This paper presents about the defrosting time of evaporator in refrigerator by using the temperature different between evaporator and chilling area. This temperature different concept could control the defrosting system to operate according to the load. It also helps controlling the operation of fan motor to be able to operate in accordance with the defrosting time. In general system the timer is set at the highest humidity season which cause the unneccessary defrosting cycle even in low humidity season. This general system create the west of power usage colling system. These can cause time-consuming in defrosting process in the low humidity season and cause the unnecessary usage of power to cooling system. This research is to develop the controller for the defrosting system at evaporator from the investigation. As the results we have found that the defrosting system at evaporator according to its load made the refrigerator can decrease the power about 8% when comparing to constant time evaporator system

The objective of this research is to propose method for optimization route selection by Analytic Hierarchy Process (AHP) and The Technique for Order Preference by Similarity to The Ideal Solution (TOPSIS) model. The model was applied to case study route selection from Laem Chabang Port in Chonburi to Bangpoo Industrial Estate in Samut Prakan based on the criteria: cost of transportation transit time risk of freight damaged risk of infrastructure and equipment and risk of other factors. AHP was used to determine the relative weight of criteria. Additionally TOPSIS was used to select the best alternative routes. The result showed that the AHP-TOPSIS model which is new approach for route selection flexible decrease discrepancy from weighting more efficient than one either AHP or TOPSIS and not too complicated models compared to the other methods in multiple criteria analysis.

The purpose of this research was to construct the appropriate forecasting model for the prices of field corn in Thailand using four time series analysis methods including Box-Jenkins method Holt’s exponential smoothing method damped trend exponential smoothing method and combined forecasting method. Time series data from the website of the Office of Agricultural Economics with total 227 months during January 1997 to November 2015 are used and divided into two series. The first 216 months from January 1997 until December 2014 used to build the forecasting models and the last 11 months from January until November 2015 used to compare the forecasting methods accuracies via the criteria of the lowest mean absolute percentage error and root mean squared error. Research finding indicated that combined forecasting model was the most accurate.

The research aims to study the quality of Chaiya salted eggs coated with tea waste to partially replace soil from termite mound. The residue of tea waste dried to a moisture content of 14.9% was used to prepare salt coating paste. It was found that the mixture of coating paste by substitution of termite mound soil with 10% (w/w) tea waste was appropriate to coat the duck eggs. The salt content increased in both egg yolk and egg white with increasing salt coating time. Coating egg with 10% tea waste for 24 days egg yolk contained salt 0.83% moisture 17.04% and weighed 19.19 grams. The pH value and hardness were 6.43 and 93.67 gram respectively. The egg white contained salt 5.27% moisture 81.61% and pH value was 7.60. The salted boiled eggs coated by 10% tea waste treatment for 21 days were accepted by the panelists in terms of the overall liking with the level of much liking (8.67) not significantly different (p>0.05) from that of the control treatment (0% tea waste). Microorganisms in the salted boiled eggs did not excess Thai OTOP standard. A hundred general consumers accepted this product in terms of the overall liking with the level of much liking (8.00).

The objectives of this study were to calculate the probability of type I error power of a test and to compare the performance of three test statistics: Z Student’s t and Welch’s t. Including the recommending the appropriate test statistic. Classification of the population according to five distribution. The ratios of mean group 1 per group 2 were three levels. The ratios of variance group 1 per group 2 were three levels. The sample sizes of two populations were nine sizes. The significance levels that to study were 0.01 and 0.05. The data were simulated by using SAS programming with 1000 replicates. Results of the research were Z test statistic could control the probability of type I error and had higher power of a test than other test statistics but this test is necessary to know the variances of the two groups. Therefore it was appropriate to apply the other test statistics i.e. Student’s t or Welch’s t. If the variances of the two groups were equal Student’s t was a more appropriate test statistic than Welch’s t. But if the variances of the two groups were not equal Welch’s t was a more appropriate. When both sample sizes were large and the population variances were equal we could use any tests since there is no difference in the performance.