This paper presents the design of a power harvester for passive RFID Tags. An impedance matching circuit chooses a high-pass L network inserted between the antenna and rectifier circuit to maximize the power transferred to Tags using an impedance transformation technique. A simple circuit including only a shunt inductance was selected as a matching. The rectifier utilizes a Self-Vth-Cancellation (SVC) circuit is an archived self-threshold voltage cancellation and self-power regulation function with a simple circuit design. An antenna is modeled as an RF source with a series impedance Zs of 50Ω while the rectifier is modeled as a load impedance ZL which is estimated from the process and design parameters of the NMOS and PMOS transistors used in the SVC rectifier. As the combined circuit was simulated using input in the UHF band of 953 MHz and the devices’ model of the 0.35μm CMOS technology. The simulation results were compared with the single-stage rectifier of the SVC technique in the issue of the Power Conversion Efficiency (PCE). The achieved DC output of the rectifier yields the power conversion efficiency of 43.7% at input RF power -10.22dBm while a DC output voltage of around 643.8mV and a current load of 64.4μA.

The purpose of this research were to 1) study the production factors and efficiency of fireproof suit; 2) analyze the three line balancing models of fireproof suit; and 3) make comparison of production efficiency for fireproof suit’s manufacturing processes. A group of representative sample for assessments is 90 dressmakers of Creative Polymers Co. Ltd. The used tool for collecting data is the data recoding form consisting of production process list data recording date processing operation and duration of processing. Accordingly put the sewing line layout and make production test with the three line balancing models of fireproof suit then record all data and entry all data to SPSS program to average statistics on percentage and standard deviation. The research showed that the improvement of the three line processing models of fireproof suit comparing to the data of the three line balancing models are identified that C model increased from traditional production system 74.05 percentage B model increased from traditional production system 57.51 percentage then A model increased from traditional production system 48.53 percentage. The result showed that the fireproof suit’s production processing of Creative Polymers Co. Ltd. ought to take the C model in order to fasten production process and augment better quality. A minimum process of producing is amount of 110 steps with less time per one unit; minimum 177.41 minutes; with 30 workers; and 27 machines. The waste product of the three line processing models: A B and C model; not over 20 percentage during 8 hours of working. It shows that the c model has the least of waste product. The over operation that product has not much wasted not include in choosing the model for improving production efficiency and C model

The purpose of this research was to investigate cooling water profile that effect to coefficient of performance of spilt type air- conditioning system. Air conditioner size of 12000 Btu/h was used in this experiment. There are three experiment of cooling water profiles in this work such as water spray water drop and heat exchanger profile. The ambient temperature conditions were controlled at 35 40 43 and 45 oC. The results of this study were found that heat exchanger profile had the highest average coefficient of performance and energy efficiency as 4.94 and 9.15 Btu/Wh which increased as 20.1% and 8.47% respectively when comparing with the normal working.

At present a problem found in the soft candy producing process in the food producing department of Company Case Study is time-consuming roller washing process due to an ineffective washing process. A roller is washed one by one from a total of 10 roller (a set) in one machine. As a result the operation rates of other producing processes have been forced to delay. The objective of this research is to resolve the problem found in the process of roller washing by designing a machine for washing a set of roller per time. The research begins from examining design concepts of roller washing machine from patents and the current quantity of water and stream used for washing before conducting design of a new soft candy type roller washer machine. And eventually the efficiency of new roller washer machine is compared with current one. The findings indicate that the newly developed design can reduce washing period from 24.48 minutes/set to 5.56 minutes/set and increase operation time by 18.92 minutes or accounting for 77.28 percent. Meanwhile water quantity used in the process is reduced from 124.82 liters/set to 28.35 liters/set and stream quantity used in the process is also contracted from 0.83 kilogram/hour/set to 0.18 kilogram/hour/set. This reduction can save expenses equal to 28795 baht/year. As the budget for making new roller washer machine is 53000 baht and payback period is only 1.84 year.

This purpose of the research was to study of Solar Absorber Shape Effect in the Solar Air Heater. These has designed and constructed the solar air heater for drying agricultural products of two different types. Comparison of First thing used square type one glass layer used centrifugal fans to feed air and installed solar absorber which each made of sinusoidal corrugate galvanized steel sheet coated with dull black paint and each other made of trapezoidal corrugate galvanized steel sheet coated with dull black paint. The results of research showed that the solar absorber which each made of trapezoidal corrugate galvanized steel sheet coated with dull black paint is most suitable. Which has overall thermal efficiency 66% and can generate maximum temperature 96.13 degree of Celsius