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11.
Matthew Chamberlain 《电子设计技术》2006,13(1):96
平板液晶技术的迅猛发展让大屏幕、宽视角、高质量的视频图像得以实现。但是,随着液晶电视的屏幕变大、亮度更高,工作时所需的电压和电流也逐渐增加。而且,由于液晶电视屏幕中配置了多种供用户使用的接口,所以特别容易由于过电流和过电压的原因而出现损坏。 相似文献
12.
Begg Ian; Snider Andrea; Foley Finola; Goddard Robert 《Canadian Metallurgical Quarterly》1989,15(5):977
The generation effect occurs if people remember items they complete from fragments better than complete items they read. Four experiments investigate two questions. When does the effect occur, and why does it do so? Targets generated in related contexts are recognized better than read targets, and they are recalled better with the contexts as cues; the contexts are recognized equally well, and the relation between the context and target is not enhanced by generation. Furthermore, generated items exceed items read in pure lists even when read ones from the mixed list are no worse than the controls. The generation effect is real; it is not an artifact. However, there is nothing special about generation. Generating is a type of encoding, and like any other type of encoding, its effects are maximal on tests that require subjects to do again whatever they did at study. Generating makes targets distinctive by contrasting them with other relatives of the context, and, as a result, the targets enjoy benefits in later discriminations within their family. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
13.
It has recently been proved by Golubitsky and coworkers that in any network of coupled dynamical systems, the possible 'rigid' patterns of synchrony of hyperbolic equilibria are determined by purely combinatorial properties of the network, known as 'balanced equivalence relations'. A pattern is 'rigid' if it persists under small 'admissible' perturbations of the differential equation — ones that respect the network structure. We discuss a natural generalisation of these ideas to time-periodic states, and motivate two basic conjectures, the Rigid Synchrony Conjecture and the Rigid Phase Conjecture. These conjectures state that for rigid hyperbolic time-periodic patterns, cells with synchronous dynamics must have synchronous input cells, and cells with phase-related dynamics must have input cells that have the same phase relations. We provide evidence supporting the two conjectures, by proving them for a special class of periodic orbits, which we call 'tame', under strong assumptions on the network architecture and the symmetries of the periodic state. The discussion takes place in the formal setting of coupled cell networks. We prove that rigid patterns of synchrony are balanced, together with the analogous result for rigid patterns of phase relations. The assumption on the network architecture simplifies the geometry of admissible vector fields, while tameness rules out patterns with non-trivial local or multilocal symmetry. The main idea is to perturb an admissible vector field in a way that retains sufficient control over the associated perturbed periodic orbit. We present two techniques for constructing these perturbations, both using a general theorem on groupoid-symmetrisation of vector fields, which has independent interest. In particular we introduce a method of 'patching' that makes local changes to an admissible vector field. Having established these results for all-to-all coupled networks and tame periodic orbits we prove more general versions that require these assumptions only on a suitable quotient network. These conditions are weaker and encompass a larger class of networks and periodic orbits. We give an example to show that rigidity cannot be relaxed to hyperbolicity. We also prove, without any technical assumptions, that rigidly synchronous or phase-related cells must be input-isomorphic, a necessary precondition for the two conjectures to hold. 相似文献
14.
15.
Studied the differences in moral orientation in terms of gender specific modes of reasoning, in 2 experiments. In Exp 1, 32 Ss (aged 24–55 yrs) were read the "Heinz dilemma," and asked 3 questions regarding it. Deliberative and justificatory strategies were identified on the basis of the presence or absence of the higher level knowledge structures. In Exp 2, 40 undergraduates were presented with "Michael and Kohlberg Heinz dilemma," followed by a set of relevant questions. Male Ss preferred to apply a norm or rule in their solutions, while females rejected the application of a norm and sought alternative solutions. This was replicated in Exp 2, but the pattern was reversed with female Ss preferring to apply a norm. Males were divided in their use of either strategy indicating that although, genders differed in their judgments as to which norms or rules to apply; once adopted, norms and rules were used in similar ways. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
16.
