Srinakharinwirot University Journal of Sciences and Technology

COMPARISONS OF THE PURCHASING AND PRODUCTION LOT SIZING METHODS

2023-11-03T12:35:53+07:00

The objective of this research is to determine optimal purchase and production lot size of each product that meets demand at minimum total cost of purchase and production including purchase costs, set up costs, production costs, and holding costs, and to compare results of total production cost and solving time between the methods of a dynamic lot-sizing production and purchase model and dynamic lot sizing model purchase and production combination of the whole production line. Comparing the results between the two methods shows that the total cost and the solving time of the dynamic lot sizing model production and purchase combination of the whole production line is less than the other method.

SiO2-TiO2 NANOCOMPOSITE WITH SILICA FROM THE RICE HUSK FOR DECOMPOSITION OF METHYLENE BLUE

2023-11-03T12:38:38+07:00

The study of SiO₂-TiO₂ nanocomposite (SiO₂-TiO₂) with silica from the rice husk was intended to be enhanced the photocatalytic of titanium dioxide (TiO₂) for decomposition of methylene blue. The morphology of the hybrid was characterized by XRD, FT-IR and SEM. The photocatalytic activity was study by using the degradation of methylene blue with spectrophotometry technique. From the study found that, Silica (SiO₂) can be extracted from the rice husk at 6.62%. After prepared to SiO₂-TiO₂ composite, the hybrid presented the spherical particles at diameter of about 0.5 μm. The SiO₂-TiO₂ nanocomposite showed the photocatalytic activity at 91.65 % in sunlight at 660 min, while the pure titanium dioxide revealed the photocatalytic activity at 48.45 % in sunlight at the same time. The photocatalytic activity of SiO₂-TiO₂ nanocomposites was higher than pure titanium dioxide (TiO₂). Indicating that the mesoporous silica (SiO₂) can be improved the photocatalytic efficiency of titanium dioxide. It is related to the structure and particle sizes of the titanium dioxide (TiO₂) as well as adsorption of methylene blue of silica (SiO₂) were resulting photocatalytic activity in better.
The prepared nanocomposite material was effective in degrading the color of methylene blue under sunlight.

SEASONAL VARIATION OF TRACE ELEMENT IN SUSPENDED PARTICLE AT SAKAERAT BIOSPHERE RESERVE FOREST, NAKHON RATCHASIMA PROVINCE

2023-11-03T12:40:34+07:00

This research focused on atmospheric trace elements contamination in particulate matter (PM) at rural area, which a major cause of health ecosystem and environmental impacts. The research aimed to study the relationship between dust particles and environmental factors, examine the annual variation in particulate matter as PM2.5 and PM10 and investigate for heavy metals concentrations at dry dipterocarp forest, Sakaerat Environmental Research Station (SERS), Nakhon Ratchasima province, Thailand. The trace element for 5 heavy metals consist of selenium (Se), arsenic (As), iron (Fe), cadmium (Cd), and lead (Pb). The air sampling was collected by 2 stage filter pack at 5 meter above the ground for 5 days per month, from January to December 2019. The results demonstrated that the yearly average concentrations of PM2.5 and PM10 were 23.00±17.11 and 8.17±5.52 µg/m³. The contamination of PM2.5 between wet and dry seasons were significant different (p-value < 0.05) and the maximum value of PM2.5 was 59.72 µg/m³ in March. While, the heavy metals in fine particulate matters were not significant different with seasonal variation (p-value < 0.05). Thus, the average concentration of heavy metals was Se > As > Fe > Cd > Pb as 0.79±0.39, 0.48±0.21, 0.31±0.18, 0.23±0.13, and 0.14±0.22 µg/m³ – which account for 41%, 24%, 16%, 12%, and 7%, respectively. In this study, Se, As and Pb were maximum contaminated in fine particulate matter in May as 1.62, 0.96 and 0.79 µg/m³, respectively.

