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排序方式: 共有593条查询结果,搜索用时 15 毫秒
1.
在磁定位技术应用过程中,为解决数据处理过程复杂、计算量大导致实时性无法满足问题,利用FPGA的并行结构,设计实现了一种基于FPGA平台的磁定位方案。实验结果表明,磁矩为0.1255[A?m2]的永磁体在距离磁传感器高度在20cm以内时,定位精度能达到毫米级,定位速度比通用计算机提升了一倍以上,可以满足绝大多数实时性要求,更有利于永磁体定位技术产业化,应用前景广阔。 相似文献
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Studies suggest that people who cheat on a test overestimate their performance on future tests. Given that erroneous monitoring of one's own cognitive processes impairs learning and memory, this study investigated whether cheating on a test would harm monitoring accuracy on future tests. Participants had the incentive and opportunity to cheat on one (Experiments 1, 2, and 3, with N = 90, 88, and 102, respectively) or two (Experiment 4, N = 214) of four general-knowledge tests. Cheating produced overconfidence in global-level performance predictions in Experiment 2 (Cohen's d ≥ 0.35) but not in Experiments 1 or 4. Also, cheating did not affect the absolute or relative accuracy of item-level performance predictions in Experiments 3 or 4. A Bayesian meta-analysis of all experiments provided evidence against cheating-induced overconfidence in global- and item-level predictions. Overall, our results demonstrate that people who cheat on tests accurately predict their performance on future tests. 相似文献
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For regulation of text learning to be effective, students need to accurately monitor their text comprehension. Similarly, to provide adaptive instruction, teachers need to accurately monitor and regulate students’ text comprehension. Performing generative activities prior to monitoring has been suggested to provide students with diagnostic cues, improving monitoring accuracy; an open question is whether this would also help teachers. We investigated whether two generative activities, diagram completion and diagram drawing, improved secondary education students’ (n = 248) monitoring and regulation accuracy of text comprehension (Experiment 1) and whether viewing students’ diagrams improved teachers’ (N = 18) monitoring and regulation of students’ text comprehension (Experiment 2). Students’ monitoring and teachers’ regulation accuracy was higher in the diagramming conditions than in the no-diagramming condition. Students and teachers used diagnostic cues when judging students’ text comprehension: Improving students’ monitoring and teachers’ regulation of students’ text comprehension relies on improving accessibility of diagnostic cues. 相似文献
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新药物研发时间长、成本高,但成功率低,为了提高收益比,药物重定位即旧药新用受到了广泛关注。从临床和实验角度鉴定药物的新用途需要耗费大量人力和物力,从计算角度预测药物新用途成为研究热点;并且,随着药物和疾病相关的大量多层次组学数据积累,通过挖掘药物相关数据鉴定药物新用途成为可能。重点挖掘药物化学结构、药理性质、药物靶蛋白功能、疾病表型等数据得到相应特征,并将这些药物疾病特征进行整合,再将特征输入XG-BOOST模型进行预测。实验结果表明,该方法准确率达87.9%,较逻辑回归、随机森林具有更高的预测精度。 相似文献
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焊接机器人工装组夹及产品复现在生产中是极为重要的,文章针对焊接机器人对工装精确度的要求,采用棋盘方格定位法和复现工艺,实现了焊接工装和机器人重复定位精度的要求,在多种产品上得到应用推广。 相似文献
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Systematic Comparison of Decision Accuracy of Complex Compensatory Decision Rules Combining Multiple Tests in a Higher Education Context 下载免费PDF全文
Iris E. Yocarini Samantha Bouwmeester Guus Smeets Lidia R. Arends 《Educational Measurement》2018,37(3):24-39
This real‐data‐guided simulation study systematically evaluated the decision accuracy of complex decision rules combining multiple tests within different realistic curricula. Specifically, complex decision rules combining conjunctive aspects and compensatory aspects were evaluated. A conjunctive aspect requires a minimum level of performance, whereas a compensatory aspect requires an average level of performance. Simulations were performed to obtain students' true and observed score distributions and to manipulate several factors relevant to a higher education curriculum in practice. The results showed that the decision accuracy depends on the conjunctive (required minimum grade) and compensatory (required grade point average) aspects and their combination. Overall, within a complex compensatory decision rule the false negative rate is lower and the false positive rate higher compared to a conjunctive decision rule. For a conjunctive decision rule the reverse is true. Which rule is more accurate also depends on the average test reliability, average test correlation, and the number of reexaminations. This comparison highlights the importance of evaluating decision accuracy in high‐stake decisions, considering both the specific rule as well as the selected measures. 相似文献
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介绍BP神经网络的结构及相关算法,并通过实验比较不同情况下对BP神经网络的收敛速度与分类精度的影响。实验表明,合适的参数设置能提高BP神经网络算法的分类精度。 相似文献
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How accurate are teachers’ first impressions and what moderates the degree of first impression accuracy? In previous teacher judgment accuracy research, teachers judged students who were well-acquainted to them, focusing on single traits. Here, we follow the zero-acquaintance paradigm and apply the Social Accuracy Model (SAM; Biesanz, 2010) to examine teachers’ first impressions regarding students’ personality profiles. Three groups of perceivers (student teachers, experienced teachers and psychology students; N = 285) rated students’ (N = 10) academic self-concept, intrinsic motivation and intelligence based on brief videos. SAM analyses revealed that teachers were accurate regarding the average students’ profile of characteristics (normative accuracy), but were not successful at detecting students' unique personality profiles (distinctive accuracy). Moreover, likeable students and those evaluated as more physically attractive were perceived with higher normative accuracy. Personality similarity and teaching experience were unrelated to accuracy. Implications for teacher judgment accuracy research and educational practice are discussed. 相似文献