5,543 research outputs found
Temporal dynamics of travelling theta wave activity in infants responding to visual looming
A fundamental property of most animals is the ability to see whether an object is approaching on a direct collision course and, if so, when it will collide. Using high-density electroencephalography in 5- to 11-month-old infants and a looming stimulus approaching under three different accelerations, we investigated how the young human nervous system extracts and processes information for impending collision. Here we show that infants' looming related brain activity is characterized by theta oscillations. Source analyses reveal clear localised activity in the visual cortex. Analysing the temporal dynamics of the source waveform, we provide evidence that the temporal structure of different looming stimuli is sustained during processing in the more mature infant brain, providing infants with increasingly veridical time-to-collision information about looming danger as they grow older and become mobile
Special studies of AROD system concepts and designs
Signal processing techniques for range and range rate measurements in airborne range and orbit determinatio
L'Histoire religieuse en France et en Espagne, Colloque international (Casa de Velázquez, 2-5 avril 2001). [Reseña]
Reseña de: Benoît PELLISTRANDI (éd.), L'Histoire religieuse
en France et en Espagne, Colloque international
(Casa de Velázquez, 2-5 avril
2001), Casa de Velázquez, Madrid, 2004, 506
pp
PolĂtica, cultura y sociedad en la España de Franco (1939-1975), tomo II/2, Los intentos de las minorĂas dirigentes de modernizar el Estado tradicional español (1947-1956). [Reseña]
Reseña de: Gonzalo Redondo, PolĂtica, cultura y sociedad en la España de Franco
(1939-1975), tomo II/2, Los intentos de las minorĂas dirigentes de modernizar
el Estado tradicional español (1947-1956), eunsa, Pamplona 2009, 1.120 pp
Spontaneous Ratchet Effect in a Granular Gas
The spontaneous clustering of a vibrofluidized granular gas is employed to
generate directed transport in two different compartmentalized systems: a
"granular fountain" in which the transport takes the form of convection rolls,
and a "granular ratchet" with a spontaneous particle current perpendicular to
the direction of energy input. In both instances, transport is not due to any
system-intrinsic anisotropy, but arises as a spontaneous collective symmetry
breaking effect of many interacting granular particles. The experimental and
numerical results are quantitatively accounted for within a flux model.Comment: 4 pages, 5 figures; Fig. 4 has been reduced in size and qualit
Telepresence robotics in an academic library: A study of exposure and adaptation among patrons and employees
Purpose
Librarians are working with telepresence robotics for various uses, particularly as a communication method inhabiting a space between video chat and face-to-face interactions. The library at Western Michigan University partnered with the Western Michigan University Communication and Social Robotics Lab to showcase this emerging technology in a high-traffic setting utilized by students of every level and major. The purpose of this paper is to discuss patron reactions to this technology exhibition in the library, beta testing of a telepresence robot in various public services tasks, and library employee attitudes toward this unfamiliar technology before and after one-on-one training. Design/methodology/approach
The project gathered data through three studies. In study 1, feedback forms were filled out by patrons who interacted with or piloted the robot. In study 2, observations by the librarians piloting the robot for various public services activities were recorded in a log. In study 3, employees were invited to complete a pretest designed to solicit perceptions and attitudes regarding the use of the robot, become trained in navigating the robot, and complete a posttest for comparison purposes. Results were analyzed to find trends and highlight perceived uses for the technology. Findings
Patrons and library employees gave positive feedback regarding the novelty of the technology and appreciated its remote communication capability. Trialed uses of the technology for public services yielded positive results when the TR was used for public relations, such as at special events or in greeting tours, and yielded less positive results when used for reference purposes. Library employees comfort with and perceived utility of the robot grew consistently across departments, levels of experience and employment types after a personal training session. Originality/value
Although libraries in recent years have surveyed users regarding TR technology, this paper captures quantitative and qualitative data from a library employee training study regarding perception of the technology. Exploration of the public services uses and library employee acceptance of TR technology is valuable to those contemplating expending time and resources in similar endeavors
An Alternate Method for Fourier Transform Infrared (FTIR) Spectroscopic Determination of Soil Nitrate Using Derivative Analysis and Sample Treatments
This study aimed at examining effective sample treatments and spectral processing for an alternate method of soil nitrate determination using the attenuated total reflectance (ATR) of Fourier transform infrared (FTIR) spectroscopy. Prior to FTIR measurements, soil samples were prepared as paste to enhance adhesion between the ATR crystal and sample. The similar nitrate peak heights of soil pastes and their supernatants indicated that the nitrate in the liquid portion of the soil paste mainly responded to the FTIR signal. Using a 0.01-M CaSO4 solution for the soil paste, which has no interference bands in the characteristic spectra of the analyte, increased the concentration of the nitrates to be measured. Second-order derivatives were used in the prediction model to minimize the interference effects and enhance the performance. The second-order derivative spectra contained a unique nitrate peak in a range of 1,400-1,200 cm(-1) without interference of carbonate. A partial least square regression model using second-order derivative spectra performed well (R (2) = 0.995, root mean square error (RMSE) = 23.5, ratio of prediction to deviation (RPD) = 13.8) on laboratory samples. Prediction results were also good for a test set of agricultural field soils with a CaCO3 concentration of 6% to 8% (R (2) = 0.97, RMSE = 18.6, RPD = 3.5). Application of the prediction model based on soil paste samples to nitrate stock solution resulted in an increased RMSE (62.3); however, validation measures were still satisfactory (R (2) = 0.99, RPD = 3.0
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