IMPROVEMENT GRINDING PROCESS OF ROLLER MONOBLOC MODEL MPS 280

2023-11-03T12:43:11+07:00

A new operation process to increase the grinding efficiency of the metal casting product “Roller Monobloc MPS 280” by using the Motion/Time Study. The sample data selected for the study comes from the use of Roller Monobloc MPS 280 for 3 times by changing the method and position of grinding from 3 step riser, ingate and curve riser to 4 step, focusing on curve riser which is split to 2 steps gridding: gridding in angle position and gridding at side riser position. The result of this study was a decrease in the grinding process time from 7552 minute to 7183 minute 4.89 percent.

THE DEVELOPMENT OF PECTIN EXTRACTION PROCEDURE FROM WATERMELON PEEL USING ORGANIC ACID FOR FOOD INDUSTRY

2023-11-03T12:44:51+07:00

This research aims to study the extraction of pectin from watermelon peels using organic acid. The effects of various parameters on extraction, such as citric acid concentration (0.025 0.05 0.1 0.25 molar), weight and volume of watermelon peels and solvent (1:12 1:16 1:20 1:24 gram per milliter) temperature (75 85 95 degree Celsius) and extraction time (30 60 90 120 minute) were investigated. According to the results, the optimum conditions were 0.025 mole per liter of citric acid solution, a solid-liquid ratio of 1:12 grams per milliliters, 95°C, and 60 minutes of extraction time. The extracted watermelon pectin was precipitated by ethanol 95 %v/v. The characteristics of watermelon peels pectin were analyzed. It was shown that the production yield, galacturonic acid, methoxyl contents and degree of esterification were 13.21, 68.03, 6.86, and 62.18 % respectively. From the results, pectin from watermelon peel was classified as having a high methoxyl content. The chemical structure of watermelon peels pectin and apple commercial pectin were determined by Fourier transform infrared spectrometer (FT-IR). The functional groups of pectin from watermelon peels were similar to those of commercial pectin from apple. Thermogravimetric analysis technique (TGA) was used to determine the thermal property of pectin from watermelon peels. The maximum thermal decomposition temperature (DTG_max) of pectin from watermelon was 255 °C, indicating high thermal stability. The results revealed that watermelon peels pectin can be an inexpensive source to obtain good pectin quality. Pectin from watermelon peels would have a high potential to be used as food additive in food industry and high temperature processed foods.

CHANGES OF WATER QUALITY IN MUDDY BEACHES DUE TO THE INFLUENCE OF EFFLUENT FROM THE COMMUNITY WASTEWATER TREATMENT SYSTEM, THE ROYAL INITIAL ENVIRONMENT RESEARCH AND DEVELOPMENT LAEM PHAK BIA PROJECT

2023-11-03T12:46:54+07:00

This research aims to study the change in water quality in muddy beaches affected by effluents from the wastewater treatment system of The Royal Initial Environment Research and Development Laem Phak Bia Project, Phetchaburi Province. Determine the sampling station in the muddy beaches in front of the mangrove forest by surveying 3 lines perpendicular to the coast, consisting of line R as a reference area that does not influence the community wastewater treatment system, lines A and B are received effluent from the community wastewater treatment system., each line has 5 sampling stations. Water samples were collected during the low tide of the highest tide days in October 2019 (rainy season) and February 2020 (dry season). The results showed that the water quality of both seasons was in the Seawater quality standards for aquaculture, when comparing the water quality along with the survey, it was found that TKN, ammonia, and TP in the R line were higher than the A and B line, at 4.7±1.6, 0.019±0.003 and 0.15±0.03 mg/L, respectively, due to household water activities that discharged water into a small canal flowing through the community into the mangrove forest in the R line, unlike the A and B line, which receives effluent from treatment system that is diluted with effluent and is absorbed by mangrove vegetation before it enters the mangrove forest. When comparing seawater quality parallel to that of the coast, there was no significant difference (P < 0.05), and when comparing the water quality in both seasons, it was found that temperature, salinity, EC, TDS, DO, TKN, ammonia, and TP were significantly different (P < 0.05) with salinity, EC, TDS, TKN, ammonia, and TP in the season. The dry season is more valuable than the rainy season, the temperature and DO content in the dry season were lower than in the rainy season due to the effects of seawater and the impact of suspended solids and nutrients from nearby canals, including organic and inorganic substances from the decomposition of living organisms in mangrove forests.

