localization region as a potential host; combining the redshifts from all of the galaxies with the distance estimate from GW170817 provides an estimate of the Hubble constant, H_0. Considering all galaxies brighter than 0.626L*_B as equally likely to host a binary neutron star merger, we find H_0 – 77^(+37)_(-18) km s^(−1) Mpc^(−1) (maximum a posteriori and 68.3% highest density posterior interval; assuming a flat H_0 prior in the range [10, 220] km s^(−1) Mpc^(−1)). We explore the dependence of our results on the thresholds by which galaxies are included in our sample, and we show that weighting the host galaxies by stellar mass or star formation rate provides entirely consistent results with potentially tighter constraints. By applying the method to simulated gravitational-wave events and a realistic galaxy catalog we show that, because of the small localization volume, this statistical standard siren analysis of GW170817 provides an unusually informative (top 10%) constraint. Under optimistic assumptions for galaxy completeness and redshift uncertainty, we find that dark binary neutron star measurements of H_0 will converge as 40%/√(N), where N is the number of sources. While these statistical estimates are inferior to the value from the counterpart standard siren measurement utilizing NGC 4993 as the unique host, H_0 = 76^(+19)_(-13) km s^(−1) Mpc^(−1) (determined from the same publicly available data), our analysis is a proof-of-principle demonstration of the statistical approach first proposed by Bernard Schutz over 30 yr ago
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