จำนวน Repository ( 1852 )

สมบัติทางเคมีกายภาพ ทางกล และทางความร้อนของฟิล์มบริโภคได้จากแป้งมันเลือด
สมบัติทางเคมีกายภาพ ทางกล และทางความร้อนของฟิล์มบริโภคได้จากแป้งมันเลือด

Man Lueat (Dioscorea alata) flour is a biopolymer material that can be formed into an edible film. It can be contacted directly with food consumed and naturally biodegraded. The aims of this research were to study the effect of physicochemical mechanical and thermal properties of edible film from Man Lueat flour. The film forming solution was prepared by Man Lueat flour at 4% w/w. The glycerol was used as a plasticizer. It was studied at 3 different levels; 30 40 and 50% w/w of Man Lueat flour. The film forming solutions were formed using the solution casting method and dried at 50 °C for 16 h. Results showed that the glycerol content at different levels of the edible film from Man Lueat flour had no effect on the thickness color transparency and elongation at break. However the moisture content water solubility swelling property and water vapor permeability of the film tended to increase when increasing the glycerol content. In contrast the Young’s modulus and tensile strength of films tended to decrease significantly when the glycerol content increased. Thermal properties were found that decomposition temperature of films occurred 2 stage; the first stage occurs between 50 to 130 ° C and the second stage occurs between 263 to 315 ° C. The analysis of FT-IR showed that the different levels of glycerol affected the structure of the film (3278 cm-1). Therefore the edible film from Man Lueat flour can be applied as a food packaging material to protect the quality of food products.

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การพัฒนาต้นแบบเครื่องยนต์ที่ใช้น้ำมันดีเซลและแอลพีจีเป็นเชื้อเพลิงสำหรับการเกษตร
การพัฒนาต้นแบบเครื่องยนต์ที่ใช้น้ำมันดีเซลและแอลพีจีเป็นเชื้อเพลิงสำหรับการเกษตร

According to the research entitled “the innovative engine prototype powered by diesel and LPG as fuel for agricultural” in 2019 the problems found while using the engine were as follows: the accumulated heat in the auxiliary combustion chamber reached 300 C in case of gasoline engine use and a lot of black smoke in the exhaust was found at the speed higher than 1800 rpm in case of a diesel engine use. In order to extend the research and solve two foresaid problems the objectives of this study were 1) to develop an auxiliary combustion chamber for cooling 2) to develop a scalable gas-air mixing device and 3) to compare diesel and LPG consumption rates by modifying a small diesel engine Yanmar version TF120DI to install LPG fuel systems and ignition system. In addition a gas-air mixing device was modified while an auxiliary combustion chamber was developed to reduce the compression ratio to the same level as the gasoline engine for replacing the position of the original diesel fuel injector. This method could support LPG fueling only whose function was characterized by the function of a gasoline engine. The auxiliary combustion chamber could be removed and then installed a diesel injector to return using diesel fuel. From an experiment to compare the modified engine operating as a gasoline engine it was found that the temperature of the auxiliary combustion chamber and the temperature of the engine cylinder head of Honda GX160 were measured at the maximum speed of 182 C and 186 C respectively. It was found that carbon monoxide content was 0.41 % and 1315 ppm hydrocarbons. When used as a diesel engine it was found that the black smoke was exhausted at 1.5 % which was similar to the diesel engine before the modification. From the experiment of using the power engine for pumping water with an Irrigation propeller pump with the diameter of 8 inch at a constant engine speed of 1000 rpm it was found that the average diesel usage was 0.65 kg/hr or about 0.77 L/hr with the cost of 21.00 Baht/hr and if using LPG as fuel the average LPG consumption was 0.57 kg/hr with the cost of 13.71 Baht/hr which could save up to 34.71 % of costs.

