Journal of Science Ladkrabang

Achromatic Index of Unitary Addition Cayley Graph

Rungroj Wongkeao , Pakorn Poolsombut, Ngarmcherd Danpattanamongkon, Decha Samana — Fri, 27 Dec 2024 00:00:00 +0700

For a positive integer n >1, the unitary addition Cayley Graph G_n = Cay⁺ (Z_n ,U_n) is the graph whose vertex set is Z_n and if U_n = {a E Z_n : gcd(a,n) = 1} , Z_n the integers modulo n then two vertices a,b are adjacent if and only if a+b E U_n. In this research, we study about the unitary addition Cayley graphs, G_n = Cay⁺ (Z_n ,U_n), and to find the lower bound and upper bound of achromatic index of unitary addition Cayley graph where n is even and we improve the bound of achromatic index of graph G_n when n=2^k , k is the positive integer. Moreover, we found that the unitary addition Cayley graph G_nis the complete bipartite graph K_2^k-1_,2^k-1for n=2^k.

Rapid Aqueous Dye Adsorption Using Carbon Powder Derived from Agricultural Waste of Coconut in Bangtalad Sub-district, Chachoengsao Province

Pilaipon Nuthongkum, Prasopporn Junlabhut — Fri, 27 Dec 2024 00:00:00 +0700

This research emphasizes the significance of dye contaminants in industrial textile wastewater and their potential impact on health and the environment. The study aims to investigate the efficiency of low-cost carbon adsorbents derived from coconut waste through a single-step carbonization process for removing dye from aqueous solutions. The preparation of carbon powder from agriculture coconut waste, including coconut husk, young coconut shell and mature coconut shell, involves carbonization in a vertical furnace with a capacity of 200 L at a temperature of 600ºC for four hours. The characteristics of the carbon adsorbents derived from coconut waste were compared with commercially activated carbon powder. The crystalline structure was analyzed by X-ray Diffractometer (XRD), while the surface morphology and elemental composition were examined with a Scanning Electron Microscope (SEM) and Energy Dispersive Spectrometry (EDS). The results revealed that the carbon from coconut waste exhibited a carbon structure similar to commercial activated carbon. The surface morphology showed average surface pore size of 23.45±0.69, 4.72±0.17, 4.22±0.19, and N/A micrometers for coconut husk, young coconut shell, mature coconut shell and commercial activated carbon, respectively. Elemental analysis indicated that all the carbon materials mainly consisted of carbon and oxygen as the major components, with less than 2.84% impurities occurring in the carbonization process. The adsorption performance of methylene blue using carbon materials as adsorbents revealed that the suitable contact time was 15 minutes. The carbon waste from mature coconut shells and commercial activated carbon exhibited removal efficiencies of 94.78% and 97.38%, respectively. Despite a small difference in removal efficiency at 2.70%, indicating that the adsorption efficiency was similar to the commercial activated carbon. The pseudo-first-order reaction kinetics based on Lagergren's equation exhibited a similar value of 0.02968 min^-1, comparable to the commercial activated carbon's value of 0.03775 min^-1. However, efficient resource utilization focuses on the environmental, particularly in Chachoengsao Province. Additionally, efforts are being made to use low-cost waste materials from the community to be used as adsorbents for dye removal in wastewater treatment.

Comparison of Metaheuristic Methods for Solving Constrained Problems

Fri, 27 Dec 2024 00:00:00 +0700

Optimization algorithms and metaheuristic algorithms are effective techniques for solving unconstrained and constrained engineering problems. Metaheuristic algorithms are iterative search processes that efficiently explore the solution space. These methods effectively and efficiently search for solutions that are close to the optimal solution. The purpose of this research is to examine the efficiency of three algorithms: Flower Pollination Algorithm (FPA), Elevator Kinematic Optimization (EKO), and Rider Optimization Algorithm (ROA) in solving unconstrained and constrained problems. To compare the efficiency of these algorithms, we use the average, standard deviation, processing time, and signal-to-noise ratio. The experimental results demonstrate that ROA significantly outperforms the other two metaheuristic methods in terms of precision and quality of results, as well as requiring fewer searches to achieve the best solution. In this paper, the ROA can find better optimal solutions, but it gives higher standard deviation values. Additionally, ROA is easier to apply and does not require parameter tuning, while the FPA and EKO methods need parameter tuning for optimal performance.

