Journal of Engineering and Innovation

Experimental study of post-processing for key generation in entangled free-space quantum key distribution system

Patcharapong Treeviriyanupab — 2024-06-01

This paper presents the design and development of practical post-processing software for a general quantum key distribution system. The proposed algorithms consist of three main contributions: 1) channel parameter estimation for quantum bit error rates by a random key sampling method, 2) information reconciliation using rate-adaptive LDPC codes, that collaborate with identical key confirmation by employing a polynomial-based hash function, and 3) privacy amplification performed by a universal hash function, where the binary information is randomly chosen to construct the Toeplitz matrix corresponding to the condition of a secure secret key rate. The proposed post-processing algorithms were implemented and tested in an entangled quantum key distribution experiment based on the BBM92 protocol over a 11-meter free-space quantum channel link. The experiment was conducted over 100 cycles and was able to generate the average sifted key rate of 1,109.08 bits per second. The efficiency of the proposed algorithms enabled two legitimate parties to generate the identical secret key according to the information-theoretic security principles, where the average estimated quantum bit error rate was 2.0127%, the average efficiency of information reconciliation was 1.1919, and the average final secret key rate was 428.42 bits per second. The proposed algorithms could be used in the industrial quantum key distribution systems based on a discrete-variable protocol by optimizing the input parameters of the post-processing procedure, especially for high-speed applications.

Unconfined compressive strength development in recycled pavement base material improved by fly ash and calcium carbide residue geopolymer

Sermsak Tiyasangthong — 2024-06-01

This research investigates unconfined compressive strength development in recycled pavement base material improved by fly ash and calcium carbide residue geopolymer at curing times of 7, 14, 28, 60, and 90 days. This research studied the effect of liquid alkaline activator content comprised of sodium silicate (NS) and sodium hydroxide (NH) with NH concentration of 8 molars, the RCR:CCR:FA ratios, and the NS:NH ratios. The test result showed that the maximum dry unit weight of the RCR-CCR-FA geopolymer sample decreased as the FA increased due to the lower specific gravity of FA. The 7-day unconfined compressive strength increased as FA content increased due to the increased amount of Si and Al. Sample with optimum liquid alkaline content, RCR:CCR:FA ratio of 40:10:50 and NS:NH ratio of 2 gave the maximum unconfined compressive strength of 9.88 MPa. Based on the Department of Highways (DOH) standard, All ingredients passed the DOH standard. Furthermore, the proposed equation is beneficial for estimating the unconfined compressive strength of RCR-CCR-FA geopolymer when 28-day unconfined compressive strength was known.

Evaluation of thermal conductivity and compressive strength of cellular lightweight concrete with various heating temperatures

Thnabhorn Thaveevouthti — 2024-06-01

Cellular lightweight concrete is mortar mixed with preserved air bubbles or foam liquid distributed in concrete instead of coarse aggregate in order to reduce the concrete unit weight. The properties of cellular lightweight concrete vary with unit weights. Concrete with great amount of bubbles given high porous and light weight provides low thermal conductivity. Cellular lightweight concrete with unit weights of 1600 and 1800 kilograms per cubic meter using water to cement ratio of 0.45 and 0.55 and sand to cement ratio of 2:1 and 3:1 were designed and produced for the study of thermal conductivity and the remained compressive strength after heating at various temperatures. The results are as follows: (1) the thermal conductivity coefficient ranged from 0.164 to 0.255 watts per meter Kelvin and (2) the average remained compressive strength after heating at temperature of 200, 400, 600, 800 and 1000 degrees are approximately 91, 76, 52, 28 and 17 percent, respectively.

