数控车床加工端面矩形螺纹

在车削加工中,螺纹的切削占有很大的比重。数控车床是目前使用最广泛的数控机床之一。与传统车床相比,数控车床比较适合于车削具有一些特殊类型螺纹的零件。本文就介绍了数控车床上端面矩形螺纹切削功能的原理,阐述了GSK980TA数控系统中端面矩形螺纹切削的加工思路。编制端面矩形螺纹切削功能的程序,并应用在数控车床切削中,效果良好。     

梯形螺纹车削训练中的几个问题

梯形螺纹车削训练中的几个问题江苏石伯军，高万君车削梯形螺纹是车工专业技能训练的重要课题之一、初学者在车削过程中，容易出现工件变形，甚至“炸刀”现象。针对这种情况．我们在指导训练中注意了以下几个问题的处理，取得了较满意的效果。注意一：刀具的选择与刃磨成...     

如何在普通螺纹精车中进行试切

螺纹车削加工是技校学生难度较高的技能训练内容,要进行多课时的训练,教师如何在学生训练中进行更高效的指导,减少物料浪费并能达到技能训练质量的要求,本文根据外圆试切的技巧提出一项能够有效提高学生螺纹车削技能的具体教学措施。     

如何在普通螺纹精车中进行试切

螺纹车削加工是技校学生难度较高的技能训练内容,要进行多课时的训练,教师如何在学生训练中进行更高效的指导,减少物料浪费并能达到技能训练质量的要求,本文根据外圆试切的技巧提出一项能够有效提高学生螺纹车削技能的具体教学措施。     

车削螺纹时常见故障及注意事项

螺纹在机器制造业中应用广泛,因而螺纹的车削是职业学校车工专业必修的一个实习课题。如何搞好螺纹车削这门技术的教学？笔者从啃刀、乱扣等问题的发生原因及处理方法和注意事项等方面进行阐述。     

常用螺纹的车削方法与问题分析

车削螺纹是车削加工中较为复杂的加工内容之一。在车削加工中,容易引起加工误差,甚至造成工件报废(如:乱牙、啃刀、尺寸超差等)。本文以普通车床上的螺纹为例,从车削方法、测量方法等方面加以分析,提出了在实际加工中规范的操作方法,从而保证螺纹的加工质量。     

浅谈中职普车实习教学中的梯形螺纹加工

在中等职业学校的普车教学中,车削梯形螺纹对于学生是一个难点,也是一个比较重要的课题,能否加工出一个合格的梯形螺纹能够反映一个人车工水平的高低。分层车削法加工梯形螺纹对于中职学生来说是简单易懂,且安全有效的方法。     

车螺纹等车削加工仿真动画的研制

本文介绍了车螺纹等车削加工仿真动画的设计思路,着重阐述了车螺纹仿真动画的制作过程与技巧。     

论车工实习教学存在的问题及其对策

车工实习课是一门培养学生掌握中级车工操作技能、技巧的课程,内容包括外圆车削、平面车削、镗孔、割槽、三角螺纹车削、梯形螺纹车削等.另外,还包括常用设备的维护和保养、刀具的刃磨、修理一般的机床故障和试车调整等.近年来,车工专业"应会"考试的内容日益狭窄且与教学大纲脱离,主要表现在应会考试及专业技能比赛比较重视外圆、镗孔、螺纹的高精度.     

锥度面上车削圆弧牙型螺纹

在近几年的职业技能竞赛数控车项目比赛中异形螺纹的加工成为一个常考点,由于此类螺纹的加工借助CAM软件编程无法完成,因此有不少选手对于此类异形螺纹的程序编制思路和利用宏程序编程存在一定的困难,难以完成,影响竞赛成绩。本文以利用外圆偏刀在锥度面上车削圆弧牙型螺纹为例对异性螺纹的宏程序编制的思路及程序的编制加以分析。     

如何训练学生车削梯形螺纹

在训练学生车削梯形螺纹时,要注意车刀的选择与刃磨、车刀的装夹、工件的装夹,要调整车床、选择工艺参数、确定工步。梯形螺纹的测量方法主要包括综合测量法和三针测量法。在车削梯形螺纹时,教师应加强巡回指导。     

Questioning and the quality of knowledge constructed in a CSCL context: a study on two grade-levels of students

This paper aims to study the relationship between questioning and the quality of knowledge constructed in a CSCL context. In previous studies, different units of analysis are employed and the patterns of relationships are not consistent for different age groups. The analytic units of a thread, an individual, and a group are employed in this study, and two grades of students (grade 6 and grade 10) are investigated. At the thread level, we aim to examine to what extent questioning can be a mechanism for knowledge advancement, and we find that the tenth-graders are capable to advance knowledge through questioning, while for the sixth-graders, more facilitation seems to be needed. At the individual level, we find that for the sixth-graders, those asking good questions are likely to express high-level explanations, suggesting that individual competence plays an important role in advancing knowledge among these younger students. For the tenth-graders, a “division of labor” is observed that good questions are generated by some students while high-level explanations by others. At the group level, a high and positive correlation is found for both grades. The findings suggest further research is needed to examine other possible mechanisms for knowledge advancement in online collaborative discourse.     

