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31.
Hay Julia L.; Milders Maarten M.; Sahraie Arash; Niedeggen Michael 《Canadian Metallurgical Quarterly》2006,32(4):885
Recent visual marking studies have shown that the carry-over of distractor inhibition can impair the ability of singletons to capture attention if the singleton and distractors share features. The current study extends this finding to first-order motion targets and distractors, clearly separated in time by a visual cue (the letter X). Target motion discrimination was significantly impaired, a result attributed to the carry-over of distractor inhibition. Increasing the difficulty of cue detection increased the motion target impairment, as distractor inhibition is thought to increase under demanding (high load) conditions in order to maximize selection efficiency. The apparent conflict with studies reporting reduced distractor inhibition under high load conditions was resolved by distinguishing between the effects of "cognitive" and "perceptual" load. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
32.
This work examines two methods for evolving dimensionally correct equations on the basis of data. It is demonstrated that the use of units of measurement aids in evolving equations that are amenable to interpretation by domain specialists. One method uses a strong typing approach that implements a declarative bias towards correct equations, the other method uses a coercion mechanism in order to implement a preferential bias towards the same objective. Four experiments using real-world, unsolved scientific problems were performed in order to examine the differences between the approaches and to judge the worth of the induction methods.Not only does the coercion approach perform significantly better on two out of the four problems when compared to the strongly typed approach, but it also regularizes the expressions it induces, resulting in a more reliable search process.A trade-off between type correctness and ability to solve the problem is identified. Due to the preferential bias implemented in the coercion approach, this trade-off does not lead to sub-optimal performance. No evidence is found that the reduction of the search space achieved through declarative bias helps in finding better solutions faster. In fact, for the class of scientific discovery problems the opposite seems to be the case. 相似文献
33.
Giuseppina Puzzilli Bogdan Govoreanu Fernanda Irrera Maarten Rosmeulen Jan Van Houdt 《Microelectronics Reliability》2007,47(4-5):508
In this work, charge trapping in SiO2/Al2O3 dielectric stacks is characterized by means of pulsed capacitance–voltage measurements. The proposed technique strongly reduces the measurement time and, as a consequence, the impact of charge trapping on the measurement results. Flat band voltage shift and fast current transient during short stress pulses are systematically monitored and the centroid and the amount of the trapped charge are extracted using a first-order model. 相似文献
34.
The paper describes the findings from a study of students’ use and experience of technologies. A series of in-depth case studies were carried out across four subject disciplines, with data collected via survey, audio logs and interviews. The findings suggest that students are immersed in a rich, technology-enhanced learning environment and that they select and appropriate technologies to their own personal learning needs. The findings have profound implications for the way in which educational institutions design and support learning activities. 相似文献
35.
Maarten Franssen 《Research in Engineering Design》2005,16(1-2):42-56
Arrow’s theorem poses limits to the translation of the different preference orders on a set of options into a single preference order. In this paper, I argue, against opinions to the contrary, that Arrow’s theorem applies fully to multi-criteria decision problems as they occur in engineering design, making solution methods to such problems subject to the theorem’s negative result. Discussing the meaning and consequences for engineering design, I review the solution methods to such problems presented in the engineering design literature in the light of the theorem. It appears that underlying such methods is a mix-up of two fundamentally different problem definitions, as the theory of multi-attribute preferences, which is often presented as an adequate approach for engineering design, in fact fails to address the Arrowian multi-criteria problem. Finally, I suggest ways how engineering design might adopt results from discussions of Arrow’s theorem elsewhere in resolving its multi-criteria decision problems. 相似文献
36.
Guido Notermans Anco Heringa Maarten van Dort Sander Jansen Fred Kuper 《Microelectronics Reliability》2000,40(1):117
In this paper a new model for localized breakdown in NMOSTs under ESD stress is developed, which accounts for the reduced ESD strength in silicided devices. The model explains the impact of a stabilizing drain resistance on second breakdown current for both silicided and unsilicided protections. 相似文献
37.
Maarten Overdijk Wouter van Diggelen 《International Journal of Computer-Supported Collaborative Learning》2008,3(2):165-192
The use and effects of a CSCL-tool are not always predictable from the properties of the tool alone, but depend on how that
tool is appropriated. This paper presents the findings from a case study about the appropriation of a graphical shared workspace.
When students are presented with a new tool they may encounter competing constraints and multiple possibilities for interacting
with it. We argue that during critical events the students make choices, and in order to collaborate, coordinate these choices
as a group. We study appropriation by looking into the ways in which small groups organize their contributions during a computer-mediated
argumentative discussion. The results of our study illustrate how certain principles for organization emerge from an implicit
negotiation of conventions, with mutual influence between the students and the tool. 相似文献
38.
39.
Maarten Hoeijmakers Viktor Kornilov Ines Lopez Arteaga Philip de Goey Henk Nijmeijer 《Combustion and Flame》2014
This paper shows that a flame can be an intrinsically unstable acoustic element. The finding is clarified in the framework of an acoustic network model, where the flame is described by an acoustic scattering matrix. The instability of the flame acoustic coupling is shown to become dominating in the limit of no acoustic reflections. This is in contrast to classical standing-wave thermoacoustic modes, which originate from the positive feedback loop between system acoustics and the flame. These findings imply that the effectiveness of passive thermoacoustic damping devices is limited by the intrinsic stability properties of the flame. 相似文献
40.