Oscillatory Properties of Solutions of the Fourth Order Difference Equations with Quasidifferences

A class of fourth--order neutral type difference equations with quasidifferences and deviating arguments is considered. Our approach is based on studying the considered equation as a system of a four--dimensional difference system. The sufficient conditions under which the considered equation has no quickly oscillatory solutions are given

Music Piracy and Its Criminalization: Understanding the Napster Era (1999) to Present Through Donald Black\u27s Theory of Moral Time

In the year 1999 Napster, a provider of music downloading software, broke news headlines around the world when copyright infringement lawsuits were filed against the company. Ever since then internet music piracy has been a very controversial topic and a target for criminalization efforts. In the field of criminology there have been few attempts to apply theory to the topic of internet music piracy. Theorization of internet music piracy has mainly focused on the illegal behavior of music piracy, explaining the motivations and knowledge behind it. Something that has been neglected in theoretical work of online music piracy is its criminalization. This thesis topic is significant in that it is a theoretical application test of Donald Black\u27s newest theory, Moral Time. Black, a sociologist from the University of Virginia, who is well known for his works The Behavior of Law and Sociological Justice introduced this new theory in 2011. The Moral Time theory is a theory of why conflicts occur and why some conflicts are worse than others. Using this theory, four key stages of criminalization efforts taken by the music industry are examined and elaborated upon as a means to identify why the music industry chose to take the actions it did against online music piracy

Cascaded half-harmonic generation of femtosecond frequency combs in mid-IR

For the growing demand of frequency combs in mid-infrared (mid-IR), known as the "molecular fingerprint" region of the spectrum [1], down conversion of near-IR frequency combs through half- harmonic generation offers numerous benefits including high conversion efficiency and intrinsic phase and frequency locking to the near-IR pump [2]. Hence cascaded half-harmonic generation promises a simple path towards extending the wavelength coverage of stable frequency combs. Here, we report a two-octave down-conversion of a frequency comb around 1 {\mu}m through cascaded half-harmonic generation with ~64% efficiency in the first stage, and ~18% in the second stage. We obtain broadband intrinsically-frequency-locked frequency combs with ~50-fs pulses at ~2 {\mu}m and ~110-fs pulses at ~4 {\mu}m. These results indicate the effectiveness of half-harmonic generation as a universal tool for efficient phase- and frequency-locked down-conversion, which can be beneficial for numerous applications requiring long-wavelength coherent sources

Experimental study of the effect of vertical acceleration component on the slope stability

The paper deals with the stability of earth dams subjected to seismic and paraseismic excitations occurring in the close distance to the dam. The Newmark’s stability approach, classified as a simplified dynamic method, has been extended for two directional dynamic loading case and the evolution of the friction coefficient. The paper is focused on the experimental verification of the proposed method for harmonic and cyclic excitations generated by a simple oscillating device as well as by one-directional shaking table. Main assumptions of the proposed method have been proved and the effect of the vertical acceleration on the stability of the dam has been demonstrated. In the experiments conducted under cyclic loading, the impact of the vertical acceleration on the permanent displacement of the block was equal to 57 %. However, in general, the exact magnitude of this impact depends on many factors, such as the vertical to horizontal peak ground acceleration ratio or frequency range of the vertical component of the earthquake

Determining crucial factors for the popularity of scientific articles

Using a set of over 70.000 records from PLOS One journal consisting of 37 lexical, sentiment and bibliographic variables we perform analysis backed with machine learning methods to predict the class of popularity of scientific papers defined by the number of times they have been viewed. Our study shows correlations among the features and recovers a threshold for the number of views that results in the best prediction results in terms of Matthew's correlation coefficient. Moreover, by creating a variable importance plot for random forest classifier, we are able to reduce the number of features while keeping similar predictability and determine crucial factors responsible for the popularity.Comment: 13 pages, 6 figure