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991.
Grewe Oliver; Nagel Frederik; Kopiez Reinhard; Altenmüller Eckart 《Canadian Metallurgical Quarterly》2007,7(4):774
Most people are able to identify basic emotions expressed in music and experience affective reactions to music. But does music generally induce emotion? Does it elicit subjective feelings, physiological arousal, and motor reactions reliably in different individuals? In this interdisciplinary study, measurement of skin conductance, facial muscle activity, and self-monitoring were synchronized with musical stimuli. A group of 38 participants listened to classical, rock, and pop music and reported their feelings in a two-dimensional emotion space during listening. The first entrance of a solo voice or choir and the beginning of new sections were found to elicit interindividual changes in subjective feelings and physiological arousal. Quincy Jones' "Bossa Nova" motivated movement and laughing in more than half of the participants. Bodily reactions such as "goose bumps" and "shivers" could be stimulated by the "Tuba Mirum" from Mozart's Requiem in 7 of 38 participants. In addition, the authors repeated the experiment seven times with one participant to examine intraindividual stability of effects. This exploratory combination of approaches throws a new light on the astonishing complexity of affective music listening. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Noam Berger Béla Bollobás Christian Borgs Jennifer Chayes Oliver Riordan 《Theoretical computer science》2007
Power laws, in particular power-law degree distributions, have been observed in real-world networks in a very wide range of contexts, including social networks, biological networks, and artificial networks such as the physical internet or abstract world wide web. Recently, these observations have triggered much work attempting to explain the power laws in terms of new ‘scale-free’ random graph models. So far, perhaps the most effective mechanism for explaining power laws is the combination of growth and preferential attachment. In [A. Fabrikant, E. Koutsoupias, C.H. Papadimitriou, Heuristically optimized trade-offs: A new paradigm for power laws in the internet ICALP 2002, in: LNCS, vol. 2380, pp. 110–122], Fabrikant, Koutsoupias and Papadimitriou propose a new ‘paradigm’ for explaining power laws, based on trade-offs between competing objectives. They also introduce a new, simple and elegant parametrized model for the internet, and prove some kind of power-law bound on the degree sequence for a wide range of scalings of the trade-off parameter. 相似文献
993.
The study was carried out to gain information about the availability and the accessibility of dental services to adults with physical disabilities in Gateshead, an industrial town with a population of 199,588 situated in northeast England. Questionnaires were sent to all general dental practices to ascertain the dental staff's perceptions of the accessibility of their premises, their willingness to treat people with disabilities, and the types of treatment offered. The main problem for access was caused by stairs and other physical barriers within buildings. Lack of portable equipment limited the scope of domiciliary treatment offered. 相似文献
994.
Zusammenfassung Die Forderung von Microsoft nach einem einheitlichen Datenschutzrecht in den USA auf Bundesebene hat viele hier in Deutschland
überrascht. Ein Gezeitenwechsel ausgerechnet in den zun?chst auf Marktmechanismen setzenden USA? ... und dann noch von Microsoft,
einem Unternehmen, dessen de facto Standard schon fast selbst Gesetzeskraft zukommt. Die Motive und Hintergründe kl?ren in
diesem Beitrag Axel Spies und Oliver Stutz auf. 相似文献
995.
Lindemann Oliver; Abolafia Juan M.; Girardi Giovanna; Bekkering Harold 《Canadian Metallurgical Quarterly》2007,33(6):1400
To investigate the functional connection between numerical cognition and action planning, the authors required participants to perform different grasping responses depending on the parity status of Arabic digits. The results show that precision grip actions were initiated faster in response to small numbers, whereas power grips were initiated faster in response to large numbers. Moreover, analyses of the grasping kinematics reveal an enlarged maximum grip aperture in the presence of large numbers. Reaction time effects remained present when controlling for the number of fingers used while grasping but disappeared when participants pointed to the object. The data indicate a priming of size-related motor features by numerals and support the idea that representations of numbers and actions share common cognitive codes within a generalized magnitude system. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
Axel Klawonn Oliver Rheinbach 《Computer Methods in Applied Mechanics and Engineering》2007,196(8):1400-1414
Iterative substructuring methods with Lagrange multipliers are considered for heterogeneous linear elasticity problems with large discontinuities in the material stiffnesses. In particular, results for algorithms belonging to the family of dual-primal FETI methods are presented. The core issue of these algorithms is the construction of an appropriate global problem, in order to obtain a robust method which converges independently of the material discontinuities. In this article, several necessary and sufficient conditions arising from the theory are numerically tested and confirmed. Furthermore, results of numerical experiments are presented for situations which are not covered by the theory, such as curved edges and material discontinuities not aligned with the interface, and an attempt is made to develop rules for these cases. 相似文献
997.
