จำนวน Repository ( 3447 )
The design and construction of shell and tube heat exchangers for use in the manufacture of Ice
This paper presents a study of heat exchanger design for improving the performance of ice maker by using waste water from ice factory. The heat exchanger was made of stainless steel and had 4.023 m2 of heating surface. After using the heat exchange in the waste water pond which the temperature was 0 C the temperature of feed water was decreased from 28 C to 22 C. The COP of the ice maker was increased and the factory can save energy consumption 52034 kWh/year or 61993 baht/year. The payback period was 0.5 year
The input power factor control of a carrier-based dipolar PWM for matrix converters
This paper presents the input power factor control of a modulation using a carrier-based dipolar for matrix converters by determining the optimum value of free parameters b and d in general solutions of the modulation matrix. The proposed PWM method is not only less complicated but can clearly show the coupling of the input power factor control from both active and reactive output power. The experimental results show that the proposed PWM method can control the conditioned input power factor set earlier
Electronic marketing communication towards buying decision behavior
The study of Electronic Marketing Communication Towards Buying Decision Behavior which aims to research the consumer behavior in term of receiving message through electronic marketing communication channels. The research compares several channels of electronic marketing communication that lead to buying decision. The method is information collecting from 400 targeted respondents and data analysis by SPSS statistical program. Respondents selected the following electronic marketing communication which is the best tool for buying motivation respectively: The information search through internet by Search Engine system reason: convenience of use
Exciting permanent-magnetic-field affecting to the bean sprout growing
The purpose of the research was to study the exciting permanent-magnetic-field affecting to the Bean Sprout growing. The comparison of control-group (or unexcited seed) of the Chainat-72 seed and exposure-group seed where is the excited by the 1.6-Tesla permanent-magnetic-field of 15 30 45 and 60 min has been done. The exciting permanent-magnetic-field affecting to the Bean Sprout growing is analyzed by statistical analysis. The findings revealed that: by excited seed the maximum grow-up rate or average weight of Bean Sprouts was 24.82 %.
An induction furnace with half bridge resonant inverter for brass
This research presents the design and construction of molten brass to form the basis of induction heating. It is heated by the half-bridge voltage source in series resonant load by transferring the heat energy through the graphite crucible for 300 grams melting of the brass in 10 minutes. The system is controlled to operate at a higher frequency than the resonance frequency mode with the input three-phase AC voltage 380 V 50 Hz through a rectifier into a DC voltage to be supplied to the inverter supply voltage half-bridge about 35 kHz switching frequency at the rated power 4.5 kW