Montmorillonite-Alginate Gel for Basic Red 51 Adsorption and Desorption

Duongdaw Pun-on, Papawarin Ruangrit, Saksit Chuenchomnakjad, Duangrat Thongkum — Fri, 27 Dec 2024 00:00:00 +0700

This research focused on the synthesis of the 6 formulas of sodium alginate gel bead mixed with montmorillonite clay mineral to be used for Basic red 51 dye adsorption. The influencing factors for the adsorption were studied such as the gel bead dosage, adsorption time, initial pH, and initial concentration of dye. The concentrations of residual dye in solution were followed up by UV-vis spectroscopy. The removal efficiency of formula 6 was 97.05%. The adsorption kinetic was best fitted to pseudo-second-order reaction and the adsorption isotherm confirmed Freundlich. Then Fourier transform infrared spectroscopy technique was used to characterize the functional group of formula 6 of sodium alginate gel bead modified with montmorillonite before and after adsorption. Moreover, the adsorption-desorption isotherms of N₂ gas were studied by Brunauer, Emmett and Teller technique, can be classified to type IV, indicates some degree of mesoporosity. From the desorption studies, it was found that the desorption of Basic red 51 dye from formula 3 gel beads was 36.75% using water and ethanol solution (70:30) and concentrated hydrochloric acid.

Clustering Information Exposure Behavior the Welfare State Needs Among Older Adults in Thailand

Arnisa Rasri, Wuttichai Choeichom, Paweesuda Chimpalee, Natcha Kunjiratanachot — Fri, 27 Dec 2024 00:00:00 +0700

This research has organized data on exposure to welfare state information among senior citizens in Thailand.The K-means algorithm was used to study the media consumption behavior of the seniors. Data derived from the Public Relations Policy and Planning Development Office of the Public Relations Department, covering the period from February 6, 2023 to February 24, 2023 and involving 1,314 participants. The optimal number of clusters was determined through the application of the Elbow method. The results of the clustering analysis, based on the survey of the elderly behavior, led to the identification of three and four distinct groups, respectively. Furthermore, the researchers used the analysis results to recommend publicizing welfare news for the older adults in Thailand, aiming to further enhance the efficiency of public relations.

Characteristics of Mozzarella Cheese Supplemented with Durian Pulp

Fri, 27 Dec 2024 00:00:00 +0700

The aims of this research were to: 1) study the optimal basic formula for mozzarella cheese, 2) study the optimal amount of durian pulp to be added to the selected basic mozzarella cheese, and 3) study the physical, chemical, and microbial properties of both the basic mozzarella cheese formula and the mozzarella cheese with added durian pulp. A consumer acceptance assessment of three variations of the basic mozzarella cheese formula showed that Form 2 received the highest scores from evaluators in terms of appearance, color, aroma, taste, texture, and overall liking, with average scores of 7.20, 7.70, 7.60, 7.80, 7.55, and 7.80, respectively. Durian pulp was subsequently added to the selected Form 2 mozzarella cheese at four different levels: 0% (control), 5%, 10%, and 15% of the weight of raw cow’s milk. Consumer acceptance evaluations revealed that mozzarella cheese with 10% durian pulp had the highest average scores for appearance, color, aroma, taste, texture, and overall liking, with scores of 8.00, 8.05, 7.95, 7.90, 8.03, and 8.23, respectively. An investigation of the physical characteristics of both the basic mozzarella cheese and the mozzarella cheese with 10% durian pulp revealed that the basic mozzarella cheese had lower brightness (L*) and stretchability but higher color intensity in terms of redness (a*) and yellowness (b*) than the mozzarella cheese with 10% durian pulp. In terms of chemical quality, the mozzarella cheese with 10% durian pulp had slightly lower energy content, protein, fat, and ash values, but higher carbohydrate and moisture content compared to the basic mozzarella cheese. Regarding microbiological quality, both formulations had microbial amounts in accordance with the specified standards. According to the Ministry of Public Health’s standards, set by Notification of the Ministry of Public Health (No.209) B.E.2543 (2000) Re: Prescribing the quality or standard, principles, conditions and methods of analysis for pathogenic microorganisms in foods.

Comparison of Precision Coefficients for Streamflow Data Simulation

Noparat Techapunratanakul, Pongpan Kanjanakaroon, Chaiwat Ekkawatpanit — Fri, 27 Dec 2024 00:00:00 +0700

