Indonesian Journal of Engineering and Science <p><strong>Indonesian Journal of Engineering and Science (IJES) e-ISSN 2774-373X</strong> is a peer-reviewed journal that aims at the publication and dissemination of original research articles on the latest developments in all fields of engineering science and technology. The journal publishes original papers in English, which contribute to the understanding of engineering science and improvement of the engineering technology and education. Papers may be theoretical, experimental and paper review. The contribution should be unpublished before and not under consideration for publication elsewhere.</p> en-US (Gunawan) (Amir Arifin) Thu, 01 Dec 2022 10:28:28 +0000 OJS 60 DEVELOPMENT OF FINITE ELEMENT ANALYSIS PROGRAM FOR ROTORDYNAMIC PREDICTION OF SINGLE AND MULTI DISK ROTOR MODEL <p>The rotating equipment is a crucial part of system performance reliability. Vibration, as a characteristic of an oscillating body, is a fundamental parameter to determine the dynamic behaviour of the rotor system. The dynamic characteristics include natural frequency, critical speed, mode shape, and vibration response. This paper discussed the application of rotordynamics analysis as a tool to numerically predict the dynamic behaviour of a rotor system. The aim is to determine a rotor system's natural frequency and critical speed by a finite element analysis (FEA) program. The selected method is validated using various analytical methods from other references with small discrepancies in the result. The calculation of FEA using the computational program; they applied the developed program to describe the dynamic characteristic of single and multi-disk rotors. The developed works provided comprehensive results about a rotor system's natural frequency, mode shape, and critical speed and predicted the vibration response due to unbalance. However, other types of rotors, such as coaxial dual rotors, can be further investigated to make the program capable of the general purpose of the rotor. Validation with the real case problem could be an interesting investigation to satisfy the result of developed works.</p> Muhammad Idris, Zakie Anugia, Donny Mustika Copyright (c) 2022 Indonesian Journal of Engineering and Science Tue, 01 Nov 2022 00:00:00 +0000 EXPERIMENTAL IN HEAD TRACKING CONTROL OF A FOUR OMNI WHEELED MOBILE ROBOT SYSTEM <p>This article describes an experimental investigation into the head tracking and control of a four-wheeled Omni-Robot. This study described the control scheme of the omnidirectional mobile robot. Additionally, the kinematics of the mobile robot is presented., A mobile robot with four Omni wheels was also developed on real hardware to verify the controller architecture design. The robot system is modeled and then implemented with the Arduino Microcontroller. This robot has two rotary encoders for running on the x-axis and y-axis, respectively. The gyro sensor (MPU-6050) is placed in the robot's middle and tracks data obtained by yaw angle. MATLAB Simulink was used to find the PD controller based on manual adjustment. The control architecture was deployed to complete and run the experiment on the mobile robot to evaluate the outcomes. The experiment results show the robot's motion control improvement in various scenarios.</p> Srun Channareth, Lonh Vannsith, Ny Virbora Copyright (c) 2022 Indonesian Journal of Engineering and Science Tue, 01 Nov 2022 00:00:00 +0000 HIGH-EFFICIENCY PRODUCTION TECHNOLOGY OF PREFABRICATED PRESTRESSED COMPOSITE BEAMS <p>This paper proposes a construction technology for the precision control of the pedestal table and the overall tensioning method of the composite beam steel strand Given because of the critical technical issues, such as the deformation and cracking of the pedestal table during the prestressed composite beam production process, group tensioning, and control of steel bar slippage. Reinforcement fixing device research and development for node reinforcement arrangement and its technologies based on BIM simulation ensures efficient tensioning of prestressed superimposed beams and avoids reinforcement slippage.