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排序方式: 共有262条查询结果,搜索用时 15 毫秒
1.
Rice Catherine; Koinis Daphne; Sullivan Kate; Tager-Flusberg Helen; Winner Ellen 《Canadian Metallurgical Quarterly》1997,33(1):54
68 3-yr-olds received a standard appearance–reality task along with either a trick task, in which the appearance question was placed in the context of a deceptive game, or a reduced information processing task, in which a dual object (e.g., a sponge-rock) was presented along with an object that matched the dual object's identity (a sponge) and one that matched the dual object's appearance (a rock). Children were more likely to pass either the trick or reduced information processing task and fail the standard than the reverse. Thus, 3-yr-olds can grasp the distinction between appearance and reality (a) when their goal is to trick someone, which may prime them to think about the other's mental state, and (b) when they do not need to hold conflicting object identities in mind at the same time. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
A GENTRIFICATION RESEARCH AGENDA FOR THE 1990s 总被引:1,自引:0,他引:1
Daphne Spain 《Journal of Urban Affairs》1992,14(2):125-134
ABSTRACT: This paper identifies a range of gentrification research topics meriting further attention in the 1990s. These topics are situated in the theoretical contexts stressing the primacy of production of gentrifiable spaces and consumption of housing by renovators. The complementarity of consensus and conflict in community formation is also noted. Five hypotheses that could be tested with 1990 census data are proposed. They deal with: the role of young households, gender, the proximity of home and workplace, residential segregation, and urban/rural similarities in community conflict. The paper ends with an acknowledgment of the need for continued theoretical and methodological diversity in the field. 相似文献
3.
Barron C.C. Mahon C.J. Thibeault B.J. Wang G. Jiang W. Coldren L.A. Bowers J.E. 《Quantum Electronics, IEEE Journal of》1995,31(8):1484-1493
We have designed, fabricated, and characterized GaAs-AlGaAs (λ=864 nm) asymmetric Fabry-Perot modulators with ≈37 GHz modulation frequency response, comparable to the fastest waveguide modulators. The modulation response saturates at high optical powers due to saturation of the excitonic absorption and heating effects, but the frequency response is independent of the incident optical intensity, since it depends only on the RC time constant, and not on the carrier transit time. The device design takes advantage of the fact that the quantum-confined Stark effect is more pronounced at some distance from the absorption edge to achieve a modulator with ⩾20 dB contrast and ≈3 dB insertion loss for ±2 V operating voltage, but only 21 fF capacitance. The DC bias used to move the operating point off the absorption edge has the additional benefits of improving the linearity and chirp of the device, as well as the saturation intensity. Here we present measurements of the modulation and photocurrent responses of the modulators, calculate the RC and transit times for the device, analyze the saturation mechanisms, and discuss the linearity and chirp of the device from the perspective of a high-speed digital optical communications system 相似文献
4.
We predicted low perceived caregiver control over caregiving failure to be related to (a) coercive or abusive parenting and (b) affective reactions to "difficult" children. On the basis of a multidimensional scaling analysis of the Parent Attribution Test (Study 1), we constructed a scale (PCF) that assessed perceived balance of control over caregiving failure (attributed control to caregivers vs attributed control to children). In Study 2, we found low PCF to predict abusiveness and nonabusive coerciveness among mothers in counseling at a child abuse agency. Additionally, we found low PCF to predict experienced annoyance/irritation among unrelated mothers interacting with children at relatively high risk for abuse (compared with their lower-risk siblings). We interpreted results as demonstrating the potential importance of low perceived control as a moderator of negative affect in response to difficult children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
We present a flexible initial framework for defining self‐motivated, self‐aware agents in simulated worlds, planning continuously so as to maximize long‐term rewards. While such agents employ reasoned exploration of feasible sequences of actions and corresponding states, they also behave opportunistically and recover from failure, thanks to their continual plan updates and quest for rewards. Our framework allows for both specific and general (quantified) knowledge and for epistemic predicates such as knowing‐that and knowing‐whether. Because realistic agents have only partial knowledge of their world, the reasoning of the proposed agents uses a weakened closed‐world assumption; this has consequences for epistemic reasoning, in particular introspection. The planning operators allow for quantitative, gradual change and side effects such as the passage of time, changes in distances and rewards, and language production, using a uniform procedural attachment method. Question answering (involving introspection) and experimental runs are shown for our particular agent ME in a simple world, demonstrating the value of continual deliberate, reward‐driven planning. Though the primary merit of agents definable in our framework is that they combine all of the aforementioned features, they can also be configured as single or multiple goal‐seeking agents and as such perform comparably with some recent experimental agents. 相似文献
6.
