A deliberate practice account of typing proficiency in everyday typists.

The concept of deliberate practice was introduced to explain exceptional performance in domains such as music and chess. We apply deliberate practice theory to intermediate-level performance in typing, an activity that many people pursue on a regular basis. Sixty university students with several years typing experience participated in laboratory sessions that involved the assessment of abilities, a semistructured interview on typing experience as well as various typing tasks. In line with traditional theories of skill acquisition, experience (amount of typing since introduction to the keyboard) was related to typing performance. A perceptual speed test (digit-symbol substitution) and a measure of motor abilities (tapping) were not significantly related to performance. In line with deliberate practice theory, the highest level of performance was reported among participants who had attended a typing class in the past and who reported to adopt the goal of typing quickly during everyday typing. Findings suggest that even after several years of experience engagement in an everyday activity can serve as an opportunity for further skill improvement if individuals are willing to push themselves. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Configural response learning: The acquisition of a nonpredictive motor skill.

This study examined the representational nature of configural response learning using a task that required simultaneous keypresses with 2 or 3 fingers, similar to the production of chords on the piano. If the benefits of learning are related to the retrieval of individual stimulus-response mappings, performance should depend on the frequencies of the individual responses forming each chord. Alternatively, learning may involve the encoding of configural information concerning the relationship between the chord elements. In Experiment 1, training was restricted to a subset of the 120 possible 3-element chords. Probe blocks included the practiced chords, chords composed of novel configurations of practiced elements (reconfigured), and chords that contained a new element (new). Practiced chords were performed faster than reconfigured chords, indicating learning involves the encoding of configural information. Experiment 2 showed that learning was not restricted to configurations within each hand. Experiments 3 and 4 demonstrated that learning was largely response based. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Signaling in expository hypertexts compensates for deficits in reading skill.

[Correction Notice: An erratum for this article was reported in Vol 101(2) of Journal of Educational Psychology (see record 2009-04640-014). The URL published for the supplemental material was incorrect. The correct URL is provided in the erratum.] Expository hypertexts may contain specific types of signals such as navigable topical overviews and hyperlinks that map conceptual relationships between text contents. Two experiments with German university students (N = 130, 75% female, mean age 25 years) were conducted to test the hypothesis that hypertext-specific signals particularly support learners with badly routinized reading skills in organizing and integrating complex learning materials. The experiments were based on naturalistic texts and essay-writing tasks typical for exam preparation. Learning outcomes were measured by characteristics of participants' essays (amount of knowledge, knowledge focusing, knowledge integration). In both experiments, a hypertext with a high amount of signaling yielded better learning outcomes than did a linear text for readers with a low level of skill, whereas there were no differences for readers with a high level of skill (ΔR2 from .03 to .08 for the interaction). In Experiment 2, the same interaction pattern was found for hypertext with a high versus a low amount of hypertext-specific signals (ΔR2 from .04 to .10). Moreover, a lack of signals led to less efficient navigation behavior. These results demonstrate that hypertexts equipped with hypertext-specific signals may compensate for deficits in reading skill. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

水利工程投标报价的编制

针对施工企业投标报价的重要性,从前期准备工作和编标报价等方面进行了分析,提出了投标决策及报价的技巧,以提高施工企业的中标率,从而增强施工企业的竞争力,使其在激烈的市场竞争中更好地发展。     

吴子高速公路任家沟隧道施工技术

结合任家沟隧道工程概况,介绍了环行开挖预留核心土法的施工工艺,提出了施工中应注意的问题,从而解决了黄土隧道的施工安全问题,保证了工程施工进度,对今后类似工程施工具有借鉴价值.     

阻燃镁合金的研究现状及进展

综述了阻燃镁合金的研究开发现状,尤其是Ca、Be、Zn和稀土在镁合金中的阻燃作用及其阻燃机理,指出了阻燃镁合金研究目前还存在的问题和今后的研究重点。     

丹朱岭隧道出口明洞设计

结合隧道出口滑坡区的工程地质条件,分析了滑坡特征与形成机制,并对滑坡稳定性进行了分析计算,提出在隧道明洞设计时采用滑坡治理常用的抗滑桩与明洞仰拱钢筋网相结合的方法,取得了较好的效果。     

光纤的筛选试验和寿命估算

本文讨论了长光纤的机械可靠性。简略介绍了两种光纤强度筛选的基准筛选试验设备及其方法,并从理论上分析了筛选试验后的光纤强度。最后,对筛选试验后的光纤寿命进行了估算,给出了光纤经三个等级的筛选应变后的寿命设计图。