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11.
Purver Matthew Sadrzadeh Mehrnoosh Kempson Ruth Wijnholds Gijs Hough Julian 《Journal of Logic, Language and Information》2021,30(2):379-406
Journal of Logic, Language and Information - Despite the incremental nature of Dynamic Syntax (DS), the semantic grounding of it remains that of predicate logic, itself grounded in set theory, so... 相似文献
12.
In this study, we examined the unfolding processes of nativeß2-microglobulin and two related variants, one withan N-terminal hexapeptide deletion 相似文献
13.
Allemann C Gordillo R Clemente FR Cheong PH Houk KN 《Accounts of chemical research》2004,37(8):558-569
Computational studies have led to models to understand some classic and contemporary asymmetric reactions involving organocatalysts. The Hajos-Parrish-Eder-Sauer-Wiechert reaction and intermolecular aldol reactions as well as Mannich reactions and oxyaminations catalyzed by proline and other amino acids, and Diels-Alder reactions catalyzed by MacMillan's chiral amine organocatalysts have been studied with density functional theory. Quantitative predictions for several new catalysts and reactions are provided. 相似文献
14.
IT infrastructure is definitely going green. From significant new regulations for IT equipment disposal to stringent energy-efficiency specifications for PCs and monitors to national standards for data center power savings, Green IT is an "in" topic. But many problems are unsolved. Will telecommuting make a difference or is it too difficult to manage? Will cloud computing reduce the number of large data centers? Can legislation diminish e-waste challenges? 相似文献
15.
Jens Hauslage Medea Abbrecht Lars Hanke Ruth Hemmersbach Claudia Koch Wolfgang Hanke Florian P. M. Kohn 《Microgravity science and technology》2016,28(6):633-638
All life on earth has been established under conditions of stable gravity of 1g. Nevertheless, in numerous experiments the direct gravity dependence of biological processes has been shown on all levels of organization, from single molecules to humans. To study the effects especially of microgravity on biological systems, a variety of platforms are available, from drop towers to the ISS. Due to the costs of these platforms and their limited availability, as an alternative, numerous simulators have been developed for so called “simulated” microgravity. A classical systems is a clinostat, basically rotating a sample around one axis, and by integration of the gravity vector for 360° arguing that thus the effects of gravity are depleted. Indeed, a variety of studies has shown that taking out the direction of gravity from a biological system often results in consequences similar to the exposure of the system to real microgravity. Nevertheless, the opposite has been shown, too, and as a consequence the relevance of clinostats in microgravity research is still under discussion. To get some more insight into this problem we have constructed a small fluorescence clinostat and have studied the effects of clinorotation on the cytosolic calcium concentration of neuroglioma cells. The results have been compared to experiments with identical cells in real microgravity, utilizing parabolic flight missions. Our results show that in case of a cell suspension used in a small florescence clinostat within a tube diameter of 2mm, the effects of clinorotation are comparable to those under real microgravity, both showing a significant increase in intracellular calcium concentration. 相似文献
16.
17.
Manoli Pifarre Ruth Cobos 《International Journal of Computer-Supported Collaborative Learning》2010,5(2):237-253
This paper aims to better understand the development of students’ metacognitive learning processes when participating actively
in a CSCL system called KnowCat. To this end, a longitudinal case study was designed, in which 18 university students took
part in a 12-month (two semesters) learning project. The students followed an instructional process, using specific features
of the KnowCat design to support and improve their interaction processes, especially peer-learning processes. Our research
involved both supervising the students’ collaborative learning processes throughout the learning project and focusing our
analysis on the qualitative evolution of their interaction processes and of their metacognitive learning processes. The results
of the current research suggest that the pedagogical use of the KnowCat system may favour and improve the development of the
students’ metacognitive learning processes. In addition, the implications of the design of CSCL networks and related pedagogical
issues are discussed. 相似文献
18.
Centralized heavyweight collectors have been used to collect text-based web objects for building search engines. However,
these collectors do not meet the need of collecting big web objects such as images and videos. We propose a lightweight mobile
on-call object collector for the world wide web. Using this approach, we can deploy a collector easily on the site being indexed.
We present a prototype system consisting of mobile Java collectors and search engines for collecting HTML/image objects. We
provide analysis to find a lower bound in terms of total data transfer time required. This idealized scenario is complemented
with another model based on implementation of the HTTP over TCP. The lower bound and the upper bound of the gains accrued
are then validated using experiments.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
19.
Ruth F. Curtain 《Automatica》2012,48(1):139-144
Recently, the class of spatially invariant systems was introduced with motivating examples of partial differential equations on an infinite domain. For these it was shown that by taking Fourier transforms, one obtains infinitely many finite-dimensional systems with a scalar parameter. The idea is that, for the LQR controller design for these systems, one can solve the parameterized LQR-Riccati equation pointwise. While for simple first order systems like the heat equations this approach works, for second order systems like wave or beam equations it is easy to construct examples for which this approach fails. Here we give a correct formulation for second order partial differential systems including wave and beam type equations. 相似文献
20.
Jacob Theodore; Fagin Robert; Perry Joseph; Van Dyke Ruth A. 《Canadian Metallurgical Quarterly》1975,11(3):393
Upper-, middle-, and lower-class parents were asked to explain a proverb which had both "growth" and "stability" interpretations to their 11- and 16-yr-old sons. The growth interpretation was overwhelmingly endorsed by most parents. With 16-yr-olds, lower-middle-class parents continued to endorse the growth interpretation; most upper-class parents endorsed the stability interpretation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献