This research is aimed to establish the small wireless sensor network under the real environment. The objectives this research is aimed to study the data transmission and evaluate the data transmission performance of RPL protocol in wireless sensor network. Four nodes of wireless sensor network have been installation and transmissions between nodes in single-hop and multi-hop have been simulation for testing and analyzing data from the network following the transmission performance index. The research found that the number of hop and building environment are the principle factor to the performance of RPL protocol this might be the major limit to implement the RPL protocol in wireless sensor network

The objectives of this research were to prepare the syrup from the extracted yam bean and apply this syrup for adjusting the sweetness in the orange flavor drinking yogurt. The study made a yam bean extract concentrated by 3 difference heating methods; steaming boiling and boiled-evaporating. The results showed that a proper method was boiling yam bean extracted at a temperature of 90°C for one hour. The syrup was light brown color and not very strong smell of yam bean the total soluble solid was 20 °Brix and the non-reducing sugar content was 17.80 %. The drinking yogurt which was formulated using a ratio of set yogurt: orange juice (100%): yam bean syrup at 1:1:1 had the sensory properties (9-Point Hedonic Scale) higher than the ratio of 1:1:0.5 and 1:1:1.5 (p≤0.05). This drinking yogurt had a pH at 4.2 the total soluble solid was 15 °Brix protein was 1.75 % fat was 2.1% and non-reducing sugar content was 5.39 %. The microbiological properties passed quality standards (drinking yogurt) of Notification of the Ministry of Public Health No. 353 B.E 2556. The study of consumer acceptance on the drinking yoghurt with yam bean syrup showed that consumers had a preference for the product at like - most like level at 72 % acceptance on the product at 97 % and would buy this product at 76 %.

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 purposes of this research were to investigate anaerobic digestion of concentrated food waste in biogas production system at mesophilic temperature (37 C). The effect of grinding and pH controlled at 6.20 and 7.00 on methane production were also studied. It was found that the ability of mix bacteria which had initial concentration of 2100 mg/l for digesting concentrated food waste with grinding was higher than that without grinding because of the increase in surface area (about 1.37 time). In this system the optimum condition for bacteria growth was found at pH 7.00. Under optimal condition the digestion efficiency in term of chemical oxygen demand (COD) removal was 18.81% higher corresponding to an increase in methane production rate (19.10%) than other conditions