221 research outputs found

    A Layered Notch filter for High- Frequency Dynamic Isolation

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    An efficient method of isolation from high-frequency vibrations i

    The evaluation of (social-)psychological comfort in clothing, a possible approach

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    This paper presents the first results of a PhD research on psychological comfort of clothing. In order to understand and conceptualize the psychological aspects of clothing comfort, a variation of the Delphi Method was used to seek opinions from experts. This method was chosen because of its consensus-building features. The results were obtained from a qualitative text analysis, conducted over the experts’ responses to the first round of questions. The analytic process shed some light on the formation of the psychological comfort concept as well as the potential attributes to be evaluated when assessing this comfort dimension.This work is supported by FEDER funds through the Competitivity Factors Operational Programme - COMPETE and by national funds through FCT – Foundation for Science and Technology within the scope of the project POCI-01-0145-FEDER-007136. The first author would also like to gratefully acknowledge the support from the Araucaria Foundation of Paraná State and the Federal University of Technology, specially, the Fashion Design Department and the Office of Research and Graduate Studies.info:eu-repo/semantics/publishedVersio

    Carbon-Rich Mira Variables: Kinematics and Absolute Magnitudes

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    The kinematics of galactic C-Miras are discussed on the basis of the bolometric magnitudes and radial velocities of Papers I and II of this series. Differential galactic rotation is used to derive a zero-point for the bolometric period-luminosity relation which is in satisfactory agreement with that inferred from the LMC C-Miras. We find for the galactic Miras, Mbol = -2.54logP + 2.06 (+/- 0.24), where the slope is taken from the LMC. The mean velocity dispersion, together with the data of Nordstroem et al. and the Padova models, leads to a mean age for our sample of C-Miras of 1.8 +/- 0.4 Gyr and a mean initial mass of 1.8 +/-0.2 solar masses. Evidence for a variation of velocity dispersion with period is found, indicating a dependence of period on age and initial mass, the longer period stars being younger. We discuss the relation between the O- and C-Miras and also their relative numbers in different systems.Comment: 8 pages, 2 figures, accepted for publication in MNRA

    Model Independent Predictions of Big Bang Nucleosynthesis from \he4 and \li7: Consistency and Implications

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    We examine in detail how BBN theory is constrained, and what predictions it can make, when using only the most model-independent observational constraints. We avoid the uncertainties and model-dependencies that necessarily arise when solar neighborhood D and \he3 abundances are used to infer primordial D and \he3 via chemical and stellar evolution models. Instead, we use \he4 and \li7, thoroughly examining the effects of possible systematic errors in each. Via a likelihood analysis, we find near perfect agreement between BBN theory and the most model-independent data. Given this agreement, we then {\it assume} the correctness of BBN to set limits on the single parameter of standard BBN, the baryon-to-photon ratio, and to predict the primordial D and \he3 abundances. We also repeat our analysis including recent measurements of D/H from quasar absorption systems and find that the near perfect agreement between theory and observation of the three isotopes, D, \he4 and \li7 is maintained. These results have strong implications for the chemical and stellar evolution of the light elements, in particular for \he3. In addition, our results (especially if the D/H measurements are confirmed) have implications for the stellar depletion of \li7. Finally, we set limits on the number \nnu\ of neutrino flavors, using an analysis which carefully and systematically includes all available experimental constraints. The value \nnu = 3.0 fits best with BBN and a 95\% CL upper limit of \nnu \la 4 is established.Comment: 28 pages, latex, 10 ps figure

    Solar Neutrinos and the Principle of Equivalence

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    We study the proposed solution of the solar neutrino problem which requires a flavor nondiagonal coupling of neutrinos to gravity. We adopt a phenomenological point of view and investigate the consequences of the hypothesis that the neutrino weak interaction eigenstates are linear combinations of the gravitational eigenstates which have slightly different couplings to gravity, f1Gf_1G and f2Gf_2G, ∣f1−f2∣<<1|f_1-f_2| << 1, corresponding to a difference in red-shift between electron and muon neutrinos, Δz/(1+z)âˆŒâˆŁf1−f2∣\Delta z/(1+z) \sim |f_1 - f_2|. We perform a χ2\chi^2 analysis of the latest available solar neutrino data and obtain the allowed regions in the space of the relevant parameters. The existing data rule out most of the parameter space which can be probed in solar neutrino experiments, allowing only ∣f1−f2âˆŁâˆŒ3×10−14|f_1 - f_2| \sim 3 \times 10^{-14} for small values of the mixing angle (2×10−3≀sin⁥2(2ΞG)≀10−22 \times 10^{-3} \le \sin^2(2\theta_G) \le 10^{-2}) and 10−16∌<∣f1−f2âˆŁâˆŒ<10−1510^{-16} \stackrel{<}{\sim} |f_1 - f_2| \stackrel{<}{\sim}10^{-15} for large mixing (0.6≀sin⁥2(2ΞG)≀0.90.6 \le \sin^2(2\theta_G) \le 0.9). Measurements of the 8B^8{\rm B}-neutrino energy spectrum in the SNO and Super-Kamiokande experiments will provide stronger constraints independent of all considerations related to solar models. We show that these measurements will be able to exclude part of the allowed region as well as to distinguish between conventional oscillations and oscillations due to the violation of the equivalence principle.Comment: 20 pages + 4 figures, IASSNS-AST 94/5