Changing the Name of a Major University: A Case Study and How-To Guide

There is nothing more exciting for a school than taking on a new name that is more reflective of what the institution has become. Many schools have changed names from “College” to “University” or have been renamed for prominent individuals. On August 28, 2005, Southwest Missouri State University officially became Missouri State University. This change was 20 years in the making and did not happen without a tremendous amount of effort on the part of administrators, faculty, students, alumni, and many elected officials at all levels of government. Though seemingly a simple thing, implementing the name change was anything but. This case study explains the steps taken to complete the transition, including the important branding decisions made along the way. It also provides a detailed guideline for other schools facing similar challenges.     

The Effect of Worked Examples When Learning to Write Essays in English Literature

Worked examples, commonly used in technical domains, are rarely used in language areas such as English literature. In 3 experiments, Korean university students for whom English was a foreign language received worked examples intended to facilitate problem solving in the ill-structured domain of English literature. During the learning phase, half of the students were presented conventional essay questions that they were asked to answer. The other half of the students were presented the same questions along with model answers that they were asked to study, followed by similar questions that they had to answer themselves. All students then were asked to answer retention, near and far transfer tests. Relatively more knowledgeable students were assigned to Experiment 1 than to Experiment 2, who, in turn, were more knowledgeable than were the students in Experiment 3. Results indicated that the effectiveness of worked examples increased with decreasing student knowledge.     

高职高专生主观幸福感与网络欺凌的关系研究

采用总体幸福感量表与网络欺凌量表,就连云港市高职高专生主观幸福感与网络欺凌之间的关系进行调查.调查样本为连云港市两所高职高专院校的522名学生.结果显示:(1)连云港高职高专生网络欺凌在人口学变量上差异并不明显,但在得分上男生高于女生,完整家庭、重组家庭、单亲家庭得分依次递增,年级依次递增.(2)连云港高职高专生主观幸...     

SINUMERIK数控系统加工螺纹的编程方法

螺纹加工是零件加工工艺中常见的工序。随着机械加工自动化程度的提高,数控机床的使用越来越普遍,要求数控机床也应具有螺纹加工的功能。在介绍数控车床、铣床及加工中心上螺纹加工原理的基础上,着重介绍SINUMERIK数控系统加工不同螺纹的各种编程方法,工艺特点和机床操作的要求。     

超以象外 得其环中——潘莉萍老师“交谈”课例评说

"两课"评比活动产生了不少好课例,也为职业学校教学改革提供了学习的楷模。江苏省第二届文化课程语文学科组"两课"评比中,潘莉萍老师的"交谈"获得示范课。该课例知识教学、整体架构、活动体验与合作学习设计新颖,匠心独具,可圈可点,值得学习借鉴。     

STRATEGIES FOR SOLVING THREE FRACTION-RELATED WORD PROBLEMS ON SPEED: A COMPARATIVE STUDY BETWEEN CHINESE AND SINGAPOREAN STUDENTS

This paper presents the results obtained from a study comparing the strategies used by 1,070 Chinese students and 1,002 Singaporean students from primary grade 6 to secondary year 2 in solving three fraction-related problems. It is part of the author's Ph.D. study, which involves more word problems on speed. The Chinese students performed better than the Singaporean students on two of the three problems, while the Singaporean students performed better than the Chinese students on the other. The strategy analyses reveal that the Chinese students used the traditional methods like arithmetic and algebraic strategies more frequently than the Singaporean students, whereas the Singaporean students used the model and unitary methods more frequently than the Chinese students. Implications for the teaching and learning of word problems on speed, as well as problem solving, are also provided.     

On the Benefits of Seeking (and Avoiding) Help in Online Problem-Solving Environments

Seeking the right level of help at the right time can support learning. However, in the context of online problem-solving environments, it is still not entirely clear which help-seeking strategies are desired. We use fine-grained data from 38 high school students who worked with the Geometry Cognitive Tutor for 2 months to better understand the associations between specific help-seeking patterns and learning. We evaluate how students’ help-seeking behaviors on each step in a tutored problem are associated with their success on subsequent steps that require the same skills. Analyzing learning at the skill level allows us to compare different help-seeking patterns within a single student, controlling for between-student variations. Overall, asking for help on challenging steps is associated with productive learning, and overusing help is associated with poorer learning. However, contrary to many help-seeking theories, avoiding help (and failing repeatedly) is associated with better learning than seeking help on steps for which students have low prior knowledge. These results suggest that novice learners may benefit from engaging in solution attempts before they can make sense of given assistance. Methodological benefits for using local measures of learning are discussed, and comparisons are drawn to other forms of productive failure in problem solving.     

河南省高校运动会增设趣味性项目必要性研究

随着素质教育的不断改革,体育在高校中的地位越来越不容忽视,高校运动会更是扮演着重要的角色。高校运动会应淡化竞技,注重兴趣培养,促进更多的学生参与到运动中。增设趣味性项目将会推动高校运动会的发展,提升高校学生的整体素质。