STOCK PRICE FORECAST MODEL OF THE SIAM CEMENT PUBLIC COMPANY LIMITED

2023-11-03T12:57:11+07:00

The objective of this study is to construct an appropriate forecasting model for the stock price time series of Siam Cement Public Company Limited. The monthly average latest prices, which were gathered via http://th.investing.com from January 1995 to December 2021 (324 months) were divided into 2 datasets. The first dataset from January 1995 to December 2020 (312 months) for constructing the forecasting models via the use of statistical methods, as well as, (1) Holt’s exponential smoothing method, (2) Brown’s exponential smoothing method, (3) damped trend exponential smoothing method, and (4) Box-Jenkins method. The second dataset from January to December 2021 (12 months) was used to compare the accuracy of the forecast models via the lowest mean absolute percentage error and root mean squared error. The results indicated that the most accurate method was Holt’s exponential smoothing method, followed by the damped trend exponential smoothing method. However, the forecast values of both methods were reliable because the average forecast values were not significantly different at the 0.05 level.

FACTORS ASSOCIATED WITH OBESITY AND ABDOMINAL OBESITY AMONG INHABITANTS IN ONGKHARAK SUBDISTRICT, ONGKHARAK DISTRICT, NAKHONNAYOK PROVINCE

2023-11-03T13:00:04+07:00

Obesity and abdominal obesity are predominant risk factors for the development of non-communicable diseases (NCDs) which are public health concern and also socioeconomic problems in Thailand and worldwide. This survey study aimed to assess the prevalence and associated factors of obesity and abdominal obesity among inhabitants in Ongkharak subdistrict, Ongkharak district, Nakhonnayok province in 356 participants. Data were collected by using questionnaires including general data, individual behaviors, and stress levels. Obesity and abdominal obesity were evaluated by the body mass index (BMI) and waist circumference, respectively. The results showed that most participants were female (57.87%) and mild stress level (45.79%). The average age, BMI and waist circumference were 38.94 years, 24.69 kilograms per square meters and 85.48 centimeters, respectively. The prevalence of obesity and abdominal obesity were 42.98% and 50.28%, respectively. Factors significantly associated obesity were occupation, income, hypertension and dyslipidemia. Factors significantly related abdominal obesity were gender, age, marital status, hypertension and dyslipidemia. These lead to the development of educating guidelines for individuals to take care of themselves. The properly change in their behavior and lifestyle, especially controlling of blood pressure and blood lipid may improve obesity, abdominal obesity and consequential NCDs.

DEVELOPMENT OF WATER TEMPERATURE CONTROL SYSTEM FOR TEMPERATURE CONTROLLED MATTRESS

2023-11-03T13:01:49+07:00

This study aims to develop a water temperature control system for developing of temperature control mattress. In this step of study was designed a water temperature control system to get temperature control mattress prototype, that useful for quality of sleep in aging. The experiment in this study had examined the thermoregulation ability of the thermoelectric modules (peltier) for water temperature control. The 2 types of peltier were (1) TEC12706 and (2) TEC12712, which consisted of 4 scenarios. Scenario 1: experiment to study suitable peltier types for this application. Scenario 2: experiment to study the stored energy in water and peltier. Scenario 3: experiment to study the cooling ability of the developed system to the mattress. Scenario 4: experiment to study the heating ability of the developed system to the mattress. For all experiments, temperature of water at various locations were recorded to calculate the energy that the system could absorb and release using the peltier equations. The results showed that when supply electricity to peltier, hot water temperature rises and cold water temperature drops. The using of peltier TEC12712 resulted in a reduction in the time required to achieve the desired temperature for hot and cold water compare with TEC12706. Because of higher current and voltage were supplied to the TEC12712 peltier, resulted in increasing the released energy and absorbed energy of the peltier. In study the changing of stored energy in water and peltier energy revealed that the released energy and absorbed energy of peltier were agreed with the changing of store energy in water in both hot side and cold side. However, the changing of stored energy in water was less than the energy form peltier due to the efficiency of heat exchanging property of the device and the heat dissipation to the surrounding. For the study the effect of the heating and cooling ability of the system to the mattress showed that the developed system had high potential to be used for heating and cooling the mattress.

