จำนวน Repository ( 3611 )

การจำแนกประเภทเมล็ดข้าวขาวด้วยการประมวลผลภาพ
การจำแนกประเภทเมล็ดข้าวขาวด้วยการประมวลผลภาพ

This research work presents the development of algorithms and programs used for classifying of white rice grains obtained from the camera by using image processing techniques. This procedure begins with improving input images converting color images to binary images by setting the threshold value automatically by using the Otsu’s method noise filter process image processing with structural elements that form a square determining the grain boundary by using the Canny’s operator determining the length of the grain by using the Euclidean’s method. Next the length results of the grains have been obtained from the decision process based on the Rice Standards of Thailand (RST) in order to receive the type solutions of tested white rice. From the testing results for 800 images it has been shown that in case of 500 images the developed program provided the mean absolute error of the grain length of 0.01 mm per grain. Moreover for testing of 300 images the developed program provided the separation accuracy of the grains up to 99.33% in term of the RST. This can be useful in determining the price of white rice in a rice mill with farmers.

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การเพิ่มประสิทธิภาพเครื่องปรับอากาศแบบแยกส่วนโดยใช้ลมเย็นจากพัดลมระบายอากาศ
การเพิ่มประสิทธิภาพเครื่องปรับอากาศแบบแยกส่วนโดยใช้ลมเย็นจากพัดลมระบายอากาศ

This research aimed to find the possibility of increasing the efficiency of the split type air conditioner by using the cool air from a ventilation fan in the air conditioning room for cooling the condenser. Two simulation rooms size 120x120x200 centimeters were constructed. The first room was installed the evaporator and the second room was installed the condenser and a ventilation fan in the lower part of the air conditioning room to deliver the cool air for cooling the condenser. Then the system was tested and compared the energy efficiency ratio and the reduced power consumption between turning on and turning off a ventilation fan. The results of the proposed air conditioner system observed from the various load conditions at 0% 30% 60% and 100% The surrounding temperature of the condenser ranged in 30C 40C and 50C It was found that the energy efficiency ratios increased in the range of 2.94% to 5.92% and the power consumptions decreased in the range of 4.56% to 12.5% The possibility of increasing the efficiency of the air conditioner system by using the cool air from ventilation fan in the air conditioning room for cooling the condenser was verified by the increased energy efficiency ratios and the reduced power consumptions.

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อันตรายด้านจุลินทรีย์และจุดควบคุมวิกฤติการผลิตอาหารโรงเรียน : ข้าวคลุกกะปิ
อันตรายด้านจุลินทรีย์และจุดควบคุมวิกฤติการผลิตอาหารโรงเรียน : ข้าวคลุกกะปิ

The objectives were to study microbiological hazard of Khao kluk ka pi for school food service risk assessment and critical control points (CCP) according to HACCP principles.The production of Khao kluk ka pi had the improper hygienic practice. Thus TPC counts were found in shallots coriander and chilli at 1.9×106 3.2×107 and 5.9×106 cfu/g respectively and found E. coli in chopped coriander more than 1100 MPN/g. The TPC S. aureus C. perfringens Salmonella and V. parahaemolyticus were not detected in cooked ingredients. The number of TPC in Khao kluk ka pi held at ambient temperature for 0 2 4 and 6 hours were founed an increase from 1.2×106 cfu/g to 7.6×106 1.8×107 and 3.4×108 cfu/g respectively that was as a result of the uncooked ingredients and mixing process. The microbial numbers were increased when this food was held for a long time before serving. The CCP of Khao kluk ka pi production were indicated at the process of washing raw vegetables cooking process and holding cooked food at room temperature for a long time before serving.

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การพยากรณ์ปริมาณการส่งออกเนื้อไก่แช่แข็งและแช่เย็น
การพยากรณ์ปริมาณการส่งออกเนื้อไก่แช่แข็งและแช่เย็น

The purpose of this research was to construct an appropriate forecasting model for the export quantity of frozen and chilled chicken using three time series analysis methods including Box-Jenkins method Holt’s exponential smoothing method and damped trend exponential smoothing method. Time series data from the website of the Office of Industrial Economics with total 130 months during January 2004 to October 2014 were used and they were divided into two series. Fristly 120 months from January 2004 to December 2013 were used to build the forecasting models and lastly 10 months from January until October 2014 were used to compare the forecasting methods accuracies via the criteria of the lowest mean absolute percentage error and root mean squared error. Research findings indicated that all forecasting methods that had been studied damped trend exponential smoothing method were the most accurate method and showed the forecasting model as where m represented the number of periods to forecast ahead with the starting value was January 2014 (m = 1).

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การทำนายอัตราการถ่ายเทความร้อนในเงื่อนไขสถานะชั่วครู่ของเครื่องแลกเปลี่ยนความร้อนชนิดท่อความร้อนโดยใช้แบบจำลองสามมิติ
การทำนายอัตราการถ่ายเทความร้อนในเงื่อนไขสถานะชั่วครู่ของเครื่องแลกเปลี่ยนความร้อนชนิดท่อความร้อนโดยใช้แบบจำลองสามมิติ

The aim of this study was to develop a three-dimensional transient condition model to predict the heat transfer rate of a heat pipe heat exchanger. This paper presents the details of the calculated domains which consist of the wall wick and vapor core. They were numerically simulated using the finite element method. The heat transfer rate values obtained from the model simulation can be used to design heat pipe heat exchangers. The values obtained from the model calculation were then compared with the results from experiments and the differences were 10.3% 10.4% and 6.7% for the working fluids of distilled water ethanol and R134a respectively. The working fluids of distilled water ethanol and R134a obtained heat transfer rates of 627.3 watts 522.8 watts and 836.4 watts from the experiments respectively.

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