13 research outputs found

    Analyzing Free Vibration of a Cantilever Microbeam Submerged in Fluid with Free Boundary Approach

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    This paper aims to present a detailed analysis of the free vibration of a cantilever microbeam submerged in an incompressible and frictionless fluid cavity with free boundary condition approach. In other words, in addition to the kinematic compatibility on the boundary between microbeam and its surrounding fluid, equations of the potential functions are modeled assuming the free boundaries. Galerkin’s method is used for simulations. The results of the proposed model are validated by comparing with the early analytical and numerical studies of pertinent literature. Finally, it is inferred that by involving the free boundary conditions, which is closer to the physical reality, the natural frequencies of the system have instability, especially in higher modes. In addition, the values obtained for natural frequencies are smaller than what were calculated by fixed bounary approach

    Recruitment of young women to a trial of chlamydia screening – as easy as it sounds?

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    BACKGROUND: Recruiting to trials is complex and difficult. The Prevention of Pelvic Infection (POPI) trial aims to see if screening women for chlamydia and treating those found to be infected reduces the incidence of pelvic inflammatory disease in the following twelve months. It focuses on young, sexually active, multiethnic, mainly inner city, female students. The main aim of this paper is to describe our recruitment methods. Secondary aims in two small subgroups, are to compare characteristics of women recruited with those not recruited, and to explore participants' understanding of when their samples would be tested for chlamydia. METHODS: Women students attending lectures or in common rooms at 22 universities and further education colleges were recruited by female research assistants working in pairs. Participants were asked to complete a questionnaire on sexual health and to provide self-taken vaginal swabs. In addition, during 3 recruitment sessions, a female medical student asked non-participants to complete a brief anonymous questionnaire on reasons for not taking part. Finally another female medical student contacted 40 consecutive participants within a month of recruitment and asked if they understood that their samples might not be tested for a year. RESULTS: With enormous effort over 2 years we recruited 2526 women. A survey of 61 non-responders showed only 18 (30%) were eligible to take part (age <28, been sexually active and not been tested for chlamydia in the past 3 months). Eligible non-responders were of similar age to the 35 responders in the same recruitment sessions, but more likely to be from ethnic minority groups (67% 12/18 versus 29% 10/35 p < 0.01). Email and telephone contact with 35/40 (88%) of consecutive participants showed only two (6%) did not understand that their specimen might not be tested for chlamydia for a year. Thirty participants (85%) could name one or more possible consequences of untreated chlamydia infection. CONCLUSION: As in other studies, a key to attaining recruitment targets was the enthusiasm of the research team. Minority ethnic groups were probably under-represented, but understanding of participants was good

    Parts of Me : Identity-Relevance Moderates Self-Prioritization

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    Recent research has revealed a pervasive bias for self-relevant information during decision-making, a phenomenon termed the self-prioritization effect. Focusing almost exclusively on between-target (e.g., self vs. friend) differences in task performance, however, this work has overlooked the influence stimulus factors potentially exert during decisional processing. Accordingly, based on pertinent socialpsychological theorizing (i.e., Identity-Based Motivation Theory), here we explored the possibility that self-prioritization is sensitive to the identity-based relevance of stimuli. The results of three experiments supported this hypothesis. In a perceptual-matching task, stimulus enhancement was greatest when geometric shapes were associated with identity-related information that was important (vs. unimportant) to participants. In addition, hierarchical drift-diffusion modeling revealed this effect was underpinned by differences in the efficiency of visual processing. Specifically, evidence was extracted more rapidly from stimuli paired with consequential compared to inconsequential identityrelated components. These findings demonstrate how identity-relevance moderates self-prioritization

    New Results on Multiple Solutions for Nth-Order Fuzzy Differential Equations under Generalized Differentiability

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    We firstly present a generalized concept of higher-order differentiability for fuzzy functions. Then we interpret Nth-order fuzzy differential equations using this concept. We introduce new definitions of solution to fuzzy differential equations. Some examples are provided for which both the new solutions and the former ones to the fuzzy initial value problems are presented and compared. We present an example of a linear second-order fuzzy differential equation with initial conditions having four different solutions

    A Numerical Method for Fuzzy Differential Equations and Hybrid Fuzzy Differential Equations

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    Numerical algorithms for solving first-order fuzzy differential equations and hybrid fuzzy differential equations have been investigated. Sufficient conditions for stability and convergence of the proposed algorithms are given, and their applicability is illustrated with some examples

    NEWTON-PRODUCT INTEGRATION FOR A TWO-PHASE STEFAN PROBLEM WITH KINETICS Communicated by Mohammad Asadzadeh

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    Abstract. We reduce the two phase Stefan problem with kinetic to a system of nonlinear Volterra integral equations of second kind and apply Newton&apos;s method to linearize it. We provide the product integration solution of the linear form. Sufficient conditions for convergence of the numerical method are given and their applicability is illustrated with an example
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