Investigating complex aerodynamic flows with a laser velocimeter

The application of the laser velocimeter in the study of two highly complex aerodynamic flows is discussed. In the first experiment, the laser velocimeter was used with frequency tracking electronics to survey the multiple vortex wake structure behind a model of a large jet transport. The second application is to the study of the induced instantaneous inflow velocities near the blades of a model helicopter rotor; counter-type processing was used in these measurements. In each experiment, the data output channels of these processors were handled in an on-line fashion, including both velocity computations and the plotting of fully reduced data

MEASUREMENTS OF SMALL AMOUNTS OF Hsub2sub 2O IN Dsub2sub 2O BY NEAR-INFRARED ABSORPTION SPECTROSCOPY

The literature on the near-infrared and infrared absorption spectra of liquid H/sub 2/O and D/sub 2/O as well as other literature related to the determination of small amounts of one in the presence of the other was reviewed. Nearinfrared absorption techniques appear to be very convenient, rapid, and almost ideally suited for the determination of H/sub 2/O in the concentration range from 0 to 10% in D/sub 2/O. The absorption spectra of H/sub 2/O, D/sub 2/ O, (HDO), and of mixtures of H/sub 2/O in D/sub 2/O were obtained using a Cary Model l4 PM Recording Spectrophotometer. As expected. the H/sub 2/O was found to undergo very rapid and almost complete exchange to HDO, especially at relatively low H/sub 2/O concentrations. In agreement with some previously reported French and Japanese work, a relatively intense and very useful absorption band for HDO has been found at l.668 mu , and it is used for the determination. By the use of the procedure described. 0.5, 2, 4, and 7 wt.% H/sub 2/O in D/sub 2/O can be determined with respective approximate relative standard deviations of 7, 2, 1, and 0.7% when 1-cm absorption cells are used in conjunction with a pure D/sub 2/O reference liquid. (auth

Time-of-flight Emission Profiles of the Entire Plume Using Fast Imaging During Pulsed Laser Deposition of YBa\u3csub\u3e2\u3c/sub\u3eCu\u3csub\u3e3\u3c/sub\u3eO\u3csub\u3e7−x\u3c/sub\u3e

Emission time-of-flight (TOF) profiles have been obtained using gated imagery to further the process control during the pulsed laser deposition of the high temperature superconductor, YBa2Cu3O7−x⁠. An intensified charge coupled device array was used to obtain a sequence of plume images at 10ns temporal resolution and 0.2mm spatial resolution. Plume imagery is transformed to TOF profiles and pulse-to-pulse variations removed using physically based smoothing techniques. Comparison with non-imaging sensors establishes excellent agreement, with systematic uncertainties in streaming speed and temperatures of less than 15% and 8%, respectively. The resulting streaming speeds of 0.4–1.2×106 cm/s and characteristic temperatures of 20000–200000K are characterized across the full plume. This new imaging TOF technique enables the monitoring of the complete evolution of speed distributions. Indeed, significant deviations from the forward-directed Maxwellian speed distributions are observed

Ballot secrecy concerns and voter mobilization: new experimental evidence about message source, context, and the duration of mobilization effects

Recent research finds that doubts about the integrity of the secret ballot as an institution persist among the American public. We build on this finding by providing novel field experimental evidence about how information about ballot secrecy protections can increase turnout among registered voters who had not previously voted. First, we show that a private group’s mailing designed to address secrecy concerns modestly increased turnout in the highly contested 2012 Wisconsin gubernatorial recall election. Second, we exploit this and an earlier field experiment conducted in Connecticut during the 2010 congressional midterm election season to identify the persistent effects of such messages from both governmental and non-governmental sources. Together, these results provide new evidence about how message source and campaign context affect efforts to mobilize previous non-voters by addressing secrecy concerns, as well as show that attempting to address these beliefs increases long term participation

Self-interest, beliefs, and policy opinions: understanding how economic beliefs affect immigration policy preferences

Research on how economic factors affect attitudes toward immigration often focuses on labor market effects, concluding that, because workers’ skill levels do not predict opposition to low- versus highly skilled immigration, economic self-interest does not shape policy attitudes. We conduct a new survey to measure beliefs about a range of economic, political, and cultural consequences of immigration. When economic self-interest is broadened to include concerns about the fiscal burdens created by immigration, beliefs about these economic effects strongly correlate with immigration attitudes and explain a significant share of the difference in support for highly versus low-skilled immigration. Although cultural factors are important, our results suggest that previous work underestimates the importance of economic self-interest as a source of immigration policy preferences and attitudes more generally

