Engineering Transactions: A Research Publication of Mahanakorn University of Technology

Waste Reduction in Packing Process of Coloured Pencils

2023-08-03T14:19:27+07:00

This research aims to reduce waste produced during the packing process of coloured pencils. Cause and effect diagram was applied as the tool to find the causes of the waste in the a packing process. There were three main causes of waste: delay, motion and defect. Delay and motion, method and workspace were analyzed. It was found that the arrangement of the crates was not proper and the positioning of the crate and boxes was unclear. These led to employees intervened because of using their eyesight to find coloured pencils in boxes. Defect, positioning equipment was investigated. It was found that the equipment was inefficient. These 3 issues were solved by adjusting the layout of the packing process with the application of FSN analysis of warehouse management and improving the positioning equipment by applying engineering design theory. The results showed that the waste of the delay of 12 coloured pencils was reduced from 0.93 second per box to 0.54 second per box, representing 41.94 percent of decrement, or reduced from 579 seconds per cycle to 338 seconds per cycle, representing 41.62 percent decrease. For 24 coloured pencils, the waste of the delay was reduced from 3.42 seconds per box to 1.87 seconds per box, representing 45.03 percent of decrement, or reduced from 1148 seconds per cycle to 629 seconds per cycle, representing 45.21 percent of decrement. Futhermore the waste of the motion of 12 coloured pencils was reduced from 254.33 meters to 109.61 meters, representing 56.90 percent of decrement. For, 24 coloured pencils, the waste of the motion was reduced from 359.41 meters to 218.33 meters, representing 39.25 percent of decrement. Finally, the waste of the defect of 12 coloured pencils was reduced from 0.24 percent to 0.12 percent, representing 50.00 percent of decrement. For, 24 coloured pencils, the waste of the defect was reduced from 0.39 percent to 0.13 percent, representing 66.67 percent of decrement.

Application of Fuzzy Logic Algorithm with Image Processing for PVC Socket Inspection

2023-08-15T14:18:52+07:00

This paper proposes the PVC socket inspection using application of fuzzy logic algorithm and image processing in LabVIEW programming. The image processing to find information such as area of objects in pixel and area of objects per area of frame in percent. The fuzzy logic algorithm utilizing TSK's method. The experiment results show inspection accuracy of PVC equal tee, PVC elbow 90 degree and PVC coupling between 92 percent and 94 percent.

Design of gasket surface extrusion equipment

2023-09-12T17:19:41+07:00

This research aims to reduce time in gasket production of case study company A. This research applies work study for determining the operation standard time. In deep analysis of time study, the data reveals that preparing surfacing extrusion process is the main problem because it takes the longest processing time and lot of work force. Therefore, the principles of tool engineering and design theory to analyze the designs, determine dimensions, and select materials for each part under the constraints of the workpiece and practical use in the design of auxiliary equipment for gasket surface extrusion. Next, the proposed equipment is tested in real operation. The results indicate that the proposed equipment can be applied efficiently for this process and reduced the surfacing extrusion process time significantly from 4.30 minutes to 2.20 minutes and reduced the gasket production time from 11.35 minutes to 9.76 minutes.

Investigation of heat transfer in a rectangular duct fitted with V-shaped baffles

2023-10-27T17:54:09+07:00

The present research investigated heat transfer in a rectangular duct with V-shaped baffles by using air as the heat transfer fluid. The V-shaped baffles were fabricated from twisted tapes having twist ratios (y/w) of 2, 3, 4, and 5. The baffles were installed with pitch ratios (p/w) = 4, 6, 8,10, and 12. Experiments were carried out in the Reynolds number range of 4,000 to 20,000. The presence of the baffles facilitated turbulence within the duct, resulting in boosting both heat transfer and friction factor. The V-shaped baffles with the narrowest pitch ratio (p/w = 4) and a moderate twist ratio (y/w = 3), offered the best thermal performance factor which was as high as 2.02 meanwhile the baffles with p/w = 6, 8, 10, and 12 gave the maximum thermal performance factors of 1.99, 1.93, 1.85 and 1.82, respectively.

Influence of inline and staggered tube banks on heat transfer characteristics

2023-10-27T17:45:14+07:00

An investigation of the heat transfer characteristics of the staggered economizers with inline and staggered tube banks has been conducted. Experiments were performed at air flow rates of 489 kg/hr, 548 kg/hr, 602 kg/hr, 660 kg/hr, and 713 kg/hr, and water flow rates of 1,000 l/hr, 2,000 l/hr, 3,000 l/hr, and 4,000 l/hr. Experimental results revealed that a staggered heat exchanger with a 3-mm fin spacing (St = 53.7 mm, SD = 60.04 mm) yielded a maximum efficiency of 0.393.