Nick Fourikis Kimberley W. Eccleston Nick Lioutas Matthew J. Sorell 《Journal of Infrared, Millimeter and Terahertz Waves》1991,12(7):819-843
Scalar network analysers measuring the amplitude of the reflection/transmission coefficients of waveguide structures have been realised at Ka- and W-bands. Their accuracy derived by using standard mismatches is excellent at Ka- band and fairly good at W-band. To our knowledge this is the first instance where the accuracy of measurements obtained from a scalar network analyser was checked over full waveguide bands with the aid of standard mismatches. The reported reflectometers are precursors of vector network analysers based on six-port reflectometers. Methods aimed at increasing the signal-to-noise ratio (SNR) of the measurements have been developed, while proposals for improving the dynamic range of these network analysers are put forward. 相似文献
17.
Ahluwalia Jasjit S.; Nollen Nicole; Kaur Harsohena; James Aimee S.; Mayo Matthew S.; Resnicow Ken 《Canadian Metallurgical Quarterly》2007,26(2):214
Objectives: Examine the effectiveness of an intervention to increase fruits and vegetables (FV) consumption among smokers. Design: Cluster-randomized trial of 20 public housing developments; 10 randomly assigned to an FV intervention and 10 to a smoking cessation intervention. Main outcome measures: Usual (past 7 days) and past 30 days change in daily FV intake at 8 weeks and 6 months postbaseline. Results: Greater increases were seen in the FV group. At Week 8 and Month 6, the FV group had consumed 1.58 (p = .001) and 0.78 (p = .04), respectively, more daily FV servings in the past 7 days than the cessation group. At the same time points, the FV group had consumed 3.61 (p = .01) and 3.93 (p = .01), respectively, more FV servings in the past 30 days than the cessation group. Completing more motivational interviewing sessions (p = .02) and trying more recipes (p = .02) led to significantly greater increases at Month 6 among FV participants. Conclusions: Motivational interviewing counseling and lifestyle modification through trying out healthy recipes may be effective in helping a high-risk population increase their FV intake. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
18.
19.
Preliminary experiments using two chemicals (CaO, a quicklime, and a cationic nitrogen-bearing precipitant, EC-004) to remove silica from geothermal brine were undertaken at the Mokai geothermal plant, New Zealand. The brine was mixed with the reagent (CaO or EC-004). The reaction was studied from the start of the experiment (NRT, 0 min, no retaining time) and after 15 min (15RT) at 90 °C. The concentration of silica in the brine was initially 954 mg/l, and decreased linearly with increasing reagent concentration. When CaO is added, the silica concentration at 15RT was 200 mg/l lower than at NRT and became almost zero on addition of 1.5 g/l. In contrast, when EC-004 is added, the total silica concentration nearly reaches the solubility of amorphous silica at 90 °C. In order to prevent silica scaling in Mokai brines cooled to 90 °C, the CaO and EC-004 added should be individually adjusted to 0.5 g/l and 80 mg/l, respectively. 相似文献
20.
Matthew John M. Krane Frank P. Incropera 《Metallurgical and Materials Transactions A》1995,26(9):2329-2339
Numerical calculations based on a continuum model are used to examine the effects of solidification shrinkage on the redistribution
of solute in a Pb-19.2 pct Sn mixture which is convectively cooled at a sidewall. For each of three different cooling rates,
separate calculations are performed for shrinkage and buoyancy-induced flows, as well as for the combined influence of shrinkage
and buoyancy effects. The calculations reveal that flow and macrosegregation patterns are more strongly influenced by buoyancy
effects over a wide range of solidification rates. Although extremely large solidification rates yield small regions near
the chilled wall in which shrinkage-induced flows control the redis-tribution of solute, the overall effect on macrosegregation
is small relative to that associated with buoyancy. Scaling analysis of the governing equations produces reference shrinkage
and buoyancy velocities which can be used to extend the current numerical results to other binary systems. 相似文献