13,760 research outputs found
The "MIND" Scalable PIM Architecture
MIND (Memory, Intelligence, and Network Device) is an advanced parallel computer architecture for high performance computing and scalable embedded processing. It is a
Processor-in-Memory (PIM) architecture integrating both DRAM bit cells and CMOS logic devices on the same silicon die. MIND is multicore with multiple memory/processor nodes on
each chip and supports global shared memory across systems of MIND components. MIND is distinguished from other PIM architectures in that it incorporates mechanisms for efficient support of a global parallel execution model based on the semantics of message-driven multithreaded split-transaction processing. MIND is designed to operate either in conjunction with other conventional microprocessors or in standalone arrays of like devices. It also incorporates mechanisms for fault tolerance, real time execution, and active power management. This paper describes the major elements and operational methods of the MIND
architecture
On-board processing satellite network architecture and control study
The market for telecommunications services needs to be segmented into user classes having similar transmission requirements and hence similar network architectures. Use of the following transmission architecture was considered: satellite switched TDMA; TDMA up, TDM down; scanning (hopping) beam TDMA; FDMA up, TDM down; satellite switched MF/TDMA; and switching Hub earth stations with double hop transmission. A candidate network architecture will be selected that: comprises multiple access subnetworks optimized for each user; interconnects the subnetworks by means of a baseband processor; and optimizes the marriage of interconnection and access techniques. An overall network control architecture will be provided that will serve the needs of the baseband and satellite switched RF interconnected subnetworks. The results of the studies shall be used to identify elements of network architecture and control that require the greatest degree of technology development to realize an operational system. This will be specified in terms of: requirements of the enabling technology; difference from the current available technology; and estimate of the development requirements needed to achieve an operational system. The results obtained for each of these tasks are presented
Local Alignment of the BABAR Silicon Vertex Tracking Detector
The BABAR Silicon Vertex Tracker (SVT) is a five-layer double-sided silicon
detector designed to provide precise measurements of the position and direction
of primary tracks, and to fully reconstruct low-momentum tracks produced in
e+e- collisions at the PEP-II asymmetric collider at Stanford Linear
Accelerator Center. This paper describes the design, implementation,
performance, and validation of the local alignment procedure used to determine
the relative positions and orientations of the 340 SVT wafers. This procedure
uses a tuned mix of in-situ experimental data and complementary lab-bench
measurements to control systematic distortions. Wafer positions and
orientations are determined by minimizing a chisquared computed using these
data for each wafer individually, iterating to account for between-wafer
correlations. A correction for aplanar distortions of the silicon wafers is
measured and applied. The net effect of residual mis-alignments on relevant
physical variables is evaluated in special control samples. The BABAR
data-sample collected between November 1999 and April 2008 is used in the study
of the SVT stability.Comment: 21 pages, 20 figures, 3 tables, submitted to Nucl. Instrum. Meth.
Infrastructure for Detector Research and Development towards the International Linear Collider
The EUDET-project was launched to create an infrastructure for developing and
testing new and advanced detector technologies to be used at a future linear
collider. The aim was to make possible experimentation and analysis of data for
institutes, which otherwise could not be realized due to lack of resources. The
infrastructure comprised an analysis and software network, and instrumentation
infrastructures for tracking detectors as well as for calorimetry.Comment: 54 pages, 48 picture
VIS: the visible imager for Euclid
Euclid-VIS is a large format visible imager for the ESA Euclid space mission
in their Cosmic Vision program, scheduled for launch in 2019. Together with the
near infrared imaging within the NISP instrument it forms the basis of the weak
lensing measurements of Euclid. VIS will image in a single r+i+z band from
550-900 nm over a field of view of ~0.5 deg2. By combining 4 exposures with a
total of 2240 sec, VIS will reach to V=24.5 (10{\sigma}) for sources with
extent ~0.3 arcsec. The image sampling is 0.1 arcsec. VIS will provide deep
imaging with a tightly controlled and stable point spread function (PSF) over a
wide survey area of 15000 deg2 to measure the cosmic shear from nearly 1.5
billion galaxies to high levels of accuracy, from which the cosmological
parameters will be measured. In addition, VIS will also provide a legacy
imaging dataset with an unprecedented combination of spatial resolution, depth
and area covering most of the extra-Galactic sky. Here we will present the
results of the study carried out by the Euclid Consortium during the Euclid
Definition phase.Comment: 10 pages, 6 figure
MEMS micro-contact printing engines
This thesis investigates micro-contact printing (µCP) engines using micro-electro-mechanical
systems (MEMS). Such engines are self-contained and do not require further optical
alignment and precision manipulation equipment. Hence they provide a low-cost and
accessible method of multilevel surface patterning with sub-micron resolution. Applications
include the field of biotechnology where the placement of biological ligands at well
controlled locations on substrates is often required for biological assays, cell studies and
manipulation, or for the fabrication of biosensors.
