19,077 research outputs found
Dynamical Component Analysis (DyCA) and its application on epileptic EEG
Dynamical Component Analysis (DyCA) is a recently-proposed method to detect
projection vectors to reduce the dimensionality of multi-variate deterministic
datasets. It is based on the solution of a generalized eigenvalue problem and
therefore straight forward to implement. DyCA is introduced and applied to EEG
data of epileptic seizures. The obtained eigenvectors are used to project the
signal and the corresponding trajectories in phase space are compared with PCA
and ICA-projections. The eigenvalues of DyCA are utilized for seizure detection
and the obtained results in terms of specificity, false discovery rate and miss
rate are compared to other seizure detection algorithms.Comment: 5 pages, 4 figures, accepted for IEEE International Conference on
Acoustics, Speech and Signal Processing (ICASSP) 201
Preparation of Nanocomposites from Styrene and Modified Graphite Oxides
Graphite oxide was prepared and modified with several ammonium salts and these modified graphite oxides were used to prepare nanocomposites with polystyrene by in situ polymerization of styrene monomer and by melt blending with polystyrene. Nanocomposites were characterized by X-ray diffraction, cone calorimetry, thermogravimetric analysis and the evaluation of mechanical properties. Nanocomposites are formed by in situ polymerization but not by melt blending; the graphite oxide undergoes thermal degradation at the temperature of melt blending so nanocomposite formation would be unlikely. Mechanical properties of the melt blended nanocomposites are improved relative to the virgin polystyrene while those prepared by in situ polymerization are decreased, except in the case of Young\u27s Modulus, where melt blended and in situ polymerized materials show similar results
Polybutadiene Cross-Linked With Various Diols – Effect On Thermal Stability
The relationship between cross-linking and thermal stability as related to polybutadiene is the focus of current research. Cross-linked polybutadienes have been prepared using various diols as the cross-linking agent. Cross-linked polymers have been characterized by gel content, swelling ratios, infrared spectroscopy, and thermal analysis. These polymers are not highly cross-linked, as seen by gel content and swelling ratios, and cross-linking does not have a large effect on the onset temperature of the degradation. Nonetheless, extensive formation of a non-volatile residue occurs
Detection of fixed points in spatiotemporal signals by clustering method
We present a method to determine fixed points in spatiotemporal signals. A
144-dimensioanl simulated signal, similar to a Kueppers-Lortz instability, is
analyzed and its fixed points are reconstructed.Comment: 3 pages, 3 figure
State Fiscal Policies and Regional Economic Activity
In this paper, I estimate a structural panel vector autoregression to study the consequences of changes in U.S. state government fiscal policies for local economic activity in the short-term. My main result is that the state-level spending multiplier is relatively small and the tax multiplier relatively large. After four years, the government spending multiplier is 0.6 and the tax multiplier -2.62. This conclusion is found to be robust across different model specifications. I also find that both state spending and state revenue shocks increase out of state output
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