105,308 research outputs found
The wall of the cave
In this article old and new relations between gauge fields and strings are
discussed. We add new arguments that the Yang Mills theories must be described
by the non-critical strings in the five dimensional curved space. The physical
meaning of the fifth dimension is that of the renormalization scale represented
by the Liouville field. We analyze the meaning of the zigzag symmetry and show
that it is likely to be present if there is a minimal supersymmetry on the
world sheet. We also present the new string backgrounds which may be relevant
for the description of the ordinary bosonic Yang-Mills theories. The article is
written on the occasion of the 40-th anniversary of the IHES.Comment: 18 pages, Late
Thermodynamic property measurements in reflected shock air plasmas at 12,000 - 16,000 K
Reflected shock air plasma thermodynamic properties at 12,000 to 16,000 deg
Three-dimensional coating and rimming flow: a ring of fluid on a rotating horizontal cylinder
The steady three-dimensional flow of a thin, slowly varying ring of Newtonian fluid on either the outside or the inside of a uniformly rotating large horizontal cylinder is investigated. Specifically, we study “full-ring” solutions, corresponding to a ring of continuous, finite and non-zero thickness that extends all the way around the cylinder. In particular, it is found that there is a critical solution corresponding to either a critical load above which no full-ring solution exists (if the rotation speed is prescribed) or a critical rotation speed below which no full-ring solution exists (if the load is prescribed). We describe the behaviour of the critical solution and, in particular, show that the critical flux, the critical load, the critical semi-width and the critical ring profile are all increasing functions of the rotation speed. In the limit of small rotation speed, the critical flux is small and the critical ring is narrow and thin, leading to a small critical load. In the limit of large rotation speed, the critical flux is large and the critical ring is wide on the upper half of the cylinder and thick on the lower half of the cylinder, leading to a large critical load.\ud
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We also describe the behaviour of the non-critical full-ring solution, and, in particular, show that the semi-width and the ring profile are increasing functions of the load but, in general, non-monotonic functions of the rotation speed. In the limit of large rotation speed, the ring approaches a limiting non-uniform shape, whereas in the limit of small load, the ring is narrow and thin with a uniform parabolic profile. Finally, we show that, while for most values of the rotation speed and the load the azimuthal velocity is in the same direction as the rotation of the cylinder, there is a region of parameter space close to the critical solution for sufficiently small rotation speed in which backflow occurs in a small region on the right-hand side of the cylinder
Thermoviscous Coating and Rimming Flow
A comprehensive description is obtained of steady thermoviscous (i.e. with temperature-dependent viscosity) coating and rimming flow on a uniformly rotating horizontal cylinder that is uniformly hotter or colder than the surrounding atmosphere. It is found that, as in the corresponding isothermal problem, there is a critical solution with a corresponding critical load (which depends, in general, on both the Biot number and the thermoviscosity number) above which no ``full-film'' solutions corresponding to a continuous film of fluid covering the entire outside or inside of the cylinder exist. The effect of thermoviscosity on both the critical solution and the full-film solution with a prescribed load is described. In particular, there are no full-film solutions with a prescribed load M for any value of the Biot number when M is greater than or equal to M_{c0} divided by the square root of f for positive thermoviscosity number and when M is greater than M_{c0} for negative thermoviscosity number, where f is a monotonically decreasing function of the thermoviscosity number and M_{c0} = 4.44272 is the critical load in the constant-viscosity case. It is also found that when the prescribed load M is less than 1.50315 there is a narrow region of the Biot number - thermoviscosity number parameter plane in which backflow occurs
System design study for an optimal remote oculometer for use in operational aircraft
System design of optimal remote oculometer for use in operational aircraf
Universal scaling behavior at the upper critical dimension of non-equilibrium continuous phase transitions
In this work we analyze the universal scaling functions and the critical
exponents at the upper critical dimension of a continuous phase transition. The
consideration of the universal scaling behavior yields a decisive check of the
value of the upper critical dimension. We apply our method to a non-equilibrium
continuous phase transition. But focusing on the equation of state of the phase
transition it is easy to extend our analysis to all equilibrium and
non-equilibrium phase transitions observed numerically or experimentally.Comment: 4 pages, 3 figure
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Co-Created Personas: Engaging and Empowering Users with Diverse Needs Within the Design Process
Personas are powerful tools for designing technology and envisioning its usage. They are widely used to imagine archetypal users around whom to orient design work. We have been exploring co-created personas as a technique to use in co-design with users who have diverse needs. Our vision was that this would broaden the demographic and liberate co-designers of their personal relationship with a health condition. This paper reports three studies where we investigated using co-created personas with people who had Parkinson’s disease, dementia or aphasia. Observational data of co-design sessions were collected and analysed. Findings revealed that the co-created personas encouraged users with diverse needs to engage with co-designing. Importantly, they also aforded additional benefts including empowering users within a more accessible design process. Refecting on the outcomes from the diferent user groups, we conclude with a discussion of the potential for co-created personas to be applied more broadly
Is voice therapy an effective treatment for dysphonia? A randomised controlled trial
OBJECTIVES: To assess the overall efficacy of voice therapy for dysphonia. DESIGN: Single blind randomised controlled trial. SETTING: Outpatient clinic in a teaching hospital. Participants: 204 outpatients aged 17-87 with a primary symptom of persistent hoarseness for at least two months. INTERVENTIONS: After baseline assessments, patients were randomised to six weeks of either voice therapy or no treatment. Assessments were repeated at six weeks on the 145 (71%) patients who continued to this stage and at 12-14 weeks on the 133 (65%) patients who completed the study. The assessments at the three time points for the 70 patients who completed treatment and the 63 patients in the group given no treatment were compared. MAIN OUTCOME MEASURES: Ratings of laryngeal features, Buffalo voice profile, amplitude and pitch perturbation, voice profile questionnaire, hospital anxiety and depression scale, clinical interview schedule, SF-36. RESULTS: Voice therapy improved voice quality as assessed by rating by patients (P=0.001) and rating by observer (P<0.001). The treatment effects for these two outcomes were 4.1 (95% confidence interval 1.7 to 6.6) points and 0.82 (0.50 to 1.13) points. Amplitude perturbation showed improvement at six weeks (P=0.005) but not on completion of the study. Patients with dysphonia had appreciable psychological distress and lower quality of life than controls, but voice therapy had no significant impact on either of these variables. CONCLUSION: Voice therapy is effective in improving voice quality as assessed by self rated and observer rated methods
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