9,745 research outputs found
Investigation of Noise Field and Velocity Profiles of an Afterburning Engine
Sound pressure levels, frequency spectrum, and jet velocity profiles are presented for an engine-afterburner combination at various values of afterburner fuel - air ratio. At the high fuel-air ratios, severe low-frequency resonance was encountered which represented more than half the total energy in the sound spectrum. At similar thrust conditions, lower sound pressure levels were obtained from a current fighter air craft with a different afterburner configuration. The lower sound pressure levels are attributed to resonance-free afterburner operation and thereby indicate the importance of acoustic considerations in afterburner design
Oviposition Preference of the Mimosa Webworm, Homadaula anisocentra (Lepidoptera: Plutellidae)
In the field, the mimosa webworm, Homadaula anisocentra Meyrick (Lepidoptera: Plutellidae), oviposits preferentially on branches or on leaf rachises or petioles of uninfested ornamental honeylocust, Gleditsia triacanthos L. On infested trees, oviposition occurs almost entirely on larval webbing. In the laboratory, uninfested mature leaves of both honeylocust and mimosa, Albizzia julibrissin Durazzini, are preferred over uninfested young leaves as oviposition sites. The addition of larval webbing to leaves of any age or to nonhost substrate induces oviposition preferentially on the webbin
Collaboration, cognitive effort, and self-reference in United Kingdom top 5 pop music lyrics 1960–2015
This research investigated associations between the lyrics of every song to have reached the weekly U.K. Top 5 singles chart from 1960 to 2015 and the number of people responsible for recording each song. Following computerized content analysis of the lyrics of the 4,534 unique songs, the results showed that the number of musicians involved was negatively related to use of cognitive terms, consistent with previous research on social loafing, and was also negatively related to instances of self-reference and use of language concerning social interaction, arguably in reflection of the inherent constraints on such that arise from collaborating with others
Does rotation of B stars depend on metallicity? preliminary results from GIRAFFE spectra
We show the vsini distribution of main sequence B stars in sites of various
metallicities, in the absolute magnitude range -3.34 < Mv < -2.17. These
include Galactic stars in the field measured by Abt et al. (2002), members of
the h & chi Per open clusters measured by North et al. (2004), and five fields
in the SMC and LMC measured at ESO Paranal with the FLAMES-GIRAFFE
spectrograph, within the Geneva-Lausanne guaranteed time. Following the
suggestion by Maeder et al. (1999), we do find a higher rate of rapid rotators
in the Magellanic Clouds than in the Galaxy, but the vsini distribution is the
same in the LMC and in the SMC in spite of their very different metallicities.Comment: 2 pages, 1 figure, poster presented at the ESO/Arcetri Workshop on
"Chemical abundances and mixing in stars in the Milky Way and its
satellites", 13-17 Sept. 200
Popular music lyrics and the COVID-19 pandemic
A limited amount of previous research suggests that deteriorating socioeconomic conditions may be associated with greater popularity of music lyrics featuring negative emotional content and references to relationships. The present research considered this in charting popular music before and during the first six months of the COVID-19 pandemic. A dataset based on the song lyrics of the top-5 charting weekly songs in the UK and USA from January 1999 to August 2020 was computer-analysed for interpersonal variables, such as satisfaction and human interest, and positive and negative emotional valence. Results indicated lower satisfaction and human interest in lyrics in the USA and UK in the first six months of the COVID-19 pandemic compared to the lyrics in charting songs in 2015-2019. The USA charting songs in 2020 also saw higher leveling and negative emotional content; and, when considering monthly data from 1999-2020, there was a positive association between economic misery and the number of negatively-valenced words. The findings broaden our understanding of the relationship between significant global events and trends in popular music
Can music move people? : The effects of musical complexity and silence on waiting time
Previous research has suggested that music might influence the amount of time for which people are prepared to wait in a given environment. In an attempt to investigate the mechanisms underlying such effects, this study employed three levels of musical complexity and also a “no-music” condition. While one of these played in the background, participants were left to wait in a laboratory for the supposed start of an experiment. The results indicated that participants waited for the least amount of time during the no-music condition, and that there were no differences between the three music conditions. Other evidence indicated that this may be attributable to the music distracting participants’ attention from an internal timing mechanism. The results are discussed in terms of their implications for consumer behavior and research on the psychology of everyday life
Parenting style as a predictor of music preference
Although previous research has established relationships between perceived parenting styles and
children’s deviant behaviours and links between these behaviours and a liking for intense and
rebellious music, no research has explored the associations between perceived parenting styles and
children’s liking for different music styles. Whereas previous research has considered musical taste
by looking at a small number of individual difference variables in isolation from one another, the
present research used a cross-sectional correlational design to investigate whether parenting styles,
the Big Five personality traits, sensation seeking, age, and gender were associated with a liking
for different music styles. In total, 336 Australians completed an online, self-report questionnaire.
