电子电工技术在电力系统的应用

电子电工技术是一门计算机的分支学科,也就是人们常说的跨学科的学科。电子电工技术是电力领域中一项新兴的技术,本文主要介绍电子电工技术在电力系统中的应用,主要集中在发电环节,输电环节,配电环节和节能环节方面的用途。电子电工技术是一门综合的学科,它包括计算机技术、电子技术、电力技术和控制技术。如何才能把电力电子技术的作用发挥到电力系统中来,是现在很多科学家和技术人员所探求的问题。

Key techniques of symmetrical machining

To improve the machining efficiency of large symmetrical freeform surface, this paper proposes a new machining method： symmetrical machining （SM）. Based on the concept of collision avoidance plane （CAP）, collisions among cutters or headstocks are avoided, and the area of machining residue is controlled effectively. Machining residue is eliminated due to proper design of symmetrical tool in mechanism and control project. Taking 5-axis symmetrical machine with columnar headstocks and flat cutters as example, this paper proposes collision avoidance algorithm. Finally, using a twin-skeg ship model surface as an example, the method is applied to avoiding collisions in original tool path. Simulation and real machining results show that the scheme is practical. Furthermore, the machining efficiency of SM is improved 85% more than that of the traditional single cutter technology.

An Investigation on Telecommunication Staff＇s Acceptance of E-Learning Technology

As the information on telecommunication products updates rapidly, using E-learning in staff training becomes an edge for company operation. However, previous studies showed that staff＇s attitude toward E-learning significantly affected the outcomes of training. The purpose of this study is to investigate the acceptance of E-learning in a telecommunication company. The researchers adopted the technology acceptance model （TAM） and diffusion of innovation theory to evaluate the perceived usefulness and perceived ease of use on E-learning, in addition to employees＇ self-directed learning motivation, attitude toward computers, and organizational influence. We randomly chose 571 employees of the telecommunication entrepreneur at the Taichung office in Taiwan to participate in this survey. The result showed that employees＇ background factors such as age, job position, marital status, education level and the scale of job unit had the significant impact on behavioral intention to use E-learning. Employees＇ self-directed learning, attitude toward computers, and organizational influence respectively also had positive effects on perceived usefulness of E-learning and perceived ease of use of E-learning. Furthermore, employees＇ perceived usefulness of E-learning and perceived ease of use of E-learning also had a positive effect on behavioral intention to use E-learning systems.

One-pot synthesis of Li_3VO_4@C nanofibers by electrospinning with enhanced electrochemical performance for lithium-ion batteries

Electrospinning is firstly used to one-pot synthesis of Li3VO4@C nanofibers in a large scale. Although with the presence of organic sources in synthesis process, the pure phase Li3VO4 with superior nanofibrous morphology is still successfully obtained through adjusting different heat treatment processes and different vanadium sources. The prepared Li3VO4@C nanofibers exhibit a unique structure in which nanosized Li3VO4 particles are uniformly embedded in amorphous carbon matrix. Compared with LiBVO4/C powder, Li3VO4@C nanofibers display enhanced reversible capacity of 451 mAhg^-1 at 40mAg^-1 with an increased initial coulombic efficiency of 82.3%, and the capacity can remain at 394 mAh g ^-1 after 100 cycles. This superior electrochemical performance can be attributed to its unique structure which ensures a high reactivity by nanosized Li3VO4, more stable electrode/electrolyte interface by carbon encapsulation, improved electronic conductivity and buffered volume changes by flexible carbon matrix. The electrospinning technology provides an effective method to obtain high performance Li3VO4 as a promising anode material for lithium-ion batteries.