7,822 research outputs found
Prediction of Corner Mechanical Properties for Stainless Steels Due to Cold Forming
The results of a study of the degree of workhardening on stainless steel Types 304, 409, 430 and Type 3CR12 corrosion resisting steel due to cold work of forming are presented in this paper. Analytical inelastic stress-strain relationships are established for virgin tensile specimens. An equation for predicting the yield strength of comers are developed
The Lateral Torsional Buckling Strength of Cold-formed Stainless Steel Beams
The findings of an investigation of the lateral torsional buckling strength of cold-formed stainless steel beams are reported in this study. The sections under consideration are cold-formed lipped channel sections spot-welded back to back to form doubly-symmetric lipped I-beams. The beams were fabricated from a modified AISI Type 409 stainless steel, designated Type 3CR12 corrosion resisting steel. The purpose of this study is to compare the experimental lateral torsional buckling strengths of doubly-symmetric beams to the theoretical predictions proposed by the ASCE Specification for the Design of Cold-Formed Stainless Steel Structural Members. It was concluded in this investigation that an acceptable prediction of beam strength may be obtained through the use of the tangent modulus approach adopted in the ASCE stainless steel design specification
Out of Equilibrium Solutions in the -Hamiltonian Mean Field model
Out of equilibrium magnetised solutions of the -Hamiltonian Mean Field
(-HMF) model are build using an ensemble of integrable uncoupled pendula.
Using these solutions we display an out-of equilibrium phase transition using a
specific reduced set of the magnetised solutions
The Lateral Torsional Buckling Strength of Cold-formed Stainless Steel Lipped Channel Beams
The findings of an investigation into the lateral buckling strength of cold-formed singly-symmetric stainless steel beams are reported in this study. The singly-symmetric sections under consideration were lipped channel sections fabricated from a modified AISI stainless steel Type 409 designated 3CR12, a ferritic corrosion resisting steel. The purpose of this study was to compare the experimental strengths of singly-symmetric sections to the theoretical predictions proposed by the new ASCE Specification for the Design of Cold-Formed Stainless Steel Structural Members. It was concluded in this investigation that the tangent modulus approach adopted in the design specification for stainless steels, compared well with the experimental results
Eccentrically Loaded Bolted Connections for Type 304 and 3CR12 Stainless Steel Lipped Channels
In this paper the results of a study on eccentrically loaded bolted connections in lipped channels are presented. The steels chosen for this study are AISI Type 304 and Type 3CR12 stainless steel. It is concluded in this investigation that an acceptable prediction of the strength of eccentrically loaded bolted connections of stainless steel lipped channels may be obtained through the combination between the eccentric loaded equation and the normal bolted connection equations for stainless steel
Burst Strength of Type 304L Stainless Steel Tubes Subjected to Internal Pressure and External Forces
The findings of an investigation concerning the burst strength of cold-formed Type 304L stainless steel tubes subjected to internal pressure and static external forces are reported in this study. The use of cold-formed stainless steel longitudinally welded tube in pressurised processes in industry are limited due to the belief that seamless tubes have superior resistance to internal pressure. The primary objective of this study was to experimentally and theoretically describe the failure criteria for thin-walled longitudinally welded Type 304L stainless steel tubes subjected to internal pressure and static external point loads and torsion loads. Due to the diversity of the pipe manufacturing process, problem areas which were most likely to cause failures were identified. A microscopic study was done of the weld region where failure was expected in order to support the test results. It was found that cold-formed longitudinally welded Type 304L stainless steel tubes could attain very high bursting pressure values and could compete with seamless tubes in this respect. It was also found that the internal pressure was the most important criteria in tube failure and that the effect of static external forces could be neglected to a certain extent
Gravitational diffraction radiation
We show that if the visible universe is a membrane embedded in a
higher-dimensional space, particles in uniform motion radiate gravitational
waves because of spacetime lumpiness. This phenomenon is analogous to the
electromagnetic diffraction radiation of a charge moving near to a metallic
grating. In the gravitational case, the role of the metallic grating is played
by the inhomogeneities of the extra-dimensional space, such as a hidden brane.
We derive a general formula for gravitational diffraction radiation and apply
it to a higher-dimensional scenario with flat compact extra dimensions.
Gravitational diffraction radiation may carry away a significant portion of the
particle's initial energy. This allows to set stringent limits on the scale of
brane perturbations. Physical effects of gravitational diffraction radiation
are briefly discussed.Comment: 5 pages, 2 figures, RevTeX4. v2: References added. Version to appear
in Phys. Rev.
A single-photon sampling architecture for solid-state imaging
Advances in solid-state technology have enabled the development of silicon
photomultiplier sensor arrays capable of sensing individual photons. Combined
with high-frequency time-to-digital converters (TDCs), this technology opens up
the prospect of sensors capable of recording with high accuracy both the time
and location of each detected photon. Such a capability could lead to
significant improvements in imaging accuracy, especially for applications
operating with low photon fluxes such as LiDAR and positron emission
tomography.
The demands placed on on-chip readout circuitry imposes stringent trade-offs
between fill factor and spatio-temporal resolution, causing many contemporary
designs to severely underutilize the technology's full potential. Concentrating
on the low photon flux setting, this paper leverages results from group testing
and proposes an architecture for a highly efficient readout of pixels using
only a small number of TDCs, thereby also reducing both cost and power
consumption. The design relies on a multiplexing technique based on binary
interconnection matrices. We provide optimized instances of these matrices for
various sensor parameters and give explicit upper and lower bounds on the
number of TDCs required to uniquely decode a given maximum number of
simultaneous photon arrivals.
To illustrate the strength of the proposed architecture, we note a typical
digitization result of a 120x120 photodiode sensor on a 30um x 30um pitch with
a 40ps time resolution and an estimated fill factor of approximately 70%, using
only 161 TDCs. The design guarantees registration and unique recovery of up to
4 simultaneous photon arrivals using a fast decoding algorithm. In a series of
realistic simulations of scintillation events in clinical positron emission
tomography the design was able to recover the spatio-temporal location of 98.6%
of all photons that caused pixel firings.Comment: 24 pages, 3 figures, 5 table
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