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Bob L. Sturm 《Journal of Intelligent Information Systems》2013,41(3):371-406
We argue that an evaluation of system behavior at the level of the music is required to usefully address the fundamental problems of music genre recognition (MGR), and indeed other tasks of music information retrieval, such as autotagging. A recent review of works in MGR since 1995 shows that most (82 %) measure the capacity of a system to recognize genre by its classification accuracy. After reviewing evaluation in MGR, we show that neither classification accuracy, nor recall and precision, nor confusion tables, necessarily reflect the capacity of a system to recognize genre in musical signals. Hence, such figures of merit cannot be used to reliably rank, promote or discount the genre recognition performance of MGR systems if genre recognition (rather than identification by irrelevant confounding factors) is the objective. This motivates the development of a richer experimental toolbox for evaluating any system designed to intelligently extract information from music signals. 相似文献
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T. Ohde Corresponding author B. Sturm H. Siegel 《International journal of remote sensing》2013,34(7-8):1495-1499
The technique of vicarious calibration is used in connection with an atmospheric correction to improve the Sea viewing Wide Field of view Sensor (SeaWiFS) normalized water-leaving radiance by the first determination of mean vicarious calibration coefficients from in situ measurements in the Baltic Sea. A necessary adjustment of the SeaWiFS pre-flight calibration slope was found to be +3.5%, +0.3%, ?1.7%, ?0.4%, +0.8% and ?1.3% for the first six SeaWiFS channels. The derived mean vicarious calibration coefficients are higher than the coefficients in the standard SeaWiFS Data Analysis System (SeaDAS) software but with similar shape and good agreement with other research results. The coefficients were used to obtain better normalized water-leaving radiance from SeaWiFS measurements in the Baltic Sea. The deviations of calculated to measured radiances in the open Baltic Sea are between 3% and 47% in the channels 412 to 670?nm, with the trend of higher deviations in the blue channels. The objective of radiance determination in all SeaWiFS channels with a maximum uncertainty of 5% in clear water regions is probably not reachable in the turbid water of the Baltic Sea. 相似文献
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NR Srinivas WC Shyu J Lee DS Greene RH Barbhaiya 《Canadian Metallurgical Quarterly》1997,18(7):585-593
An annual atmospheric pollen survey was performed for 14 consecutive years in the autumn at Sakado city, Saitama prefecture. The survey was performed on the transition of pollen dispersion of major allergen plants: ragweed (Ambrosia spp.), Humulus japonicus, Artemisia spp. and Gramineae. 1. Annual total pollen count of ragweed showed marked increases beginning from 1991. Total pollen count in 1991 was 8.8 times and that in 1996 was 18.6 times that in 1983. This increase is probably caused by marked proliferation of giant ragweed which is left without mowing as it is on a dry riverbed, and consequently produces much more pollen than short ragweed. 2. Annual increases in total pollen counts of other major plants which disperse their pollen in the same season as ragweed were 0.95 times in 1991 and 0.5 times in 1996 that in 1983 for Humulus japonicus, 0.68 times in 1991 and 1.5 times in 1996 that in 1983 for Artemisia spp. and 1.3 times in 1991 and 1.4 times in 1996 that in 1983 for Gramineae. None of these species showed a marked increase of pollen dispersion although they showed some annual variation. The above findings suggest that changes in the proliferous state of various allergenic plants due to environmental change should be considered with respect to characteristics of pollen allergy. 相似文献
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NR Moudgal M Jeyakumar HN Krishnamurthy S Sridhar H Krishnamurthy F Martin 《Canadian Metallurgical Quarterly》1997,3(4):335-346
Anti-disialoganglioside (GD2) monoclonal antibodies (MAbs) have been used in vivo for immunolocalization and in phase I and II trials to target disseminated neuroblastoma, the most common extracranial solid tumor in children. However, the efficacy of these first-generation MAbs is likely to be improved by using engineered anti-GD2 antibodies. The generation of single-chain antibody fragments (scFv) could be very helpful as these molecules can be further modified to produce recombinant molecules with pre-defined properties such as immunotoxins, chimeric, or bispecific antibodies. Thus, a scFv directed against GD2 (scFv 7A4) was cloned, sequenced, and expressed. Its binding properties were characterized and compared to that of the parental MAb 7A4. Nucleotide sequence analysis of the scFv 7A4 indicated that its VH region belongs to the V region IIID subgroup and the V kappa to the V region II subgroup. The scFv 7A4 bound to GD2+ neuroblastoma cell lines but not to GD2- cell lines or to GD2- cells isolated from peripheral blood. ELISA and thin-layer chromatography (TLC) indicated that it retained the anti-GD2 specificity, and exhibited a slight cross-reaction with GD3 as the parental MAb. This scFv makes it possible to develop new useful reagents through genetic engineering for adjuvant tumor therapy. 相似文献
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This study examined the role of catastrophizing (i.e. a tendency to exaggerate the threat value of potentially painful situations) in predicting pain experience during dental hygiene treatment. Participants in the research were 100 patients undergoing scaling and/or root planing procedures at Dalhousie University's Dental Clinic. Following treatment, participants completed the Pain Catastrophizing Scale, a measure of emotional distress, a pain scale, and the Dental Anxiety Scale-Revised. Participants who scored above the median on the Pain Catastrophizing Scale were classified as catastrophizers, participants who scored below the median were classified as noncatastrophizers. Results showed that catastrophizers reported significantly more dental anxiety, emotional distress and pain than noncatastrophizers; and that distress reactions were more pronounced in men that in women. Discussion focuses on the importance of addressing psychological factors in dental hygiene practice, particularly as they relate to reactions to dental hygiene procedures, and avoidance of dental care. 相似文献
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NR Every LS Parsons SD Fihn EB Larson C Maynard AP Hallstrom JS Martin WD Weaver 《Canadian Metallurgical Quarterly》1997,96(6):1770-1775
BACKGROUND: Previous studies have documented the strong association between availability of on-site cardiac catheterization facilities and increased use of coronary angiography in patients with acute myocardial infarction (AMI). Although these studies have shown little influence of the availability of catheterization labs on hospital mortality, no long-term follow-up has been reported. METHODS AND RESULTS: From a cohort of 12,331 AMI patients admitted to 19 Seattle area hospitals, we compared long-term outcome in 7985 patients admitted to hospitals with and 4346 patients admitted to hospitals without on-site catheterization labs. During the index hospitalization, patients admitted to hospitals with on-site catheterization were more likely to undergo coronary angiography (67.1% versus 39.3%, P<.0001), coronary angioplasty (32.5% versus 13.2%, P<.0001), or coronary bypass surgery (12.5% versus 9.5%, P<.0001). At 3-year follow-up, patients admitted to hospitals with on-site catheterization labs were more likely to undergo postdischarge angiography (19.2% versus 15.2%, P=.0001) and coronary angioplasty (11.6% versus 8.2%, P<.0001). This was associated with approximately $2500.00 per patient in higher cumulative costs. Despite this higher rate of procedure use, there was no association between admission to a hospital with on-site catheterization facilities and lower long-term mortality (multivariate hazard ratio, 1.0; 95% CI, 0.93 to 1.1., the hazard being associated with admission to hospitals with on-site catheterization facilities). CONCLUSIONS: In an urban area with unconstrained patient transfer mechanisms and high overall cardiac procedure use rates, AMI patients admitted to hospitals without on-site catheterization facilities were managed with fewer procedures during hospitalization and follow-up. This more conservative treatment approach was not associated with any observed increase in long-term mortality. 相似文献