GROUND REACTION FORCE, FOOT PRESSURE, AND HAMSTRINGS TO QUADRICEPS RATIO IN RECREATIONAL RUNNERS WITH AND WITHOUT LOWER LIMB INJURY HISTORY

2023-11-03T13:03:46+07:00

This study was aim to examine the comparison and correlation of ground reaction force, foot pressure, and hamstrings to quadriceps ratio in recreational runners with and without lower limb injury history. Forty-nine recreational runners, who participated in the running assessment project at the physical therapy center, faculty of physical therapy, Mahidol university, were recruited in this study. According to the inclusion criteria, the data of 35 runners, who were 14 females and 21 males, were selected and divided into two groups: runners with (n = 19) and without (n = 16) lower limb injury history. All participants were tested the H/Q ratio using the isokinetic dynamometer at an angular velocity of 60, 120, and 180 degrees per second (º/s). The maximum ground reaction force and foot pressure were collected during walking with a gait analysis system (Zebris FDM-T). Comparison and correlation studies were analyzed with an independent t-test and Pearson’s correlation, respectively. A group of runners with lower limb injury history showed significantly higher maximum pressure at the midfoot and the heel than runners without lower limb injury history. Additionally, in runners without lower limb injury history, there was a significantly negative correlation between the H/Q ratio at all angular velocities and maximum force of a midfoot and a significantly positive correlation between the H/Q ratio at all angular velocities and maximum pressure at the forefoot. This study demonstrates that runners without lower limb injury history might have greater hamstrings and quadriceps femoris muscle balance, which could minimize the pressure at mid-foot and heel. Less impact on the ground could prevent the risk of lower limb injury. In order to provide management in runners with lower limb injuries, this study recommended that balancing between the Hamstring and Quadriceps muscles should be concerned in management of runners with lower limb injuries.

ASSESSMENT OF THE ROUTES POTENTIAL TO SUPPORT THE TRANSPORTATION OF FISHERY PRODUCTS FROM MYANMAR TO THE NORTHERN AND NORTHEASTERN REGIONS 1 OF THAILAND AND NEARBY AREAS OF LAO PEOPLE'S DEMOCRATIC REPUBLIC

2023-11-03T12:28:29+07:00

This research studied and assessed the potential of fisheries transportation routes from the Republic of the Union of Myanmar to the consumers in the northern and northeastern region 1, which consists of Udon Thani, Loei, Nong Bua Lam Phu, Nong Khai and Bueng Kan provinces of Thailand, Xayaboury, Luangprabang, Vientiane and Vientiane Capital of Laos PDR in 5 and 10 years framework. The result shows that the important sources of fishery products from the Republic of the Union of Myanmar are from Yangon and Myeik. The important and potential import channels are road transportation by truck from Yangon to Maesot checkpoint in Tak province and road transportation from Myeik to Singkhon checkpoint in Prachuap Khiri Khan Province. Both transportation channels will be able to reduce the transport distance by an average of 50.96 and 24.85 percent, respectively, and also reduce the transit time by an average of 77.61 and 53.04 percent, respectively, when compared with the main route from the ports of Yangon and Myeik to Ranong port. The suitable transportation mode for fishery products in Thailand in the next 5 years is road transport by using refrigerated trucks from Maesot and Singkhon checkpoint to the designed destinations in Thailand. For the study area in Laos PDR, the product could be transported by trucks and the Laos-China railway. In the next 10 years, although the construction of double-track railway has been completed on time and able to connect other countries in the region. However, with the limitations of rail transport with low mobility coupled with the characteristics of fishery products that the consumers want the products are fresh. Therefore, road transport is still suitable and could be the best to meet the needs of consumers.

