双壁钢围堰吸泥下沉、清基及水下封底过程中有关问题的处理办法

系统概述了介绍芜湖长江大桥11号主墩双壁钢围堰吸泥下沉、清基及水下封底过程和应注意的事项及有关问题的解决办法。     

Three dimensional couette flow and heat transfer through a porous medium with variable permeability

This paper reports research on the effects of variations in injection velocity and permeability on the heat transfer and flow through a highly porous medium between two horizontal parallel plates situated at constant distance with constant suction by the upper plate. Due to this type of variation in injection velocity and in permeability the flow becomes three dimensional. The governing equations are solved by adopting complex variable notations to obtain the expressions for the velocity and temperature field. The skin-friction along the main flow direction and rate of heat transfer are discussed with the help of graphs.     

我国"民工荒"问题的深层次研究

在农村剩余劳动力存量超过1.5亿的中国,从2004年初直至2005年,在沿海地区的劳动密集型行业竟然出现了“民工荒”。虽出人意料,但又有其经济、社会、文化及政策方面的必然原因。它已经并将继续在一定程度上影响中国经济社会的发展。提高农民工待遇、企业进行转型或转移、创造良好制度环境、转变我国经济发展战略是应对“民工荒”的有效措施。     

浅谈大学英语写作教学的现状及改革

英语写作是大学英语统考中得分较低的一项。然而作为一种书面形式的主动性技能,英语写作却往往能比较客观地反映出英语学习者的语言能力的高低。针对大学英语作文内容空洞贫乏,写作知识与技巧的缺乏,语言表达错误等问题,我们必须实施英语测试、教学内容与方式的一系列的改革,从而能有效地改进大学英语写作教学,提高学生英语写作的技能。     

大学英语词汇教学方法初探

词汇是组成语言的基本单位。词汇教学是英语教学的重要方面,尤其在大学阶段要求英语词汇量大幅度增加。如何帮助学生有效地扩大词汇量成为许多教师需要解决的首要问题之一。针对这一现象,提出了相关的教学方法。     

新课改背景下的高中物理课堂教学设计

在我市新课程实施的初期阶段,笔者根据自己的教学经验,结合新课程所倡导的一些基本理念,对课堂教学设计进行了改进,以期与广大一线教师进行交流。     

Expertise Differences in the Comprehension of Visualizations: a Meta-Analysis of Eye-Tracking Research in Professional Domains

This meta-analysis integrates 296 effect sizes reported in eye-tracking research on expertise differences in the comprehension of visualizations. Three theories were evaluated: Ericsson and Kintsch’s (Psychol Rev 102:211–245, 1995) theory of long-term working memory, Haider and Frensch’s (J Exp Psychol Learn Mem Cognit 25:172–190, 1999) information-reduction hypothesis, and the holistic model of image perception of Kundel et al. (Radiology 242:396–402, 2007). Eye movement and performance data were cumulated from 819 experts, 187 intermediates, and 893 novices. In support of the evaluated theories, experts, when compared with non-experts, had shorter fixation durations, more fixations on task-relevant areas, and fewer fixations on task-redundant areas; experts also had longer saccades and shorter times to first fixate relevant information, owing to superiority in parafoveal processing and selective attention allocation. Eye movements, reaction time, and performance accuracy were moderated by characteristics of visualization (dynamics, realism, dimensionality, modality, and text annotation), task (complexity, time-on-task, and task control), and domain (sports, medicine, transportation, other). These findings are discussed in terms of their implications for theories of visual expertise in professional domains and their significance for the design of learning environments.     

Facilitating Understanding of Movements in Dynamic Visualizations: an Embodied Perspective

Learners studying mechanical or technical processes via dynamic visualizations often fail to build an accurate mental representation of the system’s movements. Based on embodied theories of cognition assuming that action, perception, and cognition are closely intertwined, this paper proposes that the learning effectiveness of dynamic visualizations could be enhanced by grounding the movements of the presentation in people’s own bodily experiences during learning. We discuss recent research on embodied cognition and provide specific strategies for how the body can be used to ground movements during the learning process: (1) making or observing gestures, (2) manipulating and interacting with objects, (3) using body metaphors, and (4) using eye movements as retrieval cues. Implications for the design of dynamic visualizations as well as directions for future research are presented.     

Function oriented service composition modeling

Formal models for service composition have been proposed with the variation of the requirements of service developers. Some famous models have provided checking and verification techniques and tools for the behavior of service composition. These models generally focus much on the message flow of web services and neglecting the data contained in the exchanged messages among services, which restrict the application range of these models and also the web service techniques. As new kind of services with different protocols and communication methods have appeared, it is needed to model service composition from a new view which is adapted to the new development in service area. In this paper we offer a function oriented model of service composition which treats the composite service as a software system and specify the function of services which can be directly used to the realization by service providers.