8,236 research outputs found
Inferring Missing Entity Type Instances for Knowledge Base Completion: New Dataset and Methods
Most of previous work in knowledge base (KB) completion has focused on the
problem of relation extraction. In this work, we focus on the task of inferring
missing entity type instances in a KB, a fundamental task for KB competition
yet receives little attention. Due to the novelty of this task, we construct a
large-scale dataset and design an automatic evaluation methodology. Our
knowledge base completion method uses information within the existing KB and
external information from Wikipedia. We show that individual methods trained
with a global objective that considers unobserved cells from both the entity
and the type side gives consistently higher quality predictions compared to
baseline methods. We also perform manual evaluation on a small subset of the
data to verify the effectiveness of our knowledge base completion methods and
the correctness of our proposed automatic evaluation method.Comment: North American Chapter of the Association for Computational
Linguistics- Human Language Technologies, 201
Guiding Vascular Access with the Sonic Flashlight - Preclinical Development and Validation
This dissertation concerns the development of a device called the Sonic Flashlight, which employs a novel method for viewing real-time ultrasound images inside the body exactly at the location where it is being scanned. While other augmented reality methods have previously been developed to view ultrasound and other medical imaging modalities within the body, they are generally much more complicated, slower and less robust than the Sonic Flashlight.In this dissertation, we aim to develop the Sonic Flashlight towards one particular clinical application, central vascular access, and lay the groundwork leading to the first clinical trials. The goal of central vascular access is to insert a catheter into a major vein to deliver medications in large quantities. These veins are usually not visible to the naked eye, so real-time ultrasound is employed to guide the needle into them. While real-time ultrasound guidance significantly enhances the safety of central venous access, learning this skill can be a challenge for the novice user, one major obstacle being the displaced sense of hand-eye coordination that occurs when the operator must look away from the operating field to view the conventional ultrasound monitor.We developed the 5th generation Sonic Flashlight, as well as a novel calibration method, called thin-gel calibration, as part of this dissertation. The thin-gel system allows us to accurately calibrate the Sonic Flashlight and measure the calibration accuracy. Finally, experiments were conducted with a variety of subject populations using vascular ultrasound phantoms and cadavers to validate Sonic Flashlight guidance, demonstrating that the device is ready for clinical trials
Rashba Spin Interferometer
A spin interferometer utilizing the Rashba effect is proposed. The novel
design is composed of a one-dimensional (1D) straight wire and a 1D half-ring.
By calculating the norm of the superposed wave function, we derive analytical
expressions to describe the spin interference spectrum as a function of the
Rashba coupling strength. Presented spin interference results are identified to
include (i) the quantum-mechanical 4pi rotation effect, (ii) geometric effect,
and (iii) Shubnikov-de Haas-like beating effect.Comment: 3 pages, 3 figures, appears in the proceedings of the 10th Joint
MMM/Intermag Conferenc
Quantum World-line Monte Carlo Method with Non-binary Loops and Its Application
A quantum world-line Monte Carlo method for high-symmetrical quantum models
is proposed. Firstly, based on a representation of a partition function using
the Matsubara formula, the principle of quantum world-line Monte Carlo methods
is briefly outlined and a new algorithm using non-binary loops is given for
quantum models with high symmetry as SU(N). The algorithm is called non-binary
loop algorithm because of non-binary loop updatings. Secondary, one example of
our numerical studies using the non-binary loop updating is shown. It is the
problem of the ground state of two-dimensional SU(N) anti-ferromagnets. Our
numerical study confirms that the ground state in the small N <= 4 case is a
magnetic ordered Neel state, but the one in the large N >= 5 case has no
magnetic order, and it becomes a dimer state.Comment: 14 pages, 5 figures, Invited talk at the 18th Annual Workshop on
Recent Developments of Computer Simulation Studies in Condensed Matter
Physics, Athens, 7-11 March, 200
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