Streamflow data is crucial for water resource development projects. Acquiring long-term streamflow data poses difficulties due to maintenance or technological issues. The use of a mathematical model may reconstruct missing streamflow data. Nevertheless, it is necessary to calibrate and validate simulation data using precision coefficients. Different precision coefficients can be used to evaluate the results of hydrological simulations. This paper presents the suitability and constraints of precision coefficients in evaluating streamflow outcomes using a hydrological model under three conditions: water balance, flood, and drought. The simulated data was generated with both systematic and dynamic errors. Twenty-one coefficients were selected based on the principle of relative and absolute errors to evaluate the simulated data. Regardless of systematic errors, the findings indicate that all simulated outcome conditions could be evaluated using several coefficients such as NSE, NSE_j₌₁, NSE_j₌₃, NSE_rQ, ln NSE, NSE_sqrtQ, NSE_iQ, MSE, RMSE, MAE, RMSRE, and AAPE. These coefficients could analyze the simulation’s accuracy as well as determine its accuracy tendency. In addition, the precision coefficient RLFD_oH can be used to evaluate the simulation results for flood scenarios, and the precision coefficients NSE_uL, B_uL, and RLFD_uL can be used to assess the simulations for drought scenarios. For dynamic errors, the coefficients of NSE_j₌₁, NSE_iQ, and RMSRE were suitable for assessing the water balance and flood conditions, while drought is aligned with the coefficients of NSE_uL and RLFD_uL. The results can serve as a criterion for determining appropriate coefficients for streamflow simulation.

A Comparison of the Imputation Methods for Balanced Transportation Problems

Unna Kongkoy , Kanlaya Boonlha — Fri, 27 Dec 2024 00:00:00 +0700

Transportation model is a special case of linear programming to transport a product from sources to destinations at total minimum cost. The objective of this study is comparing the efficiency of estimating when the variable costs are missing completely at random in balanced transportation problems by imputation 4 methods which are mean, median, maximum, and minimum. The cost for transport model is set to a uniform distribution and a normal distribution with coefficients of variation to 5%, 10%, 15%, 20%, 25%, and 30%. The Monte Carlo simulation was repeated 1,000 times. Set the number of sources and destinations to be equal in size 4, 5, 7, 10, and 20. The percentage of missing data are 5%, 10%, 15% and 20% of the sample size. The criterion used for comparison is the Root Mean Square Error (RMSE). The results found that as the number of sources and destinations increases, RMSE also increases across all imputation methods. Among the methods, imputation using the mean resulted in the lowest RMSE, followed by the median, maximum, and minimum, respectively.

Floating Photocatalyst based on Titanium Dioxide Immobilized on Carboxymethyl Cellulose Hydrogel from Bagasse

Prachya Watasit, Wongduan Maison , wiyarat kumutanat — Fri, 27 Dec 2024 00:00:00 +0700

This research focused on the preparation of Titanium dioxide Carboxymethyl Cellulose Hydrogel (TiO₂/CMC-hydrogel) floating catalyst for removing methyl orange dye. The obtained Carboxymethyl Cellulose (CMC) from bagasse was mixed with nano Titanium dioxide and then crosslinked the polymer into hydrogel using succinic acid. The synthesized hydrogel films were characterized by Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR-FTIR) technique. Surface morphology of hydrogels was analyzed by Field Emission Scanning Electron Microscope (FE-SEM). Band gap energy was evaluated by Ultraviolet–Visible Diffuse Reflectance Spectroscopy (UV–Vis DRS) technique. The study of morphology showed that TiO₂ particles can disperse in CMC-hydrogel. Infrared absorption of carboxylate groups was shifted when adding TiO₂content. This can be suggested that there are interactions between carboxylate of CMC and TiO₂ particles. In addition, CMC-hydrogel can decrease the band gap energy of TiO₂, leading to improving methyl orange removal under sunlight. 2%TiO₂/CMC-hydrogel floating catalyst provided an efficiency to remove methyl orange dye up to 78.11% after testing for 70 hours.

Factors Analysis of Unified Theory of Acceptance and Use of Technology Version 2: Influence on the Regulation of Acceptance and Use of Vending Machines

Apinya Ingard, Supot Ingard — Fri, 27 Dec 2024 00:00:00 +0700

The aims of research were 1) to develop a measure of acceptance and use of vending machines to meet the standard criteria, 2) to study the influence of acceptance on vending machines usage, and 3) to study the influence of moderator variables affecting acceptance on vending machines usage: gender, age, and experience. The study was conducted on 406 subjects who had used vending machines no less than twice in the past month, which serving the Bangkok and vicinity areas and derived by quota sampling method. A questionnaire was assessed for content validity index, both Item and Scale level method, and reliability by the Cronbach Alpha coefficient. Data were analyzed statistically, namely Mahalanobis d-Square, comparison of the average variance extracted with the shared variance, structural equation modeling, and multi-group analysis. The results reviewed that 1) the measurement instrument was met with the Unified Theory of Acceptance and Use of Technology; version 2 and passed the criteria for assessing validity. 2) Factors directly influencing behavior intention with statistical significance include effort expectancy, social influence, hedonic motivation, price value, and habit. Moreover, the factors directly influencing the use behavior were statistically significant, namely, habit and behavior intention, and 3) gender, and age were the variable moderate influence for 2 routes, and experience was the variable moderate influencing for 3 paths.