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Arzu Çöltekin Rebecca Francelet Kai-Florian Richter John Thoresen Sara Irina Fabrikant 《制图学和地理信息科学》2018,45(4):339-353
We report on how visual realism might influence map-based route learning performance in a controlled laboratory experiment with 104 male participants in a competitive context. Using animations of a dot moving through routes of interest, we find that participants recall the routes more accurately with abstract road maps than with more realistic satellite maps. We also find that, irrespective of visual realism, participants with higher spatial abilities (high-spatial participants) are more accurate in memorizing map-based routes than participants with lower spatial abilities (low-spatial participants). On the other hand, added visual realism limits high-spatial participants in their route recall speed, while it seems not to influence the recall speed of low-spatial participants. Competition affects participants’ overall confidence positively, but does not affect their route recall performance neither in terms of accuracy nor speed. With this study, we provide further empirical evidence demonstrating that it is important to choose the appropriate map type considering task characteristics and spatial abilities. While satellite maps might be perceived as more fun to use, or visually more attractive than road maps, they also require more cognitive resources for many map-based tasks, which is true even for high-spatial users. 相似文献
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Fabrikant A.L. Spiesberger J.L. Silivra A.A. Hurlburt E.E. 《Oceanic Engineering, IEEE Journal of》1998,23(1):20-25
An acoustic tomography simulation is carried out in the eastern North Pacific ocean to assess whether climate trends are better detected and mapped with mobile or fixed receivers. In both cases, acoustic signals from two stationary sources are transmitted to ten receivers. Natural variability of the sound-speed field is simulated with the Naval Research Laboratory (NRL) layered-ocean model. A sequential Kalman-Bucy filter is used to estimate the sound speed field, where the a priori error covariance matrix of the parameters is estimated from the NRL model. A spatially homogeneous climate trend is added to the NRL fluctuations of sound speed, but the trend is not parameterized in the Kalman filter. Acoustic travel times are computed between the sources and receivers by combining sound speeds from the NRL model with those from the unparameterized climate trend. The effects of the unparameterized climate trend are projected onto parameters which eventually drift beyond acceptable limits. At that time, the unparameterized trend is detected. Mobile and fixed receivers detect the trend at about the same time. At detection time, however, maps from fixed receivers are less accurate because some of the unparameterized climate trend is projected onto tile spatially varying harmonics of the sound-speed field. With mobile receivers, the synthetic apertures suppress the projection onto these harmonics. Instead, the unparametrized trend is correctly projected onto the spatially homogeneous portion of the parameterized sound-speed field 相似文献
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Silivra A.A. Spiesberger J.L. Fabrikant A.L. Hurlburt H.E. 《Oceanic Engineering, IEEE Journal of》1997,22(1):143-150
A basin-scale acoustic tomography simulation is carried out for the northeast Pacific Ocean to determine the accuracy with which time must be kept at the sources when clocks at the receivers are accurate. A sequential Kalman filter is used to estimate sound-speed fluctuations and clock errors. Sound-speed fluctuations in the simulated ocean are estimated from an eddy-resolving hydrodynamic model of the Pacific forced by realistic wind fields at daily resolution from 1981-1993. The model output resembles features associated with El Nino and the Southern Oscillation, as well as many other features of the ocean's circulation. Using a Rossby-wave resolving acoustic array of four fixed sources and twenty drifting receivers, the authors find that the percentage of the modeled ocean's sound-speed variance accounted for with tomography is 92% at 400-km resolution, regardless of the accuracy of the clocks. Clocks which drift up to hundreds of seconds of error or more for a year do not degrade tomographic images of the model ocean. Tomographic reconstructions of the sound-speed field are insensitive to clock error primarily because of the wide variety of distances between the receivers from each source. Every receiver “sees” the same clock error from each source, regardless of section length, but the sound-speed fluctuations in the modeled ocean cannot yield travel times which lead to systematic changes in travel time that are independent of section length. The Kalman filter is thus able to map the sound-speed field accurately in the presence of large errors at the source's clocks 相似文献
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Kondratyeva L. N. Reva I. V. Aimanova A. K. Shomshekova S. A. Krugov M. A. 《Astrophysics》2021,64(3):306-315
Astrophysics - Several powerful outbursts have been observed during many years of observations of the symbiotic object MWC 560. The last active stage began in the autumn of 2018 and continues to... 相似文献
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We consider kinematic inhomogeneities (stellar groups) in the corona of the Ursa Major flow. We show that the orientation of the major axis of the error ellipse for each star is defined by its position relative to its own apex. We apply the AD-diagram method suggested by us earlier; a statistical analysis confirms the existence of stellar groups in the corona of the Ursa Major flow. 相似文献
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Reva Fabrikant 《Marine pollution bulletin》1984,15(7):249-253
Changes in the population density and size of the clam Parvilucina tenuisculpta were related to municipal waste effluent (in particular, organic nitrogen concentration) off the coast of Palos Verdes, California. Average clam size increased as sediment organic nitrogen concentration increased, but population density increased until organic nitrogen concentration reached a critical level when population density decreased dramatically. These effects were explained in terms of increased available nutrition (in the form of sediment organic nitrogen pollutants) enhancing both population and individual size growth. However, when a critical concentration of organic decomposition products was reached, population density decreased due to the toxicity of the released compounds. It is suggested that Parvilucina tenuisculpta would make a good bioindicator of organic enrichment pollution. 相似文献
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May Yuan Sara Fabrikant 《International journal of geographical information science》2014,28(6):1205-1208
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Data from the Hipparcos catalog are used to study the internal kinematics of the Hyades cluster. Cluster members whose proper motions and parallaxes are known with precisions not less than 5 mas/yr and 3 mas were used. The proper motions were reduced to the cluster center. A correlation between a component of the tangential velocity and the parallax provides evidence for possible rotation of the cluster. The total velocity gradient is 0.04±0.03 km s?1 pc?1. The rotation axis is located perpendicular to the direction to the Hyades apex on the celestial sphere. 相似文献