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431.
A Fast Parallel Algorithm for Convex Hull Problem of Multi-Leveled Images   总被引:1,自引:0,他引:1  
In this paper, we propose a parallel algorithm to solve the convex hull problem for an (n×n) multi-leveled image using a reconfigurable mesh connected computer of the same size as a computational model. The algorithm determines parallely the convex hull of all the connected components of the multileveled image. It is based on some geometric properties and a top-down strategy. The complexity of the algorithm is O(logn) times. Using some approximations on the component contours, this complexity is reduced to O(logm) times where m is the number of the vertices of the convex hull of the biggest component of the image.This complexity is reached thanks to the polymorphic properties of the mesh where all the components are simultaneously and separately processed.  相似文献   
432.
Action potentials and single twitches from papillary muscles were acquired and analyzed in real-time using a programmable digitizer and a microcomputer. This combination provides greater control and flexibility during data acquisition than standard analog-to-digital converters. The present system was designed to facilitate evaluation of experimental drugs. However, the combination of a programmable digitizer and a laboratory microcomputer can be applied to a variety of applications in biomedical research.  相似文献   
433.
This paper describes an efficient Web page change detection system based on three optimizations that were implemented on top of the Hungarian algorithm, which we employ to compare trees that correspond to HTML Web pages. The optimizations attempt to stop the comparator algorithm that employs this O(n3) algorithm before it completes all its iterations based on criteria having to do with properties of HTML and heuristics. Analysis and experimental results prove the effectiveness of these optimizations and their ability to render O(n2) performance, where n denotes the number of nodes in the tree. A complete system was implemented and used to carry out the performance experiments. This system includes functionalities and interfaces for processing user requests, fetching Web pages from the Internet, allowing users to select zones in Web pages to monitor, and highlighting changes on the Web pages being monitored  相似文献   
434.
435.

Background

In recent years, the importance of emotions in learning has been increasingly recognized. Applying emotional design to induce positive emotions has been considered a means to enhance the instructional effectiveness of digital learning environments. However, only a few studies have examined the specific effects of emotional design in game-based learning.

Objectives

This quasi-experimental study utilized a value-added research approach to investigate whether emotional design applied to scaffolding in a game-based learning environment improves learning and motivational outcomes more than emotionally neutral scaffolding.

Methods

A total of 138 participants, mean age of 11.5 (SD = 0.73) participated in the study. A total of 68 participants played the base version of a fraction learning game (Number Trace), where scaffolding was provided with emotionally neutral mathematical notations, and 70 participants played the value-added version of the game using emotionally designed animated scaffolding agents. Pre-and post-tests were used to measure conceptual fraction knowledge and self-reported measures of situational interest and situational self-efficacy to evaluate motivational outcomes.

Results and Conclusions

Our results indicate that the emotional design applied to scaffolds can improve the educational value of a game-based learning environment by enhancing players' situational interest and situational self-efficacy. However, although the intervention improved the participants' conceptual fraction knowledge, there was no significant difference between the scaffolding conditions in participants' learning outcomes.

Takeaways

The results suggest that emotional design can increase the educational impact of game-based learning by promoting the development of interest, as well as improving self-efficacy.  相似文献   
436.
In our constant search for new successors of agomelatine, we report herein a new series of compounds resulting from bioisosteric modulation of the naphthalene ring. The isoquinoline and tetrahydroisoquinoline derivatives were synthesized and pharmacologically evaluated. This isosteric replacement of the naphthalene group of agomelatine has led to potent agonist and partial agonist compounds with nanomolar melatonergic binding affinities. Overall, the presence of a nitrogen atom was accompanied with a decrease in the binding affinity toward both MT1 and MT2 and the loss of 5HT2C response, especially for tetrahydroisoquinoline in comparison with the parent compound. Interestingly, due to the presence of this nitrogen atom, a notable improvement in the pharmacokinetic properties was observed for all compounds.  相似文献   
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