928 resultados para Influence of the temperature
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Virtual reality has a number of advantages for analyzing sports interactions such as the standardization of experimental conditions, stereoscopic vision, and complete control of animated humanoid movement. Nevertheless, in order to be useful for sports applications, accurate perception of simulated movement in the virtual sports environment is essential. This perception depends on parameters of the synthetic character such as the number of degrees of freedom of its skeleton or the levels of detail (LOD) of its graphical representation. This study focuses on the influence of this latter parameter on the perception of the movement. In order to evaluate it, this study analyzes the judgments of immersed handball goalkeepers that play against a graphically modified virtual thrower. Five graphical representations of the throwing action were defined: a textured reference level (L0), a nontextured level (L1), a wire-frame level (L2), a moving point light display (MLD) level with a normal-sized ball (L3), and a MLD level where the ball is represented by a point of light (L4). The results show that judgments made by goalkeepers in the L4 condition are significantly less accurate than in all the other conditions (p
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Background: In this paper we investigate the definition and formation of financial networks. Specifically, we study the influence of the time scale on their construction.
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Rural support organisations have emerged since agricultural restructuring of the 1980s. The paper draws on research from the UK and Canada to suggest that the support in both countries is derived from a patrilineal culture that still dominates family farming. The paper begins by outlining a conceptual basis for arguing that such a culture can be understood as comprising of male and female relational gender identities capable of explaining farm relationships, farm survival and adjustment strategies and community engagement. These components, it is argued, are facets of the patrilineal farming culture which must be understood if its impacts on all its members are to be appropriately comprehended and supported.
The paper has two key aims, therefore. Firstly it suggests that a more nuanced understanding of farming „culture? which is persistently patrilineal in nature is now required which is capable of addressing the realities of farming individuals?
lives as they perceive them. The conceptualisation of such a culture is informed
by drawing on insights from gender theory, agricultural geography and rural studies. This conceptual discussion provides the context for the paper?s second aim which is to demonstrate how rural support in both the UK and Canada is derived „from? and is influenced by such a patrilineal culture . Findings are
presented identifying five key themes from this conceptualization which influence the support of such organisations. Thus, it is suggested, that the nature of rural support can be better understood and the appropriateness of the support interrogated when such conceptualization is taken on board.
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This paper presents studies on the properties of fresh and hardened semilightweight self-consolidating concrete (SLWSCC) mixtures, produced with two types of manufactured coarse lightweight aggregates (LWA) and normal weight sand. The first type, a sintered pulverized fuel ash, was made from an industrial by-product, fly ash, whereas the second one, an expanded clay, was produced from a naturally sourced clay. For all mixtures, normal weight sand was used as a fine fraction of aggregates, and the portland cement was partially replaced with a limestone powder. The SLWSCC was produced with different water presaturation regimes of the LWAs. The desired initial slump-flow spread was set between 700 and 800 mm. The effect of three superplasticizers was evaluated by testing properties of SLWSCC, normal weight SCC, and paste mixtures. Three SCC fresh properties were measured: the slump-flow, the V-funnel flow time, and the J-ring blocking step. Moreover, the slump-flow loss was evaluated. The degree of segregation was assessed in both fresh and hardened states. Additionally, the hardened density and the compressive strengths were tested. All SLWSCC mixtures were produced with a desired range of slump-flow spread and with satisfactory passing ability assessed with the J-ring test. SLWSCCs prepared with the expanded clay LWA were less sensitive to the variation of water presaturation levels and showed lower viscosity than those made with the sintered pulverized fuel ash LWA. Only mixtures containing SP-3 superplasticizer showed acceptable workability loss resistance. The saturated surface-dry density of all of the mixtures varied in a range of 2,025–2,125??kg/m 3 . Mixtures containing 29% of coarse LWAs and 71% of sand (by mass) had 24-h and 28-day compressive strengths above 20 and 40 MPa, respectively, but the mixtures made with the expanded clay were slightly weaker.
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Evidence of 11-year Schwabe solar sunspot cycles, El Niño-Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO) were detected in an annual record of diatomaceous laminated sediments from anoxic Effingham Inlet, Vancouver Island, British Columbia. Radiometric dating and counting of annual varves dates the sediments from AD 1947-1993. Intact sediment slabs were X-rayed for sediment structure (lamina thickness and composition based on gray-scale), and subsamples were examined for diatom abundances and for grain size. Wavelet analysis reveals the presence of ~2-3, ~4.5, ~7 and ~9-12-year cycles in the diatom record and an w11e13 year record in the sedimentary varve thickness record. These cycle lengths suggest that both ENSO and the sunspot cycle had an influence on primary productivity and sedimentation patterns. Sediment grain size could not be correlated to the sunspot cycle although a peak in the grain size data centered around the mid-1970s may be related to the 1976-1977 Pacific climate shift, which occurred when the PDO index shifted from negative (cool conditions) to positive (warm conditions). Additional evidence of the PDO regime shift is found in wavelet and cross-wavelet results for Skeletonema costatum, a weakly silicified variant of S. costatum, annual precipitation and April to June precipitation. Higher spring (April/May) values of the North Pacific High pressure index during sunspot minima suggest that during this time, increased cloud cover and concomitant suppression of the Aleutian Low (AL) pressure system led to strengthened coastal upwelling and enhanced diatom production earlier in the year. These results suggest that the 11-year solar cycle, amplified by cloud cover and upwelling changes, as well as ENSO, exert significant influence on marine primary productivity in the northeast Pacific. The expression of these cyclic phenomena in the sedimentary record were in turn modulated by the phase of PDO, as indicated by the change in period of ENSO and suppression of the solar signal in the record after the 1976-1977 regime shift. © 2013 Elsevier Ltd and INQUA. All rights reserved.