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การวิเคราะห์ปริมาณสารสำคัญและฤทธิ์ต้านอนุมูลอิสระของสารสกัดใบกะเปียดเครือ
การวิเคราะห์ปริมาณสารสำคัญและฤทธิ์ต้านอนุมูลอิสระของสารสกัดใบกะเปียดเครือ

Premna trichostoma Miq. (Lamiaceae) mainly distribute in Asia including Thailand. Folk healers use this plant to treat fever as a juice splash and bathe. The aims of this study are to evaluate the quantity of active constituents and antioxidant activity of P. trichostoma leaf extract. Total phenolic compounds were determined using Folin-Ciocalteu method. Total flavonoid contents were determined by Aluminum chloride method. The amount of apigenin and kaempferol contents were analyzed by high performance liquid chromatography (HPLC). In addition the antioxidant activity was evaluated by DPPH and ABTS assay. The results showed that total phenolic contents total flavonoid contents and the amount of apigenin and kaempferol of P. trichostoma leaf extract was 46.45±15.30 mg GAE/g extract 25.48±2.02 mg CE/g extract 11.16±0.04 and 4.54±0.08 µg/g extract respectively. The IC50 values from the DPPH and ABTS assay was 117.50±1.22 and 36.14±1.53 µg/ml respectively. This study shows the antioxidant properties and active constituents of P. trichostoma leaf extract which indicates the potentials for further development of this plant

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การควบคุมคุณภาพและลดการสูญเสียในกระบวนการประกอบชิ้นส่วนบังโคลนหน้าแก้มข้างรถยนต์ด้วยวิธีโพคา-โยเกะ
การควบคุมคุณภาพและลดการสูญเสียในกระบวนการประกอบชิ้นส่วนบังโคลนหน้าแก้มข้างรถยนต์ด้วยวิธีโพคา-โยเกะ

This study aimed to use Poka-Yoke techniques to help prevent errors and reduce loss in Front Side Fender Model assembly process. The researchers used four tools in the 7QC tools which were Check Sheet Cause-and-Effect Diagram and Graphs to search for causes and ways to solve problems and Cause and Effect Matrix and ECRS Techniques. The study revealed that the main cause of the problems was that the incorrect assembled side fenders were submitted to another department. This mistake had bad effects on time and workforce spent for correcting work including more expenses. The mistakes occurred because there was no tool for detecting errors in the work piece. Therefore the researchers use Poka-Yoke techniques in order to decrease errors by designing a control system for target detection while it was moving through the process. After collecting data the study showed that before the improvement during January to August 2019 the number of problems caused by the process were 0.093. However the number of problems after the improvement during September to December 2019 reduced to 0. It was obvious that this improvement reduced the loss from the front side fender assembly process up to 100.

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Real-time travel time prediction algorithm using spatiotemporal speed interval patterns matching
Real-time travel time prediction algorithm using spatiotemporal speed interval patterns matching

Accurate efficient and robust travel time prediction is crucial to the development of advanced traveler information systems for providing route guidance information. To achieve this goal this paper proposed a travel time prediction through the matching of the current speed interval pattern to that in a historical database. Speed intervals instead of speeds are considered in this study to simplify the structure of matching patterns for improving matching efficiency. In this study speed interval patterns are defined by sets of link speed intervals that are either spatially or temporarily correlated with the link considered. With the speed interval patterns the algorithm is developed for searching the historical pattern(s) that is/are the closest match with the current one. Then link speeds from these matched patterns are combined for travel time prediction. By using the GPS probe taxi data which the collected speeds are aggregated in every 5 minutes the proposed travel time prediction system is implemented in Bangkok. With the speed data from probe taxi this paper has chosen four links/paths with different geometric and flow characteristics for testing the performance of the proposed travel time prediction system. From these tests it is found that the optimal speed interval pattern should include: 1) speeds of the studied link within three preceding time intervals and; 2) speeds of links in the first connection level of the studied link. Also while the computational time is capable of real-time application the proposed prediction algorithm is more accurate under uninterrupted flow conditions.

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