The objectives of this study is to increase efficiency of steam boiler 2.5 ton per hour which used liquid petroleum gas LPG as fuel. bringing heat recovery inside boiler chimney stack to preheat feed water with technology heat Exchanger Economize. Taking the economizer with its pipe length of 1000 mm and 62 mm diameter for 64 pipe is a cross flow with staggered tube to increase water temperature before entering the boiler pass to deaerator The study is carried out to compare the differences and savings of the feed water temperature steam boiler efficiency and fuel consumption between having the economizer installed and uninstalled. reference to study The result after installed the heat exchanger economizer the feed water is passed into steam boiler deaerator higher temperature from 38.30°C to 67.20°C which leads to increase efficiency of steam boiler from 81.59 % to 85.65 % meaning that the fuel consumption of steam boiler will be reduced 4.97 %

Admittedly a disc brake plays an important role in the auto part industry since it concerns directly with safety. Therefore the wide range of disc brake has been designed in order to develop its heat ventilation. There are two physical kinds of brakes: front-vented disc brake and backvented disc brake. As a result such difference affects directly to the heat ventilation which is a vital factor of the brake’s capability. The project team recognizes its importance and tries to create the test to find out the temperature diffusion of the disc brake with the hope to evaluate the coefficient of the heat convection varied by the temperature changing in both kinds of brakes under the forced heat convection in the steady condition. However the steady heat conduction and radiation value will not be counted because it is insignificant. The JASO C406: 2000 Standard is adopted as a guideline in the test. The outcome coefficient of heat conduction will be used in the simulation via the Finite Element Method (FEM) in order to study the temperature diffusion and heat ventilation of both kinds of brakes at each temperature level. Consequently the experimental work reveals then the heat convection coefficients of both kinds are unidirectional. The heat convection coefficient of the front-vented disc brake is 4.40 % in average higher than that of the back-vented disc brake. From the simulation the front-vented disc brake can ventilate the heat better than the back-vented disc brake at 3.02 % in average. It can be summarized that the front-vented disc brake has more temperature difference than the backvented disc brake. Hence the front-vented disc brake likely gets more stress from the temperature than the back-vented disc brake and might be damaged during the operation more than the another type.

Nowadays one of the automotive engineering is conductivity of brake pads playing a role in friction coefficient which means safety of customer. Thus thermal properties have been improved using composited materials. This project aims to study the conductivity behavior of 3 different brake pads which are supported by the company Compact International (1994) Ltd. For experimental works temperature based on brake condition was simulated from 200 to 400°C and cooled down from 400 to 200°C at 1 5 and 8 MPa of pressure respectively. By standard JIS D4413 testing condition of pressure was referred. The non-linear of conductivity value are calculated from the temperature under steady state condition. As a result of testing there are several of parameters effecting on the non-linear conductivity value. The brake pad that is a mix of high-fiber occurs the fluctuation of thermal conductivity. At the same time lubricant in the brake pad cause the stability of conductivity value in different temperature range at the same pressure. On the other hand the brake pad mixed hi-copper inspires the narrow range of conductivity value in different pressures at the same temperature. Moreover the conductivity value as a mention is inversely proportion with the coefficient of kinetic friction.

The research objective is to utilize the waste water at 12ºC to 20ºC in exchange with the process water at the temperature of 29ºC. After entering the heat exchanger the process water will have the reduced temperature of 19ºC and then will be delivered to the cooler so the temperature of the process water will further be reduced to 15ºC to involve in the production process. Consequently the cooler’s energy use is lower. Since the common coolers used in these days have problems about the clogged system caused by shrimp residue the cleanup of the system is difficult and the maintenance cost is high. With this problem the research and development of the new heat exchanger is carried out resulting to the Shell and Tube Heat Exchanger type with the angled lid and the waste water flow control pads allowing the water alternatingly running through the lower part and upper part of each pad. The process water will flow in the 6 sets of the stainless tubes with 2 mm. thickness ½ inch diameter and 6 meter length. The space between the set is 5 centimeters for exchanging heat with the waste water flowing outside the tubes. The study conclusion is that the new heat exchanger can reduce the temperature of the process water to 19ºC so it can save the electricity cost of the cooler for 886485 baht per year and make the cleanup easier without taking off the equipment parts thus lowering the maintenance cost as well.

This research conducted an investigation on vocational pre-service teachers’ performance based on Technological Pedagogical Content Knowledge Framework (TPCK) to support learning in 21st century. TPCK Framework integrated three kinds of knowledge needed by a teacher in providing learning process for students effectively. The results of this study found that vocational pre-service teachers had the knowledge of using technology understanding teaching pedagogies and mastering on content individually. However they were limited in blending such essential three domains together to form more effective learning process for their students.