Evaporation Erosion During the Relay Contact Breaking Process Based on a Simplified Arc Model

Evaporation erosion of the contacts is one of the fundamental failure mechanisms for relays. In this paper, the evaporation erosion characteristics are investigated for the copper contact pair breaking a resistive direct current （dc） 30 V/10 A circuit in the air. Molten pool simulation of the contacts is coupled with the gas dynamics to calculate the evaporation rate. A simplified arc model is constructed to obtain the contact voltage and current variations with time for the prediction of the current density and the heat flux distributions flowing from the arc into the contacts. The evaporation rate and mass variations with time during the breaking process are presented. Experiments are carried out to verify the simulation results.

The Arc Model in SiO_2 Current-limiting Fuse

An arc model in SiO2 current-limiting fuse has been put forward. Through taking into account the comprehensive effects such as: fundamental action process among particles of arc column, geometrical and external circuit characteristics of arc column, physical procedure in arc column and in cathode and anode, and power equilibrium in arc column plasma et al., parameters such as the temperature, length, volumn, pressure, arc voltage, arc current et al. in the arc column can be obtained by the model. In view of the serious nonlinearity and huge difference among parameters in the equation set of the model, via analysis on these equations, two solution methods for the equations of the model have been presented with a basic accordance between calculated results and test results.

Simulation of Fault Arc Using Conventional Arc Models

Conventional arc models are usually used to research the interaction between switching arc and circuit. It is important to simulate the fault arc for arc flash calculations, choice of electrical equipments and power system protection. This paper investigates several conventional arc models for calculating the fault arcing current. Simulation results show that conventional arc models can be used to simulate the fault arc if the parameters of arc models are given properly. This paper provides the parameters of 5 popular arc models and describes the simulation results of the fault arc.

The Application of ARCS Motivation Model in Online College English Class

Since the epidemic,online classes have been a common practice,and learning motivation plays a key role in the efficiency of the online English,which should not be underestimated in improving online foreign language teaching.This paper discusses how to effectively apply ARCS motivation model in online English teaching design with examples of college English textbooks,so as to motivate students and improve students’online classroom efficiency by improving their learning motivation.

ARCS动机模型下右玉精神融入高校思政教育探析

右玉精神蕴涵的深厚思想精髓是我国高校思想政治教育的重要资源和优秀教材,能够很好地帮助当代青年学生提升自身政治素养和传承艰苦奋斗的精神。文章基于ARCS动机模型,从“注意、关联、信心、满意”四个环节,归纳总结了右玉精神融入高校思想政治教育过程中面临的现实困境,如学习氛围不浓且教学模式陈旧、学习内容机械生硬、教学手段陈旧单调、学习效果不佳学生满意度不高,尝试提出营造氛围改变教学模式、与时俱进设计教学内容、完善教学评价反馈机制、情景教学并注重成果展示四个解决路径。

基于TARGET融合ARCS动机模型的应用统计学课程教学改革研究

学生的学习动机直接关系到课程教学目标的达成,激发学习动机是推动课程教学改革的应有之义。将TARGET和ARCS学习动机模型引入应用统计学课程教学,分析当前教学中存在的动机问题,提出有效激发学生动机的教学方案和实践策略,结果既可促进应用统计学课程教学质量提升,也可为其他相似课程教学设计提供参考借鉴。

ARCS模型视角下武术游戏化教学质量评价方法研究

研究ARCS模型视角下武术游戏化教学质量评价方法,促进武术教学质量良性发展。设计ARCS模型武术游戏化教学质量评价结构,通过定义模块激发学生学习武术兴趣,设计模块依据学生兴趣设立武术游戏化课堂,预设与学生相对应武术闯关游戏,通过在游戏中学习武术专业知识,激发模块通过武术游戏化课堂的学习环境、武术知识建立学生武术学习自信心;评价模块通过构建教学质量评价指标体系,采用模糊综合评价算法,依据各指标获取教学质量综合评价结果,依据评价结果不断完善教学设置,提升学生武术学习满意度。实验说明:该方法设计武术游戏化教学可提升中小学学生武术学习兴趣度,增加武术课堂教学效果,同时该方法能客观表达武术教学质量评价结果。

基于ARCS的ASD儿童绘本角色设计研究

目的为提升ASD儿童情绪学习动机,探究不同角色形象在基本情绪学习中的激发作用,以绘本角色造型为切入点,为绘本角色设计和干预训练提供参考。提出一种基于ARCS动机模型的角色设计研究方法。方法首先,结合ARCS动机维度,建立了一套适用于绘本角色研究的指标体系。在文献研究的基础上,筛选出7项代表性眼动指标和1项情绪匹配数据,并利用眼动仪收集这些指标的实验数据;其次,采用熵权法计算眼动实验客观指标的权重,并使用逼近理想解法(TOPSIS)确定三大角色样本类型的综合排序。结果研究发现,与其他类型的角色相比,在ASD儿童中,器物角色的动机反馈效果更佳,并且这几类角色对ASD儿童的眼动指标都有不同程度的影响,因此每个角色的干预效果也不尽相同。结论将ARCS动机理论模型引入绘本角色设计中,结合眼动实验解析动机策略与角色特征元素之间的关联性,能更有效地改善干预训练中缺乏学习动机的情况;建立评价体系有助于为后续相关设计提供研究思路。

基于ARCS模型的摄影教育游戏设计研究

文章旨在设计一款基于ARCS模型的摄影教育游戏,来提升非艺术生在公共摄影课程中的学习动机。作者团队对ARCS的4个要素进行了深入分析,并将它们融入游戏的设计策略中。分别对游戏的视觉、教学内容、奖励机制和交互模式进行设计实践。最后将游戏投入摄影课堂中做了效果对比测试。结果显示此教育游戏对提升学生的学习动机具有显著作用。文章为模拟摄影教育游戏的设计提供了新的思路,更为提升非艺术生的摄影教学打开了更多的创新空间。

ARCS动机模型在工科课程案例教学中的应用研究——以“船舶减振降噪技术”课程为例

学生的动机水平是自主学习的重要因素。针对“船舶减振降噪技术”课程知识点繁多且庞杂、与工程实际联系紧密的特点,提出利用ARCS动机模型指导案例教学设计的方法。以“声短路”影响测定实验课为例,通过案例内容优化提升学习注意力,通过职业发展关联提升学习相关性,通过小组分工合作提升学习自信心,通过学习评价设计提升学习满意度。教学实践结果表明,该方法能有效激发和维持学生内生动力,提升教学效果,强化学生的职业素养和能力。

基于ARCS动机模型的高校机械制图课程教学实践探究

随着高校教育的不断发展,教学质量和教学效果已经成为教育领域关注的焦点。机械制图作为一门重要的专业课程,对学生的专业素养和实践能力有着重要的影响。而ARCS动机模型作为一种有效的教学理论模型,可以帮助教师更好地激发学生的学习动机和学习兴趣。因而研究基于ARCS动机模型的高校机械制图课程教学实践有重要的意义。对此,通过阐述ARCS动机模型的理论框架,分析基于ARCS动机模型的高校机械制图课程教学实践策略,以期为高校机械制图课程的教学改进提供一定的参考和借鉴。

基于ARCS的蒙古族学龄前儿童教育APP界面视觉设计

目的通过ARCS动机模型的4个要素,构建出蒙古族学龄前儿童汉语学习APP的界面视觉设计模式,并使用此模式进行设计实践。方法首先,运用文献研究法提取出ARCS动机模型的4个要素,确定基于ARCS动机模型下蒙古族学龄前儿童对学习动机各指标的需求权重;其次,通过正交表确定APP界面视觉设计的组合模式,建立界面设计视觉稿样本,收集受试者的相关实验数据;再次,基于联合分析法构建学习动机与界面视觉设计模式之间的关系模型;最后,根据此结果确定最佳设计方案,使用Likert5点量表对此设计方案进行结果验证。结果基于ARCS动机模型下的界面视觉设计模式组合可构建为视觉形式的生态化、图标样式的拟物化、字体样式的娃娃体、字体大小的50 px、色彩识别的#ffffff/#ffe6a2/#b7eb6d/#00bae5。结论基于ARCS动机模型下蒙古族学龄前儿童汉语学习界面的视觉设计模式,可以有效获取蒙古族学龄前儿童汉语学习各指标的动机偏好,证明了该模式可以有效维持和激发蒙古族学龄前儿童汉语教育的学习动机,成为了一种可行性的设计方案。

Three-Dimensional Modelling of a DC Arc in Cross-Flow

A commercial CFD （computational fluid dynamics） code FLUENT was used and modified to model an atmospheric pressure argon arc in a low cross flow by solving the fully coupled conservation equations. Numerical experiments, with an arc current of 100 A to 200 A, an arcing distance of 3 mm to 6 mm, and a cross-flow velocity of 10 m/s to 30 m/s, were carried out. The modelling results show that the arc tends to take the shortest path to the anode when deflected by the cross flow; its anode attachment is farther downstream than the cathode one. Furthermore, due to the low input gas flow imposed in this study, the effect of electromagnetic force is important and it influences the crosscut shape of the arc significantly.

基于ARCS模型的产教研融合模式的课程改革与实践——以“薄膜光学与技术”课程为例

针对当前薄膜光学与技术课程教学中存在的学生学习积极性不高、实践能力培养不充分、人才培养与社会需求关联不紧密等问题,结合专业特色和人才培养目标,基于新时代发展对创新人才的需求,提出基于ARCS动机模型的产教研融合模式对课程进行改革与实践,充分调动学生学习主动性,提高学生的实践能力和创新能力。探索基于ARCS模型的产教研融合的教学模式在薄膜光学与技术课程中的应用,优化知识体系,重构教学设计,将教学内容和课程思政深度融合,致力于培养具有创新意识和解决复杂问题能力的高质量人才。

基于ARCS模型的游戏教学法在实验课程中的实践

以注意力(attention)、切身性(relevance)、自信心(confidence)、满意感(satisfaction)四要素为驱动的ARCS学习动机模型是一种激发学生学习动机的教学设计模型。本文介绍在课程“结构模型概念与实验”中基于ARCS模型,在课堂中引入游戏教学法的改革实践。以实践类游戏为例展示了如何基于ARCS学习动机模型进行教学游戏设计,并介绍了课程中所采用的“米粉-棉花糖结构游戏”、“结构仿真平台严肃游戏”、“结构知识、一站到底”游戏、“静动载模型实验竞赛”等案例的实施情况。调查问卷等反馈结果表明:根据课程的特点,精心设计教学游戏并有机融入到课程中去,可提高课堂活力,激励学生主动学习,达到良好的教学效果。文章对其他相似的实验课程具有借鉴意义。

基于ARCS模型的信息技术课程合作学习设计

信息技术教学中采用合作学习会改变课堂中师生的角色定位。在合作学习中,学生在教师的帮助下以小组为单位进行合作探究,完成学习任务,但实施时往往由于缺乏有效的设计策略而流于形式。凯勒教授构建出ARCS模型,主张从注意、关联、信心和满意四个方面激发与维持学习动机。将ARCS动机模型应用于信息技术课程合作学习,在各教学环节设计相应的动机策略,基于实际教学案例阐明设计方法和应用流程并进行教学实践,结果表明,进行合作学习设计时合理应用ARCS动机模型能提升学生的动机水平,实现有效合作学习。

Arcing Model of a Disconnector and its Effect on VFTO

In the computational process of very fast transient over-voltage （VFTO）, it is essen-tial to find an accurate model for a gas insulated substation. The arcing model of the disconnector is particularly important. The general arcing model is not able to give a good description of the arc development process. In this paper, based on the physical process of arcing and existing arc models （the exponential time-varying resistance model and the segmental arcing models）, a dy- namic arcing model is proposed, which is divided into two stages before and after the zero crossing. The dynamic arcing model combines hyperbola time-varying resistance and the Mayr model to describe the dynamic process of arcing. The present paper creates an arc model blockset upon the Matlab/Simulink software platform. Moreover for a specific 1100 kV station, VFTO is simulated in detail based on different arcing models. It is demonstrated that the dynamic arcing model can describe the physical arc process precisely and is useful for improving the accuracy of VFTO simulations.

基于ARCS模型+线上线下混合的“数据结构”课程教学模式研究

为促进新工科建设,落实教学改革“最后一公里”,文章对数据结构课程进行教学内容、方法和考核全方位的改革与实践探究,采用OBE教学理念,结合ARCS动机激励模型对学生持续激励,学生获得自我认可和学习动力,三阶段的线上线下混合教学模式,学习延展至课堂外,构建以学生为中心的教学过程。将行业发展和课程相关新知识、技术融入教学内容,适当提高课程挑战度,以能力培养为主线,增强产业融合,促进学生对理论知识的理解和实际运用,达到培养符合社会需求、能解决计算机类复杂工程问题创新人才的教学目标。

Modeling of electrode system for three-phase electric arc furnace

To simulate the process of electrode operation, a dynamic model describing the electrode system of three-phase electric arc furnace was developed. This new model can be divided into three submodels in terms of the practical situation. They are the power supply system model the electric arc model and the hydraulic actuator system model. According to the basic circuit theory, the power supply system model where the high voltage transmission circuit and mutual inductances were considered, was set up. The electric arc model, which was novel for the electrode control, served as the electrical load and was connected to the power supply system model. The hydraulic actuator system model consists of the proportional valve part that is modeled to capture the dead-zone nonlinear characteristics and the hydraulic cylinder part where the impact of the load force is taken into account. By comparing simulation data and actual data, the results show that the electrode system model is proved to be accurate.

Modeling the keyhole shape and dimension in plasma arc welding

It is of great significance to model the keyhole shape and dimensions to optimize the plasma arc welding process parameters. In this study, through employing a combined volumetric heat source mode, the weld pool in keyhole plasma arc welding is determined firstly, and then the dynamic force-balance condition on the interface between the plasma jet and the molten metal is dealt with in describing the keyhole formation inside the weld pool. The effects of welding current on the shape and size of keyhole are numerically analyzed. The sharp transformation from a partial keyhole to a full-penetration keyhole is quantitatively demonstrated.