ECO-EFFICIENCY OF THE CHEMICAL INDUSTRY: EVIDENCE FROM MAP TA PHUT IE, THAILAND

2023-11-03T12:48:37+07:00

An environmental efficiency analysis of chemical industrial enterprises in Thailand was studied by using measurement indicators that reflect the relationship of the economy and the environment. The economic and environmental indicators for 50 enterprises over a 3-year period was monitored which composed of electricity consumption, water consumption, level of wastewater discharge and the measurement of economic indicators. The economic indicators of the total income of each enterprise had a tendency to increase continuously. The third-year total expenses were higher than in the first and second years. With regard to the environmental indicators, which were water consumption and the wastewater discharge increased. These meant a water treatment plant should be applied. The discharged wastewater had the highest score. The second highest level was the water consumption and the third was energy consumption, respectively. It was found that the environmental efficiency of the water consumption level, wastewater discharge, and the energy consumption level had a tendency to increase. When analyzing this tendency in environmental economic efficiency by using a snapshot graph, it has shown every operational indicator in the 3-year period showed signs of sustainability. This is due to the amount of continuously increasing income. When considering key performance’s tendencies, all is found to be positioned in the Half Non-Eco-Efficiency in the second year. This changed to Full-Non-Eco-Efficiency in the third year. These showed that development is not based on sustainability. There are issues with the increased operational costs, the expensive resources and problems derived from the wastewater. The recommendation from these results is to provide reducing the high operational costs of chemical industrial enterprises as well.

FORECASTING ELECTRONIC MONEY SPENDING FOR NON-BANK

2023-11-03T12:51:24+07:00

This article aimed to develop a forecasting model for electronic money spending in non-bank. The monthly data was collected from the Bank of Thailand website from November 2015 to October 2021. The data were separated into 2 groups for training models (November 2015 – October 2020) and testing accuracy models (November 2020 – October 2021). The forecasting methods consist of Winter’s exponential smoothing method, the Box-Jenkins method and two combined forecasting methods consisting of the equal-weighted method and weight based on the ordinary least square coefficients method. The mean absolute percentage error (MAPE) and root mean square error (RMSE) were used to compare the accuracy of the models. The results show that the combined forecasting method using weight based on ordinary least square regression coefficients is the most appropriate model for forecasting electronic money for non-bank. This research is helpful to entrepreneurs and financial institutions in strategic plans and financial products designed to support the increase of electronic financial users.

EFFECT OF DYEING REPETITION ON COLOR CHANGE OF COTTON FABRIC WITH EXTRACTION OF DYES FROM INDIGO (INDIGOFERA TINCTORIA) LEAF POWDER

2023-11-03T12:55:16+07:00

The objective of this research was to study the effect of dyeing repetition on the color change of cotton fabric using indigo dye extracted from leaf of Indigofera tinctoria powder grown in Thailand. The fermentation method was used to extract the dyes, controlling variables in the experiment were the amount of indigo leaf powder, alkali and reducing agents content, dyeing temperature (at 25+5 degrees Celsius), dyeing time (was 5 mins) and they were repeated for staining. The research experiment analysed the data with the completed randomized design (CRD). The color values were measured in the CIE system for the mean color values and analysed of variance L*, a*, b*, C* and h*. The results showed that the dyed cotton samples could be dyed from Indigofera tinctoria leaf powder and the dye repetition had significant effect (p < 0.05) on the color value L*, b*, C* and h*. The L* value was decreased in luminance implying that color was darker, b* value was negative which meant an increase of blueness, the C* value increased in chromaticity, and the h* value increased and indicated that the color position was close to the blue color. Results also showed that the dyeing repetition effected the shade of the fabric sample. The repeating of dyeing process give darker shades on the cotton fabric sample several times. The result of the research showed that the indigo color extracted from Indigofera tinctoria leaf powder can be dyed on the cotton fabric.

