工频炉高压起动柜控制系统研究

工频炉现在使用越来越广泛,但起动异常和烧高压起动柜中电抗器等现象一直是困扰生产的首要问题。通过对某机修厂铸铁车间工频炉起动异常和烧高压起动柜中起动电抗器情况的分析,制定了高压起动柜控制系统的改进方案,通过增设保护电路和报警电路等装置,提高了设备运行的稳定性。     

Fibonacci序列{F_(kn r)}模F_n~2的同余式

利用Fibonacci序列的定义及基本性质得到了Fibonacci序列{F_(kn)}模F_n~2的同余式和序列{F_(kn r)}的递归关系,然后归纳得出了{F_(kn r)}模F_n~2的同余式的一般情况,并证明了其正确性.     

Facilitators or suppressors: Effects of experimentally induced emotions on multimedia learning

The present study investigated the influence of experimentally induced emotions (positive, neutral, negative) on learning with multimedia instruction with N = 75 university students. In order to provide sound explanations about how emotional state might impact learning, measures of motivation, cognitive load, and attentional processes (eye tracking) were integrated. Results showed that while emotions did not influence retention, emotions did influence outcomes of the comprehension and transfer test. Specifically, a facilitating effect of an induced negative emotional state on learning outcomes was observed, which could be attributed to a more focused and detailed information processing. In contrast, an induced positive emotional state had a suppressing effect on learning outcomes since learners were distracted from the learning materials by their emotions. Motivational measures were not influenced by learners' different emotional states, but overall, controlled motivation increased and autonomous motivation decreased during learning. In sum, the learners' emotional state should be considered in learning research as an important predictor for learning success.     

The Perceptions of Success Inventory for Beginning Teachers: Measuring its psychometric properties

This study investigated the construction and evaluation of an instrument called the Perceptions of Success Inventory for Beginning Teachers (PSI-BT) intended to measure factors documented in research that contribute to beginning teachers’ perceptions of success. The PSI-BT was found to assess the following factors using exploratory factor analysis: (1) Administrative Support, (2) Classroom Climate, (3) Mentor Support, (4) Colleague and Instructional Resource Support, (5) Commitment, and (6) Assignment and Workload. Internal reliability, content validity, and concurrent validity were also measured in the validation process. Our findings suggest that the PSI-BT provides a reliable and valid instrument that can provide schools with valuable feedback to ensure the success of their beginning teachers.     

异步电动机重合闸综合实验研究

研究异步电动机重合闸过程,提出解决合闸过程中冲击电流过大的方法,以此为模本设计异步电动机重合闸实验,开发工程技术性的新类型电机实验。该实验的实现过程从实际的电机工程应用技术出发,按工程需要模块化地揉合相关课程,充分调动学生的创新性综合思维能力,有益于培养基础扎实、创新意识强、动手能力高的应用型优秀电气工程技术人才。     

On-line broken-bar fault diagnosis system of induction motor

Induction motor faults including mechanical and electrical faults are reviewed. The fault diagnosis methods are summarized. To analyze the influence of stator current, torque, speed and rotor current on faulted bars, a time-stepping transient finite element (FE) model of induction motor with bars faulted is created in this paper. With wavelet package analysis method and FFT method, the simulation result of finite element is analyzed. Based on the simulation analysis, the on-line fault diagnosis system of induction motor with bars faulted is developed. With the speed of broken bars motor changed from 1 478 r/min to 1 445 r/min, the FFT power spectra and the wavelet package decoupling factors are given. The comparison result shows that the on-line diagnosis system can detect broken-bar fault efficiently.     

论彝族天神

天神崇拜是古代民族和现代后进民族的普遍信仰行为。由于地理环境、历史和文化背景不同,各个民族天神崇拜的对象、内涵、职能及其发展演变的方式是不一样的。先秦时期,汉族前身——中原华夏族就十分崇敬天神,乃至后来长达两千多年的封建社会,历朝历代的皇帝都要亲登泰山祭天。汉藏语系藏缅语族彝语支白、纳西、彝、傈僳、景颇、基诺各族普遍崇拜天神,祭仪隆重,直到今天仍保留。彝族的天神崇拜经历了自然崇拜到祖先崇拜、人格神崇拜的发展演变过程,并产生了“天人感应”、“天人合一”的哲学理念。     

大麦胚性愈伤组织细胞ODO冷冻断裂面的扫描电镜观察

ODO冷冻断裂法是一项扫描电镜生物样品制备的有效技术,它在生物医学的形态学研究中发挥了重要作用,把这个技术用到植物离体培养物的超微形态研究,是一个新的尝试.大麦胚性愈伤组织用低浓度的戊二醛前固定,再用ODO冷冻断裂法制备扫描电镜样品.本研究主要观察了淀粉粒和淀粉质体在胚性愈伤组织细胞中的分布,因为淀粉粒沉积的变化和质体结构的变化是去分化和再分化过程中的重要特征之一.本文还图示了自制的冷冻断裂器,并对ODO冷冻断裂法的应用作了一些讨论.     

驱蚊香草不同外植体诱导愈伤组织的研究

先后用驱蚊香草的叶片、叶柄、幼嫩顶芽、休眠芽、带皮茎段、去皮茎段等作外植体,进行愈伤组织的诱导.结果表明:在所有的外植体中,以幼嫩顶芽为最好,去皮茎段、叶片次之,愈伤组织诱导率分别为94%、89%和80%;带皮茎段和叶柄的愈伤组织诱导率较低,为25.7%和14.3%左右,休眠芽未诱导出愈伤组织.     

对电磁感应本质的探索

在电磁感应现象中，动生电动势是由电荷受到洛仑兹力的作用而产生的；从能量的观点看，电源的能量是由洛仑兹力对电荷作功转化而来的．