The trend of energy savings has been widely interested and phase shift transformers (HMT) have been extensively used. This paper presents the investigation of the effect of harmonic currents on losses of the HMT. In this paper a 15-degree HMT with quad secondary winding is applied to find the relationship between harmonic currents and losses of the HMT. This relation can be met by testing the active power of primary and secondary sides while the HMT supplies for two and four non-linear loads at 25% 50% 75% and 100% rated currents respectively. The results reveal that harmonic currents affect winding eddy current losses significantly and the losses for loading the two secondaries 1 and 2 are the same as loading the two secondaries 1 and 3 while both %THDi are different. However for loading the secondaries 1 and 2 the %THDi is more than 15% so it is not met IEEE 519 Std. while the HMT is supplied with four loads the %THDi has met IEEE 519 Std. and the losses are less than 57% compared to one load. As a result of these if the HMT is applied to an adjustable speed drive system it is not only reduced the harmonics but also saved the energies.

This research is a survey research. The purpose was to study the realization of environmental ethics of Rajamangala University of Technology Phra Nakhon students towards the refuse disposal problem and analyzing the factor that influence their realization of environmental ethics. The subject for this research was randomly selected form the undergraduate student of Rajamangala University of Technology Phra Nakhon in the academic year 2007 by using the simple random sampling technique. The instruments used in this research were questionnaires. The data was analyzed by percentage mean standard deviation and Hest. The research found out that the students had a high level of the realization of environmental ethics about 49.47 percent. About 30.37 percent had a medium level and about 19.30 percent had a low level. Gender did not difference in realization with statistical significance at.05. The factor that influence their realization of a high level environmental ethics were age about 18 -20 year old occupation of parent was governors a monthly income of 5001 -8000 baht the education level finished undergraduate. The respondents were received environmental information. Habitat and gender did not make the difference in their realization.

This survey research aimed to study the realization of environmental ethics of Rajamangala University of Technology Phra Nakhon students towards the refuse disposal problem and to analyze the factors that influence their realization of environmental ethics. The subject for this research was randomly selected from the undergraduate students. The instruments used in this research were questionnaires. The data were analyzed by percentage mean standard deviation and t-test. The research was found that 49.47 percent of the students had a high level of the realization of environmental ethics 30.37 percent had a medium level and 19.30 percent had a low level. Gender is not different.