Subtle linguistic cues may not affect voter behavior: new evidence

One of the most important recent developments in social psychology is the discovery of minor interventions that have large and enduring effects on behavior. A leading example of this class of results is Bryan et al. (2011), which shows that administering a set of survey items worded so that subjects think of themselves as voters (noun treatment) rather than as voting (verb treatment) substantially increases political participation (voter turnout) among subjects. We revisit these experiments by replicating and extending their research design in a large-scale field experiment. In contrast to the 11 to 14 percentage point greater turnout among those exposed to the noun rather than verb treatment reported in Bryan et al. (2011), we find no statistically significant difference in turnout between the noun and verb treatments (the point estimate of the difference is approximately zero). Further, when we benchmark these treatments against a standard get-outthe- vote message, we find that both are less effective at increasing turnout than a much shorter basic mobilization message. In sum, in our experiments, we find no evidence that describing a subject as a voter rather than as voting has a positive relative or absolute effect on subject behavior. In our conclusion, we detail how our study differs from Bryan et al. (2011) and discuss how our results might be interpreted

Design, analysis, and testing of a metal matrix composite web/flange intersection

An experimental and analytical program to study the local design details of a typical T-shaped web/flange intersection made from a metal matrix composite is described. Loads creating flange bending were applied to specimens having different designs and boundary conditions. Finite element analyses were conducted on models of the test specimens to predict the structural response. The analyses correctly predict failure load, mode, and location in the fillet material in the intersection region of the web and the flange when specimen quality is good. The test program shows the importance of fabrication quality in the intersection region. The full-scale test program that led to the investigation of this local detail is also described

Reporting guidelines for experimental research: A report from the experimental research section standards committee.

The standards committee of the Experimental Research section was charged with preparing a set of reporting guidelines for experimental research in political science. The committee defined its task as compiling a set of guidelines sufficient to enable the reader or reviewer to follow what the researcher had done and to assess the validity of the conclusions the researcher had drawn. Although the guidelines do request the reporting of some basic statistics, they do not attempt to weigh in on statistical controversies. Rather, they aim for something more modest but nevertheless crucial: to ensure that scholars clearly describe what it is they did at each step in their research and clearly report what their data show. In this paper, we discuss the rationale for reporting guidelines and the process used to formulate the specific guidelines we endorse. The guidelines themselves are included in Appendix 1

Alternating groups and moduli space lifting Invariants

Main Theorem: Spaces of r-branch point 3-cycle covers, degree n or Galois of degree n!/2 have one (resp. two) component(s) if r=n-1 (resp. r\ge n). Improves Fried-Serre on deciding when sphere covers with odd-order branching lift to unramified Spin covers. We produce Hurwitz-Torelli automorphic functions on Hurwitz spaces, and draw Inverse Galois conclusions. Example: Absolute spaces of 3-cycle covers with +1 (resp. -1) lift invariant carry canonical even (resp. odd) theta functions when r is even (resp. odd). For inner spaces the result is independent of r. Another use appears in, http://www.math.uci.edu/~mfried/paplist-mt/twoorbit.html, "Connectedness of families of sphere covers of A_n-Type." This shows the M(odular) T(ower)s for the prime p=2 lying over Hurwitz spaces first studied by, http://www.math.uci.edu/~mfried/othlist-cov/hurwitzLiu-Oss.pdf, Liu and Osserman have 2-cusps. That is sufficient to establish the Main Conjecture: (*) High tower levels are general-type varieties and have no rational points.For infinitely many of those MTs, the tree of cusps contains a subtree -- a spire -- isomorphic to the tree of cusps on a modular curve tower. This makes plausible a version of Serre's O(pen) I(mage) T(heorem) on such MTs. Establishing these modular curve-like properties opens, to MTs, modular curve-like thinking where modular curves have never gone before. A fuller html description of this paper is at http://www.math.uci.edu/~mfried/paplist-cov/hf-can0611591.html .Comment: To appear in the Israel Journal as of 1/5/09; v4 is corrected from proof sheets, but does include some proof simplification in \S