PRODUCTION OF ALTERNATIVE AVIATION BIOFUELS FROM CATALYTIC PYROLYSIS OF WASTE VEGETABLE OIL IN A PILOT-SCALE CONTINUOUS SCREW PYROLYZER

2023-11-03T13:08:18+07:00

This research aims to produce aviation biofuel using waste from vegetable oil and animal fat by catalytic pyrolysis in a continuous pilot screw reactor. The raw materials used were waste from palm oil, used cooking oil and animal fat, which were generally composed of fatty acids and converted to products by calcined dolomite as the catalyst. The research work was divided into two parts. The 1^st part was the experiment in a bench reactor to determine the optimum conditions for use of waste palm oil and its reaction temperature and catalyst loading. The results of this part showed the optimum reaction temperature and catalyst loading as 425^๐C and 3 wt%, respectively. The product yields of liquid, solid and gas were 68.22, 3.43 and 28.50 wt%, respectively, whereas the composition in liquid was naphtha 14.70 wt%, kerosene 23.72 wt%, diesel 51.24 wt%, and residue 10.32 wt%. The 2^nd part was the production of liquid fuel from the raw material mentioned above in a pilot screw reactor with a waste palm oil feed rate of 800 kg/d. The optimum temperature, 425^๐C and 3 wt% catalyst loading from the 1^st part, were set up to operate the pilot reactor. The liquid, solid and gas yields of this operation using waste palm oil were 66.58, 8.08 and 25.34 wt%, respectively. The composition of the liquid product was consisted of naphtha 21.63 wt%, kerosene 23.57 wt%, diesel 48.22 wt%, and residue 5.58 wt%. The experimental results of 3 types of raw material in the pilot reactor gave a product yield range of 61-69 wt%. The composition in liquid biofuel was composed of naphtha, kerosene, diesel and fuel oil, in which kerosene proportion approximately of 21.95 to 23.90%. The estimated cost per kg of kerosene (aviation biofuel) for the production of 800 kg/d, including operating and investment costs, was 34.75 baht/kg, and the actual selling price of sustainable aviation fuel (SAF) from hydrocracking process is 133 baht/kg. The advantage of this process is lower cost production than the FT synthesis process and hydrocracking.

UTILIZATION OF FECES FROM NILE TILAPIA (OREOCHROMIS NILOTICUS) FOR CULTURE OF WATER FIRE AND SUBSTITUTE FOR USE CHLORELLA SP.

2023-11-03T13:10:45+07:00

This research aims to study the utilization of tilapia feces from cultured ponds as an alternative feed for increasing the aquaculture productivity of the water flea (Moina macrocopa). To investigate the productivity of the water flea cultivated with tilapia manure at 4 levels of 1, 3, 5 and 7 mL per 40 mL of water, water flea yields of 87±52, 90±55, 110±35 and 128±33 offspring were obtained, respectively, which were not significantly different (P > 0.05). Water flea feed was able to begin reproduction and yield the first generation asexually by 2 days. On average, 12 generations of water fleas were produced from the experiments that fed on tilapia manure and exhibited rapid growth. Therefore, the utilization of Nile tilapia feces can be an alternative feed for aquaculture of water fleas that can also rapidly increase productivity. This can solve the problem of the shortage of chlorella sp. as a feed for water fleas to reduce wastewater pollution in natural water sources and promote sustainable aquaculture.

editorial board

2024-01-22T13:07:54+07:00

Srinakharinwirot University (Journal of Science and Technology)