The purposes of the research were to create and efficiency validation of computer Assisted for the courses of practiced to reading Creating and Evaluating the Effectiveness of Computer Assisted Instruction Program Subject Manufacturing Processes Chapter 5-8. based standard 90/90 and analyses the leaning achievement of the student after by using computer assisted instruction . The subjects in the study were 25 first year. Diploma students enrolled in Rajamangala University of Technology Phra Nakhon. The Researcher using the experiment by let the students do until test before class And then study by using computer assisted instruction focused on practiced to basic turning . After that let students do the unit test again at the class and calculate to find out the efficiency of the computer assisted instruction. And analyzed the learning achievement of students after study. The research result revealed that the efficiency of the computer assisted Instruction was efficient in standard 90/90 Moreover after learning achievement at significant level of 0.05.

The purposes of the research were to create computer assisted intruction for Manufacturing process subject to find out the efficency validtion of computer assisted instruction based on the standard of 90/90 and to analyse the students learning achievament after using the computer assisted instrucion. The subjects the study were 17 first-year diploma enploma engineering students enrollong at Rajamangala University of Technology Phra Nakhon. The researcher made the experiment by having the students pretest. The they studied by using the computer assisted instruction foused on practiocing basic turning. After the students had studied and had posttest the efficency of the computer assisted instruction was calculated as well as leaning achievement was analysed. The research resilt revealed that the efficiency of the computer assisted instruction was at the standard of 90/90. Morever the learning achivement after using the computer assisted instruction was different at the singificant lavel of 0.05

This research work was to study the effect of surface treatment of natural fiber and the effects of type and content of natural fiber on the development of acoustic material from natural rubber foam /natural fiber composites. The surface treatment used for this research work was sodium hydroxide (NaOH) treatment. NaOH Concentrations and treatment times were varied from 0 to 15 %wt. and 0 to 30 min respectively. Natural fibers used for this work were bagasse fiber (BF) and oil palm fiber (OPF). The suitable condition for surface treatment was estimated by fiber length and diameter (L/D) ratio and morphology of natural fiber. The result suggested that L/D ratios tended to increase when NaOH concentrations and/or treatment times increased except for NaOH concentration of 15 %wt. L/D ratios of OPF after surface treatment were changed more than those of BF. The suitable conditions of NaOH treatment for BF and OPF were NaOH concentration of 10 %wt. and surface treatment times of 30 and 10 min respectively. The effects of fiber type and content on sound absorption properties of natural rubber foam /natural fiber composites were investigated by cell characteristics sound absorption coefficient DMA analysis and bulk density. Both treated BF and OPF with suitable treatment condition were varied from content of 0.0 to 10.0 %wt. The result showed that the cell size of composites tended to decrease with addition of natural fiber whereas number of foam cell per unit volume increased. After adding natural fiber more than 2.5 %wt. cell size of composite foam and number of foam cell per unit volume tended to change the inverse direction. Natural fiber in composites enhanced the sound absorption efficiency. Sound absorption coefficient of composites adding BF was more than that of composite adding OPF. The addition of natural fiber enhanced the elasticity of composites and that increased sound absorption efficiency. NaOH treatment led to creation of strong interfacial bonding between natural fiber and natural rubber and enhanced the sound absorption efficiency. Density of NR composite foam increased with increasing natural fiber content.