Journal of Science and Technology CRRU https://li01.tci-thaijo.org/index.php/jstcrru <p><em>Journal of Science and Technology CRRU</em></p> <p>ISSN 2821-9333 (Online)</p> <p><strong><em>Publication Frequency : </em></strong><em>2 issues per year (January-June), (July-December).</em></p> <p><strong><em>Aims and Scope:</em></strong><em> Pure and Applied Sciences, Mathematics and Applied Mathematics</em></p> คณะวิทยาศาสตร์และเทคโนโลยี มหาวิทยาลัยราชภัฏเชียงราย en-US Journal of Science and Technology CRRU <p><em>Journal of TCI is licensed under a Creative Commons </em><a href="https://creativecommons.org/licenses/by-nc-nd/4.0/"><em>Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)</em></a></p> The Solution of Diophantine Equation \frac{1^3}{u_1}+\frac{1^3}{u_2}+...+\frac{k^3}{u_k}=1 https://li01.tci-thaijo.org/index.php/jstcrru/article/view/262501 <p>In this paper, we describe solutions of the Diophantine equation on the following from: <img title="\frac{1^3}{u_1}+\frac{1^3}{u_2}+...+\frac{k^3}{u_k}=1" src="https://latex.codecogs.com/gif.latex?\frac{1^3}{u_1}+\frac{1^3}{u_2}+...+\frac{k^3}{u_k}=1" /> where <img title="2\leq u_1\leq u_2\leq ...\leq u_k" src="https://latex.codecogs.com/gif.latex?2\leq&amp;space;u_1\leq&amp;space;u_2\leq&amp;space;...\leq&amp;space;u_k" /> are integers. For our result, we obtain that the equation has one solution if <img title="u_1=2" src="https://latex.codecogs.com/gif.latex?u_1=2" /> three solution if <img title="u_1=3" src="https://latex.codecogs.com/gif.latex?u_1=3" /> and at least four general solutions if <img title="u_1=4" src="https://latex.codecogs.com/gif.latex?u_1=4" />. Moreover, there is a clear step-by-step method of proof following a mathematical process.</p> Laddawan Saethao Patchara Muangkarn Cholatis Suanoom Copyright (c) 2024 Chiang Rai Rajabhat University https://creativecommons.org/licenses/by-nc-nd/4.0 2024-06-25 2024-06-25 3 1 1 9 Effects of bio-extract from pineapple peel on the germination and growth of pea (Lathyrus oleraceus Lam.) https://li01.tci-thaijo.org/index.php/jstcrru/article/view/262168 <p>This research aims to study the effects of pineapple peel bio-extracts on the germination and growth of green peas. The bio-extract was diluted at ratios of 1:100, 1:200, 1:300, 1:400, and 1:500 (v/v) with water. Germination percentage was studied by soaking healthy pea seeds in bio-extract solutions of various dilutions compared to distilled water for 8 hours, then sowing them on germination dishes using the Top of paper method and watering with distilled water and bio-extract solutions at the previously mentioned dilution ratios for 48 hours. The appropriate concentration of bio-extract that resulted in the highest germination rate was found to be 1:200, with a percentage of 76.67 ± 5.03, whereas the control group had a germination rate of 58.33 ± 5.03. For the growth study of pea seedlings, the seeds were soaked in bio-extract for 2 hours, then planted on germination trays and watered with bio-extract solutions at different dilution levels compared to distilled water twice a day. The height and stem diameter of the seedlings were measured on days 2, 4, 6, 8, and 10, and the fresh weight was measured on day 10 of the experiment. It was found that the bio-extract solution at a dilution level of 1:200 resulted in pea seedlings with a height, stem diameter, and fresh weight on day 10 of 10.51 ± 0.87 centimeters, 2.20 ± 0.17 millimeters, and 1.97 ± 0.06 grams, respectively. This was compared to the control group with measurements of 7.39 ± 1.65 centimeters, 2.16 ± 0.40 millimeters, and 1.67 ± 0.40 grams, respectively.</p> Santichai Kaeonuan Wipawan Nunto Copyright (c) 2024 Chiang Rai Rajabhat University https://creativecommons.org/licenses/by-nc-nd/4.0 2024-06-25 2024-06-25 3 1 10 17 Process Development for Crispy Rice Cake from Glutinous Rice Flour https://li01.tci-thaijo.org/index.php/jstcrru/article/view/262179 <p>The purposes of this research were to study the process of producing crispy rice cakes using traditional methods, study the suitable conditions of producing for use with glutinous rice flour raw material and easily available equipment.</p> <p> The results of the study found that big wood mortar was important equipment for making crispy rice cake by traditional method. Hot steamed glutinous rice was pounded into dough, before being rolled into a round shape, drying rice dough sheet by sunlight and made crispy by grilling. The suitable conditions to produced rice dough sheets found that suitable temperature to replace using sunlight is 60<sup>º</sup>C for 1 hour while the appropriate thickness of rice dough sheets is 14 g/100 cm<sup>2</sup>. Development of crispy rice cake production process there are steps as follows: mixing all the ingredient together (glutinous rice flour, water, brown sugar and salt), steaming until the dough is cooked for 30 minutes, kneading cooked dough for 30 minutes, rolling the dough into sheets with a thickness 14 g/cm<sup>2</sup>, drying dough sheets in hot air oven at 60<sup>º</sup>C for 1 hour, cutting dough sheets into shapes and baking until crispy by convection oven at 200<sup>º</sup>C for 5 minutes.