This thesis proposes technical performance evaluation and economic decence for the combination of harmonic correction devices in Industry. Currently an electronic device is popularly applied in power network. Although it is a higher performance device than the existing device it still causes the power quality issues and then network failure. Especially harmonic disturbance in the network it is a harmonic source that generates harmonic current into the network. Many types and solutions are available in the present time therefore the suitable and optimal financial solution must be considered. A network model for the analysis of harmonic correction devices suitable solutions and optimal financial has been established in the simulation software that bases on the power and Break Even Point (BEP) equations. The results of analysis shown that the performance of harmonic correction devices suitable solution and BEP of investment in match to the using of a detuned filter bank and an active harmonic filter (case 8) thus these information will be valued for the end-user.

The purposes of this research were (1) to study and (2) to rank the needs of RMUTP environment management on undergraduate students’ learning development as well as (3) to present a proposed guideline to improve RMUTP environment. 343 students enrolling in the first semester of the academic year 2015 were selected with simple random sampling. The research tool was questionnaire. The data were analyzed through percentage (%) mean ( ) standard deviation (S.D) t-test modified priority needs index: PNI modified and content analysis. The results demonstrated that: (1) The overall mean scores of the reality and expectation of RMUTP environment on students’ learning are statistically different at 0.01. (2) The physical environment needs for supporting students’ quality of life was ranked the first. The second was university facilities to enhance their learning and the third was help and information service. The curriculum management was ranked the fourth. The last one was instructors. (3) A students’ proposed guideline: 3.1 As for physical environment needs for supporting students’ quality of life the highest was more relaxing space. 3.2 As for university facilities to enhance their learning the highest was that learning equipments should be adequate for them. 3.3 As for help and information service public relation and university information for students should be improved at a high level. 3.4 As for curriculum management the study suggested students’ needs for curriculum development to meet current employment demand and to implement effectively at the workplaces. 3.5 As for instructors the highest rank was that instructors ought to understand and listen to students’ needs. They should let students express their opinions.

This thesis presents an assessment of voltage sags when faults are happened in the 115 kV transmission line of the Provincial Electricity Authority (PEA) when distributed generation (DG) is installed in the system. The computer program PSCAD/EMTDC (Power Systems Computer Aided Design / Electromagnetic Transient in DC system) version 4.2 is applied to provide electrical parameters for the modeling and simulation and to analyze the fault occurred which resulted in voltage sag. Test results from PSCAD/EMTDC show the values of voltage sag when 5 types of fault are occurred (Single Line to Ground Fault Double Line to Ground Fault Three Phase to Ground Fault Line to Fault and Three Phase Fault). For all cases the value of root mean square voltage before fault is 100% or 1.0 pu. It can be seen that for both radial line and closed circuit when DG are installed in the system the value of phase to ground RMS residual voltage and phase to phase RMS residual voltage at the bus of Bang-pa-in 2 substation are more than the values in case of the system without DG.

The aim of this research was to study the solid waste management in Faculty of Science and Technology Rajamangala University of Technology Phra Nakhon study problems and obstacles of the solid waste management. The study will benefit related organizations as fundamental information for setting plans on the solid waste management to ensure the maximum efficiency and expand to other faculties. In this study a researcher collected quantitative data and also characteristics of solid waste occurred. Total amounts of solid waste were approximately 20.86 kilograms per day. Types of solid waste mostly found were reuse /recycle wastes (10.21 kilograms per day) and organic wastes (10.43 kilograms per day). The results showed an information for developing solid waste management under 3R processes (Reduce Reuse and Recycle) lead to sustainable solid waste management and efficiency.

For this work PM10 were collected from 7 stations within the area of North Phra Nakhon campus Rajamangala University of Technology Phra Nakhon Thailand. The samples were collected within 24 hours from January to April 2015. The result shows that the concentrations of PM10 values are in the range of 0.06 - 0.16 mg/m3 and average PM10 of 0.09 mg/m3. The maximum PM10 were found in front of the university. The comparison of maximum PM10 with the standard value of Pollution Control Department (PCD) was slightly over but did not affect human health.