123 research outputs found

    Real-time fault diagnosis for propulsion systems

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    Current research toward real time fault diagnosis for propulsion systems at NASA-Lewis is described. The research is being applied to both air breathing and rocket propulsion systems. Topics include fault detection methods including neural networks, system modeling, and real time implementations

    Alpha-canonical form representation of the open loop dynamics of the Space Shuttle main engine

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    A parameter and structure estimation technique for multivariable systems is used to obtain a state space representation of open loop dynamics of the space shuttle main engine in alpha-canonical form. The parameterization being used is both minimal and unique. The simplified linear model may be used for fault detection studies and control system design and development

    Identification of space shuttle main engine dynamics

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    System identification techniques are used to represent the dynamic behavior of the Space Shuttle Main Engine. The transfer function matrices of the linearized models of both the closed loop and the open loop system are obtained by using the recursive maximum likelihood method

    Some inequalities in B

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    Let H denote a separable Hilbert space and let B(H) be the space of bounded and linear operators from H to H. We define a subspace Δ(A,B) of B(H), and prove two inequalities between the distance to Δ(A,B) of each operator T in B(H), and the value sup{‖AnTBn−T‖:n=1,2,…}

    Sex differences in mate preferences across 45 countries: A large-scale replication

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    Considerable research has examined human mate preferences across cultures, finding universal sex differences in preferences for attractiveness and resources as well as sources of systematic cultural variation. Two competing perspectives-an evolutionary psychological perspective and a biosocial role perspective-offer alternative explanations for these findings. However, the original data on which each perspective relies are decades old, and the literature is fraught with conflicting methods, analyses, results, and conclusions. Using a new 45-country sample (N = 14,399), we attempted to replicate classic studies and test both the evolutionary and biosocial role perspectives. Support for universal sex differences in preferences remains robust: Men, more than women, prefer attractive, young mates, and women, more than men, prefer older mates with financial prospects. Cross-culturally, both sexes have mates closer to their own ages as gender equality increases. Beyond age of partner, neither pathogen prevalence nor gender equality robustly predicted sex differences or preferences across countries.info:eu-repo/semantics/acceptedVersio

    Highlights of the ERS Lung Science Conference and Sleep and Breathing Conference 2021 and the new ECMC members

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    The Lung Science Conference (LSC) and the Sleep and Breathing Conference (SBC) are two conferences organised by the European Respiratory Society (ERS), the latter held in association with the European Sleep Research Society. This year, the LSC and SBC were both held in a virtual format with the participation of researchers and clinicians from around the world. The participation of Early Career Members (ECMs) was notable in both events: 216 of 363 (60%) delegates attending the LSC were under 40?years old, and 315 of 920 (34%) delegates were ?40?years of age at the SBC. Both conferences included outstanding talks on the most recent advances in respiratory medicine and science, oral/poster communication sessions on novel research, exciting opportunities to network with peers, and much more!This paper provides a brief overview of some of the most remarkable sessions of the LSC and SBC, written by ECMs attending the sessions.We also present the new members of the Early Career Member Committee (ECMC) of the ERS from Assemblies 1, 4, 10, 12 and 13, who were elected in the latest round of ERS elections. Welcome aboard

    Validation of the Short Version (TLS-15) of the Triangular Love Scale (TLS-45) Across 37 Languages

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    Love is a phenomenon that occurs across the world and affects many aspects of human life, including the choice of, and process of bonding with, a romantic partner. Thus, developing a reliable and valid measure of love experiences is crucial. One of the most popular tools to quantify love is Sternberg’s 45-item Triangular Love Scale (TLS-45), which measures three love components: intimacy, passion, and commitment. However, our literature review reveals that most studies (64%) use a broad variety of shortened versions of the TLS-45. Here, aiming to achieve scientific consensus and improve the reliability, comparability, and generalizability of results across studies, we developed a short version of the scale—the TLS-15—comprised of 15 items with 5-point, rather than 9-point, response scales. In Study 1 (N = 7,332), we re-analyzed secondary data from a large-scale multinational study that validated the original TLS-45 to establish whether the scale could be truncated. In Study 2 (N = 307), we provided evidence for the three-factor structure of the TLS-15 and its reliability. Study 3 (N = 413) confirmed convergent validity and test–retest stability of the TLS-15. Study 4 (N = 60,311) presented a large-scale validation across 37 linguistic versions of the TLS-15 on a cross-cultural sample spanning every continent of the globe. The overall results provide support for the reliability, validity, and cross-cultural invariance of the TLS-15, which can be used as a measure of love components—either separately or jointly as a three-factor measure
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