A Numerical Investigation of Gain and Phase Errors of Unit Elements on Performance of Active Reconfigurable Intelligent Surface

2023-11-19T14:35:55+07:00

A reconfigurable intelligent surface, particularly the active type, is recognized as a promising candidate to expand the coverage of 5G/6G wireless communication and beyond, thanks to its inexpensive implementation as compared to conventional infrastructures. In this paper, the impact of implementation errors on the performance of the surface is investigated by virtue of numerical computation. The analysis equations for calculating the incident field on the surface, and the reflected field as well as the far field pattern from the surface are outlined. Numerical simulation including the gain and phase variations associated with each unit cell is given at different sizes and phase resolutions of the surface. The performance errors are quantified and subsequently employed as a guideline for designing a reconfigurable surface with robust performance in practice.

EFFECT OF ROTATING CONDITION ON HEAT TRANSFER CHARACTERISTICS OF IMPINGING JET ARRAY IN FLOW CHANNEL

2023-11-19T15:00:08+07:00

In this paper, heat transfer characteristics in the flow channel under stationary and rotating conditions were studied. The array of jets from 3 x 11 of orifice holes with diameter D_j = 5 mm with the inline arrangement was studied at pitch distance S/D_j = 4 and the impingement distance L/D_j = 2, 4 and 6. The jet flow was fixed with a Reynolds number of 10,000 and the rotation speed of the flow channel was varied between Ro = 0.0 - 0.0066 (or the speed of 400 rpm). The heat transfer was measured on the impingement surface using a Thermochromic Liquid Crystal (TLC) sheet to measure the temperature and calculate the convective heat transfer coefficient. Results showed that the rotational condition affected the heat transfer characteristics due to the effects of Centrifugal and Coriolis forces on the jet flow and cross flow. This caused the Nusselt number on the surface to be increase by 6.43 % for the case of leading side compared to that of the case of trailing side.

Development of DFTF algorithm for real-time processing

2023-12-03T19:00:57+07:00

This paper presents an advancement in the acceleration of object rotation direction detection through the implementation of a feature accumulation system derived from the Discriminant Feature Trace Transform (DFTF). DFTF data will be utilized in conjunction with machine learning to forecast the rotational direction of an object via the DFTF algorithm. It was discovered that in relation to the time required to obtain DFTF results, the procedure is intricate and involves multiple processing steps. As a result, the objective of the development guidelines that are outlined in this article is to accelerate the quest for solutions and streamline the work process. Adjusting the dimensions of the image data is the initial step in reducing the quantity of information that must be computed. Following this, the procedure for producing data in the trace transform domain was eradicated and substituted with machine learning in order to convert the image data to DFTF format. It is then incorporated into the standard procedure for calculating the rotation of an object. The outcomes of experiments conducted in this paper utilizing on Caltech-256 database. The suggested method allows for the measurement of data error using Mean Squared Error (MSE) and Root Mean Squared Error (RMSE), with data errors of 4.09 and 2.2, respectively. The optimal running speed per image in this experiment is 0.12 seconds, yielding an average accuracy of 98.7%.

Improvement of Soil Moisture Measurement using Non-inverting Amplifier on Embedded Board

2023-11-30T12:50:18+07:00

This paper presents the low cost soil moisture measurement using non-inverting amplifier in order to amplifier the small signal input that is the pre-processing part of embedded board. The non-inverting amplifier is applied for the small measured signal from soil to improve the input for embedded system. Arduino UNO board, Atmega328 microcontroller and the analog to digital converter (ADC) module are used to process the signal. Experiments show the proposed measurement in comparison with the 3-in-1 digital soil moisture meter and YY-1000 hand moisture meter outdoors. Empirical results show insignificantly compared with the commercial meters.

Colorimetric Responseto Acid-base of Polydiacetylene Prepared by Mixing Different Surfactant Molecules

2023-12-08T17:04:57+07:00

This paper presents a study investigate the color-switching behavior of polydiacetylenefabricated by mixing different surfactants on acid-base. The polydiacetylene solution is prepared from 10,12 pentacosadinoic acid monomer. The mixing of three type surfactants (Cetyltrimethyl ammonium bromide (CTAB), Sodium dodecyl sulfate (SDS) andTriton x-100) in various ratios in PCDA system may result different color transition property. We found that, The mixture of poly(PCDA:CTAB) (1:0.1) and ,poly(PCDA:SDS) (1:0.5 1:1 1:2 1:5) could be prepared blue phase upon UV-irradiation. The system of poly(PCDA:TritonX-100)with1:0.1 1:0.5 1:5 also exhibit blue phase. The pure poly(PCDA) show red phase at pH 9. The poly(PCDA:SDS) ratio1:2 also exhibit red phase at pH 9 which is the lowest pH comparing the orther mixture. In addition, the poly(PCDA) and poly(PCDA:SDS) ratio 1:2 were facricated on filter paper. The color transition of poly(PCDA) and pol(PCDA:SDS) reponse in pH as 11 and 10, pespectively. This work is basic knowledge to develop poly(PCDA) material to apply for sensing acid-base.