The yield of biodiesel from a base catalyzed transesterification in a batch system is generally low due to the reversed reaction. In addition the process tends to generate high amount of waste water in the washing step. In order to overcome the above problems a continuous process was adopted in this study. Solid alum was used to stop the reaction and filtered off from the biodiesel products. The results showed that biodiesel production from palm oil in a 2.8 liter continuous reactor filled with stainless steel wool acted as a static mixer gave biodiesel of 99.6% purity in 10 minutes at the flow rate of 280 milliliter per minutes. KOH was used as the reaction catalyst at a concentration of 0.75% based on ethanol. The molar ratio of ethanol to oil was 9:1. Three hundred and fifty gram of alum could satisfactorily neutralize one liter of biodiesel.

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.

Design of grounding system to protect against lightning and fault is important for both safety and reliability especially for Metropolitan Electricity Authority (MEA) as mostly Metropolitan Electricity Authority operates on overhead networks. This thesis assesses lightning performance for 69 kV 115 kV overhead subtransmission lines 24 kV distribution line using case study from Metropolitan Electricity Authority. Because of the limitation of the right of way distribution feeders are regularly installed together with subtransmission lines in a single concrete pole. Overhead Ground Wire (OHGW) installed at top of the pole and grounding system in concrete pole protects fault current or direct lightning surge to ground. Metropolitan Electricity Authority has developed lightning protection based on an IEEE standard which uses international data for insulation coordination. As a result reliability of the system is lower than the designed value. This thesis suggests a methodology to improve the performance in order to increase the reliability of subtransmission and distribution lines feeding distribution substations. This thesis recommends installation of addition external ground wire on the outer surface of the concrete pole to reduce top pole voltage and back flashover rate or installation of bundle overhead ground wires to protect shielding failure. As all the case studies presented in the thesis which constitute this thesis are applied to existing systems of Metropolitan Electricity Authority it is expected that the proposed methodologies can be served as useful practical guidelines for lightning performance assessment subtransmission lines and distribution lines of Metropolitan Electricity Authority.

The purposes of this research were 1) to study organic rice production of Praknamdaeng Community Amphawa Samutsongkhram 2) to investigate explicit knowledge of organic rice plantation in Praknamdaeng Community and 3) to discover guidelines on promotion to grow organic rice for food security of Praknamdaeng Community. The population groups were agricultural government officials and Praknamdaeng’s farmers. The research tool was interview analyzed by content analysis. The results revealed as follows: 1) According to organic rice production of Praknamdaeng Community there were 288 hectares (1800 rais in Thai) rice-growing areas and 90 farmers’ families in villages 2 3 4 and 6. The land was full of clay not flooded and in the downstream irrigation area. The weather was humid because it was near the sea. There were many different types of rice varieties grown in Praknamdaeng Community namely; Khao Leuang Patew Chumphon Pathumthani fragrant rice RD 31 Suphan Buri 1 RD 59 RD 47 Sangyod Maung Phatthalung rice Aromatic Black (Hom–nin) rice and Riceberry rice. Rice farming process was mostly taught by villages’ ancestors or experts through learning by doing and working together. The problem of traditional rice growing was soil degradation. The organic rice cultivation in Praknamdaeng Community began in 2005. Khao Leuang Patew Chumphon the loca rice was highly grown. Nowadays 70 percentage of the land was full of GAP organic rice production. The biggest problem for the farmers in the community was drought. 2) As for the appropriate knowledge of organic rice production in Praknamdaeng Community the rice farming processes between traditional and organic rice growing were not different. In the case of organic rice production bio-chemicals were used as herbicides and pesticides but the amount of chemical substances was reduced and only used in a short period for safe. 3) Due to guidelines on promotion to grow organic rice for food security of Praknamdaeng Community there were some guidelines for the 2 groups: farmers and community. The guidelines for the farmers were 1) the pursuit of knowledge or transfer of knowledge to the farmers 2) establishing the learning center of organic rice production in the community by chemical-free cultivation 3) providing organic rice paddy demonstration plot for learning 4) preparing the local people to understand and be volunteers for organic rice cultivation 5) developing farmer organization and 6) promoting comprehensive marketing. The guidelines for the community were 1) in the aspect of the quality of life organic rice consumption has to be promoted for the local people and for food security in the future 2) in the aspect of promotion of farmer career organic rice products can be more value-added make pride and more money for the community 3) systematic community enterprise management 4) support for the networks of producers food processing and distribution of organic rice among other communities and provinces. In the aspect of food security the farmers firstly focus on farmer career stability because they consider it as one of the important careers to produce food to the society. Moreover standard qualified products and suitable demand and supply are included.

The research project investigated the effects of CoO additive on dielectric ferroelectric physical and mechanical properties of modified Bi0.5(Na0.81K0.19)0.5TiO3 ceramics were investigated. The samples were synthesized by solid state reaction technique where powders were calcined at 850 °C for 4 h and ceramics were sintered at 1050 °C for 4 h which difference heating rate controlled i.e. 100 300 and 600 °C/h for. The ceramics of BNKT/x wt.% CoO was added CoO by various x=0.00 0.10 0.20 0.30 0.60 and 0.90. Phase formation was determined by X-ray diffraction technique (XRD). The X-ray diffraction analysis of the ceramics suggests that all samples exhibited a perovskite structure. The dielectric properties under room temperature and various temperatures were also determined. Dielectric measurement data showed that the additive and heating rate controlled influenced dielectric constant and dielectric loss. Furthermore the hysteresis loop behaviors slightly changed with increasing the CoO contents.