A miniaturised silicon µCP engine is designed and fabricated using a wafer-scale MEMS
fabrication process and single level and bi-level µCP are successfully demonstrated. The
performance of the engine is fully characterised and two actuation modes, mechanical and
electrostatic, are investigated. In addition, a novel method of integrating the stamp material
into the MEMS process flow by spray coating is reported.
A second µCP engine formed by wafer-scale replica moulding of a polymer is developed to
further drive down cost and complexity. This system carries six complementary patterns and
allows six-level µCP with a layer-to-layer accuracy of 10 µm over a 5 mm x 5 mm area
without the use of external aligning equipment. This is the first such report of aligned
multilevel µCP.
Lastly, the integration of the replica moulded engine with a hydraulic drive for controlled
actuation is investigated. This approach is promising and proof of concept has been provided
for single-level patterning
Super-resolution spatial, temporal and functional characterisation of voltage-gated calcium channels involved in exocytosis
The
process
of
information
transfer
between
neurons
or
endocrine
cells
is
one
of
the
most
important,
intricate
and
temporally
precise
processes
in
the
body.
Exocytosis,
which
is
central
to
the
process
of
excitation-‐secretion
coupling,
is
triggered
by
calcium
signalling
through
voltage-‐gated
calcium
channels.
Super-‐resolution
imaging
offers
the
possibility
to
fully
understand
the
spatial
relationship
between
the
SNARE
proteins
involved
in
exocytosis,
vesicles
and
the
associated
voltage-‐gated
calcium
channels.
In
this
thesis
the
focus
is
on
exploring
the
trigger
for
exocytosis,
specifically
the
spatial
and
functional
role
that
voltage-‐gated
calcium
channels
play
in
this
process.
Super-‐
resolution
imaging
techniques
have
been
applied
to
measure
the
interaction
between
Cav2.2
calcium
channels
and
the
syntaxin1a
SNARE
protein,
where
binding
was
found
to
affect
the
overall
channel
distribution.
A
novel
method
of
caged
dye
conjugated
ω-‐
conotoxin
GVIA
binding
was
developed
for
live
cell
single
molecule
imaging
of
Cav2.2
calcium
channels.
An
innovative
approach
to
analyse
channel
functionality
and
the
distribution
of
calcium
events
at
the
plasma
membrane
was
developed
to
create
a
temporal-‐spatial
map
of
calcium
activity
across
the
cell.
These
developments,
combined
with
newly
developed
techniques
in
optical
patching
and
simultaneous
calcium
and
vesicle
imaging
reveal
the
functional
relationship
of
voltage-‐gated
calcium
channel
and
exocytosis
at
unprecedented
spatial
and
temporal
scales
Longitudinal flying qualities criteria for single-pilot instrument flight operations
Modern estimation and control theory, flight testing, and statistical analysis were used to deduce flying qualities criteria for General Aviation Single Pilot Instrument Flight Rule (SPIFR) operations. The principal concern is that unsatisfactory aircraft dynamic response combined with high navigation/communication workload can produce problems of safety and efficiency. To alleviate these problems. The relative importance of these factors must be determined. This objective was achieved by flying SPIFR tasks with different aircraft dynamic configurations and assessing the effects of such variations under these conditions. The experimental results yielded quantitative indicators of pilot's performance and workload, and for each of them, multivariate regression was applied to evaluate several candidate flying qualities criteria
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