</p> Yin Baoquan , Lai PC, Yu Yabin Copyright (c) 2022 Indonesian Journal of Engineering and Science Tue, 01 Nov 2022 00:00:00 +0000 FAILURE ANALYSIS OF THE FLOUR PRESS MACHINE AND ALTERNATIVE SOLUTIONS AT PT ANEKA USAHA LABA JAYA UTAMA PESAWARAN <p>Processing chocolate from dried cocoa beans to become a ready-to-eat chocolate paste involves a long process, including separating the cocoa oil from the flour. The separation process is mechanized using a press machine with high pressure at a certain temperature level. However, a press machine deals with obstacles prone to failure and damage. This study aims to analyze the causes of the chocolate pressing machine's failure using hydraulic pressure and find alternative repair solutions. The cylinder of the machine press is made of stainless steel material and has a cylindrical geometry with a diameter of 23 mm and a tube length of 30 cm. Failure analysis is carried out by observing the machine's operating conditions, the procedure for its use, and the load imposed on the machine, including, in this case, the service life to date. Observations were also made on the form of failure, the type of damage, and each component's function. Thus, based on the data obtained and relates to the theoretical theory, the conditions that should occur are obtained. The study results showed that the damages occurred, such as press tube damage, deformed fins, clogged gaps between fins, worn support rods, corroded threads, worn and stiff seals, and bearing damage to rupture. More damage was caused by the tilted position of the machine so that it didn't move the flashlight anymore. The part of the machine must be repaired flat based on standard procedures operation and carry out periodic checks on machine components.</p> Gusri Akhyar Ibrahim, Arinal Hamni, Yanuar Burhanuddin, Achmad Yahya Teguh Panuju, Sahid Ar Rafi, Rizki Ramadhan Copyright (c) 2022 Indonesian Journal of Engineering and Science Tue, 01 Nov 2022 00:00:00 +0000 WEAR ANALYSIS OF VERTICAL COAL MILL PLATE <p>Vertical Coal Mill (VCM) is equipment for grinding and pulverizing coal into micron size. Rotary kilns then use the powders as fuel burners. The VCM has a housing section equipped with a lining plate as a wear and tear protector. The housing comprises segments with similar thicknesses and materials that are severe to wear due to gas-carrying solid particles hitting the surface. The specific material resilient to abrasion is required to extend operating services. This study aims to determine the wear properties of Hardlite and Everhard C500LE on the lining plate. Characterization of the samples, including composition, microstructure, hardness, and wear test. Microstructure observation shows that the more extensive and profound the wear marks formed, the higher the volume of exfoliated material. The test results show that the Fe-Cr-C hard-facing alloy significantly affects the hardness value of a material and its wear resistance. The hardness test results showed an average Hardlite overlay layer hardness value of 703 BHN (N/mm<sup>2</sup>), almost double that of Everhard C500LE.</p> Bertawan Bertawan, Diah Kusuma Pratiwi Copyright (c) 2022 Indonesian Journal of Engineering and Science Tue, 01 Nov 2022 00:00:00 +0000 PREDICTION OF AIR QUALITY INDEX USING DECISION TREE WITH DISCRETIZATION <p>Air quality is indicated by the Air Quality Index (AQI). Prediction or classification of AQI is an important research issue because it can impact many factors, such as the environment, health, transportation, agriculture, plantations, tourism, and education. The purpose of this study is to predict AQI using a decision tree. The results of calculating the performance of the decision tree method that implements the discretization technique show that this method is very good at predicting air quality, as indicated in particular by the Average Accuracy value of 99.05%, Macro Precision of 78.59%, and Macro Recall of 77.46%.</p> Ning Eliyati, Mauizzatil Rahmayani, Shohif Wijaya, Des Alwine Zayanti, Endang Sri Kresnawati, Yulia Resti Copyright (c) 2022 Indonesian Journal of Engineering and Science Tue, 01 Nov 2022 00:00:00 +0000 CLASSIFICATION OF DISEASES AND PESTS OF MAIZE USING MULTINOMIAL LOGISTIC REGRESSION BASED ON RESAMPLING TECHNIQUE OF K-FOLD CROSS-VALIDATION <p>Some of the obstacles in the cultivation of maize that cause low productivity of maize yields are diseases and pests. Early detection of maize diseases and pests is expected to reduce farmer losses. A system for the early detection of diseases and pests can be created by classifying them based on digital images. This study aimed to classify maize diseases and pests using multinomial logistic regression. The model and testing resampling were based on resampling technique of k-fold cross-validation. The research data was obtained from the RGB color feature extraction process for each object in each class of diseases and pests of corn. The results showed that the classification into seven classes using five folds had an accuracy rate of 99.85%, macro precision of 98.59%, and macro recall of 98.15%.</p> Yulia Resti, Desi Herlina Saraswati, Des Alwine Zayanti, Ning Eliyati Copyright (c) 2022 Indonesian Journal of Engineering and Science Tue, 01 Nov 2022 00:00:00 +0000