4,508 research outputs found
Computer program for numerical analysis of stiffened shells of revolution
Programs, using Love-Reissner first-order shell theory, can analyze orthotropic thin shells of revolution subjected to unsymmetric distributed loading or concentrated line loads and thermal strains. They can perform stability or vibration analysis of thin shells of revolution subjected to axisymmetric distributed loading or concentrated line loads and thermal strains
Initial Results of a Silicon Sensor Irradiation Study for ILC Extreme Forward Calorimetry
Detectors proposed for the International Linear Collider (ILC) incorporate a
tungsten sampling calorimeter (`BeamCal') intended to reconstruct showers of
electrons, positrons and photons that emerge from the interaction point of the
collider with angles between 5 and 50 milliradians. For the innermost radius of
this calorimeter, radiation doses at shower-max are expected to reach 100 MRad
per year, primarily due to minimum-ionizing electrons and positrons that arise
in the induced electromagnetic showers of e+e- `beamstrahlung' pairs produced
in the ILC beam-beam interaction. However, radiation damage to calorimeter
sensors may be dominated by hadrons induced by nuclear interactions of shower
photons, which are much more likely to contribute to the non-ionizing energy
loss that has been observed to damage sensors exposed to hadronic radiation. We
report here on the results of SLAC Experiment T-506, for which several
different types of silicon diode sensors were exposed to doses of radiation
induced by showering electrons of energy 3.5-10.6 GeV. By embedding the sensor
under irradiation within a tungsten radiator, the exposure incorporated
hadronic species that would potentially contribute to the degradation of a
sensor mounted in a precision sampling calorimeter. Depending on sensor
technology, efficient charge collection was observed for doses as large as 220
MRad.Comment: Talk presented at the International Workshop on Future Linear
Colliders (LCWS13), Tokyo, Japan, 11-15 November 201
Extensible Authentication Protocol Method for 3 rd Generation Authentication
This memo provides information for the Internet community. It does not specify an Internet standard of any kind. Distribution of this memo is unlimited. Copyright Notice Copyright (c) 2009 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust’s Legal Provisions Relating to IETF Documents in effect on the date of publication of this documen
Does lateral lift-off occur in static and dynamic activity in a medially spherical total knee arthroplasty? A pulsed-fluoroscopic investigation.
Objectives: The medially spherical GMK Sphere (Medacta International AG, Castel San Pietro, Switzerland) total knee arthroplasty (TKA) was previously shown to accommodate lateral rollback while pivoting around a stable medial compartment, aiming to replicate native knee kinematics in which some coronal laxity, especially laterally, is also present. We assess coronal plane kinematics of the GMK Sphere and explore the occurrence and pattern of articular separation during static and dynamic activities. Methods: Using pulsed fluoroscopy and image matching, the coronal kinematics and articular surface separation of 16 well-functioning TKAs were studied during weight-bearing and non-weight-bearing, static, and dynamic activities. The closest distances between the modelled articular surfaces were examined with respect to knee position, and proportions of joint poses exhibiting separation were computed. Results: Overall, 1717 joint poses were analyzed. At a 1.0 mm detection threshold, 37 instances of surface separation were observed in the lateral compartment and four medially (p < 0.001). Separation was activity-dependent, both laterally and medially (p < 0.001), occurring more commonly during static deep flexion in the lateral compartment, and during static rotation in the medial compartment. Lateral separation occurred more frequently than medial during kneeling (7/14 lateral vs 1/14 medial; p = 0.031) and stepping (20/1022 lateral vs 0/1022 medial; p < 0.001). Separation varied significantly between individuals during dynamic activities. Conclusion: No consistent association between closest distances of the articular surfaces and knee position was found during any activity. Lift-off was infrequent and depended on the activity performed and the individual knee. Lateral separation was consistent with the design rationale. Medial lift-off was rare and mostly in non-weight-bearing activities.Cite this article: S. Key, G. Scott, J.G. Stammers, M. A. R. Freeman†, V. Pinskerova, R. E. Field, J. Skinner, S. A. Banks. Does lateral lift-off occur in static and dynamic activity in a medially spherical total knee arthroplasty? A pulsed-fluoroscopic investigation. Bone Joint Res 2019;8:207-215. DOI: 10.1302/2046-3758.85.BJR-2018-0237.R1
Three-Dimensional Light Bullets in Arrays of Waveguides
We report the first experimental observation of 3D-LBs, excited by
femtosecond pulses in a system featuring quasi-instantaneous cubic nonlinearity
and a periodic, transversally-modulated refractive index. Stringent evidence of
the excitation of LBs is based on time-gated images and spectra which perfectly
match our numerical simulations. Furthermore, we reveal a novel evolution
mechanism forcing the LBs to follow varying dispersion/diffraction conditions,
until they leave their existence range and decay.Comment: 4 pages, 5 figures - Published by the American Physical Societ
Manure and lagoon nutrients from dairies using flush systems
Nine primar,y lagoons and solids storage
basins were sampled on Kansas dairies using
flush systems. These samples were analyzed
for nutrient content of wastewater and sand
manure. The manure moisture content in the
storage basins averaged 81%. The average
totals of nitrogen, phosphate, and potash
were 3450, 1345, and 1420 mg/L, respectively,
for flushing systems. The average
totals of nitrogen, phosphate, and potash in
the lagoon samples were 816, 337, and 1134
mg/L, respectively, for dairies using recycled
water for flushing alleys. These data and
previously reported data indicate that lagoon
effluent and manure removed from basins
must be managed differently between dairies
using flush versus scrape systems
Surface Effects in Magnetic Microtraps
We have investigated Bose-Einstein condensates and ultra cold atoms in the
vicinity of a surface of a magnetic microtrap. The atoms are prepared along
copper conductors at distances to the surface between 300 um and 20 um. In this
range, the lifetime decreases from 20 s to 0.7 s showing a linear dependence on
the distance to the surface. The atoms manifest a weak thermal coupling to the
surface, with measured heating rates remaining below 500 nK/s. In addition, we
observe a periodic fragmentation of the condensate and thermal clouds when the
surface is approached.Comment: 4 pages, 4 figures; v2: corrected references; v3: final versio
New paradoxical games based on Brownian ratchets
Based on Brownian ratchets, a counter-intuitive phenomenon has recently
emerged -- namely, that two losing games can yield, when combined, a
paradoxical tendency to win. A restriction of this phenomenon is that the rules
depend on the current capital of the player. Here we present new games where
all the rules depend only on the history of the game and not on the capital.
This new history-dependent structure significantly increases the parameter
space for which the effect operates.Comment: 4 pages, 3 eps figures, revte
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