143 research outputs found
Approaches to creating anonymous patient database
Health care providers, health plans and health care clearinghouses collect patient medical data derived from their normal operations every day. These patient data can greatly benefit the health care organization if data mining techniques are applied upon these data sets. However, individual identifiable patient information needs to be protected in accordance with Health Insurance Portability and Accountability Act (HIPAA), and the quality of patient data also needs to be ensured in order for data mining tasks achieve accurate results. This thesis describes a patient data transformation system which transforms patient data into high quality and anonymous patient records that is suitable for data mining purposes.;This document discusses the underlying technologies, features implemented in the prototype, and the methodologies used in developing the software. The prototype emphasizes the patient privacy and quality of the patient data as well as software scalability and portability. Preliminary experience of its use is presented. A performance analysis of the system\u27s behavior has also been done
Link between K-absorption edges and thermodynamic properties of warm-dense plasmas established by improved first-principles method
A precise calculation that translates shifts of X-ray K-absorption edges to
variations of thermodynamic properties allows quantitative characterization of
interior thermodynamic properties of warm dense plasmas by X-ray absorption
techniques, which provides essential information for inertial confinement
fusion and other astrophysical applications. We show that this interpretation
can be achieved through an improved first-principles method. Our calculation
shows that the shift of K-edges exhibits selective sensitivity to thermal
parameters and thus would be a suitable temperature index to warm dense
plasmas. We also show with a simple model that the shift of K-edges can be used
to detect inhomogeneity inside warm dense plasmas when combined with other
experimental tools
Deep Network Approximation: Achieving Arbitrary Accuracy with Fixed Number of Neurons
This paper develops simple feed-forward neural networks that achieve the
universal approximation property for all continuous functions with a fixed
finite number of neurons. These neural networks are simple because they are
designed with a simple and computable continuous activation function
leveraging a triangular-wave function and the softsign function. We prove that
-activated networks with width and depth can
approximate any continuous function on a -dimensional hypercube within an
arbitrarily small error. Hence, for supervised learning and its related
regression problems, the hypothesis space generated by these networks with a
size not smaller than is dense in the continuous function
space and therefore dense in the Lebesgue spaces
for . Furthermore, classification functions arising from image
and signal classification are in the hypothesis space generated by
-activated networks with width and depth , when there
exist pairwise disjoint bounded closed subsets of such that the
samples of the same class are located in the same subset. Finally, we use
numerical experimentation to show that replacing the ReLU activation function
by ours would improve the experiment results
First-Principles Calculation of Principal Hugoniot and K-Shell X-ray Absorption Spectra for Warm Dense KCl
Principal Hugoniot and K-shell X-ray absorption spectra of warm dense KCl are
calculated using the first-principles molecular dynamics method. Evolution of
electronic structures as well as the influence of the approximate description
of ionization on pressure (caused by the underestimation of the energy gap
between conduction bands and valence bands) in the first-principles method are
illustrated by the calculation. Pressure ionization and thermal smearing are
shown as the major factors to prevent the deviation of pressure from global
accumulation along the Hugoniot. In addition, cancellation between electronic
kinetic pressure and virial pressure further reduces the deviation. The
calculation of X-ray absorption spectra shows that the band gap of KCl persists
after the pressure ionization of the electrons of Cl and K taking place at
lower energy, which provides a detailed understanding to the evolution of
electronic structures of warm dense matter
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