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51.
Mark Sherman Jonathan Rosenberg Ann Marks Jaap Akkerhuis 《Computer Standards & Interfaces》1991,11(3):177-182
Many advanced document systems provide a formatting mechanism called ‘style sheets’ Style sheets provide a great deal of flexibility in describing a document's format, and allow easy maintenance of different house styles for a collection of documents. In this paper, we describe the basics of general style sheet systems, argue that successful document interchange must include the exchange of style sheet information, and evaluate ODA's style mechanism against this requirement. 相似文献
52.
53.
54.
Mizumori Sheri J.; Rosenzweig Mark R.; Bennett Edward L. 《Canadian Metallurgical Quarterly》1985,99(2):220
The extent to which protein synthesis is involved in working memory was investigated with the protein synthesis inhibitor anisomycin (ANI). Male albino and Long-Evans rats were trained to perform accurately on a 12-arm radial maze when delays of 240 min were interposed between Choice 6 and Choice 7. Bilateral hippocampal cannulas were then implanted. Accuracy on Choices 7–22 was studied when ANI (80 μg/μl) or saline was injected either 30 min before Choice 1 or 5–20 min after Choice 6 in Exp I. Pretrial injection of ANI significantly impaired performance following the 240-min delay, whereas ANI injected during the delay had no such effect. In Exps II and III, the ANI-induced amnesia was replicated, and the temporal course of development of the amnesia was determined. Pretrial administration of ANI did not significantly affect retention after a 2-min delay but produced amnesia after delays of 15 min or longer. Data suggest that protein synthesis is important for the formation of temporary memories, provided the retention interval is long enough. It is suggested that working memory includes both short- and long-term components. Protein synthesis appears to be important for formation of the long-term component, but not the short-term component, of working memory. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
During large scale wildfires, suppression activities are carried out under the direction of an Incident Management Team (IMT). The aim of the research was to increase understanding of decision processes potentially related to IMT effectiveness. An IMT comprises four major functions: Command, Operations, Planning, and Logistics. Four methodologies were used to study IMT processes: computer simulation experiments; analyses of wildfire reports; interviews with IMT members; and cognitive ethnographic studies of IMTs. Three processes were important determinants of IMT effectiveness: information management and cognitive overload; matching component function goals to overall goals; and team metacognition to detect and counter task‐disruptive developments. These processes appear to be complex multi‐person analogues of individual Incident Command processes identified previously. The findings have implications for issues such as: creating IMTs; training IMTs; managing IMTs; and providing decision support to IMTs. 相似文献
56.
Jonathan P. Belnoue Giang D. Nguyen Alexander M. Korsunsky 《International Journal of Fracture》2007,144(1):53-60
This paper presents a new 1-D non-local damage-plasticity deformation model for ductile materials. It uses the thermodynamic
framework described in Houlsby and Puzrin (2000) and holds, nevertheless, some similarities with Lemaitre’s (1971) approach.
A 1D finite element (FE) model of a bar fixed at one end and loaded in tension at the other end is introduced. This simple
model demonstrates how the approach can be implemented within the finite element framework, and that it is capable of capturing
both the pre-peak hardening and post-peak softening (generally responsible for models instability) due to damage-induced stiffness
and strength reduction characteristic of ductile materials. It is also shown that the approach has further advantages of achieving
some degree of mesh independence, and of being able to capture deformation size effects. Finally, it is illustrated how the
model permits the calculation of essential work of rupture (EWR), i.e. the specific energy per unit cross-sectional area that
is needed to cause tensile failure of a specimen. 相似文献
57.
Alexander Chroneos Nicholas J. Ashley Kaajal H. Desai John F. Maguire R. W. Grimes 《Journal of Materials Science》2007,42(6):2024-2029
The structures of a number of hydroxide and oxyhydroxide minerals have previously been reported without the hydrogen positions
explicitly defined. Here we use two atomic scale computer simulation techniques, one based on classical ionic potentials,
the other on density functional theory (DFT), to predict these positions. The aim is not only to provide data that can be
used as the basis for future experimental structure optimizations but also model parameters that can be used to predict complex
hydroxide structures. The efficacy of the approach is demonstrated through the comparison of predicted and experimental data
for minerals whose hydrogen positions are known. 相似文献
58.
Alexander Katsman Shalom Cohen Menachem Bamberger 《Journal of Materials Science》2007,42(16):6996-7003
This work deals with the development of Mg-based alloys with enhanced properties at elevated temperatures. This is achieved
by precipitation of binary phases such as MgZn2 and Mg2Sn during the aging of these alloys. The aim of the present work is to develop and calibrate a model for precipitation hardening
in Mg-based alloys, as different types of precipitates form simultaneously. The modified Langer-Schwartz approach, while taking
into account nucleation, growth and coarsening of the new phase precipitations, was used for the analysis of precipitates’
evolution and precipitation hardening during aging of Mg-based alloys. Two strengthening mechanisms associated with particle-dislocation
interaction (shearing and bypassing) were considered to be operating simultaneously due to particle size-distribution. Parameters
of the model, R
N
i and k
σ i
, were found by fitting of calculated densities and average sizes of precipitates with ones estimated from experiments. The
effective diffusion coefficients of phase formation processes, which determine the strengthening kinetics, were estimated
from the hardness maximum positions on the aging curves. 相似文献
59.
Alexander E. Meyerovich 《Journal of Low Temperature Physics》2004,134(1-2):163-168
Similarities between alkali gases in optical lattices with non-integer occupation of the lattice sites and quantum crystals are explored. The analogy with the vacancy liquid provides an agternative explanation to the Mott transition for the recent experiment on the phase transition in the lattice. The vacancy liquid can undergo BEC with T c within experimental reach. Direct and vacancy-assisted mechanisms of the band motion for hyperfine impurities are discussed. The presence of vacancies can resugt in the spatial decomposition of the system into pure hyperfine components. Below BEC for the vacancies, the impurity component resembles 3He in 3He-Hell mixtures. 相似文献
60.
Jianxin Wei Mark R Pickering Michael R Frater John F Arnold John A Boman Wenjun Zeng 《IEEE transactions on image processing》2005,14(8):1033-1042
It is well known that tile-boundary artifacts occur in wavelet-based lossy image coding. However, until now, their cause has not been understood well. In this paper, we show that boundary artifacts are an inescapable consequence of the usual methods used to choose tile size and the type of symmetric extension employed in a wavelet-based image decomposition system. This paper presents a novel method for reducing these tile-boundary artifacts. The method employs odd tile sizes (2N + 1 samples) rather than the conventional even tile sizes (2N samples). It is shown that, for the same bit rate, an image compressed using an odd tile length low-pass first (OTLPF) convention has significantly less boundary artifacts than an image compressed using even tile sizes. The OTLPF convention can also be incorporated into the JPEG 2000 image compression algorithm using extensions defined in Part 2 of this standard. 相似文献