The hot compression of bamboo plate from bamboo waste to utilization

Worapong Boonchouytan — 2024-06-01

This research aimed to study a suitable condition for producing bamboo sheets from bamboo scraps. The size of bamboo scraps was 3 centimeters and the moisture content did not exceed 13%. The solder is made from natural materials. There were 3 levels of temperature for a hot compress, i.e. 170, 190 and 210 degrees Celsius and there were 3 levels of extrusion time, namely, 10, 15 and 20 minutes. Physical and mechanical properties were tested, which include thickness swelling, bending test, bond strength of bolts, and tensile test, to compare to Thai industrial standard for flat pressed (FP) particleboard TIS. 876-2547). The study results revealed that the suitable condition for bamboo sheet hot extrusion from bamboo scraps was at the hot compress temperature of 190 degrees Celsius for 15 minutes, due to its highest average bending, highest average modulus of bending, highest average bending strain, highest average tensile strength and modulus of tensile. The comparison result to Thai industrial standard (TIS. 876-2547) found they passed 3 standards of average thickness swelling, tensile strength and modulus of tensile and did not pass 2 standards of bending and modulus of bending. In addition, the satisfaction test score of bamboo sheet hot extrusion from bamboo scraps was 3.41, at a high level.

Harmonic detection using PQF with fundamental positive sequence voltage detector for co-phase AC electric railway systems

Twin Udomkitpanya — 2024-06-01

This paper presents the harmonic detection using PQF in combination with the fundamental positive sequence voltage detector (Fundamental Positive Sequence Voltage Detector : FPSVD) for co-phase AC railway systems. The proposed method is used to calculate the reference current for harmonic compensation of the shunt active power filter (Shunt Active Power Filter : SAPF), both in cases where the voltage source of the railway system is a pure sinusoidal waveform and in cases where the voltage source of the railway system is distorted due to harmonics. Harmonic detection tests in co-phase AC railway systems apply hardware in the loop simulation techniques using Simulink/MATLAB software with the TMS320C2000^TM Experimenter Kit DSP board. The simulation results for the case where the voltage source of the railway systems is a pure sinusoidal waveform found that harmonic detection using the PQF method can calculate the reference current more accurately and flexibly than the conventional PQ method. As a result, the percentage of total harmonic distortion (%THD) after compensation at the three-phase power system, which is the Point of Common Coupling (PCC) is less than 0.42%. In cases where the voltage supply of the railway systems is distorted. It was found that harmonic detection by the PQF method combined with the FPSVD method has better performance than using only the PQF method, resulting in the shunt active power filter effectively removing harmonics in co-phase AC railway systems, and %THD after compensation at the PCC point is less than 0.86%. Moreover, the %THD after compensation of the source current decreases within the framework of IEEE Standard 519-2014.

A method for estimating dirt on photovoltaic panel using TCS3200 color sensor module

Anucha Deephang — 2024-06-01

This paper presents the application of the TCS3200 color sensor module with Arduino ESP32 microcontroller to estimate the dirtiness of solar panels caused by dust. The surfaces of solar panels with different amounts of dust accumulation have different reflectance values. Therefore, this reflectance measurement instrument was designed using the TCS3200 color sensor module to measure the reflectivity in RGB values and convert it to gray scale values. The gray scale was then used to correlate with the amount of dust accumulated on the solar panels by experiments by simulating the dust situation on the solar panels at various levels ranging from 0 – 25 g/m² on a 50 W polycrystalline solar panels. The results showed that the gray scale value measured by the TCS3200 color sensor module correlated with the amount of dust on the solar panel. When tested by measuring the short-circuit current and open-circuit voltage of the tested solar panel. It was found that the value decreased with the amount of dust on the solar panel inversely related to the gray scale. The maximum power output from the solar panel is 43.56 W when the solar panel is clean and free of dust. When the dust accumulation on a solar panel reaches 5 g or more, it initiates a decline in the power output generated by the panel. The power output reached its minimum value at 38.23 W when the dust accumulation on the solar panel reached 25 g/m². The decrease in power is caused by the amount of sunlight reaching the solar panel is reduced because it is blocked by dust particles, causing the solar panel to lose its efficiency in receiving sunlight. The soil ratio of solar panels decreased inversely with the amount of dust. It was found that the soil ratio of the solar panels decreased inversely with the amount of dust. it can be inferred that the TCS3200 color sensor module is capable of measuring the difference in reflectivity caused by dust on the surface of the solar panel. This ability enables the module to estimate the level of dirtiness or dust accumulation on the solar panel surface. Therefore, the TCS3200 color sensor module can be used as a tool to assess the cleanliness of the solar panel surface based on its reflectivity readings.

