6,340 research outputs found
Doubly Contrastive End-to-End Semantic Segmentation for Autonomous Driving under Adverse Weather
Road scene understanding tasks have recently become crucial for self-driving
vehicles. In particular, real-time semantic segmentation is indispensable for
intelligent self-driving agents to recognize roadside objects in the driving
area. As prior research works have primarily sought to improve the segmentation
performance with computationally heavy operations, they require far significant
hardware resources for both training and deployment, and thus are not suitable
for real-time applications. As such, we propose a doubly contrastive approach
to improve the performance of a more practical lightweight model for
self-driving, specifically under adverse weather conditions such as fog,
nighttime, rain and snow. Our proposed approach exploits both image- and
pixel-level contrasts in an end-to-end supervised learning scheme without
requiring a memory bank for global consistency or the pretraining step used in
conventional contrastive methods. We validate the effectiveness of our method
using SwiftNet on the ACDC dataset, where it achieves up to 1.34%p improvement
in mIoU (ResNet-18 backbone) at 66.7 FPS (2048x1024 resolution) on a single RTX
3080 Mobile GPU at inference. Furthermore, we demonstrate that replacing
image-level supervision with self-supervision achieves comparable performance
when pre-trained with clear weather images.Comment: Accepted for publication at BMVC 202
DNA-linked nanoparticle building blocks for nanostructure assembly and methods of producing the same
A method of producing a nanoparticle assembly. The method includes attaching a first DNA molecule to a bead to form a first DNA-bead complex; and combining a nanoparticle with the first DNA-bead complex to form a nanoparticle-DNA-bead complex having one DNA molecule attached to the nanoparticle
Electrochemical Investigation of High-Performance Dye-Sensitized Solar Cells Based on Molybdenum for Preparation of Counter Electrode
In order to improve the photocurrent conversion efficiency of dye-sensitized solar cells (DSSCs), we studied an alternative conductor for the counter electrode and focused on molybdenum (Mo) instead of conventional fluorine-doped tin oxide (FTO). Because Mo has a similar work function to FTO for band alignment, better formability of platinum (Pt), and a low electric resistance, using a counter electrode made of Mo instead of FTO lead to the enhancement of the catalytic reaction of the redox couple, reduce the interior resistance of the DSSCs, and prevent energy-barrier formation. Using electrical measurements under a 1-sun condition (100 mW/cm(2), AM 1.5), we determined that the fill factor (FF) and photocurrent conversion efficiency (eta) of DSSCs with a Mo electrode were respectively improved by 7.75% and 5.59% with respect to those of DSSCs with an FTO electrode. Moreover, we have investigated the origin of the improved performance through surface morphology analyses such as scanning electron microscopy and electrochemical analyses including cyclic voltammetry and impedance spectroscopy
Engineering criticality analysis on an offshore structure using the first- and second-order reliability method
AbstractDue to the uncertainties related to the flaw assessment parameters, such as flaw size, fracture toughness, loading spectrum and so on, the probability concept is preferred over deterministic one in flaw assessment. In this study, efforts have been made to develop the reliability based flaw assessment procedure which combines the flaw assessment procedure of BS7910 and first- and second-order reliability methods (FORM/SORM). Both crack length and depth of semi-elliptical surface crack at weld toe were handled as random variable whose probability distribution was defined as Gaussian with certain means and standard deviations. Then the limit state functions from static rupture and fatigue perspective were estimated using FORM and SORM in joint probability space of crack depth and length. The validity of predicted limit state functions were checked by comparing it with those obtained by Monte Carlo simulation. It was confirmed that the developed methodology worked perfectly in predicting the limit state functions without time-consuming Monte Carlo simulation
The performing arts based on intermedia in Korea: the case of musical and madanggeuk