Analyses demonstrated there were relationships between five of the six parenting style variables and
five of the music styles considered. This indicates that various parenting styles were associated with
musical taste, and the nature of these associations extends well beyond those concerning rebellious
music and neglectful parenting that have been identified by previous research
Vegetation height products between 60° S and 60° N from ICESat GLAS data.
We present new coarse resolution (0.5� ×0.5�)vegetation height and vegetation-cover fraction data sets between
60� S and 60� N for use in climate models and ecological
models. The data sets are derived from 2003–2009 measurements collected by the Geoscience Laser Altimeter System (GLAS) on the Ice, Cloud and land Elevation Satellite (ICESat), the only LiDAR instrument that provides close to global coverage. Initial vegetation height is calculated from GLAS data using a development of the model of Rosette et al. (2008) with further calibration on desert sites. Filters are developed to identify and eliminate spurious observations in the GLAS data, e.g. data that are affected by clouds, atmosphere
and terrain and as such result in erroneous estimates
of vegetation height or vegetation cover. Filtered GLAS vegetation height estimates are aggregated in histograms from 0 to 70m in 0.5m intervals for each 0.5�×0.5�. The GLAS vegetation height product is evaluated in four ways. Firstly, the Vegetation height data and data filters are evaluated using aircraft LiDAR measurements of the same for ten sites in the Americas, Europe, and Australia. Application of filters to the GLAS vegetation height estimates increases the correlation with aircraft data from r =0.33 to r =0.78, decreases the root-mean-square error by a factor 3 to about 6m (RMSE) or 4.5m (68% error distribution) and decreases the bias from 5.7m to −1.3 m. Secondly, the global aggregated GLAS vegetation height product is tested for sensitivity towards the choice of data quality filters; areas with frequent cloud cover and areas with steep terrain are the most sensitive to the choice of thresholds for the filters. The changes in height estimates by applying different filters are, for the main part, smaller than the overall uncertainty of 4.5–6m established from the site measurements. Thirdly, the GLAS global vegetation height product is compared with a global vegetation height product typically used in a climate model, a recent global tree height product, and a vegetation greenness product and is shown to produce realistic estimates of vegetation height. Finally, the GLAS bare soil cover fraction is compared globally with the MODIS bare soil fraction (r = 0.65) and with bare soil cover fraction estimates derived from AVHRR NDVI data (r =0.67); the GLAS treecover fraction is compared with the MODIS tree-cover fraction (r =0.79). The evaluation indicates that filters applied to the GLAS data are conservative and eliminate a large proportion of spurious data, while only in a minority of cases at the cost of removing reliable data as well. The new GLAS vegetation height product appears more realistic than previous data sets used in climate models and ecological models and hence should significantly improve simulations that involve the land surface
Popular music lyrics and musicians’ gender over time: A computational approach
The present study investigated how the gender distribution of the United Kingdom’s most popular artists has changed over time and the extent to which these changes might relate to popular music lyrics. Using data mining and machine learning techniques, we analyzed all songs that reached the UK weekly top 5 sales charts from 1960 to 2015 (4,222 songs). DICTION software facilitated a computerized analysis of the lyrics, measuring a total of 36 lyrical variables per song. Results showed a significant inequality in gender representation on the charts. However, the presence of female musicians increased significantly over the time span. The most critical inflection points leading to changes in the prevalence of female musicians were in 1968, 1976, and 1984. Linear mixed-effect models showed that the total number of words and the use of self-reference in popular music lyrics changed significantly as a function of musicians’ gender distribution over time, and particularly around the three critical inflection points identified. Irrespective of gender, there was a significant trend toward increasing repetition in the lyrics over time. Results are discussed in terms of the potential advantages of using machine learning techniques to study naturalistic singles sales charts data
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