A Development of semi-automated production systems for precast concrete factories

Vacharapoom Benjaoran — 2024-06-01

Precast concrete component production is an important part of off-site construction technology. The main construction activities are substantially moved to the factory so that the production process and the environment can be managed to achieve higher efficiency. The design of the production process needs to consider all constraints related to the size and shape of the factory site. This research was conducted to determine the location of the factory on the land of a participating private company. The layout and the production process were designed in accordance with the area, which resulted in a factory that was divided into 4 lanes, 9 rows per lane, including the design of new machines to help achieve semi-automatic production with lower investment than the commercialized technology from abroad. As a result, there are 2 production methods, namely Multi-lane Circulatory Pallet (MLCP), and Single-line Circulatory Pallet (SLCP), then the advantages and disadvantages of each method are analyzed. Finally, it is an estimation of the investment and cost-effectiveness analysis of the establishment of this new factory. In five years, the factory is expected to yield a net present value (NPV) of 3.9 million baht, with an attractive internal rate of return (IRR) at 8.4%, and a payback period (PB) of 4 years and 2 months. The results of the new factory design indicate that the precast concrete production business can be initiated at a lower investment cost and suitable for the potential of medium-sized construction companies.

Failure analysis of piezoelectric actuators in a hard disk drive head stack assembly

Suwitcha Titaram — 2024-06-01

The most common problem in the assembly of the read/write heads in hard disk drives is the damage of the piezoelectric actuator, which is rigid but brittle and prone to fracture. The objective of this research is to predict the behavior under impact conditions of the head stack assembly (HSA) model with the piezoelectric actuator installed. The authors found that the piezoelectric actuator is damaged during installation to the support device. The finite element model of the read/write head is made using the properties of stainless steel and piezoelectric (PZT) materials, and the force on the HSA is converted to impact velocities in the range of 8.4 - 9.2 m/s. The model is then analyzed using explicit dynamics in the condition that the HSA collides with a rigid support. The HSA can move freely in vertical direction (Z axis) but cannot move in the plane (X, Y axes). After the analysis, the deformation and Von Mises stress results are investigated. The FEA results show reasonable deflection behavior of the read/write head and show that the maximum Von Mises stress in the piezoelectric actuator is due to impact. The maximum stress occurs before the read/write head reaches its maximum deflection, suggesting that explicit dynamics analysis is preferred to static analysis. The impact velocity is a factor that influences the stress results, as can be observed from the maximum Von Mises stress in the piezoelectric actuator, which ranges from 135.74 to 154.61 MPa. The stress values increase with higher impact velocities. However, the analysis predicts that the piezoelectric actuator is damaged at all impact velocities, which does not align with the actual test results. Additionally, the predicted deformation of the piezoelectric actuator is much greater than the deformation observed in actual tests. The authors believe that these analysis results can be improved by using more accurate properties and failure model parameters of the piezoelectric material in the construction of the finite element model. The material information can be obtained from appropriate mechanical tests. The results from this study can be used as a guideline for improving the assembly process to reduce the number of piezoelectric actuator damage.

Application of lean techniques to operation improvement in tobacco leaf production process

Methawin Samsri — 2024-06-02

The purpose of this research was to reduce process waste and to compare the performance before and after the improvement. By lean techniques, work study, 7 waste and ECRS techniques to analyze data of Ban Kaen Sai Tobacco Producer Enterprise Group, Rop Mueang Sub-district, Mueang District, Roi Et Province. From collecting data and analyzing the results of the work before improvement, it was found that there were 5 main work processes cultivation, harvesting, stringing of tobacco leaves, drying tobacco leaves and compression tobacco leaves. From the study of the work process data, 3 steps were selected: tobacco leaf stringing; drying and compression to improve work processes and reduce waste occurring in the process. From analyzing data and improving work processes. Work process before improvement It was found that there were 23 working steps and after It was found that 16 work steps can reduce work steps by 7 steps and work time before improvement 441.6 hours, after improvement 321.12 hours, can reduce work time by 120.5 hours and the working distance before improvement was 1,220 meter and after improvement was 660 meters. The working distance could be reduce to 560 meters after improvement and development of new work processes, 100% of the tobacco production work process.

