17,692 research outputs found

    Insight into Resonant Activation in Discrete Systems

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    The resonant activation phenomenon (RAP) in a discrete system is studied using the master equation formalism. We show that the RAP corresponds to a non-monotonic behavior of the frequency dependent first passage time probability density function (pdf). An analytical expression for the resonant frequency is introduced, which, together with numerical results, helps understand the RAP behavior in the space spanned by the transition rates for the case of reflecting and absorbing boundary conditions. The limited range of system parameters for which the RAP occurs is discussed. We show that a minimum and a maximum in the mean first passage time (MFPT) can be obtained when both boundaries are absorbing. Relationships to some biological systems are suggested.Comment: 5 pages, 5 figures, Phys. Rev. E., in pres

    Multi-objective evolutionary–fuzzy augmented flight control for an F16 aircraft

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    In this article, the multi-objective design of a fuzzy logic augmented flight controller for a high performance fighter jet (the Lockheed-Martin F16) is described. A fuzzy logic controller is designed and its membership functions tuned by genetic algorithms in order to design a roll, pitch, and yaw flight controller with enhanced manoeuverability which still retains safety critical operation when combined with a standard inner-loop stabilizing controller. The controller is assessed in terms of pilot effort and thus reduction of pilot fatigue. The controller is incorporated into a six degree of freedom motion base real-time flight simulator, and flight tested by a qualified pilot instructor

    The synthesis of 15 mu infrared horizon radiance profiles from meteorological data inputs

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    Computational computer program for modeling infrared horizon radiance profile using pressure and temperature profile input

    Letting Go of Self: The Creation of the Nonattachment to Self Scale

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    The Buddhist notion of nonattachment relates to an engagement with experience with flexibility and without fixation on achieving specified outcomes. The present study sought to define, create and validate a new measure of nonattachment as it applies to notions of the self. A new construct of “nonattachment to self” (NTS) was developed, defined the absence of fixation on self-related concepts, thoughts and feelings, and a capacity to flexibly interact with these concepts, thoughts and feelings without trying to control them. Two studies were conducted in the development of the new scale. With expert consultation, study 1 (n = 445) established a single factor, internally consistent 7-item scale via exploratory factor analysis. Study 2 (n = 388, n = 338) confirmed the factor structure of the new 7-item scale using confirmatory factor analyses. Study 2 also found the new scale to be internally consistent, with evidence supporting its test-retest reliability, criterion, and construct validity. Nonattachment to self-emerged as a unique way of relating to the self, distinct from general nonattachment, that aligned with higher levels of well-being and adaptive functioning

    The outcome of domiciliary medication reviews and their impact: a systematic review

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    OBJECTIVES: Medication reviews in the domiciliary setting are becoming more prevalent internationally. Understanding the benefits of these reviews is essential to ensuring quality healthcare services. To date there has not been a systematic evaluation of the outcomes of these services and their impact on patients. A systematic review of the literature was undertaken with a view to understanding the impact of medication reviews in this setting. Controlled and uncontrolled studies were included. Outcomes were categorised according to the ECHO model. A narrative synthesis was developed. KEY FINDINGS: Nineteen out of 31 papers included demonstrated an improvement in outcome. Clinical outcomes were the most commonly measured and humanistic outcomes the least commonly measured. Domiciliary medication reviews (DMRs) services are presented as providing benefit. However, it is difficult to quantify the impact of services from the published outcomes. SUMMARY: Future work should focus on demonstrating the meaningful changes to patients that DMRs have enabled

    Inversion of the Diffraction Pattern from an Inhomogeneously Strained Crystal using an Iterative Algorithm

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    The displacement field in highly non uniformly strained crystals is obtained by addition of constraints to an iterative phase retrieval algorithm. These constraints include direct space density uniformity and also constraints to the sign and derivatives of the different components of the displacement field. This algorithm is applied to an experimental reciprocal space map measured using high resolution X-ray diffraction from an array of silicon lines and the obtained component of the displacement field is in very good agreement with the one calculated using a finite element model.Comment: 5 pages, 4 figure

    Simultaneous loss and excitation of projectile electrons in relativistic collisions of U90+^{90+}(1s2^2) ions with atoms

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    We study relativistic collisions between helium-like uranium ions initially in the ground state and atoms in which, in a single collision event, one of the electrons of the ion is emitted and the other is transferred into an excited state of the residual hydrogen-like ion. We consider this two-electron process at not very high impact energies, where the action of the atom on the electrons of the ion can be well approximated as occurring solely due to the interaction with the nucleus of the atom and, hence, the process can be regarded as a four-body problem. Using the independent electron model we show that a very substantial improvement in the calculated cross sections is obtained if, instead of the first order approximation, the relativistic symmetric eikonal and continuum-distorted-wave-eikonal-initial-state models are employed to describe the single-electron probabilities for the excitation and loss, respectively.Comment: 12 pages, 2 figures, submitted to J.Phys.

    Extraction of mycelial protein: some specific comparisons

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    Extraction of mycelial protei
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