1,658 research outputs found
Sparsely Aggregated Convolutional Networks
We explore a key architectural aspect of deep convolutional neural networks:
the pattern of internal skip connections used to aggregate outputs of earlier
layers for consumption by deeper layers. Such aggregation is critical to
facilitate training of very deep networks in an end-to-end manner. This is a
primary reason for the widespread adoption of residual networks, which
aggregate outputs via cumulative summation. While subsequent works investigate
alternative aggregation operations (e.g. concatenation), we focus on an
orthogonal question: which outputs to aggregate at a particular point in the
network. We propose a new internal connection structure which aggregates only a
sparse set of previous outputs at any given depth. Our experiments demonstrate
this simple design change offers superior performance with fewer parameters and
lower computational requirements. Moreover, we show that sparse aggregation
allows networks to scale more robustly to 1000+ layers, thereby opening future
avenues for training long-running visual processes.Comment: Accepted to ECCV 201
Learning to Navigate Cloth using Haptics
We present a controller that allows an arm-like manipulator to navigate
deformable cloth garments in simulation through the use of haptic information.
The main challenge of such a controller is to avoid getting tangled in, tearing
or punching through the deforming cloth. Our controller aggregates force
information from a number of haptic-sensing spheres all along the manipulator
for guidance. Based on haptic forces, each individual sphere updates its target
location, and the conflicts that arise between this set of desired positions is
resolved by solving an inverse kinematic problem with constraints.
Reinforcement learning is used to train the controller for a single
haptic-sensing sphere, where a training run is terminated (and thus penalized)
when large forces are detected due to contact between the sphere and a
simplified model of the cloth. In simulation, we demonstrate successful
navigation of a robotic arm through a variety of garments, including an
isolated sleeve, a jacket, a shirt, and shorts. Our controller out-performs two
baseline controllers: one without haptics and another that was trained based on
large forces between the sphere and cloth, but without early termination.Comment: Supplementary video available at https://youtu.be/iHqwZPKVd4A.
Related publications http://www.cc.gatech.edu/~karenliu/Robotic_dressing.htm
Interval Parsing Grammars for File Format Parsing
File formats specify how data is encoded for persistent storage. They cannot
be formalized as context-free grammars since their specifications include
context-sensitive patterns such as the random access pattern and the
type-length-value pattern. We propose a new grammar mechanism called Interval
Parsing Grammars IPGs) for file format specifications. An IPG attaches to every
nonterminal/terminal an interval, which specifies the range of input the
nonterminal/terminal consumes. By connecting intervals and attributes, the
context-sensitive patterns in file formats can be well handled. In this paper,
we formalize IPGs' syntax as well as its semantics, and its semantics naturally
leads to a parser generator that generates a recursive-descent parser from an
IPG. In general, IPGs are declarative, modular, and enable termination
checking. We have used IPGs to specify a number of file formats including ZIP,
ELF, GIF, PE, and part of PDF; we have also evaluated the performance of the
generated parsers.Comment: To appear on PLDI'2
In-depth critical analysis of complications following robot-assisted radical cystectomy with intracorporeal urinary diversion
Background:
Robot-assisted radical cystectomy with intracorporeal urinary diversion (iRARC) is an attractive option to open cystectomy, but the benefit in terms of improved outcomes is not established.
Objective:
To evaluate the early postoperative morbidity and mortality of patients undergoing iRARC and conduct a critical analysis of complications using standardised reporting criteria as stratified according to urinary diversion.
Design, setting, and participants:
A total of 134 patients underwent iRARC for bladder cancer at a single centre between June 2011 and July 2015.
Intervention:
Radical cystectomy with iRARC.
Outcome measurements and statistical analysis:
Patient demographics, pathologic data, and 90-d perioperative mortality and complications were recorded. Complications were reported according to the Clavien-Dindo (CD) classification and stratified according to urinary diversion type and either surgical or medical complications. The chi-square test and t test were used for categorical and continuous variables respectively. Multivariable logistic regression was performed on variables with significance in univariate analysis.
Results and limitations:
The 90-d all complication rate following ileal conduit and continent diversion was 68% and 82.4%, and major complications were 21.0% and 20.6% respectively. The 90-d mortality was 3% and 2.9% for ileal conduit and continent diversion patients, respectively. On multivariate analysis, the blood transfusion requirement was independently associated with major complications (p = 0.002) and all 30-d (p = 0.002) and 90-d (p = 0.012) major complications. Male patients were associated with 90-d major complications (p = 0.015). Critical analysis identified that surgical complications were responsible for 39.4% of all 90-d major complications. The incidence of surgical complications did not decline with increasing number of iRARC cases performed (p = 0.742, r = 0.31). Limitations of this study include its retrospective nature, limited sample size, and limited multivariate analysis due to the low number of major complications events.
Conclusions:
Although complications following iRARC are common, most are low grade. A critical analysis identified surgical complications as a cause of major complications. Addressing this issue could have a significant impact on lowering the morbidity associated with iRARC.
Patient summary:
We looked at the surgical outcomes in bladder cancer patients treated with minimally invasive robotic surgery. We found that surgical complications account for most major complications and previous surgical experience may be a confounding factor when interpreting results from a different centre even in a randomised trial setting
User Views On The Complex Accounting For Financial Instruments
This paper examines Australian and Singaporean users’ views on fair value accounting for all financial instruments in financial institutions via a survey on various aspects of contention in this debate. Overall, users showed general support for fair value accounting for all financial instruments. In addition, the findings revealed that users will support fair value accounting so long as there is no perceived difference between the banking and trading books, fair values of non-traded financial instruments are reliable and volatility in earnings will not be misunderstood. It was also found that user experience increases the level of support for the proposed fair value accounting model. These results highlight actual user preferences with noticeable support for arguments from both sides of the debate (JWG and JWGBA) in this highly contentious and topical area of accounting for financial instruments
Electron-hole recombination properties of In0.5Ga0.5As/GaAs quantum dot solar cells and the influence on the open circuit voltage
We report on a detailed analysis of the temperature dependent electrical properties of In0.5Ga0.5As/GaAsquantum dotsolar cells. The effects leading to a reduction in the open circuit voltage are found to be the thermal injection of carriers from the n and p-type layers into the depletion region where they recombine with carriers occupying quantum dot states due to a thermal distribution. The departure of the device studied here from an ideal intermediate band solar cell is discussed.Thanks are due to the Australian Research Council for
the financial support of this research and the Australian National
Fabrication Facility for access to the facilities used in
this work
Plasmonic quantum dot solar cells for enhanced infrared response
Enhanced near infrared photoresponse in plasmonic InGaAs/GaAs quantum dotsolar cells (QDSC) is demonstrated. Long wavelength light absorption in the wetting-layer and quantum-dot region of the quantum dotsolar cell is enhanced through scattering of light by silver nanoparticles deposited on the solar cellsurface.Plasmonic light trapping results in simultaneous increase in short-circuit current density by 5.3% and open circuit voltage by 0.9% in the QDSC, leading to an overall efficiency enhancement of 7.6%.This work was supported by the Australian Research
Council (Grant No. DP1096361)
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