The factor of construction labor management affected by the COVID-19 crisisin Thailand

Wuttipong Kusonkhum — 2024-06-02

During the COVID-19 epidemic, it greatly affected the construction industry, Especially the management of construction workers, because this virus is easily spread from person to person. Therefore, this study aims to study factors in labor management in construction projects affected by the spread of the COVID-19 virus and suggest solutions from literature reviews. From the collection of questionnaires with a reliability equal to 0.95 and from the quality inspection of the tools. According to the development, there are 10 suitable factors for collecting data and collecting questionnaires from a sample group of stakeholders in the construction industry in Khon Kaen Province, including construction contractors, consultants, and others. of 384 sets, received 443 sets of responses, and analyzed the factor groups by elemental analysis technique. From the results, the components of all 10 factors can be categorized by the factor analysis method into 4 groups as follows: namely health welfare, human and resource management, project management, and contract management. There are eigenvalues of 2.179, 1.212, 1.135 and 1.014 respectively.

Maximum power point tracking of stand-alone photovoltaic system using fuzzy logic based on P&O method

Athit Rungjaroen — 2024-06-02

This paper presents a maximum power point tracking (MPPT) for stand-alone photovoltaic (PV) system. The considered system consists of a PV panel connected to a buck converter and a battery used as energy storage. The MPPT commonly used perturb and observe (P&O) method because the control is simple. The efficiency of the P&O MPPT method depends on the appropriate step size of control signal. The duty cycle rate of change () was used as a step size of control signal. Fuzzy logic control (FLC) can be used for non-linear tasks, resulting in a wide variety of applications. In this paper, FLC is used to determine the to optimize to increase the control efficiency. The proposed MPPT method performance is proven by using MATLAB/Simulink, Laboratory prototype and 2.4kW prototype applied to water distribution control house of the university farm, Suranaree University of Technology. The simulation and experimental results demonstrate the effectiveness of the proposed MPPT method. The proposed algorithm can provide the faster maximum power convergence and can reduce steady-state power fluctuations better than those of P&O method.

First order confirmatory factor analysis of factors affecting labor productivity in the construction