A core construct in socioemotional selectivity theory is future time perspective (FTP), conceptualized as a unidimensional and bipolar construct ranging from expansive to limited. Change in FTP across adulthood has been treated as linear, with older adults showing more limited FTP. Studies 1 and 2 showed that a 2-factor model fit better, with focus on opportunities and focus on limitations as distinct dimensions. These dimensions changed differentially with age. In cross-sectional Study 3, focus on opportunities was higher in young adulthood than in early middle age but did not drop further in late middle age. Focus on limitations was the same in young adulthood and early middle age but was higher in late middle age. In longitudinal Study 4, focus on limitations increased from early to late middle age, and focus on opportunities was again maintained, rather than showing the decrease one would assume from a 1-factor model of FTP. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
Varying bending eigenfrequencies in BTA deep hole drilling: mechanical modeling using statistical parameter estimation 总被引:1,自引:1,他引:0
One serious problem in deep-hole drilling is the formation of a dynamic disturbance called spiralling which causes a multi-lobe
shaped distortion of the bore hole cross section. An important factor governing the occurrence of spiralling is the coincidence
of a bending eigenfrequency of the boring tool with a multiple of the spindle rotation frequency. This article presents a
discrete dynamic model of the tool/boring-bar assembly including a Lanchester-damper and containing free parameters for the
unknown stiffness of the tools lateral supports. Furthermore, a method for estimating these parameters by determining the
changing eigenfrequencies over the drilling depth from spectrogram data using the maximum likelihood method is proposed.
The work presented in this paper is financially supported by the ‘Deutsche Forschungsgemeinschaft (DFG)’ within the ‘Sonderforschungs-bereich
(SFB)’ 475. It is conducted in cooperation with Lehrstuhl Computergestützte Statistik, University of Dortmund. 相似文献
999.
AM Nouri RF Hussain AV Dos Santos M Mansouri RT Oliver 《Canadian Metallurgical Quarterly》1993,67(6):1223-1228
A modified tetrazolium reduction assay (MTT) was used to assess the relation between HLA class I antigen expression on tumour cells and their susceptibility as a target for non-MHC restricted LAK/NK cytotoxicity using interleukin-2 activated peripheral blood mononuclear cells (MNC) from normal individuals. At 20/1 effector/target ratio this ranged from no killing to 77%. The efficiency of killing was dependent on duration of effector cell culture with IL-2, peaking at day 10 and declining thereafter. This killing could be enhanced by addition of other cytokines including interferons alpha, beta and gamma. Study of a panel of 15 tumour cell lines using a single effector showed that there was no statistically significant inverse correlation (using Spearman rank test) between the degree of tumour class I expression and LAK/NK killing at 20/1 (r = 0.23 P = 0.39) and 10/1 (r = 0.30, P = 0.27) and at 5/1 E/T ratio r = 0.47, P = 0.08) respectively. Lack of inverse correlation between these two parameters came from study of one bladder tumour line (FEN), whose absent class I antigens had been corrected by transfection with beta 2 microglobulin gene. At high E/T ratio (20/1) there was an increase in the susceptibility of target cells to lysis (36% parent cell, 45% transfected cell), whilst at lower E/T ratios (1/1) there was significantly more killing of the non-transfected cells (10% vs 31%). The addition of anti-class I antibody W6/32 increased killing by 18% but this was non-specific as the same increase occurred with a class II antibody. These data suggest that overall there was not an inverse correlation between class I expression and LAK/NK killing at high E/T ratios, whilst at low (5/1 or lower) E/T ratios this correlation nearly reached statistical significance suggesting that the conflicting literature reports may be due to a threshold levels of effector cells above which the masking effects of MHC antigens disappears. 相似文献
1000.