This paper presents the development of an initial rotor position estimation of permanent magnet synchronous motors (PMSM) without a position sensors drives with embedded digital signal controller. The principle of the estimation is based on induced voltage of electromagnetic flux by injecting high-frequency voltage at standstill. The controller is embedded digital signal controller (DSC) due to the small and cheap controller. Experimental results show that changing initial frequency capable of reliable.

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Thermoelectric properties of cubic perovskite SrTiO3 have been investigated. The energy band structures are calculated using the total energy plane-wave pseudopotential method within the local density approximation (LDA) and generalized gradient approximation (GGA). The calculated energy band structures are then used in combination with Boltzmann transport equation to calculate the thermoelectric parameters of doped SrTiO3 especially seebeck coefficient electrical conductivity and electronic thermal conductivity.

This research is Design and construction board led dot matrix was create for study about microcontroller. It apply to use in communication & information indoor type by sending messages from computer on internet network systems. This research has implemented LED dot matrix display for display message characters. The research is composed of 4 major parts: the first part is LED dot matrix display with dimension of 16x192 dots. The second part is the control circuit by using a micro-controller ARM 7 which receives the data from computer the third part by using Microsoft Visual Basic. the forth pat program remote desktop. From tests and results we have found that it can display the message characters which move from Internet System successful.

The purposes of the research were to create computer assisted instruction for Electric Power System Analysis Chapter 1-2 to find out the efficiency validation of computer assisted instruction based on the standard of 90/90 and to analyse the students learning achievement after using the computer assisted instruction. The subjects in the study were 17 third-year diploma engineering students enrolling at Rajamangala University of Technology Phra Nakhon. The researcher made the experiment by having the students pretest. Then they studied by using the computer assisted instruction focused on practicing basic turning. After the students had studied and had posttest the efficiency of the computer assisted instruction was calculated as well as the learning achievement was analysed. The research result revealed that the efficiency of the computer assisted instruction was at the standard of 90 / 90. Moreover the learning achievement after using the computer assisted instruction was different at the significant level of 0.05.