</p> <p> The sensory attribute acceptance of developed process recipe and traditional recipe were similar for the best taste and aroma. The products were accepted at level of high to very high preference. Texture and overall acceptance of the developed process were accepted at level of moderate to high preference. While the traditional recipe was accepted at level of high to very high preference for every characteristic. Moisture content and water activity of traditional recipe was higher than developed process recipe.</p> Watsana Kaewpho Copyright (c) 2024 Chiang Rai Rajabhat University https://creativecommons.org/licenses/by-nc-nd/4.0 2024-06-25 2024-06-25 3 1 18 27 An Investigation of the Effectiveness of Using Tracker Software to Enhance Academic Achievement in Simple Harmonic Motion among Grade 11 Students https://li01.tci-thaijo.org/index.php/jstcrru/article/view/262573 <p>This research aims to investigate the effectiveness of using tracker software to enhance the academic achievement of Grade 11 students in the topic of simple harmonic motion. A quasi-experimental research design was employed, utilizing a pre-test and post-test control group design. The sample was randomly divided into two groups: an experimental group (using tracker software) and a control group (using traditional lecture-based instruction). Both groups were subjected to a post-test to assess their academic achievement. Data were analyzed using a t-test to compare the statistically significant differences in academic achievement between the two groups. The results revealed that the percentage of mean scores between pre-test and post-test were 86.31 and 85.23, respectively. The post-test scores increased by 46.10%, with a mean pre-test score of 6.14 and a standard deviation of 4.01, while the mean post-test score was 11.39 and the standard deviation was 4.19. The t-test value was less than .05.</p> Artitaya Piamsup Rattanawadee Boonaoi Kanhathai Noicharoen Sarayut Pantian Copyright (c) 2024 Chiang Rai Rajabhat University https://creativecommons.org/licenses/by-nc-nd/4.0 2024-06-25 2024-06-25 3 1 28 34 Reckoning of time-velocity of change particle activated by time-dependent Cosine function external force in motion into uniform magnetic field https://li01.tci-thaijo.org/index.php/jstcrru/article/view/262058 <p>This research aimed to show the method of the time-dependent velocity of change particle +<em>q<sub>c</sub></em> in <em>y</em> axes and time-dependent velocity of change particle +<em>q<sub>c</sub> </em>in <em>z</em> axes. In which electrically charged particles are stimulated by external Cosine forces to move within an area with a magnetic field. Electrically charged particles are stimulated by external Cosine forces to move in the presence of a magnetic field. We can use technique method of variation of parameters and use technique integration by parts calculate the time-dependent velocity of charged particles. The magnetic field is constant at all times. The research results show that the time-dependent velocity of charged particles +<em>q<sub>c</sub></em> in <em>y </em>axes and <em>z </em>axes moving in a magnetic field has an oscillating motion similar to a wave group.</p> Artit Hutem Copyright (c) 2024 Chiang Rai Rajabhat University https://creativecommons.org/licenses/by-nc-nd/4.0 2024-06-25 2024-06-25 3 1 35 47 Angular Displacement Angular Velocity and Tension Force of Particle in the Pendulum Motion under drag Force and Time-Dependent External Force https://li01.tci-thaijo.org/index.php/jstcrru/article/view/262164 <p>This research aimed to study for time-dependent angular displacement angular velocity and tension force of particle mass <em>m<sub>k</sub></em> in the pendulum motion under air-resistance force and time-dependent external force 2 type. We can use the time-dependent external force 2 type in calculate the time-dependent angular displacement angular velocity and tension force of particle mass <em>m<sub>k</sub></em> in the pendulum motion. The time-dependent external force 2 type is <em>f<sub>0</sub></em>sin(<em>w<sub>fa</sub>t</em>) and <em>f<sub>0</sub></em>sin<sup>2</sup>(<em>w<sub>fa</sub>t</em>). This research, we can use Newton's law of motion to calculate the time-dependent angular displacement and the time-dependent angular velocity and the time-dependent tension force in polar coordinate. We can use the method of solving inhomogeneous second order differential equations by the parameter variation method. The work in this research compares the time-dependent angular displacement, the time-dependent angular velocity and the tension force that depends on two external forces. Research results: A pendulum motion subjected to an external force of type <em>f<sub>0</sub></em>sin<sup>2</sup>(<em>w<sub>fa</sub>t</em>) will cause the time-dependent angular displacement, the time-dependent angular velocity and the tension force in the string oscillates more up and down overall than a pendulum motion subjected to an external force, type <em>f<sub>0</sub></em>sin(<em>w<sub>fa</sub>t</em>).