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Auditory Spectrum-Based Pitched Instrument Onset Detection
In this paper, a method for onset detection of music signals using auditory spectra is proposed. The auditory spectrogram provides a time-frequency representation that employs a sound processing model resembling the human auditory system. Recent work on onset detection employs DFT-based features describing spectral energy and phase differences, as well as pitch-based features. These features are often combined for maximizing detection performance. Here, the spectral flux and phase slope features are derived in the auditory framework and a novel fundamental frequency estimation algorithm based on auditory spectra is introduced. An onset detection algorithm is proposed, which processes and combines the aforementioned features at the decision level. Experiments are conducted on a dataset covering 11 pitched instrument types, consisting of 1829 onsets in total. Results indicate that auditory representations outperform various state-of-the-art approaches, with the onset detection algorithm reaching an F-measure of 82.6%
Camera Surveillance as a Measure of Counterterrorism?
Camera surveillance has recently gained prominence in policy proposals on combating terrorism. We evaluate this instrument of counterterrorism as resting on the premise of a deterrence effect. Based on comparative arguments and previous evidence on crime, we expect camera surveillance to have a relatively smaller deterrent effect on terrorism than on other forms of crime. In particular, we emphasize opportunities for substitution (i.e., displacement effects), the interaction with media attention aspired to by terrorists, the limits of real-time interventions, the crowding-out of social surveillance, the risk of misguided profiling, and politico-economic concerns regarding the misuse of the technology.Camera surveillance, closed-circuit television (CCTV), public security, deterrence, terrorism.
Sir Henry Thomas De la Beche and the founding of the British Geological Survey
The founding of the Geological Survey by Henry De la Beche in 1835 is a key event in the history of British geology. Yet the Survey’s initiation actually began three years earlier when De la Beche secured financial assistance from the Board of Ordnance to map the geology of Devon at a scale of one inch to the mile. The British Geological Survey has thus been in existence for at least 175 years and can justly claim to be the world’s oldest continuously functioning geological survey organisation. There were early government-funded geological surveys also in France, the United States, Ireland and Scotland. De la Beche’s notable success both in launching and sustaining the Geological Survey demanded a good deal of diplomacy, determination and deviousness! Even so, the Survey was nearly brought to an untimely end in 1837 when De la Beche was publicly criticised for his interpretation, based on lithology and field relations, of the difficult Culm strata of north Devon. The resolution of the ‘Devonian Controversy’ led to a fundamental change in geological practice, in which the value of fossils as stratigraphic markers, founded on an acceptance of organic change over time, was established beyond question. Fortunately the Survey survived its early trauma and De la Beche went on to extend his influence with the expansion of the Museum of Economic Geology (also formed in 1835), and the establishment of the Mining Record Office and the School of Mines
Variations of the McEliece Cryptosystem
Two variations of the McEliece cryptosystem are presented. The first one is
based on a relaxation of the column permutation in the classical McEliece
scrambling process. This is done in such a way that the Hamming weight of the
error, added in the encryption process, can be controlled so that efficient
decryption remains possible. The second variation is based on the use of
spatially coupled moderate-density parity-check codes as secret codes. These
codes are known for their excellent error-correction performance and allow for
a relatively low key size in the cryptosystem. For both variants the security
with respect to known attacks is discussed
Anticholinergic therapy for acute asthma in children.
Inhaled anticholinergics as single agent bronchodilators (or in combination with beta(2)-agonists) are one of the several medications available for the treatment of acute asthma in children
Prisoners of War as Library Users
One does not usually associate libraries and study classes with amenities provided for internees in Prisoner of War camps in the First World War. It was surprising then for me, as Librarian/Archivist of the Canadian War Museum, to find evidence in our Library/Archives of well-organized libraries in the First World War internment camps in Germany. My introduction to POW library users in this war came about as I was undertaking a preliminary inventory of the rich resources of the Canadian War Museum (CWM) Archives. In the CWM Archives are two files related to libraries in POW camps in Germany. One file (Accession 19800077) holds letters from 2nd Lieutenant Archibald Campbell, a Canadian, sent to his parents from his POW camp in Germany. The other file (Accession 19710056) contains information on officially sanctioned libraries in German POW camps.
These discoveries provoked the initial interest and prompted me to see as an experiment what else could be found to flesh out this theme amongst the resources contained in the CWM’s archives and library. The results were sufficiently interesting, not only for demonstrating the potential of our archives/library but in elucidating this hitherto neglected theme in First World War history, as to merit being brought to the attention of the readership of this journal
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