基于L6219芯片脉宽调制细分技术的实现

本文简要介绍了L6219芯片的功能，L6219芯片与单片机的电路设计和软件实现方法，重点介绍了利用电流细分技术实现脉宽调制的新方法。此技术已经应用在自动注射泵中，取得了良好的效果。     

溴酸钾-溴化钾消解法快速测定水中汞

采用溴酸钾 溴化钾消解法 ,通过对消解时间、消解温度及盐酸羟胺加入量的研究 ,得出较为适合的实验条件 ,可以快速测定水样中的汞 ,实际样品分析结果满意 ,RSD % =0 .76%～ 2 .7% ,CV % =92 .8%～ 1 0 1 .3%。     

构造正则表达式的最佳NFA算法的选择

介绍了工程中广泛应用的四种经典和先进的不确定有限自动机NFA的基本构造方法,它们是位置自动机Apos部分派生自动机Apd,跟随自动机Af,共同跟随集合自动机Acfs。列举大量工程实践中常用和经典的正则表达式,分别用上述自动机算法进行求解实验,对它们的运算尺寸以及与正则表达式尺寸之间的关系,列出表格分别进行比较分析,从中总结出各种自动机的构造特点和最佳应用场合。针对如何根据不同的正则表达式来选择非确定性有限自动机NFA算法提供了重要的参考依据。     

基于切割程序的双圆弧拟合算法的简化方法

本文就切割程序中如何减少程序量和算法的冗余度,提出了一种简化双圆弧拟合算法的 构造方法.     

Learning sorting algorithms through visualization construction

Recent increased interest in computational thinking poses an important question to researchers: What are the best ways to teach fundamental computing concepts to students? Visualization is suggested as one way of supporting student learning. This mixed-method study aimed to (i) examine the effect of instruction in which students constructed visualizations on students’ programming achievement and students’ attitudes toward computer programming, and (ii) explore how this kind of instruction supports students’ learning according to their self-reported experiences in the course. The study was conducted with 58 pre-service teachers who were enrolled in their second programming class. They expect to teach information technology and computing-related courses at the primary and secondary levels. An embedded experimental model was utilized as a research design. Students in the experimental group were given instruction that required students to construct visualizations related to sorting, whereas students in the control group viewed pre-made visualizations. After the instructional intervention, eight students from each group were selected for semi-structured interviews. The results showed that the intervention based on visualization construction resulted in significantly better acquisition of sorting concepts. However, there was no significant difference between the groups with respect to students’ attitudes toward computer programming. Qualitative data analysis indicated that students in the experimental group constructed necessary abstractions through their engagement in visualization construction activities. The authors of this study argue that the students’ active engagement in the visualization construction activities explains only one side of students’ success. The other side can be explained through the instructional approach, constructionism in this case, used to design instruction. The conclusions and implications of this study can be used by researchers and instructors dealing with computational thinking.     

Multiobjective optimization and multivariable control of the beer fermentation process with the use of evolutionary algorithms

INTRODUCTIONThefermentationprocesshasgreatscientificandpracticalimportance.Forseveralreasons,qua-litycontrol,forexample,itisimportanttoincludeallkindsoftechnologicaladvancesintheindustrialprocesses.Thisisthemainaimofourresearch,whichisverycomplexduetothenon-linearityofthestudiedphenomena.Themathematicalmodelsfoundinliteratureincludeonlylaboratoyconditions.Amathematicalmodelhasbeendevelopedforthebeerfermentationprocessbecauseoftheadvantagesthatitprovides.Itallowssimulatingwhatcanhappenwhe…     

CM模式的项目管理研究

CM模式是20世纪80年代开始在国际上出现的一种新的项目管理模式。对CM模式和传统的管理模式进行了比较；研究了CM模式的特点，提出了工程项目中应用CM模式的关键问题和解决方法。     

遗传算法在自动组卷应用中的分析与比较

针对遗传算法在自动组卷中的应用,总结了三种以遗传算法为基础的自动组卷解决方案,就遗传算法中的参数编码、初始群体的设定、适应度函数的设计等核心内容,进行了分析和比较,并提出结论。     

计算机在一元回归分析中的应用

探讨了利用计算机进行一元回归分析的基本方法，设计了求一元回归预测模型的算法，并用QBASIC语言编写计算机程序。