This article introduces musicals and ‘madanggeuk’ among the most beloved performing arts in Korea. Contrary to textual literature, performing arts exist only through performances on the stage, so it can be said to be one-time arts that disappear when the performances are over. However, even if it is one-off, the development of the plot in all types of performing arts can not proceed without the basis of narration or story-telling. Performing arts such as musicals and ‘madanggeuk’ are also often referred to as composite arts because they need help with stage, lighting, sound, and choreography. These two have a commonality that they overcome various constraints such as the ‘space constraint’ of the stage and the ‘time constraint’ of the performance, and perform the most appropriate and implicit performance. On the other hand, they are also distinguishable; musicals show the domestic acceptance of globality, and ‘madanggeuk’ the modern succession of Korean locality. Musicals and ‘madanggeuk’ have become a genre of contemporary art in the short chronology, and furthermore, also provide additional content that creates diverse forms by adding elements of music and dance to the story’s strength of the original work. Korean musicals and ‘madanggeuk’ are also based on the notion of ‘trans-’ or ‘hybrid-’ in the ecosystem of literature and art in terms of transcending or expanding. Both genres already embrace the possibilities and status as ‘glocal’ arts, but they are still being forced to create new stories in a multi-media environment and new storytelling work
Non-invasive algorithm for bowel motility estimation using a back-propagation neural network model of bowel sounds
<p>Abstract</p> <p>Background</p> <p>Radiological scoring methods such as colon transit time (CTT) have been widely used for the assessment of bowel motility. However, these radiograph-based methods need cumbersome radiological instruments and their frequent exposure to radiation. Therefore, a non-invasive estimation algorithm of bowel motility, based on a back-propagation neural network (BPNN) model of bowel sounds (BS) obtained by an auscultation, was devised.</p> <p>Methods</p> <p>Twelve healthy males (age: 24.8 ± 2.7 years) and 6 patients with spinal cord injury (6 males, age: 55.3 ± 7.1 years) were examined. BS signals generated during the digestive process were recorded from 3 colonic segments (ascending, descending and sigmoid colon), and then, the acoustical features (jitter and shimmer) of the individual BS segment were obtained. Only 6 features (<it>J<sub>1, 3</sub>, J<sub>3, 3</sub>, S<sub>1, 2</sub>, S<sub>2, 1</sub>, S<sub>2, 2</sub>, S<sub>3, 2</sub></it>), which are highly correlated to the CTTs measured by the conventional method, were used as the features of the input vector for the BPNN.</p> <p>Results</p> <p>As a results, both the jitters and shimmers of the normal subjects were relatively higher than those of the patients, whereas the CTTs of the normal subjects were relatively lower than those of the patients (<it>p </it>< 0.01). Also, through <it>k</it>-fold cross validation, the correlation coefficient and mean average error between the CTTs measured by a conventional radiograph and the values estimated by our algorithm were 0.89 and 10.6 hours, respectively.</p> <p>Conclusions</p> <p>The jitter and shimmer of the BS signals generated during the peristalsis could be clinically useful for the discriminative parameters of bowel motility. Also, the devised algorithm showed good potential for the continuous monitoring and estimation of bowel motility, instead of conventional radiography, and thus, it could be used as a complementary tool for the non-invasive measurement of bowel motility.</p
Squeezing Limit of the Josephson Ring Modulator as a Non-Degenerate Parametric Amplifier
Two-mode squeezed vacuum states are a crucial component of quantum
technologies. In the microwave domain, they can be produced by Josephson ring
modulator which acts as a three-wave mixing non-degenerate parametric
amplifier. Here, we solve the master equation of three bosonic modes describing
the Josephson ring modulator with a novel numerical method to compute squeezing
of output fields and gain at low signal power. We show that the third-order
interaction from the three-wave mixing process intrinsically limits squeezing
and reduces gain. Since our results are related to other general cavity-based
three-wave mixing processes, these imply that any non-degenerate parametric
amplifier will have an intrinsic squeezing limit in the output fields.Comment: 6+6 pages, 4 figure
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