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11.
Sixth graders’ evaluation strategies when reading Internet search results: an eye-tracking study 总被引:1,自引:0,他引:1
Jarkko Hautala Carita Kiili Yvonne Kammerer Otto Loberg Sanna Hokkanen Paavo H. T. Leppänen 《Behaviour & Information Technology》2018,37(8):761-773
Eye-tracking technology was used to examine Internet search result evaluation strategies adopted by sixth-grade students (N?=?36) during ten experimental information search tasks. The relevancy of the search result’s title, URL, and snippet components was manipulated and selection of search results as well as looking into probabilities on the search result components was analysed. The results revealed that during first-pass inspection, students read the search engine page by first looking at the title of a search result. If the title was relevant, the probability of looking at the snippet of the search result increased. During second-pass inspection, there was a high probability of students focusing on the most promising search result by inspecting all of its components before making their selection. A cluster analysis revealed three viewing strategies: half of the students looked mainly at the titles and snippets; one-third with high probability examined all components; and one-sixth mainly focused on titles, leading to more frequent errors in search result selection. The results indicate that students generally made a flexible use of both eliminative and confirmatory evaluation strategies when reading Internet search results, while some seemed to not pay attention to snippet and URL components of the search results. 相似文献
12.
Conservation laws in cellular automata (CA) are studied as an abstraction of the conservation laws observed in nature. In
addition to the usual real-valued conservation laws we also consider more general group-valued and semigroup-valued conservation
laws. The (algebraic) conservation laws in a CA form a hierarchy, based on the range of the interactions they take into account.
The conservation laws with smaller interaction ranges are the homomorphic images of those with larger interaction ranges,
and for each specific range there is a most general law that incorporates all those with that range. For one-dimensional CA,
such a most general conservation law has—even in the semigroup-valued case—an effectively constructible finite presentation,
while for higher-dimensional CA such effective construction exists only in the group-valued case. It is even undecidable whether
a given two-dimensional CA conserves a given semigroup-valued energy assignment. Although the local properties of this hierarchy
are tractable in the one-dimensional case, its global properties turn out to be undecidable. In particular, we prove that
it is undecidable whether this hierarchy is trivial or unbounded. We point out some interconnections between the structure
of this hierarchy and the dynamical properties of the CA. In particular, we show that positively expansive CA do not have
non-trivial real-valued conservation laws. 相似文献
13.
Ville Rimpiläinen Sami Poutiainen Lasse M. Heikkinen Tuomo Savolainen Marko Vauhkonen Jarkko Ketolainen 《Chemical engineering science》2011,(18):4090
Electrical capacitance tomography (ECT) was utilized for monitoring of high-shear mixing and high-shear granulation processes. A finite element method (FEM)-based reconstruction algorithm was utilized to take into account the specific geometrical characteristics of the experimental set-up. Two-dimensional ECT tomograms, mixing index curves and permittivity fractions were computed based on the measurements, and their suitability in the analysis of the processes was assessed. It was found that the different mixing processes and the different granulation processes could be analyzed based on these quantities. 相似文献
14.
Jarkko Puustinen Jyrki Lappalainen Jussi Hiltunen Vilho Lantto 《Journal of the European Ceramic Society》2010,30(2):429-434
Optical characterization methods, like spectrophotometry at UV–vis-NIR wavelengths and prism-coupler method, were applied to polycrystalline Pb(ZrxTi1?x)O3 thin films at various thicknesses. Thin films were deposited at room temperature by pulsed laser deposition on MgO (1 0 0) substrates and post-annealed at different temperatures. X-ray diffraction and atomic force microscopy were used to characterize the crystal structure and surface morphology of the thin films, respectively.Well oscillating transmission with a sharp fall near the absorption edge was found in films with high orientation and low surface roughness. Changes in the surface morphology and crystal orientation were found to modulate optical interference maxima and minima of the transmittance spectra and to increase the width of the TE0 mode (Δβ ≈ 0.06) indicating an increase in the scattering losses of the films. Single-phase oriented films had sharpest coupling values (Δβ ≈ 0.005) of the TE0 mode. 相似文献
15.
