Performance estimation method for in-service single-phase induction motors
This paper proposes a performance estimation method for single-phase induction motors in the field at any operating load using a set of data from in-service measurement. This paper describes the use of the improved equivalent circuit models based on double-revolving-field theory which a core loss element is properly added in order to provide more accurate results. The appropriate values for the model parameters can be evaluated by the use of measured data coupled with the genetic algorithms. The estimated performance result of several motors are presented and then compared to the measured values obtained from load tests, and clearly illustrate that agreement between the proposed method and the actual one is good.
An economical method for induction motor field efficiency estimation for use in on-site energy audit and management
This paper proposes an economical method that can help the plants to make right decision in replacing the inefficient induction motors with more efficient ones. This method focuses on the field efficiency of motors without the needs for removing motors and measuring the output power. The use of a few sets of measured data from field test coupled with the genetic algorithms for evaluating motor equivalent circuit instead of using the no-load and blocked-rotor tests is proposed. To illustrate how well the estimated efficiency matches that of calculated obtained from the standard evaluations, the results of various induction motors rating up to 100 hp are presented. Test results indicate that this method has a high accuracy, then it is suitable for conducting on-site energy audits of motors in order to project cost savings and payback and to support a confidence decision regarding the investment in higher efficiency motors.
Determinant factors of entrepreneurship intentions of electronic technology education students in Nigerian universities
The major purpose of this study was to explore the determinant factors of entrepreneurship intentions of Electronic Technology Education students in Nigerian universities. The study explored the influence of entrepreneurial factors as well as entrepreneurial learning experiences activities on the entrepreneurial intentions of Electronic Technology Education students in the universities. The study adopted a correlational survey research design. The population for the study was 366 Electronic Technology Education undergraduate students. There was no sampling as a result of the manageable size of the population. The students were surveyed by direct contact using questionnaire. They were asked to indicate the entrepreneurship learning experiences activities they were participating in/would participate in as part of their curriculum. Data collected were analysed using descriptive statistics and multiple regressions. The findings show that the more entrepreneurial activities students are engaged in, the less the influence of entrepreneurial factors on their entrepreneurial intentions and this significantly increased entrepreneurial intentions of students who prefer career choice as an entrepreneur. The findings also revealed that there is a positive relationship between gender, age, career choice, parents’ occupation, and entrepreneurial intentions of Electronic Technology Education undergraduate students. It was recommended that Electronic Technology Education undergraduate students should see career options with a balance view in order to understand their abilities before deciding to venture in any electronic business enterprise.