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101.
White Desiree A.; Craft Suzanne; Hale Sandra; Park T. S. 《Canadian Metallurgical Quarterly》1994,8(2):180
A. D. Baddeley, N. Thomson, and M. Buchanan (1975) suggested that articulatory rehearsal rate determines the amount of verbal material that can be maintained in working memory. In the current study, 12 children with spastic diplegic cerebral palsy (SDCP) and 38 normal children were tested on measures of articulation rate and memory span for 1-, 2-, and 3-syllable words. Across all conditions, articulation rate for the SDCP group was significantly slower than for the normal group; nonetheless, memory span was equivalent for both groups. This finding implies that covert rehearsal proceeded normally for the SDCP group, in spite of decrements in speech rate. Thus, the relationship between overt and covert rehearsal rates differs for children with SDCP compared with normal children. Findings from the current study further suggest that normal speech rates are not necessary for development of normal covert rehearsal rates. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
103.
A new controller for a digital audio amplifier with bit stream input is proposed. The proposed controller has excellent features such as wide error correction range and no limitation on the modulation index. The controller is implemented in the half-bridge class-D amplifier and performance is verified through experiments. 相似文献
104.
介绍了高频等参数感应的基本原理。以胜利油田比较典型的 3口井为例 ,详细分析了高频感应资料在划分薄夹层、确定储层流体饱和类型、评价储层电阻率空间分布等方面的应用。研究结果表明 ,高频感应具有极高的纵向分辨率和较好的径向探测特性 ,能够准确计算地层真电阻率、侵入带电阻率及侵入半径 ,通过与常规感应及薄层测井资料的对比 ,论证了高频等参数感应在测井技术应用上的优越性 相似文献
105.
The interaction of alkali metal with surfaces has been of great interest to the community of catalysis since alkali metal can play an important role as a promoter. On alkali-doped MoS2, such a promotion effect of alkali metal has been exemplified in the direct synthesis of linear alcohols from CO and H2, where the alkali-doping switches the catalyst selectivity from methanation to alcohol synthesis. This paper reviews recent high-resolution X-ray photoelectron spectroscopy experiments that have provided direct
observation of electron transfer from alkali metals to a model single crystal MoS2 and the capture of the supra-valence electrons in the subsequent oxidation reactions. 相似文献
106.
107.
This paper deals with the pricing and investment decision problem of multi-modal transportation systems in which the congestion
is a significant factor in the assessment of system costs. This study approaches this congestion pricing problem with a number
of social welfare maximization problems, all of which have the identical structure except financial constraints. One welfare
maximization problem examined in this study yields the pricing and investment decision, which can attain the first-best social
optimality for multi-modal transportation systems. Other welfare maximization problems show he second-best optimal solutions
that can address two policy questions in transportation economics, namely, the cross-subsidy between competing modes and peak-period
congestion charges on a single highway link.
Received: February 2001/Accepted: December 2001
This work was supported in part by funds from BK21 Research Division of Seoul National University for Social Infrastructure
and Construction Technology. 相似文献
108.
A recursive method based on the Kalman filtering is developed to solve inverse natural convection problems of estimating
the unsteady nonuniform wall heat flux from temperature measurements in the flow. By employing the Karhunen–Loève Galerkin
procedure that reduces the Boussinesq equation to a small set of ordinary differential equations, the computational difficulties
associated with the Kalman filtering for the partial differential equations are overcome. The present method is assessed through
several numerical experiments, and is found to yield satisfactory results.
Received 20 January 2001 / Accepted 31 May 2001 相似文献
109.
110.
In recent years, the topic of knowledge production has been widely investigated in the advanced countries. However, the process
by which knowledge is produced in the developing countries has not been fully explored or characterized. In Korea, the science
and engineering fields strongly reflect systems of knowledge production in the universities and demonstrate the dynamics of
systems of innovation for knowledge production. Through using a case study including data for knowledge production, in the
field of information and telecommunication, the following general trends were observed. Firstly, there has been a trend towards
increasing the capabilities for knowledge production, via domestic and foreign collaboration. Secondly, there has been an
increasing trend towards the diversification of knowledge sources such as university-industry, and university-public research
institutes. Finally, the establishment of a nation's knowledge base is influenced by governmental research and development
policies.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献