This research aimed to study the optimum factors affecting the quality of gold plating process to enhance OTOP knife products of Ban Mai knife forgers village. This study focused on application of AISI 5160 steel and the 24k gold plating process.In the experiment three samples of plating currents were observed; 10 12 and 14 volts each at 30 60 90 120 150 seconds and 180 seconds respectively. The study found that applying the electric currents in gold plating at 12 volts for 120 seconds gave the best results for the gold color and thickness by giving the thickness of the gold surface at 33.82 micron and the color value between L*=88.72 a*=4.45 and b*=78.58. Moreover the gold dispersion was consistent throughout the workpiece. From applying the electric currents in gold plating at 10 volts it lessened the thickness of the gold plating which made the gold plating look uneven. From applying the electric currents in gold plating at 14 volts it increased the thickness of the gold plating which resulted in a dull or burned finish from over-plating. In comparison the cost of the knife before plating with gold costs only 30 baht per piece while the cost of the knife after plating with gold costs 99 baht per piece. In conclusion the daily sales of a product increase from 50-60 items per day to 60-75 items per day which also resulted in increased revenue and profitability from 1500-1800 baht per day to 5940-7425 baht per day on average.

This research objective was to determine physical and aerodynamics properties of Khao Dawk Mali 105 paddy (Thai Jasmine paddy rice). The paddy sample in this test was prepared with different moisture contents in the range of 10-26%WB and air temperature in aerodynamics properties test was varied in the range of 50–100 OC. Test results were analyzed to determine the statistical mean difference by DMRT method (at P<0.05). It found that moisture content in paddy affects the difference of average length width and thickness of grain and results the difference of geometric mean diameter and degree of sphericity of paddy. An increase in paddy moisture results the increase of average bulk density and kernel density but it reduces the porosity of paddy. Moisture content in paddy affects the difference of terminal velocity. Moisture content in paddy and air temperature influenced the difference of average drag coefficient of paddy.

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 aimed to study the use of coarse aggregate obtained from removing old recycled asphalt pavement (RAP) in the production of the porous concrete paving block. Crushing and size separation of the coarse aggregate by using standard sieve size by selected the gradation size of the coarse aggregate that passed to sieve size 1/2” and retained on sieve size 3/8” and other that passed to sieve size 3/8” and retained on sieve size No.4 by mixing ratio 50 : 50 of the mass as replaced natural coarse aggregate. Portland cement quantity about 18% and 20% by weight of the aggregate. The water to cement ratio was 0.30 and 0.35 respectively. Compressive strength flexural strength and water permeability were investigated. The results showed that the cement content and water to cement ratio was influenced the strength properties and water permeability rate of the porous concrete paving block. The porous concrete paving block mixed with higher cement content (20%) had the compressive strength at the age of 28 days increased by 16-24% when compared with lower cement content (18%). On the other hand the water permeability rate decreased by 5.1-8.1%.

Development of chili powder products through consumer survey to be used as the information for the development of high quality chili powder. The quality and physicochemical properties of chili powder during storage were investigated. The sound and red pods of fresh chili were washed and blanched at 100ºC for 3 min. Blanched chili pods were soaked in 0.25% sodium metabisulfite with 1.0% citric acid for 30 min prior to drying in a tray dryer at 65°C for 14 h to obtain dried chili with a final moisture content of approximately 8%. Dried chili pods without stem were ground to obtain chili powder. Roasting before grinding resulted in the reduction of moisture aw and color values. The results of study on the quality changes of chili powder during storage showed that storage temperature was the important factor affecting the changes in physicochemical properties and percentage of consumer acceptance. Meanwhile aluminum foil packaging slowed the increase of aflatoxin content in chili powder better than polypropylene. However aerobic bacterial count of the developed chili powder product is very low compared to the microbiological specifications while yeast and mold were not detected. The product contains a standard level of aflatoxin content after 12 weeks in all storage conditions which corresponds to the awareness of consumers in terms of quality cleanliness and safety are important factors in deciding to buy chili products.