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Purpose: To assess the quality of referrals from community optometrists in the northeast of Scotland to the hospital glaucoma service before and after the implementation of the new General Ophthalmic Services (GOS) contract in Scotland. Methods: Retrospective study encompassing two 6-month periods, one before the implementation of the new GOS (Scotland) contract in April 2006 (from June to November 2005), and the other after (from June to November 2006). The community optometrist referral forms and hospital glaucoma service notes were reviewed. Comparisons were performed using the t-test and ?- test. Results: In all, 183 referrals were made during the first 6-month period from June to November 2005, and 120 referrals were made during the second 6-month period from June to November 2006. After the introduction of the new GOS contract, there was a statistically significant increase in true-positive referrals (from 18.0 to 31.7%; P=0.006), decrease in false-positive referrals (from 36.6 to 31.7%; P=0.006), and increase in the number of referrals with information on applanation tonometry (from 11.8 to 50.0%; P=0.000), dilated fundal examination (from 2.2 to 24.2%; P=0.000), and repeat visual fields (from 14.8 to 28.3%; P=0.004) when compared to the first 6-month period. However, only 41.7% of referrals fulfilled the new GOS contract requirements, with information on applanation tonometry the most commonly missing. Conclusions: After the implementation of the new GOS (Scotland) contract in April 2006, there has been an improvement in the quality of the glaucoma referrals from the community optometrists in the northeast of Scotland, with a corresponding reduction in false-positive referrals. Despite the relatively positive effect so far, there is still scope for further improvement. © 2009 Macmillan Publishers Limited All rights reserved.
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The inference of gene regulatory networks gained within recent years a considerable interest in the biology and biomedical community. The purpose of this paper is to investigate the influence that environmental conditions can exhibit on the inference performance of network inference algorithms. Specifically, we study five network inference methods, Aracne, BC3NET, CLR, C3NET and MRNET, and compare the results for three different conditions: (I) observational gene expression data: normal environmental condition, (II) interventional gene expression data: growth in rich media, (III) interventional gene expression data: normal environmental condition interrupted by a positive spike-in stimulation. Overall, we find that different statistical inference methods lead to comparable, but condition-specific results. Further, our results suggest that non-steady-state data enhance the inferability of regulatory networks.
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We use images of high spatial and temporal resolution, obtained using both ground- and space-based instrumentation, to investigate the role magnetic field inclination angles play in the propagation characteristics of running penumbral waves in the solar chromosphere. Analysis of a near-circular sunspot, close to the center of the solar disk, reveals a smooth rise in oscillatory period as a function of distance from the umbral barycenter. However, in one directional quadrant, corresponding to the north direction, a pronounced kink in the period-distance diagram is found. Utilizing a combination of the inversion of magnetic Stokes vectors and force-free field extrapolations, we attribute this behavior to the cut-off frequency imposed by the magnetic field geometry in this location. A rapid, localized inclination of the magnetic field lines in the north direction results in a faster increase in the dominant periodicity due to an accelerated reduction in the cut-off frequency. For the first time, we reveal how the spatial distribution of dominant wave periods, obtained with one of the highest resolution solar instruments currently available, directly reflects the magnetic geometry of the underlying sunspot, thus opening up a wealth of possibilities in future magnetohydrodynamic seismology studies. In addition, the intrinsic relationships we find between the underlying magnetic field geometries connecting the photosphere to the chromosphere, and the characteristics of running penumbral waves observed in the upper chromosphere, directly supports the interpretation that running penumbral wave phenomena are the chromospheric signature of upwardly propagating magneto-acoustic waves generated in the photosphere.
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We investigate whether the presence of a human body in wearable communications should be considered as part of the radiating structure or as part of the local radio environment. The Rician $K$ -factor was employed as a quantitative measure of the effect of the user's body for five environments and two mounting locations. Presented empirical results indicated that the environment had a greater impact on the $K$-factor values than the position of the transmit antenna for the ultrawideband signals used, confirming that the human body should be considered primarily as part of the overall radiating system when the antenna is worn on the body. Furthermore, independent variations also existed in the $K$-factor values for the differing antenna-body mounting positions, indicating that as the position changed, then the radiating effects and the contribution from the body changed. This is significant for ensuring body-antenna systems are accurately modeled in system-level simulations.