468 research outputs found
The approach to urethral obstruction in the cat: Part 2:Catheterising and post obstruction management
Ranking algorithms for implicit feedback
This report presents novel algorithms to use eye movements as an implicit relevance feedback in order to improve the performance of the searches. The algorithms are evaluated on "Transport Rank Five" Dataset which were previously collected in Task 8.3. We demonstrated that simple linear combination or tensor product of eye movement and image features can improve the retrieval accuracy
Approach to urethral obstruction in the cat: Part 3:addressing underlying concerns and preventing recurrence
CCD Readout Electronics for the Subaru Prime Focus Spectrograph
We present details of the design for the CCD readout electronics for the
Subaru Telescope Prime Focus Spectrograph (PFS). The spectrograph is comprised
of four identical spectrograph modules, each collecting roughly 600 spectra.
The spectrograph modules provide simultaneous wavelength coverage over the
entire band from 380 nm to 1260 nm through the use of three separate optical
channels: blue, red, and near infrared (NIR). A camera in each channel images
the multi-object spectra onto a 4k x 4k, 15 um pixel, detector format. The two
visible cameras use a pair of Hamamatsu 2k x 4k CCDs with readout provided by
custom electronics, while the NIR camera uses a single Teledyne HgCdTe 4k x 4k
detector and ASIC Sidecar to read the device.
The CCD readout system is a custom design comprised of three electrical
subsystems: the Back End Electronics (BEE), the Front End Electronics (FEE),
and a Pre-amplifier. The BEE is an off-the-shelf PC104 computer, with an
auxiliary Xilinx FPGA module. The computer serves as the main interface to the
Subaru messaging hub and controls other peripheral devices associated with the
camera, while the FPGA is used to generate the necessary clocks and transfer
image data from the CCDs. The FEE board sets clock biases, substrate bias, and
CDS offsets. It also monitors bias voltages, offset voltages, power rail
voltage, substrate voltage and CCD temperature. The board translates LVDS clock
signals to biased clocks and returns digitized analog data via LVDS. Monitoring
and control messages are sent from the BEE to the FEE using a standard serial
interface. The Pre-amplifier board resides behind the detectors and acts as an
interface to the two Hamamatsu CCDs. The Pre-amplifier passes clocks and biases
to the CCDs, and analog CCD data is buffered and amplified prior to being
returned to the FEE.Comment: 14 pages, 15 figures, SPIE ATI 2014, Montrea
Unrestricted Release Measurements with Ambient Air Ionization Monitors
ABSTRACT Radiation monitoring systems based on the long-range alpha detection (LRAD) technique, such as the BNFL Instruments IonSens, provide a single contamination measurement for an entire object rather than the more familiar series of individual readings for smaller surface areas. The LRAD technique relies on the ionization of ambient air molecules by alpha particles, and the subsequent detection of these ions, rather than direct detection of the alpha particles themselves. A single monitor can detect all of the ions produced over a large object (pipe, I-beam, reinforcing bar, etc.) and report a total contamination level for the entire surface of that object. Currently, both the unrestricted release limits specified in USDOE Order 5400.5 (and similar documents in other countries), and the definitions of radioactive waste categories, are stated in terms of contamination per area (e.g. 20 dpm/100 cm
Visible camera cryostat design and performance for the SuMIRe Prime Focus Spectrograph (PFS)
We describe the design and performance of the SuMIRe Prime Focus Spectrograph
(PFS) visible camera cryostats. SuMIRe PFS is a massively multi-plexed
ground-based spectrograph consisting of four identical spectrograph modules,
each receiving roughly 600 fibers from a 2394 fiber robotic positioner at the
prime focus. Each spectrograph module has three channels covering wavelength
ranges 380~nm -- 640~nm, 640~nm -- 955~nm, and 955~nm -- 1.26~um, with the
dispersed light being imaged in each channel by a f/1.07 vacuum Schmidt camera.
The cameras are very large, having a clear aperture of 300~mm at the entrance
window, and a mass of 280~kg. In this paper we describe the design of the
visible camera cryostats and discuss various aspects of cryostat performance
- …