400 research outputs found
Жанрово-стильові модифікації прози Антона Крушельницького крізь виміри сецесії
Мета нашої статті - інтерпретація прози Антона Крушельницького як визначального представника сецесії через призму жанрово-стильових особливостей
Cervical artery dissection in patients >= 60 years Often painless, few mechanical triggers
Objective: In a cohort of patients diagnosed with cervical artery dissection (CeAD), to determine the proportion of patients aged >= 60 years and compare the frequency of characteristics (presenting symptoms, risk factors, and outcome) in patients aged = 60 years. Methods: We combined data from 3 large cohorts of consecutive patients diagnosed with CeAD (i. e., Cervical Artery Dissection and Ischemic Stroke Patients-Plus consortium). We dichotomized cases into 2 groups, age >= 60 and Results: Among 2,391 patients diagnosed with CeAD, we identified 177 patients (7.4%) aged >= 60 years. In this age group, cervical pain (ORadjusted 0.47 [0.33-0.66]), headache (ORadjusted 0.58 [0.42-0.79]), mechanical trigger events (ORadjusted 0.53 [0.36-0.77]), and migraine (ORadjusted 0.58 [0.39-0.85]) were less frequent than in younger patients. In turn, hypercholesterolemia (ORadjusted 1.52 [1.1-2.10]) and hypertension (ORadjusted 3.08 [2.25-4.22]) were more frequent in older patients. Key differences between age groups were confirmed in secondary analyses. In multivariable, adjusted analyses, favorable outcome (i. e., modified Rankin Scale score 0-2) was less frequent in the older age group (ORadjusted 0.45 [0.25, 0.83]). Conclusion: In our study population of patients diagnosed with CeAD, 1 in 14 was aged >= 60 years. In these patients, pain and mechanical triggers might be missing, rendering the diagnosis more challenging and increasing the risk ofmissed CeAD diagnosis in older patients.Peer reviewe
Design of a Magnetic Bearing
A popular approach to nano-positioning requirements in precision engineering in general and micro-lithography in particular is to subdivide the stage positioning architecture into a coarse positioning module with micrometer accuracy (Long Stroke), onto which a fine positioning module (Short Stroke) is cascaded. The latter is responsible for correcting the residual error of the coarse positioning module to the last nanometers. High accuracy positioning in 6 Degrees Of Freedom put severe constraints on the actuators and/or bearing systems. Actuators are used for generating a varying force being part of a control loop. Bearing systems should generate a force as constant as possible in the bearing direction, but the force perpendicular to that direction should be as low as possible. Actuators could serve as a bearing system, but on the one hand this would require the actuators to be large and thus heavy and on the other hand a substantial amount of heat is continuously dissipated in order to generate the static forces. Such heat generation does not contribute to the positioning performance of the actuators, but significantly affects the thermal stability of the application. The latter implication will be overcome if the bearing system is established by a system with permanent magnets
Positioning system and lithographic projection apparatus
A lithographic apparatus has a positioning system for positioning an object table, said positioning system comprising a planar motor having a stator (10) and a translator (20), one of said stator and said translator comprising a periodic magnet structure (13-15) and the other of said stator and said translator comprising a plurality of energizable coils (21-24). The phase relationship between stator and translator of the planar motor is determined by: energizing a plurality of said energizable coils in turn with an oscillating signal sufficient to cause vibrations of said translator having an amplitude less than the period of said periodic magnet structure; measuring said vibrations of said translator; and determining the phase relationship between said translator and said stator on the basis of said measured vibrations. Alternatively, the relationship between stator and translator is be determined by detecting means detecting distinct optical marks on the periodic magnet array. Control means determine the relationship between said translator and said stator on the basis of detected distinct optical marks
Design tool for a 6-DOF planar motor with moving permanent magnets and standstill coils
This paper describes a fast design tool, which can be used for the rapid modelling, evaluation and optimisation of a moving magnet planar motor. It can be used as an alternative to slow three-dimensional finite element simulations and can calculate forces and torques on the moving platform, which can be positioned in 6-DoF with respect to the stationary part. The force calculations are validated using finite element simulations
Positioning system and lithographic projection apparatus
A lithographic apparatus has a positioning system for positioning an object table, said positioning system comprising a planar motor having a stator (10) and a translator (20), one of said stator and said translator comprising a periodic magnet structure (13-15) and the other of said stator and said translator comprising a plurality of energizable coils (21-24). The phase relationship between stator and translator of the planar motor is determined by: energizing a plurality of said energizable coils in turn with an oscillating signal sufficient to cause vibrations of said translator having an amplitude less than the period of said periodic magnet structure; measuring said vibrations of said translator; and determining the phase relationship between said translator and said stator on the basis of said measured vibrations. Alternatively, the relationship between stator and translator is be determined by detecting means detecting distinct optical marks on the periodic magnet array. Control means determine the relationship between said translator and said stator on the basis of detected distinct optical marks
Direct 3-D method for performance prediction of a linear moving coil actuator with various topologies
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