Towards powerful learning environments for the acquisition of problem-solving skills

It is generally agreed that acquiring thinking and problem-solving skills is nowadays a primary objective of general education. Responding appropriately to this challenge requires an answer to the following questions: 1. what does the acquisition of problem-solving skills involve, and 2. how can those abilities be fostered through systematic instruction? This contribution describes a four-step model of skilled problem-solving processes, and gives an overview of three major categories of cognitive skills involved in competent problem solving, namely, the flexible and integrated application of domain-specific knowledge, of heuristic methods, and of metacognitive skills. Furthermore, a framework is presented for the design and elaboration of powerful teaching-learning environments in which such problem-solving skills can be acquired efficiently. Two basic ideas underlying this model are: the view of learning as a constructive process, and the idea of cognitive apprenticeship as an effective and appropriate method for learning and teaching. Finally, some recent research findings supporting the educational significance of the framework are briefly reviewed.     

感官意象图式——通感的一个新认知模式

感官意象图式是由人类自身积累的感官经验和贮存在大脑中的相关生活经验抽象出来的一类独特意象图武。通感就是某一个感官域的感官意象图式，投射到其他感官经验而形成的语言现象。以认知语言学的意象图式理论为基础而提出的感官意象图式，可以用来解释通感现象的成因及过程，并提供研究通感认知模式的新方法、新视角。     

A neuromathematical model of human information processing and its application to science content acquisition

The rate of information processing during science learning and the efficiency of the learner in mobilizing relevant information in long-term memory as an aid in transmitting newly acquired information to stable storage in long-term memory are fundamental aspects of science content acquisition. These cognitive processes, moreover, may be substantially related in tempo and quality of organization to the efficiency of higher thought processes such as divergent thinking and problem-solving ability that characterize scientific thought. As a contribution to our quantitative understanding of these fundamental information processes, a mathematical model of information acquisition is presented and empirically evaluated in comparison to evidence obtained from experimental studies of science content acquisition. Computer-based models are used to simulate variations in learning parameters and to generate the theoretical predictions to be empirically tested. The initial tests of the predictive accuracy of the model show close agreement between predicted and actual mean recall scores in short-term learning tasks. Implications of the model for human information acquisition and possible future research are discussed in the context of the unique theoretical framework of the model.     

关系模式的实用分解方法案例析解

关系模式规范化的理论与实践在关系数据库原理课程中是重难点内容。本文是作者在长期教学工作和实践中总结出的关系模式的实用分解方法的教学精华。     

Strategy selection for cognitive skill acquisition depends on task demands and working memory capacity

The involvement of working memory capacity (WMC) in ruled-based cognitive skill acquisition is well-established, but the duration of its involvement and its role in learning strategy selection are less certain. Participants (N = 610) learned four logic rules, their corresponding symbols, or logic gates, and the appropriate input–output combinations in three-gate circuit patterns. Participants practiced 120 repetitions of each rule (480 total gates) over the course of 10 training blocks. Memory load varied between subjects. The confluence of task demands and individual differences in WMC (N = 518) dramatically affected speed–accuracy tradeoffs and strategic use of a computerized help function. Cluster analysis revealed five distinct groups of participants based on the combination of response accuracy, latency, and help use. Some groups with moderate to high mean WMC acquired the task with predictable performance patterns. Other groups, prevalently under a memory load and with low mean WMC, failed to learn or overused help.     

信息管理与信息系统专业链式实践教学模式探究

为了提升学生的实践能力,文章分析了信管专业传统实践教学模式存在的问题,调研了毕业生反馈的实践能力培养需求,对实践能力培养过程进行了理性分析,提出了基于时间链和任务链的实践教学改革构想.经过三年的探索与实践,构建了以导师制和研究小组为基础、以短学期实践教学和阶梯式实践任务为载体、以问题研究为主线、以实践能力提升为目标的链...     