Multi-Class Segmentation with Relative Location Prior 总被引:2,自引:0,他引:2
Stephen Gould Jim Rodgers David Cohen Gal Elidan Daphne Koller 《International Journal of Computer Vision》2008,80(3):300-316
Multi-class image segmentation has made significant advances in recent years through the combination of local and global features.
One important type of global feature is that of inter-class spatial relationships. For example, identifying “tree” pixels
indicates that pixels above and to the sides are more likely to be “sky” whereas pixels below are more likely to be “grass.”
Incorporating such global information across the entire image and between all classes is a computational challenge as it is
image-dependent, and hence, cannot be precomputed.
In this work we propose a method for capturing global information from inter-class spatial relationships and encoding it as
a local feature. We employ a two-stage classification process to label all image pixels. First, we generate predictions which
are used to compute a local relative location feature from learned relative location maps. In the second stage, we combine
this with appearance-based features to provide a final segmentation. We compare our results to recent published results on
several multi-class image segmentation databases and show that the incorporation of relative location information allows us
to significantly outperform the current state-of-the-art. 相似文献
7.
Michael Kenteris Damianos Gavalas Daphne Economou 《Multimedia Tools and Applications》2011,54(2):241-262
This paper introduces an approach of enhancing the tourism experience by incorporating a tool that adopts a “web-to-mobile”
model into tourism websites that allows for the adaptation of personalized tourism web content to be transferred to a mobile
application hosted at users’ mobile device. These applications upon installation to mobile devices allow for browsing of adapted
multimedia content with no requirement for constant network connection. Furthermore so we convey the development experiences
of a multiplatform mobile tourist guide aimed at producing a personalized mobile guide application used in both an online
and offline modes offering services to tourists such as a personal profiling-based recommendation system, a commenting system
and location-based services. This paper focuses on the design, implementation and usability case study of a Multi-Platform
Tourist Guide system for the Municipal Council of Mytilene, Greece. 相似文献
8.
Photoelectric observations of short term light variations (shadow bands) at the 16 Feb. 1980 total solar eclipse have been made using a set of spatially separated PIN diodes. Light variations in a bandpass of 1-500 Hz were detected during the half-minutes preceding and following the total phase. Fourier analysis of the noise spectrum of the variations reveals a sharp drop-off for frequencies above 50 Hz and an overall spectrum quite similar to previously reported power spectra of stellar scintillation. This is consistent with an atmospheric origin for the shadow bands. Cross-correlations between the detector outputs are low, suggesting a short persistence time for the turbulent elements causing the patterns. 相似文献
9.
Green CS Sugarman MA Medford K Klobusicky E Daphne Bavelier 《Computers in human behavior》2012,28(3):984-994
There is now a substantial body of work demonstrating that action video game experience results in enhancements in a wide variety of perceptual skills. More recently, several groups have also demonstrated improvements in abilities that are more cognitive in nature, in particular, the ability to efficiently switch between tasks. In a series of four experiments, we add to this body of work, demonstrating that the action video game player advantage is not exclusively due to an ability to map manual responses onto arbitrary buttons, but rather generalizes to vocal responses, is not restricted to tasks that are perceptual in nature (e.g. respond to a physical dimension of the stimulus such as its color), but generalizes to more cognitive tasks (e.g. is a number odd or even), and is present whether the switch requires a goal-switch or only a motor switch. Finally, a training study establishes that the relationship between the reduction in switch cost and action game playing is causal. 相似文献
10.
Stievater T.H. Rabinovich W.S. Newman H.S. Ebel J.L. Mahon R. McGee D.J. Goetz P.G. 《Journal of microelectromechanical systems》2003,12(1):109-116
We have developed a high resolution optical technique to measure the electromechanical properties of MEMS microstructures. The technique is applied to microbridges developed for capacitive switching in coplanar radio frequency (RF) waveguides. The thin metal ground plane on the substrate and the bottom of the bridge together form a microcavity for an optical beam. The wavelength of a cavity mode is a sensitive measure of the bridge position relative to the substrate. The technique is applied to the measurement of resonances and damping times of microbridges of varying lengths. It is also used to measure dc changes in bridge height of tenths of nanometers, driven ac displacements of less than a picometer, and bridge displacement noise of hundreds of femtometers per root Hertz. This extreme sensitivity exceeds previously demonstrated optical characterization methods. 相似文献