Mikko Hautala Harry J. Whitlow 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1985,6(3):466-473
The anisotropy in the spatial distributions of recoil-flux and recoil-momentum have been studied by Monte Carlo simulation for the specific case of amorphous germanium bombarded with Ar+ ions. For all the energies investigated, (1.25 to 320 keV) both the recoil-flux and momentum-flux distributions are strongly backwards directed at the surface, becoming forwards directed at greater depths. Further the angular distributions are (relatively) insensitive to the choice of interatomic potential. The calculations show that the backwards-directedness of sputtered particle angular distributions may be completely explained by the anisotropy in the recoil flux. It is also demonstrated that the adoption of more realistic surface models, than the usual infinite target approximation does not lead to significant changes in the angular distribution of recoil-, momentum- and sputtered particle-fluxes. 相似文献
16.
I. Koponen M. Hautala 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》1994,90(1-4):396-400
Thermalization of ion bombardment induced large and sparse cascades in metals is studied. We introduce a model where nonequilibrium electron and ion distributions relax simultaneously, and coupling between the thermal ions and valence electrons allows heat exchange between electronic and ionic systems. This model takes into account the competing time scales of the relaxation processes and the heat outdiffusion from the cascade zone. Nearly free conduction electron bands are assumed, which restricts the applicability of the model to simple metals only. It is shown that in cascades with an extent of about 10 nm or more, a considerable part of the energy, residing initially in the electronic system, may reappear in the ionic system in the cascade zone. Ions in cascades with radius larger than 20 nm take up nearly all of the energy available in the cascade zone. Due to this energy transfer, the ionic system may experience appreciable additional heating in large cascades. 相似文献
17.
Phillips D. Allen; Carlisle Cynthia S.; Hautala Robert; Larson Richard 《Canadian Metallurgical Quarterly》1985,77(4):408
Analyzed the relationship of teacher personality as measured by the 16PF to teacher behaviors in physical education as measured by a physical education teacher assessment instrument. Teacher behavior data were obtained from 18 physical education teachers in 3 junior high schools, 5 middle schools, and 6 elementary schools who volunteered to teach a 10-lesson beginning volleyball unit using their own individual teaching styles. Eight students were randomly selected from each teacher's class (n?=?144). Results indicate the primary personality traits of assertiveness, expediency, questioning, imaginativeness, genuineness, confidence, and experimenting related significantly to many important teacher and student behaviors observed in a typical physical education class. Teachers who scored high on these personality traits tended to exhibit a higher level of knowledge, utilized objectives and testing more effectively, and were more flexible and appropriate in their instruction. They also provided more planned instruction and more positive feedback. Teachers who scored high in assertiveness, questioning, and imaginativeness tended to provide their students with more time on task and a higher quality of practice time. Students of teachers who scored high in independence, assertiveness, questioning, and imaginativeness learned more than did students of teachers who were low in these personality traits. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
18.
On Design of Parallel Memory Access Schemes for Video Coding 总被引:3,自引:0,他引:3
Jarno K. Tanskanen Reiner Creutzburg Jarkko T. Niittylahti 《The Journal of VLSI Signal Processing》2005,40(2):215-237
Some of the modern powerful digital signal processors (DSPs) have byte-addressable internal data memory. This property is valuable especially in computationally demanding inter frame video encoding, where data accesses are typically unaligned according to word boundaries. The byte-addressable memory allows load or store command to start accessing from any byte-address, providing at most as many successive bytes from subsequent addresses as data bus can handle in parallel. Maybe the simplest way to construct such a byte-addressable memory is to use N 8-bit memory modules or banks to be accessed in parallel, when N is data bus width in bytes. However, in addition to byte-addressable subsequent bytes, memory consisting of parallel memory modules can provide much more versatile addressing capabilities with reasonable implementation cost. Versatile access formats can significantly reduce the need for data reordering in the register file. At first, we provide motivation for using parallel memory architecture with versatile access formats as an internal on-chip data memory of modern DSP. After this, notations are described and general view of parallel memory design is given. We propose some example parallel data memory architecture designs with data access formats especially helpful in H.263 encoding and MPEG-4 core profile motion and texture encoding. The examples are given for different data bus widths (16, 32, 64, and 128 bits). Finally, performance is shortly compared to other memory architectures and area, delay, and power figures are estimated.Jarno K. Tanskanen was born in Joensuu, Finland in 1975. He studied analog and digital electronics in the Department of Electrical Engineering, and computer architecture in the Department of Information Technology at Tampere University of Technology, where he received his M.Sc. degree in 1999. He is currently working as a research scientist in the Institute of Digital and Computer Systems at TUT. His Dr.Tech. research concerns parallel processing of video compression. jarno.tanskanen@tut.fiReiner Creutzburg received his Diploma in Mathematics in 1976 and attained his Ph.D. in Mathematics in 1984 from the Rostock University, Germany. Prof. Creutzburg has published 3 books, filed 2 patents, and produced approximately 100 articles, preprint, and conference papers. Professional Experience: Since 2000—Part-time Professor for Multimedia technology, Tampere University of Technology, Finland. Since 1992—Full-time Professor of Computer Science, Fachhochschule Brandenburg-University of Applied Sciences, Brandenburg, Germany. 1990 to 1992—Assistant Professor, University of Karlsruhe, Institute of Algorithms and Cognitive Systems, Germany. 1987 to 1989—Head of the Research Section Image Processing. 1986 to 1989—Founder and Head of the International Base Laboratory of Image Processing and Computer Graphics for East European countries at the Central Institute of Cybernetics and Information Processes of the Academy of Sciences (Berlin), Germany. 1976 to 1989—Researcher and Assistant Professor in various Universities and the Academy of Sciences, Central Institute of Cybernetics and Information, Berlin. creutzburg@fh-brandenburg.deJarkko T. Niittylahti was born in Orivesi, Finland, in 1962. He received the M.Sc, Lic.Tech, and Dr.Tech degrees at Tampere University of Technology (TUT) in 1988, 1992, and 1995, respectively. From 1987 to 1992, he was a researcher at TUT. In 1992–93, he was a researcher at CERN in Geneva, Switzerland. In 1993–95, he was with Nokia Consumer Electronics, Bochum, Germany, and in 1995–97 with Nokia Research Center, Tampere, Finland. In 1997–2000, he was a Professor at Signal Processing Laboratory, TUT, and in 2000–2002 at Institute of Digital and Computer Systems, TUT. Currently, he is a Docent of Digital Techniques at TUT and the managing director of Staselog Ltd. He is also a co-founder and President of Atostek Ltd. He is interested in designing digital systems and architectures. jarkko.niittylahti@tut.fi 相似文献
19.
Two patients with chlamydial pneumonia of infancy are described. One recovered spontaneously without any specific antichlamydial treatment. The other, prior to a belated antimicrobial therapy, developed a persistent and protracted respiratory illness characterized by wheezing. Our observations suggest that: (1) untreated chlamydial pneumonia of infancy may spontaneously resolve, or may become a persistent and protracted disease, and (2) wheezing may be a very prominent manifestation of the disease and should be differentiated from wheezing due to bronchiolitis and bronchial asthma. 相似文献
20.
Ville Saari Jussi Mustola Jarkko Jussila Jussi Ryynänen Saska Lindfors Kari Halonen 《Analog Integrated Circuits and Signal Processing》2008,54(2):77-84
SiGe BiCMOS low-pass filter for a multicarrier WCDMA base-station receiver is described in this paper. The 4th-order Chebyshev
filter with a 0.1-dB passband ripple is designed to drive a high-resolution A/D converter. The −3-dB frequency of the implemented
filter can be programmed to four different bandwidths: 2.5, 5, 7.5, and 10 MHz depending on the number of received WCDMA channels.
The filter achieves +9.7-dBV in-band IIP3, +20-dBV out-of-band IIP3, and 8.5-nV/√Hz input-referred noise density with 10-MHz
bandwidth. The circuit uses a 2.5 V supply and has been fabricated in a 0.25-μm SiGe BiCMOS process. 相似文献