Tewakun Chankampom — 2024-06-02

โดยทั่วไปผลิตภาพในการก่อสร้างมักจะแสดงผลิตภาพแรงงาน แต่อัตราการเติบโตของผลิตภาพ (Productivity) อุตสาหกรรมก่อสร้างทั่วโลกค่อนข้างต่ำเมื่อเปรียบเทียบกับอุตสาหกรรมอื่น ซึ่งในช่วงเกือบ 10 ปีที่ผ่านมาผลิตภาพแรงงานไทยอยู่ในระดับค่อนข้างต่ำและมีแนวโน้มลดลง สะท้อนว่าไทยมุ่งเน้นปัจจัยเงินทุนและแรงงานมากกว่าการพัฒนาคุณภาพแรงงาน ดังนั้น การมีแรงงานที่มีผลิตภาพสูงในแต่ละขั้นตอนของงานมีบทบาทสำคัญในความสำเร็จของโครงการ การวิจัยนี้จึงมีวัตถุประสงค์เพื่อตรวจสอบความกลมกลืนของโมเดลองค์ประกอบยืนยันลำดับที่หนึ่งที่มีนัยต่อผลิตภาพแรงงานในอุตสาหกรรมก่อสร้าง ซึ่งใช้แบบสอบถามในการเก็บรวบรวมข้อมูล กลุ่มตัวอย่างคือแรงงานในโครงการก่อสร้างบ้านพักอาศัย พื้นที่กรุงเทพมหานครและปริมณฑล จำนวน 336 คน วิเคราะห์ข้อมูลด้วยเทคนิคทางสถิติการวิเคราะห์ข้อมูลเชิงยืนยัน (Confirmatory Factor Analysis: CFA) ผลการวิจัยพบว่า ปัจจัยที่มีนัยต่อผลิตภาพแรงงานมีห้าองค์ประกอบ คือ วัสดุ อุปกรณ์/เครื่องมือ การวางแผน ทำงานซ้ำ และสภาพอากาศ โดยองค์ประกอบหลักมีความกลมกลืนกับข้อมูลเชิงประจักษ์ พิจารณาจากดัชนีความสอดคล้อง คือ Relative Chi-Square = 1.146 df = 104 P-value = 0.146 NFI = 0.978 GFI = 0.969 CFI = 0.997 RMR = 0.043 และ RMSEA = 0.021 ปัจจัยหลักมีค่าสัมประสิทธิ์สหสัมพันธ์อยู่ระหว่าง 0.273 - 0.947 ส่วนปัจจัยย่อยมีน้ำหนักความถดถอยในรูปมาตรฐานระหว่าง 0.507 - 0.968

Study of temperature to moisture ratio change and color during drying Turmeric with hot air

Marina Mani — 2024-06-02

The purpose of this research was to study the effect of temperature on the change in moisture ratio of Turmeric under drying conditions at 50, 60 and 70 °C. and a hot air speed of 1.5 m/s. Drying was performed from the initial moisture content of 1,060.61 ± 1.45 percent dry basis until the remaining moisture was 136.40 ± 2.35 percent dry basis. Then, the change in moisture ratio during drying was studied with a mathematical model of Lewis, Henderson and Pabis, Page, Modified Page I, Logistic, Logarithmic, Two term and Midilli et al. found that the Logarithmic model best predicted the moisture ratio change characteristics of Turmeric. It has the highest coefficient of determination (R²) and chi-square () , root mean square error (RMSE) and the lowest mean biased error (MBE). The effective moisture diffusivity coefficient of Turmeric drying was between 5.58 x 10^-8 - 2.39 x 10^-7 square meters per second. From the CIE (L*-a*-b*) color quality change analysis of Turmeric, it was found that the color parameters L* (brightness), a* (red/green value) and b* (yellow, blue value) were used to estimate the color change during drying. The L*, a* and b* values of dehydrated Turmeric were decreased when the drying temperature is higher while the total color difference (TCD) was 20.032, 18.231 and 15.476 at the temperature of 50, 60 and 70 °C.

Properties of recycled polypropylene has undergone an additive process to produce plastic filament for 3D printers

Phatthawit Siripaiboonsub — 2024-06-02

This research was performed to compare the mechanical and physical properties of polylactic acid plastic strands with fluorescent agent additives with recycled polypropylene plastic strands mixed with polylactid acid, and fluorescent additives for 3D molding process. Three proportions of fluorescent agent additives were used: 0.3%, 0.5% and 1%. The results showed that the tensile strength, modulus of elasticity, percentage of elongation, hardness, flow index, of recycled polypropylene strands mixed with polylactid acid and 0.3% fluorescence agent ratio were optimal, resulting in favorable plastic filaments for 3D printer molding. The addition of large quantities of fluorescent agent resulted in polymer viscosity, which decreased the tensile strength and the flow index of the product. Modulus of elasticity, hardness and elongation percentage were found to have tear characteristics in the tensile test specimen, demonstrating the density characteristics of the molding layer, which corresponded to the elongation percentage. The luster results of all 4 types of plastic strands indicated an excitation wavelength in the 509 nm range, which increased with an increase in the amount of fluorescent agent as a result, the plastic line was shinier. However, the luminosity curves of 0.3%, 0.5% and 1% filling proportions showed that the luminescence proportions were brighter but not significantly different.