Effect of drive control on dynamic characteristics of spacecraft tracking-drive flexible systems

At the current stage of the development of means for automatic control for the formation of qualitative systems of machines, construction and road machinery, railway transport there are used electro-hydraulic devices transforming electric input signals into hydraulic output power. To carry out a generalized analysis and for the fulfillment of the preliminary synthesis of an automated hydraulic system on the whole the static and dynamic characteristics of its separate units should be obtained. In the paper there is presented a calculation of a theoretical dynamic characteristic of the electro-hydraulic nozzle-flap converter to substantiate potentialities of its inclusion as an adjusting device acting upon rods of a high-pressure fuel pump in the system of fuel feeding control of a KamAZ motor-car engine. At that the converter was considered as interconnected units: a unit of feedback. The methods of the investigation of processes in the converter are based on the fundamentals of the theory of automatic control. As it follows from the transition function diagram obtained as a result of the investigations carried out the transition time of a electro-hydraulic converter slide valve movement from a neutral position into an extreme one in the course of sending a maximum control signal to the coil does not exceed 1.1 sec, that is satisfactory for the formation of hydraulic drive control systems.

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Practical Resources for Provision of Services to Culturally and Linguistically Diverse Users of AAC

Perspectives on Communication Disorders and Sciences in Culturally and Linguistically Diverse Populations ◽

10.1044/cds22.1.25 ◽

2015 ◽

Vol 22 (1) ◽

pp. 25-39

Author(s):

Elena Dukhovny ◽

E. Betsy Kelly

Keyword(s):

Best Practices ◽

Augmentative And Alternative Communication ◽

Linguistically Diverse ◽

Intervention Strategies ◽

Culturally And Linguistically Diverse ◽

Limited Resources ◽

Flexible Systems ◽

Alternative Communication ◽

Practical Applications ◽

Provision Of Services

According to the 2010 U.S. Census, over 20% of Americans speak a language other than English in the home, with Spanish, Chinese, and French being the languages most commonly spoken, aside from English. However, few augmentative and alternative communication (AAC) systems offer multilingual support for individuals with limited functional speech. There has been much discussion in the AAC community about best practices in AAC system design and intervention strategies, but limited resources exist to help us provide robust, flexible systems for users who speak languages other than English. We must provide services that take into consideration the unique needs of culturally and linguistically diverse users of AAC and help them reach their full communication potential. This article outlines basic guidelines for best practices in AAC design and selection, and presents practical applications of these best practices to multilingual/multicultural clients.

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