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81.
Matt Smith 《电子产品世界》2005,(11):77-78
减小封装尺寸和提高性能的双重要求向便携式系统设计工程师提出了解决散热管理问题的严峻挑战.提高性能通常通过提高时钟频率和提高集成度来实现,但是这两种做法都会引起功耗增加.另外封装尺寸减小势必增加了器件的散热困难.因此,便携式设备的散热问题因受重量、通风配置、防风雨和其它因素的限制而进一步加重. 相似文献
82.
Matt Bishop 《Software》1987,17(10):729-739
Profiling under UNIX is done by inserting counters into programs either before compiling, during compiling or during assembly. A fourth type of profiling involves monitoring the execution of a program, and gathering relevant statistics during the run. This paper looks at this method and an implementation of it, and discusses its advantages and disadvantages. 相似文献
83.
Matt Donachie 《Journal of Materials Engineering and Performance》2003,12(2):119-120
84.
Matt Chamberlain 《电子制作.电脑维护与应用》2005,(9):32-32
Raychem快速动作表面贴装熔断器是一种应用广泛的新型元件。该熔断器可为使用低于63V直流电源的系统提供过流保护,并有助于开发更可靠的高性能电子产品。目前已应用于手提电脑、多媒体装置。手机等便携式电子产品。 相似文献
85.
King Serena M.; Burt S. Alexandra; Malone Stephen M.; McGue Matt; Iacono William G. 《Canadian Metallurgical Quarterly》2005,114(4):587
The authors examined genetic and environmental contributions to stability and change in heavy drinking from late adolescence to young adulthood in a sample of 1,152 twin pairs. In men, heavy drinking was similarly heritable at ages 17 (h2 = .57) and 20 (h2 = .39), and its stability owed primarily to common genetic factors. In women, heavy drinking was less heritable than in men at ages 17 (h2 = .18) and 20 (h2 = .30) and its stability was primarily due to enduring shared environmental influences. P3 amplitude, an event-related brain potential marker of alcoholism risk, was less predictive of heavy drinking in women than in men, providing further support for the proposition that biological factors have less impact on heavy drinking in young adult women than in young adult men. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
86.
Matt Harrington Michael Lin Kerstin N. Nordstrom Wolfgang Losert 《Granular Matter》2014,16(2):185-191
Many recent advances in the study of granular media have stemmed from the improved capability to image and track individual grains in two and three dimensions. While two-dimensional systems readily yield both translational and rotational motion, a challenge in three-dimensional experiments is the tracking of rotational motion of isotropic particles. We propose an extension of the refractive index matched scanning technique as a method of measuring individual particle rotation. Initial measurements indicate that shear-driven rotational motion may stem from gear-like motion within the shear zone. 相似文献
87.
Vogel R Willmott G Kozak D Roberts GS Anderson W Groenewegen L Glossop B Barnett A Turner A Trau M 《Analytical chemistry》2011,83(9):3499-3506
The use of a "size-tunable" polyurethane resistive pulse sensor for quantitative sizing of nano- and microparticles is presented. A linear relationship, as first suggested by Maxwell, between particle volume and change in electric resistance across the pore was observed. Particle sizes were quantified for a given size-tunable membrane, by first creating a linear calibration curve to a series of monodisperse carboxylated polystyrene particles of various diameters and then applying this curve to calculate the size of "unknown" nanoparticles. The diameters of a selection of synthetic and biological particles, being PMMA and nonfunctionalized polystyrene particles, along with biological nanoparticles (adenovirus) were calculated using this methodology. Calculated particle diameters and coefficients of variation were shown to be in good agreement with both transmission electron microscopy and dynamic light scattering results. 相似文献
88.
风景园林师通常更倾向以季相特征的方式去理解植物
随时间发生的变化。认为从蒂莫西·莫顿(Timothy Morton)
的时间推移(time lapse)概念中汲取灵感,并通过时间性的
概念来思考植物,将有机会改变风景园林师认知和设计植物的
方式。虽然这种种植设计方法不直接指向一种形式(form),
但它确实与当前称为生态主义或自然主义的种植概念有许多相
似之处。调查了2个建成项目——格伦斯通博物馆(Glenstone
Museum)和布鲁克林大桥公园(Brooklyn Bridge Park),以
理解时间性是如何影响设计的。最后,提出了通过慢速植物知
识(slow plant knowledge)引导设计的新发展趋势 相似文献
89.
Reports an error in "Learning myopia: An adaptive recency effect in category learning" by Matt Jones and Winston R. Sieck (Journal of Experimental Psychology: Learning, Memory, and Cognition, 2003[Jul], Vol 29[4], 626-640). On page 633, Table 2, the values in columns (T, P) and (P, T) in the dual condition row incorrectly read .10 and .90, respectively. The correct values are .90 and .10, respectively. (The following abstract of the original article appeared in record 2003-06626-013.) Recency effects (REs) have been well established in memory and probability learning paradigms but have received little attention in category learning research. Extant categorization models predict REs to be unaffected by learning, whereas a functional interpretation of REs, suggested by results in other domains, predicts that people are able to learn sequential dependencies and incorporate this information into their responses. These contrasting predictions were tested in 2 experiments involving a classification task in which outcome sequences were autocorrelated. Experiment 1 showed that reliance on recent outcomes adapts to the structure of the task, in contrast to models' predictions. Experiment 2 provided constraints on how sequential information is learned and suggested possible extensions to current models to account for this learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.
JP Hugnot M Salinas F Lesage E Guillemare J de Weille C Heurteaux MG Mattéi M Lazdunski 《Canadian Metallurgical Quarterly》1996,15(13):3322-3331
Outward rectifier K+ channels have a characteristic structure with six transmembrane segments and one pore region. A new member of this family of transmembrane proteins has been cloned and called Kv8.1. Kv8.1 is essentially present in the brain where it is located mainly in layers II, IV and VI of the cerebral cortex, in hippocampus, in CA1-CA4 pyramidal cell layer as well in granule cells of the dentate gyrus, in the granule cell layer and in the Purkinje cell layer of the cerebellum. The Kv8.1 gene is in the 8q22.3-8q24.1 region of the human genome. Although Kv8.1 has the hallmarks of functional subunits of outward rectifier K+ channels, injection of its cRNA in Xenopus oocytes does not produce K+ currents. However Kv8.1 abolishes the functional expression of members of the Kv2 and Kv3 subfamilies, suggesting that the functional role of Kv8.1 might be to inhibit the function of a particular class of outward rectifier K+ channel types. Immunoprecipitation studies have demonstrated that inhibition occurs by formation of heteropolymeric channels, and results obtained with Kv8.1 chimeras have indicated that association of Kv8.1 with other types of subunits is via its N-terminal domain. 相似文献