一种新型永磁同步电机用无位置传感器控制算法

目前在永磁电机控制领域中，使用无位置传感器的电机调速方式获得了广泛的应用与发展。通过过去几十年的不懈研究，出现了多种无位置感应器控制算法，通常这些算法可以被归为两类，即仅适合于电机高速区使用的算法以及仅适合于电机低速区使用的算法，但是到目前为止，没有任何一种算法能够在电机的整个调速范围内都有效。本文提出了一种新型的融合了高速算法和低速算法优点的混合算法，该算法在电机的整个调速范围内都能有效的估算转子位置。     

以学生为主的控制电机课程教学方法

针对控制电机课程综合性强、内容复杂、理论抽象、学生难懂的问题,开展了基于以学生为主的课堂和实验相结合的教学方法研究。在以学生为主的课堂教学方面采用以学生为主、教师为辅的教学形式,结合北航工科的特点,在强调基础理论教学的同时,突出各种控制电机在实际工程中的作用,增强学生对各种控制电机基本原理的理解;在实验教学方面,设计了基本类-综合类-创新类三个层次的课程实验,培养学生的动手能力、应用能力和创新能力。经研究和教学实践表明,基于以学生为主的课堂和实验相结合的教学方法可以有效地调动学生的学习积极性,增加学生对课程内容的理解,提高学生分析问题和解决问题的能力,取得了较好的教学效果。     

浅议现代工厂企业的节电技术

本文简叙了当前工矿企业供用电的状况，讨论了开展节电工作的途径，重点分析了电气设备无功电耗的原因，汇集了部分节约电力的新观念、新技术、新措施。     

Worker deployment in dual resource constrained systems with a task-type factor

This paper investigates worker learning and forgetting phenomenon in a dual resource constrained system (DRC) setting. Worker learning and forgetting in two and three stage DRC systems are modeled according to the dual-phase learning and forgetting model (DPLFM), which is based on the theory that a task has separate cognitive and motor requirements. Results show that the task-type (with respect to its learning rate and proportion of cognitive and motor requirements) affects the performance of training and deployment policies in DRC systems, and as such it should be included in future DRC research.     

一种新型永磁同步电动机的直接转矩控制方法

基于永磁同步电动机的转矩和磁链方程，介绍了一种改进的直接转矩控制方法。在该控制方法中，引入了一种新的电压空间矢量调制技术，这种调制技术的特点是把电动机的转速作为开关表的一个输入量，实现了定子电压空间矢量的精确选择，有效的降低了转矩、定子磁链和定子电流的波动。仿真实验结果验证了这种控制方法的有效性。     

Effects of adenosine triphosphate concentration on motor force regulation during skeletal muscle contraction

We employ a mechanical model of sarcomere to quantitatively investigate how adenosine triphosphate (ATP) concentration affects motor force regulation during skeletal muscle contraction. Our simulation indicates that there can be negative cross-bridges resisting contraction within the sar-comere and higher ATP concentration would decrease the resistance force from negative cross-bridges by promoting their timely detachment. It is revealed that the motor force is well regulated only when ATP concentration is above a certain level. These predictions may provide insights into the role of ATP in regulating coordination among multiple motors.     

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针对链式维护机械臂(EAMA)运行环境的特殊性,对其伺服控制系统进行设计和实现.在控制结构上,系统在基于分布式控制结构的基础上采用了一种新的伺服系统解决方案.在控制策略上选用了高性能PIC单片机进行了硬件电路的设计,并采用了位置、速度双闭环控制算法以实现对机械臂的每个关节的高精度位置伺服控制.通过实验验证了该系统能够满足机械臂的运行要求,且具有良好的动态性能和稳态性能.     

EAST链式维护机械臂伺服控制系统设计

针对链式维护机械臂(EAMA)运行环境的特殊性,对其伺服控制系统进行设计和实现。在控制结构上,系统在基于分布式控制结构的基础上采用了一种新的伺服系统解决方案。在控制策略上选用了高性能PIC单片机进行了硬件电路的设计,并采用了位置、速度双闭环控制算法以实现对机械臂的每个关节的高精度位置伺服控制。通过实验验证了该系统能够满足机械臂的运行要求,且具有良好的动态性能和稳态性能。     

Variations in adductor spasmodic dysphonia:Acoustic evidence

Acoustic analysis was used to gain information about the normal, aswell as the abnormal acoustic events associated with adductor spasmodic dysphonia (ADSD). This analysis was completed to determine whether specific acoustic events could be used to differentiate the voice of individuals with ADSD from those with normal voice. A group comparison between 14 women diagnosed with ADSD and 14 women (age-matched) with no evidence of vocal pathology or vocal dysfunction was completed. Phonatory breaks, aperiodicity, and frequency shifts, acoustic parameters previously identified in ADSD, were found throughout sustained vowel productions. The duration of the phonatory breaks and aperiodic segments was calculated and the amount of frequency shift was determined. The location of each acoustic event was marked relative to the onset of the vowel production. The subjects with ADSD presented with normal phonation and various amounts of each of the three acoustic parameters. Aperiodic segments primarily characterized the phonation of ADSD, followed by frequency shifts and phonatory breaks. The location of each of these acoustic events was within the midportion of the vowel production. The advantages of segmenting the acoustic waveform into these measures and separating the spasmodic events from normal phonation when examining laryngeal motor control of spasmodic dysphonics is discussed