986 research outputs found
A joint time-invariant filtering approach to the linear Gaussian relay problem
In this paper, the linear Gaussian relay problem is considered. Under the
linear time-invariant (LTI) model the problem is formulated in the frequency
domain based on the Toeplitz distribution theorem. Under the further assumption
of realizable input spectra, the LTI Gaussian relay problem is converted to a
joint design problem of source and relay filters under two power constraints,
one at the source and the other at the relay, and a practical solution to this
problem is proposed based on the projected subgradient method. Numerical
results show that the proposed method yields a noticeable gain over the
instantaneous amplify-and-forward (AF) scheme in inter-symbol interference
(ISI) channels. Also, the optimality of the AF scheme within the class of
one-tap relay filters is established in flat-fading channels.Comment: 30 pages, 10 figure
Assume the position: reconfiguring the spatial in the pre-service education classroom
Current understandings of the practice of education locate pedagogy in the public domain through the articulation of the personal domain (Pinar, 2004). Critical literacy has provided teachers and teacher educators with a means of transforming subjectivity and relocating the personal through writing (Kamler, 2001). The emphasis in a critical literacy approach on the spoken and written word sits comfortably in the academic discourse of tertiary education, although it\u27s engagement with the personal meets with some resistance. However, to engage the personal through arts based approaches meets far greater resistance. When used as the medium for core educational studies it provokes passionate responses of both dissent and accord. The authors argue the possibilities for an arts based pedagogy in pre-service education which provides a space for learning outside the accepted academic discourse and which supports the possibilities of imaging and knowing the positioned teacher. This research (dis)locates (Laclau, 1990; Edwards and Usher, 1997) the spatial configuration of the tertiary education classroom: reconfiguring the physical, positional, and epistemological.<br /
Intensity-Based Image Registration Using Robust Correlation Coefficients
The ordinary sample correlation coefficient is a
popular similarity measure for aligning images from the same
or similar modalities. However, this measure can be sensitive to
the presence of āoutlierā objects that appear in one image but
not the other, such as surgical instruments, the patient table, etc.,
which can lead to biased registrations. This paper describes an
intensity-based image registration technique that uses a robust
correlation coefficient as a similarity measure. Relative to the
ordinary sample correlation coefficient, the proposed similarity
measure reduces the influence of outliers. We also compared the
performance of the proposed method with the mutual information-
based method. The robust correlation-based method should
be useful for image registration in radiotherapy (KeV to MeV
X-ray images) and image-guided surgery applications. We have
investigated the properties of the proposed method by theoretical
analysis, computer simulations, a phantom experiment, and with
functional magnetic resonance imaging data.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/85801/1/Fessler55.pd
Study on high throughput nanomanufacturing of photopatternable nanofibers using tube nozzle electrospinning with multi-tubes and multi-nozzles
High throughput nanomanufacturing of photopatternable nanofibers and subsequent photopatterning is reported. For the production of high density nanofibers, the tube nozzle electrospinning (TNE) process has been used, where an array of micronozzles on the sidewall of a plastic tube are used as spinnerets. By increasing the density of nozzles, the electric fields of adjacent nozzles confine the cone of electrospinning and give a higher density of nanofibers. With TNE, higher density nozzles are easily achievable compared to metallic nozzles, e.g. an inter-nozzle distance as small as 0.5 cm and an average semi-vertical repulsion angle of 12.28Ā° for 8-nozzles were achieved. Nanofiber diameter distribution, mass throughput rate, and growth rate of nanofiber stacks in different operating conditions and with different numbers of nozzles, such as 2, 4 and 8 nozzles, and scalability with single and double tube configurations are discussed. Nanofibers made of SU-8, photopatternable epoxy, have been collected to a thickness of over 80 Ī¼m in 240 s of electrospinning and the production rate of 0.75 g/h is achieved using the 2 tube 8 nozzle systems, followed by photolithographic micropatterning. TNE is scalable to a large number of nozzles, and offers high throughput production, plug and play capability with standard electrospinning equipment, and little waste of polymer. Ā© 2017, The Author(s)
Functional consequences of cell type-restricted expression of laminin alpha-5 in mouse placental labyrinth and kidney glomerular capillaries
The labyrinth is the highly vascularized part of the rodent placenta that allows efficient transfer of gases, nutrients, wastes, and other molecules between the maternal and embryonic circulations. These two blood compartments are separated by blastocyst-derived trophoblasts and endothelial cells with an intervening basement membrane that contains laminin and other typical basement membrane components. Previously we reported that the labyrinth of laminin Ī±5 knockout (LMĪ±5ā/ā) embryos exhibits reduced vascularization and detachment of endothelial cells from the basement membrane, which normally contains LMĪ±5. As very little is known about the origin of this vascular basement membrane, we investigated the cellular requirements for LMĪ±5 expression in the mouse placental labyrinth. By fluorescence-activated cell sorting and RT-PCR we confirmed that both endothelial cells and trophoblasts normally express LMĪ±5. Using Cre-loxP technology and doxycycline-mediated gene expression, we generated genetically mosaic placentas in which either the trophoblasts or the endothelial cells, but not both, expressed LMĪ±5. We found that the overall architecture of the labyrinth was normal as long as one of these two cell types expressed LMĪ±5, even if it was transgene-derived human laminin Ī±5. These results suggest that laminin trimers containing Ī±5 that are synthesized and secreted by endothelium or by trophoblasts are capable of integrating into the basement membrane and promoting normal vascularization of the placenta. Additional studies showed that endothelium-expressed human LMĪ±5 can support vascularization of the kidney glomerulus, consistent with previous studies using a tissue grafting approach
Assessing Myocardial Perfusion after Myocardial Infarction
Ashrafian and colleagues describe the use of myocardial contrast echocardiography to assess a 63-year-old man with ischemic heart disease
Moments in time: investigating the Australian history curriculum in primary classrooms: final report 2015
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