</p> Artit Hutem Copyright (c) 2024 Chiang Rai Rajabhat University https://creativecommons.org/licenses/by-nc-nd/4.0 2024-06-25 2024-06-25 3 1 48 65 Determining the amount of nutrients and pH of soil in maize growing areas using the X-ray fluorescence technique https://li01.tci-thaijo.org/index.php/jstcrru/article/view/262562 <p>This study determined the amount of nutrients and pH of soil in maize growing areas using the X-ray fluorescence technique. The results showed that the total elemental concentrations varied among the three fields, with nine elements detected: Si, Fe, Ca, Ti, Rh, Mn, Cl, K, and Zr. The macronutrients were present in very low concentrations. The soil pH values ranged from 7.02 to 7.34, indicating slightly acidic to moderately alkaline conditions, which is consistent with the characteristics of the Lopburi soil series. The potassium concentrations measured by the Kasetsart University soil test kit and XRF showed a similar trend. Areas with moderate potassium levels had a concentration less than 0.51%, while areas with high potassium levels had a concentration more than 0.76%. Silicon was the most abundant element in the soil.</p> Piyasuda Sudsa-ard Phonthip Buntham Thotsapon Buarod Sarayut Pantian Copyright (c) 2024 Chiang Rai Rajabhat University https://creativecommons.org/licenses/by-nc-nd/4.0 2024-06-25 2024-06-25 3 1 66 72 Pectin Extraction from Watermelon Rind for Application as a Coating on Apple Skin https://li01.tci-thaijo.org/index.php/jstcrru/article/view/262332 <p>The objective of this research was to study the extraction of pectin from Watermelon rind species Sonya Plus for application as a coating on Apple skin species Fuji. The extraction factors with citric acid concentrations of 0.025, 0.050, 0.075 and 0.100 molar at temperature of 90 °C for 60 minute and the chemical properties of pectin were analyzed and pectin was evaluated. Dipping with various chemicals to Maintain Quality of fresh apple pulp in the period at 0, 6 and 12 days at 8 °C. It was found that, the highest concentration of citric acid at which pectin can be extracted is 0.100 molar yielding 0.82 g of pectin and 8.17 %. The results of chemical properties showed that, the moisture content, the galacturonic acid ontent, the methoxyl content and the %DE content were 6.77, 1.76, 53.18, 8.21 and 54.42 respectively. Pectin coating 2 % and dipping with chemical in the period at 12 days at 8 °C. This resulted in the lowest weight loss at 4.15 % and the lowest firmness loss at 7.27 N/mm.</p> Ratri Bumee Patompong Thiangphet Kwandaw Jamjang Paklao Phoomyai Copyright (c) 2024 Chiang Rai Rajabhat University https://creativecommons.org/licenses/by-nc-nd/4.0 2024-06-25 2024-06-25 3 1 73 83 Effect of Marble Powder Mixed with Concrete on Mechanical Properties for Use as Concrete Roof Tiles https://li01.tci-thaijo.org/index.php/jstcrru/article/view/262026 <p>This research aims to study the physical properties of concrete roof tiles mixed with marble powder in various ratios, produced by molding the tiles with concrete containing a mixture of Portland cement type 1, sand, water, waterproofing solution and a substance that accelerates the formation of calcium chloride. with a percentage ratio of 21.73 : 59.78 : 16.30 : 1.53 : 0.66 and marble powder added in the ratio by mass of concrete and marble powder with a ratio by mass of 1:0, 0.9:0.1, 0.8:0.2, 0.7:0.3, 0.6:0.4 and 0.5:0.5 formed by mold size 33 x 42 x 1 centimeter. It was found that the appropriate amount of marble powder For mixing in concrete roof tiles, the ratio is 0.9:0.1. Tests have been carried out according to industrial standards, TIS 535-2013, and the test results following the requirements, with a transverse pressure value of 1,117.78 newtons, with a % of water absorption value was 9.68 each and the thermal conductivity is 0.02 W/m.K, under the standard for concrete roof tiles. The roof tiles from this research can be used as roofing material.</p> Nirat Saeyang Nongluk Chanpichai Copyright (c) 2024 Chiang Rai Rajabhat University https://creativecommons.org/licenses/by-nc-nd/4.0 2024-06-25 2024-06-25 3 1 84 94