    A decade of theory as reflected in Psychological Science (2009–2019)

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    The dominant belief is that science progresses by testing theories and moving towards theoretical consensus. While it’s implicitly assumed that psychology operates in this manner, critical discussions claim that the field suffers from a lack of cumulative theory. To examine this paradox, we analysed research published in Psychological Science from 2009–2019 (N = 2,225). We found mention of 359 theories in-text, most were referred to only once. Only 53.66% of all manuscripts included the word theory, and only 15.33% explicitly claimed to test predictions derived from theories. We interpret this to suggest that the majority of research published in this flagship journal is not driven by theory, nor can it be contributing to cumulative theory building. These data provide insight into the kinds of research psychologists are conducting and raises questions about the role of theory in the psychological sciences

    How Well Do We (and Will We) Know Solar Neutrino Fluxes and Oscillation Parameters?

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    Assuming neutrino oscillations occur, the pp electron neutrino flux is uncertain by at least a factor of two, the 8B{\rm ^8B} flux by a factor of five, and the 7Be{\rm ^7Be} flux by a factor of forty-five. Calculations of the expected results of future solar neutrino experiments (SuperKamiokande, SNO, BOREXINO, ICARUS, HELLAZ, and HERON) are used to illustrate the extent to which these experiments will restrict the range of the allowed neutrino mixing parameters. We present an improved formulation of the ``luminosity constraint'' and show that at 95\% confidence limit this constraint establishes the best available limits on the rate of creation of pp neutrinos in the solar interior and provides the best upper limit to the 7Be{\rm ^7Be} neutrino flux.Comment: 37 pages, uuencoded Z-compressed postscript file (with figures); Submitted to Physical Review

    Neutrino masses: From fantasy to facts

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    Theory suggests the existence of neutrino masses, but little more. Facts are coming close to reveal our fantasy: solar and atmospheric neutrino data strongly indicate the need for neutrino conversions, while LSND provides an intriguing hint. The simplest ways to reconcile these data in terms of neutrino oscillations invoke a light sterile neutrino in addition to the three active ones. Out of the four neutrinos, two are maximally-mixed and lie at the LSND scale, while the others are at the solar mass scale. These schemes can be distinguished at neutral-current-sensitive solar & atmospheric neutrino experiments. I discuss the simplest theoretical scenarios, where the lightness of the sterile neutrino, the nearly maximal atmospheric neutrino mixing, and the generation of Δm2⊙\Delta {m^2}_\odot & Δm2atm\Delta {m^2}_{atm} all follow naturally from the assumed lepton-number symmetry and its breaking. Although the most likely interpretation of the present data is in terms of neutrino-mass-induced oscillations, one still has room for alternative explanations, such as flavour changing neutrino interactions, with no need for neutrino mass or mixing. Such flavour violating transitions arise in theories with strictly massless neutrinos, and may lead to other sizeable flavour non-conservation effects, such as Ό→e+Îł\mu \to e + \gamma, Ό−e\mu-e conversion in nuclei, unaccompanied by neutrino-less double beta decay.Comment: 33 pages, latex, 16 figures. Invited Talk at Ioannina Conference, Symmetries in Intermediate High Energy Physics and its Applications, Oct. 1998, to be published by Springer Tracts in Modern Physics. Festschrift in Honour of John Vergados' 60th Birthda

    Making sense of leadership development: Developing a community of education leaders

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    In education literature there is a distinct lack of scholarly work on issues of leadership other than on functional leadership at lower levels or high-level individual leadership activity which dominates existing studies. This empirical research is based on the result of a merger of education providers within the North East of England. A crucial aspiration of the newly merged organisation was to provide an overarching innovative leadership structure to facilitate integrated leadership. The specific focus of this article is participants of a bespoke postgraduate learning intervention. The authors apply sense-making theory to identify how student-leaders undertaking a leadership development intervention developed to become a community of education leaders. The reflective accounts of the student-leaders indicated a combined approach of distributed, shared and collaborative leadership. Whilst the study was conducted in the UK, the concepts and ideas are likely to have international application

    Constraints on neutrino oscillation parameters from the measurement of day-night solar neutrino fluxes at Super-Kamiokande

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    A search for day-night variations in the solar neutrino flux resulting from neutrino oscillations has been carried out using the 504 day sample of solar neutrino data obtained at Super-Kamiokande. The absence of a significant day-night variation has set an absolute flux independent exclusion region in the two neutrino oscillation parameter space.Comment: 11 pages, 3 figures, submitted to PRL, single-spacin
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