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41.
The popularity of video games has transcended entertainment crossing into the world of education. While the literature base on educational gaming is growing, there is still a lack of systematic study of this emerging technology’s efficacy. This quasi-experimental study evaluated a teacher created video game on genetics in terms of its affective and cognitive impact on student users. While statistical results indicated no differences (p > .05) in student learning as measured by our instrument, there were significant differences (p < .05) found in the participants’ level of engagement while interfacing with the video game. Implications on this emerging line of inquiry are discussed. 相似文献
42.
Responding to Kenneth Nichols' article in Computer (“The Age of Software Patents”, April 1999, pp. 25-31), the author disputes the two claims: “software patents are neither inherently good nor bad” and “software patents are here to stay.” The author thinks software patents are not impersonal technology, but rather a part of an intellectual patent system that is a social artifact. Because all social artifacts are fair game for judgments, software patents fall into that category. Not only does the author think it reasonable that an interested party examine the ethics and morality of any branch of the legal system (of which software patents and copyrights are a part), but he feels professionals in relevant areas have a social duty to do so. After exploring several arguments for software patents and copyrights, the author settles on the evitability of software patents, though he points out this does not ensure they will be avoided. However, he thinks there are good arguments for avoiding software patents for other more practical and just forms of monopoly for software 相似文献
43.
Matt Jones Steve Jones Gareth Bradley Nigel Warren David Bainbridge Geoff Holmes 《Personal and Ubiquitous Computing》2008,12(7):513-525
Listening to music on personal, digital devices whilst mobile is an enjoyable, everyday activity. We explore a scheme for
exploiting this practice to immerse listeners in navigation cues. Our prototype, ONTRACK, continuously adapts audio, modifying
the spatial balance and volume to lead listeners to their target destination. First we report on an initial lab-based evaluation
that demonstrated the approach’s efficacy: users were able to complete tasks within a reasonable time and their subjective
feedback was positive. Encouraged by these results we constructed a handheld prototype. Here, we discuss this implementation
and the results of field-trials. These indicate that even with a low-fidelity realisation of the concept, users can quite
effectively navigate complicated routes.
相似文献
Matt Jones (Corresponding author)Email: |
Steve JonesEmail: |
Gareth BradleyEmail: |
Nigel WarrenEmail: |
David BainbridgeEmail: |
Geoff HolmesEmail: |
44.
Comments on an article by C. M. Stoup and L. T. Benjamin, Jr. (see record 1983-24200-001), in which they used various editions of Graduate Study in Psychology, published by the American Psychological Association (APA), to report the GPAs and Graduate Record Examination scores of master's and doctoral students across various areas of psychology. It is cautioned that the use of Graduate Study in Psychology as a data source calls for skepticism, as there is sufficient reason to question some of the data that are submitted to the APA by psychology departments. (3 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
The duck interrenal cell possesses ultrastructural characteristics common to other steroid-secreting cells. Lipid droplets and mitochondria are abundant and lie principally at the apical end of the cell. Lipid droplets are not membrane-limited. Cisternae of smooth endoplasmic reticulum that are occasionally continuous with the less abundant rough endoplasmic reticulum are a prominent feature of the interrenal cell. Tubular profiles of rough endoplasmic reticulum often lie tangentially to mitochondria and ribosomes are either free, grouped in polyribosomal clusters, or bound to the endoplasmic reticulum. Mitochondria possess tubular cristae in the inner regions of the gland and frequently contain a paracrystalline array of small 10nm (o.d.) tubules and less frequently a hexagonal array of 40 nm trilaminar rings. Other cytoplasmic components include dense bodies, residual bodies, microtubules, microfilaments and specialized single membrane-bound vesicles. Gap junctions, intermediate junctions and interdigitating processes constitute the main intercellular associations. No tight junctions were identified. The single membrane-bound vesicles which are occasionally filled with a low electron-dense, lipid-like material form septate-like "junctions" with the plasma membrane. The septa bridge an intracellular gap of 15-17 nm. The vesicles are usually located near the subendothelial space at the basal and basilateral regions of the cell. Occasionally, vesicles fuse with the plasma membrane. It is suggested that these vesicles represent morphological evidence for the exocytotic release of steroid hormones. 相似文献
46.
During 6 months of post-natal development in the laboratory, the weight of the adrenal gland relative to body weight decreases exponentially. In the 3 day-old duckling a single intravenous dose of labelled corticosterone becomes distributed in a very large apparent volume and an "extracellular" pool that is greater than the extracellular fluid volume and the pattern of disappearance of labelled hormone from plasma is biphasic. Later during development the volumes of distribution decrease and the biphasic pattern of disappearance becomes less distinct until at 6 months only one phase of disappearance can be detected with confidence. No significant change in plasma corticosterone concentration occurs during this period of development in the laboratory. Estimations of the corticosterone secretory rates, however, indicate that whereas the adrenal weight-specific rate os secretion increases during the first 3 weeks and declines therafter, the bodyf weight-specific secretory rate continues to decline throughtout the period of increasing body weight. 相似文献
47.
48.
Diane M. Markoff Vince Cianciolo Chuck L. Britton Ronald G. Cooper Geoff L. Greene 《Journal of research of the National Institute of Standards and Technology》2005,110(4):449-452
We are developing a high-efficiency neutron detector with 1 cm position resolution and coarse energy resolution for use at high-flux neutron source facilities currently proposed or under construction. The detector concept integrates a segmented 3He ionization chamber with the position sensitive, charged particle collection methods of a MicroMegas detector. Neutron absorption on the helium produces protons and tritons that ionize the fill gas. The charge is amplified in the field region around a wire mesh and subsequently detected in current mode by wire strips mounted on a substrate. One module consisting of a high-voltage plate, a field-shaping high-voltage plate, a grid and wire strips defines a detection region. For 100 % efficiency, detector modules are consecutively placed along the beam axis. Analysis over several regions with alternating wire strip orientation provides a two-dimensional beam profile. By using 3He, a 1/v absorption gas, each axial region captures neutrons of a different energy range, providing an energy-sensitive detection scheme especially useful at continuous beam sources. 相似文献
49.
Data engineering is generally considered to be a central issue in the development of data mining applications. The success of many learning schemes, in their attempts to construct models of data, hinges on the reliable identification of a small set of highly predictive attributes. The inclusion of irrelevant, redundant, and noisy attributes in the model building process phase can result in poor predictive performance and increased computation. Attribute selection generally involves a combination of search and attribute utility estimation plus evaluation with respect to specific learning schemes. This leads to a large number of possible permutations and has led to a situation where very few benchmark studies have been conducted. This paper presents a benchmark comparison of several attribute selection methods for supervised classification. All the methods produce an attribute ranking, a useful devise for isolating the individual merit of an attribute. Attribute selection is achieved by cross-validating the attribute rankings with respect to a classification learner to find the best attributes. Results are reported for a selection of standard data sets and two diverse learning schemes C4.5 and naive Bayes. 相似文献
50.
That the technorealists little understand technology is unfortunate; that their mistaken ideas should be deemed uncontroversial is a revelation of the prevalent misunderstanding of technology that makes us tragically prone to be its slaves instead of its masters. These thoughts prompted the author to suggest that engineers have a professional responsibility to bring realism to technorealism. 相似文献