Algorithmic Clustering of Music

We present a fully automatic method for music classification, based only on compression of strings that represent the music pieces. The method uses no background knowledge about music whatsoever: it is completely general and can, without change, be used in different areas like linguistic classification and genomics. It is based on an ideal theory of the information content in individual objects (Kolmogorov complexity), information distance, and a universal similarity metric. Experiments show that the method distinguishes reasonably well between various musical genres and can even cluster pieces by composer.Comment: 17 pages, 11 figure

Poly(1,3,4-oxadiazoles) via aromatic nucleophilic displacement

Poly(1,3,4-oxadiazoles) (POX) are prepared by the aromatic nucleophilic displacement reaction of di(hydroxyphenyl) 1,3,4-oxadiazole monomers with activated aromatic dihalides or activated aromatic dinitro compounds. The polymerizations are carried out in polar aprotic solvents such as sulfolane or diphenylsulfone using alkali metal bases such as potassium carbonate at elevated temperatures under nitrogen. The di(hydroxyphenyl) 1,3,4-oxadiazole monomers are synthesized by reacting 4-hydroxybenzoic hydrazide with phenyl 4-hydrobenzoate in the melt and also by reacting aromatic dihydrazides with two moles of phenyl 4-hydroxybenzoate in the melt. This synthetic route has provided high molecular weight POX of new chemical structure, is economically and synthetically more favorable than other routes, and allows for facile chemical structure variation due to the large variety of activated aromatic dihalides which are available

Island Distance in One-Dimensional Epitaxial Growth

The typical island distance $\ell$ in submonlayer epitaxial growth depends on the growth conditions via an exponent $\gamma$. This exponent is known to depend on the substrate dimensionality, the dimension of the islands, and the size $i^*$ of the critical nucleus for island formation. In this paper we study the dependence of $\gamma$ on $i^*$ in one--dimensional epitaxial growth. We derive that $\gamma = i^*/(2i^* + 3)$ for $i^*\geq 2$ and confirm this result by computer simulations.Comment: 5 pages, 3 figures, uses revtex, psfig, 'Note added in proof' appende

Comment on "Test of constancy of speed of light with rotating cryogenic optical resonators"

A recent experiment by Antonini et. al. [Phys. Rev. A {\bf 71}, 050101R 2005], set new limits on Lorentz violating parameters in the frame-work of the photon sector of the Standard Model Extension (SME), $\tilde{\kappa}_{e-}^{ZZ}$, and the Robertson-Mansouri-Sexl (RMS) framework, $\beta-\delta-1/2$. The experiment had significant systematic effects caused by the rotation of the apparatus which were only partly analysed and taken into account. We show that this is insufficient to put a bound on $\tilde{\kappa}_{e-}^{ZZ}$ and the bound on $\beta-\delta-1/2$ represents a five-fold improvement not a ten-fold improvement as claimed. (For reply see Phys. Rev. A 72, 066102 (2005) DOI: 10.1103/PhysRevA.72.066102)Comment: 2 page

A Compressed Sensing Algorithm for Sparse-View Pinhole Single Photon Emission Computed Tomography

Single Photon Emission Computed Tomography (SPECT) systems are being developed with multiple cameras and without gantry rotation to provide rapid dynamic acquisitions. However, the resulting data is angularly undersampled, due to the limited number of views. We propose a novel reconstruction algorithm for sparse-view SPECT based on Compressed Sensing (CS) theory. The algorithm models Poisson noise by modifying the Iterative Hard Thresholding algorithm to minimize the Kullback-Leibler (KL) distance by gradient descent. Because the underlying objects of SPECT images are expected to be smooth, a discrete wavelet transform (DWT) using an orthogonal spline wavelet kernel is used as the sparsifying transform. Preliminary feasibility of the algorithm was tested on simulated data of a phantom consisting of two Gaussian distributions. Single-pinhole projection data with Poisson noise were simulated at 128, 60, 15, 10, and 5 views over 360 degrees. Image quality was assessed using the coefficient of variation and the relative contrast between the two objects in the phantom. Overall, the results demonstrate preliminary feasibility of the proposed CS algorithm for sparse-view SPECT imaging

Write Channel Model for Bit-Patterned Media Recording

We propose a new write channel model for bit-patterned media recording that reflects the data dependence of write synchronization errors. It is shown that this model accommodates both substitution-like errors and insertion-deletion errors whose statistics are determined by an underlying channel state process. We study information theoretic properties of the write channel model, including the capacity, symmetric information rate, Markov-1 rate and the zero-error capacity.Comment: 11 pages, 12 figures, journa

A spatial panel approach to the east German wage curve

This study presents results about wage effects of unemployment in eastern Germany. The standard approach to analyse the wage curve takes no account of the spatial relationship among regions. Ignoring this relationship may seriously bias the results. To investigate this, the East German wage curve is estimated including spatial effects using panel data classified into 114 administrative districts over the period 1993-1999. It extends the analysis of Baltagi, Blien and Wolf (2000) in which spatial effects were not taken into account. To control for the possible endogeneity of the unemployment rate, one of the explanatory variables, instrumental variable methods should be used. To control for spatial dependence, this paper adopts the use of matrix exponentials for spatially transforming the error terms. This transformation has the advantage that the Jacobian term equals zero. Two important empirical results appear. If spatial effects are not taken into account, the unemployment elasticity in Eastern Germany is larger than in Western countries. If spatial effects are added, the unemployment elasticity significantly reduces.

Determination of Optimum Harvest Date for Winter Malting Quality Barley in Northwest Arkansas

Due to the strict quality requirements, only 10 percent of worldwide barley is used for malting, though malting quality barley comes with a price increase of up to 50 percent or higher. With the craft brewery industry growing in Northwest Arkansas there is a growing demand for locally sourced malt quality barley. However, data is lacking regarding production practices for barley in Arkansas. The optimum harvest date for malting quality barley is at physiological maturity. This is because many of the malting traits (such as germination energy) decline as harvest is delayed, which will make it difficult to meet the criteria for malting quality if the barley is left in the field. The purpose of this study was to evaluate the effects of harvest date on the malting quality of barley grown in Northwest Arkansas, specifically, the effect of harvest date on barley seed quality characteristics that impact malting and the interaction of harvest date and cultivar. Harvest date, cultivar, and in many cases the interaction of harvest date and cultivar were significant for grain yield, test weight, water sensitivity, germination energy, and germination capacity. There was no significant variation between cultivars for protein content. In general, all malting quality traits decreased with delayed harvest and the decrease at 21 days after physiological maturity was statistically significantly. Of the cultivars tested Thoroughbred was closest to meeting the criteria for malting quality, having the highest grain yield, while maintaining germination energy and capacity into a later harvest date