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41.
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
42.
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: |
43.
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
44.
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
45.
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
46.
47.
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
48.
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
49.
BA McCracken MB Judkins LJ Krysl DW Holcombe KK Park 《Canadian Metallurgical Quarterly》1993,71(7):1932-1939
Two experiments were conducted to study the effects of methionine supplementation on ruminal fermentation and digesta kinetics. In Exp. 1, nine ruminally cannulated beef heifers (average initial BW = 527 kg) in a crossover design were fed low-quality grass hay and cottonseed meal with or without 11.4 g of supplemental methionine (polysaccharide-coated). Particulate and fluid kinetics, rate of DM and NDF disappearance, ruminal VFA and NH3 N concentrations, and pH were not altered (P > .10) by supplemental methionine; however, ruminal purine concentration was greater (P < .05) in methionine-supplemented heifers than in unsupplemented heifers. In Exp. 2, 12 ruminally cannulated Holstein steers (average initial BW = 622 kg) grazing a fescue pasture were allotted to one of three groups: no supplemental methionine (CON) or 11.4 g of supplemental methionine fed at 0700 (AM) or at 1200 (PM). Forage intake, particulate kinetics, ruminal fluid kinetics, pH, VFA, and NH3 N concentrations were not altered (P > .10) by supplemental methionine or supplementation time. In situ rate of DM and NDF disappearance was greater (P < .05) in supplemented steers than in CON steers; AM steers exhibited faster (P < .05) rates than PM steers. Overall, methionine supplementation of low-quality forage increased ruminal purine concentration but did not alter in situ fermentation or digesta passage, whereas supplementation at 0700, but not at 1200, of steers grazing fescue forage increased rate of NDF fermentation. 相似文献
50.
In‐situ Observations of Nanoscale Effects in Germanium Nanowire Growth with Ternary Eutectic Alloys 下载免费PDF全文
Subhajit Biswas Colm O'Regan Michael A. Morris Justin D. Holmes 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(1):103-111
Vapour‐liquid‐solid (VLS) techniques are popular routes for the scalable synthesis of semiconductor nanowires. In this article, in‐situ electron microscopy is used to correlate the equilibrium content of ternary (Au0.75Ag0.25–Ge and Au0.65Ag0.35–Ge) metastable alloys with the kinetics, thermodynamics and diameter of Ge nanowires grown via a VLS mechanism. The shape and geometry of the heterogeneous interfaces between the liquid eutectic and solid Ge nanowires varies as a function of nanowire diameter and eutectic alloy composition. The behaviour of the faceted heterogeneous liquid–solid interface correlates with the growth kinetics of the nanowires, where the main growth facet at the solid nanowire–liquid catalyst drop contact line lengthens for faster nanowire growth kinetics. Pronounced diameter dependent growth kinetics, as inferred from liquid–solid interfacial behaviour, is apparent for the synthesised nanowires. Direct in‐situ microscopy observations facilitates the comparison between the nanowire growth behaviour from ternary (Au–Ag–Ge) and binary (Au–Ge) eutectic systems. 相似文献