机械专业开设信号与系统课程教学研究与探讨

学科间交叉是现代社会人才需求方向。针对机械类学生开设信号与系统课程,是为了培养从事机械设备状态、机器故障诊断技术、振动信号检测等领域的专门人才。分析传统教学中存在的问题,针对机械专业学生从教学改革思想、调整教学内容,优化教学手段、创新教学方法4个方面进行了教学改革与实践。     

贵阳市十字路口交通信号灯的PLC控制方法研究

依据PLC具有可靠性高,抗干扰能力强和适应面广的特点,利用它可以组成能满足各种控制要求的控制系统,将其放入交通信号灯控制系统中进行研究,结论是这项设计的内容在应对繁重的十字路口交通信号灯控制工作和工作的可靠性方面是完全可行的。     

Developing Self-Regulated Learners: Goal Setting,Self-Evaluation,and Organizational Signals During Acquisition of Procedural Skills

The authors examined how 2 types of goal setting (process vs. outcome), self-evaluation (presence vs. absence), and organizational signals (presence vs. absence) affected student ability to perform a set of procedural skills, namely animating slides created via presentation software. They also examined how these variables influenced a variety of affective outcomes, including students' self-efficacy, satisfaction with their performance, evaluation of the instruction, and attributions of success or lack of success in acquiring the skills. Using a 2 X 2 X 2 (Goal Setting X Self-Evaluation X Organizational Signals) design, 96 ninth- and tenth-grade students were randomly assigned to 1 of 8 versions of a print-based instructional module designed to teach slide-animation skills. Results indicated that students in the process goal condition reported a higher degree of self-efficacy, more satisfaction with their performance, and more strategic attributions than students in the outcome goal condition. Moreover, among students who were not directed to self-evaluate their own work, those students in the process goal condition demonstrated a higher level of animation skills, self-efficacy, and satisfaction, and rated the instruction more positively than did their counterparts in the outcome goal group. Self-evaluation also had a positive effect on student skill acquisition, particularly for students in the outcome goal condition. Organizational signals did not have any effect on any of the dependent measures. These results are discussed from a social cognitive perspective of self-regulation.     

高等教育文凭信号的经济学解析

由于劳动力市场信息不对称,招聘大学生是一种风险投资决策.大学毕业生择业与考研受到来自市场工资与预期收益率的影响.高等教育文凭信号仅发挥着筛选与甄别作用,是社会所需要设置的、不完备衡量大学生工作能力的"过滤分拣器".人力资本理论在教育收益率方面已呈现出危机.笔者认为,优质高等教育文凭信号是解救当前教育体制的无效率,促进高等教育可持续发展的引擎.     

基于小波分析的配电网故障选线方法研究

提出了一种基于小波分析的配电网故障选线方法。通过剔除线路谐振状态的频带,利用小波包良好的分频特性,以适当带宽对故障后线路的暂态零序电流进行分解,从而实现在低频段下对各线路的零序电流进行小波重构,通过比较重构后的信号来实现选线。仿真实验表明,该选线方法受故障点位置、故障时刻、过渡电阻等因素影响较小,具有可靠性高、抗干扰能力强的特点,适用于中性点不接地的配电网。     

宁波市民工子弟学校现状分析与发展对策

解决流动人口子女的教育问题,保障处于社会弱势地位的民工子女的教育权,是城市化进程中出现的一个新课题。通过对宁波市民工子弟学校现状的调查分析,提出了规范发展的若干对策。     

Wavelet-based deconvolution of ultrasonic signals in nondestructive evaluation

INTRODUCTION Deconvolution of ultrasonic signals is defined as the solution of the inverse problem of convolving an input signal, known as the system function h(n), with a medium reflectivity function x(n) and can be rep- resented by y(n)=h(n)*x(n) η(n), (1) where y(n) is the measured signal, * denotes the convolution operation and η(n) is the additive noise. Recovering x(n) from the observation y(n) leads to improving the appearance and the axial resolution of the RF-signals by removin…     

ANSYS在结构动力分析中的应用

结合使用经验，总结了基于通用有限元软件ANSYS进行瞬态动力分析、模态分析、谱分析等动力分析的有关问题及解决方法，可供使用ANSYS的工程技术人员参考。     

实验编导课中不同录像带的视频编辑技巧

重点介绍了处理不同格式录像带时，视频编辑的技巧。     

The Oracle in Ode on a Grecian Urn of Keats

In the Ode to the Grecian Urn Keats came to the realization that the immortality he had quested for is a myth that cannot be interpreted. The marbleized sacrificial rite on the ancient urn implies that human life is a process of endless sacrifice. This inevitable recognition of mortal limitation during the process of human growth can not be dissolved by the soothing oracle that ＇Beauty is truth, truth beauty＇.