Studies of information processing rates in science learning and related cognitive variables. II: A first approximation to estimating a relationship between science reasoning skills and information acquisition

Performance in science reasoning tasks is a significant objective in modem science instruction and increasing emphasis is being placed on the development of higher cognitive processes in science education. An empirical analysis of the relationship between science reasoning skills and the amount of information acquired during science learning as predicted by a neuromathematical model of information processing is presented. As the neuromathematical model includes a variable representing verbal ability, it is to be expected that a direct relationship exists between the amount of knowledge gained as predicted by the model and reasoning ability. The purpose of this research is to derive a formal quantitative statement for the relationship between knowledge acquisition predicted by the neuromathematical equation and scientific reasoning skills. A linear regression equation is obtained relating performance on a science reasoning task to the amount of information acquired as predicted by the neuromathematical model. This research provides a first approximation to providing a theoretical and empirical link between information processing and higher cognitive thought processes in science education.     

The effect of different sources of verbalized information on performance at a science-related cognitive task

The study simulated some aspects of science classroom verbal interaction and experimentally investigated their cognitive effects on 159 4th graders divided into 12 experimental groups by stratified random sampling. Subject-determined verbalization of correct information [2 levels] about a science oriented task situation was crossed with subjects' exposure to external sources of verbalized correct information [3 levels] about the task situation in a 2 × 3 × 2 factorial design in which sex was treated as an organismic independent variable. The dependent variable was the subjects' performance at a matrix multiple ordering task. The data were analyzed by a 3-way ANOVA using .05 alpha level. The results showed that the female subjects significantly profited from teacher-supplied information. The males seemed to make a better use of information gained directly from the materials. Teachers might therefore use a flexible approach in the classroom that would give the female students verbal hints about materials while training them to be more independent in collecting, organizing and using information.     

A multilevel study of self-beliefs and student behaviors in a group problem-solving task

Relationships among self-construal, self-efficacy, and group behaviors during a group problem-solving task with friends and acquaintances were hypothesized. The sample comprised 126 students in Grades 8–11, from 5 randomly selected government high schools, organized into 42 groups. Data collection involved self-reports and observations. Self-report data measured self-construal, self-efficacy for working with friends, and self-efficacy for working with acquaintances, and the observational data captured salient student behaviors. Data were analyzed using exploratory factor analysis and multilevel modeling. Self-efficacy for working with acquaintances was related to the development of ideas and also the critical review of ideas in groups. This study provides insights into the relatively underexplored phenomena of group work with friends and acquaintances.     

Intelligent tutoring and assessment built on an understanding of a technical problem-solving task

In this paper we describe Hydrive, an operational computer-based intelligent tutoring system built to help Air Force technicians develop generalizable skills for troubleshooting hydraulics systems. We use Hydrive as an example of how effective training and assessment is developed from a coherent understanding of a target task and how this understanding can be consistently represented in all aspects of a training/assessment instrument. We show how an organizing principle of expert behavior, active path analysis, is used to inform the design and content of the tutor's system, student and instructional models and the design of the tutor's interface. We conclude with information about Hydrive's field trial evaluation and some thoughts on knowledge acquisition and generalizability.     

The effects of part-task and whole-task instructional approaches on acquisition and transfer of a complex cognitive skill

This study was designed to investigate the effects of two instructional approaches (whole-task versus part-task) and two levels of learner prior knowledge (lower versus higher) on learner acquisition and transfer of a complex cognitive skill. Participants were 51 undergraduate pre-service teachers. In the part-task condition, a complex skill (preparing a grade book using Excel) was decomposed into a series of smaller tasks, each of which was demonstrated and practiced separately. In the whole-task condition, which was based on the 4C/ID-model (van Merriënboer 1997), learners were exposed to the entire complex skill from the beginning of the instruction and were required to practice performing a series of whole tasks throughout the unit. Results indicated that the whole-task group performed significantly better than the part-task group on a skill acquisition test and a transfer test. Possible reasons for these findings and suggestions for future research are discussed.     

A macro-level analysis of SRL processes and their relations to the acquisition of a sophisticated mental model of a complex system

In this study, we used think-aloud verbal protocols to examine how various macro-level processes of self-regulated learning (SRL; e.g., planning, monitoring, strategy use, handling of task difficulty and demands) were associated with the acquisition of a sophisticated mental model of a complex biological system. Numerous studies examine how specific micro-level SRL processes such as judgments of learning or prior knowledge activation are related to learning outcomes. However, it is also valuable to look at these processes in macro-level aggregates because efficacy and use of micro-level strategies can vary due to individual differences. Two hundred and nineteen high-school and middle-school students produced think-aloud protocols while learning with a hypermedia environment. We transcribed and coded participants’ learning sessions for the use of micro- and macro-level SRL processes. Participants’ developmental level, prior knowledge, and monitoring behaviors were associated with posttest mental model sophistication. These results illustrate that monitoring is a key SRL process when developing an understanding of a complex science topic using hypermedia.     

A dynamic model of memory for research on human information processing

This article outlines a broad theoretical framework for understanding the human information processing system as a whole. It represents one attempt to integrate the relatively static models of memory structures with the more dynamic conceptions underlying research on control and processing mechanisms. The framework embodies the synthesis of a number of conceptual orientations, including contemporary emphases on working memory, item-specific and relational information, metacognition and schema abstraction. This synthesis rests on the basic assumption that the nature of knowledge structures in human long-term memory depends on the type of information processing whereby these cognitive structures were generated.     

Age of acquisition and imageability: a cross‐task comparison

Previous research has reported an imageability effect on visual word recognition. Words that are high in imageability are recognised more rapidly than are those lower in imageability. However, later researchers argued that imageability was confounded with age of acquisition. In the current research, these two factors were manipulated in a factorial design to assess their effect in a lexical decision task and a progressive demasking task. Across both tasks, there was a clear and robust effect of age of acquisition. In contrast, the imageability effect was only evident in the progressive demasking task. Both effects are explained within the connectionist framework in terms of network plasticity and semantic feedback activation.     

Individual differences in speed of mental processing and human cognitive abilities: Toward a taxonomic model

Extensive research within the field of learning and individual differences focuses upon the relationship between general intelligence and process measures derived from elementary cognitive tasks (ECTs). This emphasis has ignored data indicating that cognitive abilities are best described by three levels (or strata). It has also been suggested that mental speed is a unitary construct, although it is more likely to have a complex structure. To address shortcomings evident in this literature, a multivariate investigation (N = 179) was conducted. Factor analysis of 25 psychometric indices gave seven factors postulated under the theory of fluid (G_f) and crystallized (G_c) intelligence. Correlations between cognitive abilities and parameters derived from 11 ECTs indicated that G_f (alone) was related to processing speed. This relationship is seemingly dependent upon experimental manipulations of task complexity. Regarding the factorial structure of mental speed, the results were unequivocal: Broad second-order factors may be derived from both ECTs and psychometric tests. These constructs are independent from abilities defined by accuracy scores and collectively define a general cognitive speed factor. Implications of these findings are discussed. It would appear that mental speed is more intricate than proposed, and that cognitive complexity (reflected in stimulus-response compatibility effects) plays a crucial role in its ontogenesis. In addition, several explanatory models linking intelligence to processing speed are untenable. It is likely that the search for a basic process of intelligence by means of mental speed frameworks (alone) is misguided.Recently, within the field of individual differences, there has been “an explosion of experimental studies into the speed of mental processes” (H.J. Eysenck 1995, p. 225). Various tasks, ranging from those paradigms assessing simple, psychomotor movements and on up through to measures of complex problem solving and psychometric test performance, have been employed (Stankov & Roberts 1997). The present study was designed to explore speed of processing constructs within a structural model of human cognitive abilities. Utilizing the evidence presented in Carroll's (1993) extensive reanalysis of the main data sets collected within the psychometric discipline this century, the structural model of cognitive abilities adopted is that known as the theory of fluid and crystallized intelligence (see Horn & Noll 1994; Stankov et al. 1995). In contrast, the mental speed measures selected for investigation in this study were chosen on the basis of both experimental and psychometric findings that rely on disparate accounts (e.g., information theory). Notably, mental speed constructs are not presently encapsulated within a single unifying model. Another major aim of the present study was to redress this imbalance by establishing a rapprochement between conceptual models of mental speed and human cognitive abilities.     

轴承滚子无损检测的信号采集与处理研究

采用激振方法,以声卡做为数据采集卡,应用MATLAB专用工具箱构建轴承滚子无损检测数据采集与处理系统,给出MATLAB环境中的程序设计和实现过程,并用实例证明该系统的有效性和实用性.