1,919 research outputs found

    Structured Transition of Wind Tunnel Operations Skills from Government-to Contractor-Managed

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    In 2004, NASA awarded the Research, Operations, Maintenance, and Engineering (ROME) contract at NASA Langley Research Center to a team led by Jacobs Technology, Inc. A key component of the contract was the transitioning of the five large wind tunnel facilities from NASA managed and NASA or NASA/contractor workforces to fully contractor operated. The contractor would manage daily operations while NASA would continue to develop long-term strategies, make decisions regarding commitment of funds and commitment of facilities, and provide oversight of the contractor's performance. A major challenge would be the transition of knowledge of facility operations and maintenance from the incumbent civil servant workforce to the contractor workforce. While the contract has since been modified multiple times, resulting in a blended NASA/ROME workforce across the facilities, the processes developed and implemented to capture and document facility knowledge from the incumbent subject matter experts, build training and certification programs, and grow individual skills across subject areas and across facilities, are worthy of documentation. This is the purpose of this paper

    Models of risky choice: A state-trace and signed difference analysis

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    Models of risky choice fall into two broad classes; fixed utility models that satisfy the condition of simple scalability and everything else. While it is known that choice behavior can be observed that is inconsistent with all models, this has largely been based on the construction of special cases. We use state-trace analysis and signed difference analysis to test a set of models on a set of ecologically representative risky choices. An advantage of this approach is that there is no requirement to posit a particular form for the error function that links the difference in the utilities of two gambles, A and B, with the probability of choosing A over B. We presented groups of participants with 30 variable gambles (A), each paired with one of four fixed gambles (B). We use state-trace analysis to test the prediction of all fixed utility models that the probability of choosing each A has the same order for all B. The results show that this prediction is not confirmed and a more complex model is required. We then use signed difference analysis to test two more complex models — the random subjective expected utility model based on Decision Field Theory and a fixed utility mixture model. We derive a key prediction from the random subjective expected utility model and show that it is confirmed by the data. In contrast, the data are shown to be inconsistent with the fixed utility mixture model

    Corn substitutes for fattening lambs—Parts I and II

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    Shelled corn is a superior basal grain for fattening lambs in dry lot, in the cornbelt and under the conditions of the experiments reported in this bulletin. This fact stands out clearly in the results of the two years’ work at the Iowa Agricultural Experiment Station in the winters of 1918-19 and 1919-20. Shelled corn proved to be more efficient than either oats or barley when fed alone, this being the case when all factors, such as feed required per hundred pounds gain, feed costs, cost of shipping and margin of profit or loss per lamb, are considered

    GTTC Future of Ground Testing Meta-Analysis of 20 Documents

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    National research, development, test, and evaluation ground testing capabilities in the United States are at risk. There is a lack of vision and consensus on what is and will be needed, contributing to a significant threat that ground test capabilities may not be able to meet the national security and industrial needs of the future. To support future decisions, the AIAA Ground Testing Technical Committees (GTTC) Future of Ground Test (FoGT) Working Group selected and reviewed 20 seminal documents related to the application and direction of ground testing. Each document was reviewed, with the content main points collected and organized into sections in the form of a gap analysis current state, future state, major challenges/gaps, and recommendations. This paper includes key findings and selected commentary by an editing team

    Enzyme activity below the dynamical transition at 220 K

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    Enzyme activity requires the activation of anharmonic motions, such as jumps between potential energy wells. However, in general, the forms and time scales of the functionally important anharmonic dynamics coupled to motion along the reaction coordinate remain to be determined. In particular, the question arises whether the temperature-dependent dynamical transition from harmonic to anharmonic motion in proteins, which has been observed experimentally and using molecular dynamics simulation, involves the activation of motions required for enzyme function. Here we present parallel measurements of the activity and dynamics of a cryosolution of glutamate dehydrogenase as a function of temperature. The dynamical atomic fluctuations faster than ~100 ps were determined using neutron scattering. The results show that the enzyme remains active below the dynamical transition observed at ~220 K, i.e., at temperatures where no anharmonic motion is detected. Furthermore, the activity shows no significant deviation from Arrhenius behavior down to 190 K. The results indicate that the observed transition in the enzyme's dynamics is decoupled from the rate-limiting step along the reaction coordinate

    Do sequential lineups impair underlying discriminability?

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    © 2020, The Author(s). Debate regarding the best way to test and measure eyewitness memory has dominated the eyewitness literature for more than 30 years. We argue that resolution of this debate requires the development and application of appropriate measurement models. In this study we developed models of simultaneous and sequential lineup presentations and used these to compare these procedures in terms of underlying discriminability and response bias, thereby testing a key prediction of diagnostic feature detection theory, that underlying discriminability should be greater for simultaneous than for stopping-rule sequential lineups. We fit the models to the corpus of studies originally described by Palmer and Brewer (2012, Law and Human Behavior, 36(3), 247–255), to data from a new experiment and to eight recent studies comparing simultaneous and sequential lineups. We found that although responses tended to be more conservative for sequential lineups there was little or no difference in underlying discriminability between the two procedures. We discuss the implications of these results for the diagnostic feature detection theory and other kinds of sequential lineups used in current jurisdictions

    Formation of public strategic planning in Ukraine

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    It is sometimes the case that a theory proposes that the population means on two variables should have the same rank order across a set of experimental conditions. This paper presents a test of this hypothesis. The test statistic is based on the coupled monotonic regression algorithm developed by the authors. The significance of the test statistic is determined by comparison to an empirical distribution specific to each case, obtained via non-parametric or semi-parametric bootstrap. We present an analysis of the power and Type I error control of the test based on numerical simulation. Partial order constraints placed on the variables may sometimes be theoretically justified. These constraints are easily incorporated into the computation of the test statistic and are shown to have substantial effects on power. The test can be applied to any form of data, as long as an appropriate statistical model can be specified.free access is valid until January 8, 2016:http://authors.elsevier.com/a/1S3XC53naPWGhFunding agencies: Australian Research Council [0877510, 0878630, 110100751, 130101535]; National Science Foundation [1256959]; Linkoping University</p

    Book Reviews

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    GOVERNMENTAL REORGANIZATIONS: CASES AND COMMENTARY. Edited by Frederick C. Moshe. THE CHANGING LAW OF NATIONS: ESSAYS ON INTERNATIONAL LAW. By Josef L. Kunz. THE BOOM IN GOING BUST: THE GROWING SCANDAL IN PERSONAL BANKRUPTCY. By George Sullivan. INVISIBLE WITNESS: THE USE AND ABUSE OF THE NEW TECHNOLOGY OF CRIME INVESTIGATION. By William W. Turner

    Risk, ambiguity and quantum decision theory

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    In the present article we use the quantum formalism to describe the effects of risk and ambiguity in decision theory. The main idea is that the probabilities in the classic theory of expected utility are estimated probabilities, and thus do not follow the classic laws of probability theory. In particular, we show that it is possible to use consistently the classic expected utility formula, where the probability associated to the events are computed with the equation of quantum interference. Thus we show that the correct utility of a lottery can be simply computed by adding to the classic expected utility a new corrective term, the uncertainty utility, directly connected with the quantum interference term.Comment: 1 figur

    Messenger RNA coding for only the alpha subunit of the rat brain Na channel is sufficient for expression of functional channels in Xenopus oocytes

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    Several cDNA clones coding for the high molecular weight (alpha) subunit of the voltage-sensitive Na channel have been selected by immunoscreening a rat brain cDNA library constructed in the expression vector lambda gt11. As will be reported elsewhere, the amino acid sequence translated from the DNA sequence shows considerable homology to that reported for the Electrophorus electricus electroplax Na channel. Several of the cDNA inserts hybridized with a low-abundance 9-kilobase RNA species from rat brain, muscle, and heart. Sucrose-gradient fractionation of rat brain poly(A) RNA yielded a high molecular weight fraction containing this mRNA, which resulted in functional Na channels when injected into oocytes. This fraction contained undetectable amounts of low molecular weight RNA. The high molecular weight Na channel RNA was selected from rat brain poly(A) RNA by hybridization to a single-strand antisense cDNA clone. Translation of this RNA in Xenopus oocytes resulted in the appearance of tetrodotoxin-sensitive voltage-sensitive Na channels in the oocyte membrane. These results demonstrate that mRNA encoding the alpha subunit of the rat brain Na channel, in the absence of any beta-subunit mRNA